Genes associated with metabolic syndrome predict disease-free survival in stage II colorectal cancer patients. A novel link between metabolic dysregulation and colorectal cancer

Multifaceted Aspects of Dysfunctional Myelopoiesis in Cancer and Therapeutic Perspectives with Focus on HCC

Myelopoiesis provides for the formation and continued renewal of cells belonging primarily to the innate immune system. It is a highly plastic process that secures the response to external and internal stimuli to face acute and changing needs. Infections and chronic diseases including cancer can modulate it by producing several factors, impacting proliferation and differentiation programs. While the lymphocytic compartment has attracted major attention due to the role of adaptive immunity in anticancer immune response, in recent years, research has found convincing evidence that confirms the importance of innate immunity and the key function played by emergency myelopoiesis. Due to cancer's ability to manipulate myelopoiesis to its own advantage, the purpose of this review is to outline myelopoiesis processes within the tumor microenvironment and suggest possible therapeutic lines of research to restore the physiological functioning of the host's immune system, with a special outlook on hepatocellular carcinoma (HCC).

Mass Spectrometry Proteomics Characterization of Plasma Biomarkers for Colorectal Cancer Associated With Inflammation

Background

Colorectal cancer (CRC) prognosis is determined by the disease stage with low survival rates for advanced stages. Current CRC screening programs are mainly using colonoscopy, limited by its invasiveness and high cost. Therefore, non-invasive, cost-effective, and accurate alternatives are urgently needed.

Objective and design

This retrospective multi-center plasma proteomics study was performed to identify potential blood-based biomarkers in 36 CRC patients and 26 healthy volunteers by high-resolution mass spectrometry proteomics followed by the validation in an independent CRC cohort (60 CRC patients and 44 healthy subjects) of identified selected biomarkers.

Results

Among the 322 identified plasma proteins, 37 were changed between CRC patients and healthy volunteers and were associated with the complement cascade, cholesterol metabolism, and SERPIN family members. Increased levels in CRC patients of the complement proteins C1QB, C4B, and C5 as well as pro-inflammatory proteins, lipopolysaccharide-binding protein (LBP) and serum amyloid A4, constitutive (SAA4) were revealed for first time. Importantly, increased level of C5 was verified in an independent validation CRC cohort. Increased C4B and C8A levels were correlated with cancer-associated inflammation and CRC progression, while cancer-associated inflammation was linked to the acute-phase reactant leucine-rich alpha-2-glycoprotein 1 (LRG1) and ceruloplasmin. Moreover, a 4-protein signature including C4B, C8A, apolipoprotein C2 (APO) C2, and immunoglobulin heavy constant gamma 2 was changed between early and late CRC stages.

Conclusion

Our results suggest that C5 could be a potential biomarker for CRC diagnosis. Further validation studies will aid the application of these new potential biomarkers to improve CRC diagnosis and patient care.

Understanding the Link between Sugar and Cancer: An Examination of the Preclinical and Clinical Evidence

Per capita sugar consumption has increased in the United States to over 45 kg per year. The average person in the US currently consumes significantly more added sugar in their diet than the World Health Organization's, the American Cancer Society's, and the American Heart Association's recommendations for daily sugar consumption. Evidence from epidemiologic and preclinical studies demonstrates that excess sugar consumption can lead to development of cancer and progression of disease for those with cancer independent of the association between sugar and obesity. Human epidemiologic studies and mechanistic preclinical studies in multiple cancers support a causal link between excess sugar and cancer. Preclinical studies show that high-sucrose or high-fructose diets activate several mechanistic pathways, including inflammation, glucose, and lipid metabolic pathways. Although human studies are limited, compelling human and primate studies have explored the link between added sugar and metabolic syndrome (MetS), a risk factor for cancer. Substantial evidence suggests a causal link between MetS and added sugar, indicating important implications in the association between excess sugar consumption and cancer. Human clinical trials are needed to determine whether sugar increases cancer development and progression independently of its established role in causing obesity as well as for further exploration of the mechanisms involved.

Synergism between the metabolic syndrome components and cancer incidence: results from a prospective nested case-control study based on the China Health and Retirement Longitudinal Study (CHARLS)

OBJECTIVES

Synergism between the metabolic syndrome (MetSyn) components and cancer incidence still remains inconclusive. We aimed to investigate the unique or joint role of MetSyn components in cancer onset.

DESIGN

We conducted a prospective nested case-control study based on the China Health and Retirement Longitudinal Study.

SETTING

An ongoing national representative longitudinal study included follow-up survey of people aged 45 years and older and their partners living in private households in China.

PARTICIPANTS

There were 17 708 individuals included at baseline. A total of 306 incident cancers was identified during the follow-up. For every case, we used incidence-density sampling to match three concurrent cancer-free controls by age, sex, and both duration and calendar time of follow-up. Exposure of interest was any MetSyn diagnosis at baseline.

RESULTS

We observed elevation in cancer risk associated with MetSyn in a significant way when the number of MetSyn components was over three (OR: 1.88; 95% CI: 1.19 to 2.97), or when components contained any of elevated triglycerides (OR: 1.61; 95% CI: 1.05 to 2.48), reduced high-density lipoprotein (HDL) cholesterol (OR: 2.33; 95% CI: 1.40 to 3.86) or elevated blood pressure (OR: 1.65; 95% CI: 1.04 to 2.59) after consistent multiple adjustments in different models. The highest cancer risk was in the female reproductive system and breast cancer (OR: 4.22; 95% CI: 1.62 to 10.95) followed by digestive system (OR: 1.67; 95% CI: 1.11 to 2.53). Sensitivity analyses showed similar results after first follow-up was excluded. However, any unique MetSyn component was not associated with increased cancer risk. Interestingly, the reduced HDL was observed to be widely associated with over twofold increased risk of cancer, only when together with other MetSyn components.

CONCLUSION

MetSyn components, in a collaborative manner rather than its unique component, were associated with elevated cancer risk. Not only obesity but even subtle metabolic disturbances may give rise to cancer.

Precision medicine and metabolic syndrome

Metabolic syndrome (MetS) is one of the most important health issues around the world and a major risk factor for both type 2 diabetes mellitus (T2DM) and cardiovascular diseases. The etiology of MetS is determined by the interaction between genetic and environmental factors. Effective prevention and treatment of MetS notably decreases the risk of its complications such as diabetes, obesity, hypertension, and dyslipidemia. According to recent genome-wide association studies, multiple genes are involved in the incidence and development of MetS. The presence of particular genes which are responsible for obesity and lipid metabolism, affecting insulin sensitivity and blood pressure, as well as genes associated with inflammation, can increase the risk of MetS. These molecular markers, together with clinical data and findings from proteomic, metabolomic, pharmacokinetic, and other methods, would clarify the etiology and pathophysiology of MetS and facilitate the development of personalized approaches to the management of MetS. The application of personalized medicinebased on susceptibility identified genomes would help physicians recommend healthier lifestyles and prescribe medications to improve various aspects of health in patients with MetS. In recent years, personalized medicine by genetic testing has helped physicians determine genetic predisposition to MetS, prevent the disease by behavioral, lifestyle-related, or therapeutic interventions, and detect, diagnose, treat, and manage the disease. Clinically, personalized medicine is providing effective strategies for the prevention and treatment of MetS by reducing the time, cost, and failure rate of pharmaceutical clinical trials. It is also eliminating trial-and-error inefficiencies that inflate health care costs and undermine patient care.

Delineation of colorectal cancer ligand-receptor interactions and their roles in the tumor microenvironment and prognosis

BACKGROUND

Immunotherapies targeting ligand-receptor interactions (LRIs) are advancing rapidly in the treatment of colorectal cancer (CRC), and LRIs also affect many aspects of CRC development. However, the pattern of LRIs in CRC and their effect on tumor microenvironment and clinical value are still unclear.

METHODS

We delineated the pattern of LRIs in 55,539 single-cell RNA sequencing (scRNA-seq) samples from 29 patients with CRC and three bulk RNA-seq datasets containing data from 1411 CRC patients. Then the influence of tumor microenvironment, immunotherapy and prognosis of CRC patients were comprehensively investigated.

RESULTS

We calculated the strength of 1893 ligand-receptor pairs between 25 cell types to reconstruct the spatial structure of CRC. We identified tumor subtypes based on LRIs, revealed the relationship between the subtypes and immunotherapy efficacy and explored the ligand-receptor pairs and specific targets affecting the abundance of tumor-infiltrating lymphocytes. Finally, a prognostic model based on ligand-receptor pairs was constructed and validated.

CONCLUSION

Overall, through the comprehensive and in-depth investigation of the existing ligand-receptor pairs, this study provides new ideas for CRC subtype classification, a new risk screening tool for CRC patients, and potential ligand-receptor pair targets and pathways for CRC therapy.

Metabolic syndrome is a predictor of all site and liver-specific recurrence following primary resection of colorectal cancer: Prospective cohort study of 1006 patients

INTRODUCTION

Large epidemiological studies have demonstrated the link between metabolic syndrome and cancer development, including colorectal cancer. However, the influence of metabolic syndrome on disease progression is less well studied, particularly in the post-surgical setting. This study investigates the effect of metabolic syndrome on colorectal cancer recurrence (all-site and liver-specific) after curative surgery for Stage I-III disease.

MATERIALS AND METHODS

Consecutive patients who underwent curative resection for Stage I-III colorectal cancer in a single UK centre were prospectively recruited. Disease-free and overall survival with metabolic syndrome as a factor, were determined using the Kaplan-Meier technique. Hazard ratios for all-site and liver-specific recurrence were determined using univariable and multivariable Cox-regression models.

RESULTS

1006 patients were recruited and followed up for a median of 50 months (IQR 30-67). 177 patients (17.6%) met the criteria for metabolic syndrome. 245 patients (25.4%) developed recurrence, 161 (16.0%) of these had liver recurrence. The presence of metabolic syndrome was associated with a reduction in disease-free survival from 69 to 58 months (p < 0.001) and overall survival from 74 to 61 months (p < 0.001). Metabolic syndrome was an independent predictor of all-site (HR 1.76; p < 0.001) and liver-specific (HR 1.74; p = 0.01) recurrence.

CONCLUSION

Metabolic syndrome is a predictor of all-site and liver-specific recurrence after primary resection of stage I-III colorectal cancer.

Prognosis Prediction for Colorectal Cancer Patients: A Risk Score Based on The Metabolic-Related Genes

Risk assessment has high prognostic value in patients with colorectal cancer (CRC), and the use of proper models is an effective approach frequently used to evaluate cancer progression for further treatment plans. Alterations in metabolism are confirmed to be a significant feature of tumor cells and have been an intense focus in disease research. Here, we mined the genes that were differentially expressed in CRC tissues compared to paired normal samples from a public database and then constructed a novel assessment system for the prognosis of patients based on the value of a risk score considering the expression status of metabolism-related genes after screening. The score successfully stratified patients by risk and was externally verified in our study. Moreover, we built a nomogram combining the score and clinical parameters to predict patient survival using a visual method. The results suggested that the risk score was well fit and could provide assistance for the individual treatment of CRC patients in the clinic.

Risk of Death in Colorectal Cancer Patients with Multi-morbidities of Metabolic Syndrome: A Retrospective Multicohort Analysis

Purpose

The prevalence of multi-morbidities with colorectal cancer (CRC) is known to be increasing. Particularly prognosis of CRC patients co-diagnosed with metabolic syndrome (MetSyn) was largely unknown. We aimed to examine the death risk of CRC patients according to the multiple MetSyn morbidities.

Materials and Methods

We identified CRC patients with MetSyn from the electronic medical records (EMR) systems in five independent hospitals during 2006–2011. Information on deaths was jointly retrieved from EMR, cause of death registry and chronic disease surveillance as well as study-specific questionnaire. Cox proportional hazards regression was used to calculate the overall and CRC-specific hazards ratios (HR) comparing MetSyn CRC cohort with reference CRC cohort.

Results

A total of 682 CRC patients in MetSyn CRC cohort were identified from 24 months before CRC diagnosis to 1 month after. During a median follow-up of 92 months, we totally observed 584 deaths from CRC, 245 being in MetSyn cohort and 339 in reference cohort. Overall, MetSyn CRC cohort had an elevated risk of CRC-specific mortality (HR, 1.49; 95% confidence interval [CI], 1.07 to 1.90) and overall mortality (HR, 1.43; 95% CI, 1.09 to 1.84) compared to reference cohort after multiple adjustment. Stratified analyses showed higher mortality risk among women (HR, 1.87; 95% CI, 1.04 to 2.27) and specific components of MetSyn. Notably, the number of MetSyn components was observed to be significantly related to CRC prognosis.

Conclusion

Our findings supported that multi-morbidities of MetSyn associated with elevated death risk after CRC. MetSyn should be considered as an integrated medical condition more than its components in CRC prognostic management.

Saponin-Rich Extracts and Their Acid Hydrolysates Differentially Target Colorectal Cancer Metabolism in the Frame of Precision Nutrition

Saponins or their aglycone form, sapogenin, have recently gained interest as bioactive agents due to their biological activities, their antitumoral effects being among them. Metabolic reprogramming has been recognized as a hallmark of cancer and, together with the increased aerobic glycolysis and glutaminolysis, the altered lipid metabolism is considered crucial to support cancer initiation and progression. The purpose of this study was to assess and compare the inhibitory effects on colorectal cancer cell lines of saponin-rich extracts from fenugreek and quinoa (FE and QE, respectively) and their hydrolyzed extracts as sapogenin-rich extracts (HFE and HQE, respectively). By mean of the latest technology in the analysis of cell bioenergetics, we demonstrate that FE and HFE diminished mitochondrial oxidative phosphorylation and aerobic glycolysis; meanwhile, quinoa extracts did not show relevant activities. Distinct molecular mechanisms were identified for fenugreek: FE inhibited the expression of TYMS1 and TK1, synergizing with the chemotherapeutic drug 5-fluorouracil (5-FU); meanwhile, HFE inhibited lipid metabolism targets, leading to diminished intracellular lipid content. The relevance of considering the coexisting compounds of the extracts or their hydrolysis transformation as innovative strategies to augment the therapeutic potential of the extracts, and the specific subgroup of patients where each extract would be more beneficial, are discussed in the frame of precision nutrition.

Implications of metabolism-driven myeloid dysfunctions in cancer therapy

Immune homeostasis is maintained by an adequate balance of myeloid and lymphoid responses. In chronic inflammatory states, including cancer, this balance is lost due to dramatic expansion of myeloid progenitors that fail to mature to functional inflammatory neutrophils, macrophages, and dendritic cells (DCs), thus giving rise to a decline in the antitumor effector lymphoid response. Cancer-related inflammation orchestrates the production of hematopoietic growth factors and cytokines that perpetuate recruitment and activation of myeloid precursors, resulting in unresolved and chronic inflammation. This pathologic inflammation creates profound alterations in the intrinsic cellular metabolism of the myeloid progenitor pool, which is amplified by competition for essential nutrients and by hypoxia-induced metabolic rewiring at the tumor site. Therefore, persistent myelopoiesis and metabolic dysfunctions contribute to the development of cancer, as well as to the severity of a broad range of diseases, including metabolic syndrome and autoimmune and infectious diseases. The aims of this review are to (1) define the metabolic networks implicated in aberrant myelopoiesis observed in cancer patients, (2) discuss the mechanisms underlying these clinical manifestations and the impact of metabolic perturbations on clinical outcomes, and (3) explore new biomarkers and therapeutic strategies to restore immunometabolism and differentiation of myeloid cells towards an effector phenotype to increase host antitumor immunity. We propose that the profound metabolic alterations and associated transcriptional changes triggered by chronic and overactivated immune responses in myeloid cells represent critical factors influencing the balance between therapeutic efficacy and immune-related adverse effects (irAEs) for current therapeutic strategies, including immune checkpoint inhibitor (ICI) therapy.

RNA processing genes characterize RNA splicing and further stratify colorectal cancer

Objectives

Due to the limited evaluation of the prognostic value of RNA processing genes (RPGs), which are regulators of alternative splicing events (ASEs) that have been shown to be associated with tumour progression, this study sought to determine whether colorectal cancer (CRC) could be further stratified based on the expression pattern of RPGs.

Materials and Methods

The gene expression profiles of CRCs were collected from TCGA (training set) and three external validation cohorts, representing 1060 cases totally. Cox regression with least absolute shrinkage and selection operator (LASSO) penalty was used to develop an RNA processing gene index (RPGI) risk score. Kaplan‐Meier curves, multivariate Cox regression and restricted mean survival (RMS) analyses were harnessed to evaluate the prognostic value of the RPGI.

Results

A 22‐gene RPGI signature was developed, and its risk score served as a strong independent prognostic factor across all data sets when adjusted for major clinical variables. Moreover, ASEs for certain genes, such as FGFR1 and the RAS oncogene family, were significantly correlated with RPGI. Expression levels of genes involved in splicing‐ and tumour‐associated pathways were significantly correlated with RPGI score. Furthermore, a combination of RPGI with age and tumour stage resulted in significantly improved prognostic accuracy.

Conclusions

Our findings highlighted the prognostic value of RPGs for risk stratification of CRC patients and provide insights into specific ASEs associated with the development of CRC.

Revelation of Proteomic Indicators for Colorectal Cancer in Initial Stages of Development

Background: Colorectal cancer (CRC) at a current clinical level is still hardly diagnosed, especially with regard to nascent tumors, which are typically asymptotic. Searching for reliable biomarkers of early diagnosis is an extremely essential task. Identification of specific post-translational modifications (PTM) may also significantly improve net benefits and tailor the process of CRC recognition. We examined depleted plasma samples obtained from 41 healthy volunteers and 28 patients with CRC at different stages to conduct comparative proteome-scaled analysis. The main goal of the study was to establish a constellation of protein markers in combination with their PTMs and semi-quantitative ratios that may support and realize the distinction of CRC until the disease has a poor clinical manifestation. Results: Proteomic analysis revealed 119 and 166 proteins for patients in stages I–II and III–IV, correspondingly. Plenty of proteins (44 proteins) reflected conditions of the immune response, lipid metabolism, and response to stress, but only a small portion of them were significant (p < 0.01) for distinguishing stages I–II of CRC. Among them, some cytokines (Clusterin (CLU), C4b-binding protein (C4BP), and CD59 glycoprotein (CD59), etc.) were the most prominent and the lectin pathway was specifically enhanced in patients with CRC. Significant alterations in Inter-alpha-trypsin inhibitor heavy chains (ITIH1, ITIH2, ITIH3, and ITIH4) levels were also observed due to their implication in tumor growth and the malignancy process. Other markers (Alpha-1-acid glycoprotein 2 (ORM2), Alpha-1B-glycoprotein (A1BG), Haptoglobin (HP), and Leucine-rich alpha-2-glycoprotein (LRG1), etc.) were found to create an ambiguous core involved in cancer development but also to exactly promote tumor progression in the early stages. Additionally, we identified post-translational modifications, which according to the literature are associated with the development of colorectal cancer, including kininogen 1 protein (T327-p), alpha-2-HS-glycoprotein (S138-p) and newly identified PTMs, i.e., vitamin D-binding protein (K75-ac and K370-ac) and plasma protease C1 inhibitor (Y294-p), which may also contribute and negatively impact on CRC progression. Conclusions: The contribution of cytokines and proteins of the extracellular matrix is the most significant factor in CRC development in the early stages. This can be concluded since tumor growth is tightly associated with chronic aseptic inflammation and concatenated malignancy related to loss of extracellular matrix stability. Due attention should be paid to Apolipoprotein E (APOE), Apolipoprotein C1 (APOC1), and Apolipoprotein B-100 (APOB) because of their impact on the malfunction of DNA repair and their capability to regulate mTOR and PI3K pathways. The contribution of the observed PTMs is still equivocal, but a significant decrease in the likelihood between modified and native proteins was not detected confidently.

Prediction of Target Genes and Pathways Associated With Cetuximab Insensitivity in Colorectal Cancer

Background:

Cetuximab has been regularly added to the treatments for metastatic colorectal cancer worldwide. However, due to its therapeutic insensitivity and underlying mechanisms being largely unknown, the clinical implementation of cetuximab in colorectal cancer remains limited.

Methods:

The gene expression profile GSE56386 was retrieved from the Gene Expression Omnibus database. Differentially expressed genes were identified between cetuximab-responsive patients and nonresponders, annotated by gene ontology, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and further analyzed by protein–protein interaction networks. The integrative prognostic analysis was based on The Cancer Genome Atlas and PrognoScan.

Results:

1350 differentially expressed genes were identified with 298 upregulated and 1052 downregulated. Epidermis development, the cornified envelope, calcium ion binding, and amoebiasis were enriched in upregulated genes while digestion, the apical part of the cell, the 3′,5′-cyclic-adenosine monophosphate phosphodiesterase activity and pancreatic secretion were found enriched in downregulated genes. The top 10 hub genes were identified, including epithermal growth factor, G-protein subunit β 5, G-protein subunit γ 4, fibroblast growth factor 2, B-cell lymphoma protein 2, acetyl-coenzyme A carboxylase β, KIT proto-oncogene receptor tyrosine kinase, adenylate cyclase 4, neuropeptide Y, and neurotensin. The hub genes exhibited distinct correlations in cetuximab-treated and untreated genomic profiles (GSE56386, GSE5851 and GSE82236). The highest correlation was found between B-cell lymphoma protein 2 and acetyl-coenzyme A carboxylase β in GSE56386. The mRNA expression of hub genes was further validated in the genomic profile GSE65021. Furthermore, B-cell lymphoma protein 2 and acetyl-coenzyme A carboxylase β also exhibited highest degrees among the hub genes correlation networks based on The Cancer Genome Atlas. Both B-cell lymphoma and acetyl-coenzyme A carboxylase β were not independent prognostic factors for colorectal cancer in univariate and multivariate Cox analysis. However, integrative survival analysis indicated that B-cell lymphoma protein 2 was associated with favorable prognosis (hazard ratio = 0.62, 95% confidence interval, 0.30-0.95, P = .024).

Discussion:

This in silico analysis provided a feasible and reliable strategy for systematic exploration of insightful target genes, pathways and mechanisms underlying the cetuximab insensitivity in colorectal cancer. B-cell lymphoma protein 2 was associated with favorable prognosis.

Metabolic syndrome and cancer: "The common soil hypothesis"

Metabolic syndrome (MetS) and cancer share many modifiable risk factors including age, genetic factors, obesity, physical inactivity, unhealthy diet, alcohol, smoking, endocrine disruptors exposure, circadian clock disturbances, and air pollution. MetS is closely linked to cancer, as it increases cancer risk and cancer-related mortality; moreover, cancer survivors have an increased risk of MetS. Elucidating the mechanisms linking MetS to cancer is important to prevent or delay these two conditions. Possible mechanisms explaining the relationship between MetS and cancer include hyperinsulinemia and alterations of insulin-like growth factor system, chronic subclinical inflammation, abnormalities in sex hormones metabolism and adipokines, hyperglicemia, alterations in both gene expression and hormonal profile by endocrine disruptors and air pollution, desynchronization of circadian clock. The common soil hypothesis claims that MetS may be considered a surrogate marker for dietary risk factors of cancer, and a warning sign for susceptible individuals exposed to an unhealthy diet. The common soil hypothesis and the clepsydra of foods represent a theoretical substrate to preventive intervention strategies against the pandemics of MetS and cancer: adherence to healthy dietary patterns is associated with a reduced risk of MetS, and improvement of the quality of diet is consistently associated with a reduction in cancer-related mortality.

Identification of A Gene Set Associated with Colorectal Cancer in Microarray Data Using The Entropy Method

Objective

We sought to apply Shannon’s entropy to determine colorectal cancer genes in a microarray dataset.

Materials and Methods

In the retrospective study, 36 samples were analysed, 18 colorectal carcinoma and 18 paired normal tissue samples. After identification of the gene fold-changes, we used the entropy theory to identify an effective gene set. These genes were subsequently categorised into homogenous clusters.

Results

We assessed 36 tissue samples. The entropy theory was used to select a set of 29 genes from 3128 genes that had fold-changes greater than one, which provided the most information on colorectal cancer. This study shows that all genes fall into a cluster, except for the R08183 gene.

Conclusion

This study has identified several genes associated with colon cancer using the entropy method, which were not detected by custom methods. Therefore, we suggest that the entropy theory should be used to identify genes associated with cancers in a microarray dataset.

Sex hormone-binding globulin (SHBG) is a potential early diagnostic biomarker for gastric cancer

The use of blood plasma biomarkers in gastric cancer (GC) management is limited due to a lack of reliable biomarkers. An LC-MS/MS assay and a bioinformatic analysis were performed to identify blood plasma biomarkers in a GC discovery cohort. The data obtained were verified and validated by western blotting and an ELISA in an independent study cohort. A label-free quantification analysis of the MS data using PEAKS7 software found that four plasma proteins of apolipoprotein C-1, gelsolin, sex hormone-binding globulin (SHBG), and complement component C4-A were significantly overexpressed in GC patients. A western blot assay of these plasma proteins showed that only SHBG was consistently overexpressed in the patient group. ELISA measurement of SHBG blood plasma levels confirmed that the patient group had significantly higher SHBG levels than the control group. SHBG levels in the patient group remained significantly higher after being stratified by gender, age, and disease stage. These findings show that LC-MS/MS is powerful and highly sensitive for plasma biomarker discovery, and SHBG could be a potential plasma biomarker for GC management.

Energy sensing pathways: Bridging type 2 diabetes and colorectal cancer?

The recently rapid increase of obesity and type 2 diabetes mellitus has caused great burden to our society. A positive association between type 2 diabetes and risk of colorectal cancer has been reported by increasing epidemiological studies. The molecular mechanism of this connection remains elusive. However, type 2 diabetes may result in abnormal carbohydrate and lipid metabolism, high levels of circulating insulin, insulin growth factor-1, and adipocytokines, as well as chronic inflammation. All these factors could lead to the alteration of energy sensing pathways such as the AMP activated kinase (PRKA), mechanistic (mammalian) target of rapamycin (mTOR), SIRT1, and autophagy signaling pathways. The resulted impaired SIRT1 and autophagy signaling pathway could increase the risk of gene mutation and cancer genesis by decreasing genetic stability and DNA mismatch repair. The dysregulated mTOR and PRKA pathway could remodel cell metabolism during the growth and metastasis of cancer in order for the cancer cell to survive the unfavorable microenvironment such as hypoxia and low blood supply. Moreover, these pathways may be coupling metabolic and epigenetic alterations that are central to oncogenic transformation. Further researches including molecular pathologic epidemiologic studies are warranted to better address the precise links between these two important diseases.

3'UTR Polymorphism in ACSL1 Gene Correlates with Expression Levels and Poor Clinical Outcome in Colon Cancer Patients

Strong evidence suggests that lipid metabolism (LM) has an essential role in tumor growth to support special energetic and structural requirements of tumor cells. Recently, overexpression of LM-related genes, apolipoproteins related to metabolic syndrome, and ACSL/SCD network involved in fatty acid activation have been proposed as prognostic markers of colon cancer (CC). Furthermore, activation of this latter lipid network has been recently demonstrated to confer invasive and stem cell properties to tumor cells promoting tumor aggressiveness and patient relapse. With the aim of elucidating whether any genetic variation within these genes could influence basal expression levels and consequent susceptibility to relapse, we genotype, in 284 CC patients, 57 polymorphisms located in the 7 genes of these lipid networks previously associated with worse clinical outcome of CC patients (ABCA1, ACSL1, AGPAT1, APOA2, APOC1, APOC2 and SCD), some of them related to CC aggressiveness. After adjusting with clinical confounding factors and multiple comparisons, an association between genotype and disease-free survival (DFS) was shown for rs8086 in 3'-UTR of ACSL1 gene (HR 3.08; 95% CI 1.69-5.63; adjusted p = 0.046). Furthermore, the risk T/T genotype had significantly higher ACSL1 gene expression levels than patients carrying C/T or C/C genotype (means = 5.34; 3.73; 2.37 respectively; p-value (ANOVA) = 0.019), suggesting a functional role of this variant. Thus, we have identified a "risk genotype" of ACSL1 gene that confers constitutive high levels of the enzyme, which is involved in the activation of fatty acids through conversion to acyl-CoA and has been recently related to increased invasiveness of tumor cells. These results suggest that rs8086 of ACSL1 could be a promising prognostic marker in CC patients, reinforcing the relevance of LM in the progression of CC.

A link between lipid metabolism and epithelial-mesenchymal transition provides a target for colon cancer therapy

The alterations in carbohydrate metabolism that fuel tumor growth have been extensively studied. However, other metabolic pathways involved in malignant progression, demand further understanding. Here we describe a metabolic acyl-CoA synthetase/stearoyl-CoA desaturase ACSL/SCD network causing an epithelial-mesenchymal transition (EMT) program that promotes migration and invasion of colon cancer cells. The mesenchymal phenotype produced upon overexpression of these enzymes is reverted through reactivation of AMPK signaling. Furthermore, this network expression correlates with poorer clinical outcome of stage-II colon cancer patients. Finally, combined treatment with chemical inhibitors of ACSL/SCD selectively decreases cancer cell viability without reducing normal cells viability. Thus, ACSL/SCD network stimulates colon cancer progression through conferring increased energetic capacity and invasive and migratory properties to cancer cells, and might represent a new therapeutic opportunity for colon cancer treatment.

Preoperative metabolic syndrome and prognosis after radical resection for colorectal cancer: The Fujian prospective investigation of cancer (FIESTA) study

This prospective study sought to investigate the prediction of preoperative metabolic syndrome and its components for the risk of colorectal cancer (CRC) mortality by analyzing a subset of data from the ongoing Fujian prospective investigation of cancer (FIESTA) study. In total, 1,318 CRC patients who received radical resection were consecutively enrolled between January 2000 and December 2008. The median follow-up time was 58.6 months, with 412 deaths from CRC. The CRC patients with metabolic syndrome had significantly shorter median survival time (MST) than those without (50.9 vs. 170.3 months, p < 0.001). Among four components of metabolic syndrome, hyperglycemia was the strongest predictor and its presence was associated with shorter MST than its absence (44.4 vs. 170.3 months, p < 0.001). Moreover, the complication of metabolic syndrome in CRC patients was associated with a 2.98-fold increased risk of CRC mortality (hazard ratio [HR] = 2.98, 95% confidence interval [CI]: 2.40-3.69, p < 0.001) after adjusting for confounding factors. The magnitude of this association was especially potentiated in CRC patients with tumor-node-metastasis stage I/II (HR = 3.94, 95% CI: 2.65-5.85, p < 0.001), invasion depth T1/T2 (HR = 5.41, 95% CI: 2.54-11.50, p < 0.001), regional lymph node metastasis N0 (HR = 4.06, 95% CI: 2.85-5.80, p < 0.001) and negative distant metastasis (HR = 3.23, 95% CI: 2.53-4.12, p < 0.001). Further survival tree analysis reinforced the prognostic capability of fasting blood glucose in CRC survival. Our findings convincingly demonstrated that preoperative metabolic syndrome, especially hyperglycemia, was a robust predictor for CRC mortality, and the protection was more obvious in patients with Stage I/II.

Impact of metabolic syndrome on the survival of Chinese patients with resectable esophageal squamous cell carcinoma

Metabolic syndrome (MetS) is associated with the risk of esophageal squamous cell carcinoma (ESCC). However, the impact of MetS on survival has not been evaluated. A retrospective review was performed on 596 consecutive Chinese patients with esophageal squamous cell carcinoma who received surgery between January 2005 and October 2007. The clinical data and pretreatment information related to MetS were reviewed. The impact of MetS on overall survival (OS) was estimated by Kaplan-Meier and Cox proportional hazards analyses. MetS was a significant and independent predictor for better survival in patients with resectable ESCC. The 3-year OS and 5-year OS for patients with and without MetS were 75.0% versus 57.8% and 65.1% versus 44.6%, respectively (P = 0.005 in the univariate analysis, P = 0.010 in multivariate analysis). However, there was no apparent influence of any single component of MetS on OS. The other independent prognostic factors identified in the univariate analysis included the following: gender, smoking status, alcohol use, the extent of radical surgical resection, T and N stage, and tumor differentiation. The results of the multivariate analysis included the extent of radical surgery resection, T and N stage, and tumor differentiation. MetS was also associated with greater tumor cell differentiation (P = 0.036). There was no association found between MetS status and postoperative complications. MetS is an independent prognostic factor for OS in patients with ESCC and is associated with better tumor cell differentiation.

ColoLipidGene: signature of lipid metabolism-related genes to predict prognosis in stage-II colon cancer patients

Lipid metabolism plays an essential role in carcinogenesis due to the requirements of tumoral cells to sustain increased structural, energetic and biosynthetic precursor demands for cell proliferation. We investigated the association between expression of lipid metabolism-related genes and clinical outcome in intermediate-stage colon cancer patients with the aim of identifying a metabolic profile associated with greater malignancy and increased risk of relapse. Expression profile of 70 lipid metabolism-related genes was determined in 77 patients with stage II colon cancer. Cox regression analyses using c-index methodology was applied to identify a metabolic-related signature associated to prognosis. The metabolic signature was further confirmed in two independent validation sets of 120 patients and additionally, in a group of 264 patients from a public database. The combined analysis of these 4 genes, ABCA1, ACSL1, AGPAT1 and SCD, constitutes a metabolic-signature (ColoLipidGene) able to accurately stratify stage II colon cancer patients with 5-fold higher risk of relapse with strong statistical power in the four independent groups of patients. The identification of a group of 4 genes that predict survival in intermediate-stage colon cancer patients allows delineation of a high-risk group that may benefit from adjuvant therapy, and avoids the toxic and unnecessary chemotherapy in patients classified as low-risk group.

Genes associated with metabolic syndrome predict disease-free survival in stage II colorectal cancer patients. A novel link between metabolic dysregulation and colorectal cancer

Studies have recently suggested that metabolic syndrome and its components increase the risk of colorectal cancer. Both diseases are increasing in most countries, and the genetic association between them has not been fully elucidated. The objective of this study was to assess the association between genetic risk factors of metabolic syndrome or related conditions (obesity, hyperlipidaemia, diabetes mellitus type 2) and clinical outcome in stage II colorectal cancer patients. Expression levels of several genes related to metabolic syndrome and associated alterations were analysed by real-time qPCR in two equivalent but independent sets of stage II colorectal cancer patients. Using logistic regression models and cross-validation analysis with all tumour samples, we developed a metabolic syndrome-related gene expression profile to predict clinical outcome in stage II colorectal cancer patients. The results showed that a gene expression profile constituted by genes previously related to metabolic syndrome was significantly associated with clinical outcome of stage II colorectal cancer patients. This metabolic profile was able to identify patients with a low risk and high risk of relapse. Its predictive value was validated using an independent set of stage II colorectal cancer patients. The identification of a set of genes related to metabolic syndrome that predict survival in intermediate-stage colorectal cancer patients allows delineation of a high-risk group that may benefit from adjuvant therapy and avoid the toxic and unnecessary chemotherapy in patients classified as low risk. Our results also confirm the linkage between metabolic disorder and colorectal cancer and suggest the potential for cancer prevention and/or treatment by targeting these genes.

Pathway analysis of genome-wide association study and transcriptome data highlights new biological pathways in colorectal cancer

Colorectal cancer (CRC) is a common malignancy that meets the definition of a complex disease. Genome-wide association study (GWAS) has identified several loci of weak predictive value in CRC, however, these do not fully explain the occurrence risk. Recently, gene set analysis has allowed enhanced interpretation of GWAS data in CRC, identifying a number of metabolic pathways as important for disease pathogenesis. Whether there are other important pathways involved in CRC, however, remains unclear. We present a systems analysis of KEGG pathways in CRC using (1) a human CRC GWAS dataset and (2) a human whole transcriptome CRC case-control expression dataset. Analysis of the GWAS dataset revealed significantly enriched KEGG pathways related to metabolism, immune system and diseases, cellular processes, environmental information processing, genetic information processing, and neurodegenerative diseases. Altered gene expression was confirmed in these pathways using the transcriptome dataset. Taken together, these findings not only confirm previous work in this area, but also highlight new biological pathways whose deregulation is critical for CRC. These results contribute to our understanding of disease-causing mechanisms and will prove useful for future genetic and functional studies in CRC.