Effects of leptin on proliferation and apoptosis of colorectal carcinoma SW480 cells

Abstract

Objective To observe the effects of leptin on proliferation and apoptosis of colorectal carcinoma SW480 cells, and to explore its possible mechanism. Methods After stimulation with various doses of leptin (0, 20, 50, 100, 200 ng/ml) for different durations (12, 24, 36 and 48 h), the cell proliferation rate was determined by cell counting kit-8 (CCK-8) assay. Serum deprivation was used to induce apoptosis of SW480 cells stimulated with leptin. Cell apoptosis was assessed by double staining with Annexin V and flow cytometry. The mRNA expression of Survivin and beta-catenin in SW480 cells was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Results As compared with the control group, with the increase of leptin concentration (20, 50, 100 and 200 ng/ml), the proliferation rate of colorectal cancer SW480 cells [12 h: (118.1±2.0)%, (132.6±3.9)%, (141.9±1.3)% and (145.6±4.9)%, P=0.000, 0.000, 0.000, 0.000; 24 h: (120.8±2.7)%, (137.0±1.0)%, (149.7±1.6)% and (176.6±2.9)%, P=0.000, 0.000, 0.000, 0.000; 36 h: (123.9±0.5)%, (133.9±0.8)%, (169.4±1.1)% and (182.8±1.1)%, P=0.001, 0.001, 0.000, 0.000; 48 h: (132.7±1.2)%, (146.0±3.3)%, (172.0±0.6)% and (185.5±0.5)%, P=0.001, 0.005, 0.000, 0.000] was increased (P<0.05), and the serum starvation-induced apoptosis rate [(30.23±0.15)%, (28.87±1.01)%, (18.23±0.35)%, (16.33±0.51)% and (9.20±0.26)%] was decreased (P=0.388, 0.000, 0.001, 0.000). The mRNA expression levels of Survivin and beta-catenin were increased (P=0.007, 0.003, 0.000, 0.000; P=0.000, 0.000, 0.000, 0.000). Conclusion Leptin could promote the proliferation and inhibit the apoptosis of SW480 cells. Key words: Leptin; Colorectal carcinoma; Proliferation; Apoptosis