Objective

To observe the effects of Tenglong Buzhong Decoction (TLBZD), a compound traditional Chinese herbal medicine, on proliferation and apoptosis of colon carcinoma cell line LS174T in vitro.
Methods

Human colon carcinoma cell line LS174T and human colon epithelial cell line CRL-1790 were treated with different doses of TLBZD. Cell proliferation was detected with cell counting kit-8 (CCK-8) assay and clone formation assay. Cell cycle and apoptosis were detected by flow cytometry, and caspase-3, -8 and -9 activities in LS174T cells were detected by colorimetric assay.
Results

TLBZD had no obvious cytotoxicity in normal CRL-1790 cells. After 72-hour treatment of 1 mg/mL TLBZD, or 48- and 72-hour of 2 mg/mL TLBZD, or 24-, 48- and 72-hour of 5-20 mg/mL TLBZD, proliferation of LS174T cells was significantly inhibited. Clone formation of LS174T cells was significantly inhibited by 1 to 20 mg/mL TLBZD treatment. TLBZD at doses of 5 to 20 mg/mL also induced apoptosis and cell cycle arrest at G0/G1 phase in LS174T cells. In addition, caspase-3, -8 and -9 activities were significantly elevated after 5 to 20 mg/mL TLBZD treatment.
Conclusion

TLBZD can inhibit cell proliferation, arrest cell cycle at G0/G1 phase, and induce apoptosis in LS174T cells, which may be related to activating of caspase-3, -8 and -9.

Key words: Colon neoplasm, Chinese medical formula, Cell proliferation, Apoptosis, Caspases, In vitro, LS174T cells