The dominant negative H-ras mutant, N116Y, suppresses growth of metastatic human pancreatic cancer cells in the liver of nude mice

Abstract

In pancreatic cancer, the mutation of c-K-ras is a critical event of tumor growth and metastasis. We have previously demonstrated a dominant negative effect of N116Y on the growth of pancreatic cancer cells. To evaluate the potential of N116Y for suppressing the metastatic growth of pancreatic tumor cells, we made a replication-deficient recombinant N116Y adenovirus driven by the carcinoembryonic antigen (CEA) promoter (Ad CEA-N116Y). We demonstrated that the expression of N116Y, growth inhibition, and apoptotic death induction were all specific to pancreatic cancer cell lines (PCI-35 and PCI-43) that were promoter positive, whereas no growth retardation was observed in human embryonic pancreas-derived cell line 1C3D3 after Ad CEA-

A combinatorial approach for selectively inducing programmed cell death in human pancreatic cancer cells

“…Additionally, liposome-mediated in vivo gene transfer of an AS K-ras expression plasmid in animals containing AsPC-1 tumor cells, which represents a peritoneal dissemination model of pancreatic cancer, significantly suppressed tumor development in the peritoneal cavity (9). An important role for K-ras in pancreatic cancer physiology is further suggested by the ability of the dominant negative H-ras mut, N116Y, to suppress pancreatic cancer cell growth in vitro and in vivo, including tumorigenesis and metastasis to the liver of nude mice (12,13). Although promising, these studies demonstrate that a single approach of inhibiting K-ras is not sufficient to completely eradicate pancreatic carcinoma cells (9)(10)(11)(12)(13).…”

Ras-dependent carbon metabolism and transformation in mouse fibroblasts

“…Various strategies for the downregulation of Ras pathway have been reported: treatment of antibodies to K-Ras (Cochet et al, 1999;Russell et al, 1999), incorporation of a dominantnegative K-Ras mutant into target cells (Takeuchi et al, 2000), expression of an antisense specific to K-ras (Monia et al, 1992;Kita et al, 1999), retroviral delivery of a ribozyme (Kijima et al, 2004), short interfering RNAs (Brummelkamp et al, 2002) and utilization of compounds able to block the Ras-Raf interaction (Kato-Stankiewicz et al, 2002). We developed a genetically defined experimental system that allowed us to show that expression of a GEF dominant-negative mutant (that we call GEF-DN) downregulates Ras activity both in vitro (Vanoni et al, 1999) and in vivo on the basis of morphology, anchorage-independent growth and reduction of Ras-dependent tumor formation in nude mice (Bossu' et al, 2000).…”

Therapy of human pancreatic carcinoma based on suppression of HMGA1 protein synthesis in preclinical models

“…[33][34][35][36] Another approach is to neutralize overexpressed oncogenes in malignant pancreatic cells, as in the case of H-ras blocked by an adenovirally transduced dominant-negative H-ras mutant. 37 In this study, we evaluated the efficacy of pancreatic cancer gene therapy based on suppression of HMGA1 protein synthesis. The rationale for this approach came from previous results showing that: (1) HMGA1 protein is overexpressed in pancreatic carcinoma but not in the pancreatic normal tissue; 18 (2) HMGA overexpression is crucial for neoplastic transformation since its block prevents thyroid cell transformation induced by the viral k-ras oncogene; 20,21 (3) that K-ras activation is an early and very frequent finding in ductal pancreatic carcinomas 38 and (4) that an adenovirus carrying the HMGA1 in an antisense orientation leads to the death of thyroid carcinoma cell lines, but not of normal thyroid cells that do not express the HMGA1 proteins.…”