RESUMEN
PURPOSE: To investigate the role of NRF2 signalling in conferring superior prognosis in patients with HPV positive (HPV+ve) head & neck squamous cell carcinomas (HNSCC) compared to HPV negative (HPV-ve) HNSCC and develop molecular markers for selection of HPV+ve HNSCC patients for treatment de-escalation trials. METHODS: NRF2 activity (NRF2, KEAP1, and NRF2-transcriptional targets), p16, and p53 levels between HPV+ve HNSCC and HPV-ve HNSCC in prospective and retrospective tumor samples as well as from TCGA database were compared. Cancer cells were transfected with HPV-E6/E7 plasmid to elucidate if HPV infection represses NRF2 activity and sensitizes to chemo-radiotherapy. RESULTS: Prospective analysis revealed a marked reduction in expression of NRF2, and its downstream genes in HPV+ve tumors compared to HPV-ve tumors. A retrospective analysis by IHC revealed significantly lower NQO1 in p16high tumors compared to p16low tumors and the NQO1 expression correlated negatively with p16 and positively with p53. Analysis of the TCGA database confirmed low constitutive NRF2 activity in HPV+ve HNSCC compared to HPV-ve HNSCC and revealed that HPV+ve HNSCC patients with 'low NQO1' expression showed better overall survival compared to HPV+ve HNSCC patients with 'high NQO1' expression. Ectopic expression of HPV-E6/E7 plasmid in various cancer cells repressed constitutive NRF2 activity, reduced total GSH, increased ROS levels, and sensitized the cancer cells to cisplatin and ionizing radiation. CONCLUSION: Low constitutive NRF2 activity contributes to better prognosis of HPV+ve HNSCC patients. Co-expression of p16high, NQO1low, and p53low could serve as a predictive biomarker for the selection of HPV + ve HNSCC patients for de-escalation trials.
Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Virus del Papiloma Humano , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Neoplasias de Cabeza y Cuello/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/metabolismo , Carcinoma de Células Escamosas/metabolismo , Estudios Retrospectivos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismoRESUMEN
INTRODUCTION: Annona muricata (L.) (AM), commonly known as Soursop and Lakshmanaphala/Hanumaphala in India, has been extensively used in ethnomedicine for treating tuberculosis, urinary tract infections (UTIs) and cancers. The fruit is a rich source of antioxidants and antitumor agents. METHODS: In this study, we have extracted phytochemicals that exhibited anti-cancer property from the (a) fruit pulp using methanol (AMPM) and water (AMPW); and (b) seeds using methanol (AMSM). Qualitative phytochemical analysis showed the presence of phenolics, tannins, alkaloids, flavonoids, sterols, terpenoids, carbohydrates and proteins in AMPM and AMPW. All three extracts were first checked for in vitro antioxidant and anti-inflammatory properties and then tested for efficacy against MCF-7 and MDA-MB-231. RESULTS: Among these three extracts, AMSM showed the highest antioxidant power as well as ~80% inhibition at 320µg/ml concentration in both cell lines upon treatment for 24h. However, only about 40% inhibition was observed with 320µg/ml AMPM treatment, despite its highest anti-inflammatory potential. Water extract AMPW exhibited about 80% growth inhibition at 50% dilution. Since fruit pulp is the one consumed, the extracts AMPM and AMPW were further tested for apoptosis induction and cell cycle arrest. Analysis of the data showed increased apoptosis and G0/G1 cell cycle arrest upon exposure to AMPM and AMPW.
Asunto(s)
Annona/química , Neoplasias de la Mama/tratamiento farmacológico , Frutas/química , Extractos Vegetales/farmacología , Semillas/química , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Flavonoides/farmacología , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Fase de Descanso del Ciclo Celular/efectos de los fármacosRESUMEN
Patients with HPV associated (HPV+ve) head and neck squamous cell carcinoma (HNSCC), particularly oropharyngeal cancer, show better treatment response, higher survival rates, and lower risks of recurrence as compared to HPV-ve HNSCC patients. Despite increased sensitivity to treatment modality, HPV+ve HNSCC patients are subjected to the same intensive anti-cancer therapy as HPV-ve HNSCC patients and thus subjecting them to unwarranted long-term toxicity. To identify predictive biomarkers for risk-stratification, we have analyzed the mutational spectrum, and the evidence suggests that gain-of-function mutations in the NRF2 pathway are highly prevalent in HPV-ve HNSCC. At the same time, it is rare in HPV+ve HNSCC tumors. We have reviewed the importance of gain-of-NRF2 function and loss of p53 in the prognosis of HNSCC patients and discussed a predictive scoring system using a combination of HPV status (p16), NRF2 pathway and p53 to stratify HPV+ve HNSCC into good versus poor responders, which could immensely help in guiding future de-escalation treatment approaches in patients with HPV+ve HNSCC.