Association of HLA diversity with the risk of 25 cancers in the UK Biobank

BACKGROUND

The human leukocyte antigen (HLA) is a highly polymorphic region, and HLA diversity may play a role in presenting tumour-associated peptides and inducing immune responses. However, the effect of HLA diversity on cancers has not been fully assessed. We aimed to explore the role of HLA diversity on cancer development.

METHODS

A pan-cancer analysis was performed to evaluate the effect of HLA diversity, measured by HLA heterozygosity and HLA evolutionary divergence (HED), on the susceptibility of 25 cancers in the UK Biobank.

FINDINGS

We observed that the diversity of HLA class II locus was associated with a lower risk of lung cancer (OR_hetero = 0.94, 95% CI = 0.90-0.97, P = 1.29 × 10^-4) and head and neck cancer (OR_hetero = 0.91, 95% CI = 0.86-0.96, P = 1.56 × 10^-3). Besides, a lower risk of non-Hodgkin lymphoma was associated with an increased diversity of HLA class I (OR_hetero = 0.92, 95% CI = 0.87-0.98, P = 8.38 × 10^-3) and class II locus (OR_hetero = 0.89, 95% CI = 0.86-0.92, P = 1.65 × 10^-10). A lower risk of Hodgkin lymphoma was associated with the HLA class I diversity (OR_hetero = 0.85, 95% CI = 0.75-0.96, P = 0.011). The protective effect of HLA diversity was mainly observed in pathological subtypes with higher tumour mutation burden, such as lung squamous cell carcinoma (P = 9.39 × 10^-3) and diffuse large B cell lymphoma (P_{class I} = 4.12 × 10^-4; P_{class Ⅱ} = 4.71 × 10^-5), as well as the smoking subgroups of lung cancer (P = 7.45 × 10^-5) and head and neck cancer (P = 4.55 × 10^-3).

INTERPRETATION

We provided a systematic insight into the effect of HLA diversity on cancers, which might help to understand the etiological role of HLA on cancer development.

FUNDING

This study was supported by grants from the National Natural Science Foundation of China (82273705, 82003520); the Basic and Applied Basic Research Foundation of Guangdong Province, China (2021B1515420007); the Science and Technology Planning Project of Guangzhou, China (201804020094); Sino-Sweden Joint Research Programme (81861138006); the National Natural Science Foundation of China (81973131, 81903395, 81803319, 81802708).

Specific Class I HLA Supertypes but Not HLA Zygosity or Expression Are Associated with Outcomes following HLA-Matched Allogeneic Hematopoietic Cell Transplant: HLA Supertypes Impact Allogeneic HCT Outcomes

Maximizing the probability of antigen presentation to T cells through diversity in HLAs can enhance immune responsiveness and translate into improved clinical outcomes, as evidenced by the association of heterozygosity and supertypes at HLA class I loci with improved survival in patients with advanced solid tumors treated with immune checkpoint inhibitors. We investigated the impact of HLA heterozygosity, supertypes, and surface expression on outcomes in adult and pediatric patients with acute myeloid leukemia (AML), myelodysplastic syndrome, acute lymphoblastic leukemia, and non-Hodgkin lymphoma who underwent 8/8 HLA-matched, T cell replete, unrelated, allogeneic hematopoietic cell transplant (HCT) from 2000 to 2015 using patient data reported to the Center for International Blood and Marrow Transplant Research. HLA class I heterozygosity and HLA expression were not associated with overall survival, relapse, transplant-related mortality (TRM), disease-free survival (DFS), and acute graft-versus-host disease following HCT. The HLA-B62 supertype was associated with decreased TRM in the entire patient cohort (hazard ratio [HR], 0.79; 95% CI, 0.69 to 0.90; P = .00053). The HLA-B27 supertype was associated with worse DFS in patients with AML (HR = 1.21; 95% CI, 1.10 to 1.32; P = .00005). These findings suggest that the survival benefit of HLA heterozygosity seen in solid tumor patients receiving immune checkpoint inhibitors does not extend to patients undergoing allogeneic HCT. Certain HLA supertypes, however, are associated with TRM and DFS, suggesting that similarities in peptide presentation between supertype members play a role in these outcomes. Beyond implications for prognosis following HCT, these findings support the further investigation of these HLA supertypes and the specific immune peptides important for transplant outcomes.