scholarly journals Sirtuin 2 knockdown inhibits cell proliferation and RAS/ERK signaling, and promotes cell apoptosis and cell cycle arrest in multiple myeloma

2021 ◽  
Vol 24 (5) ◽  
Author(s):  
Tianling Ding ◽  
Jie Hao
2019 ◽  
Vol 51 (5) ◽  
pp. 517-523 ◽  
Author(s):  
Ting Zhang ◽  
Bo Li ◽  
Qilin Feng ◽  
Zhijian Xu ◽  
Cheng Huang ◽  
...  

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wenfeng He ◽  
Yonghui Fu ◽  
Yongliang Zheng ◽  
Xiaoping Wang ◽  
Bin Liu ◽  
...  

Abstract Background Side population (SP) cells, which have similar features to those of cancer stem cells, show resistance to dexamethasone (Dex) treatment. Thus, new drugs that can be used in combination with Dex to reduce the population of SP cells in multiple myeloma (MM) are required. Diallyl thiosulfinate (DATS, allicin), a natural organosulfur compound derived from garlic, has been shown to inhibit the proliferation of SP cells in MM cell lines. Therefore, we investigated the effect of a combination of DATS and Dex (DAT + Dex) on MM SP cells. Methods SP cells were sorted from MM RPMI-8226 and NCI-H929 cell lines using Hoechst 33342-labeled fluorescence-activated cell sorting. The growth of SP cells was evaluated using the cell counting kit-8 assay. Cell cycle and apoptosis assays were conducted using a BD Calibur flow cytometer. miRNA expression was measured using quantitative reverse transcription-polymerase chain reaction. Phosphoinositide 3-kinase (PI3K), phosphorylated AKT (p-AKT), AKT, p-mechanistic target of rapamycin (mTOR), and mTOR levels were measured using western blot analysis. Results Our results showed that the combination of DATS+Dex inhibited sphere formation, colony formation, and proliferation of MM SP cells by inducing apoptosis and cell cycle arrest in the G1/S phase. In addition, the combination of DATS+Dex promoted miR-127-3p expression and inhibited PI3K, p-AKT, and p-mTOR expression in SP cells. Knockdown of miR-127-3p expression weakened the effect of DATS+Dex on cell proliferation, colony formation, apoptosis, and cell cycle of MM SP cells. Additionally, knockdown of miR-127-3p activated the PI3K/AKT/mTOR signaling pathway in MM SP cells cotreated with DATS+Dex. Conclusion We demonstrated that cotreatment with DATS+Dex reduced cell proliferation, promoted apoptosis, and caused cell cycle arrest of MM SP cells by promoting miR-127-3p expression and deactivating the PI3K/AKT/mTOR signaling pathway.


Author(s):  
Hua Zhang ◽  
Xiaojin Zhao ◽  
Fajun Shang ◽  
Huan Sun ◽  
Xu Zheng ◽  
...  

Background: Colorectal cancer (CRC) is the third-ranked malignant tumor in the world that contributes to the death of a major population of the world. Celastrol, a bioactive natural product isolated from the medicinal plant Tripterygium wilfordii Hook F, has been proved to be an effective anti-tumor inhibitor for multiple tumors. Objective: To reveal the therapeutic effect and underlying mechanisms of celastrol on CRC cells. Methods: CCK-8 and clonogenic assay were used to analyze the cell proliferation in CRC cells. Flow cytometry analysis was conducted to assess the cell cycle and cell apoptosis. Wound-healing and cell invasion assay were used to evaluate the migrating and invasion capability of CRC cells. The potential antitumor mechanism of celastrol was investigated by qPCR, western blot, and confocal immunofluorescence analyses. Results: Celastrol effectively inhibited CRC cell proliferation by activating caspase-dependent cell apoptosis and facilitating G1 cell cycle arrest in a dose-dependent manner, as well as cell migration and invasion by downregulating the MMP2 and MMP9. Mechanistic protein expression revealed that celastrol suppressed the expression of COX-2 by inhibiting the phosphorylation of NF-κB p65 and subsequently leading to cytoplasmic retention of p65 protein, thereby inhibiting its nuclear translocation and transcription activities. Conclusion: These findings indicate that celastrol is an effective inhibitor for CRC, regulating the NF-κB/COX-2 pathway, leading to the inhibition of cell proliferation characterized by cell cycle arrest and caspase-dependent apoptosis, providing a potential alternative therapeutic agent for CRC patients.


2020 ◽  
Vol 245 (12) ◽  
pp. 1009-1015
Author(s):  
Jinhai Ren ◽  
Ying Wang ◽  
Lihua Wang ◽  
Xiaoling Guo ◽  
Xiaonan Guo

Myelodysplastic syndromes (MDSs) are a series of heterogeneous diseases affecting hematopoietic stem cells that result in hematopoiesis disturbance and leukemic transformation. As an essential cell cycle regulator, ribophorin II (RPN2) has been extensively identified as a prospective predictor of prognosis in diverse malignant tumors. However, its effects on MDS are unclear. We observed increased mRNA expression RPN2 in samples from MDS patients, compared with samples from normal healthy controls. RPN2 overexpression promoted the proliferation of Ontario Cancer Institute OCI-acute myeloid leukemia 3 (OCI-AML3) cells, whereas RPN2 silencing clearly suppressed the proliferation of OCI-AML3 cells. Furthermore, RPN2 silencing caused G1/S cell cycle arrest and cell apoptosis. In addition, RPN2 overexpression led to a higher proportion of cells in the G2/M phase and reduced cell apoptosis. RPN2 overexpression downregulated enhancer of zeste homolog-2 (EZH2) expression, whereas RPN2 downregulation increased EZH2 expression in a dose-dependent manner. Co-immunoprecipitation showed an interaction between RPN2 and EZH2. Additionally, the administration of 3-deazaneplanocin A, an EZH2 inhibitor, reversed the function of RPN2 silencing in cell cycle arrest and apoptosis induction in OCI-AML3 cells. Hence, RPN2 is an essential regulator of cell proliferation. This study described the etiology of OCI-AML3 cell proliferation regulated by RPN2 and EZH2. Impact statement This study explored the role of ribophorin II (RPN2) in myelodysplastic syndromes (MDSs) cell proliferation and growth and revealed that RPN2 knockdown suppressed OCI-AML3 cell growth and proliferation and triggered cell cycle arrest and elicited apoptosis in OCI-AML3 cells. In addition, it shed light on the etiology of RPN2’s role in MDS cell proliferation that RPN2 can negatively impact enhancer of zeste homolog-2 (EZH2) expression, which in turn is able to modulate the cell cycle location and death in OCI-AML3 cells. Hence, RPN2 expression could be a latent predictor of prognosis in patients with MDS.


2020 ◽  
Author(s):  
Di Wu ◽  
Hongyao Jia ◽  
Zhiru Zhang ◽  
Sijie Li

Abstract Background: Currently, long non-coding RNAs (lncRNAs) have been validated to exert critical influence on the malignant progression of triple-negative breast cancer (TNBC). LncRNA long intergenic non-protein coding RNA 504 (LINC00504) has been recently reported as a tumor facilitator in the cellular processes of several cancers. However, its function in TNBC remains unknown.Methods: CCK-8 and colony formation assays were used to detect the cell viability and proliferation in TNBC. Flow cytometry analysis was utilized to measure the cycle and apoptosis of TNBC cells. The levels of key proteins associated with cell apoptosis or the β-catenin pathway were detected through western blot analysis. The activity of the Wnt/β-catenin signaling pathway was measured by the TOP/FOP flash assay. ChIP assay was conducted to confirm the binding between LINC00504 and its transcription factor signal transducer and activator of transcription 3 (STAT3). RIP and luciferase reporter assays were used to detect and verify the interaction among LINC00504 and its downstream molecule.Results: LncRNA LINC00504 was upregulated in TNBC, and silenced LINC00504 suppressed cell proliferation and triggers cell cycle arrest at G0/G1 stage and cell apoptosis in TNBC cells. STAT3 can transcriptionally activate LINC00504 and LINC00504 served as a molecular sponge of microRNA (miR-4379). Kallikrein related peptidase 4 (KLK4) was the target gene of miR-4379 and activates the Wnt/β-catenin pathway. LINC00504 upregulated KLK4 via competitively binding with miR-4379 to activate the Wnt/β-catenin pathway in TNBC. The suppression on TNBC cell proliferation and the promotion on TNBC cell cycle arrest and apoptosis under LINC00504 knockdown were rescued by miR-4379 depletion or KLK4 overexpression.Conclusions: The LINC00504/miR-4379/KLK4 axis promotes cell growth and cell cycle progression as well as suppresses cell apoptosis through activating the Wnt/β-catenin pathway.


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