Diet and nutrient factors in colorectal cancer risk

Geraniol and citral: recent developments in their anticancer credentials opening new vistas in complementary cancer therapy

About 10 million people are diagnosed with cancer each year. Globally, it is the second leading cause of death after heart disease, and by 2035, the death toll could reach 14.6 million. Several drugs and treatments are available to treat cancer, but survival rates remain low. Many studies in recent years have shown that plant-derived monoterpenes, particularly geraniol and citral, are effective against various cancers, including breast, liver, melanoma, endometrial, colon, prostate, and skin cancers. This trend has opened new possibilities for the development of new therapeutics or adjuvants in the field of cancer therapy. These monoterpenes can improve the efficacy of chemotherapy by modulating many signaling molecules and pathways within tumors. Analysis of reports on the anticancer effects published in the past 5 years provided an overview of the most important results of these and related properties. Also, the molecular mechanisms by which they exert their anticancer effects in cell and animal studies have been explained. Therefore, this review aims to highlight the scope of geraniol and citral as complementary or alternative treatment options in cancer therapy.

Global, regional, and national analyses of the burden of colorectal cancer attributable to diet low in milk from 1990 to 2019: longitudinal observational study

Background

Globally, diet low in milk is the third greatest risk factor for colorectal cancer (CRC). However, there has been a lack of detailed worldwide analysis of the burden and trends of CRC attributable to diet low in milk.

Objective

We aim to assess the spatiotemporal trends of CRC-related mortality and disability-adjusted life-years (DALYs) attributable to diet low in milk at the global, regional, and national levels from 1990 to 2019.

Methods

Data of mortality, DALYs, age-standardized mortality rate (ASMR), and age-standardized DALY rate (ASDR) of CRC attributable to diet low in milk were extracted from the Global Burden of Disease (GBD) 2019 study. The burden of CRC attributable to diet low in milk was estimated using the ASMR and ASDR, while accounting for sex, age, country, and socio-demographic index (SDI). From 1990 to 2019, the estimated annual percentage change (EAPC) was calculated to clarify the temporal trends in the ASMR and ASDR attributable to diet low in milk.

Results

In 2019, there were 166,456 (95% UI = 107,221-226,027) deaths and 3,799,297 (95% UI = 2,457,768-5,124,453) DALYs attributable to diet low in milk, accounting for 15.3 and 15.6% of CRC-related deaths and DALYs in 2019. CRC-related deaths and DALYs attributed to diet low in milk increased by 130.5 and 115.4%, from 1990 to 2019. The burden of CRC attributable to diet low in milk varied notably among regions and nations. High-middle SDI regions had the highest ASDR and ASMR of CRC linked to diet low in milk, while there was a slight downward trend high SDI regions. Among geographical regions, East Asia had the highest number of CRC-related deaths and DALYs attributable to diet low in milk. Notably, the burden of CRC was highest in males and the elderly. With coefficients of -0.36 and -0.36, the EAPC in ASMR and ASDR was significantly inversely correlated with the Human Development Index in 2019.

Conclusion

Globally, the number of CRC deaths attributable to diet low in milk has continued to increase over the last 30 years. Therefore, government and authorities should conduct education campaigns to encourage individuals to increase daily milk intake.

Is the incidence rate of colorectal cancer increasing in Mozambique?

Background

Colorectal cancer (CRC) is a significant global health concern, ranking as the third most common cancer and the second leading cause of cancer-related deaths. However, in Africa, CRC is the fifth most common invasive malignancy. Limited data hinder our understanding of the evolving burden of CRC in sub-Saharan Africa. This study explores CRC trends in Mozambique, utilising data from population-based oncological registries.

Methods

CRC data were gathered from Beira and Maputo population-based cancer registries, along with supplementary information from pathology-based and hospital-based registries. Comparative analyses were performed across different time periods, focusing on trends and epidemiological characteristics.

Results

Incidence rates of CRC in Maputo and Beira were relatively low historically. However, data from recent years showed an increase, especially in age groups above 50. Analyses from pathology-based and hospital-based registries affirmed the rising trend. The age-standardised incidence rate in Maputo (2015-2017) was 3.17 for males and 2.55 for females. Beira exhibited increasing rates between 2009 and 2020, particularly in individuals aged 50 and above.

Conclusion

The study reveals an emerging burden of CRC in Mozambique, challenging the perception of low incidence. The rising trend underscores the necessity for tailored interventions, emphasizing early diagnosis, preventive strategies, and investments in healthcare infrastructure to address the increasing CRC burden in the region.

Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk

Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.

Sex-specific associations of empirically derived dietary patterns with colorectal cancer risk in a Korean population: a case‒control study

Dietary patterns may be a crucial modifiable factor in colorectal cancer (CRC) risk. This study aimed to examine the associations of dietary patterns derived from two methods with CRC risk in Korea. In a study of 1420 CRC patients and 2840 control participants, we obtained dietary patterns by principal component analysis (PCA) and reduced rank regression (RRR) using 33 predefined food groups. The associations between dietary patterns and CRC risk were assessed using unconditional logistic regression models to calculate odds ratios (ORs) and 95% confidence intervals (CIs). We identified two similar dietary patterns, derived from PCA 1 (prudent) and RRR (healthy), characterized by higher consumption of green/yellow vegetables, light-colored vegetables, fruits, eggs, and milk in both men and women. In women, higher prudent and healthy pattern scores were significantly associated with a lower risk of CRC (prudent, ORQ4 vs. Q1 = 0.59, 95% CI 0.40-0.86, P for trend = 0.005; healthy, ORQ4 vs. Q1 = 0.62, 95% CI 0.43-0.89, P for trend = 0.007). In men, a significant inverse association between dietary pattern and risk of rectal cancer was found only for the healthy dietary pattern (ORQ4 vs. Q1 = 0.66, 95% CI 0.45-0.97, P for trend = 0.036). Compared with the dietary pattern derived by PCA, the RRR dietary pattern had a slightly stronger association with a lower risk of distal colon cancer (ORQ4 vs. Q1 = 0.58, 95% CI 0.35-0.97, P for trend = 0.025) and rectal cancer (ORQ4 vs. Q1 = 0.29, 95% CI 0.15-0.57, P for trend < 0.001) in women. Our findings suggest cancer prevention strategies focusing on a diet rich in vegetables, fruits, eggs, and milk. Moreover, the use of both PCA and RRR methods may be advantageous to explore the associations between dietary patterns and risk of CRC.

Gut microbiota and epigenetics in colorectal cancer: implications for carcinogenesis and therapeutic intervention

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. The occurrence of CRC is associated with various genetic and epigenetic mutations in intestinal epithelial cells that transform them into adenocarcinomas. There is increasing evidence indicating the gut microbiota plays a crucial role in the regulation of host physiological processes. Alterations in gut microbiota composition are responsible for initiating carcinogenesis through diverse epigenetic modifications, including histone modifications, ncRNAs and DNA methylation. This work was designed to comprehensively review recent findings to provide insight into the associations between the gut microbiota and CRC at an epigenetic level. These scientific insights can be used in the future to develop effective strategies for early detection and treatment of CRC.

Lysine demethylase 5C inhibits transcription of prefoldin subunit 5 to activate c-Myc signal transduction and colorectal cancer progression

BACKGROUND

Lysine demethylase 5C (KDM5C) has been implicated in the development of several human cancers. This study aims to investigate the role of KDM5C in the progression of colorectal cancer (CRC) and explore the associated molecular mechanism.

METHODS

Bioinformatics tools were employed to predict the target genes of KDM5C in CRC. The expression levels of KDM5C and prefoldin subunit 5 (PFDN5) in CRC cells were determined by RT-qPCR and western blot assays. The interaction between KDM5C, H3K4me3, and PFDN5 was validated by chromatin immunoprecipitation. Expression and prognostic values of KDM5C and PFDN5 in CRC were analyzed in a cohort of 72 patients. The function of KDM5C/PFDN5 in c-Myc signal transduction was analyzed by luciferase assay. Silencing of KDM5C and PFDN5 was induced in CRC cell lines to analyze the cell malignant phenotype in vitro and tumorigenic activity in nude mice.

RESULTS

KDM5C exhibited high expression, while PFDN5 displayed low expression in CRC cells and clinical CRC samples. High KDM5C levels correlated with poor survival and unfavorable clinical presentation, whereas elevated PFDN5 correlated with improved patient outcomes. KDM5C mediated demethylation of H3K4me3 on the PFDN5 promoter, suppressing its transcription and thereby enhancing the transcriptional activity of c-Myc. KDM5C knockdown in CRC cells suppressed cell proliferation, migration and invasion, epithelial-mesenchymal transition, and tumorigenic activity while increasing autophagy and apoptosis rates. However, the malignant behavior of cells was restored by the further silencing of PFDN5.

CONCLUSION

This study demonstrates that KDM5C inhibits PFDN5 transcription, thereby activating c-Myc signal transduction and promoting CRC progression.

Heme Oxygenase-1 and Its Role in Colorectal Cancer

Heme oxygenase-1 (HO-1) is an enzyme located at the endoplasmic reticulum, which is responsible for the degradation of cellular heme into ferrous iron, carbon monoxide and biliverdin-IXa. In addition to this main function, the enzyme is involved in many other homeostatic, toxic and cancer-related mechanisms. In this review, we first summarize the importance of HO-1 in physiology and pathophysiology with a focus on the digestive system. We then detail its structure and function, followed by a section on the regulatory mechanisms that control HO-1 expression and activity. Moreover, HO-2 as important further HO isoform is discussed, highlighting the similarities and differences with regard to HO-1. Subsequently, we describe the direct and indirect cytoprotective functions of HO-1 and its breakdown products carbon monoxide and biliverdin-IXa, but also highlight possible pro-inflammatory effects. Finally, we address the role of HO-1 in cancer with a particular focus on colorectal cancer. Here, relevant pathways and mechanisms are presented, through which HO-1 impacts tumor induction and tumor progression. These include oxidative stress and DNA damage, ferroptosis, cell cycle progression and apoptosis as well as migration, proliferation, and epithelial-mesenchymal transition.

Metabolomics analysis of amino acid and fatty acids in colorectal cancer patients based on tandem mass spectrometry

Metabolic differences between colorectal cancer (CRC) and NI (NI) play an important role in early diagnoses and in-time treatments. We investigated the metabolic alterations between CRC patients and NI, and identified some potential biomarkers, and these biomarkers might be used as indicators for diagnosis of CRC. In this study, there were 79 NI, 50 CRC I patients, 52 CRC II patients, 56 CRC III patients, and 52 CRC IV patients. MS-MS was used to measure the metabolic alterations. Univariate and multivariate data analysis and metabolic pathway analysis were applied to analyze metabolic data and determine differential metabolites. These indicators revealed that amino acid and fatty acids could separate these groups. Several metabolites indicated an excellent variables capability in the separation of CRC patients and NI. Ornithine, arginine, octadecanoyl carnitine, palmitoyl carnitine, adipoyl carnitine, and butyryl carnitine/propanoyl carnitine were selected to distinguish the CRC patients and NI. And methionine and propanoyl carnitine, were directly linked to different stages of CRC. Receiver operating characteristics curves and variables importance in projection both represented an excellent performance of these metabolites. In conclusion, we assessed the difference between CRC patients and NI, which supports guidelines for an early diagnosis and effective treatment.

Dietary Oncopharmacognosy as a Crosswalk between Precision Oncology and Precision Nutrition

While diet and nutrition are modifiable risk factors for many chronic and infectious diseases, their role in cancer prevention and control remains under investigation. The lack of clarity of some diet-cancer relationships reflects the ongoing debate about the relative contribution of genetic factors, environmental exposures, and replicative errors in stem cell division as determinate drivers of cancer risk. In addition, dietary guidance has often been based upon research assuming that the effects of diet and nutrition on carcinogenesis would be uniform across populations and for various tumor types arising in a specific organ, i.e., that one size fits all. Herein, we present a paradigm for investigating precision dietary patterns that leverages the approaches that led to successful small-molecule inhibitors in cancer treatment, namely understanding the pharmacokinetics and pharmacodynamics of small molecules for targeting carcinogenic mechanisms. We challenge the scientific community to refine the paradigm presented and to conduct proof-in-concept experiments that integrate existing knowledge (drug development, natural products, and the food metabolome) with developments in artificial intelligence to design and then test dietary patterns predicted to elicit drug-like effects on target tissues for cancer prevention and control. We refer to this precision approach as dietary oncopharmacognosy and envision it as the crosswalk between the currently defined fields of precision oncology and precision nutrition with the goal of reducing cancer deaths.

Identification of the effect and mechanism of Yiyi Fuzi Baijiang powder against colorectal cancer using network pharmacology and experimental validation

Background: Yiyi Fuzi Baijiang powder (YFBP) is a traditional Chinese medicine used to treat colorectal cancer, although its bioactivity and mechanisms of action have not been studied in depth yet. The study intended to identify the potential targets and signaling pathways affected by YFBP during the treatment of colorectal cancer through pharmacological network analysis and to further analyze its chemical compositions and molecular mechanisms of action. Methods: The Traditional Chinese Medicine Systems Pharmacology (TCMSP), Traditional Chinese Medicine Integrated Database (TCMID), HitPredict (HIT), and Search Tool for Interactions of Chemicals (STITCH) databases were used to screen the bioactive components and promising targets of YFBP. Targets related to colorectal cancer were retrieved from the GeneCards and Gene Ontology databases. Cytoscape software was used to construct the "herb-active ingredient-target" network. The STRING database was used to construct and analyze protein-protein interactions (PPIs). Afterward, the R packages clusterProfiler and Cytoscape Hub plug-in were used to perform Gene Ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of target genes. The results of the network pharmacological analysis were also experimentally validated. Results: In total, 33 active components and 128 target genes were screened. Among them, 46 target genes were considered potential therapeutic targets that crossed the CRC target genes. The network pharmacology analysis showed that the active components of YFBP were correlated positively with CRC inflammatory target genes such as TLR4, TNF, and IL-6. The inflammation-related signaling pathways affected by the active components included the TNF-α, interleukin-17, and toll-like receptor signaling pathways. The active ingredients of YFBP, such as luteolin, β-sitosterol, myristic acid, and vanillin, may exert anti-tumor effects by downregulating SMOX expression via anti-inflammatory signaling and regulation of the TLR4/NF-κB signaling pathway. Conclusion: In the present study, the potential active components, potential targets, and key biological pathways involved in the YFBP treatment of CRC were determined, providing a theoretical foundation for further anti-tumor research.

Role of Dairy Foods, Fish, White Meat, and Eggs in the Prevention of Colorectal Cancer: A Systematic Review of Observational Studies in 2018-2022

There is limited evidence to support the relationship between the consumption of animal-source foods other than red meat and processed meat and colorectal cancer (CRC) risk. We aimed to examine the recent available evidence from observational studies about the association between these food groups’ intake and CRC risk. For this systematic review, we searched the PubMed database for the last five years. A total of fourteen cohort studies and seven case−control studies comprising a total of >60,000 cases were included. The studies showed a consistent significant decrease in CRC risk, overall and by subsites, associated with a high consumption of total dairy products. Less strong effects associated with the consumption of any subtype of dairy product were observed. Fish consumption, overall and by subtypes (oily or non-oily and fresh or canned), showed a mild inverse association with CRC risk. The association between white meat and egg intake and CRC risk was low and based on a small number of studies; thus, these findings should be interpreted with caution. In conclusion, a high consumption of total dairy products was associated with a lower CRC risk. However, evidence for fish, white meat, and eggs and the CRC risk were not as strong.

ALDH6A1 weakens the progression of colon cancer via modulating the RAS/RAF/MEK/ERK pathway in cancer cell lines

BACKGROUND

Aldehyde dehydrogenase 6 family member A1 (ALDH6A1) is associated with multiple diseases, but its pathogenesis in colon cancer (CC) is ambiguous and needs further study so that this research explores the function of ALDH6A1 in CC.

METHODS

The level of ALDH6A1 in colon adenocarcinoma (COAD), CC tissues, and cells was measured by starBase v2.0, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot. Post transfection with overexpressed (oe)-ALDH6A1, cell biological behaviors, as well as apoptosis-, matrix metalloproteinase (MMP)-, and rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway-related markers were measured by cell function experiments, qRT-PCR, and western blot. Next, the effects of small interfering RNA targeting ALDH6A1 (si-ALDH6A1) and RAS/RAF inhibitor (MCP110) on cell biological behaviors, as well as apoptosis-, MMP-, and RAS/RAF/MEK/ERK pathway-related markers were detected again.

RESULTS

ALDH6A1 was low-expressed in COAD, CC tissues, and cells . Oe-ALDH6A1 weakened cell vitality, migration and invasionbut facilitated apoptosis; while it reduced expression levels of Bcl-2, MMP-2, MMP-9 and the RAS/RAF/MEK/ERK pathway-related markers but promoted Bax level. However, the regulation of si-ALDH6A1 on cell biological behaviors and related genes was opposite to that of oe-ALDH6A1. Moreover, MCP110 rescued the regulation of si-ALDH6A1 on cell biological behaviors, expressions of apoptosis- MMP- as well as RAS/RAF/MEK/ERK pathway-related markers. To sum up, ALDH6A1 attenuated CC progression by down-regulating the expressions of RAS/RAF/MEK/ERK pathway-related markers.

The Association of Lactose Intolerance With Colon and Gastric Cancers: Friend or Foe?

Background: Lactose intolerance (LI) appears usually in later ages when the lactase enzyme becomes deficient or absent in the small intestine. Conflicting results have been reported in the literature about the association of lactose intolerance with various gastrointestinal malignancies. Hence, our aim was to study the association between LI, colon cancer (CCa), and gastric cancer (GC) using a large database. Methods: A cross-sectional study was performed using the National Inpatient Sample (NIS) database between 2004 and 2014. We identified adult patients (18-90 years) who were diagnosed with LI (study group) using appropriate International Classification of Diseases, Ninth Revision (ICD-9) codes. The control group comprised patients who did not have a diagnosis of LI. We identified the diagnosis of CCa and GC in both study and control groups using the ICD-9 codes. Univariable and multivariable logistic regression analyses were performed to assess the association between LI, CCa, and GC. Results: The total population comprised 71,360,501 patients, of which 57,909 (0.08%) were diagnosed with LI. LI patients were older (62 vs 51 years) with more females (61.5% vs 60.1%) and less African American patients (11.8% vs 14.3%) (p <0.0001 for all). In addition, LI patients had more smoking (12.4% vs 12%) and obesity (15% vs 8.9%). On the other hand, patients in the LI group had less alcohol use (3.8% vs 4.2%) (p <0.0001). After adjusting for the age, gender, race, smoking, alcohol, obesity, and inflammatory bowel disease, the LI group had a slightly lower rate of CCa (OR 0 .974, 95%CI 0.906-1.048, p = 0.486) and a lower rate of GC (OR: 0.993, 95%CI 0.924-1.068, p =0.853); however, the results were not statistically significant. Conclusion: Patients with lactose intolerance may have a lower risk of colon and gastric cancer. However, these findings were not statistically significant. Further studies are needed to understand this association.

LINC 01436 is overexpressed in colorectal cancer and promotes cancer cell proliferation by suppressing tumor-suppressive miR-466 maturation

LINC 01436 (lncRNA) promotes lung and gastric cancers. However, it is unclear whether it participates in colorectal cancer (CRC) progression. Therefore, the study was carried out to analyze the role of LINC 01436 in CRC. LINC 01436 expressions in CRC tissues were analyzed by RT-qPCR, and its prognostic value was investigated in a follow-up study. Correlation between LINC 01436 and mature miR-466 or miR-466 precursor was analyzed by linear regression. Mature miR-466 and miR-466 precursor levels in CRC cells with LINC 01436 overexpression were studied using RT-qPCR. CRC cell proliferation was evaluated using CCK-8 assay. LINC 01436 was upregulated in CRC and predicted poor survival. LINC 01436 was inversely correlated with mature miR-466, but not miR-466 precursor. LINC 01436 was predicted to bind with miR-466 precursor. Their interaction was further verified by dual-luciferase activity assay. In CRC cells, LINC 01436 overexpression downregulated mature miR-466 but not miR-466 precursor. Cell proliferation analysis showed that LINC 01436 overexpression rescued cell proliferation reduced by miR-466. LINC 01436 is overexpressed in CRC and promotes cancer cell proliferation by suppressing miR-466 maturation.

Autophagy ATG16L1 rs2241880 impacts the colorectal cancer risk: A case-control study

Background

Despite many efforts to discover the important role of the autophagy process in the pathogenesis of colorectal cancer (CRC), the exact involved molecular mechanism still remains to be elucidated. Recently, a limited number of studies have been employed to discover the impact of autophagy genes’ variants on the development and progression of CRC. Here, we evaluated the association between two single‐nucleotide polymorphisms (SNPs) in the main components of the autophagy genes, ATG16L1 rs2241880, and ATG5 rs1475270, and the CRC risk in an Iranian population.

Methods

During this investigation, a total of 369 subjects, including 179 CRC patients and 190 non‐cancer controls have been genotyped using Tetra‐primer amplification refractory mutation system‐polymerase chain reaction (TP‐ARMS‐PCR) method.

Result

The results demonstrated that the T allele of the ATG16L1 rs2241880 was significantly associated with the increased risk of CRC in the studied population (OR 1.64, 95% CI: 1.21–2.22, p = 0.0015). Moreover, ATG16L1 rs2241880 TT genotype increased the susceptibility to CRC (OR 3.31, 95% CI: 1.64–6.69, p = 0.0008). Furthermore, a significant association was observed under the recessive and dominant inheritance models (p = 0.0015 and p = 0.017, respectively). No statistically significant differences were found in the ATG5 rs1475270 alleles and genotypes between the cases and controls.

Conclusion

The results of the present study may be helpful concerning the risk stratification in CRC patients based on the genotyping approach of autophagy pathways and emphasize the need for further investigations among different populations and ethnicities to refine our conclusions.

Polyphenols as Antitumor Agents Targeting Key Players in Cancer-Driving Signaling Pathways

Polyphenols constitute an important group of natural products that are traditionally associated with a wide range of bioactivities. These are usually found in low concentrations in natural products and are now available in nutraceuticals or dietary supplements. A group of polyphenols that include apigenin, quercetin, curcumin, resveratrol, EGCG, and kaempferol have been shown to regulate signaling pathways that are central for cancer development, progression, and metastasis. Here, we describe novel mechanistic insights on the effect of this group of polyphenols on key elements of the signaling pathways impacting cancer. We describe the protein modifications induced by these polyphenols and their effect on the central elements of several signaling pathways including PI3K, Akt, mTOR, RAS, and MAPK and particularly those affecting the tumor suppressor p53 protein. Modifications of p53 induced by these polyphenols regulate p53 gene expression and protein levels and posttranslational modifications such as phosphorylation, acetylation, and ubiquitination that influence stability, subcellular location, activation of new transcriptional targets, and the role of p53 in response to DNA damage, apoptosis control, cell- cycle regulation, senescence, and cell fate. Thus, deep understanding of the effects that polyphenols have on these key players in cancer-driving signaling pathways will certainly lead to better designed targeted therapies, with less toxicity for cancer treatment. The scope of this review centers on the regulation of key elements of cancer signaling pathways by the most studied polyphenols and highlights the importance of a profound understanding of these regulations in order to improve cancer treatment and control with natural products.

Rectal Cancer in Adolescent and Young Adult Patients: Pattern of Clinical Presentation and Case-Matched Comparison of Outcomes

BACKGROUND

Rectal cancer in adolescents and young adults (age ≤39) is increasing. Early diagnosis is a challenge in this subset of patients.

OBJECTIVE

This study aims to analyze the presentation pattern and outcomes of sporadic rectal cancer in adolescents and young adults.

DESIGN

This is a retrospective study.

SETTING

This study was conducted at 3 European tertiary centers.

PATIENTS

Data on adolescents and young adults operated on for sporadic rectal cancer (January 2008 through October 2019) were analyzed. To compare outcomes, adolescents and young adults were matched to a group of patients aged ≥40 operated on during the same period.

MAIN OUTCOME MEASURES

The primary outcomes measured were clinical presentation and long-term outcomes.

RESULTS

Sporadic rectal cancers occurred in 101 adolescents and young adults (2.4%; mean age, 33.5; range, 18-39); 51.5% were male, and a smoking habit was reported by 17.8% of patients. The rate of a family history for colorectal cancer was 25.7%, and of these patients, 24.7% were obese. Diagnosis based on symptoms was reported in 92.1% patients, and the mean time from first symptoms to diagnosis was 13.7 months. The most common symptom at diagnosis was rectal bleeding (68.8%), and 12% and 34% of the adolescents and young adults presented with locally advanced or metastatic disease at diagnosis. Consequently, 68.3% and 62.4% adolescents and young adults received neoadjuvant and adjuvant treatments. The rate of complete pathological response was 24.1%; whereas 38.6% patients had stage IV disease, and 93.1% were microsatellite stable. At a mean follow-up of 5 years, no difference in cancer-specific survival, but a lower disease-free survival was reported in adolescents and young adults (p < 0.0001) vs the matched group. Adolescents and young adults with stages I to II disease had shorter cancer-specific survival and disease-free survival (p = 0.006; p < 0.0001); with stage III disease, they had a shorter disease-free survival (p = 0.01).

LIMITATIONS

This study was limited by its observational, retrospective design.

CONCLUSIONS

The significantly delayed diagnosis in adolescents and young adults may have contributed to the advanced disease at presentation and lower disease-free survival, even at earlier stages, suggesting a higher metastatic potential than in older patients. See Video Abstract at http://links.lww.com/DCR/B537.

CNCER DE RECTO EN PACIENTES ADOLESCENTES Y ADULTOS JVENES CUADRO DE PRESENTACIN CLNICA Y COMPARACIN DE DESENLACES POR CASOS EMPAREJADOS

ANTECEDENTES:El cáncer de recto en adolescentes y adultos jóvenes (edad ≤ 39) está aumentando. El diagnóstico temprano es un desafío en este subgrupo de pacientes.OBJETIVO:Analizar el cuadro de presentación y los desenlaces en adolescentes y adultos jóvenes con cáncer de recto esporádico.DISEÑO:Estudio retrospectivo.ÁMBITO:Tres centros europeos de tercer nivel.PACIENTES:Se analizaron los datos de adolescentes y adultos jóvenes operados de cáncer de recto esporádico (enero de 2008 - octubre de 2019). Para comparar los desenlaces se emparejó a adolescentes y adultos jóvenes con un grupo de pacientes mayores de 40 años operados en el mismo período de tiempo.PRINCIPALES VARIABLES ANALIZADAS:Cuadro clínico, resultados a largo plazo.RESULTADOS:Los cánceres de recto esporádicos en adolescentes y adultos jóvenes fueron 101 (2,4%, edad media: 33,5, rango 18-39). El 51,5% eran hombres, el 17,8% de los pacientes fumaba. El 25,7% tentía antecedentes familiares de cáncer colorrectal. El 24,7% eran obesos. El diagnóstico con base en los síntomas se informó en el 92,1% de los pacientes, el tiempo promedio desde los primeros síntomas hasta el diagnóstico fue de 13,7 meses. El síntoma más común en el momento del diagnóstico fue el sangrado rectal (68,8%). 12% y 34% de adolescentes y adultos jóvenes presentaron enfermedad localmente avanzada o metastásica en el momento del diagnóstico. Por lo tanto, el 68,3% y el 62,4% de adolescentes y adultos jóvenes recibieron neoadyuvancia y adyuvancia. La tasa de respuesta patológica completa fue del 24,1%; mientras que el 38,6% estaban en estadio IV. El 93,1% eran microsatelite estable. Con una media de seguimiento de 5 años, no se observaron diferencias en la sobrevida específica del cáncer, pero se informó una menor sobrevida libre de enfermedad en adolescentes y adultos jóvenes (p <0,0001) frente al grupo emparejado. Los adolescentes y adultos jóvenes en estadios I-II tuvieron una sobrevida específica por cáncer y una sobrevida libre de enfermedad más corta (p = 0,006; p <0,0001); el estadio III tuvo una sobrevida libre de enfermedad más baja (p = 0,01).LIMITACIONES:Diseño observacional y retrospectivo.CONCLUSIONES:El diagnóstico notablemente demorado en adolescentes y adultos jóvenes puede contribuir a la presentación de una enfermedad avanzada y a una menor sobrevida libre de enfermedad, incluso en estadios más tempranas, lo cual implica un mayor potencial metastásico en comparación con pacientes mayores. Consulte Video Resumen en http://links.lww.com/DCR/B537.

The dietary carcinogen PhIP activates p53-dependent DNA damage response in the colon of CYP1A-humanized mice

Species differences in the metabolism of xenobiotics by cytochrome P450 are critical in evaluating the use of experimental animals in studying toxic compounds relevant to human diseases. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), which is produced by high-temperature cooking of fish and meat, is activated to become a carcinogen by cytochrome P4501A2 (CYP1A2) through N² -hydroxylation in humans, but is detoxified by Cyp1a2 through 4'-hydroxylation in mice. CYP1A-humanized (hCYP1A) mice, in which mouse Cyp1a is replaced with human CYP1A, show constitutive human xenobiotic metabolism by hCYP1A, thereby serving as a suitable model for studying PhIP. Previous studies have demonstrated that oral administration of PhIP induces colon tumors in hCYP1A mice; however, these studies used a super-high dose, raising concerns regarding the relevance of the mechanism to human cancer. Herein, we systematically investigated PhIP-induced colon carcinogenesis in hCYP1A mice treated with lower doses. We found that a dose 2000 times lower than that used previously, which is comparable to human daily intake levels, could induce colon tumors, albeit at a lower incidence rate. We further investigated the transcriptome changes in the colon of hCYP1A mice treated with PhIP and identified that PhIP treatment increased the expression of Bax, Btg2, Ccng1, Cdkn1a, and Trp53inp1 and decreased the expression of Igf1 and Ccnd1. Since these genes are key components of the p53-dependent DNA damage response, the altered expression patterns indicated PhIP-induced DNA damage in hCYP1A mice. Together, these results prove that hCYP1A mice are suitable for studying PhIP-induced carcinogenesis and show that PhIP is an important colorectal cancer carcinogen in human diet.

Acrolein contributes to human colorectal tumorigenesis through the activation of RAS-MAPK pathway

Colorectal cancer (CRC) is one of the most well-known malignancies with high prevalence and poor 5-year survival. Previous studies have demonstrated that a high-fat diet (HFD) is capable of increasing the odds of developing CRC. Acrolein, an IARC group 2A carcinogen, can be formed from carbohydrates, vegetable oils, animal fats, and amino acids through the Maillard reaction during the preparation of foods. Consequently, humans are at risk of acrolein exposure through the consumption of foods rich in fat. However, whether acrolein contributes to HFD-induced CRC has not been determined. In this study, we found that acrolein induced oncogenic transformation, including faster cell cycling, proliferation, soft agar formation, sphere formation and cell migration, in NIH/3T3 cells. Using xenograft tumorigenicity assays, the acrolein-transformed NIH/3T3 clone formed tumors. In addition, cDNA microarray and bioinformatics studies by Ingenuity Pathway Analysis pointed to the fact that RAS/MAPK pathway was activated in acrolein-transformed clones that contributed to colon tumorigenesis. Furthermore, acrolein-induced DNA damages (Acr-dG adducts) were higher in CRC tumor tissues than in normal epithelial cells in CRC patients. Notably, CRC patients with higher levels of Acr-dG adducts appeared to have better prognosis. The results of this study demonstrate for the first time that acrolein is important in oncogenic transformation through activation of the RAS/MAPK signaling pathway, contributing to colon tumorigenesis.

Soybean-derived gma-miR159a alleviates colon tumorigenesis by suppressing TCF7/MYC in mice

Previous reports have shown that plant-derived microRNAs (miRNAs) regulate mammalian gene expression through dietary intake. Our prior study found that gma-miR159a, which is abundant in soybean, significantly inhibited the proliferation of colon cancer cells. In the current study, dietary gma-miR159a was utilized to study its anti-colon cancer function in azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon cancer mice. Under processing conditions, gma-miR159a exhibited excellent stability in cooked soybean. In vitro, gma-miR159a suppressed the expression of the oncogene MYC downstream of the Wnt signaling pathway by targeting the TCF7 gene, significantly inhibiting the growth of colon cancer cells. The in vivo experiments showed that gma-miR159a and soybean RNA (total RNA extracted from soybean) significantly reduced tumor growth in AOM/DSS-induced colon cancer mice by gavage. This effect disappeared when anti-miR159a was present. In addition, gma-miR159a and soybean RNA significantly attenuated inflammation in colon cancer mice. These results showed that long-term dietary intake of soybean-derived gma-miR159a effectively prevented the occurrence of colon cancer and colitis, which provides novel evidence for the prevention function of soybean.

Adequacy of calcium and vitamin D reduces inflammation, β-catenin signaling, and dysbiotic Parasutterela bacteria in the colon of C57BL/6 mice fed a western-style diet

Adoption of an obesogenic diet low in calcium and vitamin D (CaD) leads to increased obesity, colonic inflammation, and cancer. However, the underlying mechanisms remain to be elucidated. We tested the hypothesis that CaD supplementation (from inadequacy to adequacy) may reduce colonic inflammation, oncogenic signaling, and dysbiosis in the colon of C57BL/6 mice fed a Western diet. Male C57/BL6 mice (4-weeks old) were assigned to 3 dietary groups for 36 weeks: (1) AIN76A as a control diet (AIN); (2) a defined rodent "new Western diet" (NWD); or (3) NWD with CaD supplementation (NWD/CaD). Compared to the AIN, mice receiving the NWD or NWD/CaD exhibited more than 0.2-fold increase in the levels of plasma leptin, tumor necrosis factor α (TNF-α) and body weight. The levels of plasma interleukin 6 (IL-6), inflammatory cell infiltration, and β-catenin/Ki67 protein (oncogenic signaling) were increased more than 0.8-fold in the NWD (but not NWD/CaD) group compared to the AIN group. Consistent with the inflammatory phenotype, colonic secondary bile acid (inflammatory bacterial metabolite) levels increased more than 0.4-fold in the NWD group compared to the NWD/CaD and AIN groups. Furthermore, the abundance of colonic Proteobacteria (e.g., Parasutterela), considered signatures of dysbiosis, was increased more than four-fold; and the α diversity of colonic bacterial species, indicative of health, was decreased by 30% in the NWD group compared to the AIN and NWD/CaD groups. Collectively, CaD adequacy reduces colonic inflammation, β-catenin oncogenic signaling, secondary bile acids, and bacterial dysbiosis in mice fed with a Western diet.

In silico development and clinical validation of novel 8 gene signature based on lipid metabolism related genes in colon adenocarcinoma

BACKGROUND

Changes in lipid metabolism pathways play a major role in colon carcinogenesis and development. Hence, we conducted a systematic analysis of lipid metabolism-related genes to explore new markers that predict the prognosis of colon adenocarcinoma (COAD).

METHODS

The non-negative Matrix Factorization (NMF) algorithm was applied to identify the molecular subtypes based on lipid metabolism-related genes. A weighted correlation network analysis (WCGNA) was used to identify co-expressed genes, and Lasso multivariate Cox analysis was performed to build a risk prognosis model. A timer database was used to analyze the immune infiltration of the gene signature and the GSCALite database was used for genome-wide analysis of the gene signature.

RESULTS

TCGA-COAD samples were divided into 3 subtypes based on lipid metabolism-related genes. 2739 genes were identified by WGCNA analysis. Finally, an 8-gene signature (RTN2, FYN, HEYL, FAM69A, FBXL5, HMGN2, LGALS4, STOX1) was constructed that demonstrated good robustness in different datasets, as well as an independent risk factor for colon cancer patients' prognosis. In addition, our model's predictive efficacy overall was higher than that of the other published models, and the 8 genes' expression analysis indicated that RTN2, HEYL, and STOX1 were all expressed highly significantly in COAD, while FAM69A, FBXL5, LGALS4, FYN and HMGN2 were expressed significantly poorly in cancer tissues, which was confirmed in immunohistochemistry. The 8 genes were expressed significantly differently in COAD immune subtypes and correlated with clinical variables. Genome-wide analysis revealed that the STOX1 mutation frequency was the highest, and genome methylation influenced HEYL, FAM69A, and STOX1 gene expression significantly; further, the expression of HEYL and FBXL5 was correlated positively with Copy number variation (CNV) and was regulated significantly by CNV in most cancers. FBXL5 was correlated significantly with austocystin d and bafilomycin and played an important role in anti-tumor and immunotherapy. The HEYL, FYN, FAM69A, and RTN2 genes' expression was associated with the EMT pathway's activation, while LGALS4 and STOX1 were associated significantly with the EMT pathway's inhibition.

CONCLUSION

This study constructed an 8-gene signature as a novel marker to predict colon cancer patients' survival.

How far along are we in revealing the connection between metformin and colorectal cancer?

Colorectal cancer (CRC) is among the most prevalent cancers worldwide, and its prevention and reduction of incidence is imperative. The presence of diabetes has been associated with a 30% increased risk of CRC, likely through the mechanism of hyperinsulinemia, which promotes tumorigenesis via the insulin receptor in the epithelium or by insulin-like growth factor pathways, inflammation, or adipokines, inducing cancer cell proliferation and cancer spread. Metformin, the first-line agent in treating type 2 diabetes, has a chemopreventive role in CRC development. Additionally, preclinical studies suggest synergistic effects of metformin with oxaliplatin in inhibiting in vitro models of colon cancer. Although preclinical studies on the post diagnostic use of metformin were promising and suggested its synergistic effects with chemotherapy, the data on the possible effects of metformin after surgery and other CRC treatment in the clinical setting are less conclusive, and randomized controlled trials are still lacking.

Untargeted Metabolomics Reveals Major Differences in the Plasma Metabolome between Colorectal Cancer and Colorectal Adenomas

Sporadic colorectal cancer is characterized by a multistep progression from normal epithelium to precancerous low-risk and high-risk adenomas to invasive cancer. Yet, the underlying molecular mechanisms of colorectal carcinogenesis are not completely understood. Within the "Metabolomic profiles throughout the continuum of colorectal cancer" (MetaboCCC) consortium we analyzed data generated by untargeted, mass spectrometry-based metabolomics using plasma from 88 colorectal cancer patients, 200 patients with high-risk adenomas and 200 patients with low-risk adenomas recruited within the "Colorectal Cancer Study of Austria" (CORSA). Univariate logistic regression models comparing colorectal cancer to adenomas resulted in 442 statistically significant molecular features. Metabolites discriminating colorectal cancer patients from those with adenomas in our dataset included acylcarnitines, caffeine, amino acids, glycerophospholipids, fatty acids, bilirubin, bile acids and bacterial metabolites of tryptophan. The data obtained discovers metabolite profiles reflecting metabolic differences between colorectal cancer and colorectal adenomas and delineates a potentially underlying biological interpretation.

Food-derived natural compounds in the management of chronic diseases via Wnt signaling pathway

Wnt signaling pathway is an evolutionarily conserved pathway that control embryonic development, adult tissue homeostasis, and pathological processes of organisms throughout life. However, dysregulation of the Wnt signaling is associated with the occurrence of chronic diseases. In comparison with the application of chemical drugs as traditional treatment for chronic diseases, dietary agents have unique advantages, such as less side effects, multiple targets, convenience in accessibility and higher acceptability in long-term intervention. In this review, we summarized current progress in manipulating the Wnt signaling using food components and its benefits in managing chronic diseases. The underlying mechanisms of bioactive food components in the management of the disease progression via the Wnt signaling was illustrated. Then, the review focused on the function of dietary pattern (which might act via combination of foods with multiple nutrients or food ingredients) on targeting Wnt signaling at multiple level. The potential caveats and challenges in developing new strategy via modulating Wnt-associated diseases with food-based agents and appropriate dietary pattern are also discussed in detail. This review shed light on the understanding of the regulatory effect of food bioactive components on chronic diseases management through the Wnt signaling, which can be expanded to other specific signaling pathway associated with disease.

Rectal cancer in young patients: incidence and outcome disparities

Background

There is an alarming rise in incidence among young patients with rectal cancer. The National Cancer Database (NCDB) and Surveillance, Epidemiology, and End Results Analysis (SEER) databases may help identify population level disparities in incidence and cancer-related outcomes.

Methods

A total of 197,178 patients within the SEER 18 registry and 221,886 patients from the NCDB database with rectal cancer were evaluated in this retrospective cohort study. The analyzed cohort consisted of young (<50), white or African American patients. Indication bias was mitigated by conducting inverse probability of treatment weighted analysis using binary logistic regression modeling to determine propensity score for being white or African American.

Results

A total of 6,144 young patients were identified from the SEER 18 registry and a total of 17,819 young patients were identified from the NCDB. From 1990 to 2016, there was a significant change in rectal cancer incidence, with a steadily increasing APC of 3.06 (P<0.05). The was no overall change in age-adjusted APC among young African American patients (APC 0.00, P=1); however, there was a significant increase among young white patients (APC 2.97, P<0.05). There was an increased incidence for both stage III and IV among young rectal cancer patients, with an age-adjusted APC of 5.35 and 3.83, respectively (P<0.05). After propensity score matching and inverse probability of treatment weighting, young African Americans had worse overall survival in both the NCDB and SEER (HR 1.1-1.3, P<0.05) databases. This disparity was also seen for cancer-specific survival (HR 1.5, P=0.002).

Conclusions

The current study adds to the growing body of literature demonstrating an alarming increase in incidence of rectal cancer among young patients. Moreover, the incidence appears to be increasing particularly among young white patients and driven by stage III disease.

Antimutagenic effect of an Asclepias subulata extract against heterocyclic aromatic amines commonly found in cooked meat and its heat stability

The antimutagenicity of an extract from the medicinal plant Asclepias subulata (ASE) against heterocyclic aromatic amines (HAAs) commonly found in cooked meat, as well as its stability to heat treatment (HT), was evaluated. HT (180 °C/3 min) had no effect on the content in ASE of the bioactive compound corotoxigenin-3-O-glucopyranoside; conversely, calotropin significantly decreased by 72%. ASE exerted antimutagenicity against PhIP, MelQ, and MelQx in TA98 and TA100 Salmonella strains, and this activity was not affected by heat, with the exception of MelQ (p < 0.05). Since HAAs can induce colorectal cancer, the thermal stability of ASE's antiproliferative effect against colorectal cancer cells was also evaluated. HT decreased (p < 0.05) the antiproliferative activity of ASE; however, the remaining activity was still strong with an IC₅₀ of 16.8 ± 2.03 µg/mL. Therefore, ASE can be used as a food ingredient to reduce the carcinogenic potential of thermally induced HAAs.

Effects of Hydroxytyrosol on Expression of Apoptotic Genes and Activity of Antioxidant Enzymes in LS180 Cells

Purpose

Colorectal cancer is the third–most commonly occurring cancer in developed countries. Hydroxytyrosol is a potent antioxidant that has several activities, such as oxidative-stress control, inhibition of cell proliferation, and induction of apoptosis. In this study, the effect of hydroxytyrosol on the expression of genes effective in apoptosis — BAX, BCL2, CASP3, P53, PPARG, and NFE2L2 — and antioxidant-enzyme activity in LS180 cells of human colorectal cancer was investigated.

Methods

The human colorectal cancer cell line LS180 was treated with different concentrations of hydroxytyrosol for 24 hours. Expression of BAX, BCL2, CASP3, NFE2L2, PPARG, and P53 was investigated using real-time PCR. The activity of antioxidant and malondialdehyde enzymes was measured by calorimetric methods.

Results

Analysis of gene expression showed that hydroxytyrosol significantly increased the expression of CASP3 and the BAX:BCL2 ratio in treatment groups compared to the control (P<0.05). Also, hydroxytyrosol significantly reduced the expression of the NFE2L2 gene (P<0.05). Calorimetric analysis showed that hydroxytyrosol increased activity of the antioxidant enzymes catalase, superoxide dismutase, and glutathione peroxidase in treatment groups significantly more than the control group and reduced thiobarbituric acid–reactive substances on an oxidative stress index (P<0.05).

Conclusion

Hydroxytyrosol may induce apoptosis in colorectal cancer cells by increasing the expression of CASP3 gene and increasing the BAX:BCL2 ratio. Also, hydroxytyrosol may increase the activity of antioxidant enzymes and reduce the proliferation of LS180 cells by changing the antioxidant-defense system in cancer cells.

Synthesis and in vitro characterization of the genotoxic, mutagenic and cell-transforming potential of nitrosylated heme

Data from epidemiological studies suggest that consumption of red and processed meat is a factor contributing to colorectal carcinogenesis. Red meat contains high amounts of heme, which in turn can be converted to its nitrosylated form, NO-heme, when adding nitrite-containing curing salt to meat. NO-heme might contribute to colorectal cancer formation by causing gene mutations and could thereby be responsible for the association of (processed) red meat consumption with intestinal cancer. Up to now, neither in vitro nor in vivo studies characterizing the mutagenic and cell transforming potential of NO-heme have been published due to the fact that the pure compound is not readily available. Therefore, in the present study, an already existing synthesis protocol was modified to yield, for the first time, purified NO-heme. Thereafter, newly synthesized NO-heme was chemically characterized and used in various in vitro approaches at dietary concentrations to determine whether it can lead to DNA damage and malignant cell transformation. While NO-heme led to a significant dose-dependent increase in the number of DNA strand breaks in the comet assay and was mutagenic in the HPRT assay, this compound tested negative in the Ames test and failed to induce malignant cell transformation in the BALB/c 3T3 cell transformation assay. Interestingly, the non-nitrosylated heme control showed similar effects, but was additionally able to induce malignant transformation in BALB/c 3T3 murine fibroblasts. Taken together, these results suggest that it is the heme molecule rather than the NO moiety which is involved in driving red meat-associated carcinogenesis.

Coffee Consumption and Colon Cancer Risk: A Meta- Epidemiological Study of Asian Cohort Studies

Objective:

A systematic review reported that coffee consumption would decrease risk of colon cancer in Asian women. But the systematic review arises the issue of duplication, so that a meta-epidemiological study was conducted.

Methods:

The selection criteria were defined that a prospective cohort follow-up study conducted to evaluate coffee consumption and risk of colon cancer in Asian and showed adjusted relative risk and its 95% confidence interval. In order to conduct meta-analysis, the highest versus lowest method was applied to extract relative risk and its 95% confidence intervals of the highest category. Random effect model was applied if I-squared value was over 50%.

Results:

After avoiding duplication, 9 cohort data were selected for meta-analysis. The summary relative risk (and their 95% confidence intervals) [I-square value] were 0.90 (95% CI: 0.79-1.03) [0.0%] in men, and 0.64 (95% CI: 0.36-1.15) [65.9%] in women, respectively.

Conclusions:

The results suggest that coffee consumption is not associated with the risk of colon cancer in Asian men and women. The findings of this study are consistent with the results of two systematic reviews conducted under the same hypothesis and selection criteria. Additional epidemiological studies are needed for the inflection of colon cancer risk as the dose of coffee increases and the difference in the protective effect by sex.

Correlation between microbes and colorectal cancer: tumor apoptosis is induced by sitosterols through promoting gut microbiota to produce short-chain fatty acids

The diversity of the bacterial community in the gut is closely related to human health. Gut microbes accomplish multiple physiological and biochemical functions. Sitosterols are a series of phytochemicals that have multiple pharmacological activities and are used as cholesterol-lowering drugs in clinical practice. In this study, we investigated the roles of bacteria and short-chain fatty acids (SCFAs) to the anti-colorectal cancer (anti-CRC) effects of sitosterols in BALB/c nude mice. Sitosterols were administered orally and gut microbiota composition and intestinal SCFAs changes were analyzed. The correlation between gut microbiota, SCFAs, and tumor apoptosis was assessed by a series of in vivo and in vitro experiments. Tumor growth in the mice was inhibited by sitosterol-treatment. Mechanistic studies revealed that sitosterol-treatment reduced the expression of PI3K/Akt, promoted the activation of Bad, decreased Bcl-xl, and enhanced cyto-c release, leading to caspase-9 and caspase-3 activation, PARP cleavage, and apoptosis. 16S rDNA analysis revealed that the diversity of microbiota, particularly phyla Bacteroidetes and Firmicutes, reduced dramatically in the gut of tumor-bearing mice, whilst treatment with sitosterols reversed these changes. The levels of SCFAs in the fecal samples of sitosterol-treated mice increased, leading to cancer cell apoptosis in vitro. Moreover, tumor apoptosis was induced after mice received a daily dose of 2 × 10⁸ CFU/0.2 mL Lactobacillus pentosus or 20 mM/0.2 mL SCFAs. Taken together, these results demonstrate that sitosterols maintain a diverse microbial environment and enrich the content of L. pentosus in the gut, leading to the production of beneficial metabolites including SCFAs that promote tumor apoptosis.

Predictors of Survival Among Colorectal Cancer Patients in a Low Incidence Area

Background

Colorectal cancer is the third most common malignancy in Saudi Arabia. The best therapeutic regimen for colorectal cancer is a matter of ongoing debate and data on its treatment in Saudi Arabia are limited.

Purpose

The objective of this study was to explore the predictors of survival and to compare the risk of mortality among colorectal cancer patients treated with different therapeutic modalities.

Patients and Methods

The study utilized data from the electronic colorectal cancer registry of a university-affiliated tertiary care hospital. The Kaplan-Meier survival analysis was used to estimate the survival rates over 36 months of follow-up across rectal and colon cancer patients as well as different sociodemographic and medical characteristics. Bivariate and multiple Cox proportional-hazards regressions were conducted to estimate the risk of mortality among rectal and colon cancer patients undergoing different treatments.

Results

The number of patients in the registry who were followed up for 36 months was 143 patients. The majority of patients had colon cancer (74.13%). Rectal cancer patients had generally better survival estimates compared to their colon cancer counterparts. Colon cancer patients treated with chemotherapy had a significantly lower risk of mortality controlling for the use of surgery, radiotherapy, and other variables including age, gender, stage of cancer, and family history of colorectal cancer (HR=0.33; P=0.03). Additionally, colon cancer patients with a family history of colorectal cancer had significantly higher risk of mortality (HR=3.40; P=0.02).

Conclusion

The findings of this study highlight the value of chemotherapy in managing colon cancer patients.

Metformin in colorectal cancer: molecular mechanism, preclinical and clinical aspects

Growing evidence showed the increased prevalence of cancer incidents, particularly colorectal cancer, among type 2 diabetic mellitus patients. Antidiabetic medications such as, insulin, sulfonylureas, dipeptyl peptidase (DPP) 4 inhibitors and glucose-dependent insulinotropic peptide (GLP-1) analogues increased the additional risk of different cancers to diabetic patients. Conversely, metformin has drawn attention among physicians and researchers since its use as antidiabetic drug exhibited beneficial effect in the prevention and treatment of cancer in diabetic patients as well as an independent anticancer drug. This review aims to provide the comprehensive information on the use of metformin at preclinical and clinical stages among colorectal cancer patients. We highlight the efficacy of metformin as an anti-proliferative, chemopreventive, apoptosis inducing agent, adjuvant, and radio-chemosensitizer in various colorectal cancer models. This multifarious effects of metformin is largely attributed to its capability in modulating upstream and downstream molecular targets involved in apoptosis, autophagy, cell cycle, oxidative stress, inflammation, metabolic homeostasis, and epigenetic regulation. Moreover, the review highlights metformin intake and colorectal cancer risk based on different clinical and epidemiologic results from different gender and specific population background among diabetic and non-diabetic patients. The improved understanding of metformin as a potential chemotherapeutic drug or as neo-adjuvant will provide better information for it to be used globally as an affordable, well-tolerated, and effective anticancer agent for colorectal cancer.

Influence of the microbiota on epigenetics in colorectal cancer

Colorectal cancer is one of the most common malignancies and is the second leading cause of cancer death worldwide. Generally, there are three categories of colorectal cancer development mechanism—genetic, epigenetic and aberrant immunological signaling pathways—all of which may be initiated by an imbalanced gut microbiota. Epigenetic modifications enable host cells to change gene expression without modifying the gene sequence. The microbiota can interact with the host genome dynamically through the interface presented by epigenetic modifications. In particular, bacterially derived short-chain fatty acids have been identified as one clear link in the interaction of the microbiota with host epigenetic pathways. This review discusses recent findings relating to the cross talk between the microbiota and epigenetic modifications in colorectal cancer.

Intake of Processed Meat and Association with Sociodemographic and Lifestyle Factors in a Representative Sample of the Swiss Population

Processed meat (PM) intake is associated with health risks, but data are lacking in Switzerland. Using national representative data from a recent menuCH Survey, we first aimed to quantify intake of PM and its subtypes, and second to investigate associations with sociodemographic and lifestyle factors by multivariable regression analysis. PM was consumed by 72% of the population, and mean daily intake was 42.7 g/day (standard error of the mean (SEM) 1.2 g/day), ranging considerably across PM subtypes: highest intake of sausages 18.1 g/day (SEM 0.7 g/day) and lowest of bacon 2.0 g/day (SEM 0.2 g/day). PM intake by women was 4.7 g/1000 kcal lower than men (95% confidence interval (CI): -6.7; -2.7) and 2.9 g/1000 kcal lower in the French- language region compared with the German region (95% CI: 2.4; 8.7). Among sociodemographic and lifestyle factors examined, BMI (obese vs. normal: 5.5 g/1000 kcal, 95% CI: 2.4; 8.7) and current smoking (vs. never smoked: 3.1 g/kcal, 95% CI: 0.6; 5.6) were independently associated with PM intake. The results are a first description of PM intake, separate from other meat types, and which identified associations with two unhealthy lifestyle factors in Switzerland. Such data will contribute to better nutritional recommendations and guidance for public health interventions.

Djulis (Chenopodium Formosanum) Prevents Colon Carcinogenesis via Regulating Antioxidative and Apoptotic Pathways in Rats

Djulis is a cereal crop rich in polyphenols and dietary fiber that may have nutraceutical activity to prevent colon cancer. This study was designed to examine the preventive effect of djulis on colon carcinogenesis in rats treated with 1,2-dimethylhydrazine (DMH). Rats were fed different AIN-93G-based diets: groups N and DMH were fed AIN-93G diet and groups LD, MD, and HD were fed AIN-93G diet containing 5, 10, and 20% djulis, respectively. All rats except for group N were injected with DMH to induce colon carcinogenesis. After 10 weeks, rats were sacrificed and colon and liver tissues were collected for analysis. The results showed that djulis-treated rats had significantly lower numbers of colonic preneoplastic lesions, aberrant crypt foci (ACF), sialomucin-producing (SIM)-ACF, and mucin-depleted foci. Djulis treatment increased superoxide dismutase and catalase activities in colon and liver. Djulis also reduced p53, Bcl-2, and proliferating cell nuclear antigen expressions and increased Bax and caspase-9 expressions. Besides, phenolic compounds and flavonoids were found rich in djulis. These results demonstrate the chemopreventive effect of djulis on carcinogen-induced colon carcinogenesis via regulating antioxidative and apoptotic pathways in rats. Djulis may have the potential to be developed as a valuable cereal product for chemoprevention of colon cancer.

The Effect of Arginine Intake on Colorectal Cancer: a Systematic Review of Literatures

Colorectal cancer (CRC) is one of the major reasons of mortality in the worldwide. There is clear evidence that some amino acids such as arginine can improve CRC and its complications. Hence, in this systematic review we evaluated the association between arginine intake and CRC improvement. We searched the PubMed, Scopus, ISI Web of Science, Cochrane library, and Google Scholar databases by using proper keywords to find the relevant literatures, published to March 2019. Nine human studies of 523 screened articles were included in present systematic review. The majority of studies have found a positive association between consumption of arginine and CRC improvement. Increased inducible nitric oxide (NO) synthase expression and subsequently increasing the NO concentration in the tumor and/or serum, after arginine intake may be responsible for these protective effects. Also, arginine consumption may reduce cell proliferation in CRC and it can enhance immune function after remove the tumor. Although the benefits of arginine consumption in CRC patients were reported in previous trials, the finding need replication in well-designed studies before final conclusion.

Dose-response meta-analysis of coffee consumption and risk of colorectal adenoma

BACKGROUND

The association between coffee and colorectal adenoma risk remains controversial. We conducted a meta-analysis of cohort and case-control studies to sum up the existing proof about this matter.

METHODS

We searched Pubmed, Medline, and Embase for studies published before 1 September 2018 on coffee consumption and colorectal adenoma in any language. The different ORs were calculated for cohort and case-control studies in this study, and we use a random-effects model to aggregate the relative risks of individual studies and conduct dose response, heterogeneity, and publication bias.

RESULTS

A total of 8 studies (6 case-control studies, 2 cohort studies) were identified, including 7090 subjects. In a summary analysis of all studies, high coffee intake (compared the highest with the lowest categories) was associated with a reduced risk of colorectal adenoma (odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.55-0.90). The results of subgroup analysis of adenoma location were similar with the pooled analysis, except for rectal adenoma. In the dose-response meta-analysis study, the estimated total odds ratio for increasing coffee consumption by 150 ml per day (about one cup) was 0.91 (95% CI = 0.87-0.95).

CONCLUSIONS

The meta-analysis demonstrates possible evidence that increased coffee intake is related to a reduced risk of colon adenoma. However, because of latent confusion and different exposure classification, this finding should be carefully considered.

Dietary Fibre Protective against Colorectal Cancer Patients in Asia: A Meta-Analysis

BACKGROUND

The association between dietary fibre and colorectal cancer risk is controversial.

AIM

This systematic review and meta-analysis were performed to determine the dietary fibre protective against colorectal cancer patients in Asia.

METHODS

The authors conducted a meta-analysis of published research articles on dietary fibre protective against colorectal cancer patients in Asia published between January 2000 and March 2019 in the online article databases of PubMed, ProQuest and EBSCO. Pooled odds ratios (OR) were calculated with fixed and random-effect models. Publication bias was visually evaluated by using funnel plots and statistically assessed through Egger's and Begg's tests. Data were processed using Review Manager 5.3 (RevMan 5.3) and Stata version 14.2 (Stata Corporation).

RESULTS

This study reviewed 405 articles. There are 10 studies conducted a systematic review and continued with Meta-analysis of relevant data with several sample 49,964 patients. The results showed dietary fibre protective against colorectal cancer patients in Asia (OR = 0.66 [95% CI 0.56-0.77, p=0.008]). There was significant publication bias for studies included in dietary fibre protective against colorectal cancer patients in Asia.

CONCLUSION

This analysis confirmed dietary fibre protective against colorectal cancer patients in Asia.

Ingestion of Non-digestible Carbohydrates From Plant-Source Foods and Decreased Risk of Colorectal Cancer: A Review on the Biological Effects and the Mechanisms of Action

The hypothesis that links the increase in the intake of plant-source foods to a decrease in colorectal cancer (CRC) risk has almost 50 years. Nowadays, systematic reviews and meta-analysis of case-control and cohort studies confirmed the association between dietary patterns and CRC risk, in which the non-digestible carbohydrates (NDC) from plant-source foods are known to play beneficial effects. However, the mechanisms behind the physicochemical properties and biological effects induced by NDC on the decrease of CRC development and progression remain not fully understood. NDC from plant-source foods consist mainly of complex carbohydrates from plant cell wall including pectin and hemicellulose, which vary among foods in structure and in composition, therefore in both physicochemical properties and biological effects. In the present review, we highlighted the mechanisms and described the recent findings showing how these complex NDC from plant-source foods are related to a decrease in CRC risk through induction of both physicochemical effects in the gastrointestinal tract, fermentation-related effects, and direct effects resulting from the interaction between NDC and cellular components including toll-like receptors and galectin-3. Studies support that the definition of the structure-function relationship-especially regarding the fermentation-related effects of NDC, as well as the direct effects of these complex carbohydrates in cells-is crucial for understanding the possible NDC anticancer effects. The dietary recommendations for the intake of NDC are usually quantitative, describing a defined amount of intake per day. However, as NDC from plant-source foods can exert effects that vary widely according to the NDC structure, the dietary recommendations for the intake of NDC plant-source foods are expected to change from a quantitative to a qualitative perspective in the next few years, as occurred for lipid recommendations. Thus, further studies are necessary to define whether specific and well-characterized NDC from plant-source foods induce beneficial effects related to a decrease in CRC risk, thereby improving nutritional recommendations of healthy individuals and CRC patients.

A missense variant in PTPN12 associated with the risk of colorectal cancer by modifying Ras/MEK/ERK signaling

BACKGROUND

The classical protein tyrosine phosphatases (PTPs) have been widely reported to be associated with various human malignancies including colorectal cancer (CRC). However, there are few comprehensive analyses of the association between the classical PTP genes and CRC risk.

METHODS

First, a bioinformatics analysis was performed to identify missense variants within the classical PTP gene family. Second, exome-wide association data and an independent population study were conducted to evaluate effects of candidate variants on CRC risk. Finally, functional assays based on signaling pathways were applied to uncover the potential pathogenic mechanism.

RESULTS

We identified that PTPN12 rs3750050 G allele presented a 19% increase the risk of CRC, with an OR of 1.19 (95% CI = 1.09-1.30, P =  1.015×10^-4) under an additive model in the combined analysis. Furthermore, biochemical assays illustrated that rs3750050 could impair the inhibitory effect of PTPN12 on Ras/MEK/ERK signaling by impeding SHC dephosphorylation, increase the expression of cyclin D1 and ultimately lead to aberrant cell proliferation, thus contributing to CRC pathogenesis.

CONCLUSION

Our study highlights that PTPN12 rs3750050 could increase CRC risk by modifying Ras/MEK/ERK signaling. This work provides a novel insight into the roles of genetic variants within PTP genes in the pathogenesis of CRC.

Functional link between plasma membrane spatiotemporal dynamics, cancer biology, and dietary membrane-altering agents

The cell plasma membrane serves as a nexus integrating extra- and intracellular components, which together enable many of the fundamental cellular signaling processes that sustain life. In order to perform this key function, plasma membrane components assemble into well-defined domains exhibiting distinct biochemical and biophysical properties that modulate various signaling events. Dysregulation of these highly dynamic membrane domains can promote oncogenic signaling. Recently, it has been demonstrated that select membrane-targeted dietary bioactives (MTDBs) have the ability to remodel plasma membrane domains and subsequently reduce cancer risk. In this review, we focus on the importance of plasma membrane domain structural and signaling functionalities as well as how loss of membrane homeostasis can drive aberrant signaling. Additionally, we discuss the intricacies associated with the investigation of these membrane domain features and their associations with cancer biology. Lastly, we describe the current literature focusing on MTDBs, including mechanisms of chemoprevention and therapeutics in order to establish a functional link between these membrane-altering biomolecules, tuning of plasma membrane hierarchal organization, and their implications in cancer prevention.

Allium vegetables are associated with reduced risk of colorectal cancer: A hospital-based matched case-control study in China

AIM

The present study aimed to investigate and identify the association between the intake of allium vegetables and colorectal cancer (CRC) in population.

METHODS

A hospital-based matched case-control study was conducted between June 2009 and November 2011 in three hospitals. Eight hundred thirty three consecutively recruited cases of CRC were frequency matched to 833 controls by age (within 2.5 years of difference), sex, and residence area (rural/urban). Demographic and dietary information were collected via face-to-face interviews using a validated food frequency questionnaire. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated by using unconditional logistic regression.

RESULTS

A decreased CRC risk was observed for the consumption of total (aORs of high total allium intake compared with low total allium intake = 0.21, 95% CI = 0.14-0.30, P trend <0.001) and several individual allium vegetables including garlic, garlic stalks, leek, onion, and spring onion (P trend <0.05). By further sex-stratified analysis, allium vegetable intake was demonstrated to be inversely associated with the risk of CRC in both men and women. However, the association of garlic intake with cancer risk was not significant among those with distal colon cancer (aOR = 0.53, 95% CI = 0.27-1.05, P trend = 0.248).

CONCLUSION

In this analysis in a Northeast Chinese population, both men and women that the consumption of allium vegetables is associated with a reduced risk of CRC, regardless of colonic tumor subsite, with the exception of garlic intake in distal colon cancer.

Effects of ursodeoxycholic acid on the gut microbiome and colorectal adenoma development

It has been previously reported that ursodeoxycholic acid (UDCA), a therapeutic bile acid, reduced risk for advanced colorectal adenoma in men but not women. Interactions between the gut microbiome and fecal bile acid composition as a factor in colorectal cancer neoplasia have been postulated but evidence is limited to small cohorts and animal studies. Using banked stool samples collected as part of a phase III randomized clinical trial of UDCA for the prevention of colorectal adenomatous polyps, we compared change in the microbiome composition after a 3-year intervention in a subset of participants randomized to oral UDCA at 8-10 mg/kg of body weight per day (n = 198) or placebo (n = 203). Study participants randomized to UDCA experienced compositional changes in their microbiome that were statistically more similar to other individuals in the UDCA arm than to those in the placebo arm. This reflected a UDCA-associated shift in microbial community composition (P < 0.001), independent of sex, with no evidence of a UDCA effect on microbial richness (P > 0.05). These UDCA-associated shifts in microbial community distance metrics from baseline to end-of-study were not associated with risk of any or advanced adenoma (all P > 0.05) in men or women. Separate analyses of microbial networks revealed an overrepresentation of Faecalibacterium prausnitzii in the post-UDCA arm and an inverse relationship between F prausnitzii and Ruminococcus gnavus. In men who received UDCA, the overrepresentation of F prausnitzii and underrepresentation of R gnavus were more prominent in those with no adenoma recurrence at follow-up compared to men with recurrence. This relationship was not observed in women. Daily UDCA use modestly influences the relative abundance of microbial species in stool and affects the microbial network composition with suggestive evidence for sex-specific effects of UDCA on stool microbial community composition as a modifier of colorectal adenoma risk.

LncRNA NEAT1 promotes colorectal cancer cell proliferation and migration via regulating glial cell-derived neurotrophic factor by sponging miR-196a-5p

Colorectal cancer (CRC) is the one of the most common malignant tumors worldwide. Recent years, widespread long non-coding RNAs (lncRNAs) have been discovered and are known to regulate gene expression in cancers. However, the roles and underlying mechanisms of lncRNA in CRC remain largely unclear. Here, we firstly revealed that repression of lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) inhibited cell proliferation and migration in HCT116 cells and overexpression of NEAT1 promoted cell proliferation and migration in SW480 cells using CCK8 assay and transwell assay. Then, we found that suppression of NEAT1 increased the miR-196a-5p expression in HCT116 cells, while elevation of NEAT1 decreased the miR-196a-5p expression in SW480 cells using qPCR assay. Furthermore, miR-196a-5p could bind to the predicted binding site of NEAT1. We then found that miR-196a-5p was involved in the role of NEAT1 in CRCs. In addition, we demonstrated that miR-196a-5p mimics inhibited the glial cell-derived neurotrophic factor (GDNF) expression in HCT116 cells and meanwhile, miR-196a-5p inhibitor promoted GDNF expression in SW480 cells using qPCR and western blot analysis. Then, we proved that miR-196a-5p exerted its function via regulating GDNF expression in CRCs. Ultimately, our study demonstrated that NEAT1 exerted its role via miR-196a-5p/GDNF axis in CRCs. In summary, this work provided the first evidence of a NEAT1/miR-196a-5p/GDNF regulatory pathway in CRC.