The Effects Of Stichopus Japonicus Acidic Mucopolysaccharide On Proliferation And Differentiation Of Hela Cells And Its Mechanisms

Objective: To investigate the effects of Stichopus japonicus acidic mucopolysaccharide (SJAMP) on proliferation and differentiation of Hela cells and its mechanisms.Methods: Hela cells were cultured in vitro and treated with various concentrations of SJAMP. Its effects on the cells were evaluated by detecting follow indexes:(1) The effect of SJAMP on cells proliferation was evaluated by MTT assay;(2) The morphological change of Hela cells was observed by light microscope and the ultrastructural change of Hela cells was observed by electron microscope;(3) cyclinDl,CDK4,C-myc mRNA expressions in cells were determined by reverse transcription polymerase chain reaction(RT-PCR).Results: (1) MTT assay showed: the OD Value of each SJAMP group was lower than that of control group(P<0.01 except that P<0.05 between 0.5mg/ml group and control group). The OD Value decreased obviously with SJAMP concentration rising(P<0.01). The results showed that SJAMP had an inhibition effect on the proliferation of Hela cells and the growth inhibition effect was significant dose-dependent;(2) Light microscope showed that SJAMP-treated cells were fewer,smaller and thinner than control group and had long fusiform shape or round shape. The results showed that SJAMP could obviously inhibit the proliferation of Hela cells. The inhibition effect was stronger with concentration rising and action-time lasting. Electron microscope showed that under SJAMP function cell's karyoplasmic ratio decreased ; nucleus was smaller and its shape trended to rule shape and the nucleolus reduced or vanished, the heterochromatin increased, well-differentiated organelle appeared in the cytoplasm. The morphological change showed that SJAMP could induce Hela cells differentiate to mature cells;(3) RT-PCR reaction showed that compared with control group, SJAMP obviously decreased the expression of cyclinD1, CDK4 and C-myc genes and the effect was manifest with concentration rising and action-time lasting. Conclusion: SJAMP had an inhibition effect on proliferation and an induction effect on differentiation of Hela cells .The mechanisms of the effects might be related to many links, such as inhibiting the expression of cyclinD1 and CDK4. SJAMP could induce the differentiation of Hela cells by inhibiting the expression of C-myc gene.