A: AD-EGFP group B: ZD55-Sur-EGFP group C: ZD55-EGFP group D: AD-Sur-EGFP group E: PBS group (a) Representative tumor formations, 60 days after injection. (b) Tumor volume after 60 days of injection was quantitatively represented. Data were expressed as mean ± SD. *P < 0.01 vs other groups (c) Western

blotting of proteins from xenograft tumors. The result was consistent with that on cell level. Western blot analysis of Survivin in xenograft tumors To determine the effect of ZD55-Sur-EGFP MS-275 concentration on Survivin selleck inhibitor expression in vivo, we analyzed the Survivin protein in by western blot. As shown in Fig 9c, Survivin showed a marked reduction in ZD55-Sur-EGFP and AD-Sur-EGFP treated groups when compared with the PBS, AD-EGFP and ZD55-EGFP group. Furthermore, it is clearly that ZD55-Sur-EGFP suppressed Survivin expression more potent than AD-Sur-EGFP, and ZD55-EGFP, AD-EGFP and PBS had nearly no effect on Survivin expression. Discussion Colorectal carcinoma is the most frequent alimentary system malignancy, which accounts for 40% of the estimated new cancer

cases of the digestive tract [12]. Although the incidence of CRC in developed countries is slowly decreasing, it is increasing rapidly in developing countries. Treatments such as surgical operation, adjuvant chemotherapy and neo adjuvant chemotherapy have achieved great progress [13], but the reported survival rate of CRC within five years is not yet encouraging. The mortality of CRC is mainly PRN1371 purchase due to metastasis to distant

organs, especially to liver, which accounts for one-third of the metastatic colorectal cancers [14–18]. GNA12 It is urgent to establish a more effective therapeutics for CRC. RNA interference (RNAi) is a posttranscriptional gene silencing strategy first discovered in the nematode Caenorhabditis elegans [19]. Because of its high specifity and efficiency in down regulating gene expression, it has now become an excellent tool for exploring gene function. Many groups have worked on cancer gene silencing using RNAi in cell lines derived from different tissues, which lead to significant inhibition in cancer cell growth [20–24]. Also there are some in vivo studies using RNA interference strategies which achieve similar results [7, 25]. But the transfection efficiencies of traditional RNAi strategies are relatively low. In order to facilitate the application of RNAi in cancer gene therapies, improved methods for efficient introduction of small interfering RNA (siRNA) into target cells are needed. Oncolytic adenovirus as an anticancer agent is a potent treatment in various malignancies [26]. The best known oncolytic adenovirus named ONYX-015 is an E1B-55 kDa deficiency virus, which has shown promising results in head-and-neck cancer treatment combining with chemotherapy [27, 28]. Another oncolytic adenovirus, H101, similar to ONYX-015, was recently approved by the Chinese government to be used in combination with radiotherapy for head-and-neck cancers too [29].