ABSTRACT
Aberrant activation of the phosphatidylinositol 3-kinase(PI3K)-protein kinase B(PKB,Akt)-mammalian target of rapamycin(mTOR) pathway is commonly observed in human cancer and is critical for cell survival, proliferation and differentiation.A variety of small molecule inhibitors targeting PI3K-Akt-mTOR pathway are under clinical studies.This review will summarize the recent studies in terms of the PI3K-Akt-mTOR signaling pathway and cancer,research progress of the antitumor activity possessed by PI3K-Akt-mTOR inhibitors,as well as the recent research in the related field conducted by our group.
ABSTRACT
<p><b>OBJECTIVE</b>To identify a HEK293 cell line containing stably-transfected H3R gene, and to screen the novel non-imidazole compounds with H3R antagonist activity.</p><p><b>METHODS</b>The expression of rat H3 receptor in cell line was detected by RT-PCR and Western blot. An elevation of intercellular cAMP concentration induced by forskolin was measured as the index for screening compounds with H3R antagonist activity.</p><p><b>RESULTS</b>The H3R-transfected HEK-293 cells stably expressed high level of rat H3 receptor mRNA and protein. Forskolin significantly increased intercellular cAMP concentration in the H3R-transfected HEK-293 cells. H3R agonist (R)-α-methylhistamine inhibited the forskolin-induced production of intercellular cAMP. H3R antagonist thioperamide and newly synthesized non-imidazole compounds XHA23 and XHA25 blocked (R)-α- methylhistamine reversal of forskolin-induced cAMP formation in a concentration-dependent manner, and the IC50 values were 3.62 μmol/L, 0.49 μmol/L, 0.14 μmol/L, respectively.</p><p><b>CONCLUSION</b>The H3R-transfected HEK293 cells stably express high level of rat H3 receptor, and can be used for screening compounds with H3R antagonist activity. The non-imidazole compounds XHA23 and XHA25 may have H3R antagonist activity.</p>