Genome wide-scale CRISPR-Cas9 knockout screens identify a fitness score for optimized risk stratification in colorectal cancer.

BACKGROUND: The molecular complexity of colorectal cancer poses a significant challenge to the clinical implementation of accurate risk stratification. There is still an urgent need to find better biomarkers to enhance established risk stratification and guide risk-adapted treatment decisions. METHODS: we systematically analyzed cancer dependencies of 17 colorectal cancer cells and 513 other cancer cells based on genome-scale CRISPR-Cas9 knockout screens to identify colorectal cancer-specific fitness genes. A regression model was built using colorectal cancer-specific fitness genes, which was validated in other three independent cohorts. 30 published gene expression signatures were also retrieved. FINDINGS: We defined a total of 1828 genes that were colorectal cancer-specific fitness genes and identified a 22 colorectal cancer-specific fitness gene (CFG22) score. A high CFG22 score represented unfavorable recurrence and mortality rates, which was validated in three independent cohorts. Combined with age, and TNM stage, the CFG22 model can provide guidance for the prognosis of colorectal cancer patients. Analysis of genomic abnormalities and infiltrating immune cells in the CFG22 risk stratification revealed molecular pathological difference between the subgroups. Besides, drug analysis found that CFG22 high patients were more sensitive to clofibrate. INTERPRETATION: The CFG22 model provided a powerful auxiliary prediction tool for identifying colorectal cancer patients with high recurrence risk and poor prognosis, optimizing precise treatment and improving clinical efficacy.

Doping proanthocyanidins into gel/zirconium hybrid hydrogel to reshape the microenvironment of diabetic wounds for healing acceleration.

Infection and chronic inflammation caused by oxidative stress are major challenges in chronic wound healing. Preparing a simple, efficient hydrogel with reactive oxygen-scavenging properties for chronic wound repair is a promising strategy. Herein, we report an injectable, self-repairing hydrogel with antioxidant and antibacterial properties that can be used to regenerate diabetic wounds. Hydrogels are prepared by coordination crosslinking of gelatin (Gel), a natural biopolymer derived from collagen, with Zr4+. Because of the dynamic properties of metal ion coordination bonds and the bactericidal effect of Zr4+, the obtained coordination hydrogels exhibit self-healing, injectable, and antibacterial properties. The plant polyphenol "proanthocyanidins," which has reactive oxygen-scavenging and anti-inflammatory effects, was simultaneously loaded into the coordination hydrogel during cross-linking. We obtained a versatile hydrogel that is easy to prepare, resistant to mechanical irritation, and antioxidant, and antibacterial in vitro. We further demonstrated that the injectable self-healing hydrogels could effectively repair diabetic skin wounds and accelerate collagen deposition and wound healing. This study shows that the multifunctional antioxidant hydrogel has great potential in developing multifunctional biomaterials for chronic wound healing.

Regorafenib activates oxidative stress by inhibiting SELENOS and potentiates oxaliplatin-induced cell death in colon cancer cells.

Colorectal cancer (CRC) is the third most common cancer, and is one of the leading causes of cancer-related death worldwide. At the time of diagnosis, about 20% of patients with CRC present metastatic disease. Regorafenib, an oral multi-kinase inhibitor, has been demonstrated the efficacy and tolerability in patients with metastatic CRC. Oxaliplatin is a frontline treatment regimen for CRC, and combination treatments with oxaliplatin and other chemotherapeutic agents exert superior therapeutic effects. However, side effects and drug resistance limited their further clinical application. Here, we found that combined treatment with regorafenib and oxaliplatin synergistically enhanced anti-tumor activities in CRC by activating reactive oxygen species (ROS) mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 signaling pathways. Regorafenib promoted ROS production by suppressing the expression of selenoprotein S (SELENOS). Knocking down SELENOS sensitized ROS-mediated anti-tumor effects of regorafenib in CRC cells. Furthermore, mouse xenograft models demonstrated that synergistic anti-tumor effects of combined treatment with regorafenib and oxaliplatin. This study provided solid experimental evidences for the combined treatment with regorafenib and oxaliplatin in CRC.

Malnutrition and visceral obesity predicted adverse short-term and long-term outcomes in patients undergoing proctectomy for rectal cancer.

BACKGROUND: To the best of our knowledge, no previous studies have explored the relationship between visceral obesity and malnutrition. Therefore, this study has aimed to investigate the association between them in patients with rectal cancer. METHODS: Patients with rectal cancer who underwent proctectomy were included. Malnutrition was defined according to the Global Leadership Initiative on Malnutrition (GLIM). Visceral obesity was measured using computed tomography (CT). The patients were classified into four groups according to the presence of malnutrition or visceral obesity. Univariate and multivariate logistic regression analyses were performed to evaluate risk factors for postoperative complications. Univariate and multivariate cox regression analyses were performed to evaluate the risk factors for overall survival (OS) and cancer-specific survival (CSS). Kaplan-Meier survival curves and log-rank tests were performed for the four groups. RESULTS: This study enrolled 624 patients. 204 (32.7%) patients were included in the well-nourished non-visceral obesity (WN) group, 264 (42.3%) patients were included in the well-nourished visceral obesity (WO) group, 114 (18.3%) patients were included in the malnourished non-visceral obesity (MN) group, and 42 (6.7%) patients were included in the malnourished visceral obesity (MO) group. In the multivariate logistic regression analysis, the Charlson comorbidity index (CCI), MN, and MO were associated with postoperative complications. In the multivariate cox regression analysis, age, American Society of Anesthesiologists (ASA) score, tumor differentiation, tumor node metastasis (TNM), and MO were associated with worsened OS and CSS. CONCLUSIONS: This study demonstrated that the combination of visceral obesity and malnutrition resulted in higher postoperative complication and mortality rates and was a good indicator of poor prognosis in patients with rectal cancer.

The geriatric nutritional risk index is an effective tool to detect GLIM-defined malnutrition in rectal cancer patients.

Background: This study aimed to investigate the value of the Geriatric Nutritional Risk Index (GNRI), prognostic nutritional index (PNI), and advanced lung cancer inflammation index (ALI) scores in detecting malnutrition in patients with rectal cancer; the Global Leadership Initiative on Malnutrition (GLIM) was used as the reference criterion. Materials and methods: This study included patients with rectal cancer who underwent proctectomy. GNRI, PNI, and ALI were calculated to detect the GLIM-defined malnutrition using the Receiver operating characteristic (ROC) curves. Univariate and multivariate logistic regression analyses were used to evaluate the association between the nutritional tools and postoperative complications. Kaplan-Meier survival curves, log-rank tests, and univariate and multivariate Cox regression analyses were used to clarify the relationship between nutritional tools and overall survival (OS). Results: This study enrolled 636 patients with rectal cancer. The GNRI demonstrated the highest sensitivity (77.8%), pretty specificity (69.0%), and the largest AUC (0.734). The GNRI showed good property in predicting major postoperative complications. All three nutritional tools were independent predictors of OS. Conclusion: The GNRI can be used as a promising alternative to the GLIM and is optimal in perioperative management of patients with rectal cancer.

Outcomes of Modified Tissue Selection Therapy Stapler in the Treatment of Prolapsing Hemorrhoids.

Objective: Tissue selection therapy staplers (TSTs) are widely used to treat prolapsing hemorrhoids; however, some disadvantages exist. We describe a modified technique for the treatment of prolapsing hemorrhoids, with the aim of minimizing the risk of anal stenosis and anal incontinence and reducing the impact of postoperative complications from the stapling technique. We applied a modified TST procedure, and the preliminary data were used to test the efficacy and safety of this new technique. Methods: We conducted a retrospective study of patients who underwent modified TST for prolapsing hemorrhoids at our department between January 2018 and January 2020. All patients received a modified TST. Most prolapsing hemorrhoids were not segmentally resected and were instead selectively removed. The demographics, preoperative characteristics, postoperative complications, therapeutic effects, and patient satisfaction were collected and analyzed. Results: A total of 106 patients were included in the study; 53 were men and 53 women (mean age, 49.24 years). The mean operative time was 55.01 min, and the mean hospital stay was 7.82 days. After surgery, three patients experienced bleeding (2.83%), 2 patients experienced anal discharge (1.89%), 2 patients experienced tenesmus (1.89%), and 5 patients experienced anal tags (4.72%). Anal incontinence, persistent post stapler pain, rectovaginal fistula and anal stenosis did not occur. Two patients developed recurrent symptomatic hemorrhoids (1.89%). The total effective rate of the surgery and the total satisfaction rate of the patients was 97.17%. Conclusions: The modified tissue selection therapy stapler technique was a satisfactory and economical treatment for prolapsing hemorrhoids at a follow-up period of 1 year. The modified TST was associated with reduced anal stenosis and anal incontinence, less persistent post stapler pain and a minimal risk of rectovaginal fistula.

Suppression of human colon tumor by EERAC through regulating Notch/DLL4/Hes pathway inhibiting angiogenesis in vivo.

Background: Ethanol extracted from radix of Actinidia chinensis (EERAC) has been proved to be effective to inhibit colorectal cancer (CRC). Notch signaling pathway and angiogenesis in tumors are closely related with the progression of CRC. However, if EERAC could influence CRC through Notch signaling pathway and angiogenesis remains unclear. Methods: Flow cytometry, transwell, wound healing methods were used to measure cell apoptosis, invasion, migration, and proliferation. Protein and mRNA expression were detected using qRT-PCR and western blotting. Immunofluorescence staining was applied to detect the expression of target protein in the tissues. Results: The invasion, migration, and proliferation of CRC cells were remarkably suppressed by ERRAC. Significant promotion of cell apoptosis and cell ration in S stage were observed after EERAC treatment. The Notch1/DLL4/Hes1 signaling pathway and angiogenesis were suppressed by EERAC. Overexpression of LIM domain-binding 2 (LDB2) remarkably weakened the influence of ERRAC on the viability of CRC cells. Conclusions: EERAC might suppress CRC through targeting Notch/DLL4/Hes1 pathway and inhibiting angiogenesis in tumors. This study might provide novel thought for the prevention and therapy of CRC through targeting Notch/DLL4/Hes1.

Ethanol Extracted from Radix of Actinidia Chinensis Inhibits Human Colon Tumor Through Inhibiting Notch-signaling Pathway.

Background: Colorectal cancer (CRC) is one of the most common tumors, and its five-year survival is still very low despite of the advance of treatment strategies. The antitumor effect of ethanol extracted from radix of Actinidia chinensis (EERAC) were identified in human colon cancer cells, but the underlying mechanism remains unclear. Methods: Cell proliferation, migration, and invasion were measured with cell counting kit-8 (CCK-8), wound healing, and transwell assays. Cell apoptosis and cycle were detected by flow cytometry. Western blotting and qRT-PCR were used to measure expression of target molecules. Xenograft tumor assay was applied to detect the influence of EERAC on tumor growth. Results: we found that EERAC inhibited the cell viability, migration, and invasion of SW480 cells in a concentration dependent manner, but promoted apoptosis and the cell percentage in S phase significantly. The suppression of notch-signaling pathway molecules, Notch1, Jagged1, and c-Myc, by EERAC was confirmed using western blotting and immunohistochemical staining. The significant inhibition of tumor growth by EERAC was also observed. Meanwhile, EERAC remarkably reversed the effects of mastermind like transcriptional coactivator 1 (MAML1, activator of notch-signaling pathway) on cell survival of SW480. Conclusions: EERAC might be a promising chemotherapeutic agent for CRC treatment.

Marital status and survival in patients with rectal cancer: An analysis of the Surveillance, Epidemiology and End Results (SEER) database.

BACKGROUND: Marital status has been validated as an independent prognostic factor for survival in several cancer types, but is controversial in rectal cancer (RC). The objective of this study was to investigate the impact of marital status on the survival outcomes of patients with RC. METHODS: We extracted data of 27,498 eligible patients diagnosed with RC between 2004 and 2009 from the Surveillance, Epidemiology and End Results (SEER) database. Patients were categorized into married, never married, divorced/separated and widowed groups.We used Chi-square tests to compare characteristics of patients with different marital status.Rectal cancer specific survival was compared using the Kaplan-Meier method,and multivariate Cox regression analyses was used to analyze the survival outcome risk factors in different marital status. RESULTS: The widowed group had the highest percentage of elderly patients and women,higher proportion of adenocarcinomas, and more stage I/II in tumor stage (P < 0.05),but with a lower rate of surgery compared to the married group (76.7% VS 85.4%). Compared with the married patients, the never married (HR 1.40), widowed (HR 1.61,) and divorced/separated patients (HR 1.16) had an increased overall 5-year mortality. A further analysis showed that widowed patients had an increased overall 5-year cause-specific survival(CSS) compared with married patients at stage I(HR 1.92),stage II (HR 1.65),stage III (HR 1.73),and stage IV (HR 1.38). CONCLUSION: Our study showed marriage was associated with better outcomes of RC patients, but unmarried RC patients, especially widowed patients,are at greater risk of cancer specific mortality.

Activation of IRE1α-XBP1 pathway induces cell proliferation and invasion in colorectal carcinoma.

Cell proliferation and tumor metastasis are considered as the main reasons for death in colorectal carcinoma (CRC). IRE1α-XBP1 pathway is the most conserved UPR pathways, which are activated during ER stress caused by the accumulation of unfolded or misfolded protein in the lumen of ER. Here, we demonstrated the critical role of IRE1α-XBP1 pathway and underlying molecular mechanism in cell proliferation and tumor metastasis in CRC. By the use of tissue microarray analysis of samples from 119 patients with CRC, IRE1α was determined to be an independent predictor of overall survival as higher expression of IRE1α in CRC patients showed lower survival rates (p = 0.0041). RNA interference and ectopic expression of IRE1α were applied to determine the molecular effects of IRE1α in CRC cells. The silencing of IRE1α inhibited the proliferation and blocked the invasion of CRC cells in vitro, while ectopic expression of IRE1α in turn promoted cell proliferation and invasion. IRE1α-XBP1 pathway regulated the mitosis of CRC cells through the directly binding of XBP1s to Cyclin D1 promoter to activate Cyclin D1 expression. Our results reveal that IRE1α-XBP1 pathway plays an important role in tumor progression and epithelial-to-mesenchymal transition (EMT), and IRE1α could be employed as a novel prognostic marker and a promising therapeutic target for CRC.

Immunohistochemical expression of Notch1, Jagged1, NF-κB and MMP-9 in colorectal cancer patients and the relationship to clinicopathological parameters.

BACKGROUND: Activation of Notch and NF-κB signaling has been frequently observed in colorectal cancer (CRC) patients and contributes to the chemo-resistance and treatment failure. However, the relationship between these signaling pathways and CRC has not been clearly described. OBJECTIVE: To investigate the expression of Notch1, Jagged1, NF-κB and MMP-9 in CRC patients and analyze their correlation with clinicopathological factors. METHODS: Expression of Notch1, Jagged1, NF-κB and MMP-9 was visualized by immune-histology in the tumor tissue, adjacent and distant normal tissues from 47 CRC patients without receiving chemotherapy or radiotherapy. RESULTS: Notch1 (80.8%), Jagged1 (80.8%), NF-κB (70.2%) and MMP-9 (76.6%) were overexpressed in cancer tissues compared normal tissues (P< 0.05). The intensity of Notch1, Jagged1 and NF-κB expression was associated with histological grading, depth of invasion, TNM staging and lymph node metastasis of CRC. MMP-9 was intimately correlated with depth of invasion, TNM staging and lymph node metastasis. NF-κB, MMP-9 and Notch1 expression was positively correlated (P< 0.05), and the same positive correlation was found among NF-κB, MMP-9 and Jagged1 expression (P< 0.05). CONCLUSION: Notch1, Jagged1, NF-κB and MMP-9 probably play a pivotal role during the CRC development, serving as biomarkers for early detection of the recurrence and metastasis and prognosis of CRC.

Clinicopathological significance and potential drug target of O6-methylguanine-DNA methyltransferase in colorectal cancer: a meta-analysis.

Emerging evidence indicates that O(6)-methylguanine-DNA methyltransferase (MGMT) is a candidate for tumor suppression in several types of human tumors including colorectal cancer (CRC). However, the correlation between MGMT hypermethylation and clinicopathological characteristics of CRC remains unclear. In this study, we conducted a systematic review and meta-analysis to quantitatively evaluate the effects of MGMT hypermethylation on the incidence of CRC and clinicopathological characteristics. A comprehensive literature search was done from Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, and the Chinese Biomedical Database for related research publications written in English and Chinese. Methodological quality of the studies was also evaluated. Analyses of pooled data were performed with Review Manager 5.2. Odds ratio (OR) and hazard ratio (HR) were calculated and summarized, respectively. Final analysis from 28 eligible studies was performed. MGMT hypermethylation is found to be significantly higher in CRC than in normal colorectal mucosa, the pooled OR from 13 studies including 1085 CRC and 899 normal colorectal mucosa, OR = 6.04, 95 % confidence interval (CI) = 4.69-7.77, p < 0.00001. MGMT hypermethylation is also significantly higher in colorectal adenoma than in normal colorectal mucosa, but it is significantly less compared to that in CRC patients. Interestingly, MGMT hypermethylation is correlated with sex status and is significantly higher in female than in male. MGMT hypermethylation is also associated with high levels of microsatellite instability (MSI). The pooled HR for overall survival (OS) shows that MGMT hypermethylation is not associated with worse survival in CRC patients. The results of this meta-analysis suggest that MGMT hypermethylation is associated with an increased risk and high levels of MSI and may play an important role in CRC initiation. However, MGMT hypermethylation may play an important role in the early stage of CRC progression and development, as well as having limited value in prediction of prognosis in CRC patients. We also discussed that MGMT may serve as a potential drug target of CRC.

[Efficacy of retained rectal posterior mucosa in procedure for prolapse and hemorrhoids].

OBJECTIVE: To evaluate the efficacy and necessity of retained rectal posterior mucosa in procedure for prolapse and hemorrhoids (PPH). METHODS: Clinical data of 260 cases with severe hemorrhoids in our hospital from January 2010 to May 2012 were analyzed retrospectively. A total of 132 cases with severe hemorrhoids excluding in rectal posterior wall were enrolled in retained rectal posterior mucosa in PPH (improvement group), other 128 cases of severe hemorrhoids were assigned to PPH (conventional group). Operative parameters, efficacy and complication after operation were compared. RESULTS: Two groups of patients received successful operations. Postoperative pain duration, frequency of analgesic drugs and postoperative hospital stay in improvement group were significantly reduced [(1.3 ± 0.5) d vs. (4.8 ± 0.7) d, 1.1 ± 0.3 vs. 5.9 ± 0.6, (5.2 ± 0.8) d vs. (5.8 ± 0.5) d, all P<0.01]. Incidence of anastomotic stenosis, heavy feeling in the anus and delayed bleeding in improvement group were significantly lower than those in conventional group (0 vs. 7.8%, 0.8% vs. 14.1%, 0 vs.7.8%, all P<0.01). CONCLUSIONS: The application of retained rectal posterior mucosa in PPH to patients with severe hemorrhoids excluding in rectal posterior wall can significantly reduce postoperative complications. But long-term efficacy needs further observation.