A novel topoisomerase I inhibitor DIA-001 induces DNA damage mediated cell cycle arrest and apoptosis in cancer cell

Abstract

Background: DNA topoisomerase enzyme plays an essential role in controlling the DNA topology structure by binding to DNA and cutting the phosphate backbone of either one or both of the DNA strands.Here, we have identified a small molecule inhibitor, DIA-001, that directly binds to Topoisomerase 1 (Topo I) and promotes the Topo I-DNA adducts. Methods: In this study, we investigated the antitumor effects of DIA-001 using MTS assay and colony formation. We examined cell cycle of tumor cells with DIA-001 treatment in vitro by flow cytometry. And we investigated DNA damage and cell cycle marker protein after treatment with DIA-001 at different concentration and time point by western blot. Immunofluorescence was performance to detect the nuclear foci. The effects of DIA-001 on Topo I and Topo II activities were examined by DNA relaxation assays. Results: We demonstrate that DIA-001 inhibit DNA replication and arrest cell cycle progression at the G2/M phase by directly binds to Topo I and promotes the Topo I-DNA adducts. In addition, DIA-001 can activate the DNA damage response signaling cascade, resulting in apoptosis in treated cells.Conclusions: Our findings show a novel compound for treatment of cancer cells with the potential as a chemotherapy candidate that is less toxic to normal cells.

Recent advances and future directions in anti‐tumor activity of cryptotanshinone: A mechanistic review

“…The DNA topoisomerases (topos) are critical enzymes involved in modulation of breaking and rejoining of DNA strand (Liu et al, 2020). There are two characteristic types of topos including DNA topoisomerase 1 (topo1) and DNA topoisomerase 2 (topo2) that have been shown to regulate chromosomal segregation and DNA replication, recombination and repair (Alvarez‐Quilon et al, 2020; Singh, Luxami, & Paul, 2020).…”

Narciclasine, a novel topoisomerase I inhibitor, exhibited potent anti-cancer activity against cancer cells

“…DNA topoisomerases are highly specialized nuclear enzymes involved in the correction of topological DNA errors and maintaining DNA integrity, have been proved to be promising targets of antitumor drugs. In our study, topo I mediated DNA relaxation assay and topo II mediated kDNA decatenation assay in cell-free system were applied to determine the inhibitory effect of NCS on topo I and topo II [ 32 , 33 ]. As shown in Fig.…”

“…The samples were subjected to electrophoresis on a 1% agarose gel at 80 V. Then the gel was stained by EB and distained in water before being visualized under UV illuminator. CPT, a known topo I inhibitor, was served as the positive control [ 32 , 33 ]. The effect of NCS on topo II activity was determined by using a similar procedure of topo I [ 34 ].…”

Transcriptomics and Proteomics Characterizing the Anticancer Mechanisms of Natural Rebeccamycin Analog Loonamycin in Breast Cancer Cells

“…Topoisomerase I inhibitors can block the reconnection of DNA strands, lead to the accumulation of Topo I-breaking complexes, inhibit replication and transcription, and cause DNA damage, thus activating DNA damage checkpoints and inhibiting the progress of cell cycle [ 14 ]. Topoisomerase were recognized as promising targets in cancer, and various DNA Topos inhibitors have been on the market [ 15 ]. Some rebeccamycin analogues like becatecarin and edotecacin have entered clinical research.…”