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221


Expression of insulin-like growth factors (IGFs) and IGF signaling: molecular complexity in uterine leiomyomas

Peng, Lan; Wen, Yong; Han, Yulong; Wei, Anran; Shi, Guizhi; Mizuguchi, Masashi; Lee, Peng; Hernando, Eva; Mittal, Khush; Wei, Jian-Jun
OBJECTIVE: To study whether dysregulation of insulin-like growth factors (IGFs) and IGF signaling are common molecular changes in symptomatic leiomyomas (fibroids) and whether IGFs are associated with large fibroids. DESIGN: Examination of IGFs and IGF pathway genes in a large cohort of fibroids at transcriptional and translational levels. Mechanisms leading to alterations of IGFs and related genes were also analyzed. SETTING: University clinical research laboratory. PATIENT(S): Hysterectomies for symptomatic fibroids were collected: 180 cases from paraffin-embedded tissues and 50 cases from fresh-frozen tissues. INTERVENTION(S): Tissue microarray and immunohistochemistry, DNA methylation analysis, reverse-transcriptase polymerase chain reaction, and Western blot. MAIN OUTCOME MEASUREMENT(S): Transcription and translation analyses of IGF-1/2, p-AKT, p-S6K, and TSC1/2 in fibroids and matched myometrium. RESULT(S): Insulin-like growth factors and downstream effectors were dysregulated in approximately one third of fibroids. All except for IGF-2 seemed to be abnormally regulated at translation levels. Up-regulation of IGF-2 messenger RNAs was contributed by all four alternating slicing promoters. There was a positive correlation of IGF-1 and p-AKT over-expression with fibroid size. Insulin-like growth factor 1 but not IGF-2 levels directly correlated with activation of p-AKT and p-S6K. CONCLUSION(S): Altered expressions of IGFs and their related downstream proteins were found in one third of fibroids. Large fibroids show high levels of IGF-1 and p-AKT activity compared with small ones
PMID: 18439583
ISSN: 1556-5653
CID: 78574

Aberrant miR-182 expression promotes melanoma metastasis by repressing FOXO3 and microphthalmia-associated transcription factor

Segura, Miguel F; Hanniford, Douglas; Menendez, Silvia; Reavie, Linsey; Zou, Xuanyi; Alvarez-Diaz, Silvia; Zakrzewski, Jan; Blochin, Elen; Rose, Amy; Bogunovic, Dusan; Polsky, David; Wei, Jianjun; Lee, Peng; Belitskaya-Levy, Ilana; Bhardwaj, Nina; Osman, Iman; Hernando, Eva
The highly aggressive character of melanoma makes it an excellent model for probing the mechanisms underlying metastasis, which remains one of the most difficult challenges in treating cancer. We find that miR-182, member of a miRNA cluster in a chromosomal locus (7q31-34) frequently amplified in melanoma, is commonly up-regulated in human melanoma cell lines and tissue samples; this up-regulation correlates with gene copy number in a subset of melanoma cell lines. Moreover, miR-182 ectopic expression stimulates migration of melanoma cells in vitro and their metastatic potential in vivo, whereas miR-182 down-regulation impedes invasion and triggers apoptosis. We further show that miR-182 over-expression promotes migration and survival by directly repressing microphthalmia-associated transcription factor-M and FOXO3, whereas enhanced expression of either microphthalmia-associated transcription factor-M or FOXO3 blocks miR-182's proinvasive effects. In human tissues, expression of miR-182 increases with progression from primary to metastatic melanoma and inversely correlates with FOXO3 and microphthalmia-associated transcription factor levels. Our data provide a mechanism for invasion and survival in melanoma that could prove applicable to metastasis of other cancers and suggest that miRNA silencing may be a worthwhile therapeutic strategy
PMCID:2634798
PMID: 19188590
ISSN: 1091-6490
CID: 92154

Pancreatic carcinoma with multilineage (acinar, neuroendocrine, and ductal) differentiation

Newman, Kia; Stahl-Herz, Jay; Kabiawu, Oluyomi; Newman, Elliot; Wieczorek, Rosemary; Wang, Beverly; Pei, Zhiheng; Bannan, Michael; Lee, Peng; Xu, Ruliang
The preponderance of pancreatic tumors is adenocarcinoma of the ductal type; carcinomas with multiple lineage differentiation are extremely rare. We report an unusual case of pancreatic carcinoma with combined acinar and neuroendocrine differentiation and minor ductal component with concurrent acinar-ductal metaplasia (ADM), an early lesion implicated in ductal carcinogenesis. The patient is a 56-year-old man with vague complaints of dull left upper quadrant pain with radiation across the mid-portion of his abdomen. A computer tomography scan revealed an irregular enlargement of the distal 3.2 cm of the pancreatic body. A distal pancreatectomy was then performed. Histologic examination revealed a pancreatic carcinoma with cellular features of eosinophilic granular cytoplasm and salt-pepper nuclei. The acinar differentiation of the carcinoma was confirmed by positivity on periodic acid-Schiff stain resistant to diastase digestion (dPAS), positivity for antitrypsin on immunohistochemistry (IHC), and presence of zymogen granules on electron microscopy (EM). The neuroendocrine differentiation was evident by positive synaptophysin and chromogranin stain on IHC and neuroendocrine granules on EM. The ductal component was only visible by PAS stain and immunostains for CEA and CK19A and accompanied by a number of the acinar-ductal metaplasia lesions adjacent to the main tumor. Thus, the histological, histochemical, immunohistochemical and electron-microscopic evidence all suggested that the pancreatic carcinoma underwent trilineage differentiation
PMCID:2713457
PMID: 19636408
ISSN: 1936-2625
CID: 101289

CHARACTERIZATION AND INCIDENCE OF STROKE IN FABRY DISEA [Meeting Abstract]

Sims, K; Politei, J; Banikazemi, M; Lee, P
ISI:000268348900023
ISSN: 0149-2918
CID: 101312

Lef1 Expression in Androgen-Independent Prostate Cancer [Meeting Abstract]

Zhang, M; Li, YR; Wang, LG; Melamed, J; Liu, XM; Wei, JJ; Peng, Y; Pellicer, A; Garabedian, MJ; Ferrari, A; Lee, P
ISI:000262486300922
ISSN: 0023-6837
CID: 104576

Lef1 Expression in Androgen-Independent Prostate Cancer [Meeting Abstract]

Zhang, M; Li, YR; Wang, LG; Melamed, J; Liu, XM; Wei, JJ; Peng, Y; Pellicer, A; Garabedian, MJ; Ferrari, A; Lee, P
ISI:000262371500922
ISSN: 0893-3952
CID: 104577

Proteomics, Pathway Array and Signaling Network-Based Medicine in Cancer

Zhang, David Y; Ye, Fei; Gao, Ling; Liu, Xiaoliang; Zhao, Xin; Che, Yufang; Wang, Hongxia; Wang, Libo; Wu, Josephine; Song, Dong; Liu, Wei; Xu, Hong; Jiang, Bo; Zhang, Weijia; Wang, Jinhua; Lee, Peng
ABSTRACT: Cancer is a multifaceted disease that results from dysregulated normal cellular signaling networks caused by genetic, genomic and epigenetic alterations at cell or tissue levels. Uncovering the underlying protein signaling network changes, including cell cycle gene networks in cancer, aids in understanding the molecular mechanism of carcinogenesis and identifies the characteristic signaling network signatures unique for different cancers and specific cancer subtypes. The identified signatures can be used for cancer diagnosis, prognosis, and personalized treatment. During the past several decades, the available technology to study signaling networks has significantly evolved to include such platforms as genomic microarray (expression array, SNP array, CGH array, etc.) and proteomic analysis, which globally assesses genetic, epigenetic, and proteomic alterations in cancer. In this review, we compared Pathway Array analysis with other proteomic approaches in analyzing protein network involved in cancer and its utility serving as cancer biomarkers in diagnosis, prognosis and therapeutic target identification. With the advent of bioinformatics, constructing high complexity signaling networks is possible. As the use of signaling network-based cancer diagnosis, prognosis and treatment is anticipated in the near future, medical and scientific communities should be prepared to apply these techniques to further enhance personalized medicine
PMCID:2780394
PMID: 19863813
ISSN: 1747-1028
CID: 104874

Molecular mechanisms involving prostate cancer racial disparity

Hatcher, David; Daniels, Garrett; Osman, Iman; Lee, Peng
African American (AA) men with prostate cancer (PCa) have worse disease, with a higher incidence, younger age and more advanced disease at diagnosis, and a worse prognosis, compared to Caucasian (CA) men. In addition to socioeconomic factors and lifestyle differences, molecular alterations contribute to this discrepancy. In this review, we summarize molecular genetics research results interrelated with the biology of PCa racial disparity. Androgen and androgen receptor (AR) pathways have long been associated with prostate growth. Racial differences have also been found among variants of the genes of the enzymes involved in androgen biosynthesis and metabolism, such as SRD5A2, CYP17, and CYP3A4. The levels of expression and CAG repeat length of AR also show racial divergence and may be critical molecular alterations for racial disparity. Growth factors and their receptors, which promote cancer cell growth, are another potential cause of the disparity; both EGFR and EPHB2, two of the most studied receptors, show interethnic differences. Differences have also been found among genes regulating cell apoptosis, such as BCL2, which is increased in PCa in the AA population. Recent developments in genetics, proteomics, and genomics, among other molecular biotechnologies, will greatly aid the advancement of translational research on PCa racial disparity, hopefully culminating in the discovery of novel mechanisms of disease, in addition to prognostic markers and novel therapeutic approaches
PMCID:2776319
PMID: 19956434
ISSN: 1943-8141
CID: 105528

Activation of Stat3 in renal tumors

Guo, Charles; Yang, Guanyu; Khun, Kyle; Kong, Xiantian; Levy, David; Lee, Peng; Melamed, Jonathan
Signal transducer and activator of transcription 3 (Stat3) plays a vital role in signal transduction pathways that mediate transformation and inhibit apoptosis. Oncogenic Stat3 is persistently activated in several human cancers and transformed cell lines. Previous studies indicate activation of Stat3 in renal cell carcinoma (RCC). However, the detailed characterization of the Stat3 expression pattern in different histologic types of RCC is lacking. We have analyzed the immunoprofile of activated or phosphorylated Stat3 (pStat3) in a tissue microarray of renal tumors of different histologic types, including 42 cases of conventional clear cell type, 24 chromophobe, and 7 papillary, 15 oncocytoma, 7 urothelial carcinoma and 21 normal kidney tissues using an anti-pStat3 antibody (recognizes only activated STAT3). pStat3 nuclear staining was observed in 25 of 42 conventional clear cell RCC (59.5 %), 8 of 24 chromophobe RCC (33.3%), 4 of 7 papillary RCC (57.1%). In the other tumor groups, 4 of 15 oncocytomas (26.7%) and 6 of 7 urothelial carcinomas (85.7%) showed positive nuclear staining. Weak nuclear immunoreactivity for pStat3 was seen in 4 of 21 cases of non-neoplastic kidney tissue (19.0%). The extent of Stat3 activation as determined by nuclear expression of its phosphorylated form is increased in histologic types of renal tumors with greater malignant potential, specifically conventional clear cell RCC, papillary RCC and urothelial carcinoma, only slightly increased in chromophobe RCC, and not increased in oncocytoma. These results suggest a role of Stat3 activation in different types of renal neoplasia, possibly serving as a prognostic marker or therapeutic target
PMCID:2776322
PMID: 19956438
ISSN: 1943-8141
CID: 105529

Developing a multidisciplinary prospective melanoma biospecimen repository to advance translational research

Wich, Lindsay G; Hamilton, Heather K; Shapiro, Richard L; Pavlick, Anna; Berman, Russell S; Polsky, David; Goldberg, Judith D; Hernando, Eva; Manga, Prashiela; Krogsgaard, Michelle; Kamino, Hideko; Darvishian, Farbod; Lee, Peng; Orlow, Seth J; Ostrer, Harry; Bhardwaj, Nina; Osman, Iman
Several challenges face the development and operation of a biospecimen bank linked to clinical information, a critical component of any effective translational research program. Melanoma adds particular complexity and difficulty to such an endeavor considering the unique characteristics of this malignancy. We describe here a review of biospecimen bank and our experience in establishing a multi-disciplinary, prospective, integrated clinicopathological-biospecimen database in melanoma. The Interdisciplinary Melanoma Cooperative Group (IMCG), a prospective clinicopathological and biospecimen database, was established at the New York University (NYU) Langone Medical Center. With patients' informed consent, biospecimens from within and outside NYU, clinicopathological data, and follow-up information are collected using developed protocols. Information pertaining to biospecimens is recorded in 35 fields, and clinicopathological information is recorded in 371 fields within 5 modules in a virtual network system. Investigators conducting research utilizing the IMCG biospecimen resource are blind to clinicopathological information, and molecular data generated using biospecimens are linked independently with clinicopathological data by biostatistics investigators. This translational research enterprise acts as a valuable resource to efficiently translate laboratory discoveries to the clinic
PMCID:2776290
PMID: 19966936
ISSN: 1943-8141
CID: 105566