N6-methyladenosine-modified circular RNA QSOX1 promotes colorectal cancer resistance to anti-CTLA-4 therapy through induction of intratumoral regulatory T cells.

BACKGROUND: Colorectal cancer (CRC) is the 3rd most common cancer worldwide. CircRNAs are promising novel biomarkers for CRC. T regulatory (Treg) cells express the immune checkpoint receptor of cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and promote tumor immunological tolerance. We therefore investigate the biological functions and mechanisms of circQSOX1 in CRC tumorigenesis; involvement of circQSOX1 in promoting Treg cell-mediated CRC immune escape in anti-CTLA-4 therapy. METHODS: Bioinformatics analyses were performed for circQSOX1expressions, specific binding sites, and N6-methyladenosine (m6A) motifs of circQSOX1, thatwere further validated with a series of experiments. Functions of circQSOX1 in promoting CRC development, Treg cells-based immune escape, and anti-CTLA-4 therapy response were investigated both in vitro and in vivo. RESULTS: High circQSOX1 expression was associated with carcinogenesis and poor clinical outcome of CRC patients. METTL3-mediated RNA m6A modification on circQSOX1 could be read by IGF2BP2 in CRC cells. CircQSOX1 promoted CRC development by regulating miR-326/miR-330-5p/PGAM1 axis. CircQSOX1 regulated glycolysis and promoted immune escape of CRC cells, and inhibits anti-CTLA-4 therapy response in CRC patients. CONCLUSION: m6A-modified circQSOX1 facilitated CRC tumorigenesis by sponging miR-326 and miR-330-5p to promotes PGAM1 expression, which further promoted CRC immune escape by activating glycolysis and inactivating the anti-CTLA-4 therapy response of CRC. Combined treatment with sh-circQSOX1 and anti-CTLA-4 could be a strategy to overcome Treg cell-mediated CRC immune therapy resistance.

PIK3CA mutations-mediated downregulation of circLHFPL2 inhibits colorectal cancer progression via upregulating PTEN.

BACKGROUND: PIK3CA mutation and PTEN suppression lead to tumorigenesis and drug resistance in colorectal cancer (CRC). There is no research on the role of circular RNAs (circRNAs) in regulating PIK3CA mutation and MEK inhibitor resistance in CRC. METHODS: The expression of circLHFPL2 in PIK3CA-mutant and wild-type cells and tissues was quantified by RNA-sequencing and qRT-PCR. CCK-8 assay and colony formation assay were used to evaluate cell viability. Annexin V/PI staining was implemented to assess cell apoptosis. Luciferase assay, biotin-coupled microRNA capture, and RIP assay were used to validate the interaction among potential targets. Western blotting and qRT-PCR assays were used to evaluate the expression of involved targets. Xenograft tumor in a nude mouse model was used to explore the role of circRNAs in vivo. RESULTS: RNA sequencing defined downregulated expression of circLHFPL2 in both PIK3CAH1047R (HCT116) and PIK3CAE545K (DLD1) cells. CircLHFPL2 was also downregulated in PIK3CA-mutant CRC primary cells and tissues, which was correlated with poor prognosis. CircLHFPL2 was mainly localized in the cytoplasm and its downregulation was attributed to the PI3K/AKT signaling pathway activated by phosphorylating Foxo3a. CircLHFPL2 inhibited PI3KCA-Mut CRC progression both in vitro and in vivo. Furthermore, our work indicated that circLHFPL2 acts as a ceRNA to sponge miR-556-5p and miR-1322 in CRC cells and in turn modulate the expression of PTEN. Importantly, circLHFPL2 was able to overcome PIK3CA-mediated MEK inhibitor resistance in CRC cells. CONCLUSIONS: Downregulation of circLHFPL2 sustains the activation of the PI3K/AKT signaling pathway via a positive feedback loop in PIK3CA-mutant CRC. In addition, downregulation of circLHFPL2 leads to MEK inhibitor resistance in CRC. Therefore, targeting circLHFPL2 could be an effective approach for the treatment of CRC patients harboring oncogenic PIK3CA mutations.

Colistin sulfate for decontamination of preservation fluid in kidney transplantation to decrease the incidence of donor-derived infections caused by multidrug-resistant Gram-negative bacteria.

BACKGROUND: Preservation fluid (PF) contamination, especially by multidrug-resistant (MDR) Gram-negative bacteria (GNB), poses a high risk of donor-derived infection (DDI) and severe clinical outcomes. We sought to determine whether the use of colistin sulfate to decontaminate PF in kidney transplantation can decrease the incidence of probable DDI (p-DDI) caused by MDR GNB. METHODS: In a retrospective study of 916 recipients who received deceased donation, 864 PF samples were collected and cultured, and microbiological contaminants were recorded with the recipients' clinical data and outcomes. From March 2016 to May 2019, 624 samples were decontaminated with ceftizoxime, and from June 2019 to March 2021, 240 samples were decontaminated with colistin sulfate. Between-group comparisons were performed to assess the ability of the two decontamination regimens to decrease the incidence of p-DDI, especially MDR GNB-related infection. RESULTS: The overall PF contamination rate was 54.51% (471/864), and 80 samples were positive for MDR GNB contamination. All p-DDIs occurred in the ceftizoxime group (p < 0.001), and 67.65% of p-DDIs were MDR GNB-related. In the ceftizoxime group, 23 of 61 cases of MDR GNB contamination led to related p-DDIs, while none occurred in the colistin sulfate group (p = 0.002). Among the 23 patients with p-DDIs, 5 died due to severe infection, and 2 experienced graft loss. CONCLUSIONS: The goal of decontamination should be to decrease the risk of MDR GNB-related p-DDI, and colistin sulfate could be an effective and feasible option.

Multiregion single cell analysis reveals a novel subtype of cancer-associated fibroblasts located in the hypoxic tumor microenvironment in colorectal cancer.

BACKGROUND: The tumor microenvironment (TME) plays a critical role in shaping tumor progression and determining the outcome of the therapeutic response. In this study, we aimed to generate a comprehensive cellular landscape of the colorectal cancer (CRC) TME. METHODS: We generated a comprehensive single-cell atlas by collecting CRC cases that have been uploaded to the online database and conducting an in-depth secondary analysis. We then carried out spatial transcriptomic sequencing and multiple immunohistochemical analyses to verify the results of the single-cell analysis. Moreover, we applied our findings to the TCGA database and used tissue microarray (TMA) on CRC tissue specimens to validate clinical prognosis. FINDINGS: We re-analyzed the transcriptomes of 23785 cells, revealing a pattern of cell heterogeneity in the tumor region, leading-edge region, and non-tumor region. A subtype of COL11A1+INHBA+ tumor-resident cancer-associated fibroblasts (CAFs) was identified, and marker genes, transcription factors, and tissue-specific expression differences were noted and suggested to have potential roles in promoting cancer. We further confirmed that COL11A1+INHBA+ tumor-resident CAFs are mainly located in the hypoxic TME and we propose that they interact with CD44+ CRC cells via INHBA. Elevation of INHBA in CRC is associated with a poor prognosis. INTERPRETATION: Our results demonstrated a single cell landscape of CRC in different regions and identified in hypoxic TME a special subtype of CAFs producing INHBA, which promotes CRC development and correlates with poor prognosis. This special subtype of CAFs is a candidate target for translational research.

Predicting the risk of distant metastasis in patients with locally advanced rectal cancer using model based on pre-treatment T2WI-based radiomic features plus postoperative pathological stage.

Objective: To assess the prognostic value of a model based on pre-treatment T2WI-based radiomic features and postoperative pathological staging in patients with locally advanced rectal cancer who have undergone neoadjuvant chemoradiotherapy. Methods: Radiomic features were derived from T2WI, and a radiomic signature (RS) was established and validated for the prediction of distant metastases (DM). Subsequently, we designed and validated a nomogram model that combined the radiomic signature and postoperative pathological staging for enhanced DM prediction. Performance measures such as the concordance index (C-index) and area under the curve (AUC) were computed to assess the predictive accuracy of the models. Results: A total of 260 patients participated in this study, of whom 197 (75.8%) were male, and the mean age was 57.2 years with a standard deviation of 11.2 years. 15 radiomic features were selected to define the radiomic signature. Patients with a high-risk radiomic signature demonstrated significantly shorter distant metastasis-free survival (DMFS) in both the development and validation cohorts. A nomogram, incorporating the radiomic signature, pathological T stage, and N stage, achieved an area under the curve (AUC) value of 0.72 (95% CI, 0.60-0.83) in the development cohort and 0.83 (95% CI, 0.73-0.92) in the validation cohort. Conclusion: A radiomic signature derived from T2WI-based radiomic features can effectively distinguish patients with varying risks of DM. Furthermore, a nomogram integrating the radiomic signature and postoperative pathological stage proves to be a robust predictor of DMFS.

Changing trends, clinicopathological characteristics, surgical treatment patterns, and prognosis of schistosomiasis-associated versus non-schistosomiasis-associated colorectal cancer: a large retrospective cohort study of 31 153 cases in Shanghai, China (2001-2021).

BACKGROUND: With the elimination of schistosomiasis in China, its role in the pathogenesis of colorectal cancer (CRC) has decreased. However, the trends, clinicopathological features, surgical treatment patterns, and prognosis of schistosomiasis-associated CRC (SACRC) versus non-schistosomiasis-associated CRC (NSACRC) in China remain unclear. MATERIALS AND METHODS: The percentage trend of SACRC in CRC patients in China was analyzed using data retrieved from the Pathology Registry of Changhai Hospital (2001-2021). Clinicopathological characteristics, surgical treatment patterns, and prognosis-related parameters were compared between the two groups. Multivariate Cox regression analyses were performed for disease-free survival (DFS) and overall survival (OS). RESULTS: A total of 31 153 CRC cases were included, with 823 (2.6%) cases of SACRC and 30 330 (97.4%) cases of NSACRC. The average percentage of SACRC cases has decreased continuously from 3.8 to 1.7% (from 2001 to 2021). Compared with the NSACRC group, the SACRC group had more men, older age at diagnosis, lower BMI, fewer symptoms; higher rates of rectal cancer, comorbidities, KRAS mutation, multiple primary CRC and concomitant polyps; less lymph node metastasis, distant metastasis, vascular invasion, and tumor budding; less preoperative radiotherapy and preoperative chemotherapy; and more positive resection margins and postoperative targeted therapy. There were no significant differences between the two groups regarding laparoscopic surgery, palliative resection, extended radical resection, or ostomy. Moreover, the SACRC group had adverse DFS and similar OS compared with the NSACRC group. In multivariate analyses, schistosomiasis was not an independent predictor of DFS or OS. CONCLUSION: The percentage of SACRC in CRC (2.6%) in our hospital was very low, and it decreased continuously over the last two decades, indicating that schistosomiasis is no longer an important risk factor for CRC in Shanghai, China. Patients with SACRC have distinct clinicopathological, molecular, and treatment-related features and survival rates similar to those with NSACRC.

Preoperative nomogram to predict survival following colorectal cancer liver metastasis simultaneous resection.

BACKGROUND: Simultaneous resection for patients with synchronous colorectal cancer liver metastases (CRLM) remains an optimal option for the sake of curability. However, few studies so far focus on outcome of this subgroup of patients (who receive simultaneous resection for CRLM). Substantial heterogeneity exists among such patients and more precise categorization is needed preoperatively to identify those who may benefit more from surgery. In this study, we formulated this internally validated scoring system as an option. METHODS: Clinicopathological and follow-up data of 234 eligible CRLM patients undergoing simultaneous resection from January 2010 to March 2019 in our center were included for analysis. Patients were randomized to either a training or validation cohort. We performed multivariable Cox regression analysis to determine preoperative factors with prognostic significance using data in training cohort, and a nomogram scoring system was thus established. Time-dependent receiver operating characteristic (ROC) curve and calibration plot were adopted to evaluate the predictive power of our risk model. RESULTS: In the multivariable Cox regression analysis, five factors including presence of node-positive primary defined by enhanced CT/MR, preoperative CEA level, primary tumor location, tumor grade and number of liver metastases were identified as independent prognostic indicators of overall survival (OS) and adopted to formulate the nomogram. In the training cohort, calibration plot graphically showed good fitness between estimated and actual 1- and 3-year OS. Time-dependent ROC curve by Kaplan-Meier method showed that our nomogram model was superior to widely used Fong's score in prediction of 1- and 3-year OS (AUC 0.702 vs. 0.591 and 0.848 vs. 0.801 for 1- and 3-year prediction in validation cohort, respectively). Kaplan-Meier curves for patients stratified by the assessment of nomogram showed great discriminability (P<0.001). CONCLUSIONS: In this retrospective analysis we identified several preoperative factors affecting survival of synchronous CRLM patients undergoing simultaneous resection. We also constructed and validated a risk model which showed high accuracy in predicting 1- and 3-year survival after surgery. Our risk model is expected to serve as a predictive tool for CRLM patients receiving simultaneous resection and assist physicians to make treatment decision.

Corrigendum to "The Prognostic Significance of Tumor Deposit Count for Colorectal Cancer Patients after Radical Surgery".

[This corrects the article DOI: 10.1155/2020/2052561.].

Review of Denonvilliers' fascia: the controversies and consensuses.

The Denonvilliers' fascia (DVF) plays an important role in rectal surgery because of its anatomic position and its relationship to the surrounding organs. It affects the surgical plane anterior to the rectum in the procedure of total mesorectal excision (TME). Anatomical and embryological studies have helped us to understand this structure to some extent, but many controversies remain. In terms of its embryonical origin, there are three mainstream hypotheses: peritoneal fusion of the embryonic cul-de-sac, condensation of embryonic mesenchyme, and mechanical pressure. Regarding its architecture, the DVF may be a single, two, or multiple layers, or a composite single-layer structure. In women, most authors deem that this structure does exist but they are willing to call it the rectovaginal septum rather than the DVF. Operating behind the DVF is supported by most surgeons. This article will review those mainstream studies and opinions on the DVF and combine them with what we have observed during surgery to discuss those controversies and consensuses mentioned above. We hope this review may help young colorectal surgeons to have a better understanding of the DVF and provide a platform from which to guide future scientific research.

The Prognostic Significance of Tumor Deposit Count for Colorectal Cancer Patients after Radical Surgery.

BACKGROUND: The prognostic value of tumor deposit (TD) count in colorectal cancer (CRC) patients has been rarely evaluated. This study is aimed at exploring the prognostic value of TD count and finding out the optimal cutoff point of TD count to differentiate the prognoses of TD-positive CRC patients. METHOD: Patients diagnosed with CRC from Surveillance, Epidemiology, and End Results (SEER) database from January 1, 2010, to December 31, 2012, were analyzed. X-tile program was used to identify the optimal cutoff point of TD count in training cohort, and a validation cohort was used to test this cutoff point after propensity score matching (PSM). Univariate and multivariate Cox proportional hazard models were used to assess the risk factors of survival. RESULTS: X-tile plots identified 3 (P < 0.001) as the optimal cutoff point of TD count to divide the patients of training cohort into high and low risk subsets in terms of disease-specific survival (DSS). This cutoff point was validated in validation cohort before and after PSM (P < 0.001, P = 0.002). More TD count, which was defined as more than 3, was validated as an independent risk prognostic factor in univariate and multivariate analysis (P < 0.001). CONCLUSION: More TD count (TD count ≥ 4) was significantly associated with poor disease-specific survival in CRC patients.

Hepatocyte Nuclear Factor 3ß Plays a Suppressive Role in Colorectal Cancer Progression.

Background and Objective: Hepatocyte nuclear factor 3ß (HNF3ß) is a key transcription factor in the development of the gastrointestinal tract. However, only few studies have examined its' expression, function and potential clinical significance in colorectal cancer tumorigenesis and progression. Methods: HNF3ß expression in colorectal cancer tissue samples of 174 patients was assessed by immunohistochemistry. The results were analyzed with respect to patients' clinicopathological characteristics and survival. Following the in vitro cell transfection, MTT, wound healing, and Transwell assays were used to test cell proliferation, migration, and invasion, respectively. Western blot was used to examine IL6, JAK1, and STAT3 protein expression. The potential for tumor formation was evaluated using a mouse xenograft model. Results: HNF3ß expression was lower in colon cancer tissue compared to normal tissue and correlated with UICC clinical stage (P = 0.001), depth of invasion (P = 0.004), regional lymph node metastasis (P = 0.007), distant metastasis (P = 0.048), and poor survival (P < 0.001) in patients with colorectal cancer. Furthermore, HNF3ß overexpression impeded proliferation, migration and invasion of SW480 cells via JAK-STAT3 signaling in vitro. Moreso, HNF3ß overexpression showed a significant growth inhibition of subcutaneous xenograft tumors in vivo. Conclusions: The results show that HNF3ß acts as a suppressor of colorectal cancer progression and decreased HNF3 ß expression is closely related to the poor prognosis. Thus, HNF3ß may be a potential molecular target for inhibition of colorectal cancer cells and development of new anti-tumor therapies.

Alsterpaullone induces apoptosis of HepG2 cells via a p38 mitogen-activated protein kinase signaling pathway.

Alsterpaullone (Alp) is a small-molecule inhibitor that targets cyclin-dependent kinases to inhibit tumor cell activity. However, to the best of our knowledge, the effect of Alp on hepatoblastoma has not been investigated. Therefore, the function of Alp in apoptotic induction of hepatoblastoma cells and a potential mechanism of action were investigated. Results indicated that low doses of Alp (1 µM) significantly induced apoptosis in the HepG2 hepatoblastoma cell line. In vivo experiments of tumor suppression further indicated that Alp (3 mg/kg) exerted an inhibitory effect on HepG2 ×enograft tumor growth. Following Alp treatment, the expression level of B-cell lymphoma 2 (Bcl-2)-associated X protein, and cleaved caspase-3 and -9 in HepG2 cells was significantly increased; however, the expression of Bcl-2 was significantly decreased. In addition, phosphorylation of p38 mitogen-activated protein kinase (MAPK) significantly decreased Alp-induced caspase-3 and -9 activation. These results suggested that Alp induces apoptosis and inhibited proliferation via the p38MAPK signaling pathway. Therefore, Alp may be a therapeutic agent for treating hepatoblastoma.

Wuzhi capsule (Schisandra Sphenanthera extract) attenuates liver steatosis and inflammation during non-alcoholic fatty liver disease development.

OBJECTIVE: Wuzhi (WZ) capsule contains an ethanol extract of Schisandra sphenanthera. The efficacy of WZ in treating non-alcoholic fatty liver disease (NAFLD) has not yet been elucidated. The present study assessed the effects of WZ on NAFLD. MATERIAL AND METHODS: A C57BL/6 male mouse model of NAFLD was established by feeding the animals a methionine-choline-deficient (MCD) diet. Mice fed the basal diet were used as controls. Both groups were randomly administered WZ or vehicle by gavage for 5 weeks. Body weight change, liver/body weight ratio, metabolic parameters, and histological changes were assessed. Serum levels of IL-1ß, IL-6, IL-10, and TNF-α were analysed by ELISA; mRNA expression of these genes in the liver was studied by real-time PCR. Western blotting was used to analyse the protein levels of PPAR-α, PPAR-γ, MCAD, LCAD, and p65 in the liver. RESULTS: After 5 weeks of the MCD diet, the liver/body weight ratio of WZ mice was higher than that of control mice. Liver histology revealed significantly less steatosis, inflammation, and necrosis, which was confirmed by decreased intrahepatic triglycerides and serum ALT in WZ-treated mice. WZ also reduced the liver mRNA expression of IL-1ß, IL-6, and TNF-α and the serum levels of IL-1ß and IL-6. Sensitivity to steatohepatitis due to WZ administration correlated significantly with alterations in the expression of PPAR-α/γ, as well as the NF-κB signalling pathway. CONCLUSIONS: WZ plays a protective role against MCD-induced steatohepatitis. The underlying mechanism likely involves the upregulation of PPAR-α/γ and downregulation of the NF-κB signalling pathway. Based on its beneficial effects on the liver, WZ is a promising therapeutic for NAFLD patients.

Schisantherin A protects against liver ischemia-reperfusion injury via inhibition of mitogen-activated protein kinase pathway.

Schisantherin A (SchA) is a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera. The role of SchA in liver injury induced by ischemia and reperfusion (I/R) has not yet been elucidated. The present study hypothesized the protective effects of SchA in hepatic I/R model. Either sham laparotomy or hepatic I/R was induced in C57BL/6 male mice after SchA or vehicle administration. Liver function, histological damage, oxidative/nitrosative stress, inflammatory infiltration, cytokine production, cell apoptosis, cell autophagy, and I/R-associated intracellular signaling pathway were assessed to evaluate the impact of SchA pretreatment on I/R-induced liver injury. After liver I/R injury, the mice pretreated with appropriate SchA displayed significantly preserved liver function, less histological damage, ameliorated oxidative/nitrosative stress, attenuated inflammatory state, and reduced cell apoptosis. However, no differences in the autophagic response were detected after SchA pretreatment. The underlying protective mechanism putatively involves the inhibition of mitogen-activated protein kinase (MAPK) signaling pathway. Based on the beneficial effects, SchA pretreatment may serve as a potential prophylactic measure to prevent liver I/R injury related to various clinical conditions.

MiR-199a/b-5p inhibits hepatocellular carcinoma progression by post-transcriptionally suppressing ROCK1.

In this study, we explored the actions of miR-199a/b-5p during hepatocellular carcinoma (HCC) progression and its potential target genes. Through heatmap miRNA expression analysis of 15 matched HCC tumor and adjacent non-tumor liver tissues from the TCGA database, we detected 19 mRNAs that were upregulated and 13 that were downregulated specifically in HCC. Among these, miR-199 family members were downregulated in HCC tumors and cell lines, as compared to controls. Low miR-199a/b-5p expression was also associated with poor overall survival of HCC patients. miR-199a/b-5p overexpression in HCC cell lines inhibited cell proliferation, migration and invasion, both in vitro and in vivo. In addition, miR199-a/b-5p post-transcriptionally suppressed Rho-associated coiled-coil kinase 1 (ROCK1). This in turn led to inhibition of ROCK1/MLC and PI3K/Akt signaling, which is necessary for HCC proliferation and metastasis. These results indicate that miR-199a/b acts as tumor suppressors in HCC and represent promising therapeutic targets.

The role of pattern recognition receptors in the innate recognition of Candida albicans.

Candida albicans is both a commensal microorganism in healthy individuals and a major fungal pathogen causing high mortality in immunocompromised patients. Yeast-hypha morphological transition is a well known virulence trait of C. albicans. Host innate immunity to C. albicans critically requires pattern recognition receptors (PRRs). In this review, we summarize the PRRs involved in the recognition of C. albicans in epithelial cells, endothelial cells, and phagocytic cells separately. We figure out the differential recognition of yeasts and hyphae, the findings on PRR-deficient mice, and the discoveries on human PRR-related single nucleotide polymorphisms (SNPs).