ColoType: a forty gene signature for consensus molecular subtyping of colorectal cancer tumors using whole-genome assay or targeted RNA-sequencing

Abstract Background Clinical-grade whole-genome sequencing (cWGS) has the potential to become the standard of care within the clinic because of its breadth of coverage and lack of bias towards certain regions of the genome. Colorectal cancer presents a difficult treatment paradigm, with over 40% of patients presenting at diagnosis with metastatic disease. We hypothesised that cWGS coupled with 3′ transcriptome analysis would give new insights into colorectal cancer. Methods Patients underwent PCR-free whole-genome sequencing and alignment and variant calling using a standardised pipeline to output SNVs, indels, SVs and CNAs. Additional insights into the mutational signatures and tumour biology were gained by the use of 3′ RNA-seq. Results Fifty-four patients were studied in total. Driver analysis identified the Wnt pathway gene APC as the only consistently mutated driver in colorectal cancer. Alterations in the PI3K/mTOR pathways were seen as previously observed in CRC. Multiple private CNAs, SVs and gene fusions were unique to individual tumours. Approximately 30% of patients had a tumour mutational burden of > 10 mutations/Mb of DNA, suggesting suitability for immunotherapy. Conclusions Clinical whole-genome sequencing offers a potential avenue for the identification of private genomic variation that may confer sensitivity to targeted agents and offer patients new options for targeted therapies.

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Bacterial community structure alterations within the colorectal cancer gut microbiome

BMC Microbiology ◽

10.1186/s12866-021-02153-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mark Loftus ◽

Sayf Al-Deen Hassouneh ◽

Shibu Yooseph

Keyword(s):

Colorectal Cancer ◽

Community Structure ◽

Bacterial Community ◽

Gut Microbiome ◽

Late Stage ◽

Bacterial Community Structure ◽

Whole Genome ◽

Human Gut ◽

Fecal Samples ◽

Human Gut Microbiome

Abstract Background Colorectal cancer is a leading cause of cancer-related deaths worldwide. The human gut microbiome has become an active area of research for understanding the initiation, progression, and treatment of colorectal cancer. Despite multiple studies having found significant alterations in the carriage of specific bacteria within the gut microbiome of colorectal cancer patients, no single bacterium has been unequivocally connected to all cases. Whether alterations in species carriages are the cause or outcome of cancer formation is still unclear, but what is clear is that focus should be placed on understanding changes to the bacterial community structure within the cancer-associated gut microbiome. Results By applying a novel set of analyses on 252 previously published whole-genome shotgun sequenced fecal samples from healthy and late-stage colorectal cancer subjects, we identify taxonomic, functional, and structural changes within the cancer-associated human gut microbiome. Bacterial association networks constructed from these data exhibited widespread differences in the underlying bacterial community structure between healthy and colorectal cancer associated gut microbiomes. Within the cancer-associated ecosystem, bacterial species were found to form associations with other species that are taxonomically and functionally dissimilar to themselves, as well as form modules functionally geared towards potential changes in the tumor-associated ecosystem. Bacterial community profiling of these samples revealed a significant increase in species diversity within the cancer-associated gut microbiome, and an elevated relative abundance of species classified as originating from the oral microbiome including, but not limited to, Fusobacterium nucleatum, Peptostreptococcus stomatis, Gemella morbillorum, and Parvimonas micra. Differential abundance analyses of community functional capabilities revealed an elevation in functions linked to virulence factors and peptide degradation, and a reduction in functions involved in amino-acid biosynthesis within the colorectal cancer gut microbiome. Conclusions We utilize whole-genome shotgun sequenced fecal samples provided from a large cohort of late-stage colorectal cancer and healthy subjects to identify a number of potentially important taxonomic, functional, and structural alterations occurring within the colorectal cancer associated gut microbiome. Our analyses indicate that the cancer-associated ecosystem influences bacterial partner selection in the native microbiota, and we highlight specific oral bacteria and their associations as potentially relevant towards aiding tumor progression.

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Interleukin-11-expressing fibroblasts have a unique gene signature correlated with poor prognosis of colorectal cancer

Nature Communications ◽

10.1038/s41467-021-22450-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Takashi Nishina ◽

Yutaka Deguchi ◽

Daisuke Ohshima ◽

Wakami Takeda ◽

Masato Ohtsuka ◽

...

Keyword(s):

Colorectal Cancer ◽

Tumor Cells ◽

Human Cancer ◽

Tumor Development ◽

Gene Signature ◽

Free Survival ◽

Expression Of Genes ◽

Reporter Mice ◽

Interleukin 11

AbstractInterleukin (IL)-11 is a member of the IL-6 family of cytokines and is involved in multiple cellular responses, including tumor development. However, the origin and functions of IL-11-producing (IL-11+) cells are not fully understood. To characterize IL-11+ cells in vivo, we generate Il11 reporter mice. IL-11+ cells appear in the colon in murine tumor and acute colitis models. Il11ra1 or Il11 deletion attenuates the development of colitis-associated colorectal cancer. IL-11+ cells express fibroblast markers and genes associated with cell proliferation and tissue repair. IL-11 induces the activation of colonic fibroblasts and epithelial cells through phosphorylation of STAT3. Human cancer database analysis reveals that the expression of genes enriched in IL-11+ fibroblasts is elevated in human colorectal cancer and correlated with reduced recurrence-free survival. IL-11+ fibroblasts activate both tumor cells and fibroblasts via secretion of IL-11, thereby constituting a feed-forward loop between tumor cells and fibroblasts in the tumor microenvironment.

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Cytotoxic Escherichia coli strains encoding colibactin, cytotoxic necrotizing factor, and cytolethal distending toxin colonize laboratory common marmosets (Callithrix jacchus)

Scientific Reports ◽

10.1038/s41598-020-80000-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Colleen S. McCoy ◽

Anthony J. Mannion ◽

Yan Feng ◽

Carolyn M. Madden ◽

Stephen C. Artim ◽

...

Keyword(s):

Colorectal Cancer ◽

Cellular Differentiation ◽

Gastrointestinal Disease ◽

Phylogenetic Group ◽

Cytolethal Distending Toxin ◽

Whole Genome ◽

Common Marmosets ◽

E Coli ◽

Cytotoxic Necrotizing Factor ◽

Inflammatory Bowel

AbstractCyclomodulins are virulence factors that modulate cellular differentiation, apoptosis, and proliferation. These include colibactin (pks), cytotoxic necrotizing factor (cnf), and cytolethal distending toxin (cdt). Pathogenic pks+, cnf+, and cdt+ E. coli strains are associated with inflammatory bowel disease (IBD) and colorectal cancer in humans and animals. Captive marmosets are frequently afflicted with IBD-like disease, and its association with cyclomodulins is unknown. Cyclomodulin-encoding E. coli rectal isolates were characterized using PCR-based assays in healthy and clinically affected marmosets originating from three different captive sources. 139 E. coli isolates were cultured from 122 of 143 marmosets. The pks gene was detected in 56 isolates (40%), cnf in 47 isolates (34%), and cdt in 1 isolate (0.7%). The prevalences of pks+ and cnf+ E. coli isolates were significantly different between the three marmoset colonies. 98% of cyclomodulin-positive E. coli belonged to phylogenetic group B2. Representative isolates demonstrated cyclomodulin cytotoxicity, and serotyping and whole genome sequencing were consistent with pathogenic E. coli strains. However, the presence of pks+, cnf+, or cdt+ E. coli did not correlate with clinical gastrointestinal disease in marmosets. Cyclomodulin-encoding E. coli colonize laboratory common marmosets in a manner dependent on the source, potentially impacting reproducibility in marmoset models.

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Transcriptome of Tumor-Infiltrating T Cells in Colorectal Cancer Patients Uncovered a Unique Gene Signature in CD4+ T Cells Associated with Poor Disease-Specific Survival

Vaccines ◽

10.3390/vaccines9040334 ◽

2021 ◽

Vol 9 (4) ◽

pp. 334

Author(s):

Salman M. Toor ◽

Varun Sasidharan Nair ◽

Reem Saleh ◽

Rowaida Z. Taha ◽

Khaled Murshed ◽

...

Keyword(s):

Colorectal Cancer ◽

T Cells ◽

T Cell Activation ◽

Cd4 T Cells ◽

Poor Prognosis ◽

Gene Signature ◽

The Cancer Genome Atlas ◽

Disease Specific Survival ◽

Unique Gene ◽

Disease Specific

Colorectal cancer (CRC) is influenced by infiltration of immune cell populations in the tumor microenvironment. While elevated levels of cytotoxic T cells are associated with improved prognosis, limited studies have reported associations between CD4+ T cells and disease outcomes. We recently performed transcriptomic profiling and comparative analyses of sorted CD4+ and CD8+ tumor-infiltrating lymphocytes (TILs) from bulk tumors of CRC patients with varying disease stages. In this study, we compared the transcriptomes of CD4+ with CD8+ TILs. Functional annotation pathway analyses revealed the downregulation of inflammatory response-related genes, while T cell activation and angiogenesis-related genes were upregulated in CD4+ TILs. The top 200 deregulated genes in CD4+ TILs were aligned with the cancer genome atlas (TCGA) CRC dataset to identify a unique gene signature associated with poor prognosis. Moreover, 69 upregulated and 20 downregulated genes showed similar trends of up/downregulation in the TCGA dataset and were used to calculate “poor prognosis score” (ppScore), which was significantly associated with disease-specific survival. High ppScore patients showed lower expression of Treg-, Th1-, and Th17-related genes, and higher expression of Th2-related genes. Our data highlight the significance of T cells within the TME and identify a unique candidate prognostic gene signature for CD4+ TILs in CRC patients.

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High prevalence of TP53 loss and whole-genome doubling in early-onset colorectal cancer

Experimental & Molecular Medicine ◽

10.1038/s12276-021-00583-1 ◽

2021 ◽

Author(s):

Jeong Eun Kim ◽

Jaeyong Choi ◽

Chang-Ohk Sung ◽

Yong Sang Hong ◽

Sun Young Kim ◽

...

Keyword(s):

Colorectal Cancer ◽

Early Onset ◽

Large Scale ◽

Late Onset ◽

Age Groups ◽

The Cancer Genome Atlas ◽

Whole Genome ◽

Genome Doubling ◽

Whole Genome Doubling ◽

Early Onset Colorectal Cancer

AbstractThe global incidence of early-onset colorectal cancer (EO-CRC) is rapidly rising. However, the reason for this rise in incidence as well as the genomic characteristics of EO-CRC remain largely unknown. We performed whole-exome sequencing in 47 cases of EO-CRC and targeted deep sequencing in 833 cases of CRC. Mutational profiles of EO-CRC were compared with previously published large-scale studies. EO-CRC and The Cancer Genome Atlas (TCGA) data were further investigated according to copy number profiles and mutation timing. We classified colorectal cancer into three subgroups: the hypermutated group consisted of mutations in POLE and mismatch repair genes; the whole-genome doubling group had early functional loss of TP53 that led to whole-genome doubling and focal oncogene amplification; the genome-stable group had mutations in APC and KRAS, similar to conventional colon cancer. Among non-hypermutated samples, whole-genome doubling was more prevalent in early-onset than in late-onset disease (54% vs 38%, Fisher’s exact P = 0.04). More than half of non-hypermutated EO-CRC cases involved early TP53 mutation and whole-genome doubling, which led to notable differences in mutation frequencies between age groups. Alternative carcinogenesis involving genomic instability via loss of TP53 may be related to the rise in EO-CRC.

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Clinical benefit of whole genome and transcriptome analysis (WGTA) in metastatic colorectal cancer (MCRC): Results from the personalized oncogenomics program (POG)

Annals of Oncology ◽

10.1093/annonc/mdy281.131 ◽

2018 ◽

Vol 29 ◽

pp. viii195

Author(s):

S.L. Liu ◽

J. Loree ◽

D. Renouf ◽

M. Jones ◽

S. Yip ◽

...

Keyword(s):

Colorectal Cancer ◽

Metastatic Colorectal Cancer ◽

Transcriptome Analysis ◽

Clinical Benefit ◽

Whole Genome

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Whole genome transcriptome analysis of the stomach resected in human vertical sleeve gastrectomy: cutting more than calories

Physiological Genomics ◽

10.1152/physiolgenomics.00082.2020 ◽

2021 ◽

Author(s):

William C Dungan ◽

Michael R Garrett ◽

Bradley A. Welch ◽

William J Lawson ◽

Alexandra R Himel ◽

...

Keyword(s):

Body Weight ◽

Sleeve Gastrectomy ◽

Transcriptome Analysis ◽

Gene Signature ◽

Whole Genome ◽

Vertical Sleeve Gastrectomy ◽

Data Set ◽

Tissue Samples ◽

Highly Expressed Genes ◽

A Prospective Study

Background. Vertical sleeve gastrectomy (VSG) is a surgical weight loss procedure that resects 80% of the stomach, creating a tube linking the esophagus to the duodenum. Because of the efficacy and relative simplicity of VSG, it is preferred in the U.S with VSG currently at >61% of bariatric surgeries performed. Surprisingly, there has never been a complete molecular characterization of the human stomach fundus and corpus. Here we compare and contrast the molecular make-up of these regions. Methods. We performed a prospective study to obtain gastric tissue samples from patients undergoing VSG. Paired fundus and corpus samples were obtained Whole genome transcriptome analysis was performed by RNA sequencing, with key findings validated by qPCR. Results. Participants were primarily female (95.8%) and white (79.15%). Mean BMI, body weight, and age were 46.1 kg/m2, 121.6 kg, and 43.29 years, respectively. Overall, 432 gene transcripts were significantly different between the fundus and corpus (p<0.05). A significant correlation was found between the RNAseq data set and qPCR validation, demonstrating robust gene expression differences. Significant genes included: progastricsin, acid chitinase, gastokine 1 and 2 in both fundus and corpus. Of the very highly expressed genes in both regions, 87% were present in both the stomach's fundus and corpus, indicating substantial overlap. Conclusions. Despite significant overlap in the greater curvature gene signature, regional differences exist. Given that the mechanism of VSG is partly unresolved, the potential that the resected tissue may express genes that influence long-term body weight regulation is unknown and could influence VSG outcomes.

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