A Review of GC-Based Analysis of Non-Invasive Biomarkers of Colorectal Cancer and Related Pathways

Abstract

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world. In Europe, it is the second most common cause of cancer-related deaths. With the advent of metabolomics approaches, studies regarding the investigation of metabolite profiles related to CRC have been conducted, aiming to serve as a tool for early diagnosis. In order to provide further information about the current status of this field of research, 21 studies were systematically reviewed, regarding their main findings and analytical aspects. A special focus was given to the employment of matrices obtained non-invasively and the use of gas chromatography as the analytical platform. The relationship between the reported volatile and non-volatile biomarkers and CRC-related metabolic alterations was also explored, demonstrating that many of these metabolites are connected with biochemical pathways proven to be involved in carcinogenesis. The most commonly reported CRC indicators were hydrocarbons, aldehydes, amino acids and short-chain fatty acids. These potential biomarkers can be associated with both human and bacterial pathways and the analysis based on such species has the potential to be applied in the clinical practice as a low-cost screening method.

Metabolic Profiling of VOCs Emitted by Bacteria Isolated from Pressure Ulcers and Treated with Different Concentrations of Bio-AgNPs

“…The decarboxylation of fatty acids can give rise to corresponding alkanes [ 18 ]. Apart from this, alkanes can be obtained in the course of peroxidation of a fatty acid followed by its cleavage and posterior reduction [ 66 ]. In this sense, elevation of branched species can be linked to the degradation of constituting lipids.…”

Biomarkers to Detect Early-Stage Colorectal Cancer

“…The growing number of studies looking for nonvolatile CRC-associated metabolites suggests these will also be used in the future to triage symptomatic patients [ 14 , 95 , 96 ]. However, this approach will not be without challenges.…”

Comparison of Surgical Outcomes of Fistulotomy and Fistulectomy for the Management of Simple Low Fistula-In-ANO

“…In surgery Anal Fistulas are one of the most common benign conditions. Usually defined as chronic abnormal communication that is lined by granulation tissue to some extent, which connects the anorectal lumen to an external opening on the perineal skin (1) . The incidence of fistulas is about 9 per 100,000 population per year in western Europe (1) and the patients most commonly affected are in third, fourth and fifth decades of their life.…”