In this study, Aviles-Jimenez and co-workers aimed to characterize microbiota of the gastric mucosa as its progress to intestinal type of cancer. To do that, they analysed gastric tissue in patients with non-atrophic gastritis (NAG), intestinal metaplasia (IM) and intestinal-type gastric cancer (GC). After performing genetic analyses on the samples, the researchers quantified a low bacterial diversity in all samples, ranged form 8 (in GC patients) to 57 (in NAG), with IM as an intermediate group. Also, they found that Firmicutes and Proteobacteria represented almost the 70% of phyla in all samples. Interestingly, they observed a gradual decrease in gastric microbiota profile from NAG to IM to GC. In particular, a significant difference in the microbiota abundance was found between the NAG and GC samples.
Thus, the authors suggested that these results would indicate that changes in the gastric mucosa as patients move to preneoplasia and to cancer rendered the environment more restrictive to bacterial growth.