Cervical cancer poses a significant threat to women’s health, and its metastasis is one of the leading causes of cancer-related deaths. Tubeimoside I (TBMS1) is a traditional Chinese medicinal herb with anticancer properties. We previously demonstrated the anticancer effect of TBMS1 in cervical cancer by inducing autophagy-related cell death. Nevertheless, whether and how TBMS1 prevents cervical cancer metastasis remain unclear. Wound healing, transwell assays, and a lung metastasis mouse model were used to evaluate cell metastasis. Immunoprecipitation combined with site-directed mutagenesis was used to explore ubiquitination modifications and ubiquitinated sites of histone deacetylase 5 (HDAC5). HDAC5 depletion and RNA-seq analysis were conducted to investigate the anti-metastatic mechanism of TBMS1. We show that low dose of TBMS1 inhibits cervical cancer metastasis. Mechanistically, TBMS1 binds to HDAC5 and prevents HDAC5 ubiquitination at lysine 137 and 538, leading to a decrease in proteasomal degradation of HDAC5. TBMS1-mediated HDAC5 upregulation further reduces the acetylation level of histone H3 lysine 27 (H3K27ac) and suppresses KPNA2 expression. HDAC5 depletion significantly attenuates TBMS1’s anti-metastatic effect in cervical cancer. Our study reveals HDAC5/H3K27ac/KPNA2 axis as the anti-metastatic mechanism of TBMS1 in cervical cancer, suggesting TBMS1 serves as a promising drug for cervical cancer treatment.
Hepatocellular carcinoma (HCC) is a global public health problem with increased morbidity and mortality. Agrimol B, a natural polyphenol, has been proved to be a potential anticancer drug. Our recent report showed a favorable anticancer effect of agrimol B in HCC, however, the mechanism of action remains unclear. Here, we found agrimol B inhibits the growth and proliferation of HCC cells in vitro as well as in an HCC patient-derived xenograft (PDX) model. Notably, agrimol B drives autophagy initiation and blocks autophagosome-lysosome fusion, resulting in autophagosome accumulation and autophagy arrest in HCC cells. Mechanistically, agrimol B downregulates the protein level of NADH:ubiquinone oxidoreductase core subunit S1 (NDUFS1) through caspase 3-mediated degradation, leading to mitochondrial reactive oxygen species (mROS) accumulation and autophagy arrest. NDUFS1 overexpression partially restores mROS overproduction, autophagosome accumulation, and growth inhibition induced by agrimol B, suggesting a cytotoxic role of agrimol B-induced autophagy arrest in HCC cells. Notably, agrimol B significantly enhances the sensitivity of HCC cells to sorafenib in vitro and in vivo. In conclusion, our study uncovers the anticancer mechanism of agrimol B in HCC involving the regulation of oxidative stress and autophagy, and suggests agrimol B as a potential therapeutic drug for HCC treatment.
BACKGROUND:Runt-related transcription factor-1 (RUNX1), a key member of the core-binding factor family of transcription factors, has emerged as a novel therapeutic target for cardiovascular disease. There is an urgent need to fully understand the expression pattern of Runx1 in the heart and the mechanisms by which it is controlled under normal conditions and in response to disease. The expression of Runx1 is regulated at the transcriptional level by two promoters designated P1 and P2. Alternative usage of these two promoters creates differential mRNA transcripts diversified in distribution and translational potential. While the significance of P1/P2 promoter-switch in the transcriptional control of Runx1 has been highlighted in the embryogenic process, very little is known about the level of P1- and P2-specific transcripts in adult hearts, and the underlying mechanisms controlling the promoter-switch.METHODS:To amplify P1/P2 specific sequences in the heart, we used two different sense primers complementary to either P1 or P2 5'-regions to monitor the expression of P1/P2 transcripts. DNA methylation levels were assessed at the Runx1 promoter regions. Rats were grouped by age.RESULTS:The expression levels of both P1- and P2-derived Runx1 transcripts were decreased in older rats when compared with that in young adults, paralleled with an age-dependent decline in Runx1 protein level. Furthermore, older rats demonstrated a higher degree of DNA methylation at Runx1 promoter regions. Alternative promoter usage was observed in hearts with increased age, as reflected by altered P1:P2 mRNA ratio.CONCLUSION:Our data demonstrate that the expression of Runx1 in the heart is age-dependent and underscore the importance of gene methylation in the promoter-mediated transcriptional control of Runx1, thereby providing new insights to the role of epigenetic regulation in the heart.
Cerulenin is a fungal metabolite and a specific inhibitor of fatty acid synthase (FASN), which has shown a potential anticancer activity. 20-25% of breast cancer patients with ErbB2-overexpressing develop resistance to treatment. Therefore, it is urgent to find an effective new target for the treatment of ErbB2-overexpressing breast cancer. Our previous study found that cerulenin inhibits the glycolysis and migration of SK-BR-3 cells, but the effect of cerulenin on other malignant phenotypes of breast cancer is still unknown. Furthermore, the mechanism by which cerulenin displays its inhibitory effects is not fully understood. In this study, we systematically investigate the inhibitory effects of cerulenin on proliferation, migration, invasion and glycolysis of ErbB2-overexpressing breast cancer cells and its molecular mechanism. We found that cerulenin obviously suppresses the proliferation, migration, invasion as well as glycolysis. Through bioinformatic analyses, we found that PKM2 might be a target of cerulenin. In addition, ErbB2 and its signaling pathway upregulated PKM2 protein levels. Furthermore, we demonstrated that cerulenin downregulated the protein levels of ErbB2, PKM2 and EMT markers (MMP9, MMP2 and Snail2) in a dose- and time-dependent manner. Finally, the inhibitory of cerulenin on colony formation, migration, invasion and glycolysis, as well as protein levels of EMT markers were rescued by replenishing with PKM2. These findings illustrated that cerulenin inhibits proliferation, migration, invasion and glycolysis by targeting ErbB2/PKM2 pathway in ErbB2-overexpressing breast cancer cells.
ErbB2 is overexpressed in approximately 25% of breast cancer cases and promotes metastatic potential. We previously reported that ErbB2 promoted glycolysis via heat shock factor 1 (HSF1)/lactate dehydrogenase A (LDHA) axis and ErbB2-mediated glycolysis was required for the growth of breast cancer cells. However, the importance of HSF1/LDHA axis-mediated glycolysis in ErbB2-enhanced metastatic potential remains to be elucidated. In this study, we investigated the effect of HSF1/LDHA axis-mediated glycolysis on migration and invasion in breast cancer cells. Firstly, we demonstrated that ErbB2-mediated migration and invasion were dependent on glycolysis in breast cancer cells. Secondly, we found that HSF1/LDHA axis played an important role in glycolysis, which contributed to ErbB2-enhanced migration and invasion. Finally, we showed that ErbB2 was positively correlated with HSF1/LDHA axis in invasive breast cancer patients via GEO analysis. Taken together, ErbB2 promoted metastatic potential of breast cancer cells via HSF1/LDHA axis-mediated glycolysis. And our findings indicated that targeting HSF1/LDHA axis may be a promising strategy to treat ErbB2-overexpressing breast cancer patients.
The incidence of breast cancer ranks at the top of female malignant tumors in China. Metastasis remains the main cause of death among breast cancer patients. The overexpression of ErbB2 is closely related to the metastasis and poor prognosis of breast cancer patients. Therefore, ErbB2 is an important clinical therapeutic target of breast cancer. However, the molecular mechanism of ErbB2 promoting breast cancer metastasis has not been studied clearly. Stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in catalyzing the conversion of saturated fatty acids (SFAs) into monounsaturated fatty acids (MUFAs). SCD1 is overexpressed in breast cancer, and its overexpression is an indicator of poor prognosis in breast cancer patients. However, the role of SCD1 in ErbB2-overexpressing breast cancer metastasis has not been reported. In this study, we investigated the role of SCD1 in the migration and invasion of ErbB2-overexpressing breast cancer cells and its molecular mechanism. First, we demonstrated that ErbB2 upregulates the expression of SCD1. Second, we found that SCD1 and its catalytic product oleic acid played crucial roles in migration and invasion of ErbB2-overexpressing breast cancer cells. Finally, we found that in breast cancer cells, ErbB2 upregulated SCD1 through lactate dehydrogenase A (LDHA). To sum up, upregulation of SCD1 by ErbB2 via LDHA promotes the migration and invasion of breast cancer cells.
目的 在体外研究小干扰RNA(siRNA)沉默己糖激酶2(HK2)对人乳腺癌SK-BR-3细胞增殖、迁移和侵袭的影响及其分子机制.方法 在SK-BR-3细胞中分别转染siRNA阴性、siHK2-A和siHK2-B,分别采用荧光定量PCR和Western Blot法检测HK2 mRNA和蛋白的表达水平;MTT法检测细胞的增殖;Transwell小室检测细胞的迁移和侵袭;葡萄糖检测试剂盒检测细胞对葡萄糖的摄取.结果 与阴性对照组比较,siHK2能显著降低SK-BR-3细胞的HK2 mRNA及蛋白水平,抑制细胞增殖、迁移和侵袭能力,减少细胞对葡萄糖的摄取.结论 siHK2可能通过降低葡萄糖摄取来抑制SK-BR-3细胞的增殖、迁移和侵袭.
Objective To investigate the heregulin-β1 (HRG-β1)-induced expression of stearoyl-CoA desaturase-1 (SCD1) and the effect of its activity of SCD1 on the proliferation, migration and invasion of breast cancer cells MCF7 and SK-BR-3. Methods MCF7 and SK-BR-3 cells were treated with control (PBS) or HRG-β1 at different concentrations and for different times. Then RT-qPCR and Western blotting were used to detect the mRNA and protein expression levels of SCD1. The wound healing assay and Transwell assay were employed to measure the migration and invasion of MCF7 and SK-BR-3 cells treated with PBS, HRG-β1, A939572 and oleic acid (OA). Results HRG-β1 increased both SCD1 mRNA and protein levels in MCF7 and SK-BR-3 cells at a time-dose dependent manner. Compared with the control group, HRG-β1 promoted cell proliferation in MCF7 and SK-BR-3 cells (P < 0.01), while proliferation rate was decreased after A939572 treatment (P < 0.01). Compared with the control group, HRG-β1 significantly increased the wound healing rates and invaded cell numbers of MCF7 and SK-BR-3 cells (P < 0.01). The wound healing rates and invaded cell numbers of both cell lines were significantly decreased after HRG-β1+A939572 treatment (P < 0.01). The addition of OA rescued the migration and invasion of both cell lines which were weakened by A939572 (P < 0.01). Conclusions HRG-β1 can up-regulate the expression of SCD1, and the protein partially mediates the effect of HRG-β1 in promoting the proliferation, migration and invasion in MCF7 and SK-BR-3 cells.