RESUMO
INTRODUCTION: TP53 is the most frequently mutated gene in lung tumors, but its prognostic role in admixed populations, such as Brazilians, remains unclear. In this study, we aimed to evaluate the frequency and clinicopathological impact of TP53 mutations in non-small cell lung cancer (NSCLC) patients in Brazil. METHODS: We analyzed 446 NSCLC patients from Barretos Cancer Hospital. TP53 mutational status was evaluated through targeted next-generation sequencing (NGS) and the variants were biologically classified as disruptive/nondisruptive and as truncating/nontruncating. We also assessed genetic ancestry using 46 ancestry-informative markers. Analysis of lung adenocarcinomas from the cBioportal dataset was performed. We further examined associations of TP53 mutations with patients' clinicopathological features. RESULTS: TP53 mutations were detected in 64.3% (n = 287/446) of NSCLC cases, with a prevalence of 60.4% (n = 221/366) in lung adenocarcinomas. TP53 mutations were associated with brain metastasis at diagnosis, tobacco consumption, and higher African ancestry. Disruptive and truncating mutations were associated with a younger age at diagnosis. Additionally, cBioportal dataset revealed that TP53 mutations were associated with younger age and Black skin color. Patients harboring disruptive/truncating TP53 mutations had worse overall survival than nondisruptive/nontruncating and wild-type patients. CONCLUSION: TP53 mutations are common in Brazilian lung adenocarcinomas, and their biological characterization as disruptive and truncating mutations is associated with African ancestry and shorter overall survival.
Assuntos
Adenocarcinoma de Pulmão , População Negra , Neoplasias Pulmonares , Proteína Supressora de Tumor p53 , Humanos , Adenocarcinoma de Pulmão/etnologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , População Negra/genética , Brasil/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/etnologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/etnologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Mutação , Prevalência , Prognóstico , Proteína Supressora de Tumor p53/genéticaRESUMO
BACKGROUND: Microsatellite instability (MSI) in non-small cell lung cancer (NSCLC) is uncommon; however, most studies refer to European and Asian populations. There are currently no data on MSI frequency in highly admixed populations, such as the one represented by Brazilian NSCLC patients. AIM: This study aimed to evaluate the frequency of MSI in Brazilian NSCLC patients. METHODS: We evaluated 526 patients diagnosed with NSCLC at the Barretos Cancer Hospital (Brazil). The molecular MSI evaluation was performed using a hexa-plex marker panel by polymerase chain reaction followed by fragment analysis. The mutation profile of MSI-positive cases was performed using next-generation sequencing. RESULTS: Only 1 patient was MSI positive (0.19%). This patient was a female, white, and active smoker, and she was diagnosed with clinical stage IV lung adenocarcinoma at 75 years old. The molecular profile exhibited 4 Tumor Protein p53 (TP53) mutations and the absence of actionable mutations in the Epidermal Growth Factor Receptor (EGFR), Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS), or V-Raf Murine Sarcoma Viral Oncogene Homolog B1 (BRAF) genes. CONCLUSIONS: The frequency of MSI in Brazilian NSCLC patients is equally rare, a finding that is consistent with the current literature based on other populations such as Europeans, North Americans, and Asians.