While

no significant difference in the expression of anti-actin was found among them, caspase-9 was found to be expressed to a higher extent in Lip-mS + CDDP treatment groups as compared to NS, CDDP alone, Lip-mS alone treatment groups. Figure 4 Combination of Lip-mS and CDDP enhanced the www.selleckchem.com/products/U0126.html induction of apoptosis in vivo. Tissue sections from tumor-bearing mice treated with NS (a), CDDP (b), Lip-mS (c), or Lip-mS Tariquidar + CDDP (d) were stained with FITC-DUTP. Percent apoptosis was determined by counting the number of apoptotic cells and dividing by the total number of cells in the field (5 high power fields/slide). (A) Representative Field from each group. (B) Percent apoptosis in each group. Values were expressed as means ± SE. An apparent increase in the number of apoptotic cells was observed within tumors treated with a combination of Lip-mS and CDDP compared with the other treatments (P < 0.05). Figure 5 Inhibition of intra-tumoral angiogenesis assayed by CD31 staining of microvessels. Vascularization within tumors was detected by an antibody to CD31; representative images were taken under a light microscope (×400) in randomly-selected fields. Tumors of the NS (a) and CDDP (b) treatment groups demonstrated high microvessel density,

while those of the Lip-mS (c) and Lip-mS + CDDP (d) treatment groups showed apparent inhibition of angiogenesis. Discussion Survivin has received much greater attention in recent years, thanks not only AZD8931 to its anti-apoptotic effects, but also its relation to chemoresistance. It was reported that survivin acts constitutively in a panel of tumor cells, and approaches designed to inhibit survivin expression or function may lead to tumor sensitization to chemical and physical agents [13]. Hence, the combination of genetic and chemotherapeutic approaches has been a topic of great interest. CDDP is widely used for the treatment of a variety of human PTK6 tumors such as lung cancer[14]. CDDP is a well-known DNA damaging agent, and it is currently thought that DNA platination is an essential first

step in its cytotoxic activity[15]. However, continuous infusion or multiple administration of CDDP is an excellent regimen for cancer patients because of its adverse effects [16, 17]. Therefore, approaches to improve the sensitivity to drug doses are a subject of intensive study in cancer care. Treatments combining genetic and chemotherapeutic approaches are a relatively new instrument in the fight against cancer. Our study combining a Lip-mS genetic approach with CDDP significantly increased the anti-tumor effects of single chemotherapy. Moreover, the interactive anti-tumor effect of the combined treatment was greater than the expected additive effect. These data suggest that inhibition of survivin using a dominant-negative mutant, survivin T34A, can sensitize LLC cells to CDDP. Reduction of apoptosis plays a very important role in tumor initiation, progression, and drug resistance.