OBJECTIVETo investigate the effect of growth suppression and gap junctional intercellular communication (GJIC) on osteosarcoma cell line OS732 transduced with the exogenous N-terminal truncated retinoblastoma (Rb) gene.

METHODSRecombinant eukaryotic expression plasmid harbouring 1.65 kb Rb gene was constructed and transduced into OS732 cells. Rb mRNA expression was detected by RT-PCR and Northern blot. The cell count, cell cycle analysis and soft agar colony formation test were used to observe growth features. RT-PCR and Lucifer yellow dye transfer were carried out to measure GJIC.

RESULTSBoth exogenous and endogenous Rb gene could be detected in OS732 cell transduced with the N-terminal truncated Rb gene. Compared with the parental cells, change in morphology of Rb-transduced cells were found; growth rate decreased; amount of colony formation reduced; cell cycle arrested at G(0)/G(1) checkpoint; Connexin43 expression and GJIC enhanced.

CONCLUSIONSThe malignant phenotype of OS732 is inhibited and GJIC is increased by transduction of N-terminal truncated Rb gene.