'Genetic profiling' and ovarian cancer therapy (review)

High variability observed among ovarian cancer patients in response to the same therapy and the related toxicity may be correlated to gene polymorphisms and genetic alterations affecting the metabolism of drugs commonly used to treat this tumor. Recent studies have shown a correlation between the polymorphisms characterizing GSTM1-T1 detoxifying enzymes and poor outcome in advanced ovarian cancer patients treated with platinum/paclitaxel-based chemotherapy. Multidrug resistance 1 (mdr-1) polymorphisms were found to be associated with resistance to paclitaxel treatment. Polymorphisms of MRP2, a protein involved in methotrexate, cisplatin and irinotecan active metabolite glucuronide transport, negatively affect platinum-based chemotherapy response. A similar occurrence has been observed with CYP1A1 Ile462Val and ercc1 C118T polymorphisms while patients who were carriers of MTHFR C677T polymorphism had a better response to methotrexate therapy, but an elevated risk of toxicity. Biological therapy with Bevacizumab, the anti-vascular endothelial growth factor has been shown to be less efficient in ovarian cancer patients carrying the polymorphism of the Interleukin-8 gene. Instead, polymorphisms in the XPD gene (Lys751Gln and Asp312Asn), a member of the nucleotide excision repair pathway, positively affects the response to therapy with carboplatin/paclitaxel. Therefore, the study of 'genetic profiling' is crucial to improving the clinician's ability to tailor effective therapy to the molecular profile of the patient while minimizing toxicities. This review describes clinical applications of the above genetic polymorphisms in ovarian cancer patients treated with platinum/paclitaxel-based chemotherapy.