scholarly journals Differential Expression of MicroRNA-19b Promotes Proliferation of Cancer Stem Cells by Regulating the TSC1/mTOR Signaling Pathway in Multiple Myeloma

2018 ◽  
Vol 50 (5) ◽  
pp. 1804-1814 ◽  
Author(s):  
Ni Wang ◽  
Xiaohua Liang ◽  
Weijian Yu ◽  
Shihang Zhou ◽  
Meiyun  Fang

Background/Aims: MiR-19b has been reported to be involved in several malignancies, but its role in multiple myeloma (MM) is still unknown. The objective of this study was to explore the biological mechanism of miR-19b in the progression of MM. Methods: First, we performed real-time polymerase chain reaction (PCR) and Western blot to study the expression of miR-19b, tuberous sclerosis 1 (TSC1), and caspase-3 in different groups. MTT assay was performed to explore the effect of miR-19b on survival and apoptosis of cancer stem cells (CSCs). Computation analysis and luciferase assay were utilized to confirm the interaction between miR-19b and TSC1. Results: A total of 38 participants comprising 20 subjects with MM and 18 healthy subjects as normal controls were enrolled in our study. Real-time PCR showed dramatic upregulation of miR-19b, but TSC1 was evidently suppressed in the MM group. MiR-19b overexpression substantially promoted clonogenicity and cell viability, and further inhibited apoptosis of CSCs in vitro. Furthermore, miR-19b overexpression downregulated the expression of caspase-3, which induced apoptosis. Using in silico analysis, we identified that TSC1 might be a direct downstream target of miR-19b, and this was further confirmed by luciferase assay showing that miR-19b apparently reduced the luciferase activity of wild-type TSC1 3´-UTR, but not that of mutant TSC1 3´-UTR. There was also evident decrease in TSC1 mRNA and protein in CSCs following introduction of miR-19b. Interestingly, reintroduction of TSC1 abolished the miR-19b-induced proliferation promotion and apoptosis inhibition in CSCs. Conclusion: These findings collectively suggest that miR-19b promotes cell survival and suppresses apoptosis of MM CSCs via targeting TSC1 directly, indicating that miR-19b may serve as a potential and novel therapeutic target of MM based on miRNA expression.

Gut ◽  
2021 ◽  
pp. gutjnl-2020-321175
Author(s):  
Shumei Song ◽  
Qiongrong Chen ◽  
Yuan Li ◽  
Guang Lei ◽  
Ailing Scott ◽  
...  

ObjectiveGastro-oesophageal cancers (GEC) are resistant to therapy and lead to poor prognosis. The cancer stem cells (CSCs) and antiapoptotic pathways often confer therapy resistance. We sought to elucidate the antitumour action of a BCL-2 inhibitor, AT101 in GEC in vitro, in vivo and in a clinical trial.MethodsExtensive preclinical studies in vitro and in vivo were carried out to establish the mechanism action of AT101 on targeting CSCs and antiapoptotic proteins. A pilot clinical trial in patients with GEC was completed with AT-101 added to standard chemoradiation.ResultsOverexpression of BCL-2 and MCL-1 was noted in gastric cancer tissues (GC). AT-101 induced apoptosis, reduced proliferation and tumour sphere formation in MCL-1/BCL-2 high GC cells. Interestingly, AT101 dramatically downregulated genes (YAP-1/Sox9) that control CSCs in GEC cell lines regardless of BCL-2/MCL-1 expression. Addition of docetaxel to AT-101 amplified its antiproliferation and induced apoptosis effects. In vivo studies confirmed the combination of AT101 and docetaxel demonstrated stronger antitumour activity accompanied with significant decrease of CSCs biomarkers (YAP1/SOX9). In a pilot clinical trial, 13 patients with oesophageal cancer (EC) received AT101 orally concurrently with chemoradiation. We observed dramatic clinical complete responses and encouraging overall survival in these patients. Clinical specimen analyses revealed that AT-101 dramatically reduced the expression of CSCs genes in treated EC specimens indicating antitumour activity of AT101 relies more on its anti-CSCs activity.ConclusionsOur preclinical and clinical data suggest that AT-101 overcomes resistance by targeting CSCs pathways suggesting a novel mechanism of action of AT101 in patients with GEC.


2015 ◽  
Vol 112 (14) ◽  
pp. 4411-4416 ◽  
Author(s):  
Amit Kumar Srivastava ◽  
Chunhua Han ◽  
Ran Zhao ◽  
Tiantian Cui ◽  
Yuntao Dai ◽  
...  

Cancer stem cells (CSCs) with enhanced tumorigenicity and chemoresistance are believed to be responsible for treatment failure and tumor relapse in ovarian cancer patients. However, it is still unclear how CSCs survive DNA-damaging agent treatment. Here, we report an elevated expression of DNA polymerase η (Pol η) in ovarian CSCs isolated from both ovarian cancer cell lines and primary tumors, indicating that CSCs may have intrinsically enhanced translesion DNA synthesis (TLS). Down-regulation of Pol η blocked cisplatin-induced CSC enrichment both in vitro and in vivo through the enhancement of cisplatin-induced apoptosis in CSCs, indicating that Pol η-mediated TLS contributes to the survival of CSCs upon cisplatin treatment. Furthermore, our data demonstrated a depletion of miR-93 in ovarian CSCs. Enforced expression of miR-93 in ovarian CSCs reduced Pol η expression and increased their sensitivity to cisplatin. Taken together, our data suggest that ovarian CSCs have intrinsically enhanced Pol η-mediated TLS, allowing CSCs to survive cisplatin treatment, leading to tumor relapse. Targeting Pol η, probably through enhancement of miR-93 expression, might be exploited as a strategy to increase the efficacy of cisplatin treatment.


2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Wenwen Deng ◽  
Yan Wang ◽  
Xianping Long ◽  
Ranzun Zhao ◽  
Zhenglong Wang ◽  
...  

The low survival rate of cardiac stem cells (CSCs) in the infarcted myocardium hampers cell therapy for ischemic cardiomyopathy. MicroRNA-21 (miR-21) and one of its target proteins, PTEN, contribute to the survival and proliferation of many cell types, but their prosurvival effects in c-kit+CSC remain unclear. Thus, we hypothesized that miR-21 reduces hydrogen peroxide- (H2O2-) induced apoptosis in c-kit+CSC and estimated the contribution of PTEN/PI3K/Akt signaling to this oxidative circumstance. miR-21 mimics efficiently reduced H2O2-induced apoptosis in c-kit+CSC, as evidenced by the downregulation of the proapoptosis proteins caspase-3 and Bax and upregulation of the antiapoptotic Bcl-2. In addition, the gain of function of miR-21 in c-kit+CSC downregulated the protein level of PTEN although its mRNA level changed slightly; in the meantime, miR-21 overexpression also increased phospho-Akt (p-Akt). The antiapoptotic effects of miR-21 were comparable with Phen (bpV), the selective inhibitor of PTEN, while miR-21 inhibitor or PI3K’s inhibitor LY294002 efficiently attenuated the antiapoptotic effect of miR-21. Taken together, these results indicate that the anti-H2O2-induced apoptosis effect of miR-21 in c-kit+CSC is contributed by PTEN/PI3K/Akt signaling. miR-21 could be a potential molecule to facilitate the c-kit+CSC therapy in ischemic myocardium.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0240020
Author(s):  
Septelia Inawati Wanandi ◽  
Agus Limanto ◽  
Elvira Yunita ◽  
Resda Akhra Syahrani ◽  
Melva Louisa ◽  
...  

Breast cancer stem cells (BCSCs) express high levels of the anti-apoptotic protein, survivin. This study aimed to discover a natural active compound with anti-cancer properties that targeted survivin in human breast cancer stem cells. From the seven examined compounds, andrographolide was selected as a lead compound through in silico molecular docking with survivin, caspase-9, and caspase-3. We found that the affinity between andrographolide and survivin is higher than that with caspase-9 and caspase-3. Human CD24-/CD44+ BCSCs were treated with andrographolide in vitro for 24 hours. The cytotoxic effect of andrographolide on BCSCs was compared to that on human mesenchymal stem cells (MSCs). The expression of survivin, caspase-9, and caspase-3 mRNA was analyzed using qRT-PCR, while Thr34-phosphorylated survivin and total survivin levels were determined using ELISA and Immunoblotting assay. Annexin-V/PI flow cytometry assays were performed to evaluate the apoptotic activity of andrographolide. Our results demonstrate that the CC50 of andrographolide in BCSCs was 0.32mM, whereas there was no cytotoxic effect in MSCs. Moreover, andrographolide decreased survivin and Thr34-phosphorylated survivin, thus inhibiting survivin activation and increasing survivin mRNA in BCSCs. The apoptotic activity of andrographolide was revealed by the increase of caspase-3 mRNA and protein, as well as the increase in both the early and late phases of apoptosis. In conclusion, andrographolide can be considered an anti-cancer compound that targets BCSCs due to its molecular interactions with survivin, caspase-9, and caspase-3, which induce apoptosis. We suggest that the binding of andrographolide to survivin is a critical aspect of the effect of andrographolide.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Yunsheng Zhang ◽  
Luogen Liu ◽  
Fang Li ◽  
Tao Wu ◽  
Hongtao Jiang ◽  
...  

Salinomycin is an antibiotic isolated from Streptomyces albus that selectively kills cancer stem cells (CSCs). However, the antitumor mechanism of salinomycin is unclear. This study investigated the chemotherapeutic efficacy of salinomycin in human prostate cancer PC-3 cells. We found that cytotoxicity of salinomycin to PC-3 cells was stronger than to nonmalignant prostate cell RWPE-1, and exposure to salinomycin induced G2/M phage arrest and apoptosis of PC-3 cells. A mechanistic study found salinomycin suppressed Wnt/β-catenin pathway to induce apoptosis of PC-3 cells. An in vivo experiment confirmed that salinomycin suppressed tumorigenesis in a NOD/SCID mice xenograft model generated from implanted PC-3 cells by inhibiting the Wnt/β-catenin pathway, since the total β-catenin protein level was reduced and the downstream target c-Myc level was significantly downregulated. We also showed that salinomycin, but not paclitaxel, triggered more apoptosis in aldehyde dehydrogenase- (ALDH-) positive PC-3 cells, which were considered as the prostate cancer stem cells, suggesting that salinomycin may be a promising chemotherapeutic to target CSCs. In conclusion, this study suggests that salinomycin reduces resistance and relapse of prostate tumor by killing cancer cells as well as CSCs.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Amal Charindra Hulangamuwa ◽  
Meran Keshawa Ediriweera ◽  
Umapriyatharshini Rajagopalan ◽  
Desiree Nedra Karunaratne ◽  
Kamani Hemamala Tennekoon ◽  
...  

Garcinol (GA), a polyisoprenylated benzophenone derivative, is one of the major phytochemicals found in a number of fruits of Garcinia. This study aimed to develop a new nanodelivery system comprising GA, hyaluronic acid (HA), and poly(lactic-co-glycolic acid) (PLGA) to actively target breast cancer stem cells (bCSCs) grown under hypoxic conditions. HA has been reported to show higher affinity for the cluster-determinant 44 receptor (CD44), while PLGA is an FDA-approved biodegradable polymer used in clinical applications. Nanoparticles (NPs) were prepared by emulsion solvent diffusion technique using DMAB as the emulsifier. Following preparation, particle size, surface charge, and polydispersity index of NPs were characterized. Antiproliferative effects of NPs were assessed by the WST-1 cell proliferation assay. Apoptotic effects of NPs were evaluated by the caspase-3/7 assay. Effects of prepared NPs on the expression of genes related to hypoxia-inducing factors (HIF-1α and HIF-2α) and notch ligands (DLL1 and Jagged1) were evaluated using real-time PCR. HA-coated garcinol-loaded NPs (HA-GA-NPs) showed greater antiproliferative effects in bCSCs grown under hypoxia. Moreover, HA-GA-NPs showed an improved cellular uptake via receptor-mediated endocytosis compared to non-HA-coated GA-NPs. Exposure to GA-HA-NPs resulted in a significant downregulation in hypoxia-inducing factors and notch pathway-related genes. Activation of caspase-3/7 confirmed the HA-GA-NPs can induce apoptosis in bCSCs. Overall findings of the study confirm that HA-GA-NPs can be considered as an effective nanodelivery system to target bCSCs grown under the hypoxic microenvironment.


MedChemComm ◽  
2017 ◽  
Vol 8 (1) ◽  
pp. 112-121 ◽  
Author(s):  
Mark E. Issa ◽  
Muriel Cuendet

Withaferin A induced the differentiation of multiple myeloma cancer stem cells in vitro, and altered the expression of stemness and differentiation markers.


Author(s):  
Merve Erkisa ◽  
Nazlihan Aztopal ◽  
Elif Erturk ◽  
Engin Ulukaya ◽  
Veysel T. Yilmaz ◽  
...  

Background: Cancer stem cells (CSC) are subpopulation within the tumor that acts a part in the initiation, progression, recurrence, resistance to drugs and metastasis of cancer. It is well known that epigenetic changes lead to tumor formation in cancer stem cells and show drug resistance. Epigenetic modulators and /or their combination with different agents have been used in cancer therapy. Objective: In our study we scope out the effects of combination of a histone deacetylases inhibitor, valproic acid (VPA), and Cu(II) complex [Cu(barb-κN)(barb-κ2N,O)(phen-κN,N’)]·H2O] on cytotoxicity/apoptosis in a stem-cell enriched population (MCF-7s) obtained from parental breast cancer cell line (MCF-7). Methods: Viability of the cells was measured by the ATP assay. Apoptosis was elucidated via the assessment of caspase-cleaved cytokeratin 18 (M30 ELISA) and a group of flow cytometry analysis (caspase 3/7 activity, phosphatidylserine translocation by annexin V-FITC assay, DNA damage and oxidative stress) and 2ˈ,7ˈ–dichlorofluorescein diacetate staining. Results: The VPA combined with Cu(II) complex showed anti proliferative activity on MCF-7s cells in a dose- and time-dependently. Treatment with combination of 2.5 mM VPA and 3.12 μM Cu(II) complex induces oxidative stress in a time-dependent manner, as well as apoptosis that is evidenced by the increase in caspase 3/7 activity, positive annexin-V-FITC, and increase in M30 levels. Conclusion: The results suggest that the combination therapy induces apoptosis following increased oxidative stress, thereby making it a possible promising therapeutic strategy that further analysis is required.


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