Impact of Tumor Location and Variables Associated With Overall Survival in Patients With Colorectal Cancer: A Mayo Clinic Colon and Rectal Cancer Registry Study

Demographic and clinical characteristics associated with advanced stage colorectal cancer: a registry-based cohort study in Saudi Arabia

BACKGROUND

In Saudi Arabia, approximately one-third of colorectal cancer (CRC) patients are diagnosed at an advanced stage. Late diagnosis is often associated with a worse prognosis. Understanding the risk factors for late-stage presentation of CRC is crucial for developing targeted interventions enabling earlier detection and improved patient outcomes.

METHODS

We conducted a retrospective cohort study on 17,541 CRC patients from the Saudi Cancer Registry (1997-2017). We defined distant CRCs as late-stage and localized and regional CRCs as early-stage. To assess risk factors for late-stage CRC, we first used multivariable logistic regression, then developed a decision tree to segment regions by late-stage CRC risk, and finally used stratified logistic regression models to examine geographical and sex variations in risk factors.

RESULTS

Of all cases, 29% had a late-stage diagnosis, and 71% had early-stage CRC. Young (< 50 years) and unmarried women had an increased risk of late-stage CRC, overall and in some regions. Regional risk variations by sex were observed. Sex-related differences in late-stage rectosigmoid cancer risk were observed in specific regions but not in the overall population. Patients diagnosed after 2001 had increased risks of late-stage presentation.

CONCLUSION

Our study identified risk factors for late-stage CRC that can guide targeted early detection efforts. Further research is warranted to fully understand these relationships and develop and evaluate effective prevention strategies.

Exploring the impact of stage and tumor site on colorectal cancer survival: Bayesian survival modeling

Colorectal cancer is a prevalent malignancy with global significance. This retrospective study aimed to investigate the influence of stage and tumor site on survival outcomes in 284 colorectal cancer patients diagnosed between 2001 and 2017. Patients were categorized into four groups based on tumor site (colon and rectum) and disease stage (early stage and advanced stage). Demographic characteristics, treatment modalities, and survival outcomes were recorded. Bayesian survival modeling was performed using semi-competing risks illness-death models with an accelerated failure time (AFT) approach, utilizing R 4.1 software. Results demonstrated significantly higher time ratios for disease recurrence (TR = 1.712, 95% CI 1.489-2.197), mortality without recurrence (TR = 1.933, 1.480-2.510), and mortality after recurrence (TR = 1.847, 1.147-2.178) in early-stage colon cancer compared to early-stage rectal cancer. Furthermore, patients with advanced-stage rectal cancer exhibited shorter survival times for disease recurrence than patients with early-stage colon cancer. The interaction effect between the disease site and cancer stage was not significant. These findings, derived from the optimal Bayesian log-normal model for terminal and non-terminal events, highlight the importance of early detection and effective management strategies for colon cancer. Early-stage colon cancer demonstrated improved survival rates for disease recurrence, mortality without recurrence, and mortality after recurrence compared to other stages. Early intervention and comprehensive care are crucial to enhance prognosis and minimize adverse events in colon cancer patients.

Assessment of postoperative circulating tumour DNA to predict early recurrence in patients with stage I-III right-sided colon cancer: prospective observational study

BACKGROUND

Right-sided colon cancer (RCC) differs in mutation profile and risk of recurrence compared to distal colon cancer. Circulating tumour DNA (ctDNA) present after surgery can identify patients with residual disease after curative surgery and predict risk of early recurrence.

METHODS

This is a prospective observational biomarker trial with exploration of ctDNA in 50 non-metastatic RCC patients for which oncological right-sided colectomy was performed. Blood samples were collected preoperatively, within 1 month post surgery, 3 months (not mandatory), 6 months and every 6 months thereafter. Plasma cell free DNA and/or tumour was investigated for cancer-related mutations by the next-generation sequencing (NGS) panel AVENIO surveillance specifically designed for ctDNA analysis. Detected mutations were quantified using digital droplet PCR (ddPCR) for follow-up. Recurrence-free survival was explored.

RESULTS

50 patients were recruited. Somatic cancer-related mutations were detected in 47/50 patients. ddPCR validated results from NGS for 27/34 (plasma) and 72/72 samples (tumour). Preoperative ctDNA was detected in 31/47 of the stage I/III patients and the majority of ctDNA positive patients showed reduction of ctDNA after surgery (27/31). ctDNA-positive patients at first postoperative sample had high recurrence risk compared to patients without measurable ctDNA (adjusted hazard ratio: 172.91; 95% c.i.: 8.70 to 3437.24; P: 0.001).

CONCLUSION

ctDNA was detectable in most patients with non-metastatic RCC before surgery. Positive postoperative ctDNA was strongly associated with early recurrence. Detectable postoperative ctDNA is a prognostic factor with high (100%) positive predictive value for recurrence in this cohort of non-metastatic RCC.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03776591.

Multi-omic analysis reveals metabolic pathways that characterize right-sided colon cancer liver metastasis

There are well demonstrated differences in tumor cell metabolism between right sided (RCC) and left sided (LCC) colon cancer, which could underlie the robust differences observed in their clinical behavior, particularly in metastatic disease. As such, we utilized liquid chromatography-mass spectrometry to perform an untargeted metabolomics analysis comparing frozen liver metastasis (LM) biobank samples derived from patients with RCC (N = 32) and LCC (N = 58) to further elucidate the unique biology of each. We also performed an untargeted RNA-seq and subsequent network analysis on samples derived from an overlapping subset of patients (RCC: N = 10; LCC: N = 18). Our biobank redemonstrates the inferior survival of patients with RCC-derived LM (P = 0.04), a well-established finding. Our metabolomic results demonstrate increased reactive oxygen species associated metabolites and bile acids in RCC. Conversely, carnitines, indicators of fatty acid oxidation, are relatively increased in LCC. The transcriptomic analysis implicates increased MEK-ERK, PI3K-AKT and Transcription Growth Factor Beta signaling in RCC LM. Our multi-omic analysis reveals several key differences in cellular physiology which taken together may be relevant to clinical differences in tumor behavior between RCC and LCC liver metastasis.

Integration of single-cell RNA sequencing and bulk RNA transcriptome sequencing reveals a heterogeneous immune landscape and pivotal cell subpopulations associated with colorectal cancer prognosis

Introduction

Colorectal cancer (CRC) is a highly heterogeneous cancer. The molecular and cellular characteristics differ between the colon and rectal cancer type due to the differences in their anatomical location and pathological properties. With the advent of single-cell sequencing, it has become possible to analyze inter- and intra-tumoral tissue heterogeneities.

Methods

A comprehensive CRC immune atlas, comprising 62,398 immune cells, was re-structured into 33 immune cell clusters at the single-cell level. Further, the immune cell lineage heterogeneity of colon, rectal, and paracancerous tissues was explored. Simultaneously, we characterized the TAM phenotypes and analyzed the transcriptomic factor regulatory network of each macrophage subset using SCENIC. In addition, monocle2 was used to elucidate the B cell developmental trajectory. The crosstalk between immune cells was explored using CellChat and the patterns of incoming and outgoing signals within the overall immune cell population were identified. Afterwards, the bulk RNA-sequencing data from The Cancer Genome Atlas (TCGA) were combined and the relative infiltration abundance of the identified subpopulations was analyzed using CIBERSORT. Moreover, cell composition patterns could be classified into five tumor microenvironment (TME) subtypes by employing a consistent non-negative matrix algorithm. Finally, the co-expression and interaction between SPP1+TAMs and Treg cells in the tumor microenvironment were analyzed by multiplex immunohistochemistry.

Results

In the T cell lineage, we found that CXCL13+T cells were more widely distributed in colorectal cancer tissues, and the proportion of infiltration was increased. In addition, Th17 was found accounted for the highest proportion in CD39+CD101+PD1+T cells. Mover, Ma1-SPP1 showed the characteristics of M2 phenotypes and displayed an increased proportion in tumor tissues, which may promote angiogenesis. Plasma cells (PCs) displayed a significantly heterogeneous distribution in tumor as well as normal tissues. Specifically, the IgA+ PC population could be shown to be decreased in colorectal tumor tissues whereas the IgG+ PC one was enriched. In addition, information flow mediated by SPP1 and CD44, regulate signaling pathways of tumor progression. Among the five TME subtypes, the TME-1 subtype displayed a markedly reduced proportion of T-cell infiltration with the highest proportion of macrophages which was correlated to the worst prognosis. Finally, the co-expression and interaction between SPP1+TAMs and Treg cells were observed in the CD44 enriched region.

Discussion

The heterogeneity distribution and phenotype of immune cells were analyzed in colon cancer and rectal cancer at the single-cell level. Further, the prognostic role of major tumor-infiltrating lymphocytes and TME subtypes in CRC was evaluated by integrating bulk RNA. These findings provide novel insight into the immunotherapy of CRC.

Complications after open and laparoscopic right-sided colectomy with central lymphadenectomy for colon cancer: randomized controlled trial

BACKGROUND

A central lymphadenectomy in right-sided colon cancer involves dissection along the superior mesenteric axis, but the extent is debated due to a lack of consensus and the fear of major complications. This randomized controlled trial compared the rate of postoperative morbidity in patients undergoing laparoscopic versus open right-sided colectomy with central lymphadenectomy.

METHODS

This open, prospective, randomized controlled trial compared patients operated on with open and laparoscopic right-sided colectomy (cStages I-III) with a central lymphadenectomy at two Norwegian institutions between October 2016 and December 2021. Dissections were conducted along the superior mesenteric vein in the laparoscopic group, and along the left anterior border of the superior mesenteric artery in the open group, both according to complete mesocolic excision principles. Surgery was standardized and performed by three experienced surgeons for each study group. The primary outcome of interest was to measure postoperative 30-day complications (Clavien-Dindo ≥ grade II).

RESULTS

Of 273 eligible patients, 135 were randomized and 128 analysed (63 operated on with open and 65 using laparoscopic procedures). Postoperative complications occurred in 42.8 per cent of the patients treated with open and 38.4 per cent of the patients treated using laparoscopic surgery, P = 0.372. The incidence of Clavien-Dindo grade IIIb complications was 7.9 per cent in the open versus 4.6 per cent in the laparoscopic group, P = 0.341. There were no grade IV or V complications, and no re-operations due to anastomotic leakages. There was no significant difference in the mean(s.e.m.) number of removed lymph nodes (open versus laparoscopic respectively: 31.9(1.8) versus 29.3(1.3); P = 0.235).

CONCLUSION

There was no significant difference in complications between the two groups. Standardized oncologic right-sided colectomy with central lymphadenectomy along the mesenterial root was performed safely, both open and laparoscopic, with incidence of major complications ranging between 4.6 and 7.9 per cent and no re-operations for anastomotic leakage. Radicality in terms of lymphadenectomy was comparable between the two groups.Registration number: NCT03776591 (http://www.clinicaltrials.gov).

Right colon cancer: The influence of specific location on recurrence and survival

AIM

This study aimed to investigate whether the site of the tumour within the right colon affects survival in patients who underwent right colectomy for colon cancer.

METHODS

An observational retrospective longitudinal study was performed in patients who underwent right colectomy for non-metastatic, invasive right-sided colon cancer. Patients were categorized into two groups based on tumour location: (i) caecum and ascending colon; (ii) hepatic flexure and proximal transverse colon. Demographic and clinical features were characterized, and a survival analysis was performed.

RESULTS

Of the 198 patients enroled in the study, 134 (67.8%) had caecal or ascending colon cancer and 64 (32.3%) had hepatic flexure or transverse colon cancer. Seventy (35.4%) were female and the mean age at the time of surgery was 71.6 (SD 11.4). The groups were comparable with respect to the number of lymph nodes sampled, the pTNM stage, the histological differentiation grade and the likelihood of patients receiving adjuvant chemotherapy. Recurrence rate was nearly twice as high in the hepatic flexure and proximal transverse colon group (12.5% vs 6.7%), but this difference was not statistically significant (p = 0.174). Kaplan-Meier analysis showed no differences in disease-free (p = 0.255) and overall survival (p = 0.258) between the groups.

CONCLUSION

In our population, specific location of right-sided colon cancers does not appear to have an influence on survival. Further investigation is needed to determine if tumour subsite has an impact on the recurrence rate, and whether it should be considered in defining prognosis and treatment.

Partially linear Bayesian modeling of longitudinal rank and time-to-event data using accelerated failure time model with application to brain tumor data

Joint modeling of longitudinal rank and time-to-event data with random effects model using a Bayesian approach is presented. Accelerated failure time (AFT) models can be used for the analysis of time-to-event data to estimate the effects of covariates on acceleration/deceleration of the survival time. The parametric AFT models require determining the event time distribution. So, we suppose that the time variable is modeled with Weibull AFT distribution. In many real-life applications, it is difficult to determine the appropriate distribution. To avoid this restriction, several semiparametric AFT models were proposed, containing spline-based model. So, we propose a flexible extension of the accelerated failure time model. Furthermore, the usual joint linear model, a joint partially linear model, is also considered containing the nonlinear effect of time on the longitudinal rank responses and nonlinear and time-dependent effects of covariates on the hazard. Also, a Bayesian approach that yields Bayesian estimates of the model's parameters is used. Some simulation studies are conducted to estimate parameters of the considered models. The model is applied to a real brain tumor patient's data set that underwent surgery. The results of analyzing data are presented to represent the method.

Presurgery Adhesion Molecules and Angiogenesis Biomarkers Are Differently Associated with Outcomes in Colon and Rectal Cancer: Results from the ColoCare Study

BACKGROUND

Cell-to-cell adhesion and angiogenesis are hallmarks of cancer. No studies have examined associations of adhesion molecules and angiogenesis biomarkers with clinical outcomes in colorectal cancer.

METHODS

In presurgery serum from n = 426 patients with colorectal cancer (stage I-III), we investigated associations of CRP, SAA, adhesion molecules (sICAM-1, sVCAM-1), and angiogenesis markers (VEGF-A and VEGF-D) with overall survival (OS), disease-free survival (DFS), and risk of recurrence. We computed HRs and 95% confidence intervals; adjusted for age, sex, BMI, stage, site, and study site, stratified by tumor site in exploratory analyses.

RESULTS

N = 65 (15%) were deceased, and 39 patients (14%) had a recurrence after a median follow-up of 31 months. We observed significant associations of biomarkers with OS, DFS, and risk of recurrence on a continuous scale and comparing top to bottom tertile, with HRs ranging between 1.19 and 13.92. CRP was associated with risk of death and recurrence in patients in the top tertile compared with patients in the bottom tertile, for example, risk of recurrence HRQ3-Q1: 13.92 (1.72-112.56). Significant heterogeneity between biomarkers and clinical outcomes was observed in stratified analysis by tumor site for CRP, SAA, sICAM-1, sVCAM-1, and VEGF-D. VEGF-D was associated with a 3-fold increase in risk of death for rectal cancer (HRlog2: 3.26; 95% CI, 1.58-6.70) compared with no association for colon cancer (HRlog2: 0.78; 95% CI, 0.35-1.73; Pheterogenity = 0.01).

CONCLUSIONS

Adhesion molecules and angiogenesis biomarkers are independent prognostic markers for colorectal cancer, with differences by tumor site.

IMPACT

There is need for tailored treatment for colon and rectal cancer.

Epidemiology and survival outcomes in adenosquamous carcinoma: a population-based study

BACKGROUND

The relationship between the location of the primary tumor and survival of adenosquamous carcinoma (ASC) remains poorly understood. This study aimed to evaluate the impact of primary tumor location on the survival outcome of patients with ASC.

METHODS

Patients with ASC were extracted from the Surveillance, Epidemiology, and End Results (SEER) database with ≥ 150 cases per tumor location. The Kaplan-Meier method was used to generate survival curves and differences among them were compared using the log-rank test. On the other hand, Cox proportional hazards models were used to evaluate factors that had independent predictive effects on cancer-specific survival (CSS).

RESULTS

A total of 14,829 eligible patients with ASC were included in this study. Lung and bronchus ASC accounted for 51.1%, followed by the cervix uteri (17.0%), corpus uteri (13.9%), pancreas (4.9%), esophagus (3.1%), gallbladder (2.5%), stomach (2.2%), colon and rectum (2.0%), head and neck (1.8%), and breast ASC (1.3%). The 5-year CSS of breast, cervix uteri, colon and rectum, corpus uteri, esophagus, gallbladder, head and neck, lung and bronchus, pancreas, and stomach ASC was 76.9%, 66.0%, 34.8%, 72.9%, 12.0%, 10.8%, 45.0%, 24.7%, 4.3%, and 17.3%, respectively. COX analysis demonstrated that the primary tumor location was an independent prognostic factor for CSS. Besides, the breast, uterine corpus, and cervix as well as head and neck ASC were significantly associated with better prognosis, while pancreas and gallbladder ASC were significantly associated with poor CSS; stomach and colorectal were roughly the same as ASC prognosis.

CONCLUSION

Our study showed that the CSS of patients with ASC depends on the location of the primary tumor. Besides, tumor location is an important factor that should guide the use of chemotherapy and radiation.

Mid-transverse Location in Primary Colon Tumor: A Poor Prognostic Factor?

BACKGROUND

The location of colonic tumors has been linked to different clinical and oncologic outcomes. Transverse colon cancers are generally included as right colon cancers. Furthermore, hepatic and splenic flexure tumors are usually included as components of the transverse colon.

OBJECTIVE

This study was aimed at comparing the clinicopathologic characteristics and long-term outcomes between mid-transverse and right and left colon cancers and determining the prognostic impact of the primary tumor location in the mid-transverse colon.

DESIGN

This was a retrospective study.

SETTINGS

Two specialized colorectal centers were included.

PATIENTS

Patients who underwent curative surgery for colon cancer were analyzed. Tumors located in the transverse colon, excluding the flexures, were defined as mid-transverse colon cancers.

MAIN OUTCOME MEASURES

Demographic characteristics, operative outcomes, pathologic results, and long-term outcomes were the primary outcome measures.

RESULTS

Of the 487 patients, 41 (8.4%) had mid-transverse, 191 (39.2%) had right, and 255 (52.4%) had left colon cancers. For mid-transverse colon cancers, the mean length of hospital stay, mean length of the resected specimen, and the mean number of harvested lymph nodes were significantly higher. For patients with stage I to III cancer, the 5-year overall and disease-free survival rates were significantly worse in the mid-transverse colon cancers than in the right and left colon cancers (overall survival: 55.5% vs 82.8% vs 85.9%, p = 0.004, and disease-free survival; 47.7% vs 72.4% vs 79.5%, p = 0.003). After adjustment for other clinicopathologic factors, mid-transverse colon cancers were significantly associated with a poor prognosis (HR = 2.19 [95% CI, 1.25-3.83]; p = 0.006).

LIMITATIONS

Molecular and genetic information were unavailable in this retrospective study.

CONCLUSIONS

In our case series, colon cancers located in the mid-transverse colon showed poorer prognosis than cancers in other locations. The impact of tumor location in the mid-transverse colon on prognosis, including molecular and genetic markers, should be investigated further in prospective studies. See Video Abstract at http://links.lww.com/DCR/B631.

LOCALIZACIN TRANSVERSA MEDIA EN EL TUMOR DE COLON PRIMARIO UN FACTOR DE MAL PRONSTICO

ANTECEDENTES:La ubicación de los tumores de colon se ha relacionado con diferentes resultados clínicos y oncológicos. Los cánceres de colon transverso se incluyen generalmente como cánceres de colon derecho. Además, los tumores del ángulo hepático y esplénico suelen incluirse como un componente del colon transverso.OBJETIVO:Este estudio tuvo como objetivo comparar las características clínico-patológicas y los resultados a largo plazo entre los cánceres de colon transverso medio y derecho e izquierdo y determinar el impacto pronóstico de la ubicación del tumor primario en el colon transverso medio.DISEÑO:Este fue un estudio retrospectivo.AJUSTE ENTORNO CLINICO:Se incluyeron dos centros colorrectales especializados.PACIENTES:Se analizaron los pacientes que fueron sometidos a cirugía curativa por cáncer de colon. Los tumores ubicados en el colon transverso, excluidos los ángulos, se definieron como "cánceres de colon transverso medio".PRINCIPALES MEDIDAS DE RESULTADO VOLARACION:Las características demográficas, los resultados quirúrgicos, los resultados patológicos y los resultados a largo plazo fueron las principales medidas de resultado valoracion.RESULTADOS:De los 487 pacientes, 41 (8,4%) tenían cáncer de colon transverso medio, 191 (39,2%) derecho y 255 (52,4%) cáncer de colon izquierdo. Para los cánceres de colon transverso medio, la duración media de la estancia hospitalaria, la duración de la muestra resecada y el número medio de ganglios linfáticos extraídos fueron significativamente mayores. Para los pacientes en estadio I-III, las tasas de supervivencia general y sin enfermedad a 5 años fueron significativamente peores en los cánceres de colon transverso medio que en los cánceres de colon derecho e izquierdo (supervivencia general: 55,5% frente versus a 82,8% frente versus a 85,9%, p = 0,004 y supervivencia libre de enfermedad; 47,7% frente a 72,4% frente a 79,5%, p = 0,003, respectivamente). Después del ajuste por otros factores clínico-patológicos, los cánceres de colon transverso medio se asociaron significativamente con un pronóstico desfavorable (Razón de riesgo: 2,19; intervalo de confianza del 95%: 1,25-3,83; p = 0,006).LIMITACIONES:La información molecular y genética no estuvo disponible en este estudio retrospectivo.CONCLUSIONES:En nuestra serie de casos, los cánceres de colon localizados en el colon transverso medio mostraron un peor pronóstico que los cánceres en otras localizaciones. El impacto de la ubicación del tumor en el colon transverso medio sobre el pronóstico, incluidos los marcadores moleculares y genéticos, debe investigarse más a fondo en estudios prospectivos. Consulte Video Resumen en http://links.lww.com/DCR/B631. (Traducción-Dr Adrián Ortega).

Tightly Integrated Multiomics-based Deep Tensor Survival Model for Time-to-Event Prediction

MOTIVATION

Multiomics cancer profiles provide essential signals for predicting cancer survival. It is challenging to reveal the complex patterns from multiple types of data and link them to survival outcomes. We aim to develop a new deep learning-based algorithm to integrate three types of high-dimensional omics data measured on the same individuals to improve cancer survival outcome prediction.

RESULTS

We built a three-dimension tensor to integrate multi-omics cancer data and factorized it into two-dimension matrices of latent factors, which were fed into neural networks-based survival networks. The new algorithm and other multi-omics-based algorithms, as well as individual genomic-based survival analysis algorithms, were applied to the breast cancer data colon and rectal cancer data from The Cancer Genome Atlas (TCGA) program. We evaluated the goodness-of-fit using the concordance index (C-index) and Integrated Brier Score (IBS). We demonstrated that the proposed tight integration framework has better survival prediction performance than the models using individual genomic data and other conventional data integration methods.

AVAILABILITY

https://github.com/jasperzyzhang/DeepTensorSurvival.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Development and external validation of a novel nomogram for predicting cancer-specific survival in patients with ascending colon adenocarcinoma after surgery: a population-based study

Background

This study aimed to develop and validate a novel nomogram to predict the cancer-specific survival (CSS) of patients with ascending colon adenocarcinoma after surgery.

Methods

Patients with ascending colon adenocarcinoma were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database from 1973 to 2015 and randomly divided into a training set (5930) and a validation set (2540). The cut-off values for age, tumour size and lymph node ratio (LNR) were calculated via X-tile software. In the training set, independent prognostic factors were identified using univariate and multivariate Cox analyses, and a nomogram incorporating these factors was subsequently built. Data from the validation set were used to assess the reliability and accuracy of the nomogram and then compared with the 8th edition of the American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) staging system. Furthermore, external validation was performed from a single institution in China.

Results

A total of 8470 patients were enrolled from the SEER database, 5930 patients were allocated to the training set, 2540 were allocated to the internal validation set and a separate set of 473 patients was allocated to the external validation set. The optimal cut-off values of age, tumour size and lymph node ratio were 73 and 85, 33 and 75 and 4.9 and 32.8, respectively. Univariate and multivariate Cox multivariate regression revealed that age, AJCC 8th edition T, N and M stage, carcinoembryonic antigen (CEA), tumour differentiation, chemotherapy, perineural invasion and LNR were independent risk factors for patient CSS. The nomogram showed good predictive ability, as indicated by discriminative ability and calibration, with C statistics of 0.835 (95% CI, 0.823–0.847) and 0.848 (95% CI, 0.830–0.866) in the training and validation sets and 0.732 (95% CI, 0.664–0.799) in the external validation set. The nomogram showed favourable discrimination and calibration abilities and performed better than the AJCC TNM staging system.

Conclusions

A novel validated nomogram could effectively predict patients with ascending colon adenocarcinoma after surgery, and this predictive power may guide clinicians in accurate prognostic judgement.

Survival Trends of Right- and Left-Sided Colon Cancer across Four Decades: A Norwegian Population-Based Study

BACKGROUND

Patients with right-sided colon cancer (RCC) and left-sided colon cancer (LCC) differ clinically and molecularly. The main objective was to investigate stage-stratified survival and recurrence of RCC and LCC across four 10-year periods.

METHODS

Patients diagnosed from 1977 to 2016 with colon adenocarcinoma were included from the Cancer Registry of Norway. Primary tumor location (PTL) was defined as RCC if proximal and LCC if distal to the splenic flexure. Multivariable regressions were used to estimate HRs for overall survival (OS), recurrence-free survival (RFS), survival after recurrence (SAR), and excess HRs (eHR) for relative survival (RS).

RESULTS

72,224 patients were eligible for analyses [55.1% (n = 39,769/72,224) had RCC]. In 1977 to 1986, there was no difference between LCC and RCC in OS [HR, 1.01; 95% confidence interval (CI), 0.97-1.06; P = 0.581] or RS (eHR, 0.96; 95% CI, 0.90-1.02; P = 0.179). In 2007 to 2016, LCC had significantly better OS (HR, 0.84; 95% CI, 0.80-0.87; P < 0.001) and RS (eHR, 0.76; 95% CI, 0.72-0.81; P < 0.001) compared with RCC. The gradually diverging and significantly favorable prognosis for LCC was evident for distant disease across all time periods and for regional disease from 2007 onward. There was no difference in RFS between LCC and RCC in patients less than 75 years during 2007 to 2016 (HR, 0.99; 95% CI, 0.91-1.08; P = 0.819); however, SAR was significantly better for LCC (HR, 0.61; 95% CI, 0.53-0.71; P < 0.001).

CONCLUSIONS

A gradually diverging and increasingly favorable prognosis was observed for patients with LCC with advanced disease over the past four decades.

IMPACT

Current PTL survival disparities stress the need for further exploring targetable molecular subgroups across and within different PTLs to further improve patient outcomes.

The impact of tumor location on long-term survival outcomes in patients with right-sided colon cancer

BACKGROUND

The oncologic outcomes of right-sided cancers are generally grouped in studies. We hypothesized that tumor location (cecal vs. ascending vs. hepatic flexure) may influence cancer-specific outcomes.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for patients over 18 with non-metastatic, invasive (American Joint Committee on Cancer stage I-III) right-sided adenocarcinoma of the colon from 1988 to 2014 who underwent partial colectomy. Patients were categorized into groups: (1) cecum (2) ascending colon (3) hepatic flexure. Demographic, clinical and pathologic factors were compared between groups. Disease-specific and overall survival were described using the Kaplan-Meier method and compared using the log-rank test. Multivariate Cox regression analysis determined the independent association of primary tumor location.

RESULTS

We identified 167,450 patients. Mean age was 72.2 ± 12.3 years and 54.9% were female. Of these, 81,611, 66,857, and 18,982 had cecal, ascending colon, and hepatic flexure cancers, respectively. Cecal cancers were associated with a lower number of examined nodes but a higher likelihood of nodal positivity. Cecal cancer patients were significantly older, had larger tumors, and higher tumor stage. On univariate analysis, cecal cancers were associated with poorer disease-specific and overall survival (all p values < 0.001). On multivariate analysis controlling for sex, age, tumor size, number of examined nodes and stage, hepatic flexure cancers were associated with worse disease-specific (HR 1.05) and overall survival (HR 1.03).

CONCLUSION

Hepatic flexure cancers are associated with worse survival compared to more proximal colon cancers. The cause is likely multifactorial, including biological and technical factors. More aggressive surgical and multimodal therapy may be considered for hepatic flexure colon cancers.

Tumor Size >5 cm and Harvested LNs <12 Are the Risk Factors for Recurrence in Stage I Colon and Rectal Cancer after Radical Resection

Simple Summary

We analyzed the data from 1952 patients with stage I colorectal cancer to evaluate the risk factors for recurrence and survival rates. In the entire cohort, the recurrence rate was 4.6%. There were some differences in the risk factors for recurrence between colon and rectal cancer in stage I colorectal cancer. Left-sided tumors, T2, tumor size >5 cm, and lymphovascular invasion were independent risk factors of colon cancer recurrence. Male, preoperative carcinoembryonic antigen (CEA) ≥2.5 ng/mL, and harvested lymph nodes (LNs) <12 were independently associated with recurrence of rectal cancer. Even though patients with early-stage CRC underwent curative resection, survival sharply decreased in cases of recurrence. Our findings could suggest more aggressive surveillance for patients with an increased risk of recurrence.

Abstract

Recurrence can still occur even after radical resection of stage I colorectal cancer (CRC). This study aimed to identify subgroups with a high risk for recurrence in the stage I CRC. We retrospectively reviewed prospectively collected data of 1952 patients with stage I CRC after radical resection between 2002 and 2017 at our institute. 1398 (colon, 903 (64.6%), rectum, 495 (35.4%)) were eligible for analysis. We analyzed the risk factors for recurrence and survival. During the follow-up period (median: 59 months), 63 (4.6%) had a recurrence. The recurrence rate of rectal cancer was significantly higher than that of colon cancer (8.5% vs. 2.3%). Left-sided tumors, T2, tumor size >5 cm, and lymphovascular invasion were independent risk factors of colon cancer recurrence. Male, preoperative carcinoembryonic antigen (CEA) ≥2.5 ng/mL, and harvested lymph nodes (LNs) <12 were independently associated with recurrence of rectal cancer. Recurrence affected OS (5-year OS: 97.1% vs. 67.6%). Despite curative resection, survival sharply decreased with recurrence. The risk factors for recurrence were different between colon and rectal cancer. Patients with a higher risk for recurrence should be candidates for more aggressive surveillance, even in early-stage CRC.

Impact of SARS-CoV-2 Pandemic on Colorectal Cancer Screening Delay: Effect on Stage Shift and Increased Mortality

BACKGROUND & AIMS

The SARS-CoV-2 pandemic had a sudden, dramatic impact on healthcare. In Italy, since the beginning of the pandemic, colorectal cancer (CRC) screening programs have been forcefully suspended. We aimed to evaluate whether screening procedure delays can affect the outcomes of CRC screening.

METHODS

We built a procedural model considering delays in the time to colonoscopy and estimating the effect on mortality due to up-stage migration of patients. The number of expected CRC cases was computed by using the data of the Italian screened population. Estimates of the effects of delay to colonoscopy on CRC stage, and of stage on mortality were assessed by a meta-analytic approach.

RESULTS

With a delay of 0-3 months, 74% of CRC is expected to be stage I-II, while with a delay of 4-6 months there would be a 2%-increase for stage I-II and a concomitant decrease for stage III-IV (P = .068). Compared to baseline (0-3 months), moderate (7-12 months) and long (> 12 months) delays would lead to a significant increase in advanced CRC (from 26% to 29% and 33%, respectively; P = .008 and P < .001, respectively). We estimated a significant increase in the total number of deaths (+12.0%) when moving from a 0-3-months to a >12-month delay (P = .005), and a significant change in mortality distribution by stage when comparing the baseline with the >12-months (P < .001).

CONCLUSIONS

Screening delays beyond 4-6 months would significantly increase advanced CRC cases, and also mortality if lasting beyond 12 months. Our data highlight the need to reorganize efforts against high-impact diseases such as CRC, considering possible future waves of SARS-CoV-2 or other pandemics.

The value of circulating fibrinogen-to-pre-albumin ratio in predicting survival and benefit from chemotherapy in colorectal cancer

Background:

To evaluate the prognostic role of circulating fibrinogen-to-pre-albumin (FPR) in colorectal cancer (CRC) with different tumor locations, and its involvement in chemosensitivity and chemoresistance.

Patients and methods:

A total of 2917 eligible CRC patients from multiple centers were enrolled in this prospective study, and 3 years follow-up was carried out to obtain the outcome of these patients. Circulating fibrinogen (Fib), pre-albumin (pAlb), carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9) were detected, and we calculated FPR according to the detected results. Kaplan–Meier curves, Cox proportional regression, time-dependent receiver operating characteristic curves, Harrell’s concordance index, calibration, and decision curves were used to investigate the role of FPR in predicting chemotherapy efficacy and prognosis of CRC patients.

Results:

Our results showed that cancer bulk, its infiltrating depth, and the distal metastasis status of CRC determined circulating FPR levels. A high FPR was associated with a significantly inferior prognosis, while the outcomes of right-sided patients with stage III and IV CRC were worse than left-sided cases. Only FPR was found to be a reliable and independent prognostic factor for each stage of CRC. In addition, the prognostic FPR-contained nomograms were superior to the non-FPR nomograms and FPR in predicting the outcomes in both localized and metastatic CRC patients. The circulating FPR was significantly associated with chemotherapeutic efficacy in stage III and IV CRC patients. In particular, low-grade (FPR < 15) and medium-grade (15 ⩽ FPR < 20) FPR patients exhibited a complete response to chemotherapy and attenuated chemosensitivity, respectively; in contrast, high-grade inflammation (FPR ⩾ 20) conferred resistance to the treatment.

Conclusion:

Circulating FPR is a robust and independent prognostic factor, a simple and economically-friendly predictor of chemotherapy efficacy within cases of localized and metastatic CRC. FPR-contained nomograms are more effective in predicting the prognosis of these patients. FPR and the nomogram can be recommended for the evaluation of chemotherapy efficacy and to aid decision-making associated with the management of these patients.

New Anastomosis Technique to Prevent Anastomotic Leakage in Laparoscopic Anterior Resection for Rectal Cancer, Especially Upper Rectal Cancer

BACKGROUND/AIM

Anastomotic leakage (AL) is a major problem in rectal cancer surgery. To prevent AL, we developed a side-to-side anastomosis technique using a circular stapler and termed it the circular side stapling technique (CST). We herein report the method and outcome of the CST.

PATIENTS AND METHODS

In this study, we analyzed 154 patients with stage 0 to III rectal cancer who underwent curative laparoscopic low anterior resection. Perioperative factors and complications were compared between the CST and usual double stapling technique (DST).

RESULTS

The CST was performed in 110 of the 154 patients. When comparing the outcomes of patients with upper rectal cancer. AL occurred in no patients in the CST group and in three patients in the DST group (p=0.011). The CST prevented AL in all patients with upper rectal cancer.

CONCLUSION

The CST is a safe and useful procedure in laparoscopic anterior resection. This technique can prevent AL, especially in patients with upper rectal cancer.

Colon cancer survival differs from right side to left side and lymph node harvest number matter

Background

Right-sided colorectal cancer (CRC) has worse survival than does left-sided CRC. The objective of this study was to further assess the impact of right-side location on survival and the role of the extent of lymphadenectomy.

Methods

All CRCs diagnosed between 2000 and 2012 in Emilia-Romagna Region, Italy, were included. Data for stage, grade, histology, screening history, and number of removed lymph nodes (LN) were collected. Multivariable Cox regression models were used to estimate hazard ratios (HR), with relative 95% confidence intervals (95%CI), of right vs. left colon and of removing < 12, 12–21 or > 21 lymph nodes by cancer site.

Results

During the study period, 29,358 patients were registered (8828 right colon, 18,852 left colon, 1678 transverse). Patients with right cancer were more often older, females, with advanced stage and high grade, and higher number of removed LNs. Five-year survival was lower in the right than in the left colon (55.2% vs 59.7%). In multivariable analysis, right colon showed a lower survival when adjusting for age, sex, and screening status (HR 1.12, 95%CI 1.04–1.21). Stratification by number of lymph nodes removed (12–21 or > 21) was associated with better survival in right colon (HR 0.54, 95%CI 0.40–0.72 and HR 0.40, 95%CI 0.30–0.55, respectively) compared to left colon (HR 0.89, 95%CI 0.76–1.06 and HR 0.83, 95%CI 0.69–1.01, respectively).

Conclusions

This study confirms that right CRC has worse survival; the association is not due to screening status. An adequate removal of lymph nodes is associated with better survival, although the direction of the association in terms of causal links is not clear.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10746-4.

microR-4449 Promotes Colorectal Cancer Cell Proliferation via Regulation of SOCS3 and Activation of STAT3 Signaling

Introduction

Dysregulation of microRNAs (miRNAs), which represented a critical level of gene expression modulation, regulated the development of colorectal cancer. However, the functions of numerous miRNAs remain unclear in colorectal cancer.

Methods

The microarray data of GSE115513 were retrieved; subsequently, the differentially expressed miRNAs between 411 colon tumors and 381 normal colon mucosa were analyzed. Real-time PCR (RT-qPCR) and bioinformatic analysis were applied to examine the expression of miR-4449 in collected colorectal tumors and published microarray data. The activity of signal transducer and activator of transcription 3 (STAT3) signaling was detected by Western blotting and RT-qPCR. Dual-Luciferase assay and bioinformatic analysis were used to confirm the interaction between suppressor of cytokine signaling 3 (SOCS3) and miR-4449. Loss of function and rescue assays were performed to study the involvement of miR-4449 and SOCS3 in cell proliferation and apoptosis of colorectal cancer.

Results

Herein, we identified miR-4449 as a novel upregulated miRNA in colorectal cancer. Our data suggested that miR-4449 downregulation blocked the proliferation of colorectal cancer cells accompanied with the elevation of cell apoptosis. Decreased expression of miR-4449 led to inactivation of STAT3 pathway as indicated by dephosphorylation of STAT3 and downregulation of STAT3 target genes, including vascular endothelial growth factor (VEGF), c-Myc, baculovirus inhibitor of apoptosis containing 5 (BIRC5). Furthermore, SOCS3, a negative regulator of STAT3 pathway, was found to be a target gene of miR-4449. The data also showed that the inactivation of STAT3 pathway by miR-4449 inhibitor was realized by targeting SOCS3. Moreover, the biological function of miR-4449 downregulation was reversed by SOCS3 knockdown in colorectal cancer cells.

Conclusion

The current study revealed that miR-4449 promoted cell proliferation of colorectal cancer and was a promising potential therapeutic target for colorectal cancer.

Sex- and Gender-Based Pharmacological Response to Drugs

In humans, the combination of all sex-specific genetic, epigenetic, and hormonal influences of biologic sex produces different in vivo environments for male and female cells. We dissect how these influences of sex modify the pharmacokinetics and pharmacodynamics of multiple drugs and provide examples for common drugs acting on specific organ systems. We also discuss how gender of physicians and patients may influence the therapeutic response to drugs. We aim to highlight sex as a genetic modifier of the pharmacological response to drugs, which should be considered as a necessary step toward precision medicine that will benefit men and women. SIGNIFICANCE STATEMENT: This study discusses the influences of biologic sex on the pharmacokinetics and pharmacodynamics of drugs and provides examples for common drugs acting on specific organ systems. This study also discusses how gender of physicians and patients influence the therapeutic response to drugs.

Ferroptosis-related genes are potential prognostic molecular markers for patients with colorectal cancer

Ferroptosis is a newly discovered programmed cell death that plays a vital role in the occurrence and development of tumors. However, little is known about its prognostic value of ferroptosis-related genes (FRGs) in colorectal cancer (CRC). This study was to investigate the clinical significance of FRGs on overall survival (OS) of patients with CRC. The mRNA expression profiles and corresponding clinical data of CRC patients were downloaded from public databases. Least absolute shrinkage and selection operator (LASSO) Cox regression was applied to identify hub FRGs and establish a novel ferroptosis-related gene signature in predicting OS in training cohort, and assessed in the validation cohort. Then, the genomic-clinicopathologic nomogram integrating risk scores and clinicopathological features were established. Thirteen FRGs were identified to be most significantly related to the OS of CRC patients. Based on the LASSO Cox regression algorithm, we selected 10 genes from 13 FRGs to establish a prognostic risk signature. The log-rank test and Kaplan-Meier analysis confirmed the predictive value of the risk scores for OS in CRC patients. The time-dependent receiver operating characteristic (tdROC) of signature indicates the showed powerful prediction ability in both training cohort and validation cohort. Then, a genomic-clinicopathologic nomogram integrating age, stage, and risk scores was established and demonstrated high predictive accuracy and clinical value, which was validated through tdROC and calibration curves. The ferroptosis-related gene signature and genomic-clinicopathologic nomogram could be used to predict the prognosis of CRC patients and might also be potential therapeutic targets.

Type 2 Innate Lymphoid Cells Protect against Colorectal Cancer Progression and Predict Improved Patient Survival

Chronic inflammation of the gastrointestinal (GI) tract contributes to colorectal cancer (CRC) progression. While the role of adaptive T cells in CRC is now well established, the role of innate immune cells, specifically innate lymphoid cells (ILCs), is not well understood. To define the role of ILCs in CRC we employed complementary heterotopic and chemically-induced CRC mouse models. We discovered that ILCs were abundant in CRC tumours and contributed to anti-tumour immunity. We focused on ILC2 and showed that ILC2-deficient mice developed a higher tumour burden compared with littermate wild-type controls. We generated an ILC2 gene signature and using machine learning models revealed that CRC patients with a high intratumor ILC2 gene signature had a favourable clinical prognosis. Collectively, our results highlight a critical role for ILC2 in CRC, suggesting a potential new avenue to improve clinical outcomes through ILC2-agonist based therapeutic approaches.

Analysis of first-line treatment in older patients with metastasic colorectal cancer

OBJECTIVE

The purpose of this study was to analyse the effectiveness and safety of first-line treatment of metastatic colorectal cancer (CRCm) in older patients treated in a tertiary hospital.

MATERIAL AND METHODS

This was an observational and retrospective study, including patients aged 75 years or older, with CRCm, who received chemotherapy treatment in 2017. The main variables studied were type of treatment, Progression-Free Survival (PFS), Overall Survival (OS), dose reductions, and treatment delays due to adverse events.

RESULTS

A total of 59 patients (71.2% men) with a median age of 76 years were enrolled in this study. About 70% presented colon cancer, with the left colon being the most frequent location. They were treated with 9 different schemes, in most cases using polychemotherapy and biological agents. The median PFS and OS was 12 and 30 months, respectively. A total of 23/59 of patients started treatment at doses lower than recommended in the clinical practice guidelines. In terms of safety, 34/59 of patients had at least one dose reduction, and 30/59 suffered one treatment delay. The most frequent adverse reactions were asthenia, peripheral neuropathy, diarrhoea, and palmoplantar erythrodysesthesia.

CONCLUSION

Our patients presented baseline clinical characteristics similar to the general adult population, with no tumour characteristics associated with advanced age. The efficacy and toxicity were similar to those in the clinical trials, although our patients had more dose reductions. Considering the heterogeneity of patients and in the absence of clinical trials in the older population, real-life studies can be very useful.

Colorectal Cancer in Octogenarian and Nonagenarian Patients: Clinicopathological Features and Survivals

Purpose

Elderly population will comprise a substantial proportion of colorectal cancer (CRC) patients. We examined patients older than 80 years according to their clinical and pathological characteristics to fully understand the elderly patients.

Methods

CRC patients, 60 years or older at diagnosis, admitted between 2009 and 2014 at our hospital were enrolled. The patients were divided into 2 groups: elderly (aged > 80 years, n = 133), and controls (aged 60 to 79 years, n = 596). Patient’s demographics, risk factors for prognosis of CRC, Clinicopathological parameters, treatment, and survival rates were compared.

Results

The mean ages were 83.9 and 64.8 years, respectively. Male-to-female ratio and tumor sidedness were comparable in both groups. Prognostic factors found in univariate analysis; differentiation, stage, lymphovascular invasion, and carcinoembryonic antigen showed no statistical difference. The microsatellite instability status and number of retrieved lymph nodes were also similar (17.2 vs 21.6, P = 0.505). A significant difference was found in the treatment approach for chemotherapy as the elderly patients with stage III and IV tend to have omitted adjuvant (43.6% vs. 92.8%, P < 0.001) or palliative (35.8% vs. 89.4%, P = 0.016) chemotherapy. Except in stage I, elderly patients showed significantly lower overall survival rates.

Conclusion

Current study shows far-elderly patients with CRC were less likely to receive standard treatments, which might have resulted in an inferior outcome. As the number of elderly patients with CRC increase, our results provide a basis for further clinical and molecular investigations of elderly CRC patients.

Prognostic Factors Involved in the Epithelial-Mesenchymal Transition Process in Colorectal Cancer Have a Preponderant Role in Oxidative Stress: A Systematic Review and Meta-Analysis

Epithelial-to-mesenchymal transition (EMT) is one of the most accepted mechanisms leading to metastasis, which is responsible for most of the cancer-related deaths. In order to identify EMT-related biomarkers able to predict clinical outcomes in colorectal cancer (CRC), a systematic review and meta-analysis of prognostic factors associated to overall survival (OS) and progression free survival (PFS) was conducted. The systematic literature search included studies from June 2014 to June 2019 available at PubMed and Scopus databases. Meta-analysis was performed for those markers appearing in minimum three works with a total number of 8656 participants. The rest were enlisted and subjected to functional enrichment. We identified nine clinical biomarkers and 73 EMT-related molecular biomarkers associated to OS and/or PFS in CRC. The significant enrichment of biomarkers found involved in cellular oxidoreductase activity suggests that ROS generation plays an active role in the EMT process. Clinical practice needs new biomarkers with a reliable prognostic value able to predict clinical outcomes in CRC. Our integrative work supports the role of oxidative stress in tumorigenesis and EMT progress highlighting the importance of deciphering this specific mechanism to get a better understanding of metastasis.

Simultaneous approach for patients with synchronous colon and rectal liver metastases: Impact of site of primary on postoperative and oncological outcomes

BACKGROUND AND AIMS

We aimed to investigate the impact of the site of the primary on postoperative and oncological outcomes in patients undergone simultaneous approach for colon (CC) and rectal cancer (RC) with synchronous liver metastases (SCRLM).

PATIENTS AND METHODS

Of the 220 patients with SCRLM operated on between Mar 2006 and Dec 2017, 169 patients (76.8%) were treated by a simultaneous approach and were included in the study. Two groups were considered according to the location of primary tumor RC-Group (n = 47) and CC-group (n = 122).

RESULTS

Multiple liver metastases were observed in 70.2% in RC-Group and 77.0% in CC-Group (p = 0.233), whilst median Tumor Burden Score (TBS) was 4.7 in RC-Group and 5.4 CC-Group (p = 0.276). Severe morbidity (p = 0.315) and mortality at 90 days (p = 0.520) were comparable between RC-Group and CC-Group. The 5-year overall survival (OS) rate was similar comparing RC-Group and CC-Group (48.2% vs. 45.3%; p = 0.709), but it was significantly different when considering left-CC, right-CC and RC separately (54.5% vs. 35.2% vs. 48.2%; p = 0.041). Primary tumor location (right-CC, p = 0.001; RC, p = 0.002), microscopic residual (R1) disease at the primary (p < 0.001), TBS ≥6 (p = 0.012), bilobar metastases (p = 0.004), and chemotherapy strategy (preoperative ChT, p = 0.253; postoperative ChT, p = 0.012; and perioperative ChT, p < 0.001) resulted to be independent prognostic factors at multivariable analysis.

CONCLUSION

In patients with SCRLM, simultaneous resection of the primary tumor and liver metastases seems feasible and safe and allows satisfactory oncological outcomes both in CC and RC. Right-CC shows a worse prognosis when compared to left-CC and RC.

Selected Oxidative Stress Markers in Colorectal Cancer Patients in Relation to Primary Tumor Location-A Preliminary Research

Background and objectives: Ample evidence indicates that oxidative stress, including complex lipid peroxidation processes, may play a significant role in the pathogenesis of colorectal cancer. The goal of this study was to evaluate selected oxidative stress markers in patients with colorectal cancer depending on some clinical features, with particular attention paid to the location of the primary tumor. Materials and Methods: The study was conducted on a group of 66 patients with colorectal cancer. The study consisted of two stages. The first stage involved the analysis of medical records; the second consisted of determining selected oxidative stress markers by measuring malondialdehyde as well as total oxidant and antioxidant status. Results: Of all patients, 43 (65.15%) had colon cancer, of whom 30 (69.77%) had a tumor on the left side and 13 (30.23%) had a tumor on the right side of the colon. Of all the patients, 23 (34.85%) had rectal cancer. The mean total oxidant and antioxidant status was 809.76 (SD ± 392.65) µmol/L and 253.19 (233.33-310.66) µmol/L, respectively. The mean malondialdehyde serum level was 2478.04 (SD ± 1397.05) ng/mL. The mean malondialdehyde serum concentration in patients with primary tumors located on the right side was higher in a statistically significant way compared with the remaining patients. Conclusions: It was demonstrated that the intensity of lipid peroxidation processes is correlated with the development of colorectal cancer, particularly on the right side. The results should be interpreted rather cautiously due to certain limitations of the study.

Metabolite profile comparisons between ascending and descending colon tissue in healthy adults

BACKGROUND

Obesity is a risk factor for colorectal cancer, yet metabolic distinctions between healthy right and left colon tissue, before cancer is diagnosed, remains largely unknown. This study compared right-ascending and left-descending colon tissue metabolomes to identify differences from the stool metabolome in normal weight, overweight, and obese adults.

AIM

To examine right and left colon tissue metabolites according to body mass index that may serve as mechanistic targets for interventions and biomarkers for colon cancer risk.

METHODS

Global, non-targeted metabolomics was applied to assess right-ascending and left-descending colon tissue collected from healthy adults undergoing screening colonoscopies to test the hypothesis that BMI differentially impacts colon tissue metabolite profiles. The colon tissue and stool metabolome of healthy adults (n = 24) was analyzed for metabolite signatures and metabolic pathway networks implicated in progression of colorectal cancer.

RESULTS

Ascending and descending colon contained 504 host, food, and microbiota-derived metabolites from normal weight, overweight and obese adults grouped according to body mass index. Amino acids, lipids, and nucleotides were among the chemical types that further differentiated from the stool metabolite profiles. Normal weight adults had 46 significantly different metabolites between ascending and descending colon tissue locations, whereas there were 37 metabolite differences in overweight and 28 metabolite differences for obese adults (P < 0.05). Obese adults had trimethylamine N-oxide, endocannabinoids and monoacylglycerols with different relative abundances identified between ascending and descending colon. Primary and secondary bile acids, vitamins, and fatty acids also showed marked relative abundance differences in colon tissue from overweight/obese adults.

CONCLUSION

There were metabolite profile differences between right-ascending and left-descending colon tissue in healthy adults. Colon lipids and other metabolites in obese and overweight adults were distinguished from normal weight participants and associated with gut inflammation, nutrient absorption, and products of microbiota metabolism.

Genome-Wide Identification of a Novel Autophagy-Related Signature for Colorectal Cancer

Background:

Plenty of evidence has suggested that autophagy plays a crucial role in the biological processes of cancers. This study aimed to screen autophagy-related genes (ARGs) and establish a novel a scoring system for colorectal cancer (CRC).

Methods:

Autophagy-related genes sequencing data and the corresponding clinical data of CRC in The Cancer Genome Atlas were used as training data set. The GSE39582 data set from the Gene Expression Omnibus was used as validation set. An autophagy-related signature was developed in training set using univariate Cox analysis followed by stepwise multivariate Cox analysis and assessed in the validation set. Then we analyzed the function and pathways of ARGs using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Finally, a prognostic nomogram combining the autophagy-related risk score and clinicopathological characteristics was developed according to multivariate Cox analysis.

Results:

After univariate and multivariate analysis, 3 ARGs were used to construct autophagy-related signature. The KEGG pathway analyses showed several significantly enriched oncological signatures, such as p53 signaling pathway, apoptosis, human cytomegalovirus infection, platinum drug resistance, necroptosis, and ErbB signaling pathway. Patients were divided into high- and low-risk groups, and patients with high risk had significantly shorter overall survival (OS) than low-risk patients in both training set and validation set. Furthermore, the nomogram for predicting 3- and 5-year OS was established based on autophagy-based risk score and clinicopathologic factors. The area under the curve and calibration curves indicated that the nomogram showed well accuracy of prediction.

Conclusions:

Our proposed autophagy-based signature has important prognostic value and may provide a promising tool for the development of personalized therapy.