Polymorphisms within Autophagy-Related Genes Influence the Risk of Developing Colorectal Cancer: A Meta-Analysis of Four Large Cohorts

Simple Summary We investigated the influence of autophagy-related variants in modulating colorectal cancer (CRC) risk through a meta-analysis of genome-wide association study (GWAS) data from four large European cohorts. We found that genetic variants within the DAPK2 and ATG5 loci were associated with CRC risk. This study also shed some light onto the functional mechanisms behind the observed associations and demonstrated the impact of DAPK2rs11631973 and ATG5rs546456 polymorphisms on the modulation of host immune responses, blood derived-cell counts and serum inflammatory protein levels, which might be involved in promoting cancer development. No effect of the DAPK2 and ATG5 polymorphisms on the autophagy flux was observed
Acknowledgments: We kindly thank all individuals who agreed to participate in the DACHS, CRCGen, CORSA and Czech Republic Colorectal Cancer studies, as well as all cooperating physicians and students. We thank Hugo Sousa for the collection of healthy donors for the autophagy in vitro studies
Data Availability Statement: The genotype data used in the present study are available from the corresponding authors upon reasonable request. Functional data used in this project have been meticulously catalogued and archived in the BBMRI-NL data infrastructure (https://hfgp.bbmri.nl/, accessed on 13 December 2019) using the MOLGENIS open-source platform for scientific data [52]. This allows flexible data querying and download, including sufficiently rich metadata and interfaces for machine processing (R statistics, REST API) and using FAIR principles to optimise findability, accessibility, interoperability and reusability [53,54].
Funding: This work was partially supported by grants from the Instituto de Salud Carlos III (Madrid, Spain; PI12/02688 and PI17/02256). CORSA was funded by the Austrian Research Promotion Agency (FFG) BRIDGE grant (no. 829675, to Andrea Gsur), the “Herzfelder’sche Familienstiftung” (grant to Andrea Gsur). Czech Republic CCS was funded by GACR grants (18–09709S, 19–10543S and 20–03997S), ProgresQ28/1.LF and UNCE/MED/006 grants. This article is based upon work from COST Action CA17118, supported by COST (European Cooperation in Science and Technology). A.K. is a recipient of a Ramalingaswami Re-Retry Faculty Fellowship (Grant; BT/RLF/Re-entry/38/2017) from the Department of Biotechnology (DBT), Government of India (GOI). V.M. received funding from the Agency for Management of University and Research Grants (AGAUR) of the Catalan Government grant 2017SGR723, the Instituto de Salud Carlos III, co-funded by FEDER funds–a way to build Europe–grants PI14-00613, PI17-00092 and the Spanish Association Against Cancer (AECC) Scientific Foundation grant GCTRA18022MORE. K.H. was supported by European Union Horizon 2020 grant No. 856620. We thank the CERCA Programme, Generalitat de Catalunya for institutional support.
The role of genetic variation in autophagy-related genes in modulating autophagy and cancer is poorly understood. Here, we comprehensively investigated the association of autophagy-related variants with colorectal cancer (CRC) risk and provide new insights about the molecular mechanisms underlying the associations. After meta-analysis of the genome-wide association study (GWAS) data from four independent European cohorts (8006 CRC cases and 7070 controls), two loci, DAPK2 (p = 2.19 × 10−5) and ATG5 (p = 6.28 × 10−4) were associated with the risk of CRC. Mechanistically, the DAPK2rs11631973G allele was associated with IL1 β levels after the stimulation of peripheral blood mononuclear cells (PBMCs) with Staphylococcus aureus (p = 0.002), CD24 + CD38 + CD27 + IgM + B cell levels in blood (p = 0.0038) and serum levels of en-RAGE (p = 0.0068). ATG5rs546456T allele was associated with TNF α and IL1 β levels after the stimulation of PBMCs with LPS (p = 0.0088 and p = 0.0076, respectively), CD14+CD16− cell levels in blood (p = 0.0068) and serum levels of CCL19 and cortisol (p = 0.0052 and p = 0.0074, respectively). Interestingly, no association with autophagy flux was observed. These results suggested an effect of the DAPK2 and ATG5 loci in the pathogenesis of CRC, likely through the modulation of host immune responses.
Instituto de Salud Carlos III (Madrid, Spain; PI12/02688 and PI17/02256)
CORSA was funded by the Austrian Research Promotion Agency (FFG)
BRIDGE grant (no. 829675, to Andrea Gsur)
Czech Republic CCS was funded by GACR grants (18–09709S, 19–10543S and 20–03997S), ProgresQ28/1.LF and UNCE/MED/006 grants
COST Action CA17118, supported by COST (European Cooperation in Science and Technology)
A.K. is a recipient of a Ramalingaswami Re-Retry Faculty Fellowship (Grant; BT/RLF/Re-entry/38/2017) from the Department of Biotechnology (DBT), Government of India (GOI)
Agency for Management of University and Research Grants (AGAUR) of the Catalan Government grant 2017SGR723, the Instituto de Salud Carlos III, co-funded by FEDER funds–a way to build Europe–grants PI14-00613, PI17-00092 and the Spanish Association Against Cancer (AECC) Scientific Foundation grant GCTRA18022MORE.
European Union Horizon 2020 grant No. 856620
CERCA Programme, Generalitat de Catalunya for institutional support