Mechanisms of acquired resistance of BRCA1/2-driven tumors to platinum compounds and PARP inhibitors

Molecular pathogenesis of tumors arising in BRCA1/2 germ-line mutation carriers usually includes somatic inactivation of the remaining allele of the involved gene.Consequently,BRCA1/2-driven cancers are sensitive to platinum-based therapy and poly(ADP-ribose)polymerase inhibitors(PARPi).Long-term exposure to these drugs may result in the emergence of secondary BRCA1/2 mutations,which restore the open-reading frame of the affected allele.This platinum/PARPi crossresistance mechanism applies both for BRCA1 and BRCA2 genes and has been repeatedly validated in various laboratory models and multiple clinical studies.There are some other routes associated with the partial rescue of BRCA1/2 function or the development of BRCA1/2-independent pathways for genomic maintenance;however,their actual clinical relevance remains to be established.In addition,studies on the short-term neoadjuvant therapy for ovarian cancer revealed that even chemonaive BRCA1-driven tumors contain a small proportion of BRCA1-proficient cells.These pre-existing cells with retained BRCA1 heterozygosity rapidly repopulate the tumor mass during platinum exposure,but become outcompeted by BRCA1-deficient cells during therapy holidays.Understanding of the platinum/PARPi resistance pathways has led to the development of novel therapeutic approaches,which aim to improve the management of BRCA1/2-related cancers and are currently undergoing preclinical and clinical evaluation.

Uncertainty following an inconclusive result from the BRCA1/2 genetic test:A review about psychological outcomes

BACKGROUND An inconclusive result from BRCA1/2 genetic testing indicates that a genetic variant of uncertain significance is detected.This case constitutes the majority of genetic test results,but studies specifically addressing the psychological adjustment of people with inconclusive results are scarce.AIM To examine psychological outcomes of receiving an uninformative BRCA1/2 test result.METHODS PubMed,PsychInfo,and Cochrane Central Register of Controlled Trials were screened for studies focusing on distress,anxiety,and depression levels in individuals with inconclusive genetic test results.This review is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method.RESULTS Studies on psychological outcomes of inconclusive BRCA1/2 focused on general and specific distress,anxiety,and depression.Overall,they produced mixed results.These inconsistent findings are probably due to the uncertainty caused by this type of result,that may also influence the decisions of individuals about surveillance and prophylactic options,reducing their compliance.In addition,this review highlights specific risk and protective factors that affect psychological adjustment in individuals with an inconclusive genetic testing result.CONCLUSION Individuals with inconclusive genetic test results need specific educational programs and support to better understand the meaning of their results in order to be able to make decisions about surveillance and prophylactic options.