Objective To investigate the expression level and methylation level of micro RNA-34b（miR-34b） gene in papillary thyroid carcinoma （PTC）， and to analyze the relationship between methylation and clinicopathological characters of PTC. Methods PTC tissues and tumor adjacent tissues were collected from 25 patients with PTC who underwent operation in Huai’an First People’s Hospital of Nanjing Medical University from Sep. 2008 to Oct. 2010. Expression of miR-34b gene and level of methylation in gene promoter were detected by real time PCR and methylation-specific PCR in the 2 kinds of tissues， respectively. Results The expression value of miR-34b mRNA in PTC tissues was 0.85±0.05， which was significantly lower than those of tumor adjacent tissues （1.62±0.09）， P=0.030. There were methylation in 18 （72%，18/25） PTC tissues， and 10 （40%，10/25） in tumor adjacent tissues， and the ratio of methylation was higher in PTC tissues （P=0.021）. In PTC tissues， methylation was not related to age， gender， tumor size， TNM stage， and invasion of the capsule （P＞0.05）， but was related to lymph node metastasis （P＜0.05）. Ratio of methylation in patients with lymph node metastasis was significantly higher than those of patients with no lymph node metastasis. Conclusion Methylation of miR-34b gene promoter is one of the reasons for inactivation of PTC， and it may be related to the development and metastasis of PTC， which needs to be further investigated.
Objective To summarize the domestic and abroad articles related to the research on the relation between microRNA （miRNA） and pancreatic cancer，and explore the important effects of miRNA expression patterns in diagnosis of pancreatic cancer. Methods “microRNA and pancreatic cancer” were searched as key words by PubMed and CNKI series full-text database retrieval systems from 2000 to 2012. Totally 60 English papers and 15 Chinese papers were obtained. Choice criteria：the basic research of miRNA and pancreatic cancer，the clinical research of miRNA and pancreatic cancer， and the prospect of miRNA in pancreatic cancer diagnosis and treatment. According to the choice criteria，31 papers were finally analyzed. Results The miRNA expression spectrum and specific miRNA expression such as miR-21，miR-34，miR-217，miR-196a，miR-10a，miR-155，miR-221，miR-222，miR-181a，miR-181b，miR-181d， and the family members of miR-200 and let-7 might be used as tumor markers to differentiate pancreatic cancer from normal pancreas，chronic pancreatitis or pancreatic endocrine tumors，and might be used as prognostic factor to predict the outcome. Conclusions miRNA expression spectrum are not only related to diagnosis of pancreatic cancer， but also have provided a new research direction and method for gene therapy of pancreatic cancer．
Breast cancer is a malignant tumor from normal breast epithelial. In recent years, many literature reports sought to determine the expression of predicted target genes of microRNA and their potential function, pathways and networks, which are involved in the tumorigenesis, metastasis and prognosis of breast cancer. The miR-21 has recently been found to be highly expressed in solid tumors than normal tissue, and it has exposed some layers of gene expression regulation that becomes a hot topic of breast cancer. This paper briefly reviews advances in research on miR-21 in breast cancer.
Objective To summarize the relationship between microRNA and the occurrence and progression of colorectal cancer， and to investigate the application value of microRNA in the diagnosis， treatment， and prognosis evaluation of colorectal cancer. Methods Domestic and international publications involving the relationship between microRNA and colorectal cancer were retrieved and reviewed. Results MicroRNA acted as an oncogene or tumor suppressor gene to participate in cell proliferation， differentiation， apoptosis， metabolism， tumor genesis， and tumor progression. The abnormal expression of microRNA was closely related to the occurrence and progression of colorectal cancer. As specific biomarker， microRNA could be applied in early diagnosis， chemotherapy strategy-making， and prognostic evaluation of colorectal cancer. Conclusion MicroRNA is definitely related to the occurrence and progression of colorectal cancer， and it has great prospect in the basic research and clinical applications of colorectal cancer.
ObjectiveTo quantitate expression of microRNA-21 (miRNA-21) in gastric cancer of different tumor stages and discuss its clinical value. Method The relative expressions of miRNA-21 were quantitated in the cancer tissues, corresponding normal gastric tissues adjacent to gastric cancer, and serums of 50 gastric cancer patients received opera-tion and confirmed gastric cancer by pathology and the serums of nongastric cancer patients in Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine and its Chongming Branch from January 2015 to January 2016 by real time quantitative PCR. ResultsThe relative expression level of miRNA-21 in the gastric cancer tissues was significantly higher than that in the normal gastric tissues adjacent to gastric cancer. Among the TNM stageⅠ, Ⅱ, Ⅲ of gastric cancer patients, the relative expression levels of miRNA-21 in the cancer tissues were 2.17 (1.48-2.90), 4.08 (2.30-4.86), 8.64 (5.82-18.20), respectively and the differences among these three stages were statistically significant (P<0.05). The relative expression level of the serum miRNA-21 in the gastric cancer patients was significantly higher than that in the nongastric cancer patients, which in the serums for stageⅠ, Ⅱ, and Ⅲpatients were 31.00 (24.60-37.15), 39.10 (28.90-39.80), 44.15 (38.95-56.68), respectively and the differences among three stages were statistically significant (P<0.05). The relative expression level of miRNA-21 in the serums and cancer tissues had a positive correlation (r=0.86, P<0.05). ConclusionMiRNA-21 appears to have a potential association with TNM stage of gastric cancer, which cautiously suggests that it might be a potential indicator for prediction of preoperative TNM stage of gastric cancer.
Lung cancer is the most common cancer worldwide. The outcome and management of lung cancer patients could be improved by early diagnosis and prognosis. MicroRNAs (miRNAs) have been implicated in signaling pathways regulating a variety of biological processes and play important roles in the development of carcinoma. Moreover, miRNAs can exist in the circulation in a remarkably stable form. All of these suggest miRNAs as new potentially clinical biomarkers for diagnosis and prognosis of lung cancer. In this review, we aim to discuss diagnostic and prognostic value and potential clinical utility of miRNAs in serum.
Objective To investigate the effects of the MKN-45 gastric cancer cell exosomes carrying microRNA-552 (miR-552) on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVEC). Methods ① The MKN-45 cells were divided into MKN-45 blank control group (no transfection), MKN-45 miR-552 inhibitor group [transfection of plasmid inhibiting mir-552 expression (mir-552 inhibitor plasmid)], and MKN-45 negative control group [transfection of negative control plasmid (empty plasmid)], the exosomes were extracted, purified, and identified. Western blotting was used to detect the protein expression of exosomal markers [CD63, CD9, and tumor susceptibility gene 101 (TSG101)]. ② The HUVEC cells were divided into HUVEC control group (added PBS), HUVEC-exosome group (co-cultured with exosomes of MKN-45 cell), HUVEC-negative control exosome group (co-cultured with exosomes of MKN-45 cell transfected with negative control plasmid), and HUVEC-miR-552 inhibitor exosome group (co-cultured with exosomes of MKN-45 cell transfected with miR-552 inhibitor plasmid), exosomes tracing experiment was used to detect whether exosomes entered HUVEC cells. Real-time fluorescent quantitative PCR method was used to detect the expression of miR-552, the MTT method was used to detect the proliferation of HUVEC cells, the Transwell chamber method was used to detect the migration of HUVEC cells, the angiogenesis test was used to detect the angiogenesis ability. Results This study successfully extracted exosomes from MKN-45 gastric cancer cells. Observed by transmission electron microscope, the exosomes were all round or elliptical, with a diameter of 100–150 nm, and the exosomal vesicle structure could be seen. Western blotting detection showed that the surface markers of exosomes (CD63, CD9, and TSG101 protein) were expressed in exosomes. The results of the tracing experiment showed that exosomes derived from MKN-45 cells were successfully internalized by HUVEC cells. After MKN-45 cells were transfected with miR-552 inhibitor plasmid, compared with the MKN-45 blank control group and MKN-45 negative control group, the relative expression level of miR-552 in the exosomes decreased (P<0.05). Compared with the HUVEC control group, the cell proliferation rate at 24, 48 and 74 h increased, as well as number of migration, tubule formation nodes, and relative expression level of miR-552 in the HUVEC-exosomes group increased (P<0.05). Compared with the HUVEC-negative control exosome group, the cell proliferation rate at 24, 48 and 74 h decreased, as well as the number of migration, tubule formation nodes, and relative expression level of miR-552 in the HUVEC-miR-552 inhibitor exosome group decreased (P<0.05). Conclusion The exosomes of gastric cancer cells carrying miR-552 can significantly promote the proliferation, migration, and angiogenesis of HUVEC cells.
Objective To investigate the effect of microRNA-584-5p (miR-584-5p) on the biological behavior (proliferation, migration and invasion) of breast cancer cells and its mechanism. Methods Human normal breast epithelial cells MCF10A and breast cancer cells MDA-MB-231, SK-BR-3 and MCF-7 were selected; take MCF-7 cells in logarithmic growth phase, transfect them with LipofectamineTM 2000 transfection kit, and divide them into seven groups: blank group (untransfected MCF-7 cells), mimic-negative control (mimic-NC) group (transfected mimic-NC), miR-584-5p mimic group (transfected miR-584-5p mimic), pcDNA group [transfected with overexpression of matrix metalloproteinase-14 (MMP-14) pcDNA3.1 plasmid negative control (pcDNA3.1)], MMP-14 group [transfected with overexpression of MMP-14 pcDNA3.1 plasmid (pcDNA3.1-MMP-14)], mimic-NC+MMP-14 group (co-transfected with mimic NC and pcDNA3.1-MMP-14), and miR-584-5p mimic+MMP-14 group (co-transfected with miR-584-5p mimic and pcDNA3.1-MMP-14). The mRNA expression levels of miR-584-5p in MCF10A, MDA-MB-231, SK-BR-3 and MCF-7 cells and the expression levels of miR-584-5p and MMP-14 mRNA of MCF-7 cell in each group were detected by fluorescence quantitative PCR. The protein expressions of MMP-14 of MCF-7 cell in each group were detected by Western blotting. The proliferation, migration and invasion of MCF-7 cell in each group were detected by cell counting kit - 8 (CCK-8), scratch test and Transwell test. The targeting relationship between miR-584-5p and MMP-14 was detected by double luciferase reporter gene assay. Results Compared with the human normal mammary epithelial cells MCF10A, the expression levels of miR-584-5p in breast cancer cells MDA-MB-231, SK-BR-3 and MCF-7 were decreased (P<0.05), and the expression level of miR-584-5p in MCF-7 cells was the lowest. Compared with the blank group and the mimic-NC group, the expression level of miR-584-5p of MCF-7 cells in the miR-584-5p mimic group was increased, and the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number were decreased or reduced (P<0.05). Compared with the blank group and the pcDNA group, the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number of MCF-7 cells in the MMP-14 group were increased (P<0.05). Compared with the MMP-14 group and the mimic-NC+MMP-14 group, the expression level of miR-584-5p of MCF-7 cells in the miR-584-5p mimic+MMP-14 group was increased, the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number were decreased or reduced (P<0.05). The expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number of MCF-7 cells in the miR-584-5p mimic+MMP-14 group were higher or morer than those in the miR-584-5p mimic group (P<0.05). The results of double luciferase reporter gene test showed that miR-584-5p could targeted action on the MMP-14 promoter region. Conclusions MiR-584-5p can targetable regulate the expression of MMP-14. Overexpression of miR-584-5p inhibits the proliferation, migration and invasion of breast cancer cells by down-regulating MMP-14.
Objective To review generation, distribution of microRNA-203 (miR-203) and it’s relation with tumors. Method Domestic and international literatures were collected to summarize the generation, distribution of miR-203 and it’s relation with tumors. Result Although the previous studies of miR-203 have shown an encouraging result, but only a small portion of miR-203 biological functions are identified, the regulatory mechanism of downstream target genes also has not been fully elucidated. Conclusion With deepening of research, miR-203 might play an active role in classification, categorizing, diagnosis, treatment, and prognosis of tumors.
Objective To review the regulation and mechanism of the microRNAs (miRNAs) in the bone and cartilage tissue. Methods Recent l iterature concerning the regulation and mechanism of the miRNAs in the bone and cartilage tissue was extensively reviewed, summarized, and analyzed. Results Recently miRNAs is a hot topic in the bone and cartilage tissue. More and more materials show its important regulatory role in osteogenesis and cartilage growth andregeneration, but the definite mechanisms have not been clear yet. Conclusion The study on miRNAs of bone and cartilage tissue can provide a new access to understanding the degenerative osteoarthritic diseases.