Benign prostatic hyperplasia (BPH) is a progressive disease in elderly men, but potential factors accelerating its progression remain largely unknown. The aim of this study was to elucidate the factors affecting BPH progression by understanding the complex mechanisms causing early- progressed BPH, which progresses rapidly and requires surgical intervention before the age of 50. Three groups of human prostate tissue samples, from patients with early-progressed BPH, age-matched prostate and elderly BPH tissues, were collected (n = 25 each). We compared these tissues to determine the histologic features and molecular mechanisms underlying BPH progression. We found that early-progressed BPH samples were characterised by aberrant stromal hyper-proliferation, collagen deposition and increased M2 macrophage infiltration, compared to those from age-matched prostate and elderly BPH tissues. The M2 macrophage–fibroblast co-culture system demonstrated that the myofibroblast phenotypes were strongly induced only in fibroblasts from the early-progressed BPH samples, while the co-cultured M2 macrophages expressed high levels of pro-fibrotic cytokines, such as IL4 and TGFβ1. M2 macrophage-derived IL4, but not TGFβ1, selectively induced the myofibroblast phenotype through the JAK/STAT6, PI3K/AKT and MAPK/ERK signalling pathways in the early-progressed BPH prostate fibroblasts. Taken together, our results indicate that induction of the myofibroblast phenotype may lead to BPH progression through M2 macrophage-mediated IL4 signalling, and that IL4 may represent a potential therapeutic target, allowing the prevention of M2 macrophage activation and fibroblast-to-myofibroblast differentiation.

Previous studies by our group have shown that low intra-prostatic dihydrotestosterone (DHT) induced BPH epithelial cells (BECs) to recruit CD8+ T cells. However, the influence of the recruited CD8+ T cells on BECs under a low androgen level is still unknown. Here, we found CD8+ T cells have the capacity to promote proliferation of BECs in low androgen condition. Mechanism dissection revealed that interaction between CD8+ T cells and BECs through secretion of CCL5 might promote the phosphorylation of STAT5 and a higher expression of CCND1 in BECs. Suppressed CCL5/STAT5 signals via CCL5 neutralizing antibody or STAT5 inhibitor Pimozide led to reverse CD8+ T cell-enhanced BECs proliferation. IHC analysis from Finasteride treated patients showed PCNA expression in BECs was highly correlated to the level of CD8+ T cell infiltration and the expression of CCL5. Consequently, our data indicated infiltrating CD8+ T cells could promote the proliferation of BECs in low androgen condition via modulation of CCL5/STAT5/CCND1 signaling. The increased secretion of CCL5 from the CD8+ T cells/BECs interaction might help BECs survive in a low DHT environment. Targeting these signals may provide a new potential therapeutic approach to better treat BPH patients who failed the therapy of 5α-reductase inhibitors.

Benign prostatic hyperplasia (BPH) is the most common and progressive urological disease in elderly men worldwide. Epidemiological studies have suggested that the speed of disease progression varies among individuals, while the pathophysiological mechanisms of accelerated clinical progression in some BPH patients remain to be elucidated. In this study, we defined patients with BPH as belonging to the accelerated progressive group (transurethral resection of the prostate [TURP] surgery at ≤50 years old), normal-speed progressive group (TURP surgery at ≥70 years old), or non-progressive group (age ≤50 years old without BPH-related surgery). We enrolled prostate specimens from the three groups of patients and compared these tissues to determine the histopathological characteristics and molecular mechanisms underlying BPH patients with accelerated progression. We found that the main histopathological characteristics of accelerated progressive BPH tissues were increased stromal components and prostatic fibrosis, which were accompanied by higher myofibroblast accumulation and collagen deposition. Mechanism dissection demonstrated that these accelerated progressive BPH tissues have higher expression of the CYP19 and G protein-coupled estrogen receptor (GPER) with higher estrogen biosynthesis. Estrogen functions via GPER/Gαi signaling to modulate the EGFR/ERK and HIF-1α/TGF-β1 signaling to increase prostatic stromal cell proliferation and prostatic stromal fibrosis. The increased stromal components and prostatic fibrosis may accelerate the clinical progression of BPH. Targeting this newly identified CYP19/estrogen/GPER/Gαi signaling axis may facilitate the development of novel personalized therapeutics to better suppress the progression of BPH.

Background Transmission of malignancy is a notable problem that cannot always be absolutely predicted at the time of transplantation. In particular, donor-derived transmission of synovial sarcoma in solid-organ transplantation is a rare but catastrophic event. Case presentation We are the first to report three cases of synovial sarcoma transmitted from a single multi-organ donor in China. The donor died of respiratory failure caused by an intrathoracic tumor, which was diagnosed as benign at the time of donation. All three recipients developed synovial sarcoma 3–13 months after transplantation; all three cases were confirmed to be donor transmitted. The liver transplant recipient died of tumor metastasis after partial-allograft hepatectomy. The two renal-transplant recipients survived after comprehensive therapy, including allograft nephrectomy, withdrawal of immunosuppressants and targeted therapy with anlotinib. Conclusions This report highlights the importance of detailed donor assessment, close follow-up and timely treatment of unexpected donor-transmitted malignancy. Although pathology is the most important evidence for the exclusion of donors for malignant potential, it should be combined with tumor type, tumor size and speed of growth. Organs from donors with malignant potential should be discarded. Allograft nephrectomy should be considered after confirmation of renal-allograft synovial sarcoma. Anlotinib for synovial sarcoma seems to be effective and well tolerated during long-term follow-up.