Objective:To investigate the inhibitory effect and the related mechanism of Yiqi Jianpi Fang on aberrant crypt focus (ACF) in Wister rat colorectal cancer model.Methods:50 Wistar rats were randomly divided into 5 groups:TCM low dose group(TCM solution diluted 3 times,5 mL/kg daily gastric volume),TCM middle dose group (5 mL/kg daily gastric volume),TCM high dose group (15 mL/kg daily gastric volume),model group,normal group.With 10 rats in each group.The colorectal tissues were observed under microscope after methylene blue staining by immunohistochemistry method.Results:Compared with the model group,the number of ACF and large ACF in each TCM group were decreased (P＜0.05),and the number of ACF in the TCM middle dose group reduced most obvious,and the difference was statistically significant (P＜0.05).The proliferation indexs of PCNA in intestinal gland cells 24 h and 48 h after modeling in the TCM groups were higher than those in the model group,and the difference was statistically significant(P＜0.05).The apoptosis index of intestinal gland cells 24 h and 48 h after modeling in the TCM groups were higher than those in the model group,and the difference was statistically significant(P＜0.05).The ectopic expression of β-catenin in TCM groups were lower than that in the model group,and it was highest in the high dose group,than was the low dose group,and the middle group was lowest(P＜0.05).The expression of MMP-7 in TCM groups were lower than that in the model group,and it was highest in the low dose group,than was the high dose group,and the middle dose group was lowest (P＜0.05).Conclusion:Yiqi Jianpi Fang can significantly reduce the number of ACF in Wister rats,inhibit the activation of Wnt signaling in colorectal cancer,reduce the incidence of colorectal cancer,and have a certain preventive effect.

Objective:To isolate cell spheres containing cancer stem cells (CSCs) from lung cancer cell lines (A549 and H1299) and iden-tify their biological characteristics. Methods:By adopting the method of serum-free suspension culture, A549 cells and H1299 cells were cultured on no-adhesion plate to form tumor spheres. Clone assay, CCK-8 assay, and Transwell assay were employed to observe proliferation, self-renewal and invasion of tumor spheres. Besides, RT-PCR was performed to compare the expression levels of stem cell markers between sphere cells and adherent cells. Adherent A549 cells and A549 cell spheres were inoculated subcutaneously in nude mice and the tumor growth was assessed. Results:Isolated CSCs from A549 cells and H1299 cells in serum-free medium (SFM) without adhesion could grow as floating cell spheres. The results demonstrated that the self-renewal, proliferation and invasion of A549 and H1299 sphere cells were stronger than parent cells (P<0.05). When compared with adherent cells, the mRNA level of expres-sion of cell spheres' stem cell markers (Oct4 and Nanog) were significantly high (P<0.05) and A549 spheres had a stronger tumorigenici-ty in nude mice. Conclusion:SFM without adhesion can be a quick and easy method to construct stem cells model from human lung adenocarcinoma cell lines A549 and H1299.