Gene expression profiles of serous, endometrioid, and clear cell subtypes of ovarian and endometrial cancer.

PURPOSE: The presence of similar histologic subtypes of epithelial ovarian and endometrial cancers has long been noted, although the relevance of this finding to pathogenesis and clinical management is unclear. Despite similar clinical characteristics, histologic subtypes of cancers of the ovary and endometrium are treated according to organ of origin. This study compares the gene expression profiles of analogous histologic subtypes of cancers of the ovary and endometrium using the same genomic platform to determine the similarities and differences between these tumors. EXPERIMENTAL DESIGN: Gene expression profiles of 75 cancers (endometrioid, serous, and clear cell) of the ovary and endometrium, five renal clear cell cancers, and seven normal epithelial brushings were determined using a 11,000-element cDNA array. All images were analyzed using BRB ArrayTools. Validation was done using real-time PCR on select genes and immunohistochemical staining. RESULTS: Comparison across endometrial and ovarian cancers and serous and endometrioid tumors showed expression patterns reflecting their organ of origin. Clear cell tumors, however, showed remarkably similar expression patterns regardless of their origin, even when compared with renal clear cell samples. A set of 43 genes was common to comparisons of each of the three histologic subtypes of ovarian cancer with normal ovarian surface epithelium. CONCLUSIONS: The comparison of the gene expression profiles of endometrioid and serous subtypes of ovarian and endometrial cancer are largely unique to the combination of a particular subtype in a specific organ. In contrast, clear cell cancers show a remarkable similarity in gene expression profiles across organs (including kidney) and could not be statistically distinguished.     

Changes in microRNA expression levels correlate with clinicopathological features and prognoses in endometrial serous adenocarcinomas

This study aimed to determine the expression profiles of microRNAs (miRNAs) in endometrial serous adenocarcinoma and to examine the association between miRNA expression and clinical outcomes. Twenty‐one patients diagnosed with endometrial serous adenocarcinoma between January 2001 and December 2006 were enrolled. miRNA expression profiles were examined using miRNA microarray and qRT‐PCR. miRNA expression levels were correlated with clinicopathological variables and survival rates. A total of 120 miRNAs were differentially expressed in endometrial serous adenocarcinoma compared to normal endometria. Of these, 54 miRNAs were down‐regulated (>2‐fold), including miR‐101, miR‐10b*, miR‐152, and miR‐29b, and the remainder were up‐regulated (>2‐fold), including miR‐200a, miR‐200b, and miR‐205. Decreased expression of miR‐10b*, miR‐29b, and miR‐455‐5p was correlated with vascular invasion (P = 0.048, P = 0.013, and P = 0.032, respectively). Univariate analysis revealed that lower expression of miR‐101, miR‐10b*, miR‐139‐5p, miR‐152, miR‐29b, and miR‐455‐5p was significantly correlated with poor overall survival (P < 0.05), and reduced expression of miR‐152, miR‐29b, and miR‐455‐5p was significantly correlated with poor disease‐free survival (P < 0.05). Multivariate analysis demonstrated that decreased expression of miR‐152 (P = 0.021) was a statistically independent risk factor for overall survival, and decreased expression levels of miR‐101 (P = 0.016) and miR‐152 (P = 0.010) were statistically independent risk factors for disease‐free survival. In addition, transfection of miR‐101 or miR‐152 precursors into an endometrial serous carcinoma cell line inhibited cell growth (P < 0.0001 and P = 0.01, respectively). Moreover, strong positive immunoreactivity of cyclooxygenase‐2 (COX‐2) was significantly correlated with down‐regulation of miR‐101 (P = 0.035). These findings suggest that the dysregulation of miRNAs is associated with the poor prognosis in endometrial serous adenocarcinoma patients. (Cancer Sci 2009)     

Whole genome expression profiling of advance stage papillary serous ovarian cancer reveals activated pathways

Ovarian cancer is the most lethal type of gynecologic cancer in the Western world. The high case fatality rate is due in part because most ovarian cancer patients present with advanced stage disease which is essentially incurable. In order to obtain a whole genome assessment of aberrant gene expression in advanced ovarian cancer, we used oligonucleotide microarrays comprising over 40,000 features to profile 37 advanced stage papillary serous primary carcinomas. We identified 1191 genes that were significantly (P < 0.001) differentially regulated between the ovarian cancer specimens and normal ovarian surface epithelium. The microarray data were validated using real time RT-PCR on 14 randomly selected differentially regulated genes. The list of differentially expressed genes includes ones that are involved in cell growth, differentiation, adhesion, apoptosis and migration. In addition, numerous genes whose function remains to be elucidated were also identified. The microarray data were imported into PathwayAssist software to identify signaling pathways involved in ovarian cancer tumorigenesis. Based on our expression results, a signaling pathway associated with tumor cell migration, spread and invasion was identified as being activated in advanced ovarian cancer. The data generated in this study represent a comprehensive list of genes aberrantly expressed in serous papillary ovarian adenocarcinoma and may be useful for the identification of potentially new and novel markers and therapeutic targets for ovarian cancer.     

Long non-coding RNA profiling links subgroup classification of endometrioid endometrial carcinomas with trithorax and polycomb complex aberrations

Background

Integrative analysis of endometrioid endometrial carcinoma (EEC) using multiple platforms has distinguished four molecular subgroups. However, the landscape of expressed long non-coding RNAs (lncRNA) and their role in charting EEC subgroups and determining clinical aggressiveness remain largely unknown.

Materials and Methods

We performed integrative analysis of lncRNAs in EEC using The Cancer Genome Atlas (TCGA) molecular RNAseq profiles of 191 primary tumors for which genomic data were also available. We established lncRNA subgroup classification, correlated it with chromatin modifying gene expression, and described correlations between our lncRNA classification and clinico-genomic tumor features.

Results

Using stringent criteria, we identified 1,931 expressed lncRNAs and predicted potential drivers through integrative analysis. Unsupervised clustering of lncRNA expression revealed three robust categories: basal-like, luminal-like and CTNNB1-enriched subgroups. Basal-like subgroup was enriched for aggressive tumors with higher pathological grade (p < 0.0001), TNM stage (p = 0.01), and somatic mutations in trithorax-group genes (MLL, MLL2 and MLL3); and it overexpressed polycomb genes EZH2 and CBX2. In contrast to the luminal-like subgroup, progesterone (PGR) and estrogen receptor (ESR1) genes were highly down-regulated in the EEC basal-like subgroup. Consistent with its enrichment for CTNNB1 mutations (69%), lncRNA profile of the CTNNB1-enriched EEC subgroup was highly similar to that of the CTNNB1-enriched liver cancer subgroup.

Conclusions

Our results reveal the utility of systematic characterization of clinically annotated EEC in three clinically relevant subgroups. They also highlight the convergence of aberrations in polycomb- and trithorax-group genes in aggressive basal EEC subtypes, providing a rationale for further investigation of epigenetic therapy in this setting.     

PTEN、p21ras在人子宫内膜腺癌组织中的表达及其意义

目的探讨PTEN基因、Ki-ras基因在子宫内膜腺癌中的表达及意义。方法采用免疫组织化学S-P法测定20例正常增生期子宫内膜、20例不典型增生子宫内膜及45例子宫内膜腺癌组织中的PTEN、p21ras蛋白表达。结果PTEN在正常子宫内膜、不典型增生和内膜腺癌中的阳性表达率逐渐降低,分别为95.0%、40.0%、31.1%。正常子宫内膜组织中的PTEN阳性表达率显著高于不典型增生和内膜腺癌(P<0.01)。p21ras蛋白在正常子宫内膜、不典型增生和子宫内膜腺癌中的阳性表达率分别为0、50.0%、64.4%,子宫内膜不典型增生和子宫内膜腺癌组均显著高于正常子宫内膜组(P<0.01)。PTEN与p21ras蛋白表达呈负相关(r=-0.303,P<0.05),且均与细胞分化程度显著相关(P<0.05)。结论1)PTEN、ki-ras基因在子宫内膜腺癌发生发展中起重要作用,PTEN是其发生的早期分子事件;2)PTEN、p21ras的蛋白表达与病理分级有关;3)在子宫内膜腺癌中PTEN与p21ras可能参与同一蛋白通路发挥生理作用。     

Loss of HLA class I and mismatch repair protein expression in sporadic endometrioid endometrial carcinomas

Tumor cells can escape from cytotoxic T-cell responses by downregulation of human leukocyte antigen (HLA) class I molecules expressed at the cell surface which has been associated with a deficient mismatch repair (MMR) system in colorectal carcinomas. Our study investigated the association between expression of MMR proteins and HLA class I in sporadic endometrioid endometrial carcinomas (EC). In a consecutively selected cohort of 486 EC patients, MMR proteins (MLH1, MSH2 and MSH6) and HLA class I (HLA-A, -B, -C or β(2) m) were investigated by immunohistochemistry. Expression levels of MMR proteins and HLA class I were compared between low-grade and high-grade ECs. HLA class I expression was compared between tumors with loss (negative immunostaining of ≥1 MMR protein) and expression of MMR proteins. Associations between previously determined numbers of intratumoral CD8(+) T-lymphocytes and expression of MMR proteins and HLA class I and the influence on survival was determined. ECs with loss of MMR protein expression (33.5%) more frequently have loss of HLA-B/C (37.3%), compared to ECs with MMR protein expression (25.5%, p = 0.007). Patients with loss of MMR proteins have a worse disease-specific survival compared to patients with expression (p = 0.039). CD8(+) T-lymphocytes have a positive influence on disease-free and disease-specific survival in the total EC cohort but not in patients with loss of MMR protein expression. In conclusion, our results indicate that loss of MMR protein expression is related to selective downregulation of HLA class I which contributes to immune escape in EC with an abnormal MMR system.     

Coordinate expression of Cdc25B and ER-alpha is frequent in low-grade endometrioid endometrial carcinoma but uncommon in high-grade endometrioid and nonendometrioid carcinomas

Overexpression of cdc25B, an important cell cycle regulator, has been shown to result in mammary gland hyperplasia in transgenic mice and to increase steroid hormone responsiveness as a direct coactivator of the estrogen receptor (ER). We investigated the potential role of cdc25B in the pathogenesis of endometrial carcinomas in conjunction with ER-alpha. We examined the expression of cdc25B and phosphorylated ER-alpha in 4 archived human specimens of normal endometrium; 7 endometrial hyperplasia with or without atypia; 32 endometrioid endometrial carcinoma (EEC), including 20 low-grade (grade 1) and 12 high-grade (grade 2 or 3) tumors; and 18 endometrial cancers with aggressive histological subtypes (uterine papillary serous carcinoma and clear cell carcinoma, UPSC/CCC) by immunohistochemistry with monoclonal antibodies. Expression of cdc25B and phosphorylated ER-alpha was increased in endometrial hyperplasia and atypical hyperplasia compared with normal secretory endometrium. Ninety percent (18 of 20) of the low-grade EEC expressed cdc25B at a high level, whereas only 42% (5 of 12) of the high-grade EEC did so (chi(2) = 8.7; P < 0.01). Sixty-five percent (13 of 20) of the low-grade EEC expressed phosphorylated ER-alpha at high levels, but only 17% (2 of 12) of high-grade EEC did so (chi(2) = 7.0; P < 0.01). Coordinate high-level expression of phosphorylated ER-alpha and cdc25B occurred in 65% (13 of 20) of low-grade EEC but in only 17% (2 of 12) of the high-grade EEC (chi(2) = 7.0; P < 0.01). In the UPSC/CCC tumors, only 22% (4 of 18) of the tumors expressed phosphorylated ER-alpha at high-levels. However, 83% (15 of 18) of these carcinomas showed high expression of cdc25B (chi(2) = 13.5; P < 0.01). The majority of the UPSC/CCC (15 of 18) did not show coordinate high expression of phosphorylated ER-alpha and cdc25B. Our findings show that in endometrial hyperplasia and low-grade EEC, coordinate increase in cdc25B and phosphorylated ER-alpha occurs. However, in UPSC/CCC, cdc25B is highly expressed without coordinate increase in phosphorylated ER-alpha. Cdc25B may play important roles in the development and progression of EEC and UPSC/CCC by different mechanisms.     

子宫内膜腺癌组织vasohibin的异常表达及其生物学意义

目的:探讨vasohibin基因在子宫内膜腺癌(EEC)中异常表达的机制及其临床意义。方法:收集正常增生期子宫内膜组织10例,分泌期子宫内膜组织10例,EEC组织49例。荧光定量PCR和蛋白质印迹方法检测上述组织中vasohibin基因的表达;甲基化PCR方法检测vasohibin基因启动子的甲基化。结果:EEC组织中vasohibin基因mRNA表达量为(2.35±0.55)×103 copy/μg RNA,明显低于PE〔(3.39±0.65)×103 copy/μgRNA,P<0.001〕和SE组织〔(3.22±0.74)×103 copy/μg RNA,P<0.001〕。EEC组织中vasohibin蛋白表达的相对含量(0.87±0.18)明显低于PE(1.12±0.13,P=0.002 5)和SE组织(1.09±0.21,P=0.007 4)。Vasohibin基因表达与EEC的组织学分级(P=0.106)、肌层浸润(P=0.086)、有无淋巴结转移(P=0.160)和手术病理分期(P=0.440)无关。部分EEC中存在vasohibin基因启动子甲基化。甲基化EEC组织中vasohibin基因mRN...