title: [MDR-reversing effect of short peptide binding specifically to multidrug-resistant gastric cancer cells].
abstract: OBJECTIVE
  To investigate the binding effect of the short peptide SY1 to the multidrug-resistant gastric cancer cell line SGC7901/VCR cells and its reversing effect on those cancer cells.
  
  
  METHODS
  The cultured cells were divided into two groups named SGC7901 and SGC7901/VCR. The SGC7901/VCR group was co-cultured with vincristine (VCR). SY1 was obtained from cyclic 7-mer peptide library by differential screening. Immunofluorescence technique was used to detect the capacity of SY1-containing positive phage specifically binding to SGC7901/VCR cells, compared with that of the negative phage and unrelated phage. MTT assay in vitro was performed to analyze the alteration of drug resistance of SGC7901/ VCR cells, using the positive phages and the chemically synthesized SY1 peptide. Flow cytometry assay was performed to detect the accumulation and retention of adriamycin (ADM) in the SGC7901/VCR cells.
  
  
  RESULTS
  Immunofluorescence analysis showed that the SY1-containing positive phages could bind to the SGC7901/VCR cell surface but not to its parent cell line SGC7901 cells. The unrelated phage and negative phage did not bind to SGC7901/VCR cells. These results indicated that SY1 could specifically bind to SGC7901/VCR cells. MTT assay in vitro showed that the survival rate of SGC7901/VCR cells was reduced considerably by the positive phages and the chemically synthesized SY1 peptide (P <0. 05), indicating that SY1 enhanced the sensitivity of SGC7901/VCR cells to chemotherapeutic drug VCR. Flow-cytometric detection showed that SY1 enhanced the accumulation of ADM in the SGC7901/VCR cells, compared with that of the negative phages and the unrelated phages (P <0.05).
  
  
  CONCLUSIONS
  SY1 not only is able to bind to SGC7901/VCR cells specifically, but also can partly reverse the resistance of SGC7901/VCR cell line to chemotherapeutic drug VCR. Those findings might be important to open a new approach to reverse the gastric cancer MDR.
authors.affiliation: State Key Laboratory of Biology and PLA Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Ding
authors.forename: Tao
authors.initials: T
authors.lastname: Lin
authors.forename: Shuang
authors.initials: S
authors.lastname: Han
authors.forename: Shan-shan
authors.initials: SS
authors.lastname: Cao
authors.forename: Fu-lin
authors.initials: FL
authors.lastname: Ge
authors.forename: Guang-qun
authors.initials: GQ
authors.lastname: An
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.forename: Ting
authors.initials: T
authors.lastname: Lei
authors.forename: Fei-hu
authors.initials: FH
authors.lastname: Bai
authors.forename: Dai-ming
authors.initials: DM
authors.lastname: Fan
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D001435:Bacteriophages / Q000235:genetics; D001665:Binding Sites; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D019151:Peptide Library; D010456:Peptides, Cyclic / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014750:Vincristine / Q000494:pharmacology
chemical_list: D000903:Antibiotics, Antineoplastic; D000972:Antineoplastic Agents, Phytogenic; D019151:Peptide Library; D010456:Peptides, Cyclic; D014750:Vincristine; D004317:Doxorubicin