Letrozole Decreased Testosterone-Induced Cell Proliferation and Prolactin Secretion also Increased Apoptosis in MMQ and GH3 Rat Prolactinoma Cell Lines.

Aromatase enzyme plays an essential role in estrogen-induced tumorigenesis. It is expressed in the normal pituitary and more significantly in prolactinoma tissues. The aim of this study was to investigate the effects of an aromatase inhibitor, letrozole, on MMQ and GH3 rat prolactinoma cell lines and evaluate the possible mechanism of action. MMQ and GH3 cells were characterized with demonstrating aromatase enzyme and estrogen receptor alpha expression by PCR and immunofluorescence staining. After dose optimization for testosterone (T) and letrozole (L), four groups were established: only the testosteron-treated group (T) to detect cell proliferation; only letrozole-treated group (L) to investigate apoptotic effects; testosterone and letrozole concomitant-treated group to demonstrate inhibition of testosterone induced cell proliferation with letrozole treatment s(T + L) and control group (C) with no treatment. The proliferation rate of cells was determined by WST-1. For the detection of apoptotic and necrotic cells, Annexin V and caspase-3 labeling was used. Prolactin and estrogen levels were measured with ELISA, and the mRNA expression of aromatase and Esr1 was also determined. Testosterone induced the proliferation of MMQ and GH3 cells and further increased prolactin and estradiol levels. Adding letrozole to testosterone resulted in decreased cellular proliferation and even induced apoptosis. Also, letrozole administration significantly decreased prolactin and estradiol levels. However, letrozole alone had no effects on proliferation and apoptosis. Gene expression of aromatase and Esr1 was also significantly decreased by letrozole treatment. This in vitro study demonstrated that treatment of testosterone proliferating cells with letrozole resulted in decreased prolactin levels and cell proliferation and induced apoptosis, and further loss of aromatase and Esr1 mRNA expression were observed. Although this is an in vivo study, the results showed unique and novel findings which may easily be adapted to clinical use for further verification.

Evaluation of the Effect of Diclofenac Sodium and 5-Fluourasil in a 3D Cholesteatoma Cell Culture Model.

INTRODUCTION: Middle ear cholesteatoma is a benign disease with invasive and destructive clinical behaviors. It increases the rate of both chronic otitis media complications and revision surgeries. The most effective treatment of middle ear cholesteatoma is surgical excision, and there is no medical treatment for this disease. Exploring new medical treatment options may help to create treatment alternatives instead of surgery. MATERIALS AND METHODS: Required cholesteatoma tissues for cell culture were excised from 4 different participants who underwent surgery in our clinic and agreed to give tissue for the study. Cholesteatoma-derived keratinocytes and fibroblasts were cocultured in temperature-sensitive culture dishes to make a three-dimensional (3D) cholesteatoma model. Then, the effects of 1% and 2% diclofenac sodium on viability and cell proliferation rates were examined using WST-1 and annexin-V tests. RESULTS: Cell viability and proliferation rates were found to be lower and apoptosis rates were higher in the diclofenac sodium group versus the negative and positive control groups. CONCLUSION: In this present study, we described a new 3D cholesteatoma cell culture model developed using cell sheet technology and demonstrated the efficacy of diclofenac sodium on cholesteatoma for the first time in the literature. It may be used in patients with chronic otitis media with cholesteatoma, but further studies investigating ototoxic and neurotoxic effects of this molecule are needed.