Berberine inhibits non-small cell lung cancer cell growth through repressing DNA repair and replication rather than through apoptosis.

At present, there are still many problems in the treatment of lung cancer, such as high cost, side effects and low quality of life. The advantages of traditional Chinese medicine (TCM) in the treatment of lung cancer are reflected. Berberine has been increasingly popular in colorectal cancer treatment, but little is known about its bioactivity against non-small cell lung cancer (NSCLC). Cell proliferation, cell apoptosis, cDNA microarray, gene and protein expression, and NSCLC transplanted tumour growth were performed. Berberine suppressed NSCLC cell proliferation and colony formation in vitro and inhibited NSCLC tumour growth in subcutaneously transplanted tumour lung tumour models, leading to prolonged survival of tumour-bearing mice. However, berberine did not induce the cleavage of Caspase 3 and PARP1, and could not induce apoptosis in all NSCLC cells. Moreover, 646 genes were differentially expressed upon berberine administration, which were involved in seven signal pathways, such as DNA replication. In cDNA microarray, berberine downregulated the expression of RRM1, RRM2, LIG1, POLE2 that involving DNA repair and replication. Our findings demonstrate that berberine inhibits NSCLC cells growth through repressing DNA repair and replication rather than through apoptosis. Berberine could be used as a promising therapeutic candidate for NSCLC patients.