biostudies-literatureUnknown127(10)Ingebriktsen LM<h4>Background and objective</h4>Breast cancer (BC) diagnosed at ages <40 years presents with more aggressive tumour phenotypes and poorer clinical outcome compared to older BC patients. Here, we explored transcriptional BC alterations to gain a better understanding of age-related tumour biology, also subtype-stratified.<h4>Methods</h4>We studied publicly available global BC mRNA expression (n = 3999) and proteomics data (n = 113), exploring differentially expressed genes, enriched gene sets, and gene networks in the young compared to older patients.<h4>Results</h4>We identified transcriptional patterns reflecting increased proliferation and oncogenic signalling in BC of the young, also in subtype-stratified analyses. Six up-regulated hub genes built a novel age-related score, significantlBritish journal of cancer1865-1875https://www.ebi.ac.uk/biostudies/studies/S-EPMC9643541biostudies-literatureA novel age-related gene expression signature associates with proliferation and disease progression in breast cancer.PMC9643541Wik EIngebriktsen LMAkslen LAFinne KfalseA novel age-related gene expression signature associates with proliferation and disease progression in breast cancer.<h4>Background and objective</h4>Breast cancer (BC) diagnosed at ages <40 years presents with more aggressive tumour phenotypes and poorer clinical outcome compared to older BC patients. Here, we explored transcriptional BC alterations to gain a better understanding of age-related tumour biology, also subtype-stratified.<h4>Methods</h4>We studied publicly available global BC mRNA expression (n = 3999) and proteomics data (n = 113), exploring differentially expressed genes, enriched gene sets, and gene networks in the young compared to older patients.<h4>Results</h4>We identified transcriptional patterns reflecting increased proliferation and oncogenic signalling in BC of the young, also in subtype-stratified analyses. Six up-regulated hub genes built a novel age-related score, significantl2022-01-01T00:00:00Z2022 Nov2025-04-18T19:06:37.198Z2025-04-07T06:45:17.075ZS-EPMC96435413599593510.1038/s41416-022-01953-w