Colorectal cancer-derived exosomal miR-106b-3p promotes metastasis by down-regulating DLC-1 expression.

Cancer-derived exosomal miRNAs play an important role in the development of metastasis, but the effects and underlying mechanisms remain unclear. In the present study, we investigated the miRNA expression profiles of 5 paired serum exosomal samples from metastatic colorectal cancer (mCRC) and non-mCRC patients via RNA sequencing. After we evaluated the differentially expressed miRNAs in 80 CRC patients, miR-106b-3p was selected as a metastasis-associated miRNA of CRC. We showed that the expression level of serum exosomal miR-106b-3p was significantly higher in CRC patients with metastasis than those without metastasis. Additionally, high serum exosomal miR-106b-3p expression in patients was correlated with a poor prognosis. Coculture of low-metastatic CRC cells with high-metastatic CRC cell-derived exosomes promoted cell migration, invasion, and epithelial-to-mesenchymal transition (EMT), which was caused by the transport and transduction of miR-106b-3p in vitro. Moreover, exosomal miR-106b-3p promoted lung metastasis of CRC cells in vivo. In addition, we demonstrated that miR-106b-3p regulated metastasis by targeting deleted in liver cancer-1 (DLC-1). A negative correlation was also identified between miR-106b-3p and DLC-1 expression in human CRC tumour tissues and in mouse lung metastatic lesions. Collectively, our study indicated that metastasis-associated miR-106b-3p from serum exosomes could be used as a potential prognostic biomarker and therapeutic target for CRC patients.

A novel and safe approach: middle cranial approach for laparoscopic right hemicolon cancer surgery with complete mesocolic excision.

BACKGROUND: Mastering right hemicolectomy techniques using laparoscopy in colorectal cancer surgery is very difficult. Although the long-term prognosis of laparoscopic right hemicolectomy (LRH) and complete mesocolic excision is unquestionable, different surgeons have their own opinions on routes of conducting LRH. OBJECTIVES: LRH surgery is very complex due to the upper abdominal anatomical structure and vascular variation. Therefore, it has been considered the most difficult of all colorectal cancer surgeries. Our innovative middle cranial approach (MCA) was developed to avoid unnecessary injuries and minimize the operative time, thereby reducing the patient's hospital stay and improving their short-term prognosis. METHODS: We compared 90 colon cancer patients who underwent the MCA between January 2016 and January 2017 with 82 patients who underwent the conventional central approach conducted by the same group of physicians (with Dr Cui as the surgeon) from 2011 to 2015. A short-term statistical analysis was performed. RESULTS: A total of 90 patients were included: 43 men and 47 women. Twenty-three patients underwent abdominal surgery (including stomach, rectum, and sigmoid colon surgery; appendectomy; and uterine attachment surgery). The median age of these patients was 62.6 (28-85) years; the median BMI was 22.9 (14.7-33.3) kg/m2; the mean bleeding volume was 53.9 (10-100) ml; the mean tumour diameter was 5.7 (0.8-9) cm, and the average number of lymph nodes detected was 19.2 (7-49). CONCLUSIONS: Our study showed that radical resection of right-sided colon cancer using the MCA was safe and feasible for the treatment of colorectal cancer patients.

The lncRNA CRNDE promotes colorectal cancer cell proliferation and chemoresistance via miR-181a-5p-mediated regulation of Wnt/ß-catenin signaling.

BACKGROUND: With more than 600,000 mortalities each year, colorectal cancer (CRC) is the third most commonly diagnosed type of cancer worldwide. Recently, mechanisms involving noncoding RNAs have been implicated in the development of CRC. METHODS: We examined expression levels of lncRNA CRNDE and miR-181a-5p in 64 cases of CRC tissues and cell lines by qRT-PCR. Gain-of-function and loss-of-function assays were performed to examine the effect of CRNDE and miR-181a-5p on proliferation and chemoresistance of CRC cells. Using fluorescence reporter and western blot assays, we also explored the possible mechanisms of CRNDE in CRC cells. RESULTS: In this study, we found that the expression levels of the CRNDE were upregulated in CRC clinical tissue samples. We identified microRNA miR-181a-5p as an inhibitory target of CRNDE. Both CRNDE knockdown and miR-181a-5p overexpression in CRC cell lines led to inhibited cell proliferation and reduced chemoresistance. We also determined that ß-catenin and TCF4 were inhibitory targets of miR-181a-5p, and that Wnt/ß-catenin signaling was inhibited by both CRNDE knockdown and miR-181a-5p overexpression. Significantly, we found that the repression of cell proliferation, the reduction of chemoresistance, and the inhibition of Wnt/ß-catenin signaling induced by CRNDE knockdown would require the increased expression of miR-181a-5p. CONCLUSIONS: Our study demonstrated that the lncRNA CRNDE could regulate the progression and chemoresistance of CRC via modulating the expression levels of miR-181a-5p and the activity of Wnt/ß-catenin signaling.

Cuproplasia characterization in colon cancer assists to predict prognosis and immunotherapeutic response.

Introduction: Colon cancer is the 3rd most prevalent cancer worldwide, with more than 900,000 deaths annually. Chemotherapy, targeted treatment, and immunotherapeutic treatment are the three cornerstones of colon cancer treatment; however, the occurrence of immune therapy resistance is the most pressing problem to solve. Copper is a mineral nutrient that is both beneficial and potentially toxic to cells and is increasingly implicated in cell proliferation and death pathways. Cuproplasia is characterized by copper-dependent cell growth and proliferation. This term encompasses both neoplasia and hyperplasia and describes the primary and secondary effects of copper. The connection between copper and cancer has been noted for decades. However, the relationship between cuproplasia and colon cancer prognosis remains unclear. Method: In this study, we applied bioinformatics approaches including WGCNA, GSEA and etc. to delineate cuproplasia characterization of colon cancer, set up a robust Cu_riskScore model based on cuproplasia-relevant genes and found its relevant biological processes use qRT-pCR to validate our results on our cohort. Result: The Cu_riskScore is found to be relevant to Stage and MSI-H subtype, and some biological processes including MYOGENESIS and MYC TARGETS. The Cu_riskScore high and low groups also showed different immune infiltration pattern and genomic traits. Finally, the result of our cohort showed the Cu_riskScore gene RNF113A has a marked effect in predicting immunotherapy response. Discussion: In conclusion, we identified a cuproplasia-related gene expression signature consisting of six genes and studied the landscape of the clinical and biological characterization of this model in Colon Cancer. Furthermore, the Cu_riskScore was demonstrated to be a robust prognostic indicator and predictive factor for the benefits of immunotherapy.

A Novel Quantification System Combining iTRAQ Technology and Multi-Omics Assessment to Predict Prognosis and Immunotherapy Efficacy in Colon Cancer.

Background: Colon cancer is one of the most common cancer types, although it has certain unique genetic features. This study aimed to develop a unique score for assessing prognosis and immunotherapy efficacy using integrated multi-omics analysis. Methods: Isobaric tagging for relative and absolute quantification (iTRAQ) based proteomic analysis was used to screen differentially expressed proteins (DEP) between tumor and normal samples. DEP mRNA obtained from TCGA were clustered into different categories to show landscape-related prognosis and function. Following that, DEG was extracted from DEP mRNA, and the DEP-related score (DEPRS) was constructed to investigate the difference in immunotherapy prognosis and sensitivity. Finally, WCGNA, random forest, and artificial neural networks were used to screen for key genes. The prognostic value and protein level of these genes were validated. Results: A total of 243 DEPs were identified through iTRAQ analysis, and the corresponding DEP mRNA was clustered into three. Following a series of tests, 1,577 DEGs were identified from overlapped DEP mRNA clusters and were classified into three gene clusters. The two types of clusters described above shared comparable characteristics in terms of prognosis and function. Then, it was established that a high DEPRS indicated a poor prognosis and DEPRS had significant associations with TMB, MSI status, and immunotherapeutic response. Finally, the key genes HART3 and FBLN2 were identified and were found to be implicated in immunotherapy and prognosis. Conclusion: The development of a DEPRS based on multi-omics analysis will aid in improving our understanding of colon cancer and guiding a more effective immunotherapy strategy. DEPRS and key genes are used as biomarkers in the clinical evaluation of patients.

Bisphenol A Promotes the Progression of Colon Cancer Through Dual-Targeting of NADPH Oxidase and Mitochondrial Electron-Transport Chain to Produce ROS and Activating HIF-1α/VEGF/PI3K/AKT Axis.

Bisphenol A (BPA) is a high-production-volume industrial chemical. Despite recent research conducted on its carcinogenicity, its role in the development of colon cancer (CC) has been rarely studied. This study aims to evaluate the effects of BPA on the migration and invasion of CC cells. First, we clinically verified that patients with CC exhibit higher serum BPA level than healthy donors. Subsequently, different CC cell lines were exposed to a series of BPA concentrations, and the migration and invasion of cells were detected by the wound healing test and transwell assay. Finally, N-acetyl-L-cysteine (NAC) and siHIF-1α intervention was used to explore the effects of ROS and HIF-1α on cell migration and invasion, respectively. The results demonstrated that the occurrence of BPA-induced migration and invasion were dependent on the dose and time and was most pronounced in DLD1 cells. ROS production was jointly driven by NADPH oxidase (NOX) and mitochondrial electron-transport chain (ETC). Furthermore, the intervention of NAC and siHIF-1α blocked the HIF-1α/VEGF/PI3K/AKT axis and inhibited cell migration and invasion. In conclusion, our results suggest that BPA exposure promotes the excessive production of ROS induced by NOX and ETC, which in turn activates the HIF-1α/VEGF/PI3K/AKT axis to promote the migration and invasion of CC cells. This study provides new insights into the carcinogenic effects of BPA on CC and warns people to pay attention to environmental pollution and the harm caused to human health by low-dose BPA.

The risk of developing second primary malignancies among colorectal cancer patients.

BACKGROUND: The increasing number of young colorectal cancer (CRC) survivors has led to ongoing concerns about the risk of secondary primary malignancies (SPMs). Here, we intended to comprehensively explore the pooled standardized incidence rates (SIRs) for total and site-specific SPMs in CRC survivors with different restriction to lag period. METHODS: Pubmed, Embase, Cochrane Library, and Web of science databases were searched to identify any studies reporting the SIRs of SPM following CRC until August 2021. Total and site-specific SIRs with different restriction to lag period were pooled using fixed/random effect models. RESULTS: A total of 42 full-text publications with more than 1, 524, 236 CRC survivors and 166, 210 SPM patients were included in the meta-analysis. Pooled data showed an increased SIRs for all SPMs in CRC survivors with different restriction to lag period (no restriction to lag period, SIR = 1.15, 95% CI = [1.08-1.23]; 1-year lag, 1.16 [1.10-1.23]; 5-year lag, 1.18 [1.09-1.28]; 10-year lag, 1.24 [1.11-1.39]). The conclusions were consistent for neoplasms of colorectum, corpus uteri, and small intestine with different restriction to lag period. However, limited evidence was presented for associations between CRC survivors and SPM for prostate, breast (female), ovarian, stomach, urinary bladder, kidney, thyroid, bone and soft tissue. CONCLUSION: CRC survivors are associated with an increased risk of SPMs, especially neoplasms of colorectum, corpus uteri, and small intestine. Further studies should explore the risks for these neoplasms in CRC survivors, thus providing the reference for future follow-up care.

Prognostic and therapeutic significance of a novel ferroptosis related signature in colorectal cancer patients.

Increasing studies have highlighted the importance of ferroptosis in colorectal cancer (CRC). However, how to use ferroptosis-related genes (FRGs) to predict the prognosis and guide the treatment of CRC remains unknown. To build a prognostic prediction model using the GEO and TCGA databases and explored a therapeutic strategy for CRC patients based on FRGs. A total of 60 FRGs were identified and three of them including ACACA, GSS, and NFS1 were associated with the prognosis of CRC. Using Lasso regression analysis, an FRGs signature was constructed and validated as an independent prognostic predictor. Then we developed a nomogram based on the FRGs signature and clinical prognostic factors to predict the prognosis of CRC patients, which was better than the traditional TNM staging system. Single-sample gene set enrichment analysis (ssGSEA) was further performed for the functional analysis and suggested that JAK-STAT signaling, Ras signaling pathway, MAPK signaling pathway, and PI3K-Akt signaling pathway were significantly enriched in CRC patients with higher FRGs risk score. Interestingly, CRC cells with higher FRGs risk score were more sensitive to RSL3. Knocking down GSS and NFS1 increased the FRGs risk score and the sensitivity of CRC cells to RSL3. For the clinic use, we screened 75 FDA-approved cancer drugs and found that Fludarabine phosphate could decrease the expression of GSS and NFS1 most. Fludarabine phosphate, in combination with RSL3, showed a strong synergistic effect on CRC cells. Together, this study identified a potent prognostic model and provided an alternative individualized treatment for CRC patients.

Identification and Validation in a Novel Quantification System of Ferroptosis Patterns for the Prediction of Prognosis and Immunotherapy Response in Left- and Right-Sided Colon Cancer.

Background: This study aimed to establish a novel quantification system of ferroptosis patterns and comprehensively analyze the relationship between ferroptosis score (FS) and the immune cell infiltration (ICI) characterization, tumor mutation burden (TMB), prognosis, and therapeutic sensitivity in left-sided and right-sided colon cancers (LCCs and RCCs, respectively). Methods: We comprehensively evaluated the ferroptosis patterns in 444 LCCs and RCCs based on 59 ferroptosis-related genes (FRGs). The FS was constructed to quantify ferroptosis patterns by using principal component analysis algorithms. Next, the prognostic value and therapeutic sensitivities were evaluated using multiple methods. Finally, we performed weighted gene co-expression network analysis (WGCNA) to identify the key FRGs. The IMvigor210 cohort, TCGA-COAD proteomics cohort, and Immunophenoscores were used to verify the predictive abilities of FS and the key FRGs. Results: Two ferroptosis clusters were determined. Ferroptosis cluster B demonstrated a high degree of congenital ICI and stromal-related signal enrichment with a poor prognosis. The prognosis, response of targeted inhibitors, and immunotherapy were significantly different between high and low FS groups (HSG and LSG, respectively). HSG was characterized by high TMB and microsatellite instability-high subtype with poor prognosis. Meanwhile, LSG was more likely to benefit from immunotherapy. ALOX5 was identified as a key FRG based on FS. Patients with high protein levels of ALOX5 had poorer prognoses. Conclusion: This work revealed that the evaluation of ferroptosis subtypes will contribute to gaining insight into the heterogeneity in LCCs and RCCs. The quantification for ferroptosis patterns played a non-negligible role in predicting ICI characterization, prognosis, and individualized immunotherapy strategies.

Exploring biomarkers for prognosis and neoadjuvant chemosensitivity in rectal cancer: Multi-omics and ctDNA sequencing collaboration.

Introduction: This study aimed to identified the key genes and sequencing metrics for predicting prognosis and efficacy of neoadjuvant chemotherapy (nCT) in rectal cancer (RC) based on genomic DNA sequencing in samples with different origin and multi-omics association database. Methods: We collected 16 RC patients and obtained DNA sequencing data from cancer tissues and plasma cell-free DNA before and after nCT. Various gene variations were analyzed, including single nucleotide variants (SNV), copy number variation (CNV), tumor mutation burden (TMB), copy number instability (CNI) and mutant-allele tumor heterogeneity (MATH). We also identified genes by which CNV level can differentiate the response to nCT. The Cancer Genome Atlas database and the Clinical Proteomic Tumor Analysis Consortium database were used to further evaluate the specific role of therapeutic relevant genes and screen out the key genes in multi-omics levels. After the intersection of the screened genes from differential expression analysis, survival analysis and principal components analysis dimensionality reduction cluster analysis, the key genes were finally identified. Results: The genes CNV level of principal component genes in baseline blood and cancer tissues could significantly distinguish the two groups of patients. The CNV of HSP90AA1, EGFR, SRC, MTOR, etc. were relatively gained in the better group compared with the poor group in baseline blood. The CNI and TMB was significantly different between the two groups. The increased expression of HSP90AA1, EGFR, and SRC was associated with increased sensitivity to multiple chemotherapeutic drugs. The nCT predictive score obtained by therapeutic relevant genes could be a potential prognostic indicator, and the combination with TMB could further refine prognostic prediction for patients. After a series of analysis in multi-omics association database, EGFR and HSP90AA1 with significant differences in multiple aspects were identified as the key predictive genes related to prognosis and the sensitivity of nCT. Discussion: This work revealed that effective combined application and analysis in multi-omics data are critical to search for predictive biomarkers. The key genes EGFR and HSP90AA1 could serve as an effective biomarker to predict prognose and neoadjuvant chemosensitivity.

Identification of sixteen metabolic genes as potential biomarkers for colon adenocarcinoma.

PURPOSE: To identify some key prognosis-related metabolic genes (PRMG) and establish a clinical prognosis model for colon adenocarcinoma (COAD) patients. METHODS: We used The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to obtain gene expression profiles of COAD, and then identified differentially expressed prognostic-related metabolic genes through R language and Perl software, Through univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) Cox analysis to obtain target genes, established metabolic genes prognostic models and risk scores. Through Cox regression analysis, independent risk factors affecting the prognosis of COAD were analyzed, and receiver operating characteristics (ROC) curve analysis of independent prognostic factors was performed and a nomogram for predicting overall survival was constructed. We performed the consistency index (C-index) test and decision curve analysis (DCA) on the nomogram, and used gene set enrichment analysis (GSEA) to identify the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of model genes. We selected PRMG based on the expression of metabolic genes, and used LASSO Cox regression to construct 16 metabolic gene models (SEPHS1, P4HA1, ENPP2, PTGDS, GPX3, CP, ASPA, POLR3A, PKM, POLR2D , XDH, EPHX2, ADH1B, HMGCL, GPD1L and MAOA). RESULTS: The risk score generated from our model can well predict the survival prognosis of COAD. A nomogram based on the clinicopathological characteristics and risk scores of COAD can personally predict the overall survival rate of COAD patients. CONCLUSIONS: The risk score based on the expression of 16 metabolic genes can effectively predict the prognosis of patients with COAD.

The oncogenic role of LncRNA FAM83C-AS1 in colorectal cancer development by epigenetically inhibits SEMA3F via stabilizing EZH2.

Inactivation of Semaphorin 3F (SEMA3F) is involved in colorectal cancer development. However, the mechanism by which SEMA3F is regulated remains elusive. Deregulation of lncRNAs have been implicated in multiple human malignancies, including colorectal cancer (CRC). To date, it is still unclear whether and how lncRNA regulates SEMA3F expression and mediates CRC progression. Here we identify the oncogenic role of lncRNA FAM83C antisense RNA 1 (FAM83C-AS1) in CRC. FAM83C-AS1 is upregulated in tumor tissues and cells of CRC, which is negatively correlated with SEMA3F expression. Reciprocally, knockdown of FAM83C-AS1 exhibits inhibitory effects on the malignant transformation of CRC. Moreover, our data uncover that FAM83C-AS1 enhances methylation of SEMA3F promoter H3K27me3 via upregulating methyltransferase enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2). Specifically, FAM83C-AS1 stabilizes EZH2 protein through recruiting the zinc finger RANBP2-type containing 1 (ZRANB1). Both in vitro and in vivo rescue assays exhibit that SEMA3F is dispensable for the tumor-promoting effects of FAM83C-AS1 on CRC progression. Our data thus demonstrate that the epigenetic role of FAM83C-AS1 in suppression of SEMA3F expression through stabilization of EZH2 to drive CRC progression, which may be conducive to discovering novel therapeutic targets for the treatment of CRC.

LncRNA EGOT regulates the proliferation and apoptosis of colorectal cancer by miR-33b-5p/CROT axis.

Accumulating researches have proved that long noncoding RNAs (lncRNAs) regulate a variety of cellular processes during cancer progression. However, the detailed function of most lncRNAs in colorectal cancer (CRC) remains mostly unknown. This study was aimed at exploring the specific role of lncRNA EGOT in CRC. Data from this study revealed that EGOT expression was obviously upregulated in CRC tissues and cell lines, and high EGOT expression indicated poor overall survival of CRC patients. Besides, functional assays proved that EGOT knockdown inhibited cell proliferation and promoted cell apoptosis in CRC. Then, subsequent molecular mechanism assays uncovered that EGOT could bind with miR-33b-5p and negatively regulate miR-33b-5p expression. Additionally, CROT was a downstream target of miR-33b-5p. Further, rescued-function assays suggested that the suppressive influence of EGOT depletion on CRC progression was reversed by miR-33b-5p inhibition or CROT overexpression. In conclusion, lncRNA EGOT mediates the tumor-facilitating part in CRC via miR-33b-5p/CROT pathway.

High extracellular pressure promotes gastric cancer cell adhesion, invasion, migration and suppresses gastric cancer cell differentiation.

Slightly increased pressure stimulates tumor cell adhesion and proliferation. In the present study, we aimed to evaluate the effects of high pressure on gene expression and the biological behavior of gastric cancer cells. After incubation for 30 min at 37˚C under ambient and increased pressure, one portion of SGC7901 cells was used for cell proliferation and apoptosis assays, cell cycle analysis, adhesion invasion or migration assays. The other portion of cells was harvested for detection of matrix metalloproteinase-2 (MMP-2), inhibitor of DNA binding-1 (ID1), sonic Hedgehog (SHH) and E-cadherin expression by western blotting or RT-PCR. In addition, we investigated the effects of high pressure on SGC7901 cell ultrastructure by transmission electron microscopy. We found that the adhesion fold under increased pressure of 760 and 1,520 mmHg was 2.39±1.05 (P<0.05) and 2.47±0.85 (P<0.01) as compared with the control, respectively. The invasion fold was 3.42±2.06 (P<0.05) and 5.13±2.49 (P<0.01) as compared with the control, respectively. The migration was 1.65±0.20 (P<0.001) and 2.53±0.50 (P<0.001) as compared with the control, respectively. At increased pressure, MMP-2 and ID1 expression increased significantly, while the expression of SHH decreased significantly. However, we did not find significant change in proliferation, apoptosis, cell cycle or ultrastructure of the SGC7901 cells under high pressure. In conclusion, high pressure promoted the adhesion, invasion and migration of SGC7901 cells. Moreover, the present study suggests that the pressure-augmented invasion and migration may be related to the increase in MMP-2 expression. Moreover, high pressure may suppress SGC7901 cell differentiation, which may result from the change in SHH and ID1 expression.