Colorectal cancer is considered one of the major malignancies that threaten the lives and health of people around the world. Patients with CRC are prone to post-operative local recurrence or metastasis, and some patients are advanced at the time of diagnosis and have no chance for complete surgical resection. These factors make chemotherapy an indispensable and important tool in treating CRC. However, the complex composition of the tumor microenvironment and the interaction of cellular and interstitial components constitute a tumor tissue with high cell density, dense extracellular matrix, and high osmotic pressure, inevitably preventing chemotherapeutic drugs from entering and acting on tumor cells. As a result, a novel drug carrier system with targeted nanoparticles has been applied to tumor therapy. It can change the physicochemical properties of drugs, facilitate the crossing of drug molecules through physiological and pathological tissue barriers, and increase the local concentration of nanomedicines at lesion sites. In addition to improving drug efficacy, targeted nanoparticles also reduce side effects, enabling safer and more effective disease diagnosis and treatment and improving bioavailability. In this review, we discuss the mechanisms by which infiltrating cells and other stromal components of the tumor microenvironment comprise barriers to chemotherapy in colorectal cancer. The research and application of targeted nanoparticles in CRC treatment are also classified.

Background: Charged multivesicular body protein 7 is briefly referred to as CHMP7, and it plays a significant role in the endosomal sorting pathway. CHMP7 can form a complex with ESCRTIII to jointly complete the process of contraction, shear bud neck and final membrane shedding. Methods: TCGA, GEO and CPTAC were chosen for the analysis of the role of CHMP7 in pan-cancer. Role of CHMP7 in pan-cancer was analyzed using R software and tools such as TIMER, GEPIA, UALCAN, String and DiseaseMeth. It includes differential expression analysis of CHMP7, survival analysis, genetic variation analysis, DNA methylation analysis, post-translationally modified protein phosphorylation analysis and functional enrichment analysis. Results: CHMP7 presents low expression in the majority of tumor tissues and the prognosis is poor in the low expression group. The common gene mutation in CHMP7 is deep deletion, which may lead to frameshift mutations, resulting in a poor prognosis. Functional alterations due to DNA methylation and post-transcriptional protein modifications may be closely associated with tumors. GO analysis revealed that CHMP7-related genes are involved in the composition of the various ESCRT complexes. In terms of molecular function, they mainly bind to GTP, exert GTPase activity and promote multivesicular bodies assembly. In the KEGG enrichment analysis, the main pathways expressed by CHMP7 and related genes were endocytosis, gap junction and phagosome. Conclusion: Pan-cancer analysis showed that CHMP7 expression was statistically correlated with clinical prognosis, DNA methylation, protein phosphorylation and immune cell infiltration, which may provide new ideas or targets for the diagnosis or treatment.

Background: Circular RNAs (circRNAs) represent a distinct class of non-coding RNAs that have attracted substantial research attention in recent years. We identified a novel circRNA derived from golgi glycoprotein 1 mRNA (circ_GLG1), the role of which is unknown in colorectal cancer (CRC). The purpose of this study was to explore the potential roles and mechanisms of circ_GLG1 in CRC. Materials and Methods: Quantitative reverse transcriptase-polymerase chain reaction analysis was performed to quantify circ_GLG1 expression in 40 pairs of CRC tissues and adjacent normal tissues as well as CRC cell lines. DLD1 CRC cells were transfected with a small-interfering RNA against circ_GLG1, after which cell proliferation, viability, invasion, and migration were measured through cell counting kit-8 colony-formation, transwell, and wound-healing assays, respectively. Dual-luciferase reporter assays were performed to explore the binding sites among circ_GLG1, miR-622, and Kirsten rat sarcoma (KRAS) transcripts. KRAS protein expression was detected using Western blot analysis. Results: Circ_GLG1 expression was significantly higher in CRC tissues than in adjacent normal tissues. Knocking down circ_GLG1 in DLD1 cells inhibited tumor cell viability, proliferation, invasion, and migration, and these effects were reversed by co-transfecting an miR-622 inhibitor. Circ_GLG1 promoted KRAS expression at both the mRNA and protein levels by acting as an miR-622 sponge. Dual-luciferase reporter assays demonstrated that miR-622 interacted with circ_GLG1 and KRAS mRNA. Conclusion: Our study revealed the role of the circ_GLG1–miR-622–KRAS axis in CRC. Moreover, our findings provide insight into the molecular mechanism of circ_GLG1 in CRC and suggest potential new biomarkers for diagnosing this disease.

Background: Colorectal cancer (CRC), the third most commonly diagnosed malignant carcinoma and the third most common cause of carcinoma-related mortality, continues to be a major international health problem. And approximately 33% of patients suffer from recurrence after radical surgery. Free malignant cell implanting in the peritoneum is generally accepted as one of the main reasons of such outcome. We did this present clinical study with the aim of evaluating the effects and safety of intraoperative intraperitoneal chemotherapy (IOC) on patients suffering from colorectal cancer, with hoping to find a novel, effective, and available approach to deal with malignant cell implanting during surgeries. Methods: In total, 391 patients who went through colorectal radical surgery were considered eligible between June 1, 2017, and December 31, 2018. 220 patients were treated with surgery without IOC, while other 171 patients received surgery plus IOC. Clinical characteristics, operative findings, postoperative short-term outcomes, disease-free survival (DFS), and overall survival (OS) were compared between these above 2 groups in the selected population. Result: The present research included 391 patients (251 men and 140 women) who underwent surgery without IOC (n = 171) or surgery plus IOC (n = 220), with a mean (SD) age of 60.4 (9.7) years in the surgery without IOC group and 60.6 (8.7) in the surgery plus IOC group (P=.85). No significant differences were witnessed between the two groups in surgery-related information and postoperative complications. It is worth noting that IOC independent of other factors was associated with a favor prognosis in CRC patients with stage II/III (HR 0.50, 95%CI 0.30–0.82, P=.006). Moreover, for patients with stage II colorectal carcinoma, DFS did not differ between two groups (P=.553, Kaplan-Meier log-rank), and OS was no exception. In stage III CRC patients, the estimated DFS rate for patients receiving IOC was 82.2% and patients without IOC was 66.4% after 3 years, which demonstrated that IOC was associated with a favorable prognosis in stage III patients (P=.012, Kaplan-Meier log-rank). Furthermore, the differences were still remained between the two groups when considering the influence about postoperative chemotherapy (P=.014, Kaplan-Meier log-rank). IOC can also significantly improve patients’ overall survival whether they get treatment with POC (P=.006, Kaplan-Meier log-rank; P=.025, Kaplan-Meier log-rank). Conclusions: In the present study, we have found that surgery plus IOC generated a favorable prognosis for stage III CRC patients but not stage II without any side-effects when the dosage of lobaplatin was 0.1g/L. As a new, safe, and simple procedure, IOC therapy is easily performed—and does not require any special devices or techniques. Thus, IOC is a promising and exciting therapeutic strategy for patients with CRC.

Colon cancer is a common malignant disease of the gastrointestinal tract and usually occurs at the junction of the rectum and sigmoid colon. Lymphatic and hematogenous metastases occur frequently in colon cancer and the most common metastatic sites include the liver, lung, peritoneum, bone, and lymph nodes. As a manifestation of advanced tumor spread and metastasis, soft tissue metastasis, especially skeletal muscle metastasis with bone metaplasia caused by colon cancer, is rare, accounting for less than 1% of metastases. A 43-year-old male patient developed skeletal muscle metastasis with bone metaplasia of the right proximal thigh 5 mo after colon cancer was diagnosed. The patient was admitted to the hospital because of pain caused by a local mass on his right thigh. Positron emission tomography-computed tomography showed many enlarged lymph nodes around the abdominal aorta but no signs of lung or liver metastases. Color ultrasound revealed a mass located in the skeletal muscle and the results of histological biopsy revealed a poorly differentiated adenocarcinoma suspected to be distant metastases from colon cancer. Immunohistochemistry showed small woven bone components that were considered to be ossified. This case reminds us that for patients with advanced colorectal tumors, we should be alert to the possibility of unconventional metastasis.

Background: As a common cancer with high incidence rate and mortality, colorectal cancer (CRC) is seriously threatening human health. S-nitrosylation (SNO) proteins mediated by nitric oxide (NO) has important implications in the genesis, progression, and apoptosis of CRC. It’s worth noting that the SNO proteins also play an important role in the tumor endocrine and metabolic pathways of CRC.Materials and methods: In this study, the protein extracts of human tissues and cell lines were treated by biotin switch technology and magnetic beads enrichment. The proteomic results of endogenous and potential SNO proteins were analyzed by mass spectrometry (MS). Through the comparison and analysis of MS results, Gene Ontology (GO) analysis, and literatures, some endogenous and potential SNO proteins were identified in CRC, which were closely related to the tumor endocrine and metabolic pathways, the apoptotic signaling pathways, protein maturation, and other biological processes of the proliferation and apoptosis of CRC cells.Results: A total of 19 proteins containing potential or endogenous SNO sites were detected in both human cancer tissue and SW 480 cells. Through the cross validation of MS results, GO analysis, and literatures, several SNO proteins were identified frequently in CRC, such as the actin, cytoplasmic 1 (ACTB), peroxiredoxin-4 (PRDX4), protein S100A8 (S100A8), pyruvate kinase PKM (PKM), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which were closely related to the tumor endocrine and metabolic pathways and the apoptotic signaling pathways of CRC.Conclusion: Different CRC cells and tissues contained potential and endogenous SNO modified proteins. In addition, some SNO proteins could participate in the proliferation, metastasis and apoptosis of CRC by regulating the tumor endocrine and metabolic pathways.