ABSTRACT
Aim: To screen BRAFV600E CT26 cell inhibitors from monomers of traditional Chinese medicine (TCM). Methods CT26 cell line was constructed with lentivirus plasmid to stably express BRAFV6C0E. The proliferation, migration and expression of related proteins in MEK/ERK signaling pathway were detected. The monomers of TCM were detected for biological activities as potential BRAF inhibitors by Discovery Studio 4. 0, and further evaluated by MTT assay. Results: The proliferation and migration of BRAFV6C0E CT26 cells were obviously strengthened compared with wild type control. The expressions of proteins in MEK/ ERK pathway were also activated in BRAFV6C0E CT26 cells. Compared with wild type control, Aloin, Angoroside C and Cyasterone exhibited the potent effect against BRAFV600E in CT26 cells (P <0. 05), and could down-regulate the expression of BRAFV600E. Conclusion: Aloin, Angoroside C, Cyasterone might be the potent inhibitors against BRAF for colon treatment.
ABSTRACT
Colorectal cancer (CRC) is one of the most prevalent forms of cancer that shows a high mortality and increasing incidence. There are numerous successful treatment options for CRC, including surgery, chemotherapy, radiotherapy and immunotherapy; however, their side effects and limitations are considerable. Probiotics may be an effective strategy for preventing and inhibiting tumour growth through stimulation of host innate and adaptive immunity. We investigated and compared potential anti-tumour immune responses induced by two isolated Lactobacillus strains, Lactobacillus plantarum A and Lactobacillus rhamnosus b, by pre-inoculating mice with lactobacilli for 14 days. Subsequently, subcutaneous and orthotopic intestinal tumours were generated in the pre-inoculated mice using CT26 murine adenocarcinoma cells and were assessed for response against the tumour. Our results indicated that oral administration with L. plantarum inhibited CT26 cell growth in BALB/c mice and prolonged the survival time of tumour-bearing mice compared with mice administered L. rhamnosus. L. plantarum produced protective immunity against the challenge with CT26 cells by increasing the effector functions of CD8+ and natural killer (NK) cell infiltration into tumour tissue, up-regulation of IFN-γ (but not IL-4 or IL-17) production, and promotion of Th1-type CD4+ T differentiation. Consequently, our results suggest that L. plantarum can enhance the anti-tumour immune response and delay tumour formation.
ABSTRACT
To investigate the induction of apoptosis of mouse colonic adenocarcinoma CT26 cells by recombinant Clostridium difficile toxin B (rTcdB), CT26 cells were exposed to different concentrations of rTcd B. Inhibition of cell proliferation was measured by MTT assay. The activation of Caspase 3 was measured by colorimetric method. Cell morphological analysis and flow cytometry were performed to confirm cell apoptosis. rTcd B inhibited the proliferation of CT26 cells in a timeand dose-dependent manner. Caspase 3 activity in CT26 cells was elevated remarkably after rTcd B exposure for 6 h, 12 h, 18 h or 24 h, as compared with the control group. Morphological changes were observed by fluorescence microscopy. The exposure of rTcd B to CT26 cells induced a timeand dose-dependent apoptotic cell death as determined by flow cytometry analysis. The results showed that recombinant Clostridium difficile toxin B induced apoptosis of CT26 cells.