OBJECTIVETo study the regulation of the mucin protein in colon cancer cell line HT-29 by recombinant human interleukin-6(rIL-6) and to further elucidate the development of colon cancer.

METHODSThe HT-29 cells were treated with different concentrations of rIL-6(1, 2, 5, 10 and 20 μg/L), then flow cytometry and RT-PCR were used to detect the expression of mucin1 and mucin2. Transwell invasion assay was used to observe the effect of invasion capability of rIL-6 to HT-29 cells.

RESULTSIn colon cancer, the expression of mucin 1 could be promoted by rIL-6 with concentration above 2 μg/L, the expression rates were(12.5±1.6)%, (26.6±2.7)%, (33.9±2.8)% and (58.9±2.5)%, respectively, higher than (8.0±0.8)% in the negative controls (P<0.01), meanwhile, the expression of mucin 2 decreased by rIL-6 with concentration above 2 μg/L, the expression rates were(30.5±2.6)%, (17.0±2.7)%, (11.0±2.0)% and (5.3±1.8)%, respectively, lower than (41.6±3.6)% in negative control(P<0.01). With the increase in rIL-6 concentration, the invasion of HT-29 cells was enhanced.

CONCLUSIONSIn colon cancer, the expression of mucin1 can be promoted by rIL-6, while the expression of mucin2 can be inhibited. IL-6 is a promoting effect factor in colon cancer invasion and metastasis.