Search

Background: The association between microbes and cancer has been reported repeatedly; however, it is not clear if molecular tumour properties are connected to specific microbial colonisation patterns. This is due mainly to the current technical and analytical strategy limitations to characterise tumour-associated bacteria., Methods: Here, we propose an approach to detect bacterial signals in human RNA sequencing data and associate them with the clinical and molecular properties of the tumours. The method was tested on public datasets from The Cancer Genome Atlas, and its accuracy was assessed on a new cohort of colorectal cancer patients., Results: Our analysis shows that intratumoural microbiome composition is correlated with survival, anatomic location, microsatellite instability, consensus molecular subtype and immune cell infiltration in colon tumours. In particular, we find Faecalibacterium prausnitzii, Coprococcus comes, Bacteroides spp., Fusobacterium spp. and Clostridium spp. to be strongly associated with tumour properties., Conclusions: We implemented an approach to concurrently analyse clinical and molecular properties of the tumour as well as the composition of the associated microbiome. Our results may improve patient stratification and pave the path for mechanistic studies on microbiota-tumour crosstalk., (© 2023. The Author(s).)

CD8 + T cells are a major prognostic determinant in solid tumors, including colorectal cancer (CRC). However, understanding how the interplay between different immune cells impacts on clinical outcome is still in its infancy. Here, we describe that the interaction of tumor infiltrating neutrophils expressing high levels of CD15 with CD8 + T effector memory cells (T EM ) correlates with tumor progression. Mechanistically, stromal cell-derived factor-1 (CXCL12/SDF-1) promotes the retention of neutrophils within tumors, increasing the crosstalk with CD8 + T cells. As a consequence of the contact-mediated interaction with neutrophils, CD8 + T cells are skewed to produce high levels of GZMK, which in turn decreases E-cadherin on the intestinal epithelium and favors tumor progression. Overall, our results highlight the emergence of GZMK high CD8 + T EM in non-metastatic CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics., (© 2022. The Author(s).)

Following progression on first-line platinum and fluoropyrimidine-based chemotherapy, prognosis for advanced gastric cancer patients is extremely poor. Thus, new and effective treatments are required. Based on positive results of recent randomized controlled trials, second-line monochemotherapies with either irinotecan or taxanes confer a median overall survival of approximately 5 months in gastro-esophageal and gastric adenocarcinoma. Combination of weekly paclitaxel and ramucirumab, a novel anti-angiogenic VEGFR2 antibody, pushes the overall survival up to over 9.5 months, whereas apatinib, a novel oral VEGFR2 tyrosine kinase inhibitor, seems to be promising in heavily pretreated patients. In contrast, the role of EGFR/HER2 and mTOR inhibitors is controversial. Studies are heterogeneous for tumor population, geographical areas, quality of life assessment, type of first-line therapy and response to that, making clinical practice application of the trial results difficult. Furthermore, sustainability is challenging due to high cost of novel biotherapies., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)