4-Sulfonamide substituted benzamidobenzimidazolones were designed and docked into the active site model of CDK2, using an oxindole inhibitor as the template. Compounds 6a-6i were then prepared from the reaction of the sulfonyl chloride 1 with different amines to give the corresponding acids (2a-2i), which were converted to their corresponding acyl chlorides (3a-3i). Reaction of 3a-3i with o-nitrophenylhydrazine afforded the respective nitro derivatives (4a-4i). The nitro groups were then reduced to give the corresponding amines (5a-5i), which, upon reaction with ethyl chloroformate, the target compounds (6a-6i) were produced. Target benzimidazolone derivatives (9a-9e) were also prepared from the reaction of isopropenyl benzimidazolone (8) with different sulfonyl or acyl chlorides. The target compounds were then tested by a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against the cancer cell lines, Hep G2, HT-29, CL1-5 and AGS. Despite similar binding properties of the flexible benzamidobenzimidazolones and rigid cytotoxic oxindole inhibitors at the active site of CDK2, biological screening results indicated that benzamidobenzimidazolones did not exhibit significant cell growth inhibition in vitro. Their analogue, 3-acyl benzimidazolone (12), however, revealed cytotoxicity similar to that of the reference oxindole inhibitor.

Objective: This study aimed to explore biological function of long intergenic non-protein coding RNA 265 (LINC00265) in hepatocellular carcinoma (HCC) cells, and evaluate its potential function as a biomarker. Materials and Methods: In this experimental study, GEPIA database and Kaplan-Meier Plotter database were employed to analyze LINC00265 expression in HCC tissue samples and its predicting value for prognosis. LINC00265 expression in HCC tissues and cells was detected by quantitative real-time polymerase chain reaction (qRT-PCR). After overexpressing and knocking-down of LINC00265 in HCC cells, cell counting kit-8 (CCK-8) and 5-Ethynyl-2’ deoxyuridine (EdU) assays were adopted to detect proliferation of HCC cells. Transwell assay was used to detect migration and invasion of HCC cells. Interaction of LINC00265 with E2F transcription factor 1 (E2F1) was verified by the catRAPID online analysis tool, RNA pull-down experiment and RNA binding protein immunoprecipitation (RIP) assay. Binding of E2F1 to the promoter region of cyclin-dependent kinases 2 (CDK2) was detected by dual-luciferase reporter assay and chromatin immunoprecipitation. Regulatory effects of LINC00265 and E2F1 on CDK2 expression were probed by Western blot. Results: LINC00265 expression was increased in HCC tissues and cells. LINC00265 overexpression promoted proliferation, migration and invasion of HCC cells, and knocking-down LINC00265 worked oppositely. LINC00265 could bind to E2F1 and it could enhance combination of E2F1 and CDK2 promoter regions, thus promoting CDK2 transcription. LINC00265 overexpression promoted expression of CDK2 in HCC cells. Conclusion: Our data suggested that LINC00265 can promote malignant behaviors of HCC cells by recruiting E2F1 to the promoter region of CDK2.

Several cycline dependent kinase 2 (CDK2) inhibitors with different chemical structures have been introduced. The hinge region of CDK2 (residues 81–84) contains a set of hydrogen bond donor and acceptor sites some of which must be satisfied for potent inhibitor binding. The benzimidazolone skeleton may provide such interactions. Accordingly, 3-sulfonamide substituted benzamido-benzimidazolones 24-31 were prepared starting from benzoic acid to give the acyl chloride 1 which was reacted with different amines to afford the acids 2-9. The acids were changed to their corresponding acyl chlorides 10-17. Reaction of 10-17 with o-nitropheyl hydrazine gave the nitro derivatives 18-25 followed by reduction of the nitro groups to give 26-33 which were then reacted with ethyl chloroformate to give the target compounds 34-41. The 3-pyridyl derivative 47 was prepared starting with chlorosulfonyl benzoyl chloride to give the acid 43 which was changed to the corresponding acyl, nitro and amino derivatives 44, 45 and 46, respectively, followed by the final ring closure reaction to give 47. The dibenzimidazolinoe derivative 49 was also obtained from the reaction of isopropenyl-benzimidazolone 48 and 3-chloro sulfonyl benzoyl chloride. The target compounds were then tested against the cancer cell lines, Hepa G2, HT-29, CL1-5 and AGS. Results indicated that the target compounds did not show reasonable cell growth inhibition comparing to the positive and negative controls.