Steroid hormones and hormone antagonists regulate the neural marker neurotrimin in uterine leiomyoma

Abstract

Objective: To characterize the role of steroid hormone and antihormone exposure on neurotrimin (NTM) expression in human leiomyoma and myometrial tissue and cells. Design: Laboratory study of placebo and ulipristal acetate (UPA)-treated patient tissue. In vitro assessment of immortalized myometrial and leiomyoma cell lines after hormone and antihormone exposure. Setting: Academic research center. Patient(s): Not applicable. Interventions(s): Exposure of leiomyoma cell lines to 17b-E 2 , medroxyprogesterone acetate (MPA), UPA, and fulvestrant. Main Outcome Measure(s): Messenger RNA expression quantified with the use of RNASeq analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Protein levels quantified by means of Western blot analysis. Immunohistochemistry (IHC) on placebo-and UPA-treated patient uterine tissue specimens. Result(s): Expression of NTM in human uterine leiomyoma specimens according to RNASeq was increased compared with myometrium (5.22 AE 0.57-fold), which was confirmed with the use of qRT-PCR (1.95 AE 0.05). Furthermore, NTM protein was elevated in leiomyoma tissue compared with matched myometrium (2.799 AE 0.575). IHC revealed increased staining intensity in leiomyoma surgical specimens compared with matched myometrium of placebo patients. Western blot analysis in immortalized leiomyoma cell lines demonstrated an up-regulation of NTM protein expression (2.4 AE 0.04). Treatment of leiomyoma cell lines with 17b-E 2 yielded a 1.98 AE 0.11-fold increase in NTM protein expression; however, treatment with fulvestrant showed no significant change compared with control. Leiomyoma cell lines demonstrated a 1.91 AE 0.97-fold increase in NTM protein expression after progesterone treatment. RNASeq analysis demonstrated a reduced expression in patient leiomyoma after UPA treatment (0.75 AE 0.14). Treatment of leiomyoma cells with UPA demonstrated a reduced total NTM protein amount (0.54 AE 0.31) in patients, which was confirmed with the use of IHC (UPA10 147.2 AE 9.40, UPA20 182.8 AE 8.98). In vitro studies with UPA treatment revealed a concentration-dependent effect that supported these findings. Conclusion(s): NTM, a neural cell adhesion molecule, is increased in leiomyoma compared with myometrium in patient tissue and in vitro models after estrogen and progesterone treatment. Down-regulation of expression occurs after UPA treatment, but not after fulvestrant exposure.

Neurotrimin: a novel neural cell adhesion molecule correlating with uterine fibroid phenotype

“…Uterine fibroids (UFs), also known as leiomyomas, are benign pelvic tumors that occur in nearly 70% of all reproductiveaged women (1,2). Some of these women will develop severe symptoms associated with the presence of these tumors.…”

“…Tumor growth is characterized by slow proliferation with increased deposition of extracellular matrix (proteoglycans and collagens), which participates in the fibrotic phenotype of UFs (3). This process is usually in a steroidhormone dependent manner (2). Besides steroid hormones, growth and maintenance of UFs are strongly related to growth factors, stem cells, and genetic and epigenetic abnormalities and other risk factors (1,2).…”

“…This process is usually in a steroidhormone dependent manner (2). Besides steroid hormones, growth and maintenance of UFs are strongly related to growth factors, stem cells, and genetic and epigenetic abnormalities and other risk factors (1,2).…”

“…The myometrial smooth muscles are supplied by nerves (sympathetic, parasympathetic, sensory), which run in neurovascular bundles between myometrial cells (2). Distortion of the nerves by masses of UFs leads to pelvic pain and dysmenorrhea symptoms (2). Axonal degeneration could be pathological or physiological.…”

“…The process is similar to what occurs during pregnancy, where uterine sympathetic innervation undergoes widespread degeneration, followed by reinnervation after delivery. Explanation of these findings is that estrogen acts directly on the myometrium to render it inhospitable to sympathetic axons, thus preventing the normally robust outgrowth induced by this target (2,4). Brain-derived neurotrophic factor is a neurotrophin that elicits uterine sympathetic denervation.…”