70ROLE OF PLATINUM DRUGS AND THEIR RESISTANCE IN OVARIAN AND BREAST CANCER CELL LINESTo understand the role of Platinum drugs as chemotherapeutic agents and to determine the mechanism involved in the development of resistance to Platinum drugs in certain Ovarian and Breast cancer cell lines(A2780, HEY, OVCAR-8, SKOV-3, and BG-1 ovarian cancer cell lines and MCF-7 breast cancer cells), thus limiting the chemotherapy of theses alkylating agents. All Publications describing ―Resistance to Platinum drugs in breast and ovarian cancer‖ were searched in Medline and Cochrane collaboration. The search yielded 320 references, of which only 46 references were considered as we couldn’t retrieve several case reports and few retrospective studies. The included references mainly focused on development of resistance to platinum drugs and the mechanism that might have caused such resistance. Emergence of chemo resistance phenotype is the formidable prospect of chemotherapy in ovarian and breast cancer cell lines. Several mechanisms for development of resistance have been proposed and it can occur due to inadequate levels of platinum reaching target DNA, as well as after DNA attachment due to increased NER (nucleotide-excision repair) especially through increased activity of the endonuclease protein ERCC1 (excision repair cross-complementing-1) and can lead to platinum drug resistance (as adducts are removed before apoptotic signalling pathways are triggered). Cisplatin with thiol-groups form a virtually insoluble sulphide and this mechanism of action in resistance formation is exclusive to platinum-based compounds. Signal transducer and activator of transcription 3 (STAT3) overexpression has also been reported positively associated with cisplatin resistance. Emergence of chemo resistance phenotype is the formidable prospect of chemotherapy in ovarian and breast cancer cell lines (A2780, HEY, OVCAR-8, SKOV-3, and BG-1 ovarian cancer cell lines and MCF-7 breast cancer cells). Development of resistance is a hindrance to providing effective chemotherapy. Understanding the mechanism involved in resistance is of vital importance in developing therapies that overcome such resistancenareshtalakola@gmail.comReview432014Resistance,Platinum Drugs,Cisplatin,Ovarian Cancer,Breast CancerT.Naresh,A.Sandeep,B.Devi Prasad,S.vishwanathanIntern Doctor of Pharmacy,Rajah Muthiah Medical College Hospital, Annamalai University, Annamalainagar, India 608002.,Intern Doctor of Pharmacy,Rajah Muthiah Medical College Hospital, Annamalai University, Annamalainagar, India 608002.,Intern Doctor of Pharmacy,Rajah Muthiah Medical College Hospital, Annamalai University, Annamalainagar, India 608002.,Professor and Medical Superintendent, Rajah Muthiah Medical College Hospital, Annamalai University, Annamalainagar, India 608002.