Increased Frequency of KRAS Mutations in African Americans Compared with Caucasians in Sporadic Colorectal Cancer

Molecular classification of colorectal cancer is difficult to implement in clinical settings where hundreds of genes are involved, and resources are limited. This study aims to characterize the molecular subtypes of patients with sporadic colorectal cancer based on the three main carcinogenic pathways microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and chromosomal instability (CIN) in a Chilean population. Although several reports have characterized colorectal cancer, most do not represent Latin-American populations. Our study includes 103 colorectal cancer patients who underwent surgery, without neoadjuvant treatment, in a private hospital between 2008 and 2017. MSI, CIN, and CIMP status were assessed. Frequent mutations in KRAS, BRAF, and PIK3CA genes were analyzed by Sanger sequencing, and statistical analysis was performed by Fisher’s exact and/or chi-square test. Survival curves were estimated with Kaplan–Meier and log-rank test. Based on our observations, we can classify the tumors in four subgroups, Group 1: MSI-high tumors (15%) are located in the right colon, occur at older age, and 60% show a BRAF mutation; Group 2: CIN-high tumors (38%) are in the left colon, and 26% have KRAS mutations. Group 3: [MSI/CIN/CIMP]-low/negative tumors (30%) are left-sided, and 39% have KRAS mutations; Group 4: CIMP-high tumors (15%) were more frequent in men and left side colon, with 27% KRAS and 7% presented BRAF mutations. Three percent of patients could not be classified. We found that CIMP-high was associated with a worse prognosis, both in MSI-high and MSI stable patients (p = 0.0452). Group 3 (Low/negative tumors) tend to have better overall survival compared with MSI-high, CIMP-high, and CIN-high tumors. This study contributes to understanding the heterogeneity of tumors in the Chilean population being one of the few characterizations performed in Latin-America. Given the limited resources of these countries, these results allow to improve molecular characterization in Latin-American colorectal cancer populations and confirm the possibility of using the three main carcinogenic pathways to define therapeutic strategies.

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Heterogeneity of KRAS, NRAS, PIK3CA and BRAF mutational status in primary tumour, lymph nodes and liver metastases in sporadic colorectal cancer

10.26226/morressier.5b4709896f4cb30010951e82 ◽

2018 ◽

Author(s):

Sofia Del Carmen

Keyword(s):

Colorectal Cancer ◽

Lymph Nodes ◽

Liver Metastases ◽

Primary Tumour ◽

Sporadic Colorectal Cancer ◽

Mutational Status

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Clinicopathologic Features of Sporadic Colorectal Cancer with MLH1/MSH2 Loss of Expression - Reduced Likelihood of Metastases

Journal of the Korean Society of Coloproctology ◽

10.3393/jksc.2008.24.3.175 ◽

2008 ◽

Vol 24 (3) ◽

pp. 175 ◽

Cited By ~ 3

Author(s):

Ji Won Park ◽

Hee Jin Chang ◽

Kyung Hae Jung ◽

Dae Yong Kim ◽

Dae Kyung Sohn ◽

...

Keyword(s):

Colorectal Cancer ◽

Sporadic Colorectal Cancer ◽

Clinicopathologic Features

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Faculty Opinions recommendation of Prognostic significance of lymphovascular invasion in sporadic colorectal cancer.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.3403956.3098054 ◽

2010 ◽

Author(s):

Heidi K Chua

Keyword(s):

Colorectal Cancer ◽

Lymphovascular Invasion ◽

Prognostic Significance ◽

Sporadic Colorectal Cancer

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INVESTIGATION KRAS MUTATION IN CIRCULATION TUMOR DNA IN DIFFERENT STAGES OF COLORECTAL CANCER

Problems in oncology ◽

10.37469/0507-3758-2019-65-5-701-707 ◽

2019 ◽

Vol 65 (5) ◽

pp. 701-707

Author(s):

Vitaliy Shubin ◽

Yuriy Shelygin ◽

Sergey Achkasov ◽

Yevgeniy Rybakov ◽

Aleksey Ponomarenko ◽

...

Keyword(s):

Colorectal Cancer ◽

Plasma Volume ◽

Kras Mutation ◽

Stage Iv ◽

Circulating Tumor Dna ◽

Stage Ii ◽

Kras Gene ◽

Kras Mutations ◽

Droplet Pcr ◽

Tumor Dna

To determine mutations in the plasma KRAS gene in patients with colorectal cancer was the aim of this study. The material was obtained from 44 patients with colorectal cancer of different stages (T1-4N0-2bM0-1c). Plasma for the presence of KRAS gene mutation in circulating tumor DNA was investigated using digital droplet polymerase chain reaction (PCR). KRAS mutations in circulating tumor DNA isolated from 1 ml of plasma were detected in 13 (30%) patients with cancer of different stages. Of these, with stage II, there were 3 patients, with III - 5 and with IV - 5. Patients who did not have mutations in 1 ml of plasma were analyzed for mutations of KRAS in circulating tumor DNA isolated from 3 ml of plasma. Five more patients with KRAS mutations were found with II and III stages. The highest concentrations of circulating tumor DNA with KRAS mutation were found in patients with stage IV. The increase in plasma volume to 3 ml did not lead to the identification of mutations in I stage. This study showed that digital droplet PCR allows identification of circulating tumor DNA with the KRAS mutations in patients with stage II-IV of colon cancer. The results can be used to determine the degree of aggressiveness of the tumor at different stages of the disease, but not the 1st, and it is recommended to use a plasma volume of at least 3 ml.

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Biomarkers for Early Detection of Colitis-associated Colorectal Cancer - Current Concepts, Future Trends

Current Drug Targets ◽

10.2174/1389450121666200220123844 ◽

2020 ◽

Vol 22 (1) ◽

pp. 137-145

Author(s):

Tomasz Mackiewicz ◽

Aleksander Sowa ◽

Jakub Fichna

Keyword(s):

Colorectal Cancer ◽

Early Detection ◽

Cancer Development ◽

Sporadic Colorectal Cancer ◽

Future Trends ◽

Significant Progress ◽

Current Standard ◽

Risk Of Cancer ◽

Histological Testing ◽

Made In

: Colitis-associated colorectal cancer (CAC) remains a critical complication of ulcerative colitis (UC) with mortality of approximately 15%, which makes early CAC diagnosis crucial. The current standard of surveillance, with repetitive colonoscopies and histological testing of biopsied mucosa samples is burdensome and expensive, and therefore less invasive methods and reliable biomarkers are needed. Significant progress has been made thanks to continuous extensive research in this field, however no clinically relevant biomarker has been established so far. This review of the current literature presents the genetic and molecular differences between CAC and sporadic colorectal cancer and covers progress made in the early detection of CAC carcinogenesis. It focuses on biomarkers under development, which can be easily tested in samples of body fluids or breath and, once made clinically available, will help to differentiate between progressors (UC patients who will develop dysplasia) from non-progressors and enable early intervention to decrease the risk of cancer development.

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Tracking the Antibody Immunome in Sporadic Colorectal Cancer by Using Antigen Self-Assembled Protein Arrays

Cancers ◽

10.3390/cancers13112718 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2718

Author(s):

María González-González ◽

José María Sayagués ◽

Luis Muñoz-Bellvís ◽

Carlos Eduardo Pedreira ◽

Marcello L. R. de Campos ◽

...

Keyword(s):

Colorectal Cancer ◽

Clinical Utility ◽

Genetic Alterations ◽

Western World ◽

Sporadic Colorectal Cancer ◽

Protein Arrays ◽

Humoral Immune ◽

Cellular Processes ◽

Healthy Donors ◽

Associated Proteins

Sporadic Colorectal Cancer (sCRC) is the third leading cause of cancer death in the Western world, and the sCRC patients presenting with synchronic metastasis have the poorest prognosis. Genetic alterations accumulated in sCRC tumor cells translate into mutated proteins and/or abnormal protein expression levels, which contribute to the development of sCRC. Then, the tumor-associated proteins (TAAs) might induce the production of auto-antibodies (aAb) via humoral immune response. Here, Nucleic Acid Programmable Protein Arrays (NAPPArray) are employed to identify aAb in plasma samples from a set of 50 sCRC patients compared to seven healthy donors. Our goal was to establish a systematic workflow based on NAPPArray to define differential aAb profiles between healthy individuals and sCRC patients as well as between non-metastatic (n = 38) and metastatic (n = 12) sCRC, in order to gain insight into the role of the humoral immune system in controlling the development and progression of sCRC. Our results showed aAb profile based on 141 TAA including TAAs associated with biological cellular processes altered in genesis and progress of sCRC (e.g., FSCN1, VTI2 and RPS28) that discriminated healthy donors vs. sCRC patients. In addition, the potential capacity of discrimination (between non-metastatic vs. metastatic sCRC) of 7 TAAs (USP5, ML4, MARCKSL1, CKMT1B, HMOX2, VTI2, TP53) have been analyzed individually in an independent cohort of sCRC patients, where two of them (VTI2 and TP53) were validated (AUC ~75%). In turn, these findings provided novel insights into the immunome of sCRC, in combination with transcriptomics profiles and protein antigenicity characterizations, wich might lead to the identification of novel sCRC biomarkers that might be of clinical utility for early diagnosis of the tumor. These results explore the immunomic analysis as potent source for biomarkers with diagnostic and prognostic value in CRC. Additional prospective studies in larger series of patients are required to confirm the clinical utility of these novel sCRC immunomic biomarkers.

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