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Hirohiko Kamiyama,
Sherri Rauenzahn,
Joong Sup Shim,
Collins Karikari,
Georg Feldmann,
Li Hua,
Mihoko Kamiyama,
William Schuler,
Ming-Tseh Lin, Robert Beaty, [......],
Guanglan Mo,
Manuel Hidalgo,
Elizabeth M Jaffee,
Ralph H Hruban,
H A Jinnah,
Richard B S Roden,
Antonio Jimeno,
Jun O Liu,
Anirban Maitra,
James R Eshleman
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ABSTRACT: PURPOSE: High-throughput chemosensitivity testing of low-passage cancer cell lines can be used to prioritize agents for personalized chemotherapy. However, generating cell lines from primary cancers is difficult, because contaminating stromal cells overgrow the malignant cells. EXPERIMENTAL DESIGN: We produced a series of hypoxanthine phosphoribosyl transferase (hprt)-null immunodeficient mice. During growth of human cancers in these mice, hprt-null murine stromal cells replace their human counterparts. RESULTS: Pancreatic and ovarian cancers explanted from these mice were grown in selection media to produce pure human cancer cell lines. We screened one cell line with a 3,131-drug panel and identified seventy-seven FDA approved drugs with activity, including two novel drugs to which the cell line was uniquely sensitive. Xenografts of this carcinoma were selectively responsive to both drugs. CONCLUSIONS: Chemotherapy can be personalized using patient-specific cell lines derived in biochemically selectable mice.
Clinical Cancer Research 01/2013; · 7.74 Impact Factor
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G Feldmann,
N Habbe,
S Dhara,
S Bisht,
H Alvarez,
V Fendrich, R Beaty,
M Mullendore,
C Karikari,
N Bardeesy,
M M Ouellette,
W Yu,
A Maitra
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ABSTRACT: Pancreatic cancer is among the most dismal of human malignancies. Current therapeutic strategies are virtually ineffective in controlling advanced, metastatic disease. Recent evidence suggests that the Hedgehog signalling pathway is aberrantly reactivated in the majority of pancreatic cancers, and that Hedgehog blockade has the potential to prevent disease progression and metastatic spread.
Here it is shown that the Hedgehog pathway is activated in the Pdx1-Cre;LsL-Kras(G12D);Ink4a/Arf(lox/lox) transgenic mouse model of pancreatic cancer. The effect of Hedgehog pathway inhibition on survival was determined by continuous application of the small molecule cyclopamine, a smoothened antagonist. Microarray analysis was performed on non-malignant human pancreatic ductal cells overexpressing Gli1 in order to screen for downstream Hedgehog target genes likely to be involved in pancreatic cancer progression.
Hedgehog inhibition with cyclopamine significantly prolonged median survival in the transgenic mouse model used here (67 vs 61 days; p = 0.026). In vitro data indicated that Hedgehog activation might at least in part be ascribed to oncogenic Kras signalling. Microarray analysis identified 26 potential Hedgehog target genes that had previously been found to be overexpressed in pancreatic cancer. Five of them, BIRC3, COL11A1, NNMT, PLAU and TGM2, had been described as upregulated in more than one global gene expression analysis before.
This study provides another line of evidence that Hedgehog signalling is a valid target for the development of novel therapeutics for pancreatic cancer that might be worth evaluating soon in a clinical setting.
Gut 06/2008; 57(10):1420-30. · 10.11 Impact Factor
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Hector Alvarez,
Alejandro Corvalan,
Juan C Roa,
Pedram Argani,
Francisco Murillo,
Jennifer Edwards, Robert Beaty,
Georg Feldmann,
Seung-Mo Hong,
Michael Mullendore,
Ivan Roa,
Luis Ibañez,
Fernando Pimentel,
Alfonso Diaz,
Gregory J Riggins,
Anirban Maitra
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ABSTRACT: Gallbladder cancer (GBC) is an uncommon neoplasm in the United States, but one with high mortality rates. This malignancy remains largely understudied at the molecular level such that few targeted therapies or predictive biomarkers exist.
We built the first series of serial analysis of gene expression (SAGE) libraries from GBC and nonneoplastic gallbladder mucosa, composed of 21-bp long-SAGE tags. SAGE libraries were generated from three stage-matched GBC patients (representing Hispanic/Latino, Native American, and Caucasian ethnicities, respectively) and one histologically alithiasic gallbladder. Real-time quantitative PCR was done on microdissected epithelium from five matched GBC and corresponding nonneoplastic gallbladder mucosa. Immunohistochemical analysis was done on a panel of 182 archival GBC in high-throughput tissue microarray format.
SAGE tags corresponding to connective tissue growth factor (CTGF) transcripts were identified as differentially overexpressed in all pairwise comparisons of GBC (P < 0.001). Real-time quantitative PCR confirmed significant overexpression of CTGF transcripts in microdissected primary GBC (P < 0.05), but not in metastatic GBC, compared with nonneoplastic gallbladder epithelium. By immunohistochemistry, 66 of 182 (36%) GBC had high CTGF antigen labeling, which was significantly associated with better survival on univariate analysis (P = 0.0069, log-rank test).
An unbiased analysis of the GBC transcriptome by SAGE has identified CTGF expression as a predictive biomarker of favorable prognosis in this malignancy. The SAGE libraries from GBC and nonneoplastic gallbladder mucosa are publicly available at the Cancer Genome Anatomy Project web site and should facilitate much needed research into this lethal neoplasm.
Clinical Cancer Research 05/2008; 14(9):2631-8. · 7.74 Impact Factor
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Georg Feldmann,
Surajit Dhara,
Volker Fendrich,
Djahida Bedja, Robert Beaty,
Michael Mullendore,
Collins Karikari,
Hector Alvarez,
Christine Iacobuzio-Donahue,
Antonio Jimeno,
Kathleen L Gabrielson,
William Matsui,
Anirban Maitra
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ABSTRACT: In the context of pancreatic cancer, metastasis remains the most critical determinant of resectability, and hence survival. The objective of this study was to determine whether Hedgehog (Hh) signaling plays a role in pancreatic cancer invasion and metastasis because this is likely to have profound clinical implications. In pancreatic cancer cell lines, Hh inhibition with cyclopamine resulted in down-regulation of snail and up-regulation of E-cadherin, consistent with inhibition of epithelial-to-mesenchymal transition, and was mirrored by a striking reduction of in vitro invasive capacity (P < 0.0001). Conversely, Gli1 overexpression in immortalized human pancreatic ductal epithelial cells led to a markedly invasive phenotype (P < 0.0001) and near total down-regulation of E-cadherin. In an orthotopic xenograft model, cyclopamine profoundly inhibited metastatic spread; only one of seven cyclopamine-treated mice developed pulmonary micrometastases versus seven of seven mice with multiple macrometastases in control animals. Combination of gemcitabine and cyclopamine completely abrogated metastases while also significantly reducing the size of "primary" tumors. Gli1 levels were up-regulated in tissue samples of metastatic human pancreatic cancer samples compared with matched primary tumors. Aldehyde dehydrogenase (ALDH) overexpression is characteristic for both hematopoietic progenitors and leukemic stem cells; cyclopamine preferentially reduced "ALDH-high" cells by approximately 3-fold (P = 0.048). We confirm pharmacologic Hh pathway inhibition as a valid therapeutic strategy for pancreatic cancer and show for the first time its particular efficacy against metastatic spread. By targeting specific cellular subpopulations likely involved in tumor initiation at metastatic sites, Hh inhibitors may provide a new paradigm for therapy of disseminated malignancies, particularly when used in combination with conventional antimetabolites that reduce "bulk" tumor size.
Cancer Research 03/2007; 67(5):2187-96. · 7.86 Impact Factor
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ABSTRACT: Recent evidence suggests that noninvasive precursor lesions, classified as pancreatic intraepithelial neoplasia (PanIN), can progress to invasive pancreatic cancer. This review will discuss the major genetic alterations in PanIN lesions.
A comprehensive review of the literature was performed in order to find studies on the molecular profile of human PanIN lesions. In addition, recent publications on genetically engineered mouse models of preinvasive neoplasia and pancreatic cancers were reviewed.
PanINs demonstrate abnormalities at the genomic (DNA), transcriptomic (RNA), and proteomic levels, and there is a progressive accumulation of molecular alterations that accompany the histological progression from low-grade PanIN-1A to high-grade PanIN-3 lesions. Molecular changes in PanINs can be classified as "early" (KRAS2 mutations, telomere shortening, p21(WAF1/CIP1) up-regulation, etc.), "intermediate" (cyclin D1 up-regulation, expression of proliferation antigens, etc.), or "late" (BRCA2 and TP53 mutations, DPC4/SMAD4/MADH4 inactivation, etc.). All the genetic changes observed in PanINs are also found in invasive ductal adenocarcinomas, where they usually occur at a higher frequency. Genetically engineered mice expressing mutant Kras in the pancreas, with or without additional genetic alterations, provide a unique in vivo platform to study the pancreatic cancer progression model.
Molecular studies have been instrumental in establishing that PanIN lesions are the noninvasive precursors for invasive ductal adenocarcinomas. The availability of molecular date provides the basis for designing rational early detection strategies and therapeutic intervention trials before pancreatic neoplasms invade, with the intention of alleviating the dismal prognosis associated with this disease.
Journal of Hepato-Biliary-Pancreatic Surgery 02/2007; 14(3):224-32. · 1.60 Impact Factor
