Rabii Ameziane El Hassani

The Tumor Suppressor BRCA1/2, Cancer Susceptibility and Genome Instability in Gynecological and Mammary Cancers

BRCA1 and BRCA2 germline alterations highly predispose women to breast and ovarian cancers. They are mostly found within the TNBC (Triple-Negative Breast Cancer) and the HGSOC (High-Grade Serous Ovarian Carcinoma) subsets, known by an aggressive phenotype, the lack of therapeutic targets and poor prognosis. Importantly, there is an increased risk for cervical cancer in BRCA1 and BRCA2 mutation carriers that raises questions about the link between the HPV-driven genome instability and BRCA1 and BRCA2 germline mutations. Clinical, preclinical, and in vitro studies explained the increased risk for breast and ovarian cancers by genome instability resulting from the lack or loss of many functions related to BRCA1 or BRCA2 proteins such as DNA damage repair, stalled forks and R-loops resolution, transcription regulation, cell cycle control, and oxidative stress. In this review, we decipher the relationship between BRCA1/2 alterations and genomic instability leading to gynecomammary cancers through results from patients, mice, and cell lines. Understanding the early events of BRCA1/2-driven genomic instability in gynecomammary cancers would help to find new biomarkers for early diagnosis, improve the sensitivity of emerging therapies such as PARP inhibitors, and reveal new potential therapeutic targets.

Human papillomavirus-encoded microRNAs: key regulators in cervical cancer development

Human papillomaviruses (HPVs) cause diverse cutaneous and mucosal diseases, with several genotypes strongly associated with cervical cancer. Beyond the well-established role of cellular microRNAs (miRNAs) in gene regulation, increasing evidence shows that HPV also encodes its own viral miRNAs (v-miRNAs). These v-miRNAs modulate both viral and host gene expression, influencing key pathways involved in oncogenesis, including cell cycle control, apoptosis, immune evasion, and epithelial - mesenchymal transition. By shaping these regulatory networks, HPV-derived miRNAs promote viral persistence and contribute to malignant transformation. Their stability and specificity also make them promising biomarkers for cervical cancer diagnosis and prognosis, although clinical translation remains challenging. This review provides an updated overview of HPV-encoded miRNAs, their validated molecular targets, and their roles in tumour development. It also highlights emerging therapeutic strategies and future perspectives for integrating miRNA-based approaches into precision oncology for HPV-related cervical cancer.