ObjectiveTo explore the influence of miRNA-155/PU.1 signaling pathway blockade on bone marrow-derived dendritic cells (DCs) maturation and immune function of rat small intestinal transplantation. MethodsThe DCs were induced by adherent culture.The critical transcription factor gene PU.1 was designed and PU.1 siRNA was synthe-sized.The DCs were transfected by liposome transfection and a pair of PU.1 siRNA was screened according to the high silencing efficiency.The expressions of DCs surface markers CD80, CD86, and MHC-Ⅱamong three groups (PU.1 silent group, negative control group, and control group) were analyzed by flow cytometry.The IL-10 and IL-12p70 secretion levels in the supernatant were tested by ELISA method.The allogeneic T lymphocyte proliferation was tested by mixed lymphocyte reaction.The transfected cells were intravenously injected into the recipient rat on day 7 before intestinal transplantation.The survival conditions as well as pathological changes were observed in each group recipients. Results①The surface molecules CD80, CD86, and MHC-Ⅱin the PU.1 silent group were (27.0±5.6)%, (23.6±4.8)%, and (36.8±6.8)%, respectively; versus (74.0±9.4)%, (76.5±8.7)%, and (87.8±11.3)% in the negative control group, respectively, which were significantly lower in former and showing an in creased trend (P < 0.05).②Compared with the negative control group, IL-10 secretion level was significantly increased (P < 0.05), IL-12p70 secretion level significantly decreased (P < 0.05) in the PU.1 silent group.③The proliferation of T lymphocytes in the PU.1 silent group was significantly lower than that in the negative control group (P < 0.05).④When the transfected DCs were injected into the intestinal transplantation rats on day 7 before operation, the survival time was (14.3±3.3) d, (7.8±1.5) d, and (8.0±2.5) d in the PU.1 silent group, negative control group, and control group, respectively, which in the PU.1 silent group were significantly longer than that in the other two groups (P < 0.05), and the graft pathology showed that there were mild intestinal tissue damage, lymphocyte infiltration or villus edema in the PU.1 silent group. ConclusionmiRNA-155/PU.1 signaling pathway blockade could reduce DCs maturation and induce receptor-specific immune tolerance, which are proved both in vivo and in vitro.
ObjectiveTo investigate the expression of miRNA-1 in denervated skeletal muscle at different periods, and to explore effects of passive movement on the expression of miRNA-1 and differentiation of myoblasts in denervation-induced skeletal muscle atrophy in rats. MethodsTwenty-seven Sprague Dawley rats, weighing (200±10) g, were randomly divided into sham-operated group (group A, n=3), denervated group (group B, n=12), and passive movement group (group C, n=12). After the right sciatic nerve was exposed and dissociated, the sciatic nerve of 1 cm in length was removed in groups B and C; resection was not performed in group A. At 1 day after operation, passive flexion and extension movement was performed on the right hind limb in group C. At 6 hours in group A and at 3, 7, 14, and 28 days in groups B and C, 3 rats were sacrificed to measure the wet weight ratio of gastrocnemius muscle, to observe the diameter of the gastrocnemius muscle cell and evaluate the muscle atrophy by HE staining; RT-PCR was used to detect the mRNA expression of miRNA-1 and myocyte differentiation factor (MyoD), and immunohistochemistry to determine the protein expression of MyoD. ResultsAtrophy in various degrees was observed in denervated gastrocnemius muscle of groups B and C. The muscle fiber arranged in disorder and the diameter of the muscle cells decreased gradually with the time, without normal structure and morphology. The wet weight ratio and the cell diameter of the gastrocnemius in groups B and C were significantly less than those in group A (P<0.05); the wet weight ratio at 7, 14, 28 days and the cell diameter at 7, 14 days of group B were significantly greater than those of group A (P<0.05). The expressions of miRNA-1 and MyoD mRNA gradually increased with time in groups B and C, but were significantly less than those of group A at each time point (P<0.05). At 7, 14, and 28 days after operation, the expressions of miRNA-1 and MyoD mRNA in group C were significantly higher than those in group B (P<0.05). Immunohistochemical staining showed positive expression of MyoD in groups A, B, and C at each time point, but higher expression was observed in groups B and C than group A; the expression increased with time in groups B and C, and it was significantly higher in group C than group B. The correlation analysis results showed that the overall change trend of miRNA-1 and MyoD had no relation with the gastrocnemius wet weight ratio at 3 and 7 days (P>0.05), and had positive correlation at 14 and 28 days (P<0.05); positive correlation was found between the relative expression of MyoD and miRNA-1 mRNA (P<0.05). ConclusionPassive movement can prevent amyotrophy by increasing the expression of miRNA-1 and promoting the differentiation of myoblasts.
Colorectal cancer is one of the most common malignant diseases that threatens human being's health. With researches on microRNAs (miRNAs) getting deeper and wider, more evidences revealed that a great many of miRNAs have been involved in the development of colorectal cancer and have the potential to become the biomarker for early diagnosis, prediction of prognosis and recurrence of colorectal cancer. MiRNA-143/miRNA-145 are significantly reduced in several cancers, including colorectal cancer, showing an antitumorigenic activity. In the present article, we make a brief review on the advances in the researches on miRNA-143/miRNA-145 and colorectal cancer to provide guidance for further explorations of the mechanism and target therapy of this disease.
ObjectiveTo explore expression, clinical and biological significance of plasma miRNA-196a from patients with advanced gastric cancer.MethodsReal time quantitative RT-PCR (qRT-PCR) method was used to detect the miRNA-196a levels in tissues and plasma from 75 gastric cancer patients and 35 benign gastric lesions controls. Then clinic pathological correlations of plasma miRNA-196a in 75 gastric cancer patients were analyzed. Twenty-five gastric cancer patients were randomized selected from 75 patients, to compare plasma miRNA-196a levels between preoperation and postoperation. Meanwhile, the effect of miRNA-196a on the invasion ability of gastric cancer MGC-803 cell line was observed in vitro.ResultsThe levels of miRNA-196a in both plasma and tissues from 75 gastric cancer patients were significantly increased compared with 35 benign gastric lesions controls (P<0.000 1). Clinic pathological data of 75 gastric cancer patients showed that the expressions of miRNA-196a were significantly up-regulated in gastric cancer patients with serosal invasion (P<0.001), lymph node metastasis (P=0.004), distant metastasis (P<0.001) and late clinical stage (P<0.001). The expression of miRNA-196a in peripheral plasma of patients with gastric cancer was significantly down regulated after operation (P<0.000 1). In vitro, overexpression of miRNA-196a significantly increased the invasion ability of MGC-803 cells (P<0.05), whereas knockdown of endogenous miRNA-196a significantly inhibited the invasion ability of MGC-803 cells (P<0.05).ConclusionsThe expression of miRNA-196a is up-regulated not only in peripheral plasma of patients with gastric cancer, but also with the progression of gastric cancer (serosal invasion, lymph node metastasis and distant metastasis). The up-regulation of miRNA-196a expression in peripheral plasma is mainly due to the release of primary tumor tissue. miRNA-196a is expected to be a prognostic marker and a potential therapeutic target for advanced gastric cancer.