Combined therapy with early initiation of infliximab following drainage of perianal fistulising Crohn's disease: a retrospective cohort study.

BACKGROUND: Recent studies have confirmed that combined surgery and anti-TNF therapy could improve outcomes in patients with perianal fistulising Crohn's disease (PFCD). However, the optimal timing for infliximab infusion after surgical intervention is uncertain. We aimed to determine the long-term efficacy of early initiation of infliximab following surgery among PFCD patients. METHODS: We performed a retrospective cohort study of PFCD patients who received combined infliximab and surgical treatment between 2010 and 2018 at a tertiary referral hospital. Patients were grouped according to the time interval between surgery and infliximab infusion, with < 6 weeks into early infliximab induction group and > 6 weeks into delayed infliximab induction group. The primary outcome was to compare surgical re-intervention between early and delayed infliximab induction groups. The secondary outcomes were fistula healing and predictors associated with these outcomes of early infliximab induction approach. RESULTS: One hundred and seventeen patients were included (73 in early infliximab induction, 44 in delayed infliximab induction). The median interval between surgery and infliximab initiation was 9.0 (IQR 5.5-17.0) days in early infliximab induction group and 188.0 (IQR 102.25-455.75) days in delayed infliximab induction group. After followed-up for a median of 36 months, 61.6% of patients in early infliximab induction group and 65.9% in delayed infliximab induction group attained fistula healing (p = 0.643). The cumulative re-intervention rate was 23%, 32%, 34% in early infliximab induction group and 16%, 25%, 25% in delayed infliximab induction group, at 1, 2, and 3 years respectively (p = 0.235). Presence of abscess at baseline (HR = 5.283; 95% CI, 1.61-17.335; p = 0.006) and infliximab maintenance therapy > 3 infusions (HR = 3.691; 95% CI, 1.233-11.051; p = 0.02) were associated with re-intervention in early infliximab induction group. Presence of abscess at baseline also negatively influenced fistula healing (HR = 3.429, 95% CI, 1.216-9.668; p = 0.02). CONCLUSION: Although no clear benefit was shown compared with delayed infliximab induction group, early initiation of infliximab after surgery could achieve promising results for PFCD patients. Before infliximab infusion, durable drainage is required for patients with concomitant abscess or prolonged infliximab maintenance therapy.

Metabolic engineering of Escherichia coli W3110 for the production of L-methionine.

In this study, we constructed an L-methionine-producing recombinant strain from wild-type Escherichia coli W3110 by metabolic engineering. To enhance the carbon flux to methionine and derepression met regulon, thrBC, lysA, and metJ were deleted in turn. Methionine biosynthesis obstacles were overcome by overexpression of metA Fbr (Fbr, Feedback resistance), metB, and malY under control of promoter pN25. Recombinant strain growth and methionine production were further improved by attenuation of metK gene expression through replacing native promoter by metK84p. Blocking the threonine pathway by deletion of thrBC or thrC was compared. Deletion of thrC showed faster growth rate and higher methionine production. Finally, metE, metF, and metH were overexpressed to enhance methylation efficiency. Compared with the original strain E. coli W3110, the finally obtained Me05 (pETMAFbr-B-Y/pKKmetH) improved methionine production from 0 to 0.65 and 5.62 g/L in a flask and a 15-L fermenter, respectively.

Molecular screening and clinicopathologic characteristics of Lynch-like syndrome in a Chinese colorectal cancer cohort.

Colorectal cancers (CRC) with microsatellite instability (MSI) or mismatch repair-deficiency (dMMR), but without detectable MMR germline mutations are termed Lynch-like syndrome (LLS). We assess the clinicopathologic and molecular characteristics of LLS tumors and the proportion in LLS, which remain poorly investigated in China. We enrolled 404 CRC patients with surgery in our institution from 2014 to 2018. LLS tumors were detected by a molecular stratification based on MMR protein expression, MLH1 methylation and MMR gene mutation. LLS tumors were profiled for germline mutations in 425 cancer-relevant genes. Among 42 MMR-deficient tumors, 7 (16.7%) were attributable to MLH1 methylation and 7 (16.7%) to germline mutations, leaving 28 LLS cases (66.6%). LLS tumors were diagnosed at a mean age of 60.7 years, had an almost equivalent ratio among rectum, left colon and right colon, and had high rates of lymph node metastases (50%, 4/28 N2). Most MMR gene mutations (88.2%, 15/17) in LLS tumors were variants of unknown significance (VUS). Two novel frameshift mutations were detected in ATM and ARID1A, which are emerging as candidate responsible genes for LLS. In this study, 28 (66.6%) MMRd tumors were classified as LLS, which were significantly higher than reports of western countries. LLS tumors were more likely to carry lymph node metastases. However, it's hard to differentiated LLS tumors from LS through family history, tumor location, histological type of tumors, immunohistochemistry (IHC) for MMR proteins and MSI analysis.

Total flavone of Abelmoschus manihot suppresses epithelial-mesenchymal transition via interfering transforming growth factor-ß1 signaling in Crohn's disease intestinal fibrosis.

AIM: To explore the role and mechanism of total flavone of Abelmoschus manihot (TFA) on epithelial-mesenchymal transition (EMT) progress of Crohn's disease (CD) intestinal fibrosis. METHODS: First, CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial (IEC-6) cells and select the optimal concentrations of TFA for our further studies. Then cell morphology, wound healing and transwell assays were performed to examine the effect of TFA on morphology, migration and invasion of IEC-6 cells treated with TGF-ß1. In addition, immunofluorescence, real-time PCR analysis (qRT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress. Moreover, western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways. Further, the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by qRT-PCR, western blotting, morphology, wound healing and transwell assays. RESULTS: In this study, TFA promoted transforming growth factor-ß1 (TGF-ß1)-induced (IEC-6) morphological change, migration and invasion, and increased the expression of epithelial markers and reduced the levels of mesenchymal markers, along with the inactivation of Smad and MAPK signaling pathways. Moreover, we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-ß1-induced EMT in IEC-6 cells. Importantly, co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-ß1-induced EMT in IEC-6 cells than either one of them. CONCLUSION: These findings could provide new insight into the molecular mechanisms of TFA on TGF-ß1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.

Methylation-regulated miR-149 modulates chemoresistance by targeting GlcNAc N-deacetylase/N-sulfotransferase-1 in human breast cancer.

Dysregulation of microRNA is strongly implicated in the chemoresistance of cancer. In this study, we found that miR-149 was downregulated and involved in chemoresistance in adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM). Downregulation of miR-149 was related to hypermethylation of its 5'-UTR; this methylation also affected the expression of the glypican 1 gene, which is both the host and the target gene of miR-149. Furthermore, we found that miR-149 modulated chemoresistance through targeting the expression of GlcNAc N-deacetylase/N-sulfotransferase-1 (NDST1). With downregulated miR-149, NDST1 expression was increased in chemoresistant MCF-7/ADM cells versus control MCF-7 wild-type cells. The increased NDST1 then activated a heparan sulfate-related pathway involving activation of heparanase. Finally, expression of miR-149 and NDST1 was confirmed in clinical chemoresistant samples of breast cancers receiving anthracycline/taxane-based chemotherapies. The high expression of NDST1 was also an unfavorable predictor for distant relapse-free survival in Her2 and basal breast cancers. Taken together, our findings demonstrate that miR-149 is regulated by methylation, and is a modulator of cancer chemoresistance by targeting NDST1.