Two Novel Precursors of the HIV-1 Protease Inhibitor Darunavir Target the UPR/Proteasome System in Human Hepatocellular Carcinoma Cell Line HepG2

Abstract

Background: Several pre-clinical and clinical reports suggest that HIV-1 protease inhibitors, in addition to the antiretroviral properties, possess pleiotropic pharmacological effects including anticancer action. Therefore, we investigated the pro-apoptotic activity in tumor cells of two molecules, RDD-19 and RDD-142, which are hydroxyethylamine derivatives’ precursors of darunavir and several HIV-1 protease inhibitors. Methods: Three hepatoma cell lines and one non-pathological cell line were treated with RDD-19 and RDD-142, and cell viability was assessed. The expression levels of several markers for ER stress, autophagy, cellular ubiquitination, and Akt activation were quantified in HepG2 cells treated with RDD-19 and RDD-142 to evaluate apoptotic and non-apoptotic cell death. Results: RDD-19 and RDD-142 showed a greater dose-dependent cytotoxicity towards the hepatic tumor cell line HepG2 compared to the non-pathological hepatic cell line IHH. Both molecules caused two types of cell death, a caspase-dependent apoptosis, which was ascertained by a series of biochemical and morphological assays, and a caspase-independent death that was characterized by the induction of ER stress and autophagy. The strong increase of ubiquitinated proteins inside the cells suggested that the target of these molecules could be the proteasome and in silico molecular docking analysis that was used to support the plausibility of this hypothesis. Furthermore, cells treated with the two compounds displayed decreased levels of p-AKT, which interferes with cell survival and proliferation. Conclusions: These findings demonstrate that two compounds, RDD-19 and RDD-142, have pleiotropic effects and that they may represent promising anticancer candidates.

Novel Wild Type and Mutate HIV-1 Protease Inhibitors Containing Heteroaryl Carboxamides in P2: Synthesis, Biological and ADME Evaluations

“…Easily synthesized benzothienyl-, benzofuryl-and indolyl derivatives bearing either a carboxyamide or a carbamoyl spacer in general showed high in vitro activity against native protease. They also confirmed their inhibition activity in mammalian cells, showing a general low citotoxicity and great metabolic stability, thus demonstrating their promising potential [17][18][19][20].…”

“…CH2Cl2 was dried by distillation over anhydrous CaCl2 in an inert atmosphere. Dry THF and DMF were commercially available, All 1 H and 13 C NMR spectra for the following compounds were consistent to literature data: (1R,2S)-(1-Benzyl-2-hydroxy-3-iso-butylamino-propyl)-carbamic acid tert-butyl ester (2) [17], (1S,2R)-[1-Benzyl-2-hydroxy-3-iso-butyl-(4-methoxy-benzenesulfonyl)amino-propyl]-carbamic acid tertbutyl ester (3a) [18], (1S,2R)-[1-Benzyl-2-hydroxy-3-iso-butyl-(4-nitro-benzenesulfonyl)aminopropyl]-carbamic acid tert-butyl ester (3b) [21], (2R,3S)-N-(3-Amino-2-hydroxy-4-phenyl-butyl)-Nisobutyl-4-methoxy-benzenesulfonamide (4a) [18], (2R,3S)-N-(3-Amino-2-hydroxy-4-phenyl-butyl)-N-isobutyl-4-nitro-benzenesulfonamide (4b) [20].…”

“…The epoxide was firstly opened with iso-butyl amine to afford the monoprotected diaminoalcohol 2, 4-OMe-and 4-NO2-phenylsulfonyl moieties were alternatively introduced on secondary amine, affording 3a and 3b, respectively. N-Boc group was then efficiently displaced by TFA and the crude ammonium trifluoroacetate derivatives were treated with Et3N, affording the free amines 4a-b [18,20].…”

PEGylated Liposomes Loaded with Carbamate Inhibitor ANP0903 Trigger Apoptosis by Enhancing ER Stress in HepG2 Cancer Cells

“…Literature data report that several HIV-PIs and their analogs have anticancer activity via induction of ER stress (ERS) and autophagy [16][17][18][19]. Therefore, in this study, it was verified whether the exposure of HepG2 cells to ANP0903 PEG-liposomes, which showed to be more effective, triggered unfolded protein response (UPR) and autophagy mechanisms.…”