Construction and identification of recombinant vectors carrying herpes simplex virus thymidine kinase and cytokine genes expressed in gastric carcinoma cell line SGC7901

Abstract

AIM:To construct and identify the recombinant vectors carrying herpes simplex virus thymidine kinase (HSV-TK) and tumor necrosis factor alpha (TNF-α) or interleukin-2 (IL-2) genes expressed in gastric carcinoma cell line SGC7901. METHODS:The fragments of HSV-TK, internal ribosome entry sites (IRES) and TNF-α or IL-2 genes were inserted in a TK-IRES-TNF-α or TK-IRES-IL-2 order into pEGFP-N 3 and pLXSN to generate the therapeutic vectors pEGFP-TT, pEGFP-TI, pL(TT)SN and pL(TI)SN respectively, which were structurally confirmed by the digestion analysis of restriction endonuclease. The former two plasmids were used for the transient expression of recombinant proteins in the target cells while pL(TT)SN and pL(TI)SN were transfected into SGC7901 cells by lipofectamine for the stable expression of objective genes through G418 selection. The protein products expressed transiently and stably in SGC7901 cells by the constructed vectors were confirmed by fluorescent microscopy and Western blot respectively. RESULTS:The inserted fragments in all constructed plasmids were structurally confirmed to be consistent with that of the published data. In the transient expression, both pEGFP-TT and pEGFP-TI were shown expressed in nearly 50% of the transfected SGC7901 cells. Similarly, the G418 selected vectors PL(TT)SN and PL(TI)SN were confirmed to be successful in the stable expression of the objective proteins in the target cells. CONCLUSION:The constructed recombinant vectors in the present study that can express the suicide gene TK in combination with cytokines genes may serve as the potential tools to perform more effective investigations in future for the gene therapy of gastric carcinoma.Zhang JH, Wan MX, Yuan JY, Pan BR. Construction and identification of recombinant vectors carrying herpes simplex virus thymidine kinase and cytokine genes expressed in gastric carcinoma cell line SGC7901.

Inhibitory effect of Dendrobium officinale polysaccharide on human gastric cancer cell xenografts in nude mice

“…This indicates that, DDPA may inhibit the growth of SGC-7901 tumor in nude mice by up-regulating the serum TNF-α and IL-2 levels. This is the same with the previous studies (Zhang et al, 2004;Tang et al, 2013).…”

Do there exist synergistic antitumor effects by coexpression of herpes simplex virus thymidine kinase with cytokine genes on human gastric cancer cell line SGC7901?

“…The mouse fibroblast cell line NIH3T3 and the amphotropic retroviral packaging cells PA317 were the generous gifts from The recombinant vectors pL(TT)SN and pL(TI)SN, which express TK-IRES-TNF-α and TK-IRES-IL-2 genes respectively, as well as the control plasmid pL(TK)SN carrying only TK fragment were constructed and identified in our previous study [15] . The empty plasmid PLXSN used as another control vector was provided by Dr. Yu Bing (Fourth Military Medical University, Xi'an, China).…”

“…Gene therapy with HSV-TK and cytokine genes together may produce a complementary effect, and has become a new insight for the treatment of malignancies [13,14] . Previously, we constructed two retroviral vectors, pL(TT) SN and pL(TI)SN, which have been confirmed to express TK-IRES-TNF-α and TK-IRES-IL-2 genes respectively in the gastric cancer cell line SGC7901 [15] . In the present study, the synergistic antitumor effects of these vectors on human gastric cancer cells were investigated in the presence of GCV to confirm their efficiency.…”

The Roles of Macrophages and Nitric Oxide in Interleukin-3-Enhanced HSV-Sr39tk-Mediated Prodrug Therapy

“…However, its efficacy is still lacking and is generally insufficient to eradicate malignant tumors completely. A number of therapeutic approaches have been proposed to enhance the anti-tumor effect of suicide gene therapy by inducing an immune response to tumor cells via co-expression of cytokine genes, such as IL-2 [23], IL-2 and TNF-α [24], IL-12 [13], and IL-21 [25]. In this study, we demonstrate that bicistronic expression of IL-3 and HSV-sr39tk/GCV suicide gene system exerts a synergistic effect inhibiting the growth of TRAMP-C1 prostate cancer cells in vivo , but not in vitro .…”