New Selective Progesterone Receptor Modulators and Their Impact on the RANK/RANKL Complex Activity
MOLECULES
Authors: Blaszczak-Swiatkiewicz, Katarzyna
Abstract
Breast cancer depends on women's age. Its chemotherapy and hormone therapy lead to the loss of bone density and disruption of the skeleton. The proteins RANK and RANKL play a pivotal role in the formation of osteoclasts. It is also well established that the same proteins (RANK and RANKL) are the main molecules that play an important role in mammary stem cell biology. Mammary stem cells guarantee differentiation of the epithelial mammary cells, the growth of which is regulated by the progesterone-induced RANKL signaling pathway. The crosstalk between progesterone receptor, stimulated by progesterone and its analogues results in RANKL to RANK binding and activation of cell proliferation and subsequently unlimited expansion of the breast cancer cells. Therefore downstream regulation of this signaling pathway is desirable. To meet this need, a new class of selective estrogen receptor modulators (SPRMs) with anti- and mesoprogestin function were tested as potential anti-RANK agents. To establish the new feature of SPRMs, the impact of tested SPRMs on RANK-RANKL proteins interaction was tested. Furthermore, the cells proliferation upon RANKL stimulation, as well as NFkB and cyclin D1 expression, induced by tested SPRMs were analyzed. Conducted experiments proved NFkB expression inhibition as well as cyclin D1 expression limitation under asoprisnil and ulipristal treatment. The established paracrine anti-proliferative activity of antiprogestins together with competitive interaction with RANK make this class of compounds attractive for further study in order to deliver more evidence of their anti-RANK activity and potential application in the breast cancer therapy together with its accompanied osteoporosis.
Traf6 inhibitor boosts antitumor immunity by impeding regulatory T cell migration in Hepa1-6 tumor model
INTERNATIONAL IMMUNOPHARMACOLOGY
Authors: Wu, Xiao; Xue, Rong; Peng, Hao; Gan, Xiaojie; Lu, Xu; Yan, Wei; Tian, Yizhu; Ni, Xuhao; Shen, Hongbin; Cheng, Feng; Wang, Xuehao; Wang, Xiaoming; Lu, Ling
Abstract
Tumors escape immune attacks via various mechanisms, among which activation of regulatory pathways in effector immune cells and recruitment of immunosuppressive cells are usually employed. Traf6 is a member of the family of tumor necrosis factor receptor-associated factors and involved in many signaling pathways. While it plays important roles in both tumor biology and immune system, the potential therapeutic role of Traf6 in tumor immunotherapy hasn't ever been assessed. Here, we confirmed the anti-tumor effect of Traf6 inhibitor in Hepa1-6 tumor model. Flow cytometry-based analysis revealed that T cell-mediated antitumor immunity was provoked and the infiltration of Treg cells was restrained when treated with Traf6 inhibitor. Via an in vivo migration assay, we found that Traf6 inhibitor decreased the population of intratumor Tregs by impeding the migration of Tregs towards tumor. Finally, we demonstrated that combination of Traf6 inhibitor and PD-1 blockade could receive a better antitumor efficiency. These results implicated that Traf6 inhibitor could serve as a supplement for immune checkpoint therapy.