Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2020 Dec 19;21(24):9715. doi: 10.3390/ijms21249715

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2020 by the authors.

Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

PMC Copyright notice

PARPi in combination with CHK1i or ATRi decreased viability more effectively than PARPi monotherapy. (A) Cell viability after treatment with PARPi (AZD2281), CHK1i (MK8776), and ATRi (AZD6738) in HR-deficient (PEO-1, BRCA2^MUT) and HR-proficient (OV-90, SKOV-3, BRCA^WT) cells at increasing concentrations for 5 days was assessed by the MTT assay. (B) Structural formulas of PARPi, ATRi, CHKi. (C,D) Colony formation assay. Colony formation was evaluated after treatment with PARPi at 0.5 µM in SKOV-3, OV-90, and PEO-1 cells. Cells (200 cells/well) were seeded into six-well plates and incubated with the indicated drug concentrations for 14 days. Colony numbers were counted manually (* p < 0.05). For each sample, the results from three replicates were averaged. PARPi and CHK1i decreased viability to 80.17% and 97.28%, respectively, compared with the control SKOV-3 cells; to 78.33% and 3.63%, respectively, in OV-90; and to 75.35% and 0.25%, respectively, in PEO-1 cells. Combination therapy with PARPi and CHK1i decreased colony formation to 68% in SKOV-3, 2.5% in OV-90, and 22.82% in PEO-1 cells. In all cell lines, drugs used in combination had a synergistic effect compared with single drug administration (SKOV-3, CDI = 0.07; OV-90, CDI = 0.07; PEO-1, CDI = 0.06). Combined PARPi and ATRi treatment decreased colony formation to <1% compared with PARPi alone and ATRi alone. In all cell lines, the combination of PARPi/ATRi had a synergistic effect compared with single compounds (SKOV-3, CDI = 0.004; OV-90, CDI = 0.03; PEO-1, CDI = 0.01). All data correspond to three biological assays and were graphed as means ± SD. (E) The morphology of SKOV-3, OV-90, and PEO-1 cells treated for 24 h with ATRi, CHK1i, and their combination with olaparib (0.5 µM concentration of each single drug) was examined under an inverted microscope (Olympus IX70, Japan) (scale bar = 100 μm). The cells were elongated and thin (blue arrows) or enlarged (red arrows). * Statistically significant changes between samples incubated with the compound compared with control cells (p < 0.05). + Statistically significant changes between samples incubated with PARPi and combination treatments (PARPi/ATRi; PARPi/CHK1i) (p < 0.05). # Statistically significant differences between samples incubated with ATRi or CHKi and their combination (PARPi/ATRi; PARPi/CHK1i) (p < 0.05).