RESUMO
Circular RNA (circRNA) is a large class of covalently closed circRNA. As a member of competitive endogenous RNA, it participates in the regulation of circRNA-miRNA-mRNA network and plays an important role in the regulation of physiology and pathology. CircRNA is produced by the reverse splicing of exon, intron or both, forming exon or intron circRNA. Studies have shown that circRNA is a ubiquitous molecule, which exceeds the linear mRNA distributed in human cells. Because of its covalent closed-loop structure, circRNA is resistant to RNase R, which is more stable than linear mRNA; circRNA is highly conserved in different species. It was found that circRNA competitively adsorbs miRNA, as a miRNA sponge, to involve in the expression regulation of a variety of genes and plays an important role in tumor development, invasion, metastasis and other processes. These molecules offer new potential opportunities for therapeutic intervention and serve as biomarkers for diagnosis. In this paper, the origin, characteristics and functions of circRNA and its role in tumor development, invasion and metastasis, diagnosis and prognosis are reviewed.
Assuntos
Neoplasias/terapia , Medicina de Precisão , RNA Circular , Carcinogênese/genética , Éxons , Humanos , Íntrons , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/diagnóstico , Neoplasias/patologia , Neoplasias/virologia , Conformação de Ácido Nucleico , Prognóstico , RNA Circular/química , RNA Circular/genética , RNA Circular/fisiologiaRESUMO
OBJECTIVE: To investigate the clinical value of the expression of glucose regulated protein 78 (GRP78) for assessment of severity, chemoresistance and prognosis in patients with gastric adenocarcinoma ( GC) . METHODS: A cohort of 237 patients with gastric cancer was included in this study. 160 patients of them were treated by D2 radical gastrectomy and adjuvant chemotherapy. The GRP78 expression was detected by immunohistochemistry and 80 patients of them were tested in vitro for cancer chemosensitivity by ATP-tumor chemosensitivity assay (ATP-TCA). In addition, the relationships were analyzed between GRP78 and age, gender, tumor differentiation, invasion, disease stage, lymph node metastasis and chemoresistance as well as disease-free survival (DFS). RESULTS: The positive rate of GRP78 expression in the gastric adenocarcinoma was 68.8% before the initiation of chemotherapy. The positive GRP78 expression was significantly correlated with tumor invasion depth, poor differentiation, TNM stages, and lymph node metastasis (all P < 0.05), not correlated with gender and age, and high GRP78 expression was associated with the chemoresistance of the gastric cancer cells to chemotherapeutic agents. Negative GRP78 expression was associated with higher sensitivity to both drugs and regimens. The DFS of GRP78-positive group and GRP78-negative group was (53.6 ± 0.9) months and (38.3 ± 0.8) months, respectively (P = 0.041). Interestingly, subgroup analysis revealed that the DFS in GRP78-negative and-positive patients treated with taxane-containing chemotherapy was (58.6 ± 2.6) months and (49.1 ± 2.7) months, respectively, but the difference was statistically not significant (P = 0.111). In contrast, in the subset of GRP78-negative and- positive patients treated with taxane-containing regimens, the DFS was (45.5 ± 1.9) months and (35.1 ± 2.2) months, respectively, showing a significant difference (P = 0.038). In the group of patients with positive GRP78 expression, the patients treated with taxane-containing chemotherapy had a longer DFS [(49.1 ± 2.7) months] than those without that treatment [(35.1 ± 2.2) months], showing a significant difference (P = 0.017). Univariate analysis revealed that DFS was correlated with histological grade, GRP78 expression and lymph node metastasis (all P < 0.05). Multivariate analysis showed that GRP78 expression and TNM staging were independent influencing factors for gastric cancer (both P < 0.05). CONCLUSIONS: The results of our study suggest that GRP78 may be a novel biomarker for assessment of malignant degree and prediction of chemoresistance in gastric cancer, and may be helpful to chemotherapy planning and prognosis prediction in patients with gastric cancer.
Assuntos
Adenocarcinoma/metabolismo , Proteínas de Choque Térmico/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Quimioterapia Adjuvante , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos , Chaperona BiP do Retículo Endoplasmático , Feminino , Gastrectomia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxoides/administração & dosagemRESUMO
BACKGROUND: Improvements in screening and imaging technologies and treatment of liver disease have influenced the trend in diagnosis for stage I liver cancer. In this article, recent trends in age, incidence, tumour size, and survival of different stages of liver cancer are analysed. METHODS: Surveillance, Epidemiology, and end results data from the National Cancer Institute were used to analyse trends in age-adjusted incidence rate, mean tumour size at diagnosis, age at diagnosis, and 5-year survival probability for stage I liver cancer. RESULTS: Stage I cases of liver cancer increased most tremendously over the study period, with a greater increase from 2004 to 2012 following a smaller increase from 2012 to 2015. Moreover, the mean age of stage I liver cancer increased by 1.72 years from 2004 to 2015. The 5-year-overall survival for stage I liver cases worsened from 97.9% to 83.7% from 2004 to 2011, whereas the 10-year survival probability for stage I cases worsened from 97.3% in 2004 to 79.6% in 2006. Comparing with higher stage cases, stage I liver cancer were more likely to be females, be married, live in metro areas, receive chemotherapy, and carry medical insurance. CONCLUSIONS: The incidence of stage I liver cancer has increased over the study period, with an increase in age of diagnosis, decrease in tumour size, and generally stable overall survival rate with slight decrease. These trends emphasized the importance of early detection of liver cancer and regular screening and better treatment for high-risk populations.RESEARCH HIGHLIGHTSImprovements in screening and imaging technologies and treatment of liver disease have influenced the trend in diagnosis for liver cancer.Stage I cases of liver cancer increased most tremendously over the study period, with a greater increase from 2004 to 2012 following a smaller increase from 2012 to 2015.These trends emphasized the importance of early detection of liver cancer and regular screening and better treatment for high-risk populations.