Targeted delivery of irinotecan to colon cancer cells using epidermal growth factor receptor-conjugated liposomes.

BACKGROUND: CPT-11 (irinotecan) is one of the most efficient agents used for colorectal cancer chemotherapy. However, as for many other chemotherapeutic drugs, how to minimize the side effects of CPT-11 still needs to be thoroughly described. OBJECTIVES: This study aimed to develop the CPT-11-loaded DSPE-PEG 2000 targeting EGFR liposomal delivery system and characterize its targeting specificity and therapeutic effect on colorectal cancer (CRC) cells in vitro and in vivo. RESULTS: The synthesized liposome exhibited spherical shapes (84.6 ± 1.2 nm to 150.4 nm ± 0.8 nm of estimated average sizes), good stability, sustained release, and enough drug loading (55.19%). For in vitro experiments, SW620 cells treated with CPT-11-loaded DSPE-PEG2000 targeting EGFR liposome showed lower survival extended level of intracellular ROS production. In addition, it generated an enhanced apoptotic cell rate by upregulating the protein expression of both cleaved-caspase-3 and cleaved-caspase-9 compared with those of SW620 cells treated with free CPT-11. Importantly, the xenograft model showed that both the non-target and EGFR-targeted liposomes significantly inhibited tumor growth compared to free CPT-11. CONCLUSIONS: Compared with the non-target CPT-11-loaded DSPE-PEG2000 liposome, CPT-11-loaded DSPE-PEG2000 targeting EGFR liposome treatment showed much better antitumor activity in vitro in vivo. Thus, our findings provide new assets and expectations for CRC targeting therapy.

FOXQ1-mediated SIRT1 upregulation enhances stemness and radio-resistance of colorectal cancer cells and restores intestinal microbiota function by promoting ß-catenin nuclear translocation.

BACKGROUND: Resistance of colorectal cancer (CRC) cells to radiotherapy considerably contributes to poor clinical outcomes of CRC patients. Microarray profiling in this study revealed the differentially expressed forkhead box Q1 (FOXQ1) in CRC, and thus we aimed to illustrate the role of FOXQ1 in CRC by modulating stemness and radio-resistance of CRC cells. METHODS: CRC and adjacent normal tissues were collected from CRC patients, and the correlation between FOXQ1 expression and CRC prognosis was analyzed. Subsequently, we determined the expression of FOXQ1, sirtuin 1 (SIRT1) and ß-catenin in CRC tissues and cell lines. The binding affinity between FOXQ1 and SIRT1 and that between SIRT1 and ß-catenin were validated with luciferase reporter gene, Co-IP and ChIP assays. Following a metagenomics analysis of CRC intestinal microbiota, the effects of the FOXQ1/SIRT1/ß-catenin axis on CRC stem cell phenotypes and radio-resistance was evaluated in vitro and in vivo through manipulation of gene expression. Besides, mouse feces were collected to examine changes in intestinal microbiota. RESULTS: FOXQ1 was highly expressed in CRC tissues and cells and positively correlated with poor prognosis of CRC patients. FOXQ1 overexpression contributed to resistance of CRC cells to radiation. Knockdown of FOXQ1 inhibited the stemness of CRC cells and reversed their radio-resistance. FOXQ1 enhanced the transcriptional expression of SIRT1, and SIRT1 enhanced the expression and nuclear translocation of ß-catenin. Knockdown of FOXQ1 repressed SIRT1 expression, thus reducing the stemness and radio-resistance of CRC cells. Moreover, FOXQ1 knockdown suppressed CRC xenograft formation in xenograft-bearing nude mice through inhibiting SIRT1 and ß-catenin to reduce the content of pathological bacteria that were up-regulated in CRC. CONCLUSION: FOXQ1-mediated SIRT1 upregulation augments expression and nuclear translocation of ß-catenin and benefits CRC-related intestinal pathological bacterial, thereby enhancing the stemness and radio-resistance of CRC cells.

Short-Chain Fatty Acid Decreases the Expression of CEBPB to Inhibit miR-145-Mediated DUSP6 and Thus Further Suppresses Intestinal Inflammation.

Intestinal inflammation is a common disease which can further lead to inflammatory bowel disease and even intestinal cancer. The increasing focus has come to the role of short-chain fatty acid (SCFA) in various bowel diseases. Hence, this study was designed to explore the specific role of SCFA in intestinal inflammation. In vivo and in vitro models of intestinal inflammation were constructed by lipopolysaccharide (LPS) injection in mice and LPS treatment on intestinal epithelial cells. A possible regulatory mechanism involving SCFA, CCAAT enhancer-binding protein beta (CEBPB), microRNA-145 (miR-145), and dual-specificity phosphatase 6 (DUSP6) in intestinal inflammation was verified by ChIP assay and dual-luciferase reporter gene assay. To evaluate the effects of SCFA on LPS-treated intestinal epithelial cells, the expression of relevant genes and inflammatory factors (IL-6, TNF-α, and IL-1ß) were determined. Last, the role of SCFA in vivo was explored through the scoring of disease activity index (DAI) and observation of colonic histology of LPS-treated mice. SCFA decreased the CEBPB expression in mouse colon tissues and small intestine epithelial cells induced by LPS. Furthermore, CEBPB could bind to the miR-145 promoter to inhibit its expression, thereby promoting the expression of DUSP6. In addition, SCFA improved the DAI, colonic histology, and the expression of serum inflammatory factors in LPS-treated mice and cells, noting that SCFA alleviated intestinal inflammation in vitro and in vivo. To sum up, SCFA inhibited DUSP6 by upregulating miR-145 through CEBPB repression and thus prevented the development of intestinal inflammation.

Efficacy of faecal microbiota transplantation on ulcerative colitis and its effect on gastrointestinal motility and immune function.

OBJECTIVE: To investigate the efficacy of faecal microbiota transplantation (FMT) in the treatment of ulcerative colitis (UC) and its effect on gastrointestinal motility (GM) and immune function. METHODS: A retrospective cohort study was conducted on 47 UC patients. The patients were divided into an observation group (n=17, treated with FMT) and a control group (n=30, treated with conventional treatment) according to the treatment regimen. In the observation group, FMT was used to treat colonic lesions by transplanting colonic bacteria fluid from healthy people. Clinical efficacy, immune function, level of inflammatory factors and gastrointestinal function of the two groups were observed before and after treatment. RESULTS: The total response rates of observation group was 94.12%, which was higher than that of control group (70.00%; P<0.05). After treatment, the contents of CD3+, CD4+ T cells and CD4+/CD8+ ratio were increased, while the content of CD8+ T cells was decreased in both groups compared with those before treatment (all P<0.05); and the contents of CD3+, CD4+ T cells and CD4+/CD8+ ratio in the observation group were higher than those in the control group, while CD8+ T cells showed an opposite trend (P<0.05). The levels of immunoglobulin A, immunoglobulin G and immunoglobulin M as well as interleukin-6, C-reactive protein, tumor necrosis factor-α and motilin were lower than those before treatment in both groups (all P<0.05), and the decreases in the observation group were more significant than those in the control group (all P<0.001). After treatment, cholecystokinin and vasoactive peptide were higher than those before treatment in both groups (all P<0.05), and the increased degree in the observation group was more obvious than that in the control group (all P<0.001). CONCLUSION: FMT has significant clinical efficacy in the treatment of UC, which may be related to the improvement of immune function, alleviation of inflammatory response and promotion of GM recovery.

Three-dimensional co-culture of hepatic progenitor cells and mesenchymal stem cells in vitro and in vivo.

INTRODUCTION: Here we co-cultured hepatic progenitor cells (HPCs) and mesenchymal stem cells (MSCs) to investigate whether the co-culture environments could increase hepatocytes form. METHODS: Three-dimensional (3D) co-culture model of HPCs and MSCs was developed and morphological features of cells were continuously observed. Hepatocyte specific markers Pou5f1/Oct4, AFP, CK-18 and Alb were analyzed to confirm the differentiation of HPCs. The mRNA expression of CK-18 and Alb was analyzed by RT-PCR to investigate the influence of co-culture model to the terminal differentiation process of mature hepatocytes. The functional properties of hepatocyte-like cells were detected by continuously monitoring the albumin secretion using Gaussia luciferase assays. Scaffolds with HPCs and MSCs were implanted into nude mouse subcutaneously to set up the in vivo co-culture model. RESULTS: Although two groups formed smooth spheroids and high expressed of CK-18 and Alb, hybrid spheroids had more regular structures and higher cell density. CK-18 and Alb mRNA were at a relatively higher expression level in co-culture system during the whole cultivation time (P < 0.05). Albumin secretion rates in the hybrid spheroids had been consistently higher than that in the mono-culture spheroids (P < 0.05). In vivo, the hepatocyte-like cells were consistent with the morphological features of mature hepatocytes and more well-differentiated hepatocyte-like cells were observed in the co-culture group. CONCLUSIONS: HPCs and MSCs co-culture system is an efficient way to form well-differentiated hepatocyte-like cells, hence, may be helpful to the cell therapy of hepatic tissues and alleviate the problem of hepatocytes shortage.

Body position adjustment may facilitate capsule endoscopic real-time examination in patients with a large amount of food retention in the stomach.

A patient with acute obscure gastrointestinal bleeding was found to have a large amount of food retention in the stomach after fasting for >12 hours. We tried to adjust the patient's body position to facilitate capsule endoscopic examination. The patient laid on the bed on his right side, which is the position required for a normal procedure, and then his hip was raised while his upper body was lowered gradually until the pylorus appeared at the center of the screen of the real-time monitor. It took 15 minutes of body position adjustment to make the pylorus appear at the center of the monitor and another 5 minutes for the capsule endoscope to enter the duodenum. The lesion was ultimately found at the terminal small intestine.