Effects Of Lovastatin On Malignant Melanoma B16 Cells With Its Mechanism

Objective:To study the effects of lovastatin on prolif- eration of malignant melanoma cell B16 and its mechanisms. Meanwhile, observation of lovastatin joint anti-cancer drug cisplatin B16 cells in vivo and in vitro effects. Further clarify the role of possible mechanisms of lovastatin, to explore its treatment for malignant melanoma and the feasibility of chemical prevention.Methods:1 In vitro:B16 cells were cultured in vitro,effect of lovastatin on the proliferation of B16 cells was measured by MTT colorimetric method,and obaervated the morphological changes in B16 cells. MTT colorimetric method was performed to evaluate the potential cytostatic effect of combining lovastatin and cisplatin on malignant melanoma cell B16. To determine whether the combination of lovvastatin and cisplatin results in a synergistic cytostatic effect, Jin's formula was performed. In the analysis, there is synergy when the interaction index is more than 0.85; antagonism when the interaction index is less than 0.85.2 In vivo:The establishment of malignant melanoma in C57 mice subcutaneous xenografts model, were randomly divided into 5 groups. Gaps in the control group of eight: gived isotonic saline gavage once daily; The remaining 12 mice each group.Lov1 Group: lov gavage to 4mg/(kg.d); Lov2 Group: lov gavage to 16mg/(kg.d); Cisplatin Group: given cisplatin 10 mg/kg (d14, 21) by intraperitoneal injection; Joint group: given Lov 16mg/(kg.d) and cisplatin 10mg/kg (d14, 21)。After the tumors growed, measured the longest and shortest Path Drive of the mice tumors, Calculated the tumor size.By immunohisto- chemical determinated the expression of Survivin,Fas and VEGF.Results:1 In vitro: MTT assay showed that lovastatin (0.5,1,2,4,8, 16,32μmol/L) on B16 can inhibit cells proliferation. After cells dealed with different concentrations lovastatin of 24-72 hours,compared with the control group, the treatment group OD values have decreased to some extent, the difference was significant (P<0.01).With the increasing concentration of lovastatin, the extension of time, OD value has been gradually declining, that lovastatin on B16 cells was significantly inhibited the proliferation of the time - a dose-dependent effect. Lovastatin combined with cisplatin on B16 cells in vitro results showed that: 2,4,8,16μmol/L Lov can strengthen cisplatin on B16 cells in vitro. And with the increasing concentration of lovastatin, to cisplatin enhance synergies. Cells morphology was observed under light microscope showed that: cells shrinkage after treatment, the breakdown was irregular in shape, some cells appear at both ends of the pseudo-foot slender, exfoliated cells increased significantly inhibited the B16 cells growth, cells apparent Morphological changes. Jin's formula of interaction that different concentrations of cisplatin combined 2,4,6,8μmol/L of lovastatin q values greater than 0.85.2 in vivo: C57 mice inoculated B16 cells after 3-5 days, the majority of the tumor in mice can be touched, Tumor after 21 days, the treated mice tumor size was smaller than the blank group, the difference was significant(P<0.05). Three weeks after the mice were sacrificed, the Joint Group of Survivin in tumor tissue immunohistochemistry lowest score,Drug dealing with different concentrations can be reduced in tumor tissue Survivin expression; Blank group tumors with high expression of VEGF(5.750±0.619),joint Group tumor tissue showed low expression of VEGF(2.000±0.326);Blank group Fas expression in the tumor tissues low, the drug-treated group showed varying degrees of Fas expression, and the highest expression of the joint group. For each of the indicators, the treatment group compared with the blank IHS score, the difference was significant both(P<0.05).Conclusions :1 Lovastatin can inhibit the proliferation of B16 cells, the inhibition of B16 cell proliferation in a time - a dose-dependent relationship.2 Lovastatin can enhance cisplatin on B16 cells proliferation inhibition.3 Lovastatin can be reduced through the expression of Survivin, VEGF and play its inhibition of proliferation, invasion and metastasis.4 Lovastatin can increase the expression of Fas-induced apoptosis.5 Survivin expression and VEGF expression was positively correlated; The expression of VEGF and the expression of Fas was negatively correlated; Survivin expression and expression of Fas was negatively correlated.6 Lovastatin can be enhanced apoptosis induced by cisplatin in the role of speculation lovastatin increased B16 cells to chemotherapeutic drug sensitivity.