Germline BRCA1/2 alteration has been linked to an increased risk of hereditary breast and ovarian cancer syndromes. As a result, genetic testing, based on NGS, allows us to identify a high number of variants of uncertain significance (VUS) or conflicting interpretation of pathogenicity (CIP) variants. The identification of CIP/VUS is often considered inconclusive and clinically not actionable for the patients’ and unaffected carriers’ management. In this context, their assessment and classification remain a significant challenge. The aim of the study was to investigate whether the in silico prediction tools (PolyPhen-2, SIFT, Mutation Taster and PROVEAN) could predict the potential clinical impact and significance of BRCA1/2 CIP/VUS alterations, eventually impacting the clinical management of Breast Cancer subjects. In a cohort of 860 BC patients, 10.6% harbored BRCA1 or BRCA2 CIP/VUS alterations, mostly observed in BRCA2 sequences (85%). Among them, forty-two out of fifty-five alterations were predicted as damaging, with at least one in silico that used tools. Prediction agreement of the four tools was achieved in 45.5% of patients. Moreover, the highest consensus was obtained in twelve out of forty-two (28.6%) mutations by considering three out of four in silico algorithms. The use of prediction tools may help to identify variants with a potentially damaging effect. The lack of substantial agreement between the different algorithms suggests that the bioinformatic approaches should be combined with the personal and family history of the cancer patients.

The BCR-ABL1 chimeric oncoprotein plays a pivotal role in the pathogenesis of Chronic Myeloid Leukemia (CML) as its constitutive kinase activity transforms the hematopoietic stem cell, promoting pro-survival signaling. We and others have previously shown that the manipulation of BCR-ABL1 catalytic activity modulates its intracellular localization, thereby transforming the culprit of CML into a pro-apoptotic protein that selectively kills leukemic cells. Here, we investigated the role of the BCR coiled-coil and C2 domains on BCR-ABL1 intracellular localization and leukemogenic potential. We performed a bioinformatic analysis that identified two putative nuclear localization signals (NLSs) in BCR. Using recombinant DNA strategies, we generated multiple BCR and BCR-ABL1 mutants that were ectopically expressed in human cells. The intracellular localization of each construct was analyzed by immunofluorescence, while their biological activity was investigated employing proliferation and transforming assays. We show that BCR displays two nuclear localization signals functionally inactivated by the coiled-coil and C2 domains. The removal of these regions reactivated the nuclear migration of both BCR and BCR-ABL1 mutants. Moreover, BCR-ABL1 constructs devoid of the coiled-coil and C2 domains displayed reduced transforming potential in Ba/F3 cells and in primary human CD34+ progenitors. Finally, we demonstrate that the deletion of the C2 domain compromises TKI efficacy. Our findings identify two nuclear localization signals in the BCR sequence that are functionally suppressed by the coiled-coil and C2 domains. Targeting these regions may provide additional therapeutic strategies to manipulate both BCR-ABL1 intracellular localization and kinase activity.

Pharmacogenetics has transformed oncology by enabling personalized, effective and safer use of anticancer therapies. Among clinically relevant pharmacogenetic biomarkers, polymorphisms in the UGT1A1 gene influence the metabolism of irinotecan and other SN-38-based agents, increasing the risk of treatment-related toxicities. Beyond SN-38-based therapies, UGT1A1 contributes to the metabolism of endogenous compounds and several drugs, and its activity may be affected by concomitant inhibitors or inducers, highlighting its broader clinical relevance. Although substantial evidence supports the association between UGT1A1 genotype and drug safety, implementation of genotype-guided treatment remains inconsistent. This narrative review summarizes the biological basis and clinical relevance of UGT1A1 polymorphisms in patients receiving SN-38-based therapies. Original studies, systematic reviews, meta-analyses, and international and regional pharmacogenetic guidelines were evaluated regarding genotype-guided dosing, clinical outcomes, implementation strategies, and barriers to routine testing. Reduced-function UGT1A1 variants are associated with increased risk of irinotecan-induced neutropenia and diarrhea, particularly at higher doses. However, recommendations from scientific societies differ regarding testing indications, dose adjustment strategies, and patient selection. Uncertainties remain concerning the clinical implications of UGT1A1 variability for newer antibody–drug conjugates carrying an SN-38 payload. Practical barriers, including inconsistent guideline recommendations, limited access to testing, reimbursement issues, and heterogeneous clinical workflows, continue to restrict implementation. UGT1A1 genotyping represents a valuable tool for improving the safety of selected anticancer therapies, yet its incorporation into clinical practice remains incomplete. As precision oncology evolves, pharmacogenetic testing may optimize treatment selection, reduce toxicity, and improve outcomes. Further harmonization of international recommendations, high-quality prospective studies, and wider access to pharmacogenetic testing are needed to support routine implementation.