The Partial CDNA Clone Of Novel Genes Differentially Expressed In Vincristine Resistant Human Gastric Cancer SGC-7901 Cell

The resistance of neoplastic cells to chemotherapeutic agents is a significant problem in the clinical management of malignant tumors. A variety of molecular mechanisms of multidrug resistance (MDR) have been identified in human drug-resistant cell lines, P-glycoprotein (P-gp)-mediated drug efflux is the most well-characterized cellular mechanism of MDR: several other non-P-gp membrane transporter proteins have also been implicated in the development of an MDR phenotype in malignancies These include the MDR-related protein (MRP), the lung-resistance protein (LRP), and the transporter of antigenic peptides (TAP) Since some multidrug-resistant (MDR) tumor cell lines show MDR but do not over-express Pgp, MRP or LRP,the molecular mechanisms for sensitivity or resistance of tumor cells towards chemotherapy are only partially understood, MDR involves some other undetermined mechanisms. Our work is an attempt to identify the differentially expressed genes for drug resistance that is especially unrelated to MDR1 or MRP or LRP gene, Methodology striving to identify differentially expressed messages is critical to the process of indentifying the genes responsible for the MDRWe initially employed the method of mRNA differential display technique to identify differentially expressed messages in human gastric cancer SGC-7901cell and its vincristine resistant cell line. Six differentially displayed bands(VRF1. VRF2, VRF3. VRF4. VRF5. VRF6) were obtained from SGC-7901/VCR on PAGE, they were re-amplified and cloned into pUC19 vector or pGEM-7Zf(+)T-A vector, RNA dot blot of the six cDNA fragments show that VRF1. VRF2, VRF3 and VRF4 were especially expressed in human gastric cancer SGC-7901 vincristine resistant cell , sequence homology analysis results show that the four cDNA fragments have no homologous sequences in GenBank, indicting that they were the partial cDNA sequences of new genes, VRF1,...