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Abstract Background Breast Cancer (BC) can be classified, due to its heterogeneity, into multiple subtypes that differ for prognosis and clinical management. Notably, triple negative breast cancer (TNBC) – the most aggressive BC form – is refractory to endocrine and most of the target therapies. In this view, taxane-based therapy still represents the elective strategy for the treatment of this tumor. However, due variability in patients’ response, management of TNBC still represents an unmet medical need. Telomeric Binding Factor 2 (TRF2), a key regulator of telomere integrity that is over-expressed in several tumors, including TNBC, has been recently found to plays a role in regulating autophagy, a degradative process that is involved in drug detoxification. Based on these considerations, we pointed, here, at investigating if TRF2, regulating autophagy, can affect tumor sensitivity to therapy. Methods Human TNBC cell lines, over-expressing or not TRF2, were subjected to treatment with different taxanes and drug efficacy was tested in terms of autophagic response and cell proliferation. Autophagy was evaluated first biochemically, by measuring the levels of LC3, and then by immunofluorescence analysis of LC3-puncta positive cells. Concerning the proliferation, cells were subjected to colony formation assays associated with western blot and FACS analyses. The obtained results were then confirmed also in mouse models. Finally, the clinical relevance of our findings was established by retrospective analysis on a cohort of TNBC patients subjected to taxane-based neoadjuvant chemotherapy. Results This study demonstrated that TRF2, inhibiting autophagy, is able to increase the sensitivity of TNBC cells to taxanes. The data, first obtained in in vitro models, were then recapitulated in preclinical mouse models and in a cohort of TNBC patients, definitively demonstrating that TRF2 over-expression enhances the efficacy of taxane-based neoadjuvant therapy in reducing tumor growth and its recurrence upon surgical intervention. Conclusions Based on our finding it is possible to conclude that TRF2, already known for its role in promoting tumor formation and progression, might represents an Achilles’ heel for cancer. In this view, TRF2 might be exploited as a putative biomarker to predict the response of TNBC patients to taxane-based neoadjuvant chemotherapy.

Transgender individuals exhibit a higher prevalence of cancer-related risk factors, such as substance abuse and sexually transmitted infections. These factors, coupled with suboptimal adherence to cancer screening recommendations, may lead to a higher incidence of cancers, such as breast and cervical cancer, and contribute to delayed diagnoses in transgender patients. Herein, we report a unique case of a transgender man with a history of alcohol and drug abuse, undergoing gender-affirming exogenous testosterone therapy, who developed synchronous locally advanced breast cancer and human papilloma virus (HPV)-related cervical cancer. He underwent concurrent chemoradiation for cervical cancer and surgery followed by endocrine therapy for breast cancer. The treatments were suboptimals due to patient’s comorbidities, among them liver cirrhosis leading to an early death. Additionally, we have conducted a review of existing literature, including case reports, clinical studies, and review articles investigating the role of potential risk factors specifically related to breast and cervical tumors in transgender men. Gender-affirming testosterone therapy is common among transgender men to induce gender affirmation, but its link to breast cancer risk remains ambiguous, with studies being limited and sometimes contradictory. Conversely, HPV is a well-established cause of up to 99% of cervical cancers. Despite persistent risk for cervical cancer in transgender men who retain their cervix, several studies indicate notable disparities in screening adherence, due to personal and structural barriers. Moreover, alcohol and drug use disorders, commonly encountered in transgender population, may negatively influence the adherence to screening programs. Current cancer screening guidelines for this population are somewhat unclear, and specific programs based on more robust data are urgently required along with further tailored studies.