Glucocorticoid metabolism at the tissue level is regulated by two isoenzymes 11β-hydroxysteroid dehydrogenase (11β-HSD), which mutually convert biologically active cortisol and inactive cortisone. Recent research is focused on the role of 11β-HSD1 and 11β-HSD2 as autocrine factors of tumor cell proliferation and differentiation. Herein, we report the synthesis of novel 2-(isopropylamino)thiazol-4(5H)-one derivatives and their inhibitory activity for 11β-HSD1 and 11β-HSD2. The derivative containing the spiro system of thiazole and cyclohexane rings shows the highest degree of 11β-HSD1 inhibition (54.53% at 10 µM) and is the most selective inhibitor of this enzyme among the tested compounds. In turn, derivatives containing ethyl and n-propyl group at C-5 of thiazole ring inhibit the activity of 11β-HSD2 to a high degree (47.08 and 54.59% at 10 µM respectively) and are completely selective. Inhibition of the activity of these enzymes may have a significant impact on the process of formation and course of tumors. Therefore, these compounds can be considered as potential pharmaceuticals supporting anti-cancer therapy.

Uterine myomas represent one of the most frequently manifested benign tumors in women. They originate from smooth muscle cells of myometrium or its blood vessels. Many studies suggest that inflammation and pro-inflammatory factors may play a role in the carcinogenesis with an involvement of the transcription factor NF-kB which activity can be controlled by various environmental factors, including many cytokines. The aim of the study was to investigate the expression of NF-B, interleukin-1b (IL-1b), tumor necrosis factor a (TNF-a), cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS) in myometrium and uterine myomas of women of various age. The expression of NF-kB, selected cytokines and enzymes was estimated in women of reproductive or perimenopausal age by semiquantitative immunohistochemistry. The expression of the examined proteins was higher in myomas than in control myometrium and was dependent on the size of myomas and the age of women. However, the expression of the cytoplasmic NF-kB observed in uterine myomas was independent on the size of myomas and no significant differences were observed in the number of stained nuclei between control and myoma groups. Thus, the expression of proinflammatory factors in myomas was not accompanied by the nuclear activation of NF-kB p65. The results of our study indicate that the examined factors may be involved in the pathogenesis of benign tumors and not only malignant diseases.

Tumors are currently more and more common all over the world; hence, attempts are being made to explain the biochemical processes underlying their development. The search for new therapeutic pathways, with particular emphasis on enzymatic activity and its modulation regulating the level of glucocorticosteroids, may contribute to the development and implementation of new therapeutic options in the treatment process. Our research focuses on understanding the role of 11β-HSD1 and 11β-HSD2 as factors involved in the differentiation and proliferation of neoplastic cells. In this work, we obtained the 9 novel N-tert-butyl substituted 2-aminothiazol-4(5H)-one (pseudothiohydantoin) derivatives, differing in the substituents at C-5 of the thiazole ring. The inhibitory activity and selectivity of the obtained derivatives in relation to two isoforms of 11β-HSD were evaluated. The highest inhibitory activity for 11β-HSD1 showed compound 3h, containing the cyclohexane substituent at the 5-position of the thiazole ring in the spiro system (82.5% at a conc. 10 µM). On the other hand, the derivative 3f with the phenyl substituent at C-5 showed the highest inhibition of 11β-HSD2 (53.57% at a conc. of 10 µM). A low selectivity in the inhibition of 11β-HSD2 was observed but, unlike 18β-glycyrrhetinic acid, these compounds were found to inhibit the activity of 11β-HSD2 to a greater extent than 11β-HSD1, which makes them attractive for further research on their anti-cancer activity.