RESUMO
INTRODUCTION: Long intergenic noncoding RNA-p21 (lincRNA-p21) is a long noncoding RNA transcriptionally activated by tumor protein p53 (TP53) and hypoxia inducible factor 1 alpha subunit (HIF1A). It is involved in the regulation of TP53-dependent apoptosis and the Warburg effect. We have investigated the role of lincRNA-p21 in NSCLC. METHODS: LincRNA-p21 expression was assessed in tumor and normal tissue from 128 patients with NSCLC and correlated with time to relapse and cancer-specific survival (CSS). H23, H1299, and HCC-44 cell lines were cultured in hypoxic conditions after silencing of lincRNA-p21. The TaqMan human angiogenesis array was used to explore angiogenesis-related gene expression. Levels of the protein vascular endothelial growth factor A were measured by enzyme-linked immunosorbent assay in the cell supernatants. Angiogenic capability was measured by human umbilical vein endothelial cell tube formation assay. Microvascular density in tumor samples was analyzed by immunohistochemistry. RESULTS: LincRNA-p21 was down-regulated in tumor tissue, but no association was observed with TP53 mutational status. High lincRNA-p21 levels were associated with poor CSS in all patients (p = 0.032). When patients were classified according to histological subtypes, the impact of lincRNA-p21 was confined to patients with adenocarcinoma in both time to relapse (p = 0.006) and CSS (p < 0.001). To explain the poor outcome of patients with high lincRNA-p21 expression, we studied the role of lincRNA-p21 in angiogenesis in vitro and observed a global downregulation in the expression of angiogenesis-related genes when lincRNA-p21 was inhibited. Moreover, supernatants from lincRNA-p21-inhibited cells were significantly less angiogenic and had lower levels of secreted vascular endothelial growth factor A than controls did. Finally, tumor samples with high lincRNA-p21 levels had higher microvascular density. CONCLUSIONS: Our findings suggest that lincRNA-p21 affects outcome in patients with NSCLC adenocarcinoma through the regulation of angiogenesis.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/metabolismo , TransfecçãoRESUMO
PiwiRNAs, small non-coding RNAs processed by Piwi proteins, are involved in maintaining genome stability in germline cells. Recently, piwiRNA expression has been identified in some tumors. We have examined the potential reactivation of the Piwi/piwiRNA pathway in classical Hodgkin lymphoma (cHL). We found that Piwi proteins and three selected piwiRNAs, including piR-651, were expressed in cHL patients and cell lines, indicating that the Piwi/piwiRNA pathway is active in cHL. Interestingly, low levels of piR-651 were associated with lack of complete response to first-line treatment, as well as shorter disease-free and overall survival in a cohort of 94 cHL patients. At diagnosis, piR-651 was underexpressed in cHL serum samples compared to healthy controls, while after complete remission, piR-651 levels increased to levels similar to healthy controls. This is the first evidence that piwiRNAs are active in tumor and serum samples and impact prognosis in cHL.
Assuntos
Biomarcadores Tumorais/genética , Doença de Hodgkin/patologia , RNA não Traduzido/genética , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Doença de Hodgkin/genética , Doença de Hodgkin/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , TranscriptomaRESUMO
The expression of Piwi-interacting RNAs, small RNAs that bind to PIWI proteins, was until recently believed to be limited to germinal stem cells. We have studied the expression of PIWI genes during human lung embryogenesis and in paired tumor and normal tissue prospectively collected from 71 resected non-small-cell lung cancer patients. The mRNA expression analysis showed that PIWIL1 was highly expressed in 7-week embryos and downregulated during the subsequent weeks of development. PIWIL1 was expressed in 11 of the tumor samples but in none of the normal tissue samples. These results were validated by immunohistochemistry, showing faint cytoplasmic reactivity in the PIWIL1-positive samples. Interestingly, the patients expressing PIWIL1 had a shorter time to relapse (TTR) (p = 0.006) and overall survival (OS) (p = 0.0076) than those without PIWIL1 expression. PIWIL2 and 4 were downregulated in tumor tissue in comparison to the normal tissue (p < 0.001) and the patients with lower levels of PIWIL4 had shorter TTR (p = 0.048) and OS (p = 0.033). In the multivariate analysis, PIWIL1 expression emerged as an independent prognostic marker. Using 5-Aza-dC treatment and bisulfite sequencing, we observed that PIWIL1 expression could be regulated in part by methylation. Finally, an in silico study identified a stem-cell expression signature associated with PIWIL1 expression.
Assuntos
Proteínas Argonautas/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Pulmão/metabolismo , Idoso , Idoso de 80 Anos ou mais , Proteínas Argonautas/genética , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Linhagem Celular Tumoral , Metilação de DNA , Progressão da Doença , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pulmão/embriologia , Pulmão/cirurgia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Modelos de Riscos Proporcionais , Proteínas de Ligação a RNA , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
Epigenetic mechanisms are crucial for the inactivation of key genes related to the survival of Hodgkin lymphoma (HL) cells, and methylation is a frequent epigenetic mechanism of microRNA silencing. We have examined the methylation-induced silencing of tumor suppressor microRNAs in HL cell lines and confirmed our results in patient lymph nodes. In addition, we evaluated the in vitro effectiveness of 5-aza-2-deoxycytidine (5-Aza-dC) in HL cell lines. Ten microRNAs containing CpG islands in their promoter region were re-expressed in both the L-428 and L-1236 cell lines. Interestingly, miR-34a and miR-203, both known tumor suppressor microRNAs, were found to be methylated in cell lines and in patient samples. 5-Aza-dC treatment resulted in a dose-dependent antiproliferative effect at 72 h in all the HL cell lines. In summary, 5-Aza-dC treatment of HL cell lines inhibits proliferation at high doses and produces re-expression of the tumor suppressor microRNAs at low-intermediate doses.
Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/genética , MicroRNAs/genética , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Análise por Conglomerados , Metilação de DNA , Decitabina , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Doença de Hodgkin/patologia , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Regiões Promotoras Genéticas , Reprodutibilidade dos Testes , TranscriptomaRESUMO
Single nucleotide polymorphisms (SNPs) in 12 genes involving multidrug resistance, drug metabolic pathways, DNA repair systems and cytokines were examined in 28 patients with relapsed/refractory multiple myeloma (MM) treated with single agent thalidomide and the results were correlated with response, toxicity and overall survival (OS). The response rate was higher in patients with SNPs in ERCC1 (rs735482) (p=0.006), ERCC5 (rs17655) (p=0.04) or XRCC5 (rs1051685) (p=0.013). Longer OS was associated with the SNP in ERCC1 (rs735482) (p=0.005) and XRCC5 (rs1051685) (p=0.02). Finally, polymorphism in GSTT1 (rs4630) was associated with a lower frequency of thalidomide-induced peripheral neuropathy (p=0.04).