RESUMO
The abnormality of ubiquitin proteasome pathway is an important factor leading to the imbalance of protein homeostasis. In this process, the deubiquitinase responsible for removing the ubiquitin chain of protein substrate is very important. Its abnormal activity or expression can cause the functional changes of key oncogenic/tumor suppressor proteins, which directly or indirectly lead to the occurrence, development and malignant evolution of tumors. Based on this, the discovery and research of small molecule inhibitors targeting deubiquitinases have become a hot field of anti-tumor candidate drugs. This review will focus on the regulatory effect and mechanism of ubiquitin proteasome pathway, especially deubiquitinase on tumor, introduce the application of deubiquitinase small molecule inhibitors in tumor treatment, and discuss the research status and latest progress of small molecule inhibitors, so as to provide ideas for the research of new anti-tumor strategies based on deubiquitinase.
RESUMO
<p><b>OBJECTIVE</b>To establish a method for screening cysteinyl leukotriene receptor 2 (CysLT(2)) antagonists and to preliminarily screen a series of synthetic compounds.</p><p><b>METHODS</b>Rat glioma cell line (C6 cells) highly expressing CysLT(2) receptor was used. Intracellular calcium concentration was measured after stimulation with the agonist LTD(4),which was used to screen compounds with antagonist activity for CysLT(2) receptor. Bay u9773, a CysLT1/CysLT(2) receptor non-selective antagonist, and AP-100984, a CysLT(2) receptor antagonist, were used as control.</p><p><b>RESULT</b>PT-PCR showed a higher expression of CysLT(2) receptor in C6 cells. LTD(4) at 1 mumol/L significantly increased intracellular calcium in C6 cells; the maximal effect was about 37.5% of ATP, a positive stimulus.LTD(4)-induced increase of intracellular calcium was blocked by CysLT(2) receptor antagonists, but not by CysLT(1) receptor antagonists. Among the synthetic compounds, D(XW-)1,2,13,23,29 and 30 inhibited LTD(4)-induced increase of intracellular calcium.</p><p><b>CONCLUSION</b>LTD(4)-induced change in intracellular calcium in C6 cells can be used as a screening method for CysLT(2) receptor antagonists. The compounds, D(XW-)1,2,13,23,29 and 30, possess antagonist activity for CysLT(2) receptor.</p>