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215


Proteomic analysis of global alteration of protein expression in squamous cell carcinoma of the esophagus

Zhou, Ge; Li, Hongmei; Gong, Yi; Zhao, Yingxin; Cheng, Jingke; Lee, Peng; Zhao, Yingming
Squamous cell carcinoma of the esophagus (ESCC), a major subtype of esophageal carcinoma, is one of the aggressive cancers with worst prognosis in the world. The dismal outcome of ESCC is attributed to multiple reasons including its aggressive nature, largely unknown molecular mechanism of its progression, and the lack of biomarkers for early detection and effective prediction of its clinical behavior. To identify proteins with prognostic and/or predictive value, we applied a proteomics strategy to quantify proteins differentially expressed in ESCC using matched samples of carcinoma and adjacent normal epithelial cells. The analysis led to identification of 28 proteins aberrantly expressed in cancer cells with changes of at least three-fold in ESCC relative to normal squamous epithelial cells. These changes represent functional alterations of essential proteins for normal cellular physiology, accounting for many cellular changes involved in development of ESCC, including cell transformation, loss of differentiation, tumor growth, apoptosis, tumor invasion, and cell metabolism. The differentially expressed proteins shed new insights on the mechanism of tumorigenesis and provide candidate biomarkers for early detection of ESCC
PMID: 16127732
ISSN: 1615-9853
CID: 57699

The androgen receptor directly targets the c-FLIP gene to promote the androgen-independent growth of prostate cancer cells

Gao, Shen; Lee, Peng; Wang, Hua; Gerald, William; Adler, Michael; Zhang, Liying; Wang, Yun-Fang; Wang, Zhengxin
Androgens provide survival signals to prostate epithelial cells, and androgen ablation induces apoptosis in the prostate gland. However, the molecular mechanisms of actions of the androgen-signaling pathway in these processes are not fully understood. Here, we report that androgens induced expression of the cellular FLIP (c-FLIP) gene, which is a potent inhibitor of Fas/FasL-mediated apoptosis. The androgen receptor (AR) was recruited to the promoter of the c-FLIP gene in the presence of androgens. We found that c-FLIP promoter contained multiple functional androgen response elements (AREs). In addition, we show that c-FLIP overexpression accelerated progression to androgen independence by inhibiting apoptosis in LNCaP prostate tumors implanted in nude mice. Our results suggest that AR affects survival and apoptosis of prostate cells through regulation of the c-FLIP gene in response to androgens
PMCID:1855294
PMID: 15731171
ISSN: 0888-8809
CID: 48747

EXPRESSION OF ANDROGEN RECEPTOR ASSOCIATED PROTEIN 55 (ARA55) IN THE DEVELOPING HUMAN FETAL PROSTATE

Cai, Guoping; Huang, Hongying; Shapiro, Ellen; Zhou, Holly; Yeh, Shuyuan; Melamed, Jonathan; Greco, M Alba; Lee, Peng
PURPOSE:: Development and differentiation of the human fetal prostate are androgen dependent and follow a specific pattern of solid bud-ductal morphogenesis, which involves stromal-epithelial interactions. Androgen receptor associated protein 55 (ARA55) an androgen receptor coactivator localized in stromal cells, binds to androgen receptor (AR) and regulates androgen receptor translocation and transcriptional activity. We investigated whether ARA55 has a role in human prostate development. MATERIALS AND METHODS:: ARA55 expression was examined in 25 human prostates from fetuses at gestational ages 10 to 40 weeks and compared to the expression of 34betaE12 (a basal cell marker), smooth muscle actin, desmin (a smooth muscle marker), vimentin (a mesenchymal marker) and Ki-67 (a proliferation marker) by immunohistochemistry. RESULTS:: Prostatic epithelium appeared as solid epithelial buds from the urogenital sinus. It underwent arborization and ductal differentiation from the center to the periphery. ARA55 was expressed in stromal cells with a zonal pattern, primarily in the peripheral zone surrounding the noncanalized acini. Most cells in solid buds were positive for 34betaE12, while only basal layer cells in the centrally located epithelial ducts stained with 34betaE12. Solid buds also had a higher proliferation index than ducts. In addition, ARA55 expressing stromal cells but not ARA55 negative stromal cells showed smooth muscle differentiation. CONCLUSIONS:: The intimate relationship between ARA55 expressing stromal cells and mitotically active, noncanalized acini suggests that ARA55 has a role in the stromal-epithelial interaction involved in fetal prostate development
PMID: 15879885
ISSN: 0022-5347
CID: 51801

Expression of progesterone receptor is a favorable prognostic marker in ovarian cancer

Lee, Peng; Rosen, Daniel G; Zhu, Changcheng; Silva, Elvio G; Liu, Jinsong
OBJECTIVE: Receptors for estrogen (ER), progesterone (PR), or androgen (AR) are predictive and prognostic markers of malignancy of multiple endocrine organs, including endometrial and breast cancer. However, the role of ERs, PRs, or ARs in the carcinogenesis of ovarian cancer, another sex hormone-dependent malignancy, is still controversial despite numerous studies that have attempted to determine their role. The disagreement in the findings may result from the fact that the numbers of tumor samples in studies have been small and that different immunohistochemical methods have been used that can introduce variation in the scoring of the histology. We therefore examined the pattern of expression of ERs, PRs, and ARs in a large number of samples of primary ovarian carcinoma by using a tissue microarray technique. METHODS: We constructed a tissue microarray with 322 samples of primary ovarian carcinoma obtained at surgery performed at The University of Texas M. D. Anderson Cancer Center between 1990 and 2000. Immunohistochemistry studies were performed by using the immunoperoxidase technique against primary antibodies (ER, PR, and AR). RESULTS: ERs, PRs, and ARs were differently expressed in different histotypes of ovarian cancer: ERs were expressed in 77.3% of all cases but more highly expressed in serous and endometrioid types; PRs were expressed in 26.2% of all cases but most highly expressed in the endometrioid type < 64.2%; and ARs were expressed in 43.7% of all cases but were most highly expressed in serous (47.5%) carcinomas. Of particular importance, the expression of PRs, but not ERs or ARs, was associated with better survival (P < 0.0001) in univariate and multivariate analyses. CONCLUSIONS: The PR is an independent marker, with its overexpression associated with a favorable prognosis in women with ovarian cancer
PMID: 15721410
ISSN: 0090-8258
CID: 48222

Adenomatoid tumor of the adrenal gland: A clinicopathologic study of 3 cases [Case Report]

Garg, Karuna; Lee, Peng; Ro, J Y; Qu, Zhenhong; Troncoso, Patricia; Ayala, Alberto G
Abstract Adenomatoid tumors are relatively uncommon benign neoplasms of mesothelial origin, usually occurring in the male and female genital tracts. Rare extragenital adenomatoid tumors have been identified in the adrenal glands, heart, mesentery, pleura, and lymph nodes. In the adrenal gland, adenomatoid tumors may pose a diagnostic challenge. The differential diagnosis includes adrenocortical carcinoma and metastatic carcinoma, especially signet ring cell carcinoma. Because of its glandular pattern, an adenomatoid tumor may be confused with an adenocarcinoma. We present 3 cases of adrenal adenomatoid tumors, including one with a concurrent large hemorrhagic vascular adrenal cyst. The adenomatoid tumors were unilateral, appeared solid and white, and varied from 1.7 to 4.2 cm in diameter. They occurred in 3 male patients aged 33, 33, and 46 years. One patient presented with abdominal pain due to the presence of a concurrent large adrenal cyst. The tumor was an incidental radiological finding in another case and was discovered during the course of a workup for hypertension in the third case. The light microscopic appearances were consistent with those of typical adenomatoid tumors. Immunohistochemical stains for calretinin and cytokeratin 5/6 were positive, confirming the tumors' mesothelial origin. Ultrastructural studies performed in 2 cases revealed microvilli and desmosomes. Follow-up showed no evidence of recurrence or metastasis. In our experience, the key to the diagnosis of this rare benign tumor is to consider adenomatoid tumor in the differential diagnosis of any glandular tumor occurring in the adrenal gland
PMID: 15692945
ISSN: 1092-9134
CID: 48054

Upregulated expression of androgen receptor (AR) specific transcription corepressors in prostate cancer [Meeting Abstract]

Zhang, XM; Chiu, J; Kong, XT; Melamed, J; Twiss, C; Lee, P
ISI:000226238600804
ISSN: 0023-6837
CID: 50462

Decreased expression of PRMT5 is associated with prostate cancer [Meeting Abstract]

Guo, CC; Zhang, X; Yee, H; Chiriboga, L; Melamed, J; Lee, P
ISI:000226117900660
ISSN: 0893-3952
CID: 50431

Decreased expression of PRMT5 is associated with prostate cancer [Meeting Abstract]

Guo, CC; Zhang, X; Yee, H; Chiriboga, L; Melamed, J; Lee, P
ISI:000226238600660
ISSN: 0023-6837
CID: 50460

Expression of mucin antigens in renal tumors [Meeting Abstract]

Guo, CC; Kong, X; Lee, P; Melamed, J
ISI:000226238600659
ISSN: 0023-6837
CID: 50459

Expression of mucin antigens in renal tumors [Meeting Abstract]

Guo, CC; Kong, X; Lee, P; Melamed, J
ISI:000226117900659
ISSN: 0893-3952
CID: 50430