Thèse de doctorat
Résumé : SUMMARYThe diversity of cancer molecular origins associated with the genetic variability of patients has encouraged the development of chemotherapeutic treatments adapted not only to the target tumor, but also to a specific patient. This personalized strategy is based on cancer biomarkers allowing a better identification and characterization of each tumor where predictive biomarkers provide the distinction between various factors indicative of the response to the treatment. In this context, several studies highlighted the role of the solute carrier transporter family 22 (solute carriers 22 or SLC22) in the uptake of platinum anticancer drugs. This mechanism being not well understood, our work intends to establish the potential role of SLC22 member A18 (SLC22A18) as predictive biomarker in the aim to help to a better targeted chemotherapeutic strategy for each patient. We optimized a system overexpressing SLC22A18 stably or transiently in HeLa cancer cell line. SLC22A18 expression was confirmed by qRT-PCR, western blotting, microscopy and flow cytometry. The cell lines were treated with taxane, anthracyclin, vinca alkaloid and nitrosoureas anticancer drug families. We showed that doxorubicin, camptothecin, chloroquine, tetracycline and carmustin had no effect on the cell viability assays suggesting that they are not substrates of SLC22A18. Interestingly, the cell line was sensitized in the presence of antimitotic drug with a sensitivity factor of 2.7 in the presence of paclitaxel, 1.4 with docetaxel, 1.8 with vinblastin and 2.2 in the presence of vincristine. To confirm these results, we elaborated a SLC22A18 knockdown cell line in HS683 cells using siRNA technology. The downexpression of SLC22A18 was correlated to a tendency to resist to the accumulation of paclitaxel thereby confirming the previous results. Simultaneously, a knockout cell line was established using the transcription activator-like effectors nuclease (TALEN) technology in U373 cell line. Our studies constitute a robust base of knowledge for further investigation on SLC22A18 transporter as a predictive biomarker promoting antimitotic treatment in tumors where this transporter is detected.