Single‐cell analysis of mouse and human prostate reveals novel fibroblasts with specialized distribution and microenvironment interactions

Abstract

Stromal–epithelial interactions are critical to the morphogenesis, differentiation, and homeostasis of the prostate, but the molecular identity and anatomy of discrete stromal cell types is poorly understood. Using single‐cell RNA sequencing, we identified and validated the in situ localization of three smooth muscle subtypes (prostate smooth muscle, pericytes, and vascular smooth muscle) and two novel fibroblast subtypes in human prostate. Peri‐epithelial fibroblasts (APOD+) wrap around epithelial structures, whereas interstitial fibroblasts (C7+) are interspersed in extracellular matrix. In contrast, the mouse displayed three fibroblast subtypes with distinct proximal–distal and lobe‐specific distribution patterns. Statistical analysis of mouse and human fibroblasts showed transcriptional correlation between mouse prostate (C3+) and urethral (Lgr5+) fibroblasts and the human interstitial fibroblast subtype. Both urethral fibroblasts (Lgr5+) and ductal fibroblasts (Wnt2+) in the mouse contribute to a proximal Wnt/Tgfb signaling niche that is absent in human prostate. Instead, human peri‐epithelial fibroblasts express secreted WNT inhibitors SFRPs and DKK1, which could serve as a buffer against stromal WNT ligands by creating a localized signaling niche around individual prostate glands. We also identified proximal–distal fibroblast density differences in human prostate that could amplify stromal signaling around proximal prostate ducts. In human benign prostatic hyperplasia, fibroblast subtypes upregulate critical immunoregulatory pathways and show distinct distributions in stromal and glandular phenotypes. A detailed taxonomy of leukocytes in benign prostatic hyperplasia reveals an influx of myeloid dendritic cells, T cells and B cells, resembling a mucosal inflammatory disorder. A receptor–ligand interaction analysis of all cell types revealed a central role for fibroblasts in growth factor, morphogen, and chemokine signaling to endothelia, epithelia, and leukocytes. These data are foundational to the development of new therapeutic targets in benign prostatic hyperplasia. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

5‐Alpha reductase inhibitors induce a prostate luminal to club cell transition in human benign prostatic hyperplasia

“…The Visium platform produces a transcriptomic profile of intact tissue sections by capturing mRNA on an underlying grid of equidistant dots, each containing approximately 5 or 6 cells. Using the Seurat label transfer function [11], the transcript signature of each capture dot was assigned a probability score for each of 11 discrete cell types described in our previously published human prostate reference dataset [9]. The cell type corresponding to the highest probability score was assigned as the identity of the capture dot (Figure 1A).…”

“…cDNA was transferred from the slide for library preparation and subsequent sequencing using a Nova-Seq 6000 sequencer (Illumina, San Diego, CA, USA). Data were merged using Seurat [8], and cell type identities from our normal prostate reference dataset [9] were assigned to the Visium capture dots. Supplementary tables contain sequencing metrics and gene lists for custom scores (supplementary material, Tables S3 and S4, respectively).…”

“…Single cells were loaded onto the 10Â Genomics chromium controller. Single cell data were analyzed as described previously [9]. Cell types were identified using Seurat's label transfer method [11] with the same reference used for the Visium data [9].…”

“…Single cell data were analyzed as described previously [9]. Cell types were identified using Seurat's label transfer method [11] with the same reference used for the Visium data [9]. Sequencing metrics can be found in supplementary material, Table S3.…”

Male Lower Urinary Tract Dysfunction: An Underrepresented Endpoint in Toxicology Research

“…The human prostate is a spherical gland encapsulated by a fibromuscular sheath known as the prostatic capsule [24,96,99]. The base of the prostate is adjacent to the bladder and the prostatic urethra courses through its center [100].…”