2­D08 mediates notable anticancer effects through multiple cellular pathways in uterine leiomyosarcoma cells.

2',3',4'­trihydroxyflavone (2­D08), a SUMO E2 inhibitor, has several biological functions, including anticancer activity, but its effects on uterine leiomyosarcoma (Ut­LMS) are unknown. The anticancer activity of 2­D08 was explored in an in vitro model using SK­LMS­1 and SK­UT­1B cells (human Ut­LMS cells). Treatment with 2­D08 inhibited cell viability in a dose­ and time­dependent manner and significantly inhibited the colony­forming ability of Ut­LMS cells. In SK­UT­1B cells treated with 2­D08, flow cytometric analysis revealed a slight increase in apoptotic rates, while cell cycle progression remained unaffected. Western blotting revealed elevated levels of RIP1, indicating induction of necrosis, but LC3B levels remained unchanged, suggesting no effect on autophagy. A lactate dehydrogenase (LDH) assay confirmed increased LDH release, further supporting the induction of apoptosis and necrosis by 2­D08 in SK­UT­1B cells. 2­D08­induced production of reactive oxygen species and apoptosis progression were observed in SK­LMS­1 cells. Using Ki67 staining and bromodeoxyuridine assays, it was found that 2­D08 suppressed proliferation in SK­LMS­1 cells, while treatment for 48 h led to cell­cycle arrest. 2­D08 upregulated p21 protein expression in SK­LMS­1 cells and promoted apoptosis through caspase­3. Evaluation of α­SM­actin, calponin 1 and TAGLN expression indicated that 2­D08 did not directly initiate smooth muscle phenotypic switching in SK­LMS­1 cells. Transcriptome analysis on 2­D08­treated SK­LMS­1 cells identified significant differences in gene expression and suggested that 2­D08 modulates cell­cycle­ and apoptosis­related pathways. The analysis identified several differentially expressed genes and significant enrichment for biological processes related to DNA replication and molecular functions associated with the apoptotic process. It was concluded that 2­D08 exerts antitumor effects in Ut­LMS cells by modulating multiple signaling pathways and that 2­D08 may be a promising candidate for the treatment of human Ut­LMS. The present study expanded and developed knowledge regarding Ut­LMS management and indicated that 2­D08 represents a notable finding in the exploration of fresh treatment options for such cancerous tumors.

2-D08 treatment regulates C2C12 myoblast proliferation and differentiation via the Erk1/2 and proteasome signaling pathways.

SUMOylation is one of the post-translational modifications that involves the covalent attachment of the small ubiquitin-like modifier (SUMO) to the substrate. SUMOylation regulates multiple biological processes, including myoblast proliferation, differentiation, and apoptosis. 2-D08 is a synthetically available flavone, which acts as a potent cell-permeable SUMOylation inhibitor. Its mechanism of action involves preventing the transfer of SUMO from the E2 thioester to the substrate without influencing SUMO-activating enzyme E1 (SAE-1/2) or E2 Ubc9-SUMO thioester formation. However, both the effects and mechanisms of 2-D08 on C2C12 myoblast cells remain unclear. In the present study, we found that treatment with 2-D08 inhibits C2C12 cell proliferation and differentiation. We confirmed that 2-D08 significantly hampers the viability of C2C12 cells. Additionally, it inhibited myogenic differentiation, decreasing myosin heavy chain (MHC), MyoD, and myogenin expression. Furthermore, we confirmed that 2-D08-mediated anti-myogenic effects impair myoblast differentiation and myotube formation, reducing the number of MHC-positive C2C12 cells. In addition, we found that 2-D08 induces the activation of ErK1/2 and the degradation of MyoD and myogenin in C2C12 cells. Taken together, these results indicated that 2-D08 treatment results in the deregulated proliferation and differentiation of myoblasts. However, further research is needed to investigate the long-term effects of 2-D08 on skeletal muscles.

Effects of genistein on anti-tumor activity of cisplatin in human cervical cancer cell lines.

OBJECTIVE: To investigate the effect of genistein on the anticancer effects of chemotherapeutic agents, we examined the effect of a genistein and cisplatin combination on CaSki human cervical cancer cells. METHODS: After the cervical cancer cells (HeLa cells, CaSki cells) had been cultured, cisplatin and genistein were added to the culture medium, and the cell activity was measured using MTT assay. The CaSki cells were cultured in a medium containing cisplatin and genistein, and then, the cells were collected in order to measure p53, Bcl2, ERK, and caspase 3 levels by western blotting. RESULTS: Both the HeLa and CaSki cells had decreased cell viabilities when the cisplatin concentration was 10 µM or higher. When combined with genistein, the cell viabilities of the HeLa and CaSki cells decreased at cisplatin concentrations of 8 µM and 6 µM, respectively. The administration of genistein increased the toxicity of cisplatin in the HeLa and CaSki cells. In the CaSki cells, the p-ERK1/2 level decreased by 37%, the p53 expression level increased by 304%, and the cleaved caspase 3 level increased by 115% in the cisplatin+genistein group compared to that in the cisplatin group. Bcl2 expression was reduced by 69% in the cisplatin+genistein group compared to that in the cisplatin group. CONCLUSION: Genistein enhances the anticancer effect of cisplatin in CaSki cells, and can be used as a chemotherapeutic adjuvant to increase the activity of a chemotherapeutic agent.

Effect of quercetin on the anti-tumor activity of cisplatin in EMT6 breast tumor-bearing mice.

OBJECTIVE: The purpose of this study was to determine the effect of quercetin on the antitumor activity of cisplatin and its side-effects. METHODS: EMT6 cells, a mouse breast cancer cell line, were injected subcutaneously in mice to generate a breast tumor-bearing mouse model. Experimental groups were divided into four groups: control (C), quercetin (Q), cisplatin (CP), and cisplatin+quercetin (CP+Q). RESULTS: The tumor volume of the CP+Q group was significantly lower than that of the CP group. Serum blood urea nitrogen and creatinine levels in the CP+Q group were lower than those in the CP group. Renal γ-glutamyltranspeptidase and alkaline phosphatase activities were significantly higher in the CP+Q group than in the CP group, and the content of renal thiobarbituric acid reactive substance was significantly lower in the CP+Q group than that in the CP group. These results suggested that quercetin and cisplatin synergistically increased cellular toxicity in breast cancer cells and mediated cancer growth inhibition, thereby enhancing the antitumor effect of cisplatin compared to when only cisplatin was administered. Quercetin also reduced renal toxicity, which arose as a potential a side effect of cisplatin. CONCLUSION: The enhanced antitumor effect of cisplatin and decreased renal toxicity after quercetin treatment suggested the applicability of quercetin as an adjuvant for chemotherapeutic agents.