Taylor, W. | Search bioRxiv

bioRxiv2019

Chronic circadian disruption modulates breast cancer cell stemness and their immune microenvironment to drive metastasis in mice

Breast cancer is the most common type and one of the major causes of cancer death in woman worldwide. Epidemiological studies have established a link between night shift work and increased cancer risk, suggesting that circadian disruption may interfere with carcinogenesis. We aim to shed light on the effect of chronic jetlag on mammary tumour development. Therefore, we used a mouse model of spontaneous mammary tumorigenesis that we exposed to chronic circadian disruption. We observed that circadian disruption significantly increases cancer cell dissemination and metastasis. It also enhances the stemness and tumour-initiating potential of tumour cells and creates an immunosuppressive shift in the tumour microenvironment. We finally showed that all these defects can be corrected by the use of a CXCR2 inhibitor. Altogether, our data provide a conceptual framework to better understand and manage the effects of chronic circadian disruption on breast cancer progression.

cancer biology↗

bioRxiv2019

MinION Sequencing of colorectal cancer tumour microbiomes - a comparison with amplicon-based and RNA-Sequencing

Recent evidence suggests a role for the gut microbiome in the development and progression of colorectal cancer. In this study we compare MinION sequencing with meta-transcriptomics and amplicon-based sequencing for microbiome analysis of colorectal tumour tissue samples. DNA and RNA were extracted from 11 colorectal tumour samples. RNA-Sequencing, 16S rRNA amplicon sequencing and MinION genomic sequencing was carried out and resulting data used as input for taxonomic classification using Kraken2. Taxonomic concordance between the three platforms at different taxonomic levels was tested on a per sample basis. The average number of reads per sample using RNA-Sequencing was more than 129 times that generated using MinION sequencing. However, the average read length of MinION sequences was more than 13 times that of RNA or 16S rRNA amplicon sequencing. 16S sequencing was less informative beyond the genus level, and both RNA-Sequencing and MinION sequencing could detect more phyla and genera in the same samples, compared to 16S sequencing. Long-read sequences generated using MinION sequencing can compensate for low numbers of reads for bacterial classification. MinION sequencing can discriminate between bacterial strains and plasmids and shows potential as a tool for microbiome sequencing of colorectal cancers in a clinical setting.

microbiology↗