Putative mechanisms of antitumor activity of cyano-substituted heteroaryles in HeLa cells

Abstract

Six recently synthesized cyano-substituted heteroaryles, which do not bind to DNA but are highly cytotoxic against the human tumor cell line HeLa, were analyzed for their antitumor mechanisms of action (MOA). They did not interfere with the expression of human papillomavirus oncogenes integrated in the HeLa cell genome, but they did induce strong G1 arrest and result in the activation of caspase-3 and apoptosis. A computational analysis was performed that compared the antiproliferative activities of our compounds in 13 different tumor cell lines with those of compounds listed in the National Cancer Institute database. The results indicate that interference with cytoskeletal function and inhibition of mitosis are the likely antitumor MOA. Furthermore, a second in silico investigation revealed that the tumor cells that are sensitive to the cyano-substituted compounds show differences in their expression of locomotion genes compared with that of insensitive cell lines, thus corroborating the involvement of the cytoskeleton. This MOA was also confirmed experimentally: the cyano-substituted heteroaryles disrupted the actin and the tubulin networks in HeLa cells and inhibited cellular migration. However, further analysis indicated that multiple MOA may exist that depend on the position of the cyano-group; while cyano-substituted naphthiophene reduced the expression of cytoskeletal proteins, cyano-substituted thieno-thiophene-carboxanilide inhibited the formation of cellular reactive oxygen species.

REVIGO Summarizes and Visualizes Long Lists of Gene Ontology Terms

“…Contrary to the ‘toy example’ described above, these examples contain data a researcher would encounter in a real-life situation: very long, unintelligible lists of GO terms. The data sets cover diverse areas of the life sciences: example #1, a comparative analysis of predicted gene expression levels in bacteria and archaea [15] ; example #2, finding putative targets for the cytostatic activity of a small molecule against cancer cell lines [16] ; and example #3, gene expression profiling of aggressive breast cancer samples [17] . Data from the example #3 was used to generate the visualizations in Figs.…”

“…Very recently, software called RedundancyMiner (RM) has been made available [16] that has similar aims as REVIGO – to mitigate the issue of redundancy in lists of GO terms. While it is difficult to quantitatively benchmark and compare programs dealing with subjective categories such as interpretability of a list of GO terms, or the utility of a visualization method in leading to novel insight, we here provide a comparison the features of the two packages.…”

Accurate Models for P-gp Drug Recognition Induced from a Cancer Cell Line Cytotoxicity Screen

“…After 24 h, cells were treated with indicated compounds and concentrations, where the highest DMSO concentration was at <1%. Following a 72 h incubation, an MTT assay (Sigma) was performed per standard protocol (e.g., see Supek et al 76 and Ester et al 77 ). The absorbance (A) of the microtiter plate was measured on a microplate reader at 570 nm where absorbance is directly proportional to the number of living, metabolically active cells.…”

“…Results were analyzed according to a slightly modified protocol used at the NCI-DTP (http://dtp.nci.nih.gov/branches/btb/ivclsp.html) as previously described. 76,77 Briefly, a positive percentage of growth (PG) indicates cell growth following drug treatment, where percent growth is relative to a negative control (no drug). A PG of 100% shows that the treated culture grew as well as the negative control, and 0% means growth has stopped upon adding the drug.…”