ABSTRACT
<p><b>OBJECTIVE</b>To compare fecal microbiota and metabolites between colorectal cancer (CRC) patients and healthy population.</p><p><b>METHODS</b>Feces from fifteen CRC patients and twelve normal people were analyzed by using pyrosequencing and gas chromatography mass spectrometry(GC/MS).</p><p><b>RESULTS</b>There were no significant differences in the overall microbial community structure associated with the disease state, but 18 bacterial genera were underrepresented or overrepresented in the CRC samples. GC-MS profiling revealed higher concentrations for 9 kinds of amino acids and metabolites of short-chain fatty acids, lower concentrations for 3 kinds of unsaturated fatty acids and 2 kinds of glycerin and ursodeoxycholic acid in stool samples from CRC patients. Correlative analysis between the combined datasets revealed some potential relationships between stool metabolites and certain bacterial species.</p><p><b>CONCLUSIONS</b>There are significant differences in fecal metabolites and the relative abundance of certain types of bacteria between CRC patients and healthy people, which can provide insight into microbial functions occurring in a cancer environment and will help direct future mechanism studies.</p>