Association Between Vitamin B12 Intake and Mortality in Patients with Colorectal Cancer: The US National Health and Nutrition Examination Survey, 1999-2018.

Vitamin B12 plays a role in DNA methylation, influencing the 1-carbon cycle; However, its effect on colorectal cancer (CRC) mortality remains uncertain. This study assessed the relationship between vitamin B12 intake and all-cause and cancer-specific mortality among CRC patients. We analyzed data from the NHANES from 1999 to 2018, using multivariable Cox regression, competing risk model, Kaplan-Meier survival curves, and stratified analysis with interaction effects. The studied involved 4,554 cancer patients (mean age 65.8 years, 47.6% males). Results from multivariate Cox regression indicated that each additional 1 mcg/day of dietary vitamin B12 independently increased the risk of all-cause (HR, 1.07; 95% CI: 1.04-1.09, p < 0.001) and cancer-specific mortality (HR, 1.04; 95% CI, 1.02-1.06; p < 0.001). Kaplan-Meier curves indicated a higher risk of all-cause mortality with increased vitamin B12 intake (Log rank p = 0.01). Subgroup analysis suggested that higher vitamin B12 intake correlated with increased all-cause mortality risk, especially in individuals with higher protein (HR, 1.04; 95% CI, 1.02-1.06; p = 0.019) or carbohydrate intake (HR, 1.03; 95% CI, 1.01-1.05; p = 0.04). Thus, higher vitamin B12 intake correlates with increased all-cause and cancer-specific mortality in CRC patients, particularly those with higher protein or carbohydrate intake.

Proteomics-based identification of proteins in tumor-derived exosomes as candidate biomarkers for colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related death, with high morbidity worldwide. There is an urgent need to find reliable diagnostic biomarkers of CRC and explore the underlying molecular mechanisms. Exosomes are involved in intercellular communication and participate in multiple pathological processes, serving as an important part of the tumor microenvironment. AIM: To investigate the proteomic characteristics of CRC tumor-derived exosomes and to identify candidate exosomal protein markers for CRC. METHODS: In this study, 10 patients over 50 years old who were diagnosed with moderately differentiated adenocarcinoma were recruited. We paired CRC tissues and adjacent normal intestinal tissues (> 5 cm) to form the experimental and control groups. Purified exosomes were extracted separately from each tissue sample. Data-independent acquisition mass spectrometry was implemented in 8 matched samples of exosomes to explore the proteomic expression profiles, and differentially expressed proteins (DEPs) were screened by bioinformatics analysis. Promising exosomal proteins were verified using parallel reaction monitoring (PRM) analysis in 10 matched exosome samples. RESULTS: A total of 1393 proteins were identified in the CRC tissue group, 1304 proteins were identified in the adjacent tissue group, and 283 proteins were significantly differentially expressed between them. Enrichment analysis revealed that DEPs were involved in multiple biological processes related to cytoskeleton construction, cell movement and migration, immune response, tumor growth and telomere metabolism, as well as ECM-receptor interaction, focal adhesion and mTOR signaling pathways. Six differentially expressed exosomal proteins (NHP2, OLFM4, TOP1, SAMP, TAGL and TRIM28) were validated by PRM analysis and evaluated by receiver operating characteristic curve (ROC) analysis. The area under the ROC curve was 0.93, 0.96, 0.97, 0.78, 0.75, and 0.88 (P < 0.05) for NHP2, OLFM4, TOP1, SAMP, TAGL, and TRIM28, respectively, indicating their good ability to distinguish CRC tissues from adjacent intestinal tissues. CONCLUSION: In our study, comprehensive proteomic profiles were obtained for CRC tissue exosomes. Six exosomal proteins, NHP2, OLFM4, TOP1, SAMP, TAGL and TRIM28, may be promising diagnostic markers and effective therapeutic targets for CRC, but further experimental investigation is needed.

microRNA-627-5p inhibits colorectal cancer cell proliferation, migration and invasion by targeting Wnt2.

BACKGROUND: microRNA-627-5p (miR-627-5p) dysregulation has been observed in several cancer types, such as hepatocellular carcinoma, oral squamous cell carcinoma, glioblastoma multiforme, and gastric cancer. The biological function of miR-627-5p in colorectal cancer (CRC) growth and metastasis is yet unclear. AIM: To investigate the effects of miR-627-5p on the malignant biological properties of colorectal malignant tumour cells by targeting Wnt2. METHODS: The levels of miR-627-5p in colorectal tumour tissues were assessed in Gene Expression Omnibus datasets. In order to identify Wnt2 transcript expression in CRC tissues, quantitative real-time polymerase chain reaction (qRT-PCR) analysis was used. Luciferase reporter tests were used to explore whether miR-627-5p might potentially target Wnt2. Wnt2 transcript and protein levels were detected in CRC cells with high miR-627-5p expression. To learn more about how miR-627-5p affects CRC development, migration, apoptosis, and invasion, functional experiments were conducted. Cotransfection with the overexpression vector of Wnt2 and miR-627-5p mimics was utilized to verify whether overexpression of Wnt2 could cancel the impact of miR-627-5p in CRC. Western blot and qRT-PCR were conducted to investigate the effects of miR-627-5p on the Wnt/ß-catenin signalling pathway. RESULTS: miR-627-5p was notably decreased in colorectal tumour tissues, while the gene level of Wnt2 was notably upregulated. A dual luciferase reporter assay revealed that miR-627-5p specifically targets the 3'-untranslated regions of Wnt2 and miR-627-5p upregulation markedly reduced the protein and gene expression of Wnt2 in CRC cells. In vitro gain-of-function assays displayed that miR-627-5p overexpression decreased CRC cells' capabilities to invade, move, and remain viable while increasing apoptosis. Wnt2 overexpression could reverse the suppressive functions of miR-627-5p. Moreover, upregulation of miR-627-5p suppressed the transcript and protein levels of the downstream target factors in the canonical Wnt/ß-catenin signalling, such as c-myc, CD44, ß-catenin, and cyclinD1. CONCLUSION: miR-627-5p acts as a critical inhibitory factor in CRC, possibly by directly targeting Wnt2 and negatively modulating the Wnt/ß-catenin signalling, revealing that miR-627-5p could be a possible treatment target for CRC.

Age-stratified proteomic characteristics and identification of promising precise clinical treatment targets of colorectal cancer.

Colorectal cancer (CRC) is an extremely lethal disease worldwide. However, the underlying pathogenesis remains unclear. This study aimed to reveal the distinct characteristics of age-stratified CRC at the protein level and explore precise treatment targets. Patients who underwent surgical removal with pathologically confirmed CRC at China-Japan Friendship Hospital from January 2020 to October 2021 were recruited, cancer and para-carcinoma tissues (> 5 cm) were detected by mass spectrometry. Ninety-six clinical samples were collected and divided into three groups according to age: young (≤ 50 years), middle-aged (51-69 years), and old (≥ 70 years). Quantitative proteomic analysis was performed, as well as comprehensive bioinformatic analysis based on the Human Protein Atlas, Clinical Proteomic Tumor Analysis Consortium and Connectivity Map databases. The numbers of upregulated and downregulated proteins were 1315 and 560 in the young group, 757 and 311 in the old group, and 1052 and 468 in the middle-aged group, respectively. Bioinformatic analysis showed that these differentially expressed proteins had different molecular functions and participated in extensive signaling pathways. We also revealed ADH1B, ARRDC1, GATM, GTF2H4, MGME1, and LILRB2 as possible cancer-promoting molecules, which might serve as potential prognostic biomarkers and precise therapeutic targets for CRC. SIGNIFICANCE: This study comprehensively characterized the proteomic profiles of age-stratified colorectal cancer patients, focusing on the differentially expressed proteins between cancer and paracancerous tissues in different age groups, in an effort to find corresponding potential prognostic biomarkers and therapeutic targets. In addition, this study provides potentially valuable clinical small molecule inhibitory agents.

Circulating miR-627-5p and miR-199a-5p are promising diagnostic biomarkers of colorectal neoplasia.

BACKGROUND: Early detection of colorectal neoplasms, including colorectal cancers (CRCs) and advanced colorectal adenomas (AAs), is crucial to improve patient survival. Circulating microRNAs (miRNAs) in peripheral blood are emerging as noninvasive diagnostic markers for multiple cancers, but their potential for screening colorectal neoplasms remains ambiguous. AIM: To identify candidate circulating cell-free miRNAs as diagnostic biomarkers in patients with colorectal neoplasms. METHODS: The study was divided into three phases: (1) Candidate miRNAs were selected from three public miRNA datasets using differential gene expression analysis methods; (2) an independent set of serum samples from 60 CRC patients, 60 AA patients and 30 healthy controls (HCs) was included and analyzed by quantitative real-time polymerase chain reaction for miRNAs, and their diagnostic power was detected by receiver operating characteristic (ROC) analysis; and (3) the origin and function of miRNAs in cancer patients were investigated in cancer cell lines and tumor tissues. RESULTS: Based on bioinformatics analysis, miR-627-5p and miR-199a-5p were differentially expressed in both the serum and tissues of patients with colorectal neoplasms and HCs and were selected for further study. Further validation in an independent cohort revealed that both circulating miR-627-5p and miR-199a-5p were sequentially increased from HCs and AAs to CRCs. The diagnostic power of miR-672-5p yielded an area under the curve (AUC) value of 0.90, and miR-199a-5p had an AUC of 0.83 in discriminating colorectal neoplasms from HCs. A logistic integrated model combining miR-199a-5p and miR-627-5p exhibited a higher diagnostic performance than either miRNA. Additionally, the levels of serum miR-627-5p and miR-199a-5p in CRC patients were significantly lower after surgery than before surgery and the expression of both miRNAs was increased with culture time in the culture media of several CRC cell lines, suggesting that the upregulated serum expression of both miRNAs in CRC might be tumor derived. Furthermore, in vitro experiments revealed that miR-627-5p and miR-199a-5p acted as tumor suppressors in CRC cells. CONCLUSION: Serum levels of miR-199a-5p and miR-627-5p were markedly increased in patients with colorectal neoplasms and showed strong potential as minimally invasive biomarkers for the early screening of colorectal neoplasms.

Identification of circ_0000375 and circ_0011536 as novel diagnostic biomarkers of colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) imposes a tremendous burden on human health, with high morbidity and mortality. Circular ribonucleic acids (circRNAs), a new type of noncoding RNA, are considered to participate in cancer pathogenesis as microRNA (miRNA) sponges. However, the dysregulation and biological functions of circRNAs in CRC remain to be explored. AIM: To identify potential circRNA biomarkers of CRC and explore their functions in CRC carcinogenesis. METHODS: CircRNAs and miRNAs differentially expressed in CRC tissues were identified by analyzing expression profiles from the Gene Expression Omnibus (GEO) database. Circ_0000375 and circ_0011536 were selected as CRC biomarker candidates. Quantitative real-time polymerase chain reaction was utilized to evaluate the expression of these 2 circRNAs in CRC tissues, serums and cell lines. Receiver operating characteristic curves were generated to assess the diagnostic performances of these 2 circRNAs. Then, functional experiments, including cell counting kit-8, wound healing and Transwell invasion assays, were performed after the overexpression of circ_0000375 and circ_0011536 in CRC cell lines. Furthermore, candidate target miRNAs of circ_0000375 and circ_0011536 were predicted via bioinformatics analysis. The expression levels of these miRNAs were explored in CRC cell lines and tissues from GEO datasets. A luciferase reporter assay was developed to examine the interactions between circRNAs and miRNAs. Based on the target miRNAs and downstream genes, functional enrichment analyses were applied to reveal the critical signaling pathways involved in CRC carcinogenesis. RESULTS: Downregulated circ_0000375 and circ_0011536 expression was observed in CRC tissues in GSE126095, clinical CRC tissue and serum samples and CRC cell lines. The areas under the curve for circ_0000375 and circ_0011536 were 0.911 and 0.885 in CRC tissue and 0.976 and 0.982 in CRC serum, respectively. Moreover, the serum levels of these 2 circRNAs were higher in patients at 30 d postsurgery than in patients before surgery, suggesting that the serum expression of circ_0000375 and circ_0011536 is related to CRC tumorigenesis. Circ_0000375 and circ_0011536 overexpression inhibited the proliferation, migration and invasion of CRC cells. Furthermore, miR-1182 and miR-1246, which were overexpressed in CRC tissues in GSE41655, GSE49246 and GSE115513, were verified as target miRNAs of circ_0000375 and circ_0011536, respectively, by luciferase reporter assays. The downstream genes of miR-1182 and miR-1246 were enriched in some CRC-associated pathways, such as the Wnt signaling pathway. CONCLUSION: Circ_0000375 and circ_0011536 may function as tumor suppressors in CRC progression, serving as novel biomarkers for CRC diagnosis and as promising candidates for therapeutic exploration.

Delayed perforation after endoscopic resection of a colonic laterally spreading tumor: A case report and literature review.

BACKGROUND: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been widely used for the treatment of early gastrointestinal cancer. Endoscopic piecemeal mucosal resection (EPMR) is derived from the combination of EMR and ESD. Delayed perforation with peritonitis after colonic EPMR is a rare but severe complication, sometimes requiring surgery. There are some associated risk factors, including patient- (location, diameter, and presence of fibrosis) and procedure-related factors. Early recognition and timely treatment are crucial for its management. CASE SUMMARY: We report a case in which delayed perforation with peritonitis was treated using endoscopic closure. A 54-year-old man was diagnosed with a 30-mm-diameter laterally spreading tumor in the colonic hepatic curvature. Fifteen hours after endoscopic resection, peritonitis caused by delayed perforation occurred and gradually aggravated. Conservative treatment was ineffective and no obvious perforation was observed. After timely endoscopic closure, the patient was discharged on postoperative day 4. CONCLUSION: In occasion of localized peritonitis aggravating without macroscopic perforation, endoscopic closure is an effective treatment for delayed perforation with stable vital signs in the early stage.