Experimental research Therapeutic anti-tumor effect of exogenous apoptin driven by human survivin gene promoter in a lentiviral construct

Abstract

IntroductionThe aim of this study was to construct a lentivirus vector with survivin promoter (pSur)-driven apoptin and test its efficiency in suppressing the growth of tumor cells.Material and methodsExpression cassettes with different fragments of survivin gene promoter (pSur, 161 bp, 272 bp, 990 bp) driving 6XHis-tagged apoptin were constructed to generate recombinant lentivirus, of which the inhibitory effect on tumor cells was compared. The activity of different pSur in 293FT, and 272 bp pSur in primary bone marrow mesenchymal stem cells (BMSCs), SW480, Hela and MCF-7 was examined by Western blot. Their ability to induce apoptosis in SW480 cells was determined by annexin-V staining. The inhibitory effect of letivirus containing different pSur-driven apoptin on nude mice-xenografted SW480 cells was assessed by tumor size and pathological observation.ResultsThe 272 bp and 990 bp pSur displayed comparable effects in terms of promoter activity, cell apoptosis/necrosis and G1 phase arrest in vitro, and growth of xenograft tumor in vivo. When lentivirus containing 272 bp pSur was tested, it drove high apoptin expression in tumor cells (SW480, Hela and MCF-7) and weak expression in primary bone marrow mesenchymal stem cells. Xenograft to nude mice using infected Sw480 cells showed that lentiviruses possessing 272 bp and 990 bp pSur were able to significantly induce tumor cell death, focal necrosis, and tumor growth lag.ConclusionsThe data indicated that pSur-apoptin expression cassette in lentivirus vector ensures specific suppression of tumor cells, and may be applicable to monitor malignant transformation of transplanted cells.

Antitumor effects of a dual cancer-specific oncolytic adenovirus on colorectal cancer in vitro and in vivo

“…An MTT assay was used to measure the viability of the cells infected with the various adenoviruses ( 17 ). As shown in Fig.…”

“…In cancer gene therapy, the specificity of the promoter that controls the expression of an exogenous gene to target cells determines the treatment validity ( 17 ). Telomeres are repeated DNA sequences that provide protection for chromosomes ( 18 ).…”

Cancer Treatment Goes Viral: Using Viral Proteins to Induce Tumour-Specific Cell Death

“…More recently a dual replicative AdV (Ad-Htert-E1A-Apoptin) expressing both Apoptin and E1A was to be extremely effective in treating lung metastasis in a mice model [173,174]. Lenti-viral mediated delivery has also been used for the delivery of CAV-Apoptin to both cellular models and mice models [175,176]. Moreover, Baculoviral delivery has been shown to work well for the delivery of Apoptin both in vitro and in vivo [177].…”

Viral genes as oncolytic agents for cancer therapy

“…However, prior immunity to adenovirus may hamper the effectiveness of the adenoviral-mediated transgene transfer; hence, other viral vectors have also been tested [188]. A lentiviral-based delivery vehicle carrying apoptin gene under human survivin promoter was able to suppress the growth of human colon cancer xenograft in nude mice [189]. In another study, lentiviral vector carrying (LV-SP-TAT-apoptin) a gene that codes for fusion protein (TATapoptin) with a secretory signal (SP) was constructed with the aim that its infection to cancer cells will result in the secretion of TAT-apoptin which would diffuse to nearby cells; thus, an enhanced tumor cell death will occur [190,191].…”