(D) Expression of novel target protein in CD133-depelted HCC cell lines (Huh7 and Hep3B) (left panel). UBE2C genes and inhibited the expression of these proteins in HCC and the expression of UBE2C is particularly controlled by CD133 expression among those four proteins in HCC. Our results suggested that CPO may suppress stemness and malignancies in vivo and in vitro by decreasing CD133 and UBE2C expression in CD133+ HCC. Our study provides evidence that CPO could act as a novel therapeutic agent for the effective treatment of CD133+ HCC. 0.05 and ** 0.01 compared to CPO treatment group. To find previously reported biological assays related to the CPO compound, we searched the PubChem Bioassay database (Physique 1B) (National Center for Biotechnology Information. PubChemDatabase, CID = 135572401, https://pubchem.ncbi.nlm.nih.gov/compound/135572401 (accessed on Feb. 19, 2020)). Our search returned a total of nine biological assays for CPO, all of which were for numerous viruses and bacteria. It was concluded to be inactive in an inhibition assay of CDC25B-CDK2/CyclinA conversation. In addition, we searched the ChEMBL database , but the search returned no reported biological assays. Hence, we concluded that there were no reported assays for CPO related to cancer. To determine the inhibitory effects of CPO on AFP+/CD133? and AFP+/CD133+ cells, the dose-response of CPO was measured in O-Desmethyl Mebeverine acid D5 mixed HCC cell populations. Amazingly, CPO showed more sensitive effects in AFP+/CD133- cells (IC50 35.0 nM) and AFP+/CD133+ cells (IC50 37.9 nM) than in AFP?/CD133? cells (IC50 344.4 nM) (Physique 1C). Because CSCs are abundant in non-adherent spheroids of liver, colon, and breast malignancy cells, we sought to determine whether CPO alters the malignant properties of CSC populations in HCC. We treated 200 nM CPO, 10 nM taxol, 10 M cisplatin, and 10 M sorafenib under Huh7 spheroid-forming conditions and analyzed the number of spheroids created. Notably, CPO sufficiently attenuated the capacity of CD133+ HCC to form spheroids compared to taxol, cisplatin, and sorafenib (Physique 1D). To determine the effect of CPO on CD133+ HCC cells, we picked four human HCC lines that display different expression levels of CD133 in the following order: Huh7 Hep3B PLC/PRF/5 Huh6 (Physique 1E). Interestingly, when these HCC cell lines were treated with CPO, the IC50 value for CPO was inversely proportional to CD133 expression in the Huh6 (1.3 M) PLC/PRF/5 (1.2 M) Huh7 (413.8 nM) Hep3B (464.8 nM) cells (Determine 1F). In addition, a dose-response curve also offered that this cell death increased by CPO in HCC cells (Huh7, Hep3B), which contain an abundant populace of CD133+ cells compared to normal hepatocytes (Fa2N-4) (Physique 1G). Notably, immunohistochemistry O-Desmethyl Mebeverine acid D5 revealed that CPO selectively attached to the AFP+/CD133+ HCC cells in a co-culture O-Desmethyl Mebeverine acid D5 system of hepatocyte and HCC cells (Physique 1H). 2.2. CPO Induces Apoptosis in HCC Cells To confirm whether the CPO-induced inhibition of cell growth was related to an increase in apoptosis, we conducted a western blot assay and looked at the apoptosis-related parameters though V-FITC/PI circulation cytometry. We observed the early and late apoptotic phases with treatment of indicated concentrations of CPO in both cells including Huh7 and Hep3B. Significant dose-dependent increases ( 0.01) in the number of apoptotic cells following CPO Rabbit Polyclonal to TUBA3C/E treatment were only observed in Huh7 and Hep3B cells, and not Fa2N-4 cells (Physique 2A). Open in a separate window Physique 2 Apoptosis in hepatocellular carcinoma (HCC) induced by chromenopyrimidinone (CPO). (A) Annexin V/PI positive cells (apoptotic cells) in Fa2N-4, Huh7, and Hep3B cells after treatment with 200 nM O-Desmethyl Mebeverine acid D5 or 400 nM CPO for 24 h determined by circulation cytometry (left panel). Graph of percentages of apoptotic cells (right panel) detected by circulation cytometry. * 0.05 compared to untreated group. (B) Percentages of CPO stability in the media from Fa2N-4 and Huh7 cells. * 0.05 compared to control group. (C) Percentages of cell cycle phase (SubG1) after treatment with 200 nM O-Desmethyl Mebeverine acid D5 CPO for 6, 12, 24, or 48 h determined by circulation cytometry. Graph of cell phase percentages determined by circulation cytometry. (D) Expression of apoptosis-related proteins (cleaved PARP, cleaved caspase-3).