Objective: To explore the effect of Xiao Chaihutang (XCHT) and its cold and hot herb-subtracted formulae on HCT116 human colon carcinoma cell proliferation

lipid accumulation and alkaline phosphatase

and investigate its mechanism. Method: HCT116 cells were cultured with XCHT

XCHT-Bupleuri Radix

XCHT-Scutellariae Radix

XCHT-Pinelliae Rhizoma

and XCHT-Zingiberis Rhizoma Recens at final drug concentrations of 0.5

1.0

1.5 g·L-1

and in addition

another blank control group and colchicine positive control groups (1.0

2.5

10.0 μmol·L-1) were set in this study. The proliferation viability of HCT116 cells was detected by 3-(4

5-dimethylthiazol-2-yl) -2

5-diphenyltetrazolium bromide (MTT) assay; the lipid accumulation was detected by Sudan red Ⅳ staining;alkaline phosphatase kit was used to detect the enzyme activity; heat stable test was used to distinguish tissue specific alkaline phosphatase and tissue non-specific alkaline phosphatase (TNAP)

and intestinal alkaline phosphatase specific inhibitor (L-phenylalanine) inhibition test was used to distinguish intestinal alkaline phosphatase (IAP) in tissue specific alkaline phosphatase. Result: As compared with blank control group

XCHT and its cold and hot herb-subtracted formulae all had obvious inhibitory effect on the cell proliferation activity of HCT116 human colon carcinoma cells and the inhibitory effect of XCHT was more obvious. The inhibitory effect was most obvious in colchicine positive control groups. The cell percentage of lipid accumulation in blank control group was significantly higher than that in XCHT and its cold and hot herb-subtracted formulae groups (P<0.01)

and the cell percentage of lipid accumulation was lowest in XCHT group (P<0.05). The cell percentage of lipid accumulation in XCHT-Bupleuri Radix group was significantly lower than that in XCHT-Pinelliae Rhizoma group and XCHT-Zingiberis Rhizoma Recens group (P<0.01). The cell percentage of lipid accumulation in XCHT-Scutellariae Radix was significantly lower than that in XCHT-Pinelliae Rhizoma group and XCHT-Zingiberis Rhizoma Recens group (P<0.01)

and there was no lipid accumulation in the colchicine positive control groups.The IAP activity was higher than TNAP activity in all the five XCHT and its cold and hot herb-subtracted formulae groups (P<0.01)

and the TNAP activity was higher than IAP activity in culture medium (P<0.01). The IAP activity in cells of XCHT-Bupleuri Radix group was higher than that in XCHT-Pinelliae Rhizoma group and XCHT-Zingiberis Rhizoma Recens group

and the IAP activity in XCHT-Scutellariae Radix group was higher than that in XCHT-Pinelliae Rhizoma group and XCHT-Zingiberis Rhizoma Recens group (P<0.01). In the culture medium

the TNAP activity in XCHT-Pinelliae Rhizoma group and XCHT-Zingiberis Rhizoma Recens group was higher than that in XCHT-Bupleuri Radix group (P<0.05) and XCHT-Scutellariae Radix. Conclusion: XCHT and its cold and hot herb-subtracted formulae can effectively inhibit HCT116 human colon carcinoma cell proliferation and XCHT (a combination use of cold and hot herbs) exhibited the strongest inhibitory effect. There was a significant difference between the effect of cold herb-subtracted formulae and hot herb-subtracted formulae on lipid accumulation and alkaline phosphatase. A combination use of cold and hot herbs in XCHT

could act on TNAP and IAP respectively

and regulate fat transport and metabolism

thus inhibiting the growth of cancer cells.