Redox Regulation in Cancer Stem Cells

Reactive oxygen species (ROS) and ROS-dependent (redox regulation) signaling pathways and transcriptional activities are thought to be critical in stem cell self-renewal and differentiation during growth and organogenesis. Aberrant ROS burst and dysregulation of those ROS-dependent cellular processes are strongly associated with human diseases including many cancers. ROS levels are elevated in cancer cells partially due to their higher metabolism rate. In the past 15 years, the concept of cancer stem cells (CSCs) has been gaining ground as the subpopulation of cancer cells with stem cell-like properties and characteristics have been identified in various cancers. CSCs possess low levels of ROS and are responsible for cancer recurrence after chemotherapy or radiotherapy. Unfortunately, how CSCs control ROS production and scavenging and how ROS-dependent signaling pathways contribute to CSCs function remain poorly understood. This review focuses on the role of redox balance, especially in ROS-dependent cellular processes in cancer stem cells (CSCs). We updated recent advances in our understanding of ROS generation and elimination in CSCs and their effects on CSC self-renewal and differentiation through modulating signaling pathways and transcriptional activities. The review concludes that targeting CSCs by manipulating ROS metabolism/dependent pathways may be an effective approach for improving cancer treatment.

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Abnormal Glycosylation of Cancer Stem Cells and Targeting Strategies

Frontiers in Oncology ◽

10.3389/fonc.2021.649338 ◽

2021 ◽

Vol 11 ◽

Author(s):

Thahomina Khan ◽

Horacio Cabral

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Stem Cell ◽

Signaling Pathways ◽

Intracellular Signaling ◽

Self Renewal ◽

Tumor Relapse ◽

Intracellular Signaling Pathways ◽

Abnormal Glycosylation

Cancer stem cell (CSCs) are deemed as one of the main reasons of tumor relapse due to their resistance to standard therapies. Numerous intracellular signaling pathways along with extracellular features are crucial in regulating CSCs properties, such as heterogeneity, plasticity and differentiation. Aberrant glycosylation of these cellular signaling pathways and markers of CSCs have been directly correlated with maintaining survival, self-renewal and extravasation properties. In this review, we highlight the importance of glycosylation in promoting stemness character of CSCs, and present strategies for targeting abnormal glycosylation to eliminate the resistant CSC population.

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Sulforaphane Inhibits Self-renewal of Lung Cancer Stem Cells Through the Modulation of Polyhomeotic Homolog 3 and Sonic Hedgehog Signaling Pathways

10.21203/rs.2.11459/v1 ◽

2019 ◽

Author(s):

FanPing Wang ◽

Jiateng Zhong ◽

Shanshan Wang ◽

Caijuan Qiao ◽

Xiangyang Li ◽

...

Keyword(s):

Lung Cancer ◽

Stem Cells ◽

Cancer Stem Cells ◽

Western Blot ◽

Cancer Cells ◽

Signaling Pathways ◽

Sonic Hedgehog ◽

Self Renewal ◽

Shh Signaling ◽

Lung Cancer Stem Cells

Abstract Background: Sulforaphane (SFN), an active compound in cruciferous vegetables has been characterized for its antiproliferative capacity. We investigated the role and molecular mechanism through which SFN regulates proliferation and self-renewal of lung cancer stem cells. Methods: Lung cancer stem cells (CD133-positive cells) were isolated by MACs and then measured by flow cytometry. The ability of cell proliferation was assessed by MTT assays and tumorsphere formation assays. The expressions of Sonic Hedgehog (Shh), Smoothened (Smo), Gli1 and Human Polyhomeotic Homolog 3 (PHC3) in cells were measured by quantitative reverse transcription polymerase chain reaction (qPCR) and western blot assays. The expression of transcription factor SOX2 in lung cancer stem cells was also determined by western blot assay. Shh was knocked down by siRNA to further study the role of SFN and Shh signaling pathways in lung cancer. Results: SFN inhibited the proliferation of lung cancer cells and lung cancer stem cells simultaneously. Meanwhile, we observed that Sonic Hedgehog (SHH) signaling pathway, SOX2 and Polyhomeotic Homolog 3 (PHC3) were highly activated in lung cancer stem cells. Knock-down of Shh led to reduced H460 and A549 cells proliferation. Furthermore, we observed that SFN inhibited the activity of PHC3 and SHH signaling pathways in the lung cancer stem cells. In addition, SFN combined with Knock-down of Shh gene showed a greater effect on the proliferation of lung cancer cells. Conclusion: SFN is an effective new drug which can inhibit proliferation of lung cancer stem cells through the modulation of PHC3 and SHH signaling pathways. It provides a novel target for improving therapeutic efficacy for lung cancer stem cells.

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Deubiquitinating Enzyme-Mediated Signaling Networks in Cancer Stem Cells

Cancers ◽

10.3390/cancers12113253 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3253

Author(s):

Kamini Kaushal ◽

Suresh Ramakrishna

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Signaling Pathways ◽

Cell Fate ◽

Deubiquitinating Enzymes ◽

Self Renewal ◽

Stem Cell Fate ◽

Multiple Tumor ◽

Cell Fate Decisions

Cancer stem cells (CSCs) have both the capacity for self-renewal and the potential to differentiate and contribute to multiple tumor properties, such as recurrence, metastasis, heterogeneity, multidrug resistance, and radiation resistance. Thus, CSCs are considered to be promising therapeutic targets for cancer therapy. The function of CSCs can be regulated by ubiquitination and deubiquitination of proteins related to the specific stemness of the cells executing various stem cell fate choices. To regulate the balance between ubiquitination and deubiquitination processes, the disassembly of ubiquitin chains from specific substrates by deubiquitinating enzymes (DUBs) is crucial. Several key developmental and signaling pathways have been shown to play essential roles in this regulation. Growing evidence suggests that overactive or abnormal signaling within and among these pathways may contribute to the survival of CSCs. These signaling pathways have been experimentally shown to mediate various stem cell properties, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation. In this review, we focus on the DUBs involved in CSCs signaling pathways, which are vital in regulating their stem-cell fate determination.

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Natural Compounds Targeting Cancer Stem Cells: A Promising Resource for Chemotherapy

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520619666190704111714 ◽

2019 ◽

Vol 19 (15) ◽

pp. 1796-1808 ◽

Cited By ~ 2

Author(s):

Plabon K. Das ◽

Tasnim Zahan ◽

Md. Abdur Rakib ◽

Jahan A. Khanam ◽

Suja Pillai ◽

...

Keyword(s):

Stem Cells ◽

Cancer Stem Cells ◽

Cancer Cells ◽

Signaling Pathways ◽

Cancer Recurrence ◽

Therapy Resistance ◽

Natural Compounds ◽

Biologically Active ◽

Cancer Pathogenesis ◽

Distant Organ

Background:Cancer Stem Cells (CSCs) are the subpopulation of cancer cells which are directly involved in drug resistance, metastases to distant organ and cancer recurrence.Methods:A systematic literature search was conducted through various electronic databases including, Pubmed, Scopus, Google scholar using the keywords "cancer stem cells" and "natural compounds" in the present study. Articles published between 1999 and 2019 were reviewed. All the expositions concerning CSCs associated cancer pathogenesis and therapy resistance, as well as targeting these properties of CSCs by natural compounds were selected for the current study.Results:Natural compounds have always been thought as a rich source of biologically active principles, which target aberrantly activated signaling pathways and other modalities of CSCs, while tethering painful side effects commonly involved in the first-line and second-line chemo-radiotherapies. In this review, we have described the key signaling pathways activated in CSCs to maintain their survival and highlighted how natural compounds interrupt these signaling pathways to minimize therapy resistance, pathogenesis and cancer recurrence properties of CSCs, thereby providing useful strategies to treat cancer or aid in cancer therapy improvement. Like normal stem cells, CSCs rely on different signaling pathways and other properties for their maintenance. Therefore, the success of cancer treatment depends on the development of proper anti-neoplastic drugs capable of intercepting those signaling pathways as well as other properties of CSCs in order to eradicate this evasive subpopulation of cancer cells.Conclusion:Compounds of natural origin might act as an outstanding source to design novel therapies against cancer stem cells.

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Sulforaphane Inhibits Self-renewal of Lung Cancer Stem Cells Through the Modulation of Sonic Hedgehog Signaling Pathway and Polyhomeotic Homolog3

10.21203/rs.3.rs-165086/v1 ◽

2021 ◽

Author(s):

FanPing Wang ◽

Yanwei Sun ◽

Xiaoyu Huang ◽

Caijuan Qiao ◽

Wenrui Zhang ◽

...

Keyword(s):

Lung Cancer ◽

Stem Cells ◽

Cancer Stem Cells ◽

Protein Expression ◽

Cancer Cells ◽

Signaling Pathways ◽

Sonic Hedgehog ◽

Self Renewal ◽

Shh Signaling ◽

Lung Cancer Stem Cells

Abstract Sulforaphane (SFN), an active compound in cruciferous vegetables has been characterized for its antiproliferative capacity. We investigated the role and molecular mechanism through which SFN regulates proliferation and self-renewal of lung cancer stem cells (CSCs). CD133-positive lung cancer cells were isolated by MACs from lung cancer A549 and H460 cells. And then, the expression of CD133 was measured by flow cytometry assays (FACS). The ability of cell proliferation was assessed by MTT assays and tumorsphere formation assays. The mRNA expression of Sonic Hedgehog (Shh), Smoothened (Smo), Gli1 and Human Polyhomeotic Homolog 3 (PHC3) was measured by quantitative reverse transcription polymerase chain reaction (QPCR). And the protein expression of Shh, Smo, Gli1 and PHC3 was determined by western blotting. Shh was knocked down by siRNA to further study the role of Shh signaling pathways in lung CSCs. SFN inhibited the proliferation of lung cancer cells and lung CSCs simultaneously. Meanwhile, the mRNA and protein expressions of Shh, Smo, Gli1 and PHC3 were highly activated in A549 /CD133+ and H460 /CD133+ cells. Compared with siRNA-control group, Knock-down of Shh inhibited proliferation of A549/ CD133+ and H460/ CD133+ cells, and decreased the protein expression of PHC3 in A549/ CD133+ and H460/ CD133+ cells. In addition, SFN inhibited the activities of Shh, Smo, Gli1 and PHC3 in A549/ CD133+ and H460/ CD133+ cells. Furthermore, the inhibitory effect of SFN on the proliferation of siRNA-shh cells is weaker than that of siRNA-control cells. SFN is an effective new drug which can inhibit proliferation of lung CSCs through the modulation of PHC3 and SHH signaling pathways. It provides a novel target for improving therapeutic efficacy for lung CSCs.

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TGFβ Family Signaling Pathways in Pluripotent and Teratocarcinoma Stem Cells’ Fate Decisions: Balancing Between Self-Renewal, Differentiation, and Cancer

Cells ◽

10.3390/cells8121500 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1500 ◽

Cited By ~ 6

Author(s):

Olga Gordeeva

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Signaling Pathways ◽

Pluripotent Stem Cells ◽

Family Factors ◽

State Transitions ◽

Functional Impairments ◽

Differentiation Potential ◽

Self Renewal ◽

Cellular Processes

The transforming growth factor-β (TGFβ) family factors induce pleiotropic effects and are involved in the regulation of most normal and pathological cellular processes. The activity of different branches of the TGFβ family signaling pathways and their interplay with other signaling pathways govern the fine regulation of the self-renewal, differentiation onset and specialization of pluripotent stem cells in various cell derivatives. TGFβ family signaling pathways play a pivotal role in balancing basic cellular processes in pluripotent stem cells and their derivatives, although disturbances in their genome integrity induce the rearrangements of signaling pathways and lead to functional impairments and malignant transformation into cancer stem cells. Therefore, the identification of critical nodes and targets in the regulatory cascades of TGFβ family factors and other signaling pathways, and analysis of the rearrangements of the signal regulatory network during stem cell state transitions and interconversions, are key issues for understanding the fundamental mechanisms of both stem cell biology and cancer initiation and progression, as well as for clinical applications. This review summarizes recent advances in our understanding of TGFβ family functions in naїve and primed pluripotent stem cells and discusses how these pathways are involved in perturbations in the signaling network of malignant teratocarcinoma stem cells with impaired differentiation potential.

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Review on Research about Traditional Chinese Medicine in Cancer Stem Cell

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2017/4505194 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Yaohan Wang ◽

Li Feng ◽

Bingkui Piao ◽

Peitong Zhang

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Chinese Medicine ◽

Traditional Chinese Medicine ◽

Cancer Stem Cells ◽

Cancer Recurrence ◽

Basic Research ◽

Inhibitory Effect ◽

Self Renewal ◽

New Strategies

Cancer stem cells (CSCs) are small subpopulations of neoplastic cells within a tumor, which have self-renewal and differentiation abilities and could generate new tumors with few cells. Researches have showed that CSCs are considered the most likely reason for cancer recurrence and metastasis. Accumulating evidences have showed that traditional Chinese medicine (TCM) has significant effect on CSCs. It could inhibit the proliferation, self-renew, and multidifferentiation of CSCs. We aimed to summarize the theories of CSCs in TCM, the inhibitory effect, and the pathway on CSCs of TCM. This review will provide potential new strategies and alternative perspectives for CSCs treatments and basic research into complementary and alternative medicine.

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Integrin α6 (CD49f), The Microenvironment and Cancer Stem Cells

Current Stem Cell Research & Therapy ◽

10.2174/1574888x13666181002151330 ◽

2019 ◽

Vol 14 (5) ◽

pp. 428-436 ◽

Cited By ~ 4

Author(s):

Gabriele D. Bigoni-Ordóñez ◽

Daniel Czarnowski ◽

Tyler Parsons ◽

Gerard J. Madlambayan ◽

Luis G. Villa-Diaz

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Stem Cell ◽

The Self ◽

Self Renewal ◽

Terminal Disease

Cancer is a highly prevalent and potentially terminal disease that affects millions of individuals worldwide. Here, we review the literature exploring the intricacies of stem cells bearing tumorigenic characteristics and collect evidence demonstrating the importance of integrin α6 (ITGA6, also known as CD49f) in cancer stem cell (CSC) activity. ITGA6 is commonly used to identify CSC populations in various tissues and plays an important role sustaining the self-renewal of CSCs by interconnecting them with the tumorigenic microenvironment.

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Cancer stemness as a target for immunotherapy is shaped by pro-inflammatory stress.

Current Stem Cell Research & Therapy ◽

10.2174/1574888x15666200309145901 ◽

2020 ◽

Vol 15 ◽

Author(s):

Nese Unver

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Immune Cells ◽

Tumor Recurrence ◽

Inflammatory Factors ◽

Cancer Stemness ◽

Self Renewal ◽

Inflammatory Stress ◽

Factors Affecting

: Cancer stem cells represent a rare subpopulation of cancer cells carrying self-renewal and differentiation features in the multi-step tumorigenesis, tumor recurrence and metastasis. Pro-inflammatory stress is highly associated with cancer stemness via induction of cytokines, tumor-promoting immune cells and cancer stemness-related signaling pathways. This review summarizes the major pro-inflammatory factors affecting cancer stem cell characteristics and the critical immunotherapeutic strategies to eliminate cancer stem cells.

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HER2 decreases drug sensitivity of ovarian cancer cells via inducing stem cell-like property in an NFκB-dependent way

Bioscience Reports ◽

10.1042/bsr20180829 ◽

2019 ◽

Vol 39 (3) ◽

Cited By ~ 1

Author(s):

Wenxiang Wang ◽

Yuxia Gao ◽

Jing Hai ◽

Jing Yang ◽

Shufeng Duan

Keyword(s):

Ovarian Cancer ◽

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Cells ◽

Drug Sensitivity ◽

Ovarian Cancer Cells ◽

Her2 Overexpression ◽

Her2 Positive ◽

Ovarian Cancer Stem Cells

Abstract Increasing evidence shows that cancer stem cells are responsible for drug resistance and relapse of tumors. In breast cancer, human epidermal growth factor receptor 2 (HER2) induces Herceptin resistance by inducing cancer stem cells. In the present study, we explored the effect of HER2 on cancer stem cells induction and drug sensitivity of ovarian cancer cell lines. First, we found that HER2 overexpression (HER2 OE) induced, while HER2 knockdown (HER2 KD) decreased CD44+/CD24− population. Consistently, HER2 expression was closely correlated with the sphere formation efficiency (SFE) of ovarian cancer cells. Second, we found that NFκB inhibition by specific inhibitor JSH23 or siRNA targetting subunit p65 dramatically impaired the induction of ovarian cancer stem cells by HER2, indicating that NFκB mediated HER2-induced ovarian cancer stem cells. Third, we found that HER2 KD significantly attenuated the tumorigenicity of ovarian cancer cells. Further, we found that HER2 inhibition increased drastically the sensitivity of ovarian cancer cells to doxorubicin (DOX) or paclitaxel (PTX). Finally, we examined the correlation between HER2 status and stem cell-related genes expression in human ovarian tumor tissues, and found that expressions of OCT4, COX2, and Nanog were higher in HER2 positive tumors than in HER2 negative tumors. Consistently, the 5-year tumor-free survival rate of HER2 positive patients was dramatically lower than HER2 negative patients. Taken together, our data indicate that HER2 decreases drug sensitivity of ovarian cancer cells via inducing stem cell-like property.

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