The Effect Of All-trans Retinoic Acid And Oxaliplatin In Human Liver Cancer SMMC-7721Cells

Background and purposePrimary liver cancer is one of the top10common cancers in the world. It is the leading high gastrointestinal malignant tumor, of which about90%is hepatocellular carcinoma. chemotherapy is the main treatments for the patients with advanced liver cancer. Though the imerging of new chemotherapy for liver cancer are found recently and the short-term efficacy is encouraging, but the long-term survival in patients with liver cancer doesn’t get significantly improvement. There is no evidence that it could be significantly prolongs patient’s survival for present chemotherapies. Among them, the drug-resistance and the severe side effects of the drug restricted their clinical application. Therefore, new drug and new combined therapies for liver cancer treatment are still hot points for researchers and clinicians.ATRA is the main metabolite of vitamin A, which is known as a differentiation inducing agent. The information at home and abroad shows that it could induce differentiation and improve the sensitivity in solid tumors. L-OHP is the third generation of platinum anticancer compounds, and like the other platinum drugs. Tts function is to form chains, intra-/inter-DNAs in tumor cells, which interrupts DNA synthesis and finally produces cell poison effect and antitumor activity. Now many experiments have proofed that L-OHP could inhibit liver cancer cell proliferation and induce apoptosis, L-OHP has been permitted to clinical treatment, but its usage still need to be optimized for efficacy.No report on combined therapy of ATRA and L-OHP on patients with liver cancer. The apoptosis effect in SMMC-7721cells was observed in vitro induced by ATRA or/and various concentrations of L-OHP.Materials and methods1. The SMMC-7721cells was treated with ATRA, various concentration of L-OHP, respectively or in combination. Cell morphological changes were observed in SMMC-7721cells under the inverted microscope.2. MTT method was applied to detect cell proliferation after treatment by ATRA, various concentration of L-OHP, or in combination in SMMC-7721cells within24h,48h,72h.3. Flow cytometry was used to detect the changes of apoptosis rates and cell cycles of SMMC-7721cells after treated with ATRA and20mg/L L-OHP for48h.ResultsIt could be seen from the inverted microscope that the growth of the cancer cells was in good conditions. Cell body was bright and cell shape was irregular spindle and long. Cell gaps widened, part of the cells broken into fragments, and the cells showed apoptotic changes after treated with ATRA for48h; It was observed most cells floating in the culture fluid,48h after combined use of ATRA plus L-OHP and apoptosis of cells was increased obviously; The MTT method showed that ATRA could inhibit the proliferation of SMMC-7721cells and the inhibition effect was most obvious at48h; Different concentrations of L-OHP monotherapy could significantly inhibit SMMC-7721cell growth, dose-and time-dependently anti-humor; And the effect to the cells increased apparently when using two drug combination compared with any stingle agents for cell growth inhibition effect (P<0.05).It was observed between ATRA combined with40mg/LL-OHP and ATRA combined with20mg/LL-OHP at48h and72h. the inhibition rate between them is no statistically significant difference (P>0.05). Results from the flow cytometry showed that most of the SMMC-7721cells blocked in G0/G1phase after ATRA treatment, and in S phase after L-OHP treatment. S phase blockage was enhanced obviously and cell apoptosis significantly increased when treated with combination of ATRA and L-OHP (P<0.01).Conclusions1. The growth of the SMMC-7721liver cancer cells could be inhibited by ATRA, especially at48h.2. The growth of the SMMC-7721liver cancer cells could be significantly inhibited by10mg/L,20mg/L and40mg/L concentrations of L-OHP in dose/time dependent pattern.3. The anti-tumor effect was enhanced when ATRA combined with L-OHP was used in SMMC-7721cells. ATRA could reduce the amount of L-OHP, which has a synergistic effect.4. G0/G1phase block could be induced by ATRA in SMMC-7721cells, and S phase block by L-OHP; S phase block was enhanced by combination of ATRA and L-OHP in SMMC-7721cells, and the cell apoptosis ratio could be increased significantly.