Effect of irinotecan on HMGB1, MMP9 expression, cell cycle, and cell growth in breast cancer (MCF-7) cells

Abstract

Irinotecan is a natural alkaloid agent widely used in cancer therapy. High-mobility group protein B1 as a non-histone chromosomal protein plays a fundamental role in gene expression and inflammation. In this study, the effect of irinotecan on high-mobility group protein B1 and MMP9 content, gene expression, cell cycle, and cell growth in human breast cancer cells (MCF-7) was investigated. The cells were exposed to various concentrations of irinotecan and the viability determined by trypan blue exclusion and 3-(4,5-dimethylthiazal-2-yl)-2,5-diphenyltetrazolium bromide assays. Highmobility group B proteins were extracted from the control and drug-treated cells and analyzed by immunoblot. Highmobility group protein B1 and MMP9 messenger RNA expression was studied by reverse transcription polymerase chain reaction. The results demonstrated reduction of cell viability upon increasing irinotecan concentration, up-regulated highmobility group protein B1 gene expression, and down-regulated MMP9 mRNA. Although the content of high-mobility group protein B1 was decreased in chromatin extract upon drug action, no high-mobility group protein B1 release to extracellular space was detected by immunoblot analysis. Irinotecan decreased H3K9 acetylation and increased poly ADP-ribose polymerase fragmentation to 89 kDa and anion superoxide production suggesting induction of apoptosis in these cells. Propidium iodide staining of the cells 24 h after the drug treatment revealed arrest of the cells in S-phase. From the results, it is concluded that overexpression of high-mobility group protein B1 in the presence of irinotecan precedes breast cancer cells into apoptosis and in this response the binding of irinotecan to chromatin or high-mobility group protein B1 may condense/aggregate chromatin, preventing high-mobility group protein B1 release from chromatin.

High-content imaging analyses of γH2AX-foci and micronuclei in TK6 cells elucidated genotoxicity of chemicals and their clastogenic/aneugenic mode of action

“…Therefore our present results are consistent with these previous reports. Although CPT induced G2/M phase arrest in our study, S phase arrest in MCF-7 cells [48] and S phase and G2/M arrest in Caco-2 cells and CW cells have been reported [49]. In our study, GF induced M/G1 arrest, whereas G2/M phase arrest was reported in HL-60 cells [50].…”

Curcumin attenuates resistance to irinotecan via induction of apoptosis of cancer stem cells in chemoresistant colon cancer cells

“…Flow cytometry detects apoptosis via analyzing the difference of fluorescence intensity among normal cells, apoptotic cells and dead cells, it reflects apoptosis at a cellular level, while the expression of apoptosisassociated proteins detected by western blot assay reflects apoptosis at a molecular level (45,49). Secondly, 7-ethyl-10-hydroxy-camptothecin (SN-38), the metabolic product of CPT-11, induces DNA damage, and is the primary mechanism for the pharmacological effect of CPT-11 (50). Studies have reported that CPT-11 induces apoptosis of colon cancer cells through the p53 signaling pathway, and CPT-11 alone or in combination with other drugs may induce apoptosis via altering the expression of Bcl-2 family, caspase family and survival-associated genes in cancer cells (50,51).…”

In-vitro evaluation of apoptotic effect of OEO and thymol in 2D and 3D cell cultures and the study of their interaction mode with DNA

“…Induction of cell cycle arrest to prevent the cell proliferation is one of the effective ways used by cytotoxic drugs. These drugs play an anticancer role via arresting G0/G1, S or G2/M phases, thereby inhibiting cell growth, and eventually leading to apoptosis 55 , 56 . Following treatment of MDA-MB231 with various concentrations of OEO/thymol, results clearly verified that OEO/thymol has the potential to arrest MDA-MB231 cell lines at S-phase significantly.…”