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Colorectal cancer (CRC) is a major cause of mortality and morbidity. Gambogic acid (GA) is a promising antitumor drug for treating CRC. We aimed to elucidate its mechanism in CRC invasion/metastasis via tumor cell‐derived extracellular vesicle (EV)‐carried miR‐21. Nude mice peritoneal carcinomatosis (PC) model was subjected to GA treatment liver collection, followed by observation/counting of metastatic liver tissues/liver metastatic nodules by hematoxylin and eosin staining. miR‐21 expression in metastatic liver tissues/CD68 + CD86, CD68 + CD206 cell percentages and M2 macrophage marker CD206 level in tumor tissues/interleukin (IL)‐12 and IL‐10 levels were determined by reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR)/flow cytometry/enzyme‐linked immunosorbent assay. HT‐29 cells were treated with GA/miR‐21 mimics/negative control for 48 h. miR‐21 expression/cell proliferation/migration/invasion/apoptosis were assessed by RT‐qPCR/cell counting kit‐8/scratch assay/transwell assay/flow cytometry. EVs were extracted from HT‐29 cells and identified by transmission electron microscope/nanoparticle tracking analysis/Western blot. IL‐4/IL‐13‐induced macrophages/PC nude mice were treated with GA and EVs, with the internalization of EVs by macrophages assessed through the uptake test. After intraperitoneal injection of GA, PC nude mice exhibited decreased tumor cell density/irregular cell number/liver metastatic nodule number/miR‐21 expression, and CRC cells manifested reduced CD68 + CD206 cells/IL‐10/miR‐21/proliferation/migration/invasion and increased CD68 + CD86 cells/IL‐12/apoptosis, while these trends were opposite after miR‐21 overexpression, implying that GA curbed CRC/cell invasion/metastasis and macrophage polarization by diminishing miR‐21 levels. miR‐21 was encapsulated in HT‐29 cell‐derived EVs. M2 polarization elevated CD206 cells/IL‐10, which were decreased by simultaneous GA treatment. EVs could be uptaken by macrophages. CRC cell‐EV‐miR‐21 annulled the suppression effects of GA on macrophage M2 polarization. GA suppressed macrophage M2 polarization by lessening tumor cell derived‐EV‐shuttled miR‐21, thereby weakening CRC invasion/metastasis. [ABSTRACT FROM AUTHOR]

Purpose: Exploring the expression and prognosis of mismatch repair proteins and PD-L1 in colorectal cancer.Patients and Methods: A total of 272 patients with surgically resected CRC were enrolled in the study from January 2018 to May 2022 at Nanjing Drum Tower Hospital (The Affiliated Hospital of Nanjing University Medical School). Surgically resected samples were collected from patients along with general, clinicopathological, and imaging data for each patient. Immunohistochemistry (IHC) was used to detect expression of MSH2, MSH6, MLH1, and PMS2 proteins in tumor tissue. X-squared (X2) testing was performed to investigate the correlation between expression of MMR proteins and PD-L1 in CRC tumor tissues and clinicopathological characteristics. Correlation analysis was also used to compare the deletion of four MMR proteins in CRC tumor tissues. A survival curve and Log rank test were used to investigate the relationship between the expression of MMR proteins and PD-L1 with regard to CRC patient prognosis and survival.Results: MMR protein expression deletion was correlated with tumor location, the degree of tissue differentiation, and TNM stage (P< 0.05). PD-L1 expression was correlated with TNM stage (P< 0.05). Correlation analysis of deletion of MMR protein isoform expression found that PMS2 deletion was significantly correlated with MLH1 deletion (P< 0.05). Similarly, MSH2 deletion was significantly correlated with MSH6 deletion (P< 0.05). PMS2 deletion was also found to be correlated with PD-L1 expression (P< 0.05). Progression-free survival was found to be significantly longer in mismatch repair-proficient (pMMR) patients compared with mismatch repair-deficient (dMMR) patients.Conclusion: Deletion of MMR proteins and expression of PD-L1 are closely related to clinicopathological characteristics and overall prognosis of CRC patients. This suggests the relevance of MMR and PD-L1 as potential biomarkers for treatment of CRC patients. [ABSTRACT FROM AUTHOR]

Microsatellite instability (MSI) has emerged as an important predictor of sensitivity for immunotherapy-based strategies. β-2-Microglobulin (B2M) contains microsatellites within the coding regions and is prone to somatic changes in MSI/mismatch repair deficiency (MSI/dMMR) tumors. To delineate prevalence and associations of B2M mutations in MSI-H/dMMR cancers, we investigated the mutational profile of B2M and clinical and pathological features in gastric cancer (GC), colorectal cancer (CRC), and endometrial cancer (EC) with a high incidence of microsatellite instability-high (MSI-H)/dMMR. Formalin-fixed paraffin-embedded (FFPE) tumor tissues along with matched normal tissues were collected from 108 MSI/dMMR patients with GC, CRC, and EC. Genomic profiling of tissue and blood samples were assessed next-generation sequencing (NGS). Immunohistochemistry (IHC) was used to examine the presence or absence of B2M protein. Alternations in the exonic microsatellite regions of B2M were observed at various but high frequencies (57.5% in CRC, 23.9% in GC, and 13.6% in EC) and in different forms. NGS assay revealed that genes involved in chromatin regulation, the PI3K pathway, the WNT pathway, and mismatch repair were extensively altered in the MSI-H cohort. Signature 6 and 26, 2 of 4 mutational signatures associated with defective DNA mismatch repair, featured with high numbers of small insertion/deletions (INDEL) dominated in all 3 types of cancer. Alternations in the exonic microsatellite regions of B2M were observed at various but high frequencies (57.5% in CRC, 23.9% in GC, and 13.6% in EC) and in different forms. Tumor mutational burden (TMB) was significantly higher in the patients carrying MSI-H/dMMR tumors with B2M mutation than that in patients with wild-type B2M (P =.026).The frame shift alteration occurring at the exonic microsatellite sties caused loss of function of B2M gene. In addition, a case with CRC carrying indels in B2M gene resisted the ICI treatment was reported. In conclusion, patients carrying MSI-H/dMMR tumors with B2M mutation showed significantly higher TMB. Prescription of ICIs should be thoroughly evaluated for these patients. [ABSTRACT FROM AUTHOR]

The stability and release of iRGD-modified RBCm nanoparticles loaded with Jug and Oxa (RBCm-(Jug, Oxa)-iRGD-NPs) were evaluated by Dynamic light scattering (DLS) and ultraviolet spectrophotometer, respectively. The current study demonstrated that RBCm-(Jug, Oxa)-iRGD-NPs had a drug-release profile similar to RBCm-(Jug, Oxa)-NPs, but were more stable. Keywords: Juglone; Oxaliplatin; nanoparticles; iRGD; colorectal cancer EN Juglone Oxaliplatin nanoparticles iRGD colorectal cancer 1301 1316 16 01/25/22 20220201 NES 220201 Poor solubility and non-specific biological distribution are critical obstacles for applying Juglone (Jug) into clinical practice. [Extracted from the article]

Background: HLX04 is a proposed biosimilar of bevacizumab. Objective: This phase III study aimed to evaluate the efficacy, safety, and immunogenicity of HLX04 compared with reference bevacizumab in combination with XELOX or mFOLFOX6 as first-line treatment for recurrent/metastatic colorectal cancer (CRC). Methods: In this double-blind, parallel-group study, patients were randomized 1:1 to receive HLX04 or bevacizumab (7.5 mg/kg every 3 weeks when combined with XELOX; 5 mg/kg every 2 weeks when combined with mFOLFOX6). The primary endpoint was progression-free survival rate at week 36 (PFSR36w) per Response Evaluation Criteria in Solid Tumors (RECIST v1.1). Prespecified equivalence margins of PFSR36w were set as − 11 to 15% (rate difference) and 0.8 to 1.25 (rate ratio). Secondary endpoints included efficacy, safety, immunogenicity, and pharmacokinetics. Results: A total of 677 patients were randomized (HLX04 n = 340; bevacizumab n = 337) between April 2018 and April 2020. PFSR36w was 46.4% (95% confidence interval [CI] 41.1–51.8) with HLX04 and 50.7% (95% CI 45.4–56.1) with bevacizumab. The rate difference (− 4.2%; 90% CI − 10.6 to 2.1) and rate ratio (0.92; 90% CI 0.80–1.05) both fell within the prespecified equivalence margins. No notable differences were observed between treatment groups in any efficacy endpoints or their subgroup analyses. Safety, immunogenicity, and pharmacokinetic profiles were comparable between the two treatment groups. Conclusions: HLX04 demonstrated equivalent efficacy with similar safety and immunogenicity profiles to reference bevacizumab among patients with recurrent/metastatic CRC, thus offering an alternative treatment option to patients. Trial registration: Chinadrugtrials.org.cn, CTR20171503 (18 March 2018); ClinicalTrials.gov, NCT03511963 (30 April 2018). Plain Language Summary: Colorectal cancer (CRC) is the third most common cancer worldwide. Approximately 20% of patients with CRC have metastases at their first visit. Bevacizumab is a biologic antibody approved in many countries for the treatment of metastatic CRC. However, high treatment costs significantly limit patient access to bevacizumab. Therefore, HLX04, a potential bevacizumab biosimilar, which is almost identical to bevacizumab but less expensive and more accessible, has been developed. This randomized clinical trial was designed to evaluate the efficacy (ability of a drug to produce the desired treatment effects), safety, and immunogenicity (ability of a drug to induce immune response that would affect its efficacy and safety) of HLX04 compared with the reference bevacizumab in patients with recurrent/metastatic CRC. Efficacy of the tested drug was evaluated by comparing the proportion of patients without disease progression or death at week 36 (PFSR36w). Safety was monitored using adverse events and other clinical evaluations. Immunogenicity was assessed by the incidence of antidrug antibodies. Of the 677 patients enrolled in the study, 340 received HLX04 and 337 received bevacizumab. Statistical analyses showed that HLX04 was equivalent to bevacizumab in efficacy evaluations (the difference in PFSR36w between the two treatment groups fell within the prespecified "equivalence margins"). Moreover, the two treatments were similar with respect to safety and immunogenicity evaluations. In summary, patients responded equally well to HLX04 and bevacizumab, supporting the development of HLX04 as a proposed biosimilar to bevacizumab for patients with recurrent/metastatic CRC. [ABSTRACT FROM AUTHOR]

Deleterious mutations in APC gene cause the autosomal dominant familial adenomatous polyposis (FAP) which is typically characterized by the occurrence of hundreds to thousands of colorectal adenomas that eventually lead to colorectal cancers (CRCs). BRCA1/2 are the two major susceptibility genes for breast and ovarian cancers. Here, we reported a coinheritance of mutations in APC and BRCA1 genes in a 20-year-old CRC patient with typical clinical features for FAP. Multiple relatives in the family of the patient were affected by colorectal and other cancers. Next-generation sequencing analysis using a panel consisting of 53 hereditary cancer related genes revealed a maternally inherited APC (exon15cn_del) mutation and a paternally inherited BRAC1 (p.lle1824AspfsX3) mutation. This is the first coexistence of APC and BRCA1 mutations in a CRC patient with the mutation inheritance pattern comprehensively characterized in the family. The patient underwent a colonoscopy and a subtotal colectomy and was subsequently diagnosed with colonic adenocarcinomas accompanied with hundreds of tubulovillous adenomas. The case reveals the scenario where two disease-causing mutations of different hereditary tumor syndromes coexist, and illustrates the importance of evaluating detailed family history and performing a multiple-gene panel test in patients with hereditary cancer. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have been shown to play important roles in various tumors including colorectal cancer (CRC). Here, we obtained data from RNA-sequencing analysis using 3 paired of CRC tissues and corresponding normal tissues. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, the biological functions of these dysregulated genes were identified. Moreover, we analyzed the expression levels of lncRNA PGM5-AS1 and B3GALT5-AS1 by quantitative real-time PCR (qRT-PCR) assay. To evaluate the accuracy of the lncRNA-mRNA co-expression network we built, we also detected PGM5 expression and analyzed the relationship between PGM5-AS1 and PGM5 in CRC. In addition, we explored the potential function of PGM5-AS1 in vitro and in vivo. In conclusion, we identified dysregulated lncRNAs and constructed the lncRNA-mRNA co-expression network in CRC. Then, we showed that the expression levels of PGM5-AS1, B3GALT5-AS1 and PGM5 were significantly downregulated in CRC tissues compared with corresponding normal tissues. Besides, PGM5-AS1 expression was positively associated with PGM5 expression. These findings were consistent with our RNA-sequencing data. Functionally, overexpression of PGM5-AS1 could induce cell apoptosis and cell cycle arrest in CRC. Animal study indicated that PGM5-AS1 overexpression inhibited CRC growth in vivo. This work provides dysregulated lncRNAs as candidates for further study in CRC. The lncRNA-mRNA co-expression network brings novel insights into further function research. More importantly, PGM5-AS1 is a critical tumor suppressor in CRC. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs are widely acknowledged as a group of regulatory factors in various diseases, especially in cancers. KCNQ1 overlapping transcript 1 (KCNQ1OT1) has been reported as oncogene in human cancers. However, the role of KCNQ1OT1 in colorectal cancer (CRC) has not been fully explained. Based on the database analysis, KCNQ1OT1 was highly expressed in CRC samples and predicted the poor prognosis for CRC patients. Functional experiments revealed that KCNQ1OT1 knockdown negatively affected the proliferation, migration and epithelial-mesenchymal transition (EMT) in CRC cells. Moreover, we identified the cytoplasmic localization of KCNQ1OT1 in CRC cells, indicating the post-transcriptional regulation of KCNQ1OT1 on gene expression. Mechanism experiments including RNA Immunoprecipitation (RIP) assay and dual luciferase reporter assays verified that KCNQ1OT1 acted as a competing endogenous RNA (ceRNA) in CRC by sponging microRNA-217 (miR-217) to up-regulate the expression of zinc finger E-box binding homeobox 1 (ZEB1). Further mechanism investigation revealed that ZEB1 enhanced the transcription activity of KCNQ1OT1 by acting as a transcription activator. Finally, rescue assays were designed to demonstrate the effect of KCNQ1OT1-miR-217-ZEB1 feedback loop on proliferation, migration, and EMT of CRC cells. In brief, our research findings revealed that ZEB1-induced upregulation of KCNQ1OT1 improved the proliferation, migration and EMT formation of CRC cells via regulation of miR-217/ZEB1 axis. [ABSTRACT FROM AUTHOR]

MicroRNAs (miR) are important in various crucial cell processes including proliferation, migration and invasion. Dysregulation of miRNAs have been increasingly reported to contribute to colorectal cancer. However, the detailed biological function and potential mechanisms of miR‑1273g‑3p in colorectal cancer remain poorly understood. The expression levels of miR‑1273g‑3p in human colorectal cancer LoVo cell lines were detected via reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). The target genes of miR‑1273g‑3p were predicted by bioinformatics and verified by a luciferase reporter assay, RT‑qPCR and western blotting. The MTT, wound‑healing and Transwell assays were used to examine the biological functions of miR‑1273g‑3p in LoVo cells. The potential molecular mechanisms of miR‑1273g‑3p on LoVo cell proliferation, migration and invasion was detected by western blotting. The results of the present study demonstrated that miR‑1273g‑3p expression was extensively upregulated in LoVo cells compared with the normal colon epithelial NCM460 cell line. Further studies indicated that miR‑1273g‑3p inhibitor significantly suppressed LoVo cell proliferation, migration and invasion compared with inhibitor control. Following this, the cannabinoid receptor 1 (CNR1) was identified as a direct target gene of miR‑1273g‑3p. Knockdown of CNR1 restored the phenotypes of LoVo cells transfected with miR‑1273g‑3p inhibitor. Furthermore, the potential molecular mechanism of miR‑1273g‑3p on LoVo cell proliferation, migration and invasion may be mediated by activating the Erb‑B2 receptor tyrosine kinase 4 (ERBB4)/phosphoinositide‑3‑kinase regulatory subunit 3 (PIK3R3)/mechanistic target of rapamycin (mTOR)/S6 kinase 2 (S6K2) signaling pathway. These observations indicated that miR‑1273g‑3p promoted the proliferation, migration and invasion of LoVo cells via CNR1, and this may have occurred through activation of the ERBB4/PIK3R3/mTOR/S6K2 signaling pathway, suggesting that miR‑1273g‑3p may serve as a novel therapeutic target for the effective treatment of colorectal cancer. [ABSTRACT FROM AUTHOR]