Intestinal immune suppression occurs in the early stage of SAP rats, which may be the main reason for bacterial and endotoxin translocation. L-arginine can improve the intestinal immunity and reduce bacterial and endotoxin translocation in SAP rats.

Purpose:The increase of both M2-type macrophages and Tregs is closely associated with the development of colorectal cancer. However, the mechanism of their interaction is still unclear. In this study, we investigated the correlation of M2-type macrophages with Tregs and the possible mechanisms between them. Methods: Using immunohistochemistry, we analysed Smad3 (a key protein in the TGF-β/ Smad signalling pathway) expression in colorectal cells, as well as infiltrating numbers of CD163 (a marker for M2-type macrophages), Foxp3 (a marker for Tregs) in 250 surgically resected colorectal cancer tissues, matched normal and paracancerous tissues. The relation of CD163 and Foxp3 was investigated in CRC with clinicopathological characteristics and preoperative tumour markers. Results: CD163, Foxp3 and Smad3 were upregulated in CRC tissues compared to matched normal and paracancerous tissues. Interestingly, CD163 and Foxp3 were significantly positively correlated in CRC, and both were significantly positively correlated with Smad3. Both CD163 and Foxp3 were upregulated with increasing tumour TNM staging, increasing number of lymph node metastases and increasing vascular invasion. Additionally, CD163 was upregulated with increasing depth of infiltration. The number of M2-type macrophages and the expression levels of preoperative CEA, CA19-9 and CA72-4 were significantly positively correlated. The number of Tregs was significantly positively correlated with the expression levels of preoperative CEA and CA19-9. Conclusion: M2-type macrophages may induce Tregs generation through activation of the TGF-β/Smad signalling pathway, which can promote the development of colorectal cancer.

Background Lymph node metastasis is a major prognostic sign of colorectal carcinoma and an important indicator for individualized treatment. M2 macrophages play a key role in carcinogenesis and tumor development by enhancing invasiveness and promoting lymph node metastasis. The purpose of this study was to investigate the effect of CD163-positive M2 macrophages on lymph node metastasis in colorectal carcinoma. Methods Postoperative lymph node tissues were obtained from 120 patients with colorectal carcinoma who underwent radical surgery in the First Affiliated Hospital of Jinzhou Medical University between December 2019 and May 2020. We detected the expression of the CD163 protein in lymph nodes using immunohistochemistry. Furthermore, the relationships between M2 macrophages identified by expression of CD163 and lymph node metastasis were analyzed using the independent sample t-test and Chi-square test. Results M2 macrophages were increased in metastatic lymph nodes and non-metastatic lymph nodes adjacent to the cancer. The M2 macrophage count was higher in patients with macro-metastases than in patients with micro-metastases. Conclusions The presence of M2 macrophages represents an important indicator for lymph node metastasis in colorectal carcinoma and may be a potential marker for its prediction. Thus, M2 macrophage localization might offer a new target for the comprehensive treatment of colorectal carcinoma.

BackgroundIncreased metastasis has been proved to be associated with a poor prognosis for hepatocellular carcinoma (HCC). There are higher-level expressions of integrin α6 in the tissues of HCC patients with a higher fatality rate. The aim of this study is to investigate the effect of short hairpin RNA (shRNA) silencing integrin α6 expression on the proliferation and metastasis in HCC cell lines.MethodsTwo human HCC cell lines, HepG2 and Bel-7402 were transfected with shRNA targeting human integrin α6. Protein and mRNA expression level were determined by western blot and real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to detect the transfected efficacy. The metastasis potential of HCC cells was evaluated by their proliferation, adhesion and invasion abilities. Cell proliferation was measured by MTT assay. Adhesion ability was measured by adhesion and spreading assays. The expression of matrix metalloproteinases (MMPs) was measured by qRT-PCR. The potential of invasion was measured by qRT-PCR and Transwell chamber assay. PI3K inhibitor LY294002 was used to explore the signal pathways of integrin α6 in HCC cells.ResultsWestern blot and qRT-PCR detection showed that over 75% of integrin α6 expression in HCC cells was through knockdown by shRNA. Proliferation, adhesion, spreading and invasion of HepG2 and Bel-7402 cells were dramatically decreased in cells transfected with shRNA compared to the control cells. P-ERK and p-AKT were reduced by shRNA targeting integrin α6 and PI3K inhibitor LY294002.ConclusionKnockdown integrin α6 can inhibit the proliferation and metastasis of HCC cells through PI3K/ARK and MAPK/ERK signal pathways by shRNA in vitro. Integrin α6 can mediate the metastasis potential, and can be used as a candidate target for therapy in HCC resulting in improved patients’ survival.

Background M2 macrophages and regulatory T cells (Tregs) can promote tumors and development by inhibiting the anti-tumor immune response. This study investigated the effect of CD163-positive M2 macrophages and Foxp3-positive Tregs in the progression of colorectal cancer and lymph node metastasis. It also investigated the correlation between M2 macrophages and Tregs. Methods Postoperative tissue specimens and clinical data were collected from 197 patients with colorectal cancer who underwent initial surgical treatment in The Second Ward of Colorectal Surgery of the First Affiliated Hospital of Jinzhou Medical University from March 2020 to December 2020. Immunohistochemical methods were used to detect the expression levels of CD163 protein-labeled M2 macrophages and Foxp3 protein-labeled Tregs in colorectal cancer tissues, matched paracancer tissues, and lymph node tissues. The correlation between CD163 and Foxp3 in cancer tissues and lymph node tissues were analyzed, as well as the relationship between clinicopathological characteristics and preoperative tumor markers. Results M2 macrophages and Tregs were importantly positively correlated in cancer and lymph node tissues, which significantly increased in cancer and metastatic lymph node tissues. Interestingly, M2 macrophages in non-metastatic lymph nodes also increased significantly in patients with metastatic lymph nodes. In addition, both CD163 and Foxp3 were upregulated with increasing tumor node metastasis stage, depth of infiltration, and lymphatic metastasis; and both were positively correlated with carcinoembryonic antigen. Conclusion CD163 may be a good predictor of pre-metastatic status of colorectal cancer lymph nodes. carcinoembryonic antigen affects the distribution of M2 macrophages and Tregs in colorectal cancer. There is a certain correlation between the two types of cells. It is possible that M2 macrophages, together with suppressor Tregs cells, promote an immunosuppressive environment.