The Study Of Vitamin D Analogue EB1089on The Proliferation Of Hepatocellular Carcinoma Cells SMMC-7721

BackgroundPrimary liver cancer ranks as the fifth most frequent cancer globally and is thesecond most common cause of cancer death. In the worldwide, the most commonpathological type is hepatocellular carcinoma (HCC) which occurs from70%to85%of all cases among primary liver cancers approximately. Despite the extensive studyhaving been doing for many years, we has not been fully understood the etiology andmolecular biological mechanism, while efficient therapeutic options remain limitedand the prognosis is still far from optimistic. Therefore, develop more effectivescreening and treatment of this deadly disease is greatly meaningful for us to Effortsto elucidate the molecular biological mechanisms evolved in the progression of HCC.Many studies showed, vitamin D may be a protective factor of hepatocellularcancer, but the results were not consistent. Now the researchers think the protectivefunction of vitamin D may contain the following items: depress cellular proliferation,promote cellular differentiation and induce cellular adoptosis. Whereas the certainmechanism has not been clear yet. So detect the protective mechanism of vitamin Dcan help us clarify the relationship between vitamin D and hepatocellular cancer,which is very important for us to make prevent strategy and measurement forhepatocellular cancer.the long chain fatty acyl-CoA ligase(FACL) which belongs to the family of fatty acid metabolism enzymes is a key enzyme in controlling the free fatty acid andtypically activates fatty acid to acyl-CoA, an active form of fatty acid. Five isoformsof human FACL are identified as long-chain fatty-acid-CoA ligases1,3,4,5and6,based on their substrate specificity and tissue distribution. ADRM1is overexpressedin many types of human cancers has been proved by a growing body of evidence.Recent report shows that influenced FACL expression might be associatied with theinhibition of the proliferation of hepatocellular by vitamin D and its analogues.However, its tendeney to cause hypercalcaemia limited the clinical usefulness ofvitamin D is limited. EB1089is a more effective vitamin D analogue than vitamin Dto restrict cell growth and promote differentiation, but on the calcium metabolismexists much weaker effects. In this study, in order to explore the possible mechanismof vitamin D anologue EB1089in anti-tumor effect, we investigate the inhibitoryeffect of it on the proliferation of hepatocellular carcinoma cells in vitro and vivoculture and whether it influence the expression of FACL3, FACL4, FACL5.Method and Result1. SMMC-7721hepatocellular carcinoma cell lines were exposed to EB1089at1,10,100,1000nmol/L for24,48and72h, we surveyed the impact thatEB1089contributed SMMC-7721cell growth by MTT assay. As a result, theSMMC-7721cell proliferation is inhibited by EB1089significantly after24h,48h,72h along with the time and dosage increasing.2. After SMMC-7721was treated by EB1089for24h and48h, We detectedexpression of FACL3, FACL4, FACL5mRNA by RT-PCR. In result, therewere gradual decreased in expression of FACL4and FACL5mRNA andincreased in expression of ER mRNA, while there was no significant changein the expression of FACL3mRNA after EB1089treated SMMC-7721cellfor24h and48h along with effective time of EB1089increasing. 3. After SMMC-7721was treated by EB1089for24h and48h, We detectedexpression of FACL4and FACL5protein by Western-blot. In result, therewere gradual decreased in expression of FACL4and FACL5protein levelsand increased in expression of ER protein level after EB1089treatedSMMC-7721cell for24h and48h along with effective time of EB1089increasing.4. For in vivo analysis, SMMC-7721hepatocellular carcinoma cells werexenografted into BALB/c NU/Nu nude mice, mice were randomly assignedto a control group(n=10) or one of the treatment groups(2groups of10mice)receiving0.5or1μg/(kg·d) of EB1089. Control animals received equalvolume vehicle(ethanol). Tumor size was measured every five day withoutkilled and the tumor growth curve was made. Result displayed that profoundinhibition of tumor growth was observed at both of the treatment groupsalong with effective dosage of EB1089increasing.ConclusionThis suggests EB1089can significantly inhibit proliferation along with effectivetime and dosage of EB1089increasing in SMMC-7721due to EB1089downgrad-uating FACL4and FACL5expression and upgraduating ER expression.