RESUMO
We report the case of a 46-year-old woman with Bloom-like syndrome affected with locally advanced cervical cancer. She was treated with induction chemotherapy and radical radiation therapy concurrent with chemotherapy (carboplatin and paclitaxel). She was able to complete treatment, but grade III toxicities were observed. The limited relevant literature is presented. We conclude that the management of patients with DNA repair deficiency is challenging for the team in charge because of the potentially high sensitivity to treatment and the lack of clear recommendations in the literature. The main objective remains to deliver the optimal treatment while reducing toxicities.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo do Útero/radioterapia , Carboplatina/uso terapêutico , Paclitaxel/uso terapêuticoRESUMO
Patients with EGFR-mutated non-small cell lung cancer (NSCLC) benefit from treatment with tyrosine kinase inhibitors (TKI) targeting EGFR. Despite improvements in patient care, especially with the 3rd generation TKI osimertinib, disease relapse is observed in all patients. Among the various processes involved in TKI resistance, epithelial-to-mesenchymal transition (EMT) is far from being fully characterized. We hypothesized that the cellular prion protein PrPC could be involved in EMT and EGFR-TKI resistance in NSCLC. Using 5 independent lung adenocarcinoma datasets, including our own cohort, we document that the expression of the PRNP gene encoding PrPC is associated with EMT. By manipulating the levels of PrPC in different EGFR-mutated NSCLC cell lines, we firmly establish that the expression of PrPC is mandatory for cells to maintain or acquire a mesenchymal phenotype. Mechanistically, we show that PrPC operates through an ILK-RBPJ cascade, which also controls the expression of EGFR. Our data further demonstrate that PrPC levels are elevated in EGFR-mutated versus wild-type tumours or upon EGFR activation in vitro. In addition, we provide evidence that PRNP levels increase with TKI resistance and that reducing PRNP expression sensitizes cells to osimertinib. Finally, we found that plasma PrPC levels are increased in EGFR-mutated NSCLC patients from 2 independent cohorts and that their longitudinal evolution mirrors that of disease. Altogether, these findings define PrPC as a candidate driver of EMT-dependent resistance to EGFR-TKI in NSCLC. They further suggest that monitoring plasma PrPC levels may represent a valuable non-invasive strategy for patient follow-up and warrant considering PrPC-targeted therapies for EGFR-mutated NSCLC patients with TKI failure.