Work

Single-Cell Atlas of Non-Functioning Gonadotroph Tumors and Anterior Pituitary Reveals Lineage Infidelity and Clinically Associated Transcriptional Programs

Year: 2026

Type: preprint

Abstract: Background Non-functioning gonadotroph (NFG) tumors are the most common type of non-functioning pituitary adenomas and cause significant morbidity through mass effect. The molecular programs that distinguish NFG tumor cells from normal gonadotrophs and underlie tumor growth remain poorly understood. The aim of this study was to define transcriptional differences between NFG tumors and the normal anterior pituitary gland (APG) at single-cell resolution and to identify programs associated with tumor growth. Methods We performed single-cell/nucleus RNA-sequencing of 21 NFG tumors and 8 APG samples, followed by integrative analyses of differential gene expression, regulatory networks, and cell–cell communication. Results We profiled 77,342 APG cells and 152,649 NFG tumor cells. Within the APG, we identified novel marker genes for each neuroendocrine cell type and distinct transcriptional signatures of anterior and posterior pituitary stem cell populations. Compared with normal gonadotrophs, tumor cells shared a core transcriptomic signature conserved across samples despite inter-tumor heterogeneity. Many conserved genes were markers of non-gonadotroph neuroendocrine and stem cells, suggesting that lineage infidelity is a recurrent feature of NFGs. Pseudobulk profiling identified genes positively correlated with tumor volume, including the known oncogenes CAD , BRF2 , and SOX12 . Finally, tumors showed increased proportions of myeloid, endothelial, and mural cells and crosstalk between tumor, immune, and stromal populations. Conclusions This study defines transcriptomic signatures of cell identity in the normal APG and NFG tumors. Our findings reveal programs associated with NFG lineage infidelity and tumor growth, highlighting candidate predictors of patient outcomes and potential therapeutic targets. Key Points Single-cell analysis characterizes transcriptomic landscape of APG and NFG tumors. Differential expression analysis identifies lineage infidelity in NFG tumors. Transcriptomic profiling identifies genes positively correlated with tumor volume. Importance of the Study This study sequenced more than 152,000 transcriptomes from 21 nonfunctioning gonadotroph (NFG) tumors and 77,000 transcriptomes from the normal adult human anterior pituitary gland (APG). Differential expression analysis of APG cells identified novel marker genes for each neuroendocrine cell type and defined distinct transcriptional signatures of anterior and posterior pituitary stem cells. Comparing these APG cell-type markers with genes differentially expressed in tumor cells revealed that NFGs display transcriptomic characteristics of non-gonadotroph neuroendocrine cells. Pseudobulk profiling identified FSHB -high and FSHB -low tumors with distinct transcriptional programs, as well as genes positively correlated with tumor volume. We also characterized the NFG tumor microenvironment. Overall, this study provides novel insight into NFG biology, while markers of lineage infidelity and tumor growth may serve as candidate predictors of patient outcomes and potential therapeutic targets. Importantly, these data provide an essential reference dataset for future studies of NFGs and the APG.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.09.17.752250