Global colorectal cancer burden in 2020 and projections to 2040

MTU: A multi-tasking U-net with hybrid convolutional learning and attention modules for cancer classification and gland Segmentation in Colon Histopathological Images

A clinically comparable multi-tasking computerized deep U-Net-based model is demonstrated in this paper. It intends to offer clinical gland morphometric information and cancer grade classification to be provided as referential opinions for pathologists in order to abate human errors. It embraces enhanced feature learning capability that aids in extraction of potent multi-scale features; efficacious semantic gap recovery during feature concatenation; and successful interception of resolution-degradation and vanishing gradient problems while performing moderate computations. It is proposed by integrating three unique novel structural components namely Hybrid Convolutional Learning Units in the encoder and decoder, Attention Learning Units in skip connection, and Multi-Scalar Dilated Transitional Unit as the transitional layer in the traditional U-Net architecture. These units are composed of the amalgamated phenomenon of multi-level convolutional learning through conventional, atrous, residual, depth-wise, and point-wise convolutions which are further incorporated with target-specific attention learning and enlarged effectual receptive field size. Also, pre-processing techniques of patch-sampling, augmentation (color and morphological), stain-normalization, etc. are employed to burgeon its generalizability. To build network invariance towards digital variability, exhaustive experiments are conducted using three public datasets (Colorectal Adenocarcinoma Gland (CRAG), Gland Segmentation (GlaS) challenge, and Lung Colon-25000 (LC-25K) dataset)) and then its robustness is verified using an in-house private dataset of Hospital Colon (HosC). For the cancer classification, the proposed model achieved results of Accuracy (CRAG(95%), GlaS(97.5%), LC-25K(99.97%), HosC(99.45%)), Precision (CRAG(0.9678), GlaS(0.9768), LC-25K(1), HosC(1)), F1-score (CRAG(0.968), GlaS(0.977), LC 25K(0.9997), HosC(0.9965)), and Recall (CRAG(0.9677), GlaS(0.9767), LC-25K(0.9994), HosC(0.9931)). For the gland detection and segmentation, the proposed model achieved competitive results of F1-score (CRAG(0.924), GlaS(Test A(0.949), Test B(0.918)), LC-25K(0.916), HosC(0.959)); Object-Dice Index (CRAG(0.959), GlaS(Test A(0.956), Test B(0.909)), LC-25K(0.929), HosC(0.922)), and Object-Hausdorff Distance (CRAG(90.47), GlaS(Test A(23.17), Test B(71.53)), LC-25K(96.28), HosC(85.45)). In addition, the activation mappings for testing the interpretability of the classification decision-making process are reported by utilizing techniques of Local Interpretable Model-Agnostic Explanations, Occlusion Sensitivity, and Gradient-Weighted Class Activation Mappings. This is done to provide further evidence about the model's self-learning capability of the comparable patterns considered relevant by pathologists without any pre-requisite for annotations. These activation mapping visualization outcomes are evaluated by proficient pathologists, and they delivered these images with a class-path validation score of (CRAG(9.31), GlaS(9.25), LC-25K(9.05), and HosC(9.85)). Furthermore, the seg-path validation score of (GlaS (Test A(9.40), Test B(9.25)), CRAG(9.27), LC-25K(9.01), HosC(9.19)) given by multiple pathologists is included for the final segmented outcomes to substantiate the clinical relevance and suitability for facilitation at the clinical level. The proposed model will aid pathologists to formulate an accurate diagnosis by providing a referential opinion during the morphology assessment of histopathology images. It will reduce unintentional human error in cancer diagnosis and consequently will enhance patient survival rate.

High prevalence of Cryptosporidium infection in Iranian patients suffering from colorectal cancer

The present investigation was designed to study the prevalence of cryptosporidiosis in the colorectal cancer patients compared to the healthy subjects. The present descriptive case-control study was performed on 174 subjects including 87 healthy people and 87 patients with colorectal cancer attending to general hospitals in Lorestan Province, Western Iran, during October 2019–August 2020. A fresh stool specimen was collected from each subject in a sterile labeled container. The collected stool samples were concentrated using the sucrose flotation method and then prepared for Ziehl-Neelsen staining for microscopic examination. All samples were also tested using the Nested-PCR assays by amplifying the 18S rRNA gene for the presence of Cryptosporidium DNA. Demographic and possible risk factors such as age, gender, residence, agriculture activity, history of contact with livestock, consumption unwashed fruits/vegetables, and hand washing before eating were investigated in all the studied subjects using a questionnaire. Of the 87 patients with colorectal cancer, 37 (42.5%) had Cryptosporidium infection. A significant difference (p < 0.001) in the prevalence of Cryptosporidium spp. infections among the participants in the case and control (11, 12.6%) groups was observed. We found that cryptosporidiosis was not linked with age, gender, hand washing, agriculture activity, and history of contact with livestock in the colorectal patients. However, residence in urban areas was significantly associated with the prevalence of cryptosporidiosis. The 18 s rRNA gene of Cryptosporidium in 48 samples was successfully amplified by the Nested-PCR. Based on the obtained findings, Cryptosporidium spp. infections were observed significantly more frequently in the patients with colorectal cancer in comparison with the healthy individuals. It is suggested to carry out similar studies in various parts of Iran with larger sample sizes and further parasitological tests.

Genome-wide screening for differentially methylated long noncoding RNAs identifies LIFR-AS1 as an epigenetically regulated lncRNA that inhibits the progression of colorectal cancer

Background

Aberrant DNA methylation is an epigenetic marker that has been linked to the pathogenesis of colorectal cancer (CRC). Long noncoding RNAs (lncRNAs) have been increasingly identified to be associated with tumorigenic processes of CRC. Identifying epigenetically dysregulated lncRNAs and characterizing their effects during carcinogenesis are focuses of cancer research.

Methods

Differentially methylated loci and expressed lncRNAs were identified by integrating DNA methylome and transcriptome analyses using The Cancer Genome Atlas database. Bisulfite sequencing PCR (BSP) was performed to analyze LIFR-AS1 promoter methylation status. The functional roles of LIFR-AS1 in CRC were determined by in vitro and in vivo experiments.

Results

We identified a novel hypermethylated lncRNA, LIFR-AS1, that was downregulated and associated with tumorigenesis, metastasis, and poor prognosis in CRC. High methylation burden of LIFR-AS1 indicated a poor survival of CRC patients. Promoter hypermethylation of LIFR-AS1 in tumor tissues was confirmed by BSP. Functional assays revealed that LIFR-AS1 could competitively bind to hsa-miR-29b-3p, and repressed colon cancer cell proliferation, colony formation and invasion. LIFR-AS1 also inhibited tumor growth in a mouse xenograft model of CRC.

Conclusions

Our results showed that the identified DNA methylation-dysregulated lncRNAs may be potential biomarkers and highlighted a role for LIFR-AS1 as a tumor suppressor in CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-022-01361-0.

Hepcidin Upregulation in Colorectal Cancer Associates with Accumulation of Regulatory Macrophages and Epithelial-Mesenchymal Transition and Correlates with Progression of the Disease

Advanced, metastatic colorectal cancer (CRC) is associated with high rate of mortality because of its poor responsiveness to chemotherapy/immunotherapy. Recent studies have shown that hepcidin, a peptide hormone produced mainly by hepatocytes, is expressed by and enhances the growth of tumor cells. We here assessed whether hepcidin expression helps identify subsets of CRC with advanced and aggressive course. By integrating results of in vitro/ex vivo studies with data of bioinformatics databases, we initially showed that hepcidin RNA and protein expression was more pronounced in tissue samples taken from the tumor area, as compared to the macroscopically unaffected, adjacent, colonic mucosa of CRC patients. The induction of hepcidin in the colonic epithelial cell line HCEC-1ct by interleukin (IL)-6, IL-21 and IL-23 occurred via a Stat3-dependent mechanism and, in primary CRC cells, hepcidin co-localized with active Stat3. In CRC tissue, hepcidin content correlated mainly with macrophage accumulation and IL-10 and CD206 expression, two markers of regulatory macrophages. Consistently, both IL-10 and CD206 were up-regulated by hepcidin in blood mononuclear cells. The highest levels of hepcidin were found in metastatic CRC and survival analysis showed that high expression of hepcidin associated with poor prognosis. Moreover, hepcidin expression correlated with markers of epithelial-to-mesenchymal transition and the silencing of hepcidin in CRC cells reduced epithelial-to-mesenchymal transition markers. These findings indicate that hepcidin is markedly induced in the advanced stages of CRC and suggest that it could serve as a prognostic biomarker in CRC.

Injectable Carbon Dots-Based Hydrogel for Combined Photothermal Therapy and Photodynamic Therapy of Cancer

Hydrogel has been widely used in modern biotherapeutics due to its excellent biocompatibility, degradability, and high drug loading capacity. Among them, the construction of a phototherapy system including photosensitizer and hydrogel has aroused great interest in tumor therapy. Unfortunately, complex modifications are necessary to integrate different photosensitizers into the hydrogel. In this work, an injectable hydrogel was proposed by the Schiff base reaction between HA-CHO and carbon dots (CDs), which can realize PTT and PTT simultaneously. Notably, the CDs with rich -NH2 can be used not only as a photosensitizer but also as an efficient cross-linking agent for the Schiff base reaction to form a hydrogel network. The CD@Hydrogel with outstanding biosafety showed a high antitumor effect after 660 nm laser irradiation in in vitro and in vivo experiments. In summary, the CD@Hydrogel can not only realize PTT and PDT synergistic treatment under one light source but also act as a cross-linking agent to react with HA-CHO to form hydrogel, which is simple and efficient, providing a new strategy for cancer phototherapy.

Role of AMPK in Regulation of Oxaliplatin-Resistant Human Colorectal Cancer

Oxaliplatin is a platinum analog that can interfere with DNA replication and transcription. Continuous exposure to oxaliplatin results in chemoresistance; however, this mechanism is not well known. In this study, oxaliplatin-resistant (OR) colorectal cancer (CRC) cells of HCT116, HT29, SW480 and SW620 were established by gradually increasing the drug concentration to 2.5 μM. The inhibitory concentrations of cell growth by 50% (IC50) of oxaliplatin were 4.40-12.7-fold significantly higher in OR CRC cells as compared to their respective parental (PT) CRC cells. Phospho-Akt and phospho-mammalian target of rapamycin (mTOR) decreased in PT CRC cells but was overexpressed in OR CRC cells in response to oxaliplatin. In addition, an oxaliplatin-mediated decrease in phospho-AMP-activated protein kinase (AMPK) in PT CRC cells induced autophagy. Contrastingly, an increased phospho-AMPK in OR CRC cells was accompanied by a decrease in LC3B, further inducing the activity of glycolytic enzymes, such as glucose transporter 1 (GLUT1), 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) and phosphofructokinase 1 (PFK1), to mediate cell survival. Inhibition of AMPK in OR CRC cells induced autophagy through inactivation of Akt/mTOR pathway and a decrease in GLUT1, PFKFB3, and PFK1. Collectively, targeting AMPK may provide solutions to overcome chemoresistance in OR CRC cells and restore chemosensitivity to anticancer drugs.

Advancing immune checkpoint blockade in colorectal cancer therapy with nanotechnology

Immune checkpoint blockade (ICB) has gained unparalleled success in the treatment of colorectal cancer (CRC). However, undesired side effects, unsatisfactory response rates, tumor metastasis, and drug resistance still hinder the further application of ICB therapy against CRC. Advancing ICB with nanotechnology can be game-changing. With the development of immuno-oncology and nanomaterials, various nanoplatforms have been fabricated to enhance the efficacy of ICB in CRC treatment. Herein, this review systematically summarizes these recent nano-strategies according to their mechanisms. Despite their diverse and complex designs, these nanoplatforms have four main mechanisms in enhancing ICB: 1) targeting immune checkpoint inhibitors (ICIs) to tumor foci, 2) increasing tumor immunogenicity, 3) remodeling tumor microenvironment, and 4) pre-sensitizing immune systems. Importantly, advantages of nanotechnology in CRC, such as innovating the mode-of-actions of ICB, modulating intestinal microbiome, and integrating the whole process of antigen presentation, are highlighted in this review. In general, this review describes the latest applications of nanotechnology for CRC immunotherapy, and may shed light on the future design of ICB platforms.

Applications of Nano/Micromotors for Treatment and Diagnosis in Biological Lumens

Natural biological lumens in the human body, such as blood vessels and the gastrointestinal tract, are important to the delivery of materials. Depending on the anatomic features of these biological lumens, the invention of nano/micromotors could automatically locomote targeted sites for disease treatment and diagnosis. These nano/micromotors are designed to utilize chemical, physical, or even hybrid power in self-propulsion or propulsion by external forces. In this review, the research progress of nano/micromotors is summarized with regard to treatment and diagnosis in different biological lumens. Challenges to the development of nano/micromotors more suitable for specific biological lumens are discussed, and the overlooked biological lumens are indicated for further studies.

Phosphorylated Proteins from Serum: A Promising Potential Diagnostic Biomarker of Cancer

Cancer is a fatal disease worldwide. Each year ten million people are diagnosed around the world, and more than half of patients eventually die from it in many countries. A majority of cancer remains asymptomatic in the earlier stages, with specific symptoms appearing in the advanced stages when the chances of adequate treatment are low. Cancer screening is generally executed by different imaging techniques like ultrasonography (USG), mammography, CT-scan, and magnetic resonance imaging (MRI). Imaging techniques, however, fail to distinguish between cancerous and non-cancerous cells for early diagnosis. To confirm the imaging result, solid and liquid biopsies are done which have certain limitations such as invasive (in case of solid biopsy) or missed early diagnosis due to extremely low concentrations of circulating tumor DNA (in case of liquid biopsy). Therefore, it is essential to detect certain biomarkers by a noninvasive approach. One approach is a proteomic or glycoproteomic study which mostly identifies proteins and glycoproteins present in tissues and serum. Some of these studies are approved by the Food and Drug Administration (FDA). Another non-expensive and comparatively easier method to detect glycoprotein biomarkers is by ELISA, which uses lectins of diverse specificities. Several of the FDA approved proteins used as cancer biomarkers do not show optimal sensitivities for precise diagnosis of the diseases. In this regard, expression of phosphoproteins is associated with a more specific stage of a particular disease with high sensitivity and specificity. In this review, we discuss the expression of different serum phosphoproteins in various cancers. These phosphoproteins are detected either by phosphoprotein enrichment by immunoprecipitation using phosphospecific antibody and metal oxide affinity chromatography followed by LC-MS/MS or by 2D gel electrophoresis followed by MALDI-ToF/MS analysis. The updated knowledge on phosphorylated proteins in clinical samples from various cancer patients would help to develop these serum phophoproteins as potential diagnostic/prognostic biomarkers of cancer.

Colorectal Cancer Screening Program Results in Iran

Background: Colorectal cancer (CRC) accounts for a large proportion of the global burden of cancer and is the fourth leading cause of cancer-related mortality worldwide. Fecal Immunochemical Testing (FIT) can be used for CRC screening programs due to its high accuracy and compliance. The present study reports the preliminary results of the CRC screening program in Iran among all people aged 50 to 69 years. Methods: This cross-sectional study was carried out on 2,669,625 participants referred to health centers in Iran for CRC screening programs in 2018 and 2019. The data required for this study was taken from the CRC screening program. Relevant information for all individuals aged 50 to 69 referred to the health system that was called for colorectal cancer screening was extracted from the Integrated Electronic Health Records (SIB) database. Finally, the standards indices were calculated for all provinces. Gender, history of inflammatory bowel disease (IBD) (Crohn's disease or ulcerative colitis), history of colon cancer or adenoma in a first-degree family (father, mother, siblings or children), history of colon cancer in a second-degree family if occurred under the age of fifty (aunt, uncle, grandparents), lower gastrointestinal bleeding in a prior month, constipation in the prior month (with or without diarrhea, abdominal pain and feeling of fullness in the colon after defecation), more than ten percent weight loss in the last six months and FIT were assessed. Results: Among a total number of over 2.6 million, 56.3% were female, and the number of people evaluated by health care providers for CRC screening programs in 2018 and 2019 were 1,365,248 (14.23%) and 1,304,377 (12.89%), respectively. The number of people with positive FIT evaluated for the CRC screening program in 2018 and 2019 was 33,299 (3.09%) and 33,583 (2.57%), respectively. Bushehr province (0.59%) and Isfahan province (7.35%) had the lowest and highest positive FIT rate in 2018, respectively. Also, the correlation between the above-mentioned variables and the number of people with a positive FIT across gender was statistically significant (p<0.05). The study of the relationship between the number of positive FIT cases and the variables examined by Behvarz and community health worker showed that the number of people with a family history of colon cancer in second-degree relatives under the age of 50 and also the number of people with an individual history of inflammatory bowel disease had a significant association with the number of positive FIT cases (p<0.05) (β=-0.718, 95% CI; -2.557-14.992, β=0.388, 95% CI; 0.322-16.737, respectively). The relationship between the number of positive FIT cases and effective variables was not statistically significant (p>0.05). Conclusion: Positive cases should be referred for further evaluation and colonoscopy. Before performing a screening program, the conditions for performing colonoscopy for these people must be assessed and prepared. The FIT for CRC screening program can be easily promoted in Iran.

Advanced stage presentation and its determinant factors among colorectal cancer patients in Amhara regional state Referral Hospitals, Northwest Ethiopia

INTRODUCTION

Nowadays, the burden of colorectal cancer (CRC) has been increasing in the world, particularly in developing nations. This could be related to the poor prognosis of the disease due to late presentation at diagnosis and poor treatment outcomes. In Ethiopia, studies related to the stage of colorectal cancer at diagnosis and its determinants are limited. Therefore, the study was intended to assess advanced stage presentation and its associated factors among colorectal cancer patients in northwest Ethiopia.

METHODS

An institution-based retrospective study was conducted among 367 CRC patients at two oncologic centers (the University of Gondar and Felege Hiwot comprehensive specialized hospitals) from January 1, 2017, to December 31, 2020. Data were entered into EPi-data 4.2.0.0 and transferred to STATA version 14 statistical software for analysis. Binary logistic regression was used to identify factors associated with the outcome variable. All variables with P-value < 0.2 during bi-variable analysis were considered for multivariable logistic regression. The level of statistical significance was declared at P-value <0.05.

RESULTS

The magnitude of advanced stage presentation of colorectal cancer was 83.1%. Being rural dwellers (Adjusted odds ratio (AOR) = 3.6; 95% CI: 1.8,7.2), not medically insured (AOR = 3.9; 95% CI: 1.9,7.8), patients delay (AOR = 6.5; 95% CI:3.2, 13.3), recurrence of the disease (AOR = 2.3; 95% CI: 1.1,4.7), and no comorbidity illness (AOR = 4.4; 95% CI: 2.1, 9.1) were predictors of advanced stage presentation of CRC.

CONCLUSION

The current study revealed that the advanced-stage presentation of colorectal cancer patients was high. It is recommended that the community shall be aware of the signs and symptoms of the disease using different media, giving more emphasis to the rural community, expanding health insurance, and educating patients about the recurrence chance of the disease. Moreover, expansion of colorectal treatment centers and screening of colorectal cancer should be given emphasis.

Disparities in All-Cause Mortality in Older Patients with Colorectal Cancer According to Disability Status: A Nationwide Analysis

BACKGROUND

Although investigating patterns of cancer mortality is important in understanding the effect of cancer on population health, knowledge regarding mortality in cancer patients with disability is scarce. This study examined the association between disability status and all-cause mortality in older patients with colorectal cancer.

METHODS

Data were obtained from the 2008-2019 National Health Insurance Service claims data. The study population included patients with colorectal cancer aged 60 years or above. The outcome measure was all-cause 5-year and overall mortality. A survival analysis was performed using the Cox proportional hazards model to analyze the association between all-cause mortality and disability status. Subgroup analysis was conducted based on disability severity.

RESULTS

The study population consisted of 6340 patients, and disability was reported in 15.8% of the included individuals. Participants with disability had a higher risk of both all-cause 5-year (hazard ratio (HR) 1.21, 95% confidence interval (95% CI) 1.07-1.37) and overall mortality (HR 1.15, 95% CI 1.03-1.28). These findings were particularly significant in individuals with severe rather than mild disability.

CONCLUSION

Older colorectal cancer patients with disabilities showed a higher risk of overall and 5-year all-cause mortality, which was evident in individuals with severe disabilities. The findings indicated disparities in mortality according to disability status. Further, we suggest that policies that can mediate such disparities must be strengthened.

First Report on the Streptococcus gallolyticus (S. bovis Biotype I) DSM 13808 Exopolysaccharide Structure

Streptococcus gallolyticus subspecies gallolyticus, known as Streptococcus bovis biotype I, is a facultative pathogen causing bacteraemia, infective endocarditis and sepsis that has been linked with colorectal cancer (CRC), but this correlation is still unclear. Bacterial surface structures, such as the major sugar antigens exposed to the outside of the microorganism, are potential virulence factors. One of the primary sugar antigens loosely attached to the cell surface is the biofilm component, exopolysaccharide (EPS). EPSs of S. bovis are poorly characterized molecules. Until now, only one S. macedonicus Sc136 EPS structure was known to the entire S. bovis group. The S. gallolyticus DSM 13808 EPS was investigated by chemical analysis, mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The hexasaccharide repeating unit of the EPS, containing four Glc, two Rha residues and one phosphate group, has been described “ →6)-α-d-Glcp-(1→3)-β-l-Rhap-(1→4)-β-d-Glcp-(1→3)-[β-d-Glcp-(1→2)]-α-l-Rhap-(1→2)-α-d-Glcp-(1→P→”.

Biomarkers in Metastatic Colorectal Cancer: Status Quo and Future Perspective

Colorectal cancer (CRC) is the third most frequent cancer worldwide, and its incidence is steadily increasing. During the last two decades, a tremendous improvement in outcome has been achieved, mainly due to the introduction of novel drugs, targeted treatment, immune checkpoint inhibitors (CPIs) and biomarker-driven patient selection. Moreover, progress in molecular diagnostics but also improvement in surgical techniques and local ablative treatments significantly contributed to this success. However, novel therapeutic approaches are needed to further improve outcome in patients diagnosed with metastatic CRC. Besides the established biomarkers for mCRC, such as microsatellite instability (MSI) or mismatch repair deficiency (dMMR), RAS/BRAF, sidedness and HER2 amplification, new biomarkers have to be identified to better select patients who derive the most benefit from a specific treatment. In this review, we provide an overview about therapeutic relevant and established biomarkers but also shed light on potential promising markers that may help us to better tailor therapy to the individual mCRC patient in the near future.

Meta-analysis of fecal viromes demonstrates high diagnostic potential of the gut viral signatures for colorectal cancer and adenoma risk assessment

INTRODUCTION

Viruses have been reported as inducers of tumorigenesis. Little studies have explored the impact of the gut virome on the progression of colorectal cancer. However, there is still a problem with the repeatability of viral signatures across multiple cohorts.

OBJECTIVES

The present study aimed to reveal the repeatable gut vial signatures of colorectal cancer and adenoma patients and decipher the potential of viral markers in disease risk assessment for diagnosis.

METHODS

1,282 available fecal metagenomes from 9 published studies for colorectal cancer and adenoma were collected. A gut viral catalog was constructed via a reference-independent approach. Viral signatures were identified by cross-cohort meta-analysis and used to build predictive models based on machine learning algorithms. New fecal samples were collected to validate the generalization of predictive models.

RESULTS

The gut viral composition of colorectal cancer patients was drastically altered compared with healthy, as evidenced by changes in some Siphoviridae and Myoviridae viruses and enrichment of Microviridae, whereas the virome variation in adenoma patients was relatively low. Cross-cohort meta-analysis identified 405 differential viruses for colorectal cancer, including several phages of Porphyromonas, Fusobacterium, and Hungatella that were enriched in patients and some control-enriched Ruminococcaceae phages. In 9 discovery cohorts, the optimal risk assessment model obtained an average cross-cohort area under the curve of 0.830 for discriminating colorectal cancer patients from controls. This model also showed consistently high accuracy in 2 independent validation cohorts (optimal area under the curve, 0.906). Gut virome analysis of adenoma patients identified 88 differential viruses and achieved an optimal area under the curve of 0.772 for discriminating patients from controls.

CONCLUSION

Our findings demonstrate the gut virome characteristics in colorectal cancer and adenoma and highlight gut virus-bacterial synergy in the progression of colorectal cancer. The gut viral signatures may be new targets for colorectal cancer treatment. In addition, high repeatability and predictive power of the prediction models suggest the potential of gut viral biomarkers in non-invasive diagnostic tests of colorectal cancer and adenoma.

Isolinderalactone sensitizes oxaliplatin-resistance colorectal cancer cells through JNK/p38 MAPK signaling pathways

BACKGROUND

Isolinderalactone (ILL), a sesquiterpene lactone compound, can be extracted from the root of Lindera aggregate. Physiological activities of ILL, including anti-inflammatory and anti-proliferative effects, have been investigated in multiple diseases. Nevertheless, little is known regarding its anti-cancer activities and the mechanism of action of ILL in targeting human CRC cells.

PURPOSE

To determine ILL-mediated anti-proliferative effects on oxaliplatin (Ox)-sensitive and resistant colorectal cancer (CRC) cells and underlying mechanisms involved in its effects focusing on signal transduction.

METHODS

Inhibitory effect of ILL on CRC cells was evaluated by analyzing mitochondrial membrane potential (MMP) dysfunction and multi-caspase activity. Apoptosis-regulating proteins and JNK/p38 signaling molecules were monitored by Western blotting. ROS-dependent physiological modifications by ILL were confirmed by pretreatment with N-acetylcysteine (NAC). Moreover, the involvement of JNK/p38 signaling in ROS-mediated apoptosis was verified by treatment with SP600125 (JNK inhibitor) and SB203580 (p38 inhibitor).

RESULTS

ILL decreased cell viability and colony formation in both CRC Ox-sensitive (HCT116 and HT29) and Ox-resistant (OxR) (HCT116-OxR and HT29-OxR) cells. ILL induced G2/M phase cell cycle arrest, ROS generation, phosphorylated (p)JNK/p38 MAPK activation, mitochondrial membrane potential (MMP) depolarization, and multi-caspase activation, which eventually triggered apoptotic cell death of CRC cells. In addition, combined treatment with ILL and SP600125, SB203580, or pan-caspase inhibitor (Z-VAD-FMK) prevented decreases in cell viability seen after treatment with ILL alone. Pretreatment with NAC attenuated ILL-mediated apoptosis, ROS production, and p-JNK/p38 expression.

CONCLUSION

Taken together, our results suggest that ILL can exert its anticancer effect in CRC Ox-sensitive and OxR cells by inducing ROS-mediated apoptosis through JNK/p38 MAPK signaling pathways. This is the first study demonstrating that ILL has a potential to improve drug efficacy against resistance mechanisms, providing a new insight into therapeutic strategies targeting drug-resistant CRC.

Evaluation of histopathological response to neoadjuvant therapy in rectal cancer using slide-free, stain-free multimodal multiphoton microscopy

Neoadjuvant therapy has become a standard treatment for patients with locally advanced rectal cancer to achieve better prognostic outcomes. The response to treatment has been shown to correlate closely with the prognosis. However, current evaluation systems only provide coarse assessment on limited information, due to the lack of accurate and reproducible approach for quantitation of different types of responses. In this study, a novel stain-free, slide-free multimodal multiphoton microscopy imaging technique was applied to image rectal cancer tissues after neoadjuvant therapies with high resolution and contrast. Qualitative and quantitative evaluation of tumor, stromal, and inflammatory responses were demonstrated which are consistent with current tumor regression grading system using American Joint Committee on Cancer criteria, showing the great potential of such approach to build a more informative grading system for accurate and standardizable assessment of neoadjuvant therapy in rectal cancer.

Oxidative Stress and DNA Damage Markers in Colorectal Cancer

Oxidative stress (OS) and inflammation are known to play an important role in chronic diseases, including cancer, and specifically colorectal cancer (CRC). The main objective of this study was to explore the diagnostic potential of OS markers in patients with CRC, which may translate into an early diagnosis of the disease. To do this, we compared results with those in a group of healthy controls and assessed whether there were significant differences. In addition, we explored possible correlations with the presence of tumors and tumor stage, with anemia and with inflammatory markers used in clinical practice. The study included 80 patients with CRC and 60 healthy controls. The following OS markers were analyzed: catalase (CAT), reduced glutathione (GSH) and oxidized glutathione (GSSG) in serum; and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and F2-isoprotanes in urine (F2-IsoPs). Tumor markers (CEA and CA 19.9), anemia markers (hemoglobin, hematocrit and medium corpuscular volume) and inflammatory markers (leukocytes, neutrophils, N/L index, platelets, fibrinogen, C-reactive protein, CRP and IL-6) were also determined. Comparison of means between patients and controls revealed highly significant differences for all OS markers, with an increase in the prooxidant markers GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and a decrease in the antioxidant markers CAT and GSH. Tumor and inflammatory markers (except CRP) correlated positively with GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and negatively with CAT and GSH. In view of the results obtained, OS markers may constitute a useful tool for the early diagnosis of CRC patients.

Fractal and textural imaging identify new subgroups of patients with colorectal cancer based on biophysical properties of the cancer cells

Colorectal cancer (CRC) can been sub-divided, based on the generation of tertiary lymphoid structures (TLS), into CRC with a Crohn's like lymphoid reaction (CLR) representing de novo formation of TLSs or CRC lacking TLSs that show Diffuse Inflammatory infiltration (DII). The association between TLS, early treatment initiation and longer survival highlights the need for deeper patient stratification that could lead to more targeted therapies. We hypothesized that such stratification might be achieved by using digital image analyses. Here we retrospectively analyzed 35 CRC patient samples classified as CLR or DII by digital analysis, focusing on the parameters Fractal dimension, Lacunarity and the textural features Angular second momentum, Correlation, Inverse difference momentum and Entropy. Significant differences in the grades of these parameters between the two patient groups provided preliminary data that additional biophysical information can divide CRC into at least 3 subgroups which encompass CLR and DII. Additional studies are needed to test if this sub-classification aids in the selection of targeted therapy for patients with CRC.

Geographic Distribution and Time Trends of Colorectal Cancer in Brazil from 2005 to 2018

BACKGROUND

Colorectal cancer (CRC) is the third most common malignancy and the second leading cause of cancer-related death in the world. The aim of this study was to investigate the geographic distribution and time trends of CRC in Brazil.

METHODS

Data were retrospectively retrieved from January 2005 to December 2018 from the Brazilian Public Health System. The incidence and lethality rates of CRC per 100,000 inhabitants in each municipality were estimated from hospitalizations and in-hospital deaths and were classified by age, sex, and demographic features.

RESULTS

During the study period, the mean incidence of CRC estimated from hospitalizations and adjusted to available hospital beds more than tripled from 14.6 to 51.4 per 100,000 inhabitants (352%). Increases in CRC incidence were detected in all age ranges, particularly among people aged 50-69 years (266%). Incidence rates increased in all 5 macroregions, with a clear South to North gradient. The greatest changes in incidence and lethality rates were registered in small-sized municipalities. CRC lethality estimated from in-hospital deaths decreased similarly in both sexes, from 12 to 8% for males and females, from 2005 to 2018. The decline in lethality rates was seen in all age ranges, mainly in people aged 50 to 69 years (- 38%).

CONCLUSIONS

CRC incidence is increasing, predominantly above fifty years of age, and also in areas previously considered as having low incidence, but the increase is not paralleled by lethality rates. This suggests recent improvements in CRC screening programs and treatment, but also supports the spread of environmental risk factors throughout the country.

Classification of colorectal cancer based on gene sequencing data with XGBoost model: An application of public health informatics

Purpose: This study aims to classify open-access colorectal cancer gene data and identify essential genes with the XGBoost method, a machine learning method. Materials and Methods: The open-access colorectal cancer gene dataset was used in the study. The dataset included gene sequencing results of 10 mucosae from healthy controls and the colonic mucosa of 12 patients with colorectal cancer. XGboost, one of the machine learning methods, was used to classify the disease. Accuracy, balanced accuracy, sensitivity, selectivity, positive predictive value, and negative predictive value performance metrics were evaluated for model performance. Results: According to the variable selection method, 17 genes were selected, and modeling was performed with these input variables. Accuracy, balanced accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and F1 score obtained from modeling results were 95.5%, 95.8%, 91.7%, 1%, 1%, and 90.9%, and 95.7%, respectively. According to the variable impotance acquired from the XGboost technique results, the CYR61, NR4A, FOSB, and NR4A2 genes can be employed as biomarkers for colorectal cancer. Conclusion: As a consequence of this research, genes that may be linked to colorectal cancer and genetic biomarkers for the illness were identified. In the future, the detected genes' reliability can be verified, therapeutic procedures can be established based on these genes, and their usefulness in clinical practice may be documented.

Vitamin D and Colorectal Cancer: Current Perspectives and Future Directions

Vitamin D is considered to be the main mediator of the beneficial effects of sun exposure. In humans, highest expression of Vitamin D receptors is found in the intestinal tract. In addition, 1α,25-dihydroxyvitamin D3 (or calcitriol), the most active Vitamin D metabolite, plays important homeostatic roles in the intestine, particularly calcium absorption. Vitamin D deficiency is defined as a serum 25-hydroxyvitamin D [25(OH)D] level of < 20 ng/mL. Previous studies show that higher circulating 25(OH)D levels are associated with reduced risk of colorectal cancer (CRC) and improved survival. Most research to date has been conducted in animals, specifically mice. Although human studies have a limited number of participants, one study recruiting a large cohort of patients with advanced or metastatic CRC revealed that higher plasma 25(OH)D levels are associated with improved overall and progression-free survival. However, the effects of Vitamin D supplementation on incidence and mortality of CRC remain inconclusive. Although Vitamin D may help to prevent cancer, there is a paucity of research demonstrating conclusively that Vitamin D alters prognosis after chemotherapy. Here, we review the mechanisms by which Vitamin D affects CRC, as well as the results of clinical, epidemiological, and human intervention studies. We also discuss current perspectives and future directions regarding Vitamin D and CRC.

Anticancer potential of acetone extracts from selected Potentilla species against human colorectal cancer cells

Cinquefoils have been widely used in local folk medicine in Europe and Asia to manage various gastrointestinal inflammations and/or infections, certain forms of cancer, thyroid gland disorders, and wound healing. In the present paper, acetone extracts from aerial parts of selected Potentilla species, namely P. alba (PAL7), P. argentea (PAR7), P. grandiflora (PGR7), P. norvegica (PN7), P. recta (PRE7), and the closely related Drymocalis rupestris (syn. P. rupestris) (PRU7), were analysed for their cytotoxicity and antiproliferative activities against human colon adenocarcinoma cell line LS180 and human colon epithelial cell line CCD841 CoN. Moreover, quantitative assessments of the total polyphenolic (TPC), total tannin (TTC), total proanthocyanidins (TPrC), total flavonoid (TFC), and total phenolic acid (TPAC) were conducted. The analysis of secondary metabolite composition was carried out by LC-PDA-HRMS. The highest TPC and TTC were found in PAR7 (339.72 and 246.92 mg gallic acid equivalents (GAE)/g extract, respectively) and PN7 (332.11 and 252.3 mg GAE/g extract, respectively). The highest TPrC, TFC, and TPAC levels were found for PAL7 (21.28 mg catechin equivalents (CAT)/g extract, 71.85 mg rutin equivalents (RE)/g extract, and 124.18 mg caffeic acid equivalents (CAE)/g extract, respectively). LC-PDA-HRMS analysis revealed the presence of 83 compounds, including brevifolincarboxylic acid, ellagic acid, pedunculagin, agrimoniin, chlorogenic acid, astragalin, and tiliroside. Moreover, the presence of tri-coumaroyl spermidine was demonstrated for the first time in the genus Potentilla. Results of the MTT assay revealed that all tested extracts decreased the viability of both cell lines; however, a markedly stronger effect was observed in the colon cancer cells. The highest selectivity was demonstrated by PAR7, which effectively inhibited the metabolic activity of LS180 cells (IC₅₀ = 38 μg/ml), while at the same time causing the lowest unwanted effects in CCD841 CoN cells (IC₅₀ = 1,134 μg/ml). BrdU assay revealed a significant decrease in DNA synthesis in both examined cell lines in response to all investigated extracts. It should be emphasized that the tested extracts had a stronger effect on colon cancer cells than normal colon cells, and the most significant antiproliferative properties were observed in the case of PAR7 (IC₅₀ LS180 = 174 μg/ml) and PN7 (IC₅₀ LS180 = 169 μg/ml). The results of LDH assay revealed that all tested extracts were not cytotoxic against normal colon epithelial cells, whereas in the cancer cells, all compounds significantly damaged cell membranes, and the observed effect was dose-dependent. The highest cytotoxicity was observed in LS180 cells in response to PAR7, which, in concentrations ranging from 25 to 250 μg/ml, increased LDH release by 110%–1,062%, respectively. Performed studies have revealed that all Potentilla species may be useful sources for anti-colorectal cancer agents; however, additional research is required to prove this definitively.

Cuproptosis-Related genes in the prognosis of colorectal cancer and their correlation with the tumor microenvironment

Colorectal cancer (CRC) is a common tumor disease of the digestive system with high incidence and mortality. Cuproptosis has recently been found to be a new form of cell death. The clinical significance of cuproptosis-related genes (CRGs) in CRC is not clear. In this study, The Cancer Genome Atlas Colon and Rectal Cancer dataset was used to analyze the relationship between CRGs and clinical characteristics of CRC by differential expression analysis and Kaplan–Meier survival (K-M) analysis. Based on CRGs, prognosis model and risk score of CRC was constructed in COADREAD by multivariate Cox analysis. Receiver operating curves (ROC) analysis, K-M analysis and calibration analysis in GDC TCGA Colon Cancer dataset were applied to validating model. Subsequently, the relationship between risk score of CRC and immune microenvironment was analyzed by multiple immune score algorithms. Finally, we found that most CRGs were differentially expressed between tumors and normal tissues. Some CRGs were differentially expressed among different clinical characteristics. K-M analysis showed that the CRGs were related to overall survival (OS), disease-specific survival, and progression-free survival. Subsequently, DLAT and CDKN2A were identified as risk factors for OS in CRC by multivariate Cox analysis, and the risk score was established. K–M analysis showed that there was a significant difference in OS between the high-risk and low-risk groups, which were grouped by risk score median. ROC analysis showed that the risk score performs well in predicting the 1-year, 3-year and 5-year OS. Enrichment analysis showed that the differentially expressed genes between the high- and low-risk groups were enriched in immune-related signaling pathways. Further analysis showed that there were significant differences in the levels of immune cells and stromal cells between the high- and low-risk groups. The high-risk group had higher levels of immune cells and interstitial cells. At the same time, the high-risk group had a higher immune escape ability, and the predicted immune treatment response in the high-risk group was poor. In conclusion, CRGs can be used as prognostic factors in CRC and are closely related to the levels of immune cells and stromal cells in the tumor microenvironment.

Patient attitudes towards changes in colorectal cancer surveillance: An application of the Health Belief Model

OBJECTIVE

This is to determine whether health beliefs regarding colorectal cancer (CRC) screening could predict discomfort with a change to CRC surveillance proposing regular faecal immunochemical tests (FIT) instead of colonoscopy.

METHODS

Eight hundred individuals enrolled in a South Australian colonoscopy surveillance programme were invited to complete a survey on surveillance preferences. Responses were analysed using binary logistic regression predicting discomfort with a hypothetical FIT-based surveillance change. Predictor variables included constructs based on the Health Belief Model: perceived threat of CRC, perceived confidence to complete FIT and colonoscopy (self-efficacy), perceived benefits from current surveillance and perceived barriers to FIT and colonoscopy.

RESULTS

A total of 408 participants (51%) returned the survey (complete data n = 303; mean age 62 years, 52% male). Most participants (72%) were uncomfortable with FIT-based surveillance reducing colonoscopy frequency. This attitude was predicted by a higher perceived threat of CRC (OR = 1.03 [95% CI 1.01-1.04]), higher colonoscopy self-efficacy (OR = 1.34 [95% CI 1.13-1.59]) and lower perceived barriers to colonoscopy (OR = 0.92 [95% CI 0.86-0.99]).

CONCLUSIONS

Health beliefs regarding colonoscopy and perceived threat of CRC may be important to consider when changing CRC surveillance protocols. If guideline changes were introduced, these factors should be addressed to provide patients reassurance concerning the efficacy of the alternative protocol.

Cytotoxic Cyclotides from Anchietea pyrifolia, a South American Plant Species

Cyclotides are mini-proteins with potent bioactivities and outstanding potential for agricultural and pharmaceutical applications. More than 450 different plant cyclotides have been isolated from six angiosperm families. In Brazil, studies involving this class of natural products are still scarce, despite its rich floristic diversity. Herein were investigated the cyclotides from Anchietea pyrifolia roots, a South American medicinal plant from the family Violaceae. Fourteen putative cyclotides were annotated by LC-MS. Among these, three new bracelet cyclotides, anpy A-C, and the known cycloviolacins O4 (cyO4) and O17 (cyO17) were sequenced through a combination of chemical and enzymatic reactions followed by MALDI-MS/MS analysis. Their cytotoxic activity was evaluated by a cytotoxicity assay against three human cancer cell lines (colorectal carcinoma cells: HCT 116 and HCT 116 TP53^-/- and breast adenocarcinoma, MCF 7). For all assays, the IC₅₀ values of isolated compounds ranged between 0.8 and 7.3 μM. CyO17 was the most potent cyclotide for the colorectal cancer cell lines (IC₅₀, 0.8 and 1.2 μM). Furthermore, the hemolytic activity of anpy A and B, cyO4, and cyO17 was assessed, and the cycloviolacins were the least hemolytic (HD₅₀ > 156 μM). This work sheds light on the cytotoxic effects of the anpy cyclotides against cancer cells. Moreover, this study expands the number of cyclotides obtained to date from Brazilian plant biodiversity and adds one more genus containing these molecules to the list of the Violaceae family.

Cholecystectomy promotes the development of colorectal cancer by the alternation of bile acid metabolism and the gut microbiota

The incidence and mortality of colorectal cancer (CRC) have been markedly increasing worldwide, causing a tremendous burden to the healthcare system. Therefore, it is crucial to investigate the risk factors and pathogenesis of CRC. Cholecystectomy is a gold standard procedure for treating symptomatic cholelithiasis and gallstone diseases. The rhythm of bile acids entering the intestine is altered after cholecystectomy, which leads to metabolic disorders. Nonetheless, emerging evidence suggests that cholecystectomy might be associated with the development of CRC. It has been reported that alterations in bile acid metabolism and gut microbiota are the two main reasons. However, the potential mechanisms still need to be elucidated. In this review, we mainly discussed how bile acid metabolism, gut microbiota, and the interaction between the two factors influence the development of CRC. Subsequently, we summarized the underlying mechanisms of the alterations in bile acid metabolism after cholecystectomy including cellular level, molecular level, and signaling pathways. The potential mechanisms of the alterations on gut microbiota contain an imbalance of bile acid metabolism, cellular immune abnormality, acid-base imbalance, activation of cancer-related pathways, and induction of toxin, inflammation, and oxidative stress.

The Role of Biomarkers in the Management of Colorectal Liver Metastases

Simple Summary

Colorectal cancer remains one of the most significant sources of cancer-related morbidity and mortality worldwide. The liver is the most common site of metastatic spread. Multiple modalities exist to manage and potentially cure patients with metastatic colorectal cancer. However, reliable biomarkers to assist with clinical decision-making are limited. Recent advances in genomic sequencing technology have greatly expanded our knowledge of colorectal cancer carcinogenesis and significantly reduced the cost and timing of the investigation. In this article, we discuss the current utility of biomarkers in the management of colorectal cancer liver metastases.

Abstract

Surgical management combined with improved systemic therapies have extended 5-year overall survival beyond 50% among patients with colorectal liver metastases (CRLM). Furthermore, a multitude of liver-directed therapies has improved local disease control for patients with unresectable CRLM. Unfortunately, a significant portion of patients treated with curative-intent hepatectomy develops disease recurrence. Traditional markers fail to risk-stratify and prognosticate patients with CRLM appropriately. Over the last few decades, advances in molecular sequencing technology have greatly expanded our knowledge of the pathophysiology and tumor microenvironment characteristics of CRLM. These investigations have revealed biomarkers with the potential to better inform management decisions in patients with CRLM. Actionable biomarkers such as RAS and BRAF mutations, microsatellite instability/mismatch repair status, and tumor mutational burden have been incorporated into national and societal guidelines. Other biomarkers, including circulating tumor DNA and radiomic features, are under active investigation to evaluate their clinical utility. Given the plethora of therapeutic modalities and lack of evidence on timing and sequence, reliable biomarkers are needed to assist clinicians with the development of patient-tailored management plans. In this review, we discuss the current evidence regarding biomarkers for patients with CRLM.

Extracellular vesicles derived from microgreens of Raphanus sativus L. var. caudatus Alef contain bioactive macromolecules and inhibit HCT116 cells proliferation

Extracellular vesicles (EVs) are phospholipid bilayer vesicles released from cells, containing natural cargos. Microgreens of Raphanus sativus L. var. caudatus Alef were used in this study as the source of EVs. EVs were isolated by differential centrifugation. The physical properties were determined by dynamic light scattering (DLS) and electron microscopy. The biological and chemical composition were studied by Fourier-transform infrared (FTIR) microspectroscopy and high-performance liquid chromatography analysis, respectively. EVs had a median size of 227.17 and 234.90 ± 23.30 nm determined by electron microscopy and DLS, respectively with a polydispersity index of 0.293 ± 0.019. Electron microscopy indicated the intact morphology and confirmed the size. The FTIR spectra revealed that EVs are composed of proteins as the most abundant macromolecules. Using a curve-fitting analysis, β-pleated sheets were the predominant secondary structure. Notably, the micromolecular biomarkers were not detected. EVs exerted anti-cancer activity on HCT116 colon cancer over Vero normal cells with an IC₅₀ of 448.98 µg/ml and a selectivity index of > 2.23. To conclude, EVs could be successfully prepared with a simple and effective isolation method to contain nano-sized macromolecules possessing anti-cancer activity.

Chemical and Antimicrobial Characterization of Mentha piperita L. and Rosmarinus officinalis L. Essential Oils and In Vitro Potential Cytotoxic Effect in Human Colorectal Carcinoma Cells

Colorectal cancer is one of the most frequently diagnosed forms of cancer, and the therapeutic solutions are frequently aggressive requiring improvements. Essential oils (EOs) are secondary metabolites of aromatic plants with important pharmacological properties that proved to be beneficial in multiple pathologies including cancer. Mentha piperita L. (M_EO) and Rosmarinus officinalis L. (R_EO) essential oils are well-known for their biological effects (antimicrobial, antioxidant, anti-inflammatory and cytotoxic in different cancer cells), but their potential as complementary treatment in colorectal cancer is underexplored. The aim of the present study was to investigate the M_EO and R_EO in terms of chemical composition, antioxidant, antimicrobial, and cytotoxic effects in a colorectal cancer cell line—HCT 116. The gas-chromatographic analysis revealed menthone and menthol, and eucalyptol, α-pinene and L-camphor as major compounds in M_EO and R_EO respectively. M_EO exhibited potent antimicrobial activity, moderate antioxidant activity and a low cytotoxic effect in HCT 116 cells. R_EO presented a significant cytotoxicity in colorectal cancer cells and a low antimicrobial effect. The cytotoxic effect on non-cancerous cell line HaCaT was not significant for both essential oils. These results may provide an experimental basis for further research concerning the potential use of M_EO and R_EO for anticancer treatment.

Mesenchymal stem cells- derived exosomes inhibit the expression of Aquaporin-5 and EGFR in HCT-116 human colorectal carcinoma cell line

Background

Aquaporins are channel proteins, form pores in the membrane of biological cells to facilitate the transcellular and transepithelial water movement. The role of Aquaporins in carcinogenesis has become an area of interest. In this study, we aimed to investigate the effects of adipose-derived mesenchymal stem cells secreted exosomes on the expression of aquaporin 5 and EGFR genes in the HCT-116 tumor cell line.

Methods and results

Surface antigenic profile of Ad-MSCs was evaluated using specific markers. Exosomes were purified from the Ad-MSc supernatant while the quality and the shape of isolated exosomes were assessed by western blot and transmission electron microscopy (TEM) respectively. HCT-116 cells were co-cultured with MSC-conditioned medium (MSC-CM) and/or with 100 μg/ml of MSC-derived exosomes for 48 h and. Real-time PCR was carried out to determine the expression of aquaporin5 and EGFR in HCT-116. Relative expression levels were calculated using the 2^-ΔΔct method.

Our result showed that AQP5 and EGFR mRNA levels were significantly reduced in CM and/or exosomes treated HCT116 compare to the control group (P-value < 0.05).

Conclusion

The current study showed that MSC derived exosomes could inhibit expression of two important molecules involved in tumor progression. Hence it seems MSCs-derived exosomes may hold a hopeful future as drug delivery vehicles which need the furtherer investigation.

Augmented Antitumor Effect of Unripe Rubus coreanus Miquel Combined with Oxaliplatin in a Humanized PD-1/PD-L1 Knock-In Colorectal Cancer Mouse Model

Immune checkpoint inhibitors (ICIs) have been shown to be extraordinarily effective in patients with colorectal cancer (CRC). However, the current ICIs still have adverse effects and limited efficacy of ICI monotherapy. We used a natural product to overcome the vulnerability of ICIs and tried a combination therapy with oxaliplatin to enhance the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) blockade anticancer effect. In the present study, we evaluated the T cell-mediated antitumor immunity with Unripe Rubus coreanus Miquel extract (RCE), which exerts anticancer properties via PD-1/PD-L1 blockade, combined with oxaliplatin in a co-culture cell model and allograft tumor humanized PD-1 mice. We found that RCE plus oxaliplatin apparently activates hPD-1 tumor-infiltrating CD8+ T cells, resulting in elevations of released interleukin-2 (IL-2) and granzyme B (GrB), and kills hPD-L1 MC38 CRC cells. RCE plus oxaliplatin considerably reduced tumor growth in humanized PD-1/PD-L1-expressing mouse MC38 CRC allograft. Moreover, RCE plus oxaliplatin remarkably increased the infiltration of CD8+ T cells in tumor tissues, as well as increasingly produced GrB of tumor-infiltrating CD8+ T cells in the tumor microenvironment. Our study delineated combination therapy with RCE as a PD-1/PD-L1 blockade and oxaliplatin to improve the response to immune checkpoint blockade therapy in conjunction with standard chemotherapy regimens in CRC.

Fecal microbiota in patients with a stoma decreases anaerobic bacteria and alters taxonomic and functional diversities

Colorectal cancer (CRC) is one of the most common malignant diseases. Generally, stoma construction is performed following surgery for the resection of the primary tumor in patients with CRC. The association of CRC with the gut microbiota has been widely reported, and the gut microbiota is known to play an important role in the carcinogenesis, progression, and treatment of CRC. In this study, we compared the microbiota of patients with CRC between with and without a stoma using fecal metagenomic sequencing data from SCRUM-Japan MONSTAR-SCREEN, a joint industry-academia cancer research project in Japan. We found that the composition of anaerobes was reduced in patients with a stoma. In particular, the abundance of Alistipes, Akkermansia, Intestinimonas, and methane-producing archaea decreased. We also compared gene function (e.g., KEGG Orthology and KEGG pathway) and found that gene function for methane and short-chain fatty acids (SCFAs) production was underrepresented in patients with a stoma. Furthermore, a stoma decreased Shannon diversity based on taxonomic composition but increased that of the KEGG pathway. These results suggest that the feces of patients with a stoma have a reduced abundance of favorable microbes for cancer immunotherapy. In conclusion, we showed that a stoma alters the taxonomic and functional profiles in feces and may be a confounding factor in fecal microbiota analysis.

Isolation and synthesis of rocaglaol derivatives by inhibiting Wnt/β-catenin and MAPK signaling pathways against colorectal cancer

Eight rocaglaol derivatives with good cytotoxic activity (IC₅₀: 0.013 ∼ 5.82 μM) were isolated from Aglaia odorata. Then, a series of novel derivatives with modifications on C3 of rocaglaol were designed, synthesized, and screened for their antitumor activities against three tumor cell lines (HEL, MDA-MB-231, and HCT116). A total of 44 derivatives exhibited significant cytotoxic activity with IC₅₀ values lower than 1 μM. In particular, four derivatives (14, 20, 22j, and 22r) exhibited the best cytotoxic activity against HCT116 cells, with an IC₅₀ value of 70 nM. Compound 22r with relatively low toxicity against normal cells and the best cytotoxic activity against HCT116 cells was selected for further study. Subsequent cellular mechanism studies showed that compound 22r induced apoptosis and G1 cell cycle arrest in HCT116 cells. Moreover, compound 22r inhibited both the Wnt/β-catenin and MAPK signaling pathways via key proteins, such as the phosphorylation of p38 and JNK, GSK-3β, Axin-2, etc. Therefore, our present results suggest that compound 22r is a potential candidate for developing novel anti-colorectal cancer agents in the future.

Therapeutic Targeting of Cancer Stem Cells Prevents Resistance of Colorectal Cancer Cells to MEK Inhibition

Drug resistance is a leading cause for the failure of cancer treatments. Plasticity of cancer cells to acquire stem cell-like properties enables them to escape drug toxicity through different adaptive mechanisms. Eliminating cancer stem cells (CSCs) can potentially improve treatment outcomes for patients. To determine the role of CSCs in resistance of colorectal cancer cells to targeted therapies and identify treatment strategies, we treated spheroids of BRAFmut and KRASmut colorectal cancer cells with inhibitors of the mitogen-activated protein kinase pathway and studied resistance mechanisms through gene and protein expression analyses. We found that treatments activated several oncogenic pathways and expression of CSC markers CD166 and ALDH1A3. We identified a specific combination treatment using trametinib and mithramycin A to simultaneously inhibit the CSC phenotype and activities of several pathways in cancer cells. This study demonstrates the feasibility of therapeutic targeting of CSCs as a strategy to block tumorigenic activities of cancer cells.

Regulation of transforming growth factor-β signaling as a therapeutic approach to treating colorectal cancer

According to data from 2020, Slovakia has long been among the top five countries with the highest incidence rate of colorectal cancer (CRC) worldwide, and the rate is continuing to rise every year. In approximately 80% of CRC cases, allelic loss (loss of heterozygosity, LOH) occurs in the long arm of chromosome 18q. The most important genes that can be silenced by 18q LOH or mutations are small mothers against decapentaplegic homolog (SMAD) 2 and SMAD4, which are intracellular mediators of transforming growth factor (TGF)-β superfamily signals. TGF-β plays an important role in the pro-oncogenic processes, including such properties as invasion, epithelial-mesenchymal transition (commonly known as EMT), promotion of angiogenesis, and immunomodulatory effects. Several recent studies have reported that activation of TGF-β signaling is related to drug resistance in CRC. Because the mechanisms of drug resistance are different between patients in different stages of CRC, personalized treatment is more effective. Therefore, knowledge of the activation and inhibition of factors that affect the TGF-β signaling pathway is very important.

Regulation of transforming growth factor-β signaling as a therapeutic approach to treating colorectal cancer

According to data from 2020, Slovakia has long been among the top five countries with the highest incidence rate of colorectal cancer (CRC) worldwide, and the rate is continuing to rise every year. In approximately 80% of CRC cases, allelic loss (loss of heterozygosity, LOH) occurs in the long arm of chromosome 18q. The most important genes that can be silenced by 18q LOH or mutations are small mothers against decapentaplegic homolog (SMAD) 2 and SMAD4, which are intracellular mediators of transforming growth factor (TGF)-β superfamily signals. TGF-β plays an important role in the pro-oncogenic processes, including such properties as invasion, epithelial-mesenchymal transition (commonly known as EMT), promotion of angiogenesis, and immunomodulatory effects. Several recent studies have reported that activation of TGF-β signaling is related to drug resistance in CRC. Because the mechanisms of drug resistance are different between patients in different stages of CRC, personalized treatment is more effective. Therefore, knowledge of the activation and inhibition of factors that affect the TGF-β signaling pathway is very important.

Dehydroepiandrosterone Sulfate and Colorectal Cancer Risk: A Mendelian Randomization Analysis

Colorectal cancer is the third most common and second most deadly type of cancer worldwide, with approximately 1.9 million cases and 0.9 million deaths worldwide in 2020. Previous studies have shown that estrogen and testosterone hormones are associated with colorectal cancer risk and mortality. However, the potential effect of their precursor, dehydroepiandrosterone sulfate (DHEAS), on colorectal cancer risk has not been investigated. Therefore, evaluating DHEAS's effect on colorectal cancer will expand our understanding of the hormonal contribution to colorectal cancer risk. In this study, we conducted a two-sample Mendelian randomization (MR) analysis to investigate the causal effect of DHEAS on colorectal cancer. We obtained DHEAS and colorectal cancer genomewide association study (GWAS) summary statistics from the Leipzig Health Atlas and the GWAS catalog and conducted MR analyses using the TwoSampleMR R package. Our results suggest that higher DHEAS levels are causally associated with decreased colorectal cancer risk (odds ratio per unit increase in DHEAS levels z score = 0.70; 95% confidence interval [0.51, 0.96]), which is in line with previous observations in a case-control study of colon cancer. The outcome of this study will be beneficial in developing plasma DHEAS-based biomarkers in colorectal cancer. Further studies should be conducted to interpret the DHEAS-colorectal cancer association among different ancestries and populations.

METTL3 antagonizes 5‑FU chemotherapy and confers drug resistance in colorectal carcinoma

Colorectal cancer (CRC) is one of top five leading causes of cancer-associated mortalities worldwide. 5-Fluorouracil (5-FU) is the first-line chemotherapeutic drug in the treatment of CRC; however, its antineoplastic efficiency is limited due to acquired drug resistance. The regulatory mechanism underlying 5-FU chemotherapeutic response and drug resistance in CRC remains largely unknown. The present study identified that silencing of methyltransferase-like 3 (METTL3) suppressed the proliferation and migration of CRC HCT-8 cells. Using cell survival assays, flow cytometric and colony formation analyses, it was revealed that inhibition of METTL3 sensitized HCT-8 cells to 5-FU by enhancing DNA damage and inducing apoptosis in HCT-8 cells under 5-FU treatment. Furthermore, the expression of METTL3 was upregulated in 5-FU-resistant CRC cells (HCT-8R), which contributed to drug resistance through regulation of RAD51 associated Protein 1 (RAD51AP1) expression. Western blotting, immunofluorescence staining and drug sensitivity assays demonstrated that knockdown of METTL3 augmented 5-FU-induced DNA damage and overcame 5-FU-resistance in HCT-8R cells, which could be mimicked by inhibition of RAD51AP1. The present study revealed that the METTL3/RAD51AP1 axis plays an important role in the acquisition of 5-FU resistance in CRC, and targeting METTL3/RAD51AP1 may be a promising adjuvant therapeutic strategy for patients with CRC, particularly for those with 5-FU-resistant CRC.

Impact of demographic changes and screening colonoscopy on long-term projection of incident colorectal cancer cases in Germany: A modelling study

Background

Demographic aging is expected to increase the number of colorectal cancer (CRC) cases in many countries. Screening for CRC can substantially reduce the disease burden but its use has remained rather limited in Germany. We aimed to quantify the expected impact of demographic aging on the future CRC burden and the potential to reduce that burden by increased use of screening colonoscopy offers in Germany.

Methods

We obtained sex- and age-specific data on colonoscopy use from AOK, the biggest health insurance provider in Germany, and combined these with the projected demographic development and current CRC incidence rates. We estimated the number of new CRC cases until 2060, assuming screening colonoscopy use to be constant or to increase to between 1·5 and 3 times the current levels.

Findings

Ten-year screening colonoscopy utilization rates were low (<20% in both sexes in all age groups). Assuming no change in screening colonoscopy use, the overall annual caseload was predicted to increase from approximately 62,000 cases in 2020 to more than 70,000 cases by the year 2040 and more than 75,000 cases by 2050. To avoid increasing case numbers, an increase of screening colonoscopy use to more than 3 times current levels would be needed.

Interpretation

At current levels of screening use, the strong effects of the demographic aging imply that the CRC caseload will significantly increase in the decades to come. CRC screening efforts will need to be substantially increased to even maintain the current level of incident cases.

Funding

German Federal Ministry of Education and Research (grant 01GL1712).

Absolute and Functional Iron Deficiency in Colon Cancer: A Cohort Study

Background and Objectives: Iron is an essential micronutrient for many biological functions and has been found to be intimately linked to cancer biology. Although the effects of increased dietary iron consumption in the development of CRC have been previously investigated in several cohort studies, the available evidence on the involvement of iron deficiency in this process is relatively scarce. Previously published papers did not analyze specific outcomes, such as the presence of biologically aggressive histopathological characteristics, that are associated with the subtypes of iron deficiency. The purpose of this study was to investigate the connection between the development of colorectal cancer and the presence of functional iron deficiency (FID), which is defined as insufficient biological availability of iron in the presence of adequate storage reserves, or absolute iron deficiency (AID), which is defined as severely depleted iron storage levels. Materials and Methods: Our paper represents a single center registry-based cohort study. Iron levels were routinely evaluated upon diagnosis of CRC and the collected data were coupled with patient- and tumor-specific data (2018–2022). Spearman’s correlation coefficient and the chi-squared test were used to analyze the association. Results: Out of 129 patients, 75 (58.13%) were anemic. AID was identified in 26.35% of cases and FID was encountered in 51.16% of cases. A statistically significant association between FID and lymphatic invasion was encountered. An analysis of the correlation demonstrated a significant association between anemia and right-sided tumor location. Conclusions: Functional iron deficiency seems to be independently associated with lymphatic invasion. Although a statistically significant correlation with the T or N stage was not demonstrated, the analysis suggested a potential positive relationship between the presence of FID and more aggressive tumor characteristics.

Effect of lycopene as an adjuvant therapy with 5-florouracil in human colon cancer

Colon cancer (CC) is among the most frequent human cancers. Although, there is improvement in diagnostic techniques and existing treatment possibilities. Still, there is an unmet need for a novel treatment regimen that will improve the patient's quality of life. Here, the role of lycopene as an adjuvant therapy with 5-fluorouracil (5-FU) was explored in Caco2 colon cancer cells. Cells were exposed to a dose (3 µg/ml) of 5-FU and three doses (60, 90, 120 µg/ml) of lycopene either alone or as a mixture with 5-FU. Cytotoxicity, genotoxicity, oxidative stress, gene expression, and apoptotic parameters were investigated in this study. Findings showed that 5-FU or lycopene alone induced a dose-dependent increase in cytotoxicity which was slightly reduced in lycopene mixtures. Apoptotic assays showed that 5-FU induced a significant level of apoptosis but not necrosis. However, a lycopene mixture with 5-FU enhanced 5-FU triggered apoptosis and promoted necrosis. The mixtures were also shown to suppress mitochondrial membrane potential while gene expression analyses showed the induction of Bax expression upon exposure to mix 90 exhibited the highest Bax to Bcl-2 ratio and caspase 3 and 9 gene expression. Furthermore, the mixture treatment also inhibited cell migration in the wound healing assay compared to 5-FU alone. In conclusion, lycopene was found to sensitize Caco 2 cell lines to 5-FU treatment by inducing the expression of apoptotic genes. This, coupled with lycopene suppression of cytotoxicity and cell migration, indicates lycopene may be a promising candidate for adjuvant therapy involving 5-FU in CC.

Health-Related Quality of Life, Functioning, and Physical Symptoms of Adult Omani Colorectal Cancer Survivors

BACKGROUND

Colorectal (CRC) survivors often experience physical and psychological symptoms affecting their health-related quality of life (HRQoL). This study aimed to identify factors impacting HRQoL-related functioning and physical symptoms among adult Omani CRC survivors.

METHODS

A cross-sectional study of 124 adult CRC survivors was conducted at the two main oncology referral hospitals in Oman. A validated Arabic version of the European Organization for Research and Treatment of Cancer-Quality of Life Questionnaire 30 was used to collect data.

RESULTS

A total of 118 CRC survivors participated in the study (response rate: 95.2%). The mean age was 52 years and there were an equal number of male and female participants (n = 59 each; 50.0%). A total of 62 survivors (52.5%) had been diagnosed with CRC at stages III or IV. The overall score for global health was high (81.7). With regards to functioning, high mean scores were observed for domains of role (91.0) and social (90.7) functioning. In terms of symptoms, high mean scores were reported for constipation (25.4), insomnia (25.1), pain (20.1), and fatigue (18.9). Survivors under 60 years old (β=15.5, p=.004) and those with no comorbidities (β=16.0, p=.001) demonstrated better functional HRQoL. Being male was predictive of better functional HRQoL in the emotional (β=13.9, p<0.008), cognitive functioning (β=12.5, p=.013), role functioning (β=14.0, p=0.006) and physical functioning (β=17.8, p<0.001) domains.

CONCLUSIONS

Healthcare professionals in Oman should implement measures to enhance the HRQoL of CRC survivors, particularly women and those with coexisting morbidities.

Colon and Rectal Cancer Management in Low-Resource Settings

Colorectal cancer (CRC) incidence is rising in low- and middle-income countries, which also face disproportionate mortality from CRC, mainly due to diagnosis at late stages. Various challenges to CRC care exist at multiple societal levels in underserved populations. In this article, barriers to CRC care, strategies for screening, and treatment in resource-limited settings, and future directions are discussed within a global context.