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Publication
Journal: American Journal of Pathology
May/18/2009
Abstract
Here we used the Met-1 cell line in an orthotopic transplantation model in FVB/N mice to dissect the role of the Cav-1(P132L) mutation in human breast cancer. Identical experiments were performed in parallel with wild-type Cav-1. Cav-1(P132L) up-regulated the expression of estrogen receptor-alpha as predicted, because only estrogen receptor-alpha-positive patients have been shown to harbor Cav-1(P132L) mutations. In the context of primary tumor formation, Cav-1(P132L) behaved as a loss-of-function mutation, lacking any tumor suppressor activity. In contrast, Cav-1(P132L) caused significant increases in cell migration, invasion, and experimental metastasis, consistent with a gain-of-function mutation. To identify possible molecular mechanism(s) underlying this invasive gain-of-function activity, we performed unbiased gene expression profiling. From this analysis, we show that the Cav-1(P132L) expression signature contains numerous genes that have been previously associated with cell migration, invasion, and metastasis. These include i) secreted growth factors and extracellular matrix proteins (Cyr61, Plf, Pthlh, Serpinb5, Tnc, and Wnt10a), ii) proteases that generate EGF and HGF (Adamts1 and St14), and iii) tyrosine kinase substrates and integrin signaling/adapter proteins (Akap13, Cdcp1, Ddef1, Eps15, Foxf1a, Gab2, Hs2st1, and Itgb4). Several of the P132L-specific genes are also highly expressed in stem/progenitor cells or are associated with myoepithelial cells, suggestive of an epithelial-mesenchymal transition. These results directly support clinical data showing that patients harboring Cav-1 mutations are more likely to undergo recurrence and metastasis.
Publication
Journal: Journal of Clinical Investigation
October/5/2014
Abstract
Ewing's sarcoma is a highly malignant bone tumor found in children and adolescents, and the origin of this malignancy is not well understood. Here, we introduced a Ewing's sarcoma-associated genetic fusion of the genes encoding the RNA-binding protein EWS and the transcription factor ETS (EWS-ETS) into a fraction of cells enriched for osteochondrogenic progenitors derived from the embryonic superficial zone (eSZ) of long bones collected from late gestational murine embryos. EWS-ETS fusions efficiently induced Ewing's sarcoma-like small round cell sarcoma formation by these cells. Analysis of the eSZ revealed a fraction of a precursor cells that express growth/differentiation factor 5 (Gdf5), the transcription factor Erg, and parathyroid hormone-like hormone (Pthlh), and selection of the Pthlh-positive fraction alone further enhanced EWS-ETS-dependent tumor induction. Genes downstream of the EWS-ETS fusion protein were quite transcriptionally active in eSZ cells, especially in regions in which the chromatin structure of the ETS-responsive locus was open. Inhibition of β-catenin, poly (ADP-ribose) polymerase 1 (PARP1), or enhancer of zeste homolog 2 (EZH2) suppressed cell growth in a murine model of Ewing's sarcoma, suggesting the utility of the current system as a preclinical model. These results indicate that eSZ cells are highly enriched in precursors to Ewing's sarcoma and provide clues to the histogenesis of Ewing's sarcoma in bone.
Publication
Journal: BMC Medical Genetics
January/2/2013
Abstract
BACKGROUND
While some factors of breast morphology, such as density, are directly implicated in breast cancer, the relationship between breast size and cancer is less clear. Breast size is moderately heritable, yet the genetic variants leading to differences in breast size have not been identified.
METHODS
To investigate the genetic factors underlying breast size, we conducted a genome-wide association study (GWAS) of self-reported bra cup size, controlling for age, genetic ancestry, breast surgeries, pregnancy history and bra band size, in a cohort of 16,175 women of European ancestry.
RESULTS
We identified seven single-nucleotide polymorphisms (SNPs) significantly associated with breast size (p<5.10(-8)): rs7816345 near ZNF703, rs4849887 and (independently) rs17625845 flanking INHBB, rs12173570 near ESR1, rs7089814 in ZNF365, rs12371778 near PTHLH, and rs62314947 near AREG. Two of these seven SNPs are in linkage disequilibrium (LD) with SNPs associated with breast cancer (those near ESR1 and PTHLH), and a third (ZNF365) is near, but not in LD with, a breast cancer SNP. The other three loci (ZNF703, INHBB, and AREG) have strong links to breast cancer, estrogen regulation, and breast development.
CONCLUSIONS
These results provide insight into the genetic factors underlying normal breast development and show that some of these factors are shared with breast cancer. While these results do not directly support any possible epidemiological relationships between breast size and cancer, this study may contribute to a better understanding of the subtle interactions between breast morphology and breast cancer risk.
Publication
Journal: American Journal of Pathology
March/10/2011
Abstract
Multiple osteochondromas (MO) is an autosomal dominant disorder caused by germline mutations in EXT1 and/or EXT2. In contrast, solitary osteochondroma (SO) is nonhereditary. Products of the EXT gene are involved in heparan sulfate (HS) biosynthesis. In this study, we investigated whether osteochondromas arise via either loss of heterozygosity (2 hits) or haploinsufficiency. An in vitro three-dimensional chondrogenic pellet model was used to compare heterozygous bone marrow-derived mesenchymal stem cells (MSCs EXT(wt/-)) of MO patients with normal MSCs and the corresponding tumor specimens (presumed EXT(-/-)). We demonstrated a second hit in EXT in five of eight osteochondromas. HS chain length and structure, in vitro chondrogenesis, and EXT expression levels were identical in both EXT(wt/-) and normal MSCs. Immunohistochemistry for HS, HS proteoglycans, and HS-dependent signaling pathways (eg, TGF-β/BMP, Wnt, and PTHLH) also showed no differences. The cartilaginous cap of osteochondroma contained a mixture of HS-positive and HS-negative cells. Because a heterozygous EXT mutation does not affect chondrogenesis, EXT, HS, or downstream signaling pathways in MSCs, our results refute the haploinsufficiency theory. We found a second hit in 63% of analyzed osteochondromas, supporting the hypothesis that osteochondromas arise via loss of heterozygosity. The detection of the second hit may depend on the ratio of HS-positive (normal) versus HS-negative (mutated) cells in the cartilaginous cap of the osteochondroma.
Publication
Journal: Osteoarthritis and Cartilage
April/2/2012
Abstract
OBJECTIVE
To identify the molecular differences between the transient and permanent chondrocyte phenotype in osteophytic and articular cartilage.
METHODS
Total RNA was isolated from the cartilaginous layer of osteophytes and from intact articular cartilage from knee joints of 15 adult human donors and subjected to cDNA microarray analysis. The differential expression of relevant genes between these two cartilaginous tissues was additionally validated by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and by immunohistochemistry.
RESULTS
Among 47,000 screened transcripts, 600 transcripts were differentially expressed between osteophytic and articular chondrocytes. Osteophytic chondrocytes were characterized by increased expression of genes involved in the endochondral ossification process [bone gamma-carboxyglutamate protein/osteocalcin (BGLAP), bone morphogenetic protein-8B (BMP8B), collagen type I, alpha 2 (COL1A2), sclerostin (SOST), growth arrest and DNA damage-induced gene 45ß (GADD45ß), runt-related transcription factor 2 (RUNX2)], and genes encoding tissue remodeling enzymes [matrix metallopeptidase (MMP)9, 13, hyaluronan synthase 1 (HAS1)]. Articular chondrocytes expressed increased transcript levels of antagonists and inhibitors of the BMP- and Wnt-signaling pathways [Gremlin-1 (GREM1), frizzled-related protein (FRZB), WNT1 inducible signaling pathway protein-3 (WISP3)], as well as factors that inhibit terminal chondrocyte differentiation and endochondral bone formation [parathyroid hormone-like hormone (PTHLH), sex-determining region Y-box 9 (SOX9), stanniocalcin-2 (STC2), S100 calcium binding protein A1 (S100A1), S100 calcium binding protein B (S100B)]. Immunohistochemistry of tissue sections for GREM1 and BGLAP, the two most prominent differentially expressed genes, confirmed selective detection of GREM1 in articular chondrocytes and that of BGLAP in osteophytic chondrocytes and bone.
CONCLUSIONS
Osteophytic and articular chondrocytes significantly differ in their gene expression pattern. In articular cartilage, a prominent expression of antagonists inhibiting the BMP- and Wnt-pathway may serve to lock and stabilize the permanent chondrocyte phenotype and thus prevent their terminal differentiation. In contrast, osteophytic chondrocytes express genes with roles in the endochondral ossification process, which may account for their transient phenotype.
Publication
Journal: Journal of Endocrinology
March/14/2010
Abstract
The calcium-sensing receptor (CaR or CASR as listed in the MGI Database) is a G protein-coupled receptor that binds and signals in response to extracellular calcium and other polycations. It is highly expressed on parathyroid and kidney cells, where it participates in the regulation of systemic calcium homeostasis. It is also expressed on many other cell types and is involved in a wide array of biological functions such as cell growth and differentiation, ion transport, and hormone secretion. It has been described to couple to several different G proteins including Galpha(i/0), Galpha(q/11), and Galpha(12/13). Recently, it has also been shown to stimulate cAMP production by coupling to Galpha(s) in immortalized or malignant breast cells. The CaR is expressed on cells in the anterior pituitary and had previously been described to stimulate cAMP production in these cells. In this report, we examined signaling from the CaR in murine pituitary corticotroph-derived, AtT-20 cells. We found that CaR activation led to the stimulation of cAMP production, and PTH-related protein (PTHrP or PTHLH as listed in the MGI Database) and ACTH secretion from these cells. Furthermore, manipulation of cAMP levels was able to modulate PTHrP and ACTH secretion independent of changes in extracellular calcium. Finally, we demonstrated that the CaR couples to Galpha(s) in AtT-20 cells. Therefore, in pituitary corticotroph-like cells, as in breast cancer cells, the CaR utilizes Galpha(s) and activates cAMP production to stimulate hormone secretion.
Publication
Journal: Journal of Clinical Investigation
June/27/2005
Abstract
Short digits (Dsh) is a radiation-induced mouse mutant. Homozygous mice are characterized by multiple defects strongly resembling those resulting from Sonic hedgehog (Shh) inactivation. Heterozygous mice show a limb reduction phenotype with fusion and shortening of the proximal and middle phalanges in all digits, similar to human brachydactyly type A1, a condition caused by mutations in Indian hedgehog (IHH). We mapped Dsh to chromosome 5 in a region containing Shh and were able to demonstrate an inversion comprising 11.7 Mb. The distal breakpoint is 13.298 kb upstream of Shh, separating the coding sequence from several putative regulatory elements identified by interspecies comparison. The inversion results in almost complete downregulation of Shh expression during E9.5-E12.5, explaining the homozygous phenotype. At E13.5 and E14.5, however, Shh is upregulated in the phalangeal anlagen of Dsh/+ mice, at a time point and in a region where WT Shh is never expressed. The dysregulation of Shh expression causes the local upregulation of hedgehog target genes such as Gli1-3, patched, and Pthlh, as well as the downregulation of Ihh and Gdf5. This results in shortening of the digits through an arrest of chondrocyte differentiation and the disruption of joint development.
Publication
Journal: Human Molecular Genetics
July/7/2009
Abstract
Because both ovarian and breast cancer are hormone-related and are known to have some predisposition genes in common, we evaluated 11 of the most significant hits (six with confirmed associations with breast cancer) from the breast cancer genome-wide association study for association with invasive ovarian cancer. Eleven SNPs were initially genotyped in 2927 invasive ovarian cancer cases and 4143 controls from six ovarian cancer case-control studies. Genotype frequencies in cases and controls were compared using a likelihood ratio test in a logistic regression model stratified by study. Initially, three SNPs (rs2107425 in MRPL23, rs7313833 in PTHLH, rs3803662 in TNRC9) were weakly associated with ovarian cancer risk and one SNP (rs4954956 in NXPH2) was associated with serous ovarian cancer in non-Hispanic white subjects (P-trend < 0.1). These four SNPs were then genotyped in an additional 4060 cases and 6308 controls from eight independent studies. Only rs4954956 was significantly associated with ovarian cancer risk both in the replication study and in combined analyses. This association was stronger for the serous histological subtype [per minor allele odds ratio (OR) 1.07 95% CI 1.01-1.13, P-trend = 0.02 for all types of ovarian cancer and OR 1.14 95% CI 1.07-1.22, P-trend = 0.00017 for serous ovarian cancer]. In conclusion, we found that rs4954956 was associated with increased ovarian cancer risk, particularly for serous ovarian cancer. However, none of the six confirmed breast cancer susceptibility variants we tested was associated with ovarian cancer risk. Further work will be needed to identify the causal variant associated with rs4954956 or elucidate its function.
Publication
Journal: Osteoarthritis and Cartilage
September/4/2013
Abstract
OBJECTIVE
Increasing evidence points to a strong genetic component to osteoarthritis (OA) and that certain changes that occur in osteoarthritic cartilage recapitulate the developmental process of endochondral ossification. As zebrafish are a well validated model for genetic studies and developmental biology, our objective was to establish the spatiotemporal expression pattern of a number of OA susceptibility genes in the larval zebrafish providing a platform for functional studies into the role of these genes in OA.
METHODS
We identified the zebrafish homologues for Mcf2l, Gdf5, PthrP/Pthlh, Col9a2, and Col10a1 from the Ensembl genome browser. Labelled probes were generated for these genes and in situ hybridisations were performed on wild type zebrafish larvae. In addition, we generated transgenic reporter lines by modification of bacterial artificial chromosomes (BACs) containing full length promoters for col2a1 and col10a1.
RESULTS
For the first time, we show the spatiotemporal expression pattern of Mcf2l. Furthermore, we show that all six putative OA genes are dynamically expressed during zebrafish larval development, and that all are expressed in the developing skeletal system. Furthermore, we demonstrate that the transgenic reporters we have generated for col2a1 and col10a1 can be used to visualise chondrocyte hypertrophy in vivo.
CONCLUSIONS
In this study we describe the expression pattern of six OA susceptibility genes in zebrafish larvae and the generation of two new transgenic lines marking chondrocytes at different stages of maturation. Moreover, the tools used demonstrate the utility of the zebrafish model for functional studies on genes identified as playing a role in OA.
Publication
Journal: Journal of Pathology
November/5/2006
Abstract
Hedgehog (HH) signalling is important for specific developmental processes, and aberrant, increased activity has been described in various tumours. Disturbed HH signalling has also been implicated in the hereditary syndrome, Multiple Osteochondromas. Indian Hedgehog (IHH), together with parathyroid hormone-like hormone (PTHLH), participates in the organization of growth plates in long bones. PTHLH signalling is absent in osteochondromas, benign tumours arising adjacent to the growth plate, but is reactivated when these tumours undergo malignant transformation towards secondary peripheral chondrosarcoma. We describe a gradual decrease in the expression of Patched (PTCH) and glioma-associated oncogene homologue 1 (GLI1) (both transcribed upon IHH activity), and GLI2 with increasing malignancy, suggesting that IHH signalling is inactive and PTHLH signalling is IHH independent in secondary peripheral chondrosarcomas. cDNA expression profiling and immunohistochemical studies suggest that transforming growth factor-beta (TGF-beta)-mediated proliferative signalling is active in high-grade chondrosarcomas since TGF-beta downstream targets were upregulated in these tumours. This is accompanied by downregulation of energy metabolism-related genes and upregulation of the proto-oncogene jun B. Thus, the tight regulation of growth plate organization by IHH signalling is still seen in osteochondroma, but gradually lost during malignant transformation to secondary peripheral chondrosarcoma and subsequent progression. TGF-beta signalling is stimulated during secondary peripheral chondrosarcoma progression and could potentially regulate the retained activity of PTHLH.
Publication
Journal: Cancer Science
May/30/2007
Abstract
An accurate assessment of the cervical lymph node metastasis status in oral cavity cancer not only helps predict the prognosis of patients, but also helps surgeons to perform the appropriate treatment. We investigated the utilization of microarray technology focusing on the differences in gene expression profiles between primary tumors of oral squamous cell carcinoma that had metastasized to cervical lymph nodes and those that had not metastasized in the hope of finding new biomarkers to serve for diagnosis and treatment of oral cavity cancer. To design this experiment, we prepared two groups: the learning case group with 30 patients and the test case group with 13 patients. All tissue samples were performed using laser captured microdissection to yield cancer cells, and RNA was isolated from purified cancer cells. To identify a predictive gene expression signature, the different gene expressions between the two groups with and without metastasis in the learning case (n = 30) were analyzed, and the 85 genes expressed differentially were selected. Subsequently, to construct a more accurate prediction model, we further selected the genes with a high power for prediction from the 85 genes using the AdaBoost algorithm. The eight candidate genes, DCTD, IL-15, THBD, GSDML, SH3GL3, PTHLH, RP5-1022P6 and C9orf46, were selected to achieve the minimum error rate. Quantitative reverse transcription-polymerase chain reaction was carried out to validate the selected genes. From these statistical methods, the prediction model was constructed including the eight genes and this model was evaluated by using the test case group. The results in 12 of 13 cases ( approximately 92.3%) were predicted correctly.
Publication
Journal: Circulation. Cardiovascular genetics
February/16/2012
Abstract
BACKGROUND
Peripartum (PP) cardiomyopathy (CM) is a rare condition of unknown etiology that occurs in late pregnancy or early postpartum. Initial evidence suggests that genetic factors may influence PPCM. This study evaluated and replicated genome-wide association of single nucleotide polymorphisms with PPCM.
RESULTS
Genome-wide single nucleotide polymorphisms in women with verified PPCM diagnosis (n=41) were compared separately with local control subjects (n=49 postmenopausal age-discordant women with parity ≥1 and no heart failure) and iControls (n=654 women ages 30 to 84 years with unknown phenotypes). A replication study of independent population samples used new cases (PPCM2, n=30) compared with new age-discordant control subjects (local2, n=124) and with younger control subjects (n=89) and obstetric control subjects (n=90). A third case set of pregnancy-associated CM cases not meeting strict PPCM definitions (n=29) was also studied. In the genome-wide association study, 1 single nucleotide polymorphism (rs258415) met genome-wide significance for PPCM versus local control subjects (P=2.06×10(-8); odds ratio [OR], 5.96). This was verified versus iControls (P=7.92×10(-19); OR, 8.52). In the replication study for PPCM2 cases, rs258415 (ORs are per C allele) replicated at P=0.009 versus local2 control subjects (OR, 2.26). This replication was verified for PPCM2 versus younger control subjects (P=0.029; OR, 2.15) and versus obstetric control subjects (P=0.013; OR, 2.44). In pregnancy-associated cardiomyopathy cases, rs258415 had a similar effect versus local2 control subjects (P=0.06; OR, 1.79), younger control subjects (P=0.14; OR, 1.65), and obstetric control subjects (P=0.038; OR, 1.99).
CONCLUSIONS
Genome-wide association with PPCM was discovered and replicated for rs258415 at chromosome 12p11.22 near PTHLH. This study indicates a role of genetic factors in PPCM and provides a new locus for further pathophysiological and clinical investigation.
Publication
Journal: Journal of Clinical Investigation
June/1/2014
Abstract
Bone metastasis is a frequent complication of breast cancer that is often accelerated by TGF-β signaling; however, little is known about how the TGF-β pathway is regulated during bone metastasis. Here we report that deleted in liver cancer 1 (DLC1) is an important regulator of TGF-β responses and osteolytic metastasis of breast cancer cells. In murine models, breast cancer cells lacking DLC1 expression exhibited enhanced capabilities of bone metastasis. Knockdown of DLC1 in cancer cells promoted bone metastasis, leading to manifested osteolysis and accelerated death in mice, while DLC1 overexpression suppressed bone metastasis. Activation of Rho-ROCK signaling in the absence of DLC1 mediated SMAD3 linker region phosphorylation and TGF-β-induced expression of parathyroid hormone-like hormone (PTHLH), leading to osteoclast maturation for osteolytic colonization. Furthermore, pharmacological inhibition of Rho-ROCK effectively reduced PTHLH production and breast cancer bone metastasis in vitro and in vivo. Evaluation of clinical breast tumor samples revealed that reduced DLC1 expression was linked to elevated PTHLH expression and organ-specific metastasis to bone. Overall, our findings define a stroma-dependent paradigm of Rho signaling in cancer and implicate Rho-TGF-β crosstalk in osteolytic bone metastasis.
Publication
Journal: Breast Cancer Research
June/24/2012
Abstract
BACKGROUND
Genome-wide association studies, focusing primarily on unilateral breast cancer, have identified single nucleotide polymorphisms (SNPs) in a number of genomic regions that have alleles associated with a significantly increased risk of breast cancer. In the current study we evaluate the contributions of these previously identified regions to the risk of developing contralateral breast cancer. The most strongly disease-associated SNPs from prior studies were tested for association with contralateral breast cancer. A subset of these SNPs, selected upon their main effects on contralateral breast cancer risk was further evaluated for interaction with treatment modalities and estrogen receptor (ER) status.
METHODS
We genotyped 21 SNPs in 708 women with contralateral breast cancer and 1394 women with unilateral breast cancer who serve as the cases and controls in the Women's Environment, Cancer and Radiation Epidemiology (WECARE) Study. Records of treatment and ER status were available for most of WECARE Study participants. Associations of SNP genotypes and risk for contralateral breast cancer were calculated with multivariable adjusted conditional logistic regression methods.
RESULTS
Multiple SNPs in the FGFR2 locus were significantly associated with contralateral breast cancer, including rs1219648 (per allele rate ratio (RR) = 1.25, 95%CI = 1.08-1.45). Statistically significant associations with contralateral breast cancer were also observed at rs7313833, near the PTHLH gene (per allele RR = 1.26, 95%CI = 1.08-1.47), rs13387042 (2q35) (per allele RR = 1.19, 95%CI = 1.02-1.37), rs13281615 (8q24) (per allele RR = 1.21, 95%CI = 1.04-1.40), and rs11235127 near TMEM135 (per allele RR = 1.26, 95%CI = 1.04-1.53). The A allele of rs13387042 (2q35) was significantly associated with contralateral breast cancer in ER negative first tumors while the A allele of rs11235127 (near TMEM135) was significantly associated with contralateral breast cancer in ER positive first tumors. Although some SNP genotypes appeared to modify contralateral breast cancer risk with respect to tamoxifen treatment or particular radiation doses, trend tests for such effects were not significant.
CONCLUSIONS
Our results indicate that some common risk variants associated with primary breast cancer also increase risk for contralateral breast cancer, and that these risks vary with the ER status of the first tumor.
Publication
Journal: Laryngoscope
May/4/2005
Abstract
OBJECTIVE
To examine gene expression profiles in squamous cell carcinoma of the oral cavity (oral SCC) compared with histologically matched normal tissue.
METHODS
Fresh-frozen tissue was prospectively obtained from individuals undergoing surgical resections for oral SCC.
METHODS
RNA was extracted from seven sets of oral SCC and matched normal tissue. Gene expression profiles were obtained by interrogation of Affymetrix Gene Chip Arrays with cRNA prepared from the tissue. Expression values were subjected to a paired t test. Genes that were judged to differ between oral SCC and normal tissue were annotated according to their name in the Affymetrix Netaffx database and according to their function as indicated by their Gene Ontology Consortium number.
RESULTS
Of the 10,599 probe sets that were analyzed, 523 genes were abnormally expressed in SCC of the head and neck (P < or = .01), and 417 of these genes were abnormally expressed in all seven tumors in the same manner. Hierarchical clustering of the 121 genes that were abnormally expressed in cancerous relative to normal tissue (P < or = .001) showed that the tissue segregated into two groups consisting of normal and transformed tissue, as expected. The abnormal expression of two genes that were up regulated in oral SCC (ADAM 12 and PTHLH) and two genes that were down-regulated in SCCHN (EMP-1 and P11) were confirmed by real-time polymerase chain reaction and immunohistochemistry (ADAM 12) using additional sets of tissue.
CONCLUSIONS
The data showed that oral SCC aberrantly express genes in cellular pathways related to proliferation, apoptosis, extracellular matrix degradation, adhesion, transforming growth factor-beta signaling, and transcription. Further work is needed to determine the role of these genes in the development and progression of oral SCC.
Publication
Journal: Oral Oncology
June/25/2012
Abstract
The development of locoregional recurrence is the main reason for treatment failure in head and neck squamous cell carcinomas (HNSCC) and the remaining of tumor cells in surgical margins is associated with recurrence. Surgical margins are considered negative based on histologic assessment of the pathological specimen. However, this method lacks sensitivity in identifying cells that already started malignant transformation but have not yet developed a pathologic phenotype. We investigated the usefulness of assessing the expression of PTHLH, EPCAM, MMP9, LGALS1 and MET for the detection of molecular alterations in histologically negative surgical margins and determine the correlation of these tumor-related alterations with clinical and prognostic parameters. Differential gene expression was determined by quantitative RT-PCR analyses in normal mucosa, HNSCC and negative margin samples. Thirty-eight percent of the histologically negative surgical margins examined were margin-positive for overexpression of at least one of the genes evaluated. Moreover, MMP9 and PTHLH overexpression in the surgical margins was associated with the development of second primary tumors (p=0.002) and lower rates of local control (log rank test p=0.022; HR=4.186; p=0.035), respectively. These findings demonstrate that the overexpression of tumor-related genes in histologically negative surgical margins is a frequent event. The use of qRT-PCR may be an useful tool in detecting actually negative HNSCC surgical margins and the overexpression of specific genes in these margins could be helpful in the identification of patients with a higher risk of developing second primary tumors and local recurrences, thus aiding the surgeon in the delineation of the HNSCC resection extent and helping in the planning of adjuvant therapy.
Publication
Journal: Human Molecular Genetics
June/28/2010
Abstract
Parathyroid hormone-like hormone (PTHLH) is an important chondrogenic regulator; however, the gene has not been directly linked to human disease. We studied a family with autosomal-dominant Brachydactyly Type E (BDE) and identified a t(8;12)(q13;p11.2) translocation with breakpoints (BPs) upstream of PTHLH on chromosome 12p11.2 and a disrupted KCNB2 on 8q13. We sequenced the BPs and identified a highly conserved Activator protein 1 (AP-1) motif on 12p11.2, together with a C-ets-1 motif translocated from 8q13. AP-1 and C-ets-1 bound in vitro and in vivo at the derivative chromosome 8 breakpoint [der(8) BP], but were differently enriched between the wild-type and BP allele. We differentiated fibroblasts from BDE patients into chondrogenic cells and found that PTHLH and its targets, ADAMTS-7 and ADAMTS-12 were downregulated along with impaired chondrogenic differentiation. We next used human and murine chondrocytes and observed that the AP-1 motif stimulated, whereas der(8) BP or C-ets-1 decreased, PTHLH promoter activity. These results are the first to identify a cis-directed PTHLH downregulation as primary cause of human chondrodysplasia.
Publication
Journal: Physiological Genomics
March/19/2009
Abstract
Early embryonic development in the pig is characterized by a rapid elongation of the conceptus trophectoderm on days 11-12 of gestation. Initially, the conceptus trophoblast is morphologically rearranged from a 10-mm sphere into a tubular shape, transitioning into a thin filamentous form >150 mm in length in 2-3 h, followed by continued expansion within the uterine lumen for several days. Conceptus elongation is critical for establishing adequate placental surface area needed for embryo and fetal survival throughout gestation. The objective of this study was to characterize conceptus gene expression during trophoblastic elongation and the early attachment to the uterine endometrium on days 11-14 of gestation with the GeneChip Porcine Genome Array. In all, 3,759 different probe sets were statistically different in at least one comparison [spherical vs. tubular, spherical vs. day 12 filamentous (D12F), spherical vs. day 14 filamentous (D14F), tubular vs. D12F, tubular vs. D14F, and D12F vs. D14F]. When restricted to the spherical vs. D12F and D12F vs. D14F comparisons, 482 and 232 genes, respectively, were statistically different with greater than twofold change in expression. Utilization of k-means clustering, in addition to the Database for Annotation, Visualization, and Integrated Discovery (DAVID), identified genes of interest. Quantitative RT-PCR expression profiles for interferon-gamma (IFNG), heat shock protein 27 kDa (HSPB1), angiomotin, B-cell linker (BLNK), chemokine ligand 14 (CXCL14), parathyroid hormone-like hormone (PTHLH), and maspin were supportive of the GeneChip Porcine Genome Array data.
Publication
Journal: Journal of Dental Research
March/29/2015
Abstract
The aim of the study was to characterize the molecular relationship between ameloblastoma and keratocystic odontogenic tumor (KCOT) by means of a genome-wide expression analysis. Total RNA from 27 fresh tumor samples of 15 solid/multicystic intraosseous ameloblastomas and 12 sporadic KCOTs was hybridized on Affymetrix whole genome arrays. Hierarchical clustering separated ameloblastomas and KCOTs into 2 distinct groups. The gene set enrichment analysis based on 303 dental genes showed a similar separation of ameloblastomas and KCOTs. Early dental epithelial markers PITX2, MSX2, DLX2, RUNX1, and ISL1 were differentially overexpressed in ameloblastoma, indicating its dental identity. Also, PTHLH, a hormone involved in tooth eruption and invasive growth, was one of the most differentially upregulated genes in ameloblastoma. The most differentially overexpressed genes in KCOT were squamous epithelial differentiation markers SPRR1A, KRTDAP, and KRT4, as well as DSG1, a component of desmosomal cell-cell junctions. Additonally, the epithelial stem cell marker SOX2 was significantly upregulated in KCOT when compared with ameloblastoma. Taken together, the gene expression profile of ameloblastoma reflects differentiation from dental lamina toward the cap/bell stage of tooth development, as indicated by dental epithelium-specific transcription factors. In contrast, gene expression of KCOT indicates differentiation toward keratinocytes.
Publication
Journal: BMC Cancer
March/20/2014
Abstract
BACKGROUND
The WW domain containing protein WWOX has been postulated to behave as a tumor suppressor in breast and other cancers. Expression of this protein is lost in over 70% of ER negative tumors. This prompted us to investigate the phenotypic and gene expression effects of loss of WWOX expression in breast cells.
METHODS
Gene expression microarrays and standard in vitro assays were performed on stably silenced WWOX (shRNA) normal breast cells. Bioinformatic analyses were used to identify gene networks and transcriptional regulators affected by WWOX silencing. Co-immunoprecipitations and GST-pulldowns were used to demonstrate a direct interaction between WWOX and SMAD3. Reporter assays, ChIP, confocal microscopy and in silico analyses were employed to determine the effect of WWOX silencing on TGFβ-signaling.
RESULTS
WWOX silencing affected cell proliferation, motility, attachment and deregulated expression of genes involved in cell cycle, motility and DNA damage. Interestingly, we detected an enrichment of targets activated by the SMAD3 transcription factor, including significant upregulation of ANGPTL4, FST, PTHLH and SERPINE1 transcripts. Importantly, we demonstrate that the WWOX protein physically interacts with SMAD3 via WW domain 1. Furthermore, WWOX expression dramatically decreases SMAD3 occupancy at the ANGPTL4 and SERPINE1 promoters and significantly quenches activation of a TGFβ responsive reporter. Additionally, WWOX expression leads to redistribution of SMAD3 from the nuclear to the cytoplasmic compartment. Since the TGFβ target ANGPTL4 plays a key role in lung metastasis development, we performed a meta-analysis of ANGPTL4 expression relative to WWOX in microarray datasets from breast carcinomas. We observed a significant inverse correlation between WWOX and ANGPTL4. Furthermore, the WWOX(lo)/ANGPTL4(hi) cluster of breast tumors is enriched in triple-negative and basal-like sub-types. Tumors with this gene expression signature could represent candidates for anti-TGFβ targeted therapies.
CONCLUSIONS
We show for the first time that WWOX modulates SMAD3 signaling in breast cells via direct WW-domain mediated binding and potential cytoplasmic sequestration of SMAD3 protein. Since loss of WWOX expression increases with breast cancer progression and it behaves as an inhibitor of SMAD3 transcriptional activity these observations may help explain, at least in part, the paradoxical pro-tumorigenic effects of TGFβ signaling in advanced breast cancer.
Publication
Journal: Birth Defects Research Part C - Embryo Today: Reviews
April/10/2014
Abstract
Articular cartilage is classified as permanent hyaline cartilage and has significant differences in structure, extracelluar matrix components, gene expression profile, and mechanical property from transient hyaline cartilage found in the epiphyseal growth plate. In the process of synovial joint development, articular cartilage originates from the interzone, developing at the edge of the cartilaginous anlagen, and establishes zonal structure over time and supports smooth movement of the synovial joint through life. The cascade actions of key regulators, such as Wnts, GDF5, Erg, and PTHLH, coordinate sequential steps of articular cartilage formation. Articular chondrocytes are restrictedly controlled not to differentiate into a hypertrophic stage by autocrine and paracrine factors and extracellular matrix microenvironment, but retain potential to undergo hypertrophy. The basal calcified zone of articular cartilage is connected with subchondral bone, but not invaded by blood vessels nor replaced by bone, which is highly contrasted with the growth plate. Articular cartilage has limited regenerative capacity, but likely possesses and potentially uses intrinsic stem cell source in the superficial layer, Ranvier's groove, the intra-articular tissues such as synovium and fat pad, and marrow below the subchondral bone. Considering the biological views on articular cartilage, several important points are raised for regeneration of articular cartilage. We should evaluate the nature of regenerated cartilage as permanent hyaline cartilage and not just hyaline cartilage. We should study how a hypertrophic phenotype of transplanted cells can be lastingly suppressed in regenerating tissue. Furthermore, we should develop the methods and reagents to activate recruitment of intrinsic stem/progenitor cells into the damaged site.
Publication
Journal: Cell Reports
November/13/2018
Abstract
Striatal locally projecting neurons, or interneurons, act on nearby circuits and shape functional output to the rest of the basal ganglia. We performed single-cell RNA sequencing of striatal cells enriching for interneurons. We find seven discrete interneuron types, six of which are GABAergic. In addition to providing specific markers for the populations previously described, including those expressing Sst/Npy, Th, Npy without Sst, and Chat, we identify two small populations of cells expressing Cck with or without Vip. Surprisingly, the Pvalb-expressing cells do not constitute a discrete cluster but rather are part of a larger group of cells expressing Pthlh with a spatial gradient of Pvalb expression. Using PatchSeq, we show that Pthlh cells exhibit a continuum of electrophysiological properties correlated with expression of Pvalb. Furthermore, we find significant molecular differences that correlate with differences in electrophysiological properties between Pvalb-expressing cells of the striatum and those of the cortex.
Publication
Journal: BMC Genomics
October/18/2016
Abstract
BACKGROUND
Clinical and subclinical endometritis are known to affect the fertility of dairy cows by inducing uterine inflammation. We hypothesized that clinical or subclinical endometritis could affect the fertility of cows by disturbing the molecular milieu of the uterine environment. Here we aimed to investigate the endometrial molecular signatures and pathways affected by clinical and subclinical endometritis. For this, Holstein Frisian cows at 42-60 days postpartum were classified as healthy (HE), subclinical endometritis (SE) or clinical endometritis (CE) based on veterinary clinical examination of the animals and histological evaluation the corresponding endometrial biopsies. Endometrial transcriptome and miRNome profile changes and associated molecular pathways induced by subclinical or clinical endometritis were then investigated using GeneChip® Bovine Genome Array and Exiqon microRNA PCR Human Panel arrays, respectively. The results were further validated in vitro using endometrial stromal and epithelial cells challenged with subclinical and clinical doses of lipopolysaccharide (LPS).
RESULTS
Transcriptome profile analysis revealed altered expression level of 203 genes in CE compared to HE animals. Of these, 92 genes including PTHLH, INHBA, DAPL1 and SERPINA1 were significantly upregulated, whereas the expression level of 111 genes including MAOB, CXCR4, HSD11B and, BOLA, were significantly downregulated in CE compared to the HE animal group. However, in SE group, the expression patterns of only 28 genes were found to be significantly altered, of which 26 genes including PTHLH, INHBA, DAPL1, MAOB, CXCR4 and TGIF1 were common to the CE group. Gene annotation analysis indicated the immune system processes; G-protein coupled receptor signaling pathway and chemotaxis to be among the affected functions in endometritis animal groups. In addition, miRNA expression analysis indicated the dysregulation of 35 miRNAs including miR-608, miR-526b* and miR-1265 in CE animals and 102 miRNAs including let-7 family (let-7a, let-7c, let-7d, let-7d*, let-7e, let-7f, let-7i) in SE animals. Interestingly, 14 miRNAs including let-7e, miR-92b, miR-337-3p, let-7f and miR-145 were affected in both SE and CE animal groups. Further in vitro analysis of selected differentially expressed genes and miRNAs in endometrial stroma and epithelial cells challenged with SE and CE doses of LPS showed similar results to that of the array data generated using samples collected from SE and CE animals.
CONCLUSIONS
The results of this study unraveled endometrial transcriptome and miRNome profile alterations in cows affected by subclinical or clinical endometritis which may have a significant effect on the uterine homeostasis and uterine receptivity.
Publication
Journal: Blood
August/20/2013
Abstract
Adult T-cell leukemia/lymphoma (ATL) is etiologically linked to infection with the human T-cell leukemia/lymphoma virus type 1 (HTLV-I). ATL is classified into 4 distinct clinical diseases: acute, lymphoma, chronic, and smoldering. Acute ATL is the most aggressive form, representing 60% of cases and has a 4-year survival of < 5%. A frequent complication and cause of death in acute ATL patients is the presence of lytic bone lesions and hypercalcemia. We analyzed the Wnt/β-catenin pathway because of its common role in cancer and bone remodeling. Our study demonstrated that ATL cells do not express high levels of β-catenin but displayed high levels of LEF-1/TCF genes along with elevated levels of β-catenin (LEF-1/TCF target genes) responsive genes. By profiling Wnt gene expression, we discovered that ATL patient leukemia cells shifted expression toward the noncanonical Wnt pathway. Interestingly, ATL cells overexpressed the osteolytic-associated genes-Wnt5a, PTHLH, and RANKL. We further show that Wnt5a secreted by ATL cells favors osteoclast differentiation and expression of RANK. Our results suggest that Wnt5a is a major contributing factor to the increase in osteolytic bone lesions and hypercalcemia found in ATL patients. Anti-Wnt5a therapy may prevent or reduce osteolytic lesions found in ATL patients and improve therapy outcome.
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