scholarly journals Autophagy Blockade by Ai Du Qing Formula Promotes Chemosensitivity of Breast Cancer Stem Cells Via GRP78/β-Catenin/ABCG2 Axis

2021 ◽  
Vol 12 ◽  
Author(s):  
Mianmian Liao ◽  
Caiwei Wang ◽  
Bowen Yang ◽  
Danping Huang ◽  
Yifeng Zheng ◽  
...  

Accumulating evidence suggests that the root of drug chemoresistance in breast cancer is tightly associated with subpopulations of cancer stem cells (CSCs), whose activation is largely dependent on taxol-promoting autophagy. Our pilot study identified GRP78 as a specific marker for chemoresistance potential of breast CSCs by regulating Wnt/β-catenin signaling. Ai Du Qing (ADQ) is a traditional Chinese medicine formula that has been utilized in the treatment cancer, particularly during the consolidation phase. In the present study, we investigated the regulatory effects and molecular mechanisms of ADQ in promoting autophagy-related breast cancer chemosensitivity. ADQ with taxol decreasing the cell proliferation and colony formation of breast cancer cells, which was accompanied by suppressed breast CSC ratio, limited self-renewal capability, as well as attenuated multi-differentiation. Furthermore, autophagy in ADQ-treated breast CSCs was blocked by taxol via regulation of β-catenin/ABCG2 signaling. We also validated that autophagy suppression and chemosensitizing activity of this formula was GRP78-dependent. In addition, GRP78 overexpression promoted autophagy-inducing chemoresistance in breast cancer cells by stabilizing β-catenin, while ADQ treatment downregulated GRP78, activated the Akt/GSK3β-mediated proteasome degradation of β-catenin via ubiquitination activation, and consequently attenuated the chemoresistance-promoted effect of GRP78. In addition, both mouse breast cancer xenograft and zebrafish xenotransplantation models demonstrated that ADQ inhibited mammary tumor growth, and the breast CSC subpopulation showed obscure adverse effects. Collectively, this study not only reveals the chemosensitizating mechanism of ADQ in breast CSCs, but also highlights the importance of GRP78 in mediating autophagy-promoting drug resistance via β-catenin/ABCG2 signaling.

2015 ◽  
Vol 112 (45) ◽  
pp. E6215-E6223 ◽  
Author(s):  
Huimin Zhang ◽  
Haiquan Lu ◽  
Lisha Xiang ◽  
John W. Bullen ◽  
Chuanzhao Zhang ◽  
...  

Increased expression of CD47 has been reported to enable cancer cells to evade phagocytosis by macrophages and to promote the cancer stem cell phenotype, but the molecular mechanisms regulating CD47 expression have not been determined. Here we report that hypoxia-inducible factor 1 (HIF-1) directly activates transcription of the CD47 gene in hypoxic breast cancer cells. Knockdown of HIF activity or CD47 expression increased the phagocytosis of breast cancer cells by bone marrow-derived macrophages. CD47 expression was increased in mammosphere cultures, which are enriched for cancer stem cells, and CD47 deficiency led to cancer stem cell depletion. Analysis of datasets derived from thousands of patients with breast cancer revealed that CD47 expression was correlated with HIF target gene expression and with patient mortality. Thus, CD47 expression contributes to the lethal breast cancer phenotype that is mediated by HIF-1.


2021 ◽  
Author(s):  
Ningwei Fu ◽  
Ning Fan ◽  
Wenchao Luo ◽  
Lijia Lv ◽  
Jing Li ◽  
...  

Abstract Purpose: TFEB is a key regulator of autophagy-lysosomal biogenesis pathways, while its dysregulation is highly prevalent in various human cancers, but the specific contribution to breast cancer remains poorly understood. The main purpose of this study is to explore the role of TFEB in breast cancer proliferation, metastasis and maintaining breast cancer stem cells (BCSCs) traits, thus uncovering its underlying mechanism.Methods: Bioinformatics, western blotting and immunohistochemical staining were applied to analyze the expression of TFEB in breast cancer. Stable down-regulation TFEB cells were established in MCF-7 and MDA-MB-231 breast cancer cell lines. MTT, clone formation, wound healing, transwell and 3D tumor invasion assays were used to evaluate the proliferation, migration and invasion ability of breast cancer cells. Mammosphere formation, immunocytochemical (ICC) staining were used to detect the effect of down-regulating TFEB on breast cancer stem cells. Results: we demonstrated that higher expression of TFEB was found in breast cancer. TFEB depletion had inhibitory effects on cellular proliferation, migration and invasion of breast cancer cells. Moreover, knockdown TFEB decreased mammosphere formation ability of BCSCs and expression of cancer stem cell markers. Autophagy-lysosomal related proteins were decreased by down regulation of TFEB. Conclusion: we uncovered a critical role of TFEB in breast cancer proliferation and metastasis, and BCSCs self-renewal and stemness. The underlying mechanisms involve in maintaining BCSCs traits, and dysregulating lysosome functions.


Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4350
Author(s):  
Jessica Castro ◽  
Giusy Tornillo ◽  
Gerardo Ceada ◽  
Beatriz Ramos-Neble ◽  
Marlon Bravo ◽  
...  

Despite the significant advances in cancer research made in recent years, this disease remains one of the leading causes of death worldwide. In part, this is due to the fact that after therapy, a subpopulation of self-renewing tumor cells can survive and promote cancer relapse, resistance to therapies and metastasis. Targeting these cancer stem cells (CSCs) is therefore essential to improve the clinical outcome of cancer patients. In this sense, multi-targeted drugs may be promising agents targeting CSC-associated multifocal effects. We have previously constructed different human pancreatic ribonuclease (RNase) variants that are cytotoxic for tumor cells due to a non-classical nuclear localization signal introduced in their sequence. These cytotoxic RNases affect the expression of multiple genes involved in deregulated metabolic and signaling pathways in cancer cells and are highly cytotoxic for multidrug-resistant tumor cell lines. Here, we show that these cytotoxic nuclear-directed RNases are highly selective for tumor cell lines grown in 3D, inhibit CSCs’ development and diminish the self-renewal capacity of the CSCs population. Moreover, these human RNase variants reduce the migration and invasiveness of highly invasive breast cancer cells and downregulate N-cadherin expression.


Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1133
Author(s):  
Ji Yu ◽  
Dae Shin ◽  
Jin-Seok Kim

Fluvastatin (FLUVA), which is a common anti-hypercholesterolemia drug, exhibits potential anticancer activity as it suppresses the proliferation, angiogenesis, and metastasis of breast cancer cells via inhibiting 3-hydroxy-methyl glutaryl-coenzyme A (HMG-CoA) reductase. In this study, hyaluronan-conjugated FLUVA-encapsulating liposomes (HA-L-FLUVA) were evaluated for their anticancer efficacy in vitro and in vivo. The particle size, zeta potential, and encapsulation efficiency of HA-L-FLUVA were 158.36 ± 1.78 nm, −24.85 ± 6.26 mV, and 35%, respectively. Growth inhibition of breast cancer stem cells (BCSCs) by HA-L-FLUVA was more effective than that by free FLUVA. The half maximal inhibitory concentration (IC50) values of FLUVA, L-FLVUA, and HA-L-FLUVA were 0.16, 0.17, and 0.09 μM, respectively. The in vivo anticancer effect of HA-L-FLUVA in combination with doxorubicin (DOX) was more effective than that of free FLUVA, free DOX, and HA-L-FLUVA. The longest survival of mice was achieved by treatment with FLUVA (15 mg/kg) and HA-L-FLUVA (15 mg/kg) + DOX (3 mg/kg), followed by HA-L-FLUVA (15 mg/kg), Dulbecco’s phosphate buffered saline, and DOX (3 mg/kg). No more than 10% body weight loss was observed in the mice injected with FLUVA, indicating that the drug was not toxic. Taken together, these results indicate that HA-L-FLUVA could serve as an effective anticancer drug by inhibiting the growth of both breast cancer cells and cancer stem cells.


2019 ◽  
Vol 2 (10) ◽  
pp. 4622-4633 ◽  
Author(s):  
Dong-Min Kim ◽  
Minhee Kim ◽  
Hee-Bin Park ◽  
Keun-Sik Kim ◽  
Dong-Eun Kim

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