Location and condition based reconstruction of colon cancer microbiome from human RNA sequencing data.

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.

GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in non-metastatic colorectal tumors and predict poor clinical outcome.

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 (TEM) 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 GZMKhigh CD8+ TEM 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.

Personality Factors in Colorectal Cancer: A Systematic Review.

Background: The role of personality in cancer incidence and development has been studied for a long time. As colorectal cancer (CRC) is one of the most prevalent cancer types and linked with lifestyle habits, it is important to better understand its psychological correlates, in order to design a more specific prevention and intervention plan. The aim of this systematic review is to analyze all the studies investigating the role of personality in CRC incidence. Methods: All studies on CRC and personality up to November 2020 were scrutinized according to the Cochrane Collaboration and the PRISMA statements. Selected studies were additionally evaluated for the Risk of Bias according to the Newcastle-Ottawa Scale (NOS). Results: Eight studies met the inclusion criteria and were eventually included in this review. Two main constructs have been identified as potential contributors of CRC incidence: emotional regulation (anger) and relational style (egoism). Conclusion: Strong conclusions regarding the influence of personality traits on the incidence of CRC are not possible, because of the small number and the heterogeneity of the selected studies. Further research is needed to understand the complexity of personality and its role in the incidence of CRC and the interaction with other valuable risk factors.

Systemic therapy beyond first-line in advanced gastric cancer: An overview of the main randomized clinical trials.

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.