Are Colon and Rectal Cancer Two Different Tumor Entities? A Proposal to Abandon the Term Colorectal Cancer. Int J Mol Sci. 2018;19. [PMID: 30200215 PMCID: PMC6165083 DOI: 10.3390/ijms19092577]

Gastrointestinal cancer and occupational diesel exhaust exposure: a meta-analysis of cohort studies

BACKGROUND

Diesel exhaust exposure and cancer other than the lungs have been limitedly investigated.

AIMS

To conduct a systematic review and meta-analysis on the association between occupational exposure to diesel exhaust and gastrointestinal cancers.

METHODS

Two researchers performed a systematic literature review to identify all cohort studies on occupational exposure to diesel exhaust and risk of cancers other than lung. Of the 30 retained studies, 10 reported risk estimates for oesophageal, 18 on gastric, 15 on colon and 14 on rectal cancer. We performed random-effects meta-analyses to calculate summary relative risks (RRs) and 95% confidence intervals (CIs) for ever-exposure to diesel exhaust.

RESULTS

We calculated summary RR = 1.08 (95% CI 0.97-1.21, P heterogeneity = 0.06) for oesophageal, 1.06 (95% CI 0.99-1.14, P < 0.001) for gastric, 0.98 (95% CI 0.96-1.00, P = 0.453) for colon, and RR = 1.04 (95% CI 0.97-1.11, P = 0.013) for rectal cancer. Drivers showed an association with oesophageal (RR = 1.26, 95% CI 0.99-1.62), gastric (RR = 1.20, 95% CI 0.91-1.59) and rectal cancer (RR = 1.41, 95% CI 1.13-1.75); machine operators with oesophageal (RR = 1.09, 95% CI 1.00-1.20) and gastric (RR = 1.15, 95% CI 1.10-1.20) and handlers with oesophageal cancer (RR = 1.95, 95% CI 1.23-3.09). Studies from Europe revealed an association with gastric cancer while those from North America did not (P < 0.05). No difference was found by quality score except for gastric cancer, where high-quality studies but not low-quality ones showed increased risk (P heterogeneity = 0.04). There was no evidence of publication bias.

CONCLUSIONS

An increased but insignificant risk of oesophageal, gastric and rectal, but not colon cancer, was suggested in workers exposed to diesel exhaust. Residual confounding cannot be excluded.

Diurnal timing of physical activity and risk of colorectal cancer in the UK Biobank

BACKGROUND

Physical activity reduces colorectal cancer risk, yet the diurnal timing of physical activity in colorectal cancer etiology remains unclear.

METHODS

This study used 24-h accelerometry time series from UK Biobank participants aged 42 to 79 years to derive circadian physical activity patterns using functional principal component analysis. Multivariable Cox proportional hazard models were used to examine associations with colorectal cancer risk.

RESULTS

Among 86,252 participants (56% women), 529 colorectal cancer cases occurred during a median 5.3-year follow-up. We identified four physical activity patterns that explained almost 100% of the data variability during the day. A pattern of continuous day-long activity was inversely associated with colorectal cancer risk (hazard ratio (HR) = 0.94, 95% confidence interval (CI) = 0.89-0.99). A second pattern of late-day activity was suggestively inversely related to risk (HR = 0.93, 95% CI = 0.85-1.02). A third pattern of early- plus late-day activity was associated with decreased risk (HR = 0.89, 95% CI = 0.80-0.99). A fourth pattern of mid-day plus night-time activity showed no relation (HR = 1.02, 95% CI = 0.88-1.19). Our results were consistent across various sensitivity analyses, including the restriction to never smokers, the exclusion of the first 2 years of follow-up, and the adjustment for shift work.

CONCLUSIONS

A pattern of early- plus late-day activity is related to reduced colorectal cancer risk, beyond the benefits of overall activity. Further research is needed to confirm the role of activity timing in colorectal cancer prevention.

B7H3 Immune Checkpoint Overexpression Is Associated with Decreased Complete Response Rates to Neoadjuvant Therapy in Locally Advanced Rectal Cancer

BACKGROUND AND OBJECTIVES

Rectal cancer accounts for approximately one-third of colorectal cancers, with over 340,000 deaths globally in 2022. Despite advancements in treatment, the five-year overall survival for locally advanced rectal cancer (LARC) remains at 74%, with significant morbidity. B7H3 (CD276), an immune checkpoint protein, plays a role in tumor progression and resistance to therapy, and correlates with poor prognosis in various cancers, including colorectal cancer. This study aims to evaluate the expression of B7H3 in LARC and its impact on overall complete response (oCR) rates to neoadjuvant therapy.

METHODS

A retrospective study was conducted on 60 patients with LARC who received neoadjuvant chemoradiation (nCRT) followed by total mesorectal excision (TME). B7H3 expression was assessed using immunohistochemistry on surgical specimens. Expression levels were categorized as high or low based on a composite score, and their association with oCR rates was analyzed.

RESULTS

High B7H3 expression was observed in 60% of patients, with 73.5% showing expression in more than 50% of tumor cells. Patients who achieved oCR had significantly lower B7H3 expression compared to those with residual disease (p < 0.001). No nuclear expression of B7H3 was detected. No significant correlation was found between B7H3 expression and other clinicopathological variables, except for a higher likelihood of non-restorative surgery in patients with elevated B7H3 levels (p = 0.049). Mucinous adenocarcinoma had high expression of B7H3.

CONCLUSIONS

Elevated B7H3 expression is associated with reduced oCR rates in LARC, highlighting its potential role as a prognostic biomarker. Further studies with larger cohorts are warranted to validate these findings and explore B7H3-targeted therapies as a treatment strategy for LARC.

The impact of preoperative treatments on the immune environment of rectal cancer

To improve local disease control, the use of preoperative radiotherapy either alone or combined with chemotherapy has become standard practice in rectal cancer, but it is unclear how these treatments modify the antitumoral immune response. We aimed to evaluate tumor histopathologic features and the prognostic effect of host immune response in rectal cancer with variable treatment modalities. Ninety-five rectal cancers with short-course radiotherapy (SRT), 97 with long-course chemoradiotherapy (CRT), and 154 without preoperative treatments, were evaluated for histopathologic features including Crohn's-like reaction (CLR). CD3+ and CD8+ immunohistochemistry and tumor cells were analyzed from tumor tissue microarray samples to calculate T-cell densities and G-cross function values to estimate cancer cell-T-cell co-localization (proximity score). We found that lymphocyte densities were diminished after SRT, but CLR was scarcer after CRT. Proximity score and CLR density were prognostic for survival in cancer without preoperative treatments and could be combined into an enhanced prognostic score (immune grade). In the irradiated tumors, CLR density remained prognostic while the impact of T-cell infiltration was insufficient alone. In multivariable analysis, the immune grade proved to be an independent prognostic factor for survival. In conclusion, the immune contexture of rectal cancer harbors prognostic significance even after preoperative radiotherapy.

Different Metabolic Associations of Hepatitis C With Colon and Rectal Cancers: A 9-Year Nationwide Population-Based Cohort Study

BACKGROUND

Whether HCV infection is associated with colorectal cancer (CRC) development remains inconclusive.

METHODS

A nationwide population-based cohort study of the Taiwan National Health Insurance Research Database was conducted.

RESULTS

From 2003 to 2012, 1:2:2 propensity score-matched HCV-treated [interferon-based therapy ≥ 6 months, surveys for CRC (n = 9017), colon cancer (CC) (n = 9,022) and rectal cancer (RC) (n = 9,033), HCV-untreated and HCV-uninfected cohorts CRC (n = 18034), CC (n = 18,044) and RC (n = 18,066) were enrolled. The HCV-uninfected cohort had the lowest cumulative incidence of CRC (0.117%; 95% CI: 0.062%-0.207%), whereas the HCV-treated (0.966%; 0.375-2.122%) and HCV-untreated (0.807%; 0.485%-1.280%) cohorts had similar incidences (P = .0662); HCV infection [reference: HCV-untreated cohort, HCV-treated: hazard ratio (HR): 0.598; 95% CI HR: 0.337-1.059; HCV-uninfected: 0.250; 0.138-0.456] and age ≥ 49 years (3.128;1.751-5.59) were associated with CRC development. The HCV-untreated cohort had the highest cumulative incidence of CC (0.883%; 0.371-1.839%), while HCV-treated (0.478%; 0.110-1.518%) and HCV-uninfected cohorts (0.147%; 0.071-0.284%) had similar incidences (P = .4853); HCV infection (HCV-treated: 0.474; 0.232-0.971; HCV-uninfected: 0.338; 0.184-0.62), male sex (2.18; 1.301-3.654), age≥ 49 years (4.818; 2.123-10.936) and diabetes (1.983; 1.205-3.262) were associated with CC development. A higher RC cumulative incidence was noted in the HCV-untreated cohort (0.332%; 0.151-0.664%) than in the HCV-uninfected cohort (0.116%; 0.054-0.232%) (P = .0352); HCV infection (HCV-treated: 0.691; 0.295-1.617; HCV-uninfected: 0.424; 0.207-0.867), age ≥ 49 years (3.745, 1.576-8.898) and stroke (3.162; 1.366-7.322) were associated with RC development.

CONCLUSIONS

The baseline associations were HCV infection and age ≥ 49 years with CRC; male sex and diabetes with CC; and stroke with RC. Anti-HCV therapy might reverse the risk of HCV-related CC but not RC.

Associations between low- and high-fat dairy intake and recurrence risk in people with stage I-III colorectal cancer differ by sex and primary tumour location

We previously demonstrated that intake of low-fat dairy, but not high-fat dairy, was associated with a decreased colorectal cancer (CRC) recurrence risk. These risks, however, may differ by sex, primary tumour location, and disease stage. Combining data from two similar prospective cohort studies of people with stage I-III CRC enabled these subgroup analyses. Participants completed a food frequency questionnaire at diagnosis (n = 2283). We examined associations between low- and high-fat dairy intake and recurrence risk using multivariable Cox proportional hazard models, stratified by sex, and primary tumour location (colon and rectum), and disease stage (I/II and III). Upper quartiles were compared to lower quartiles of intake, and recurrence was defined as a locoregional recurrence and/or metastasis. During a median follow-up of 5.0 years, 331 recurrences were detected. A higher intake of low-fat dairy was associated with a reduced risk of recurrence (hazard ratio [HR]: 0.60, 95% confidence interval [CI]: 0.43-0.83), which seemed more pronounced in men (HR: 0.51, 95% CI: 0.34-0.77) than in women (HR: 0.84, 95% CI: 0.47-1.49). A higher intake of high-fat dairy was associated with an increased risk of recurrence in participants with colon cancer (HR: 1.60, 95% CI: 1.03-2.50), but not rectal cancer (HR: 0.88, 95% CI: 0.54-1.45). No differences in associations were observed between strata of disease stage. Concluding, our findings imply that dietary advice regarding low-fat dairy intake may be especially important for men with CRC, and that dietary advice regarding high-fat dairy intake may be specifically important in people with colon cancer.

Emergency Resection for Colonic Cancer Has an Independent and Unfavorable Effect on Long-Term Oncologic Outcome

BACKGROUND

Long-term outcomes in patients undergoing emergency versus elective resection for colorectal cancer (CRC) remain controversial. This study aims to assess short- and long-term outcomes of emergency versus elective CRC surgery.

METHODS

In this single-center retrospective cohort study, patients undergoing emergency or elective colonic resections for CRC from January 2013 to December 2017 were included. Primary outcome was long-term survival. As secondary outcomes, we sought to analyze potential differences on postoperative morbidity and concerning the oncological standard of surgical resection. The Kaplan-Meier curves and Cox proportional hazard model were used to compare survival between the groups.

RESULTS

Overall, 225 CRC patients were included. Of these 192 (85.3%) had an elective and 33 (14.7%) an emergency operation. Emergency indications were due to obstruction, perforation, or bleeding. Patients in the emergency group had higher ASA score (p = 0.023), higher Charlsson comorbidity index (CCI, p = 0.012), and were older than those in the elective group, with median age 70 (IQR 63-79) years and 78 (IQR 68-83) years, for elective and emergency, respectively (p = 0.020). No other preoperative differences were observed. Patients in the emergency group experienced significantly more major complications (12.1% vs. 3.6%, p = 0.037), more anastomotic leakage (12.1% vs. 1.6%, p = 0.001), need for reoperation (12.1% vs. 3.1%, p = 0.021), and postoperative mortality (2 patients vs. 0, p < 0.001). No differences in terms of final pathological stage, nor in accuracy of lymphadenectomy were observed. Overall survival was significantly worse in case of emergency operation, with estimated median 41 months vs. not reached in elective cases (p < 0.001). At the multivariate analysis, emergency operation was confirmed as independent unfavorable determinant of survival (with hazard rate HR = 1.97, p = 0.028), together with age (HR = 1.05, p < 0.001), postoperative major morbidity (HR = 3.18, p = 0.012), advanced stage (HR = 5.85, p < 0.001), and need for transfusion (HR = 2.10, p = 0.049).

CONCLUSION

Postoperative morbidity and mortality were increased in emergency versus elective CRC resections. Despite no significant differences in terms of accuracy of resection and pathological stages, overall survival was significantly worse in patients who underwent emergency procedure, and independent of other determinants of survival.

"GLI1 Subcellular Localization and Overexpression as Prognostic Factors for Disease-Free Survival in Colorectal Carcinoma"

PURPOSE

Glioma-associated oncogene homolog-1 (GLI1) is amplified in human glioblastoma, and there is growing evidence suggesting its significant role in tumor development and metastasis. Our aim was to investigate the role of the GLI-1 gene in the progression of colorectal cancer (CRC) and its correlation with various clinicopathological features. Additionally, we examined the impact of the GLI-1 gene and other factors on the prognosis of CRC.

METHODS

We analyzed a total of 98 confirmed CRC cases and adjacent normal tissue controls. Patients suspected of having colon cancer underwent a colonoscopy and targeted biopsy, while those with rectal cancer underwent CT scans and MRI. GLI1 expression was detected using real-time PCR assay, Western blotting, and immunohistochemistry.

RESULTS

The GLI1 gene was observed to be overexpressed in tumor tissues at both the protein and mRNA levels (p < 0.05). In addition, GLI1 overexpression was significantly associated with various factors such as tumor invasion (T3/T4), presence of lymph nodes, lymph node metastasis (LNM), stage (III/IV), tumor site (colon), tumor size (≥ 3 cm), localization (nucleocytoplasmic), strong staining intensity and recurrence (p < 0.05). The results of survival analysis showed that the patients with overexpression of GLI1 had a significantly lower DFS rate which was 21 months compared to those with normal expression who had 31 months (p < 0.05). Moreover, individuals with early onset disease (15 months) were more likely to have cytoplasmic localization of the GLI1 gene as opposed to nucleo-cytoplasmic localization of GLI1 which presented late-onset disease( 23 months) (p < 0.05). Finally, Stage and PNI (p < 0.05) were found to independently affect outcomes of CRC according to Cox regression analysis.

CONCLUSION

High expression of GLI-1 in CRC is associated with adverse pathology and poor prognosis for patients. The correlation between cytoplasmic localization of GLI-1 and reduced disease-free survival holds potential for guiding prognosis and treatment. Further research is needed to develop strategies targeting GLI-1 for improved outcomes.

Photobleaching-mediated charge-convertible cyclodextrin nanoparticles achieve deep tumour penetration for rectal cancer theranostics

Although charge-converting nanoparticles (NPs) potentially penetrate tumours deeply, conventional charge conversion strategies possess limitations, including low selectivity and slow, inconsistent conversion rate within the tumour microenvironment. In this study, we synthesized a zwitterionic near-infrared cyclodextrin derivative of heptamethine cyanine and complexed it with pheophorbide-conjugated ferrocene to produce multifunctional theranostic nanotherapeutics. Our NPs demonstrated enhanced tumour-targeting ability, enabling the highly specific imaging of rectal tumours, with tumour-to-rectum signal ratios reaching up to 7.8. The zwitterionic surface charge of the NPs was rapidly converted to a cationic charge within the tumours on 880 nm near-infrared laser irradiation, promoting the tumoural penetration of NPs via transcytosis. After penetration, photodynamic/chemodynamic therapy was initiated using a 660 nm laser. Our NPs eradicated clinically relevant-sized heterotopic tumours (~250 mm3) and orthotopic rectal tumours, displaying their potential as theranostic nanoplatforms for targeting rectal cancer.

Comparative analysis of adhesion virulence protein FadA from gut-associated bacteria of colorectal cancer patients (F. nucleatum) and healthy individuals (E. cloacae)

Background: Colorectal cancer (CRC) is a gastrointestinal disease linked with GIT microbial dysbiosis. The present study has targeted the comparative analysis of virulent factor FadA from gut-associated bacteria of CRC patients (F. nucleatum) and healthy individuals (E. cloacae). Methods: For this purpose, FadA protein sequences of fifteen strains of F. nucleatum and four strains of E. cloacae, were retrieved from the UniProt database. These sequences were analysed through VirulentPred, PSLpred, ProtParam, PFP-FunDSeqE, PROTEUS Structure Prediction Server, SWISS-MODEL, SAVES validation server, MEME suite 5.5.0, CAVER Web tool, Webserver VaxinPAD, HPEPDOCK and HDOCK servers. Results: FadA protein from F. nucleatum was found to exhibit significant differences as compared to E. nucleatum i.e. it exhibited helical configuration, cytoplasmic, periplasmic, outer-membrane and extracellular localisation, 2D structure comprising of 70-96% helix, 0% beta-sheet, 4-30% coils and 17-20 signal peptide residues, hydrophilicity, strongly acidic character and smaller number of antigenic epitopes. In contrast, FadA protein from E. nucleatum was found to have globular 3D configuration, cytoplasmic localisation, 2D structure (30-56% helix, 12-21% beta-sheet, 33-50% coils and 43 signal peptide residues), highly hydrophobic, slightly acidic and more number of antigenic epitopes. Docking analyses of virulent factors revealed their high binding affinities with previously reported inhibitory peptide and FAD-approved drug COX2. Conclusion: The wide range of differences not only provided us the reason for the role of FadA protein as a virulent factor in F. nucleatum but also might help us in designing virulent FadA protein inhibiting strategies including peptide-based vaccine adjuvants and drugs designing, modification of tunnels and catalytic pockets to reduce substrate binding and FAD approved drugs selection. Inhibition of this virulent factor in CRC patients' gut bacteria might result in oncogenesis regression and reduced death rate.

Significance of Gene Polymorphism and Gene Expression of BACE2 in Swedish Patients with Colorectal Cancer

INTRODUCTION

β-site amyloid precursor protein (APP) cleaving enzyme 2 (BACE2) cleaves APP which is ubiquitously expressed in a variety of cell types including cancer cells. BACE2 can process APP in several ways and appears to be involved in the pathogenesis of cancer. Our purpose was to assess the association of mRNA expression and genetic polymorphism of BACE2 in colorectal cancer (CRC) susceptibility and its association to clinicopathological factors in Swedish patients with CRC.

METHODS

A total of 720 CRC patients and 470 healthy controls were genotyped for BACE2 gene polymorphism rs2012050, using TaqMan single nucleotide polymorphism (SNP) assays based on polymerase chain reaction. Reverse transcription quantitative PCR was used to investigate the BACE2 gene expression in 192 CRC tissue and 181 paired normal tissue.

RESULTS

Assessing clinicopathological factors, we noted that carrying of T allele in C/T and C/T+T/T was significantly associated with a protective role against disseminated cancer and higher lymph node status. Moreover, individuals carrying T/T genotype were significantly more likely to have poorly differentiated cancer. Follow-up data for patients in poorly differentiated cancer and the Kaplan-Meier analysis showed that the cancer-specific survival curves differed between C/C and C/T+T/T for the BACE2 gene polymorphism and that the carriers of the genotype C/C were associated with more favorable prognosis. We found no significant differences in the genotypic frequencies between the patients and healthy controls. BACE2 mRNA level was significantly 2.2-fold upregulated in CRC tissue when compared to noncancerous tissue. A higher BACE2 mRNA level was observed in smaller tumors and in rectal cancer when compared to colon cancer.

CONCLUSION

In patients with CRC, our results indicate BACE2 rs2012050 as a useful potential predictor of poor differentiation, disseminated cancer and lymph node status and that the BACE2 mRNA expression is associated to tumor size and cancer location.

Vasorin (VASN) overexpression promotes pulmonary metastasis and resistance to adjuvant chemotherapy in patients with locally advanced rectal cancer

BACKGROUND

LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection.

METHODS

Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome.

RESULTS

Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer.

CONCLUSIONS

Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.

Emergence of rare and low abundant anaerobic gut Firmicutes is associated with a significant downfall of Klebsiella in human colon cancer

Gut bacterial dysbiosis has been linked to several gastrointestinal diseases, including deadly colorectal cancer (CRC), a leading cause of mortality in cancer patients. However, perturbation in gut bacteriome during colon cancer (CC, devoid of colorectal malignancy) remains poorly explored. Here, 16S rRNA gene amplicon sequencing was carried out for fecal DNA samples targeted to hypervariable V3-V4 region by employing MiSeq platform to explore the gut bacterial community shift in CC patients. While alpha diversity indices predicted high species richness and diversity, beta diversity showed marked gut bacterial compositional dissimilarity in CC versus healthy controls (HC, n = 10 each). We observed a significant (p < 0.05, Wilcoxon Rank-Sum test) emergence of low-abundant anaerobic taxa, including Parvimonas and Peptostreptococcus, in addition to Subdoligranulum, Coprococcus, Holdemanella, Solobacterium, Bilophila, Blautia, Dorea, Moryella and several unidentified taxa, mainly affiliated to Firmicutes, in CC patients. In addition, we also traced the emergence of putative probiotic taxon Slackia, belonging to Actinomycetota, in CC patients. The emergence of anaerobic Firmicutes in CC is accompanied by a significant (p < 0.05) decline in the Klebsiella, as determined through linear discriminant analysis effect size (LEfSe) and heat tree analyses. Shifts in core microbiome and variation in network correlation were also witnessed. Taken together, this study highlighted a significant and consistent emergence of rare anaerobic Firmicutes suggesting possible anaerobiosis driving gut microbial community shift, which could be exploited in designing diagnostic and therapeutic tools targeted to CC.

Exploring the physiological role of the G protein-coupled estrogen receptor (GPER) and its associations with human diseases

Estrogen is a group of hormones that collaborate with the nervous system to impact the overall well-being of all genders. It influences many processes, including those occurring in the central nervous system, affecting learning and memory, and playing roles in neurodegenerative diseases and mental disorders. The hormone's action is mediated by specific receptors. Significant roles of classical estrogen receptors, ERα and ERβ, in various diseases were known since many years, but after identifying a structurally and locationally distinct receptor, the G protein-coupled estrogen receptor (GPER), its role in human physiology and pathophysiology was investigated. This review compiles GPER-related information, highlighting its impact on homeostasis and diseases, while putting special attention on functions and dysfunctions of this receptor in neurobiology and biobehavioral processes. Understanding the receptor modulation possibilities is essential for therapy, as disruptions in receptors can lead to diseases or disorders, irrespective of correct estrogen levels. We conclude that studies on the GPER receptor have the potential to develop therapies that regulate estrogen and positively impact human health.

A cuproptosis-related lncRNAs signature predicts prognosis and reveals pivotal interactions between immune cells in colon cancer

Copper-mediated cell death presents distinct pathways from established apoptosis processes, suggesting alternative therapeutic approaches for colon cancer. Our research aims to develop a predictive framework utilizing long-noncoding RNAs (lncRNAs) related to cuproptosis to predict colon cancer outcomes while examining immune interactions and intercellular signaling. We obtained colon cancer-related human mRNA expression profiles and clinical information from the Cancer Genome Atlas repository. To isolate lncRNAs involved in cuproptosis, we applied Cox proportional hazards modeling alongside the least absolute shrinkage and selection operator technique. We elucidated the underlying mechanisms by examining the tumor mutational burden, the extent of immune cell penetration, and intercellular communication dynamics. Based on the model, drugs were predicted and validated with cytological experiments. A 13 lncRNA-cuproptosis-associated risk model was constructed. Two colon cancer cell lines were used to validate the predicted representative mRNAs with high correlation coefficients with copper-induced cell death. Survival enhancement in the low-risk cohort was evidenced by the trends in Kaplan-Meier survival estimates. Analysis of immune cell infiltration suggested that survival was induced by the increased infiltration of naïve CD4+ T cells and a reduction of M2 macrophages within the low-risk faction. Decreased infiltration of naïve B cells, resting NK cells, and M0 macrophages was significantly associated with better overall survival. Combined single-cell analysis suggested that CCL5-ACKR1, CCL2-ACKR1, and CCL5-CCR1 pathways play key roles in mediating intercellular dialogues among immune constituents within the neoplastic microhabitat. We identified three drugs with a high sensitivity in the high-risk group. In summary, this discovery establishes the possibility of using 13 cuproptosis-associated lncRNAs as a risk model to assess the prognosis, unravel the immune mechanisms and cell communication, and improve treatment options, which may provide a new idea for treating colon cancer.

Unveiling Colorectal Cancer Biomarkers: Harnessing Biosensor Technology for Volatile Organic Compound Detection

Conventional screening options for colorectal cancer (CRC) detection are mainly direct visualization and invasive methods including colonoscopy and flexible sigmoidoscopy, which must be performed in a clinical setting and may be linked to adverse effects for some patients. Non-invasive CRC diagnostic tests such as computed tomography colonography and stool tests are either too costly or less reliable than invasive ones. On the other hand, volatile organic compounds (VOCs) are potentially ideal non-invasive biomarkers for CRC detection and monitoring. The present review is a comprehensive presentation of the current state-of-the-art VOC-based CRC diagnostics, with a specific focus on recent advancements in biosensor design and application. Among them, breath-based chromatography pattern analysis and sampling techniques are overviewed, along with nanoparticle-based optical and electrochemical biosensor approaches. Limitations of the currently available technologies are also discussed with an outlook for improvement in combination with big data analytics and advanced instrumentation, as well as expanding the scope and specificity of CRC-related volatile biomarkers.

Association of Clinicopathological Factors With MMP13 (rs2252070) Gene Polymorphism in Swedish Patients With Colorectal Cancer

BACKGROUND/AIM

Matrix metalloproteinase 13 (MMP13) has been reported to be involved in tumor development and progression, including of colorectal cancer (CRC). This study aimed at evaluating whether the MMP13 rs2252070 gene polymorphism is associated with clinicopathological factors and its influence on long-term survival in Swedish patients with CRC.

PATIENTS AND METHODS

A total of 723 patients with CRC were genotyped using TaqMan single nucleotide polymorphism assays based on polymerase chain reaction.

RESULTS

Assessing clinicopathological factors, we demonstrated that having the G/G genotype for MMP13 rs2252070 was significantly associated with poor differentiation, higher serum level of carcinoembryonic antigen and higher lymph node status. Moreover, the presence of a G allele was significantly related to larger tumor size in rectal cancer but had a significantly protective role against mucinous cancer, perineural invasion and lymphovascular invasion. Kaplan-Meier analysis showed no difference between genotypes regarding cancer-specific survival.

CONCLUSION

Our findings highlight the potential of MMP13 rs2252070 polymorphism as a useful predictor of poor differentiation, serum level of carcinoembryonic antigen, lymph node status, tumor size, mucinous cancer, perineural invasion and lymphovascular invasion in patients with CRC.

NFκB signalling in colorectal cancer: Examining the central dogma of IKKα and IKKβ signalling

The NFκB pathway, known as the central regulator of inflammation, has a well-established role in colorectal cancer (CRC) initiation, progression, and therapy resistance. Due to the pathway's overarching roles in CRC, there have been efforts to characterise NFκB family members and target the pathway for therapeutic intervention. Initial research illustrated that the canonical NFκB pathway, driven by central kinase IKKβ, was a promising target for drug intervention. However, dose limiting toxicities and specificity concerns have resulted in failure of IKKβ inhibitors in clinical trials. The field has turned to look at targeting the less dominant kinase, IKKα, which along with NFκB inducing kinase (NIK), drives the lesser researched non-canonical NFκB pathway. However prognostic studies of the non-canonical pathway have produced conflicting results. There is emerging evidence that IKKα is involved in other signalling pathways, which lie outside of canonical and non-canonical NFκB signalling. Evidence suggests that some of these alternative pathways involve a truncated form of IKKα, and this may drive poor cancer-specific survival in CRC. This review aims to explore the multiple components of NFκB signalling, highlighting that NIK may be the central kinase for non-canonical NFκB signalling, and that IKKα is involved in novel pathways which promote CRC.

Incidence, Characteristics and Survival Rates of Bladder Cancer after Rectosigmoid Cancer Radiation

BACKGROUND

Historical external beam radiation therapy (EBRT) for rectosigmoid cancer (RCa) predisposed patients to an increased risk of secondary bladder cancer (BCa). However, no contemporary radiotherapy studies are available. We addressed this knowledge gap.

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2000-2020), we identified non-metastatic RCa patients who either underwent radiotherapy (EBRT+) or did not (EBRT-). Cumulative incidence plots and multivariable competing risk regression models (CRR) were fitted to address rates of BCa after RCa. In the subgroup of BCa patients, the same methodology addressed BCa-specific mortality (BCSM) according to EBRT exposure status.

RESULTS

Of the 188,658 non-metastatic RCa patients, 54,562 (29%) were EBRT+ vs. 134,096 (73%) who were EBRT-. In the cumulative incidence plots, the ten-year BCa rates were 0.7% in EBRT+ vs. 0.7% in EBRT- patients (p = 0.8). In the CRR, EBRT+ status was unrelated to BCa rates (multivariable HR: 1.1, p = 0.8). In the subgroup of 1416 patients with BCa after RCa, 443 (31%) were EBRT+ vs. 973 (69%) who were EBRT-. In the cumulative incidence plots, the ten-year BCSM rates were 10.6% in EBRT+ vs. 12.1% in EBRT- patients (p = 0.7). In the CRR, EBRT+ status was unrelated to subsequent BCSM rates (multivariable HR: 0.9, p = 0.9).

CONCLUSION

Although historical EBRT for RCa predisposed patients to higher BCa rates, contemporary EBRT for RCa is not associated with increased subsequent BCa risk. Moreover, in patients with BCa after RCa, exposure to EBRT does not affect BCSM.

Current Applications and Future Directions of Circulating Tumor Cells in Colorectal Cancer Recurrence

The ability to predict or detect colorectal cancer (CRC) recurrence early after surgery enables physicians to apply appropriate treatment plans and different follow-up strategies to improve patient survival. Overall, 30-50% of CRC patients experience cancer recurrence after radical surgery, but current surveillance tools have limitations in the precise and early detection of cancer recurrence. Circulating tumor cells (CTCs) are cancer cells that detach from the primary tumor and enter the bloodstream. These can provide real-time information on disease status. CTCs might become novel markers for predicting CRC recurrence and, more importantly, for making decisions about additional adjuvant chemotherapy. In this review, the clinical application of CTCs as a therapeutic marker for stage II CRC is described. It then discusses the utility of CTCs for monitoring cancer recurrence in advanced rectal cancer patients who undergo neoadjuvant chemoradiotherapy. Finally, it discusses the roles of CTC subtypes and CTCs combined with clinicopathological factors in establishing a multimarker model for predicting CRC recurrence.

Influence of the COVID-19 Pandemic on Patients with Rectal Cancer

Objectives: The COVID-19 pandemic and its associated restrictions have resulted in delayed diagnoses across various tumor entities, including rectal cancer. Our hypothesis was based on the expectation of a reduced number of primary operations due to higher tumor stages compared to the control group. Methods: In a single-center retrospective study conducted from 1 March 2018 to 1 March 2022, we analyzed 120 patients with an initial diagnosis of rectal cancer. Among them, 65 patients were part of the control group (pre-COVID-19), while 55 patients were included in the study group (during the COVID-19 pandemic). We compared tumor stages, treatment methods, and complications, presenting data as absolute numbers or mean values. Results: Fewer primary tumor resections during the COVID-19 pandemic (p = 0.010), as well as a significantly lower overall number of tumor resections (p = 0.025) were seen compared to the control group. Twenty percent of patients in the COVID-19 group received their diagnosis during lockdown periods. These patients presented significantly higher tumor stages (T4b: 27.3% vs. 6.2%, p = 0.025) compared to the control group prior to the pandemic. In addition, more patients with angiolymphatic invasion (ALI) were identified in the COVID-19 group following neoadjuvant treatment compared to the control group (p = 0.027). No differences were noted between the groups regarding complications, stoma placement, or conversion rates. Conclusions: The COVID-19 pandemic, particularly during lockdown, appears to have contributed to delayed diagnoses, resulting in higher tumor stages and a decreased number of surgeries. The quality of rectal cancer treatment can be maintained under pandemic conditions.

Metformin's role in lowering colorectal cancer risk among individuals with diabetes from the Southern Community Cohort Study

BACKGROUND

Metformin, utilized to manage hyperglycemia, has been linked to a reduced risk of colorectal cancer (CRC) among individuals with diabetes. However, evidence is lacking for non-Hispanic Black individuals and those with lower socioeconomic status (SES), who face elevated risk for both diabetes and CRC. In this study, we investigated the association between metformin use and incident CRC risk within the Southern Community Cohort Study (SCCS), a racially- and SES-diverse prospective cohort.

METHODS

Participants reported their diabetes diagnosis and medications, including metformin, upon enrollment (2002-2009) and during follow-up surveys approximately every five years. Incident cases of CRC were identified through state cancer registries and the National Death Index. Proportional hazards models were employed to explore the relationship between metformin use and CRC risk, adjusted for cancer risk factors.

RESULTS

A total of 25,992 participants with diabetes were included in the analysis, among whom 10,095 were taking metformin. Of these participants, 76% identified as non-Hispanic Black, and 60% reported household incomes <$15,000/year. Metformin use was associated with a significantly lower CRC risk (HR [95% CI]: 0.71 [0.55-0.93]), with consistent results for both colon (0.80 [0.59-1.07]) and rectal cancers (0.49 [0.28-0.86]). The protective association appeared to be stronger among non-Hispanic White individuals (0.51 [0.31-0.85]) compared to non-Hispanic Black participants (0.80 [0.59-1.08], p-interaction =.13). Additionally, a protective association was observed among obese individuals (BMI ≥30 kg/m2, 0.59 [0.43-0.82] but not among non-obese participants (0.99 [0.65-1.51], p-interaction =.05) CONCLUSION: Our findings indicate that metformin use is associated with a reduced risk of CRC in individuals with diabetes, including among those from predominantly low SES backgrounds. These results support previous epidemiological findings, and demonstrate that the protective association for metformin in relation to incident CRC likely generalizes to populations with higher underlying risk.

Procyanidin C1 inhibits tumor growth and metastasis in colon cancer via modulating miR-501-3p/HIGD1A axis

INTRODUCTION

Although colon (COAD) and rectal adenocarcinoma (READ) combined to refer to colorectal cancer (CRC), substantial clinical evidence urged that CRC should be treated as two different cancers due to compared with READ, COAD showed higher morbidity and worse 5-year survival.

OBJECTIVES

This study has tried to screen for the crucial gene that caused the worse prognosis and investigate its mechanism for mediating tumor growth and metastases in COAD. Meanwhile, the potential anti-COAD compound implicated in this mechanism was identified and testified from 1,855 food-borne chemical kits. This study aims to bring a new perspective to the development of new anti-COAD drugs and personalized medicine for patients with COAD.

METHODS AND RESULTS

The survival-related hub genes in COAD and READ were screened out from The Cancer Genome Atlas (TCGA) database and the results showed that HIGD1A, lower expressed in COAD than in READ, was associated with poor prognosis in COAD patients, but not in READ. Over-expressed HIGD1A suppressed CRC cell proliferation, invasion, and migration in vitro and in vivo. Meanwhile, the different expressed microRNA profiles between COAD and READ showed that miR-501-3p was highly expressed in COAD and inhibited HIGD1A expression by targeting 3'UTR of HIGD1A. MiR-501-3p mimics promoted cell proliferation and metastasis in CRC cells. In addition, Procyanidin C1 (PCC1), a kind of natural polyphenol has been verified as a potential miR-501-3p inhibitor. In vitro and in vivo, PCC1 promoted HIGD1A expression by suppressing miR-501-3p and resulted in inhibited tumor growth and metastasis.

CONCLUSION

The present study verified that miR-501-3p/HIGD1A axis mediated tumor growth and metastasis in COAD. PCC1, a flavonoid that riched in food exerts anti-COAD effects by inhibiting miR-501-3p and results in the latter losing the ability to suppress HIGD1A expression. Subsequently, unfettered HIGD1A inhibited tumor growth and metastasis in COAD.

Sporadic deficient mismatch repair in colorectal cancer increases the risk for non-colorectal malignancy: A European multicenter cohort study

BACKGROUND AND OBJECTIVES

Disparities between tumors arising via different sporadic carcinogenetic pathways have not been studied systematically. This retrospective multicenter cohort study evaluated the differences in the risk for non-colorectal malignancy between sporadic colorectal cancer (CRC) patients from different DNA mismatch repair status.

METHODS

A retrospective European multicenter cohort study including in total of 1706 CRC patients treated between 1996 and 2019 in three different countries. The proficiency (pMMR) or deficiency (dMMR) of mismatch repair was determined by immunohistochemistry. Cases were analyzed for tumor BRAFV600E mutation, and BRAF mutated tumors were further analyzed for hypermethylation status in the promoter region of MLH1 to distinguish between sporadic and hereditary cases. Swedish and Finish patients were matched with their respective National Cancer Registries. For the Czech cohort, thorough scrutiny of medical files was performed to identify any non-colorectal malignancy within 20 years before or after the diagnosis of CRC. Poisson regression analysis was performed to identify the incidence rates of non-colorectal malignancies. For validation purposes, standardized incidence ratios were calculated for the Swedish cases adjusted for age, year, and sex.

RESULTS

Of the 1706 CRC patients included in the analysis, 819 were female [48%], median age at surgery was 67 years [interquartile range: 60-75], and sporadic dMMR was found in 188 patients (11%). Patients with sporadic dMMR CRC had a higher incidence rate ratio (IRR) for non-colorectal malignancy before and after diagnosis compared to patients with a pMMR tumor, in both uni- (IRR = 2.49, 95% confidence interval [CI] = 1.89-3.31, p = 0.003) and multivariable analysis (IRR = 2.24, 95% CI = 1.67-3.01, p = 0.004). This association applied whether or not the non-colorectal tumor developed before or after the diagnosis of CRC in both uni- (IRR = 1.91, 95% CI = 1.28-2.98, p = 0.004), (IRR = 2.45, 95% CI = 1.72-3.49, p = 0.004) and multivariable analysis (IRR = 1.67,95% CI = 1.05-2.65, p = 0.029), (IRR = 2.35, 95% CI = 1.63-3.42, p = 0.005), respectively.

CONCLUSION

In this retrospective European multicenter cohort study, patients with sporadic dMMR CRC had a higher risk for non-colorectal malignancy than those with pMMR CRC. These findings indicate the need for further studies to establish the need for and design of surveillance strategies for patients with dMMR CRC.

Analysis of the nischarin expression across human tumor types reveals its context-dependent role and a potential as a target for drug repurposing in oncology

Nischarin was reported to be a tumor suppressor that plays a critical role in breast cancer initiation and progression, and a positive prognostic marker in breast, ovarian and lung cancers. Our group has found that nischarin had positive prognostic value in female melanoma patients, but negative in males. This opened up a question whether nischarin has tumor type-specific and sex-dependent roles in cancer progression. In this study, we systematically examined in the public databases the prognostic value of nischarin in solid tumors, regulation of its expression and associated signaling pathways. We also tested the effects of a nischarin agonist rilmenidine on cancer cell viability in vitro. Nischarin expression was decreased in tumors compared to the respective healthy tissues, most commonly due to the deletions of the nischarin gene and promoter methylation. Unlike in healthy tissues where it was located in the cytoplasm and at the membrane, in tumor tissues nischarin could also be observed in the nuclei, implying that nuclear translocation may also account for its cancer-specific role. Surprisingly, in several cancer types high nischarin expression was a negative prognostic marker. Gene set enrichment analysis showed that in tumors in which high nischarin expression was a negative prognostic marker, signaling pathways that regulate stemness were enriched. In concordance with the findings that nischarin expression was negatively associated with pathways that control cancer growth and progression, nischarin agonist rilmenidine decreased the viability of cancer cells in vitro. Taken together, our study lays a ground for functional studies of nischarin in a context-dependent manner and, given that nischarin has several clinically approved agonists, provides rationale for their repurposing, at least in tumors in which nischarin is predicted to be a positive prognostic marker.

Meta-analysis: loop ileostomy versus colostomy to prevent complications of anterior resection for rectal cancer

PURPOSE

Anastomotic leakage is a serious complication of colorectal cancer surgery, prolonging hospital stays and impacting patient prognosis. Preventive colostomy is required in patients at risk of anastomotic fistulas. However, it remains unclear whether the commonly used loop colostomy(LC) or loop ileostomy(LI) can reduce the complications of colorectal surgery. This study aims to compare perioperative morbidities associated with LC and LI following anterior rectal cancer resection, including LC and LI reversal.

METHODS

In this meta-analysis, the Embase, Web of Science, Scopus, PubMed, and Cochrane Library databases were searched for prospective cohort studies, retrospective cohort studies, and randomized controlled trials (RCTs) on perioperative morbidity during stoma development and reversal up to July 2023, The meta-analysis included 10 trials with 2036 individuals (2 RCTs and 8 cohorts).

RESULTS

No significant differences in morbidity, mortality, or stoma-related issues were found between the LI and LC groups after anterior resection surgery. However, patients in the LC group exhibited higher rates of stoma prolapse (RR: 0.39; 95%CI: 0.19-0.82; P = 0.01), retraction (RR: 0.45; 95%CI: 0.29-0.71; P < 0.01), surgical site infection (RR: 0.52; 95%CI: 0.27-1.00; P = 0.05) and incisional hernias (RR: 0.53; 95%CI: 0.32-0.89; P = 0.02) after stoma closure compared to those in the LI group. Conversely, the LI group showed higher rates of dehydration or electrolyte imbalances(RR: 2.98; 95%CI: 1.51-5.89; P < 0.01), high-output(RR: 6.17; 95%CI: 1.24-30.64; P = 0.03), and renal insufficiency post-surgery(RR: 2.51; 95%CI: 1.01-6.27; P = 0.05).

CONCLUSION

Our study strongly recommends a preventive LI for anterior resection due to rectal cancer. However, ileostomy is more likely to result in dehydration, renal insufficiency, and intestinal obstruction. More multicenter RCTs are needed to corroborate this.

Identification of unique rectal cancer-specific subtypes

BACKGROUND

Existing colorectal cancer subtyping methods were generated without much consideration of potential differences in expression profiles between colon and rectal tissues. Moreover, locally advanced rectal cancers at resection often have received neoadjuvant chemoradiotherapy which likely has a significant impact on gene expression.

METHODS

We collected mRNA expression profiles for rectal and colon cancer samples (n = 2121). We observed that (i) Consensus Molecular Subtyping (CMS) had a different prognosis in treatment-naïve rectal vs. colon cancers, and (ii) that neoadjuvant chemoradiotherapy exposure produced a strong shift in CMS subtypes in rectal cancers. We therefore clustered 182 untreated rectal cancers to find rectal cancer-specific subtypes (RSSs).

RESULTS

We identified three robust subtypes. We observed that RSS1 had better, and RSS2 had worse disease-free survival. RSS1 showed high expression of MYC target genes and low activity of angiogenesis genes. RSS2 exhibited low regulatory T cell abundance, strong EMT and angiogenesis signalling, and high activation of TGF-β, NF-κB, and TNF-α signalling. RSS3 was characterised by the deactivation of EGFR, MAPK and WNT pathways.

CONCLUSIONS

We conclude that RSS subtyping allows for more accurate prognosis predictions in rectal cancers than CMS subtyping and provides new insight into targetable disease pathways within these subtypes.

External validation of the colorectal cancer risk score LiFeCRC using food frequency questions in the HUNT study

PURPOSE

To mitigate the increasing colorectal cancer (CRC) incidence globally and prevent CRC at the individual level, individual lifestyle information needs to be easily translated into CRC risk assessment. Several CRC risk prediction models exist and their clinical usefulness depends on their ease of use. Our objectives were to assess and externally validate the LiFeCRC score in our independent, unselected population and to investigate the use of simpler food frequency measurements in the score.

METHODS

Incidental colon and rectal cancer cases were compared to the general population among 78,580 individuals participating in a longitudinal health study in Norway (HUNT). Vegetable, dairy product, processed meat and sugar/confectionary consumption was scored based on food frequency. The LiFeCRC risk score was calculated for each individual.

RESULTS

Over a median of 10 years following participation in HUNT, colon cancer was diagnosed in 1355 patients and rectal cancer was diagnosed in 473 patients. The LiFeCRC score using food frequencies demonstrated good discrimination in CRC overall (AUC 0.77) and in sex-specific models (AUC men 0.76 and women 0.77) in this population also including individuals ≥ 70 years and patients with diabetes. It performed somewhat better in colon (AUC 0.80) than in rectal cancer (AUC 0.72) and worked best for female colon cancer (AUC 0.81).

CONCLUSION

Readily available clinical variables and food frequency questions in a modified LiFeCRC score can identify patients at risk of CRC and may improve primary prevention by motivating to lifestyle change or participation in the CRC screening programme.

Influence of skeletal muscle and intermuscular fat on postoperative complications and long-term survival in rectal cancer patients

BACKGROUND

The body composition of patients with rectal cancer potentially affects postoperative outcomes. This study explored the correlations between skeletal muscle and adipose tissue quantified by computed tomography (CT) with postoperative complications and long-term prognosis in patients with rectal cancer after surgical resection.

METHODS

This retrospective cohort study included patients with rectal cancer who underwent surgical resection at the Wuhan Union Hospital between 2014 and 2018. CT images within 3 months prior to the surgery were used to quantify the indices of skeletal muscle and adipose tissue at the levels of the third lumbar vertebra (L3) and umbilicus. Optimal cut-off values for each index were defined separately for males and females. Associations between body composition and postoperative complications, overall survival (OS), and disease-free survival (DFS) were evaluated using logistic and Cox proportional hazards models.

RESULTS

We included 415 patients (240 males and 175 females; mean age: 57.8 ± 10.5 years). At the L3 level, a high skeletal muscle density (SMD; hazard ratio [HR]: 0.357, 95% confidence interval [CI]: 0.191-0.665, P = 0.001; HR: 0.571, 95% CI: 0.329-0.993, P = 0.047) and a high skeletal muscle index (SMI; HR: 0.435, 95% CI 0.254-0.747, P = 0.003; HR: 0.568, 95% CI: 0.359-0.897, P = 0.015) were independent prognostic factors for better OS and DFS. At the umbilical level, a large intermuscular fat area (IMFA; HR: 1.904, 95% CI: 1.068-3.395, P = 0.029; HR: 2.064, 95% CI: 1.299-3.280, P = 0.002) was an independent predictive factor for worse OS and DFS, and a high SMI (HR: 0.261, 95% CI: 0.132-0.517, P < 0.001; HR: 0.595, 95% CI: 0.387-0.913, P = 0.018) was an independent prognostic factor for better OS and DFS. The models combining body composition and clinical indicators had good predictive abilities for OS. The receiver operating characteristic areas under the curve were 0.848 and 0.860 at the L3 and umbilical levels, respectively (both P < 0.05).

CONCLUSIONS

No correlations existed between CT-quantified body composition parameters and postoperative complications. However, a high SMD and high SMI were significantly associated with longer OS and DFS at the L3 level, whereas a large IMFA and low SMI were associated with worse OS and DFS at the umbilical level. Combining CT-quantified body composition and clinical indicators could help physicians predict the prognosis of patients with rectal cancer after surgery.

Diverging likelihood of colon and rectal cancer in Yogyakarta, Indonesia: A cross sectional study

OBJECTIVES

Colon and rectal cancer are associated with different risk factors and prognostic. However, this discrepancy has not been widely explored in the local population. This study aimed to investigate the site-specific likelihood of colorectal cancer (CRC) incidence in the Yogyakarta province, Indonesia.

METHODS

This cross-sectional study analyses 1,295 CRC cases diagnosed in 2008-2019 registered in the Yogyakarta population-based cancer registry (PBCR) database. Cases were grouped into colon and rectal cancer. Log-binomial regression was used to determine the relative risk of either colon or rectal cancer across different gender, age group, and rurality of residence. The age-specific rates were calculated by age group and temporal trend for each group were analyzed using joinpoint regression.

RESULTS

Females displayed higher odds of colon cancer (relative risk/RR = 1.20, 95%CI = 1.02-1.41) and lower odds of rectal cancer (RR = 0.92, 95%CI = 0.85-0.99). Elevated odds of colon cancer were observed in younger age group, especially 30-39 (RR = 1.87, 95%CI = 1.10-3.19), while decreased odds of rectal cancer was apparent in age group 30-39 and 40-49 (RR = 0.75, 95%CI = 0.60-0.93 and RR = 0.82, 95%CI = 0.69-0.98, respectively). Living in urban or rural areas did not significantly influence the odds of either having colon (RR = 0.98, 95%CI = 0.82-1.17) or rectal cancer (RR = 1.01, 95%CI = 0.93-1.10). During 2008-2019, trends of colon cancer in age <50 increased by 8.15% annually while rectal cancer displayed a 9.71% increase annually prior to 2017, followed by a 17.23% decrease until 2019.

CONCLUSIONS

Yogyakarta population shows higher odds of young-onset colon cancer, especially between age 30-39 years old. Overall observation of trend shows increasing incidence in young-onset colon cancer, and non-significant decrease in rectal cancer.

Preoperative assessment of grade, T stage, and lymph node involvement: machine learning-based CT texture analysis in colon cancer

PURPOSE

To investigate whether texture analysis of primary colonic mass in preoperative abdominal computed tomography (CT) scans of patients diagnosed with colon cancer could predict tumor grade, T stage, and lymph node involvement using machine learning (ML) algorithms.

MATERIALS AND METHODS

This retrospective study included 73 patients diagnosed with colon cancer. Texture features were extracted from contrast-enhanced CT images using LifeX software. First, feature reduction was performed by two radiologists through reproducibility analysis. Using the analysis of variance method, the parameters that best predicted lymph node involvement, grade, and T stage were determined. The predictive performance of these parameters was assessed using Orange software with the k-nearest neighbor (kNN), random forest, gradient boosting, and neural network models, and their area under the curve values were calculated.

RESULTS

There was excellent reproducibility between the two radiologists in terms of 49 of the 58 texture parameters that were subsequently subject to further analysis. Considering all four ML algorithms, the mean AUC and accuracy ranges were 0.557-0.800 and 47-76%, respectively, for the prediction of lymph node involvement; 0.666-0.846 and 68-77%, respectively, for the prediction of grade; and 0.768-0.962 and 81-88%, respectively, for the prediction of T stage. The best performance was achieved with the random forest model in the prediction of LN involvement, the kNN model for the prediction of grade, and the gradient boosting model for the prediction of T stage.

CONCLUSION

The results of this study suggest that the texture analysis of preoperative CT scans obtained for staging purposes in colon cancer can predict the presence of advanced-stage tumors, high tumor grade, and lymph node involvement with moderate specificity and sensitivity rates when evaluated using ML models.

Interplay of miRNAs and lncRNAs in STAT3 signaling pathway in colorectal cancer progression

In recent decades, colorectal cancer (CRC) has turned into one of the most widespread malignancies, and the incidence of this malignancy is expected to increase. Despite considerable improvements in therapeutic approaches, the prognosis, and the management of CRC face many problems. Likely, the main limitation in the successful treatment of CRC is the lack of appropriate clinical therapeutic targets. As an effective target, the signal transducer and activator of transcription 3 (STAT3) are regulated by a wide range of genes and involved in cellular processes, including cell growth, migration, invasion, immunosuppression, and angiogenesis. Aberrant regulation of STAT3 signaling leads to cellular dysfunction, diseases, and malignancies, including CRC. Consequently, targeting this signaling pathway is considered one of the therapeutic strategies used in CRC treatment. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are non-coding RNA molecules with partial or no protein-coding activity that participate in gene regulation at epigenetic, transcriptional, and post-transcriptional levels and regulate multiple signaling pathways, including STAT3 signaling (especially JAK/STAT). Therefore, these regulatory molecules are suggested to be very promising targets to present new insights into overcoming the limitations of conventional therapeutic strategies. Therefore, the current review study aimed to summarize the therapeutic and diagnostic significance of miRNAs and lncRNAs and their therapeutic and diagnostic significance related to the expression and activity of STAT3 in CRC.

Comprehensive characterization of PKHD1 mutation in human colon cancer

INTRODUCTION

The PKHD1 (Polycystic Kidney and Hepatic Disease 1) gene is essential for producing fibrocystin or polyductin, which is crucial in various cellular functions. Mutations in PKHD1 have been found to be involved in the development and progression of colorectal cancer (CRC). Along with APC, TP53, and KRAS, PKHD1 is one of the most frequently mutated genes in CRC. PKHD1 expression is governed by the Wnt/PCP pathway, often dysregulated in CRC. Targeting this pathway, crucial for CRC progression, could unveil potential therapeutic strategies for colon cancer treatment.

METHODS

This study examined an in-house dataset of 3702 colon cancer samples, analyzing mutation landscapes, clinical features, tumor mutational burden (TMB), microsatellite instability (MSI), and chromosomal instability (CIN) score. For the survival analysis of PKHD1 patients, survival data of 436 colon adenocarcinoma samples were obtained from TCGA dataset. Additionally, 433 samples from TCGA with RNA-seq data were used for the assessment of immune cell infiltration and gene set enrichment analysis.

RESULTS

Polycystic Kidney and Hepatic Disease 1 mutation was detected in 424 colon cancer patients from our in-house cohort and was associated with increased TMB, higher MSI, and lower CIN score. Importantly, within the TCGA dataset, PKHD1 mutations were identified as an independent prognostic factor, not merely correlated with established prognostic biomarkers, and were associated with poorer overall survival outcomes. In terms of immune response, these mutations correlated with increased enrichment scores for 12 immune cell types, including B cell plasma, macrophages, and naive CD4+ T cells. Additionally, interferon alpha and interferon-gamma gene sets were significantly down-regulated in patients with PKHD1 mutations (FDA q-value < 0.1).

CONCLUSIONS

Overall, these findings suggest that PKHD1 may be a potential biomarker for the prognosis of colon cancer and provide some insight for personalized immunotherapy.

Advancing Colorectal Cancer Diagnosis with AI-Powered Breathomics: Navigating Challenges and Future Directions

Early detection of colorectal cancer is crucial for improving outcomes and reducing mortality. While there is strong evidence of effectiveness, currently adopted screening methods present several shortcomings which negatively impact the detection of early stage carcinogenesis, including low uptake due to patient discomfort. As a result, developing novel, non-invasive alternatives is an important research priority. Recent advancements in the field of breathomics, the study of breath composition and analysis, have paved the way for new avenues for non-invasive cancer detection and effective monitoring. Harnessing the utility of Volatile Organic Compounds in exhaled breath, breathomics has the potential to disrupt colorectal cancer screening practices. Our goal is to outline key research efforts in this area focusing on machine learning methods used for the analysis of breathomics data, highlight challenges involved in artificial intelligence application in this context, and suggest possible future directions which are currently considered within the framework of the European project ONCOSCREEN.

A Review of Scheduling Strategies for Radiotherapy and Immune Checkpoint Inhibition in Locally Advanced Rectal Cancer

Colorectal cancer (CRC) is the third most common malignancy across the globe and, despite advances in treatment strategies, survival rates remain low. Rectal cancer (RC) accounts for most of these cases, and traditional management strategies for advanced disease include total neoadjuvant therapy (TNT) with chemoradiotherapy followed by curative surgery. Unfortunately, approximately 10-15% of patients have no response to treatment or have recurrence at a short interval following radiotherapy. The introduction of immunotherapy in the form of immune checkpoint blockade (ICB) in metastatic colorectal cancer has improved clinical outcomes, yet most patients with RC present with microsatellite stable disease, which lacks the immune-rich microenvironment where ICB is most effective. There is evidence that combining radiotherapy with ICB can unlock the mechanisms that drive resistance in patients; however, the sequencing of these therapies is still debated. This review offers a comprehensive overview of clinical trials and preclinical models that use radiotherapy-immunotherapy combinations in RC in an attempt to extrapolate the ideal sequencing of the two treatment modalities. The results highlight the dearth of evidence to answer the question of whether ICB should be given before, during, or after radiotherapy, yet it is suggested that improving the relevance of our preclinical models will provide a platform with higher translational value and will lead to appropriate clinical trial designs.

A Retrospective Comparison of Toxicity, Response and Survival of Intensity-Modulated Radiotherapy Versus Three-Dimensional Conformal Radiation Therapy in the Treatment of Rectal Carcinoma

INTRODUCTION

The main target of neoadjuvant treatment in rectal cancer is to downstage and downsize large tumours to increase the chance of complete surgical resection, and therefore decrease the chances of local recurrence. With or without the addition of chemotherapy, until recently, three-dimensional conformal radiotherapy (3D-CRT) used to be the radiotherapy treatment modality of choice. However, intensity-modulated radiotherapy (IMRT) is being increasingly adopted by many radiotherapy centres as a more modern, conformal technique due to its ability to minimize radiation dose to nearby organs. The aim of our analysis was to assess the difference in toxicity, response to treatment, and survival between the patients treated with these two different treatment modalities in our institution.

METHODS

We performed a retrospective analysis of data and compared two groups of patients with locally advanced rectal cancer who were treated with either 3D-CRT or IMRT. The main outcomes were radiation toxicity and response to treatment. Overall survival was a secondary outcome.

RESULTS

One hundred and thirty-six patients were included in the study: 71 patients treated with 3D-CRT and 65 patients treated with IMRT. With regard to toxicity, there was no significant difference between the groups for bladder and skin toxicity, but there was a significant reduction in acute grade 2 bowel toxicity in patients treated with a long course of IMRT [3D-CRT 77% (48/62) vs IMRT 64% (30/47) p=0.042]. There was no statistically significant difference in the treatment response rates of these two radiotherapy treatment modalities, as well as in overall survival between the groups (p=0.604).  Conclusion: Our study showed that IMRT can significantly reduce acute bowel side effects for patients undergoing neoadjuvant radiotherapy for locally advanced rectal cancers. Further studies are needed to confirm the clinical advantage of IMRT in rectal carcinoma.

Implications of Rectal Cancer Radiotherapy on the Immune Microenvironment: Allies and Foes to Therapy Resistance and Patients' Outcome

Aside from surgical resection, locally advanced rectal cancer is regularly treated with neoadjuvant chemoradiotherapy. Since the concept of cancer treatment has shifted from only focusing on tumor cells as drivers of disease progression towards a broader understanding including the dynamic tumor microenvironment (TME), the impact of radiotherapy on the TME and specifically the tumor immune microenvironment (TIME) is increasingly recognized. Both promoting as well as suppressing effects on anti-tumor immunity have been reported in response to rectal cancer (chemo-)radiotherapy and various targets for combination therapies are under investigation. A literature review was conducted searching the PubMed database for evidence regarding the pleiotropic effects of (chemo-)radiotherapy on the rectal cancer TIME, including alterations in cytokine levels, immune cell populations and activity as well as changes in immune checkpoint proteins. Radiotherapy can induce immune-stimulating and -suppressive alterations, potentially mediating radioresistance. The response is influenced by treatment modalities, including the dosage administered and the highly individual intrinsic pre-treatment immune status. Directly addressing the main immune cells of the TME, this review aims to highlight therapeutical implications since efficient rectal cancer treatment relies on personalized strategies combining conventional therapies with immune-modulating approaches, such as immune checkpoint inhibitors.

Advances in rectal cancer: Real-world evidence suggests limited gains in prognosis for elderly patients

BACKGROUND

Rectal cancer treatment has improved considerably due to the introduction of total meso-rectal excision, radio-chemotherapy, and high-resolution imaging. The aim of this observational cohort study was to quantify the effectiveness of these advances using high-quality data from a representative cohort of patients.

METHODS

20 281 non-metastasized cases retrieved from the Munich Cancer Registry database were divided into three time periods corresponding to before (1988-1997), partial (1998-2007), and full implementation (2008-2019) of clinical advances. Early-onset (<50 yrs.), middle-aged, elderly patient subgroups (> 70 yrs.) were compared. The overall effectiveness of evidence-based guideline adherence was also examined.

RESULTS

Median survival improved by 1.5 yrs. from the first to the last time period. Relative survival increased from 74.9% (5-yr 95%CI[73.3 - 76.6]) to 79.2% (95%CI[77.8 - 80.5]). The incidence of locoregional recurrences was reduced dramatically by more than half (5-yr 17.7% (95%CI[16.5 - 18.8]); 6.7% (95%CI[6.1 - 7.3])). Gains in 5-yr relative survival were limited to early-onset and middle-aged patients with no significant improvement seen in elderly patients (Female 68.6% [63.9 - 73.3] to 67.6% [64.0 - 71.2]; Male 71.7% [65.9 - 77.4] to 74.0% [70.8 - 77.2]).

CONCLUSIONS

Real-world evidence suggests that recent treatment advances have lead to an increase in prognosis for rectal cancer patients. However, more effort should be made to improve the implementation of new developments in elderly patients. Especially considering, that these cases represent a growing majority of diagnosed patients.

Racial and ethnic differences in colon cancer surgery type performed and delayed treatment among people 45 years old and older in the USA between 2007 and 2017: Mediating effect on survival

BACKGROUND

This study examined the associations of socioeconomic status (SES), race/ethnicity, surgery type, and treatment delays with mortality among colon cancer patients. In addition, the study also quantifies the extent to which clinical and SES factors' variations explain the racial/ethnic differences in overall survival.

PATIENTS AND METHODS

We studied 111,789 adult patients ≥45 years old who were diagnosed with colon cancer between 2010 and 2017, identified from the Surveillance, Epidemiology, and End Results (SEER) database. We performed logistic regression models to examine the association of SES and race/ethnicity with surgery type and first course of treatment delays. We also performed mediation analysis to quantify the extent to which treatment, sociodemographic and clinicopathologic factors mediated racial/ethnic differences in survival.

RESULTS

Non-Hispanic (NH) Blacks [adjusted Odds Ratio (aOR) = 1.19, 95% CI:1.13-1.25] were significantly more likely to undergo subtotal colectomy and to experience treatment delays [aOR = 1.39, 95% CI: 1.31-1.48] compared to NH Whites. Hispanics [aOR = 1.59, 95% CI: 1.49-1.69] were more likely to experience treatment delays than NH Whites. Delayed first course of treatment explained 23.56% and 56.73% of the lower survival among NH Blacks and Hispanics, respectively, compared to their NH White counterparts.

CONCLUSIONS

Race/ethnicity is significantly associated with the surgery type performed and the first course of treatment delays. Variations in treatment, SES, and clinicopathological factors significantly explained racial disparities in overall mortality. These disparities highlight the need for multidisciplinary interventions to address the treatment and social factors perpetuating racial disparities in colon cancer mortality.

Biological functions and molecular subtypes regulated by miR-142-3p in colon cancer

MicroRNA-142-3p (miR-142-3p) has been reported to be implicated in colon cancer; however, the possible regulatory mechanisms and molecular subtypes regulated by miR-142-3p have not been fully elucidated. This study aimed to investigate the biological functions and regulatory mechanism of miR-142-3p in colon cancer. The expression level of miR-142-3p in colon cancer was analyzed based on the mRNA and miRNA expression datasets of colon cancer retrieved from The Cancer Genome Atlas. Target genes of miR-142-3p were also predicted. Based on these target genes, the functions and subtypes of miR-142-3p were investigated. The metabolic and tumor-related pathways, immune microenvironment, and target gene expression between the 2 subtypes were analyzed. MiR-142-3p was upregulated in tumor tissues, and its high expression indicated a poor prognosis. A total of 39 target genes were predicted, which were significantly involved in autophagy- and metabolism-related functions and pathways. Based on these target genes, the colon cancer samples were clustered into 2 subtypes. There were 35 metabolism-related pathways that were significantly different between the 2 clusters. The immune and stromal scores in cluster 2 were higher than those in cluster 1, whereas the tumor purity of cluster 2 was significantly lower than that of cluster 1. TP53INP2 expression in cluster 2 was higher than that in cluster 1. MiR-142-3p may promote colon cancer progression via autophagy- and metabolism-related pathways. MiR-142-3p may be served as a candidate target for the treatment of colon cancer.

Immunohistochemical Expression of Glutathione Peroxidase-2 (Gpx-2) and Its Clinical Relevance in Colon Adenocarcinoma Patients

Glutathione peroxidase 2 (Gpx-2) is a selenoenzyme with antioxidant capabilities that may play a role in cancer development. Hence, we investigated the immunohistochemical expression of Gpx-2 protein in colon adenocarcinoma samples derived from patients with colon adenocarcinoma who did not receive any form of treatment prior to the surgical procedure. The associations between the immunohistochemical expression of Gpx-2 and clinical parameters were analysed using the Chi2 test and Fisher's exact test. A Kaplan-Meier analysis and the log-rank test were used to verify the relationship between the intensity of Gpx-2 expression and the 5-year survival rate of patients. In total, 101 (80.80%) samples had strong Gpx-2 protein expression and 24 (19.20%) samples were characterized with low expression. The high expression of Gpx-2 was correlated with the histological grade of the tumour (p < 0.001), PCNA immunohistochemical expression (p < 0.001), depth of invasion (p = 0.001) and angioinvasion (p < 0.001). We can conclude that high expression of Gpx-2 is correlated with reduced survival of colon adenocarcinoma patients (log-rank, p < 0.001).

The psoas muscle density as a predictor of postoperative complications in elderly patients undergoing rectal cancer resection

Background

Muscle depletion that impairs normal physiological function in elderly patients leads to poor prognosis. This study aimed to evaluate the association between total abdominal muscle area (TAMA), total psoas area (TPA), psoas muscle density (PMD), and short-term postoperative complications in elderly patients with rectal cancer.

Methods

All elderly patients underwent rectal cancer resection with perioperative abdominal computed tomography (CT). Complications were assessed according to the Clavien-Dindo classification. Severe complications were defined as grade III-V following the Clavien-Dindo classification. Univariate and multivariate analyses were performed to evaluate risk factors of short-term severe postoperative complications.

Results

The cohort consisted of 191 patients with a mean age of 73.60 ± 8.81 years. Among them, 138 (72.25%) patients had Clavien-Dindo 0- II, 53 (27.75%) patients had severe postoperative complications (Clavien-Dindo III-V), and 1(0.52%) patient died within 30 days of surgery. PMD was significantly higher in the Clavien-Dindo 0-II cohort compared to the Clavien-Dindo III-V cohort (p=0.004). Nevertheless, TAMA and TPA failed to exhibit significant differences. Moreover, the multivariate regression analysis implied that advanced age [OR 1.07 95%CI (1.02-1.13) p=0.013], male [OR 5.03 95%CI (1.76-14.41) p=0.003], high charlson comorbidity index (CCI) score [OR 3.60 95%CI (1.44-9.00) p=0.006], and low PMD [OR 0.94 95%CI (0.88-0.99) p=0.04] were independent risk factors of Clavien-Dindo III-V.

Conclusion

Preoperative assessment of the PMD on CT can be a simple and practical method for identifying elderly patients with rectal cancer at risk for severe postoperative complications.

The optimal surgery timing after stenting in colorectal cancer patients with malignant obstruction: additionally compared with emergency surgery

BACKGROUND

This study aimed to determine short-term and long-term outcomes according to time intervals after stenting and compared them with those of emergency surgery (ES) in colorectal cancer (CRC) with malignant obstruction.

METHODS

CRC with malignant obstructions was reviewed retrospectively between January 2008 and July 2018. Of a total of 539 patients who visited the emergency room and underwent ES, 133 were enrolled in the ES group. Of a total of 567 patients who initially received stenting and subsequently underwent elective surgery, 220 were enrolled in the SEMS group. The interval between SEMS placement and elective surgery was classified as < 11 days, 11-17 days, and > 17 days.

RESULTS

For those who received SEMS (n = 220), those with a time interval of 11-17 days (n = 97) had fewer hospital days than those with a time interval of < 11 days (n = 68) (8 days vs. 15 days) and less stoma formation than those with a time interval of > 17 days (n = 55) (1.0% vs. 14.6%). Multivariable analysis revealed a decreased risk of death for the group with a time interval of 11-17 days (20.6%) compared to the ES group (31.6%) (hazard ratio: 0.48; 95% confidence interval: 0.24-0.97). Disease-free survival was comparable between the SEMS and ES groups regardless of the time interval (log-rank p = 0.52).

CONCLUSIONS

The time interval of 11-17 days after stenting to elective surgery appeared to be associated with the most favorable outcomes.

Radiomic Features Are Predictive of Response in Rectal Cancer Undergoing Therapy

BACKGROUND

Rectal cancer is a major mortality cause in the United States (US), and its treatment is based on individual risk factors for recurrence in each patient. In patients with rectal cancer, accurate assessment of response to chemoradiotherapy has increased in importance as the variety of treatment options has grown. In this scenario, a controversial non-operative approach may be considered in some patients for whom complete tumor regression is believed to have occurred. The recommended treatment for locally advanced rectal cancer (LARC, T3-4 ± N+) is total mesorectal excision (TME) after neoadjuvant chemoradiotherapy (nCRT). Magnetic resonance imaging (MRI) has become a standard technique for local staging of rectal cancer (tumor, lymph node, and circumferential resection margin [CRM] staging), in both the US and Europe, and it is getting widely used for restaging purposes.

AIM

In our study, we aimed to use an MRI radiomic model to identify features linked to the different responses of chemoradiotherapy of rectal cancer before surgery, and whether these features are helpful to understand the effectiveness of the treatments.

METHODS

We retrospectively evaluated adult patients diagnosed with LARC who were subjected to at least 2 MRI examinations in 10-12 weeks at our hospital, before and after nCRT. The MRI acquisition protocol for the 2 exams included T2 sequence and apparent diffusion coefficient (ADC) map. The patients were divided into 2 groups according to the treatment response: complete or good responders (Group 1) and incomplete or poor responders (Group 2). MRI images were segmented, and quantitative features were extracted and compared between the two groups. Features that showed significant differences (SF) were then included in a LASSO regression method to build a radiomic-based predictive model.

RESULTS

We included 38 patients (26 males and 12 females), who are classified from T2 and T4 stages in the rectal cancer TNM. After the nCRT, the patients were divided into Group 1 (13 patients), complete or good responders, and Group 2 (25 patients), incomplete or poor responders. Analysis at baseline generated the following significant features for the Mann-Whitney test (out of a total of 107) for each sequence. Also, the analysis at the end of the follow-up yielded a high number of significant features for the Mann-Whitney test (out of a total of 107) for each image. Features selected by the LASSO regression method for each image analyzed; ROC curves relative to each model are represented.

CONCLUSION

We developed an MRI-based radiomic model that is able to differentiate and predict between responders and non-responders who went through nCRT for rectal cancer. This approach might identify early lesions with high surgical potential from lesions potentially resolving after medical treatment.

High OCT4 Expression Might Be Associated with an Aggressive Phenotype in Rectal Cancer

Rectal cancer (RC) is one of the most common malignant neoplasms, and cancer stem cells (CSCs) of the intestinal tract have been implicated in its origin. The oncofetal protein OCT4 has been linked to neoplastic processes, but its role and clinical significance in RC are unknown. This study investigates the expression of the stem cell marker OCT4 related to clinical-pathological characteristics and its clinical significance in RC patients. The expression level of stem cell marker OCT4 was analyzed in 22 primary rectal tumors by western blot. The association between OCT4 protein expression and the clinical-pathological features of tumors was evaluated by χ² test and Fisher's exact test. We demonstrated that the expression of the stem cell marker OCT4 was observed in tumor tissue but not adjacent non-tumor tissue. High expression of the stem cell marker OCT4 was significantly associated with histological differentiation grade (p = 0.039), tumor invasion level (p = 0.004), lymph node involvement (p = 0.044), tumor-node-metastasis (TNM) stage (p = 0.002), and clinical stage (p = 0.021). These findings suggest that high OCT4 expression is associated with a more aggressive RC phenotype, with a greater likelihood of progression and metastasis. These results shed light on the importance of targeting this CSC marker to attenuate RC progression.

Cancer Wars: Revenge of the AMPs (Antimicrobial Peptides), a New Strategy against Colorectal Cancer

Cancer is a multifaceted health issue that affects people globally and it is considered one of the leading causes of death with a high percentage of victims worldwide. In recent years, research studies have uncovered great advances in cancer diagnosis and treatment. But, there are still major drawbacks of the conventional therapies used including severe side effects, toxicity, and drug resistance. That is why it is critical to develop new drugs with advantages like low cytotoxicity and no treatment resistance to the cancer cells. Antimicrobial peptides (AMPs) have recently attracted attention as a novel therapeutic strategy for the treatment of various cancers, targeting tumor cells with less toxicity to normal tissues. The aim of the study was to discover alternate treatments that do not lead to cancer resistance and have fewer side effects. Here, we report the effects induced by several AMPs, Melittin, Cecropin A, and a Cecropin A-Melittin hybrid, against two human colorectal cancer-derived spheroids. To study the effects of the peptides, cell viability was investigated using MTT, LDH, and ATP assays. Furthermore, cellular senescence and cell cycle were investigated. We found that using different concentrations of these peptides affected the spheroids, their structure being highly compromised by reducing cell viability, and the increase in ATP and LDH levels. Also, the cells are arrested in the G2/M phase leading to an increase in senescent cells. We show that Melittin and the hybrid are most effective against the 3D colorectal cancer cells compared to Cecropin A.

Higher Plasma Creatinine Is Associated with an Increased Risk of Death in Patients with Non-Metastatic Rectal but Not Colon Cancer: Results from an International Cohort Consortium

Colorectal cancer (CRC) is increasingly recognized as a heterogeneous disease. No studies have prospectively examined associations of blood metabolite concentrations with all-cause mortality in patients with colon and rectal cancer separately. Targeted metabolomics (Biocrates AbsoluteIDQ p180) and pathway analyses (MetaboAnalyst 4.0) were performed on pre-surgery collected plasma from 674 patients with non-metastasized (stage I-III) colon (n = 394) or rectal cancer (n = 283). Metabolomics data and covariate information were received from the international cohort consortium MetaboCCC. Cox proportional hazards models were computed to investigate associations of 148 metabolite levels with all-cause mortality adjusted for age, sex, tumor stage, tumor site (whenever applicable), and cohort; the false discovery rate (FDR) was used to account for multiple testing. A total of 93 patients (14%) were deceased after an average follow-up time of 4.4 years (60 patients with colon cancer and 33 patients with rectal cancer). After FDR adjustment, higher plasma creatinine was associated with a 39% increase in all-cause mortality in patients with rectal cancer. HR: 1.39, 95% CI 1.23-1.72, pFDR = 0.03; but not colon cancer: pFDR = 0.96. Creatinine is a breakdown product of creatine phosphate in muscle and may reflect changes in skeletal muscle mass. The starch and sucrose metabolisms were associated with increased all-cause mortality in colon cancer but not in rectal cancer. Genes in the starch and sucrose metabolism pathways were previously linked to worse clinical outcomes in CRC. In summary, our findings support the hypothesis that colon and rectal cancer have different etiological and clinical outcomes that need to be considered for targeted treatments.

Data mining identifies novel RNA-binding proteins involved in colon and rectal carcinomas

Colorectal adenocarcinoma (COREAD) is the second most deadly cancer and third most frequently encountered malignancy worldwide. Despite efforts in molecular subtyping and subsequent personalized COREAD treatments, multidisciplinary evidence suggests separating COREAD into colon cancer (COAD) and rectal cancer (READ). This new perspective could improve diagnosis and treatment of both carcinomas. RNA-binding proteins (RBPs), as critical regulators of every hallmark of cancer, could fulfill the need to identify sensitive biomarkers for COAD and READ separately. To detect new RBPs involved in COAD and READ progression, here we used a multidata integration strategy to prioritize tumorigenic RBPs. We analyzed and integrated 1) RBPs genomic and transcriptomic alterations from 488 COAD and 155 READ patients, 2) ∼ 10,000 raw associations between RBPs and cancer genes, 3) ∼ 15,000 immunostainings, and 4) loss-of-function screens performed in 102 COREAD cell lines. Thus, we unraveled new putative roles of NOP56, RBM12, NAT10, FKBP1A, EMG1, and CSE1L in COAD and READ progression. Interestingly, FKBP1A and EMG1 have never been related with any of these carcinomas but presented tumorigenic features in other cancer types. Subsequent survival analyses highlighted the clinical relevance of FKBP1A, NOP56, and NAT10 mRNA expression to predict poor prognosis in COREAD and COAD patients. Further research should be performed to validate their clinical potential and to elucidate their molecular mechanisms underlying these malignancies.

Colorectal Cancer in the Young: Research in Early Age Colorectal Cancer Trends (REACCT) Collaborative

Background: The incidence of colorectal cancer (CRC) is increasing in the young (under 50). Defining the clinicopathological features and cancer-specific outcomes of patients with early-onset CRC is important to optimize screening and treatment strategies. This study evaluated disease-specific features and oncological outcomes of patients with early-onset CRC. Methods: Anonymized data from an international collaboration were analyzed. The inclusion criteria for this study were patients aged <50 years with stage I-III disease surgically resected with curative intent. Overall and disease-free survival were calculated using the Kaplan-Meier method. Results: A total of 3378 patients were included, with a median age of 43 (18-49) and a slight male preponderance (54.3%). One-third had a family history of colorectal cancer. Almost all (>95%) of patients were symptomatic at diagnosis. The majority (70.1%) of tumors were distal to the descending colon. Approximately 40% were node positive. Microsatellite instability was demonstrated in one in five patients, representing 10% of rectal and 27% of colon cancers. A defined inherited syndrome was diagnosed in one-third of those with microsatellite instability. Rectal cancer displayed a worse prognosis stage for stage. Five-year disease-free survival for stage I, II, and III colon cancer was 96%, 91%, and 68%, respectively. The equivalent rates for rectal cancer were 91%, 81%, and 62%. Conclusions and relevance: The majority of EOCRC would be captured with flexible sigmoidoscopy. Extending screening to young adults and public health education initiatives are potential interventions to improve survivorship.

Immune Response and Immune Checkpoint Molecules in Patients with Rectal Cancer Undergoing Neoadjuvant Chemoradiotherapy: A Review

It is well-established that tumor antigens and molecules expressed and secreted by cancer cells trigger innate and adaptive immune responses. These two types of anti-tumor immunity lead to the infiltration of the tumor's microenvironment by immune cells with either regulatory or cytotoxic properties. Whether this response is associated with tumor eradication after radiotherapy and chemotherapy or regrowth has been a matter of extensive research through the years, mainly focusing on tumor-infiltrating lymphocytes and monocytes and their subtypes, and the expression of immune checkpoint and other immune-related molecules by both immune and cancer cells in the tumor microenvironment. A literature search has been conducted on studies dealing with the immune response in patients with rectal cancer treated with neoadjuvant radiotherapy or chemoradiotherapy, assessing its impact on locoregional control and survival and underlying the potential role of immunotherapy in the treatment of this cancer subtype. Here, we provide an overview of the interactions between local/systemic anti-tumor immunity, cancer-related immune checkpoint, and other immunological pathways and radiotherapy, and how these affect the prognosis of rectal cancer patients. Chemoradiotherapy induces critical immunological changes in the tumor microenvironment and cancer cells that can be exploited for therapeutic interventions in rectal cancer.