Preliminary Study On The Microrna Expression Profile And Molecular Mechanisms Of Paclitaxel-Induced Apoptosis In HEPG2and L02Cells In Vitro

Hepatoceilular cancer is the third common cause of cancer mortality in the world. So far. many attempts have been made to predict the biology of hepatocellular tumors to determine the prognosis and to develop new therapeutic strategies. With the advent of miRNA technology in recent years, it is now possible to expand our knowledge to better understand hepatocellular cancer by analyzing miRNA mediated pathways. Paclitaxel. a DNA-damaging agent, has been widely used to treat patients with human tumors including ovarian, breast, non-small cell lung tumors, and head and neck carcinomas in clinic. We postulated that microRNAs(miRNA) might be involved in HCC target-chemotherapy with paclitaxel. Analysis of paclitaxel chemotherapy miRNAs. could help us to better interpret the molecular mechanism of the drug affection and adverse reactions, and to provide the theory basis for searching new miRNAs markers and chemotherapy drugs combined miRNAs treatment strategy.Cell viability proliferation assays were conducted to test the sensitivity of the HepG2cells and L02cells to paclitaxel. The morphological changes of apoptosis were assessed with DAPI staining. The miRNA profile of HepG2cells treated or not with paclitaxel was separately evaluated in HN and HP. The miRNA profile of L02cells treated or not with paclitaxel was separately evaluated in LN and LP. Differential expression patterns of miRNA in the HP. HN. LP. LN cells were analyzed using novel LNA technology, differentially expressed miRNAs molecule were screened by the Bioinformatics to classify its expression pattern.Through the analysis get the following conclusion:(1) Paclitaxel on HepG2and L02cells have obvious inhibition:1C50was93.02nM/L24h, HepG2cells at24h after drug appeared obvious apoptosis characteristics of nuclear pyknosis burst.(2) HepG2cells and L02cells can be correctly distinguished by using miRNAs microarray:we found that34miRNAs have taken place in these two cell lines, including13upregulated genes and21downregulated genes, predicted target genes are more focused on cancer pathways and PI3K/Akt signaling pathway.(3) Paclitaxel drug treatment does affect the miRNA expression of HepG2cells:in this paper, a total of54different miRNAs was founded, including41upregulated genes and13downregulated genes, the TGF-β pathway is the greatest influenced pathway, the most genes involved in target pathway are PI3K/Akt pathway. Ingenuity Pathway Analysis (IPA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed for the miRNAs and their putative targets to identify the potential pathways and networks involved in paclitaxel apoptosis.(4) Paclitaxel affect the miRNA expression of L02cells, and the changed miRNAs are not in conformity with HepG2:in this paper, a total of116different miRNAs was founded, among them, including49upregulated genes and67downregulated genes, P53pathway is the greatest influenced pathway.(5) Our results found that, miR-1290, miR-508-5p and miR-509-5p have same change by paclitaxel-therapy in HepG2cells and L02cells, suggesting these3miRNAs could become biomarkers in paclitaxel.Our data clearly showed the differential expression miRNAs in HN, HP, LN, LP cells, which could potentially target many important pathways including PI3K/Akt, MAPK, TGF-β signaling, ErbB signaling, P53signaling, cell cycle, mTOR signaling, Jak-STAT signaling, apoptosis, and many other signaling pathways. As an important molecular PI3K/Akt pathway downstream CCND1and PDCD4can be coordinated regulation of miR-21, miR-183*, miR-101and miR-19b, miR-27b, miR-451and miR-107and miR-1290and miR-1246and miR-1260, promoting apoptosis, play a role of anti-tumor in paclitaxel chemotherapy. Paclitaxel chemotherapy affects normal liver cells, the down-regulated miRNA gene function were enriched in cell morphology and development, their toxicity function associated with gastrointestinal toxicity, blood disease and renal toxicity reaction, so they could become predictive markers for monitoring clinical adverse reactions. Further investigation of these changes by miRNAs regulation pathway is our next step. Manipulation of one or more of these miRNAs could be an important approach for paclitaxel therapy.