RESUMEN
Immune checkpoint blockade therapy has changed prognoses for many melanoma patients. However, immune responses that correlate with clinical progression of the disease are still poorly understood. To identify immune responses correlating with melanoma clinical evolution, we analyzed serum cytokines as well as circulating NK and T-cell subpopulations from melanoma patients. The patients' immune profiles suggested that melanoma progression leads to changes in peripheral blood NK and T-cell subsets. Stage IV melanoma was characterized by an increased frequency of CCR7+CD56bright NK cells as well as high serum concentrations of the CCR7 ligand CCL19. CCR7 expression and CCL19 secretion were also observed in melanoma cell lines. The CCR7+ melanoma cell subpopulation coexpressed PD-L1 and Galectin-9 and had stemness properties. Analysis of melanoma-derived cancer stem cells (CSC) showed high CCR7 expression; these CSCs were efficiently recognized and killed by NK cells. An accumulation of CCR7+, PD-L1+, and Galectin-9+ melanoma cells in melanoma metastases was demonstrated ex vivo Altogether, our data identify biomarkers that may mark a CCR7-driven metastatic melanoma pathway.
Asunto(s)
Células Asesinas Naturales/inmunología , Melanoma/inmunología , Antígeno B7-H1/inmunología , Línea Celular , Quimiocina CCL19/inmunología , Técnicas de Cocultivo , Citocinas/sangre , Femenino , Galectinas/inmunología , Humanos , Masculino , Melanoma/sangre , Melanoma/patología , Células Madre Neoplásicas/inmunología , Receptores CCR7/inmunologíaRESUMEN
Ferritin is a nanocage protein composed by the variable assembly of 24 heavy and light subunits. As major intracellular iron storage protein, ferritin has been studied for many years in the context of iron metabolism. However, recent evidences have highlighted its role, in particular that of the heavy subunit (FHC), in pathways related to cancer development and progression, such as cell proliferation, growth suppressor evasion, cell death inhibition, and angiogenesis. At least partly, the involvement in these pathways is due to the ability of FHC to control the expression of a repertoire of oncogenes and oncomiRNAs. Moreover, the existence of a feedback loop between FHC and the tumor suppressor p53 has been demonstrated in different cell types. Here, we show that ectopic over-expression of FHC induces the promoter hypermethylation and the down-regulation of miR-125b that, in turn, enhances p53 protein expression in non-small cell lung cancer (NSCLC) cell lines. Notably, analysis by absolute quantitative RT-PCR of FHC, miR-125b, and p53 strongly suggests that this axis might be active in human NSCLC tissue specimens. In vitro, FHC over-expression attenuates survival of NSCLC cells by inducing p53-mediated intrinsic apoptosis that is partially abrogated upon miR-125b re-expression. Overall, our findings demonstrate that FHC acts as a tumor suppressor gene, thus providing a potential molecular strategy for induction of NSCLC apoptotic cell death.
Asunto(s)
Adenocarcinoma del Pulmón/genética , Apoferritinas/genética , Carcinoma de Células Grandes/genética , Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , MicroARNs/genética , Proteína p53 Supresora de Tumor/genética , Células A549 , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Adulto , Anciano , Apoferritinas/metabolismo , Apoptosis/genética , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular , Retroalimentación Fisiológica , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
OBJECTIVES: Ferritin is the major intracellular iron storage protein essential for maintaining the cellular redox status. In recent years ferritin heavy chain (FHC) has been shown to be involved also in the control of cancer cell growth. Analysis of public microarray databases in ovarian cancer revealed a correlation between low FHC expression levels and shorter survival. To better understand the role of FHC in cancer, we have silenced the FHC gene in SKOV3 cells. RESULTS: FHC-KO significantly enhanced cell viability and induced a more aggressive behaviour. FHC-silenced cells showed increased ability to form 3D spheroids and enhanced expression of NANOG, OCT4, ALDH and Vimentin. These features were accompanied by augmented expression of SCD1, a major lipid metabolism enzyme. FHC apparently orchestrates part of these changes by regulating a network of miRNAs. METHODS: FHC-silenced and control shScr SKOV3 cells were monitored for changes in proliferation, migration, ability to propagate as 3D spheroids and for the expression of stem cell and epithelial-to-mesenchymal-transition (EMT) markers. The expression of three miRNAs relevant to spheroid formation or EMT was assessed by q-PCR. CONCLUSIONS: In this paper we uncover a new function of FHC in the control of cancer stem cells.