Transduction and Oncolytic Profile of a Potent Replication-Competent Adenovirus 11p Vector (RCAd11pGFP) in Colon Carcinoma Cells (original) (raw)
Related papers
2023
Purpose: A33 antigen is a membrane-bound protein expressed in intestinal epithelium that is overexpressed in 95% of primary and metastatic colorectal carcinomas but is absent in most epithelial tissues and tumor types. We hypothesized that A33 promoter might be useful in the design of a conditionally replicative adenovirus for the treatment of colorectal cancer (CRC). Experimental Design: We cloned an A33 promoter fragment (A33Pr) that extends from-105 to +307 bp. Using luciferase activity as a reporter gene, we showed that A33Pr was active in CRC cell lines. We next constructed a conditionally replicative adenovirus named AV22EL where E1A was placed under the control of A33Pr. The tumor-specific oncolytic effect of AV22EL was investigated both in vitro and in vivo. Results: AV22EL induced specific in vitro lysis of human CRC cell lines that expressed A33 and have negligible lytic capacity on cells that lacked or had minimal A33 expression, including normal human colonic cells. In vivo, a marked reduction of tumor growth and increased long-term survival rates were observed in nude mice xenografted with s.c. CRC tumors. Combination with 5-fluorouracil induced an additive effect in vitro with no toxic effects in vivo. Remarkably, AV22EL completely eliminated established hepatic metastases in >90% of mice and restored hepatic function according to biochemical parameters. Its systemic administration induced E1A expression only in the hepatic metastasis but not in normal organs. Conclusions: These data show that AV22EL is a stringently regulated and potent oncolytic agent for the treatment of CRC.
A Novel Chromogranin-A Promoter-Driven Oncolytic Adenovirus for Midgut Carcinoid Therapy
Clinical Cancer Research, 2007
Purpose: The use of replication-selective oncolytic adenoviruses is an emerging therapeutic approach for cancer, which thus far has not been employed for carcinoids.We therefore constructed Ad[CgA-E1A], a novel replication-selective oncolytic adenovirus, where the chromogranin A (CgA) promoter controls expression of the adenoviral E1A gene. Experimental Design: The Ad[CgA-E1A] virus was evaluated for E1A protein expression, replication ability, and cytolytic activity in various cell lines. It was also evaluated for treatment of xenografted human carcinoid tumors in nude mice. To use Ad[CgA-E1A] for the treatment of carcinoid liver metastases, it is important that normal hepatocytes do not support virus replication to minimize hepatotoxicity. We therefore evaluated CgA protein expression in normal hepatocytes. We also evaluated CgA gene expression in normal hepatocytes and microdissected tumor cells from carcinoid metastases. Results: We found that Ad[CgA-E1A] replicates similarly to wild-type virus in tumor cells with neuroendocrine features, including the BON carcinoid cell line and the SH-SY-5Y neuroblastoma cell lines, whereas it is attenuated in other cell types.Thus, cells where the CgA promoter is active are selectively killed. We also found that Ad[CgA-E1A] is able to suppress fast-growing human BON carcinoid tumors in nude mice. Furthermore, CgA is highly expressed in microdissected cells from carcinoid metastases, whereas it is not expressed in normal hepatocytes. Conclusion: Ad[CgA-E1A] is an interesting agent for the treatment of carcinoid liver metastases in conjunction with standard therapy for these malignancies.
Gene Therapy, 2005
Conditionally replicating adenoviruses (CRAds) selectively replicate in and thereby kill cancer cells. The CRAd AdD24 with pRb-binding-deficient E1A kills cancer cells efficiently. Arming CRAds with genes encoding prodrug-converting enzymes could allow for enhanced anticancer efficacy by the combined effects of oncolytic replication and local prodrug activation. Here, we investigated combination treatment of human colon cancer cell lines with AdD24-type CRAds and gene-directed enzyme prodrug therapy (GDEPT) using two different enzyme/prodrug systems, that is, thymidine kinase/ganciclovir (TK/GCV) and carboxylesterase (CE)/CPT-11. On all three cell lines tested, GDEPT with TK/GCV made CRAd treatment less efficacious. In contrast, expression of a secreted form of CE (sCE2) combined with CPT-11 treatment markedly enhanced the efficacy of AdD24 virotherapy. Based on this observation, we constructed an AdD24 variant expressing sCE2. In the absence of CPT-11, this new CRAd Ad5-D24.E3-sCE2 was similarly effective as its parent in killing human colon cancer cells. Low concentrations of CPT-11 inhibited Ad5-D24.E3-sCE2 propagation. Nevertheless, CPT-11 specifically augmented the cytotoxicity of Ad5-D24.E3-sCE2 against all three-colon cancer cell lines. Hence, the positive contribution of sCE2/CPT-11 GDEPT to colon cancer cytotoxicity outweighed its negative influence on CRAd propagation. Therefore, CRAd-sCE2/ CPT-11 combination therapy appears useful for more effective treatment of colon cancer.
Purpose: We decided to construct a novel oncolytic adenovirus whose replication was driven by the CDC25B promoter for its use in preclinical models of pancreatic cancer. Experimental Design: We placed the essential E1A gene under control of the CDC25B promoter. Based on preliminary data, we pseudotyped the adenovirus with a chimeric fiber of serotypes 5/3. We investigated the in vitro lytic effect and the in vivo therapeutic efficacy in combination with gemcitabine on human pancreatic tumor xenografts orthotopically growing in nude mice and in tumors growing in Syrian hamsters. We also assessed biochemical markers of hepatic toxicity and CA19.9 levels. Results: AV25CDC exhibited a strong in vitro lytic effect on pancreatic cancer cells. In vivo administration of AV25CDC combined with gemcitabine in mice harboring subcutaneously growing SW1990 pancreatic tumors almost abrogated tumor growth. Nude mice harboring 15-day-old orthotopic tumors, treated intratumorally or systemically with AV25CDC combined with gemcitabine, exhibited 70% to 80% reduction in tumor size compared with control mice that lasted for at least 60 days. Chemovirotherapy treatment induced a return to normal levels of biochemical parameters of hepatic toxicity; these mice exhibited more than 90% reduction in CA19.9 serum levels compared with control. Chemovirotherapy efficacy was confirmed in mice harboring Mia PaCa-2 tumors and in Syrian hamster harboring HaP-T1 tumors.Weobserved that viral treatment disrupted tumor architecture and induced an increase in MMP-9 activity that might facilitate gemcitabine penetrability. Conclusion: These data demonstrate that AV25CDC is an effective oncolytic agent candidate for pancreatic cancer chemovirotherapy combination. Clin Cancer Res; 1–10. 2014 AACR.
Molecular Therapy, 2004
Liver is the most preferential site for metastasis of colon cancer. We, in the present study, constructed a self-replicable adenovirus in which E1A is driven by a CEA promoter and E1B-55K is deleted from the E1B region (AdCEAp/Rep) and examined its effects on multiple metastases of a human colon cancer cell in a mouse xenograft model. We first showed effective replication of the virus in various CEAproducing human colon cancer cells (M7609, HT-29) and subsequent lysis of the infected cells in vitro. We then demonstrated that a single intratumoral injection of the virus (1 Â 10 8 PFU/100 Ml) induced a complete regression of subcutaneous tumors (M7609) inoculated into nude mice. Further, we demonstrated that systemic administration of the virus (1 Â 10 8 PFU/100 Ml) through the tail vein to nude mice, which 1 week prior had been inoculated with tumor cells (colon carcinoma cell line HT-29) via the spleen and showed apparent multiple metastases in the liver, effectively suppressed the metastasis formation. The mean survival time of the treated mice was significantly longer than that of the controls. Thus, the systemic administration of AdCEAp/Rep was considered to be effective on multiple liver metastases of CEA-positive colon cancer in a xenograft model.
Combined therapy of colon carcinomas with an oncolytic adenovirus and valproic acid
Oncotarget
The anti-tumor potential of oncolytic adenoviruses (CRAds) has been demonstrated in preclinical and clinical studies. While these agents failed to eradicate tumors when used as a monotherapy, they may be more effective if combined with conventional treatments such as radiotherapy or chemotherapy. This study seeks to evaluate the combination of a CRAd bearing a ∆24 deletion in E1A with valproic acid (VPA), a histone deacetylase inhibitor, for the treatment of human colon carcinomas. This combination led to a strong inhibition of cell growth both in vitro and in vivo compared to treatment with CRAd or VPA alone. This effect did not stem from a better CRAd replication and production in the presence of VPA. Inhibition of cell proliferation and cell death were induced by the combined treatment. Moreover, whereas cells treated only with CRAd displayed a polyploidy (> 4N population), this phenotype was increased in cells treated with both CRAd and VPA. In addition, the increase in polyploidy triggered by combined treatment with CRAd and VPA was associated with the enhancement of H2AX phosphorylation (γH2AX), a hallmark of DNA damage, but also with a decrease of several DNA repair proteins. Finally, viral replication (or E1A expression) was shown to play a key role in the observed effects since no enhancement of polyploidy nor increase in γH2AX were found following cell treatment with a replication-deficient Ad and VPA. Taken together, our results suggest that CRAd and VPA could be used in combination for the treatment of colon carcinomas.
Cancer Research, 2008
Genetic bioselection of a mutagenized Ad5wt stock in human tumor xenografts led us to isolate AdT1, a mutant displaying a large-plaque phenotype in vitro and an enhanced systemic antitumor activity in vivo. AdT1 phenotype correlates with an increased progeny release without affecting total viral yield in different human tumors and cancer-associated fibroblasts. An approach combining hybrid Ad5/AdT1 recombinants and sequencing identified a truncating insertion in the endoplasmic reticulum retention domain of the E3/19K protein (445A mutation) which relocates the protein to the plasma membrane and is responsible for AdT1's enhanced release. E3/19K-445A phenotype does not correlate with the protein's ability to interact with MHC-I or induce apoptosis. Intracellular calcium measurement revealed that the 445A mutation induces extracellular Ca 2+ influx, deregulating intracellular Ca 2+ homeostasis and inducing membrane permeabilization, a viroporin-like function. E3/19K-445A mutants also display enhanced antitumoral activity when injected both intratumorally and systemically in different models in vivo. Our results indicate that the inclusion of mutation 445A in tumor-selective adenoviruses would be a very powerful tool to enhance their antitumor efficacy. [Cancer Res 2008;68(21):8928-37]
Clinical Cancer Research, 2009
A33 antigen is a membrane-bound protein expressed in intestinal epithelium that is overexpressed in 95% of primary and metastatic colorectal carcinomas but is absent in most epithelial tissues and tumor types. We hypothesized that A33 promoter might be useful in the design of a conditionally replicative adenovirus for the treatment of colorectal cancer (CRC). Experimental Design: We cloned an A33 promoter fragment (A33Pr) that extends from-105 to +307 bp. Using luciferase activity as a reporter gene, we showed that A33 Pr was active in CRC cell lines. We next constructed a conditionally replicative adenovirus named AV22EL where E1A was placed under the control of A33Pr. The tumor-specific oncolytic effect of AV22EL was investigated both in vitro and in vivo. Results: AV22EL induced specific in vitro lysis of human CRC cell lines that expressed A33 and have negligible lytic capacity on cells that lacked or had minimal A33 expression, including normal human colonic cells. In vivo, a marked reduction of tumor growth and increased long-term survival rates were observed in nude mice xenografted with s.c. CRC tumors. Combination with 5-fluorouracil induced an additive effect in vitro with no toxic effects in vivo. Remarkably, AV22EL completely eliminated established hepatic metastases in >90% of mice and restored hepatic function according to biochemical parameters. Its systemic administration induced E1A expression only in the hepatic metastasis but not in normal organs. Conclusions: These data show that AV22EL is a stringently regulated and potent oncolytic agent for the treatment of CRC. Colorectal cancer (CRC) is the second most common cause of cancer mortality in Western countries and claimed >50,000 lives a year only in the United States.4 Close to 70% of patients that are affected by colorectal carcinoma undergo surgical resection and 30% to 40% of them develop a recurrent disease (1). The liver is the most common site of metastatic CRC and complete resection of hepatic metastases is the only curative option; however, surgery can be done only in 20% of patients