Moonlighting Role of PEDF in Breast Cancer

Abstract Background: Breast cancer is the leading cause of death among females in developed countries. Although the implementation of screening tests and the development of new therapies has increased the probability of remission, relapse rates still remain high. Numerous studies have indicated the connection between cancer initiating cells and slow cellular cycle cells, identified by their capacity to retain long labelling (LT+). Methods: We have designed a transgenic protein consisting in the C-terminal part of this protein, which acts by blocking endogenous PEDF in culture cell assays. Present work is based in doses-response in vitro assays as well as flow cytometry analysis of surface markers and cell cycle kinetic study of the tumour initiating cells.Results: In this study we show that this type of cells is present not only in cancer cell lines but also in cancer cells from patients with metastatic and advanced stage tumours. We also present new assays showing how stem cell self-renewal modulating proteins, such as PEDF, can modify the properties, expression of markers, and carcinogenicity of cancer stem cells. This protein has been involved in self-renewal in adult stem cells and has been described as anti-tumoral because of its anti-angiogenic effect. However, we show that PEDF enhances resistance in breast cancer patient cells in vitro culture by favoring a slow cellular cycle population (LT+). The PEDF signalling pathway could be a useful tool for controlling cancer stem cells self-renewal, and therefore control patient relapse. Conclusions: We demonstrate that it is possible to interfere with the self-renewal capacity of cancer stem cells, induce anoikis in vivo, and reduce resistance against Docetaxel treatment in cancer patient cells in vitro culture. We have also demonstrated that this PEDF modified protein produces a significant decrease in cancer stem cell markers. All these properties make this protein a potential application in clinical cancer therapies via co-administration with chemotherapy for relapse cancer treatment.

Download Full-text

Therapeutic resistance and tumor-initiation: Molecular pathways involved in breast cancer stem cell self-renewal

Journal of Clinical Oncology ◽

10.1200/jco.2007.25.18_suppl.528 ◽

2007 ◽

Vol 25 (18_suppl) ◽

pp. 528-528 ◽

Cited By ~ 1

Author(s):

J. C. Chang ◽

X. Li ◽

H. Wong ◽

C. Creighton ◽

S. G. Hilsenbeck ◽

...

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Stem Cell ◽

Residual Disease ◽

Molecular Pathways ◽

Stem Cell Markers ◽

Tumor Initiation ◽

Self Renewal

528 Background: Recent evidence supports the existance of a rare subpopulation of ‘cancer stem cells‘ (CSCs) which is chemoresistant and capable of self-renewal and tumor-initiation, resulting in relapse and metastases. We hypothesized that residual breast tumors after conventional chemotherapy (CTx) are enriched for CSCs bearing CD44+/CD24- markers, and show increased self-renewal as demonstrated by mammosphere (MS) forming assays. Molecular pathways like Notch, Wnt, and the polycomb family that regulate normal mammary self-renewal may be in aberrant in CSCs. Methods: Paired breast cancer biopsies from 35 patients were obtained before and after 12 weeks of neoadjuvant CTx (docetaxel 100 mg/m2 or Adriamycin/Cytoxan 60/600 mg/m2, 4 cycles, q3weeks), digested by collagenase, stained with CD24/CD44/lineage antibodies, and analyzed by flow cytometry. MS assays were performed to measure self-renewal ability. Gene expression, using the Affymetrix U133 GeneChip platform, of cancer cells bearing CD44+/CD24- markers vs. all other sorted cells, and between secondary cancer MS vs. the primary bulk invasive cancers were analyzed. Results: CD44+/CD24- cells increased from a median of 4.8% to 14.8% after CTx (p<0.005). Increased self-renewal was demonstrated by an increase in MS capacity after CTx (p=0.03), with a positive correlation between the number of CD44+/24- cells and MS assays (R=0.8, p<0.05). Common molecular pathways shared by CD44+/CD24- cells and MS show increased expression in normal self-renewal pathways - polycomb family (PCGF5), Notch (MAML2), FOXP1, and BBX. In addition, genes governing alternative splicing were increased, including a non-coding RNA (MALAT1) of unknown function, and RNA splicing factors (SFRS3, SFRS21P, SFRS4). Conclusions: Our results with an increase in cells bearing stem cell markers, and increased MS formation of residual tumors provide the first strong clinical evidence for the existance of therapy-resistant cancer stem cells. Post-transcriptional regulation may play a crucial role in modifying gene function involved in cancer stem cell self-renewal. Clinical trials targeting these newly identified pathways may eradicate residual disease and improved cure rates for many breast cancer patients. [Table: see text]

Download Full-text

The effect of BMI-1 inhibition on brain cancer stem cells.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.e13543 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. e13543-e13543

Author(s):

Monal Mehta ◽

Atif J. Khan ◽

Hatem E. Sabaawy ◽

Bruce George Haffty

Keyword(s):

Stem Cells ◽

Cell Death ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cell Lines ◽

Brain Cancer ◽

Insertion Site ◽

Stem Cell Markers ◽

Primary Cells ◽

Self Renewal

e13543 Background: Glioblastoma (GBM) is the most frequent and deadly brain cancer. Despite tolerance doses of radiation, control of tumor growth within the brain remains a formidable failure. Since the identification of brain cancer stem cells (BCSCs), efforts are underway to target the pathways regulating these cells. The role of Bmi-1 (B-cell specific MMLV insertion site-1), a polycomb member of chromatin-remodeling complex, in BCSCs self-renewal was elucidated. Here we utilize shRNA targeting or pharmacological inhibition of Bmi-1 in GBM cell lines and primary cells as a radiosensitizer to examine the effects of combination therapy on cell death and BCSCs differentiation. Methods: Cells were pre-treated with a Bmi-1 inhibitor before being irradiated. Serial neurosphere assay, a measure of self-renewal potential, was employed to study the effects of radiation, Bmi-1 inhibition, or the combination on BCSCs. The efficacy of this combination on cell death was assessed with MTT and clonogenic assays. Next, the abilities of the inhibitor and radiation to induce differentiation in GBM cell lines and primary cells were quantified. Further, by utilizing a novel zebrafish orthotropic xenograft model, small molecules targeting Bmi-1 and other BCSC pathways can be identified, and used to predict response to combination therapies. Results: Targeting of Bmi-1 in combination with radiation, specifically as a radiosensitizer, induced significant cell death in GBM cells, and was five-fold more effective than radiation only. Importantly, the neurosphere forming ability of BCSCs was severely compromised when the cells were treated with the combination, indicating a potent effect on the stem cell constituency. These effects may be due to loss of BCSC self-renewal potential, increased differentiation, and/or apoptosis as cells treated with the combination exhibited decreased expression of neural stem cell markers and abnormal phenotypes compared to single treatment. Conclusions: Targeting of Bmi-1 may eliminate the subpopulation of radioresistant BCSCs. Bmi-1 inhibition when combined with radiotherapy might provide an effective therapy for GBM patients specifically through its effect on BCSCs by affecting their survival, proliferation, and stem cell features.

Download Full-text

Breast cancer stem cells expressing different stem cell markers exhibit distinct biological characteristics

Molecular Medicine Reports ◽

10.3892/mmr.2016.5899 ◽

2016 ◽

Vol 14 (6) ◽

pp. 4991-4998 ◽

Cited By ~ 24

Author(s):

Jun Shao ◽

Wei Fan ◽

Biao Ma ◽

Yiping Wu

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Biological Characteristics ◽

Stem Cell Markers ◽

Breast Cancer Stem Cells ◽

Cell Markers

Download Full-text

A Systematic Review to Clarify the Prognostic Values of CD44 and CD44+CD24- Phenotype in Triple-Negative Breast Cancer Patients: Lessons Learned and The Road Ahead

Frontiers in Oncology ◽

10.3389/fonc.2021.689839 ◽

2021 ◽

Vol 11 ◽

Author(s):

Mahdi Abdoli Shadbad ◽

Negar Hosseinkhani ◽

Zahra Asadzadeh ◽

Afshin Derakhshani ◽

Noora Karim Ahangar ◽

...

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Stem Cell ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Cell Phenotype ◽

Stem Cell Markers ◽

Advanced Tumor Stage

As a unique population of tumor bulk, cancer stem cells have been implicated in tumor relapse and chemoresistance in triple-negative breast cancer (TNBC). Therefore, understanding the phenotype of cancer stem cells can pave the way for introducing novel molecular targeted therapies for treating TNBC patients. Preclinical studies have identified CD44+CD24-/low as a cancer stem cell phenotype; however, clinical studies have reported seemingly controversial results regarding the prognostic values of CD44 and CD44+CD24-/low phenotype in TNBC patients. To critically review the clinicopathological significance and prognostic values of CD44 and CD44+CD24-/low phenotype in TNBC patients, the Scopus, Embase, PubMed, and Web of Science databases were systematically searched to obtain the relevant records published before 20 October 2020. Based on nine included studies, CD44 and CD44+CD24-/low phenotype are associated with inferior prognosis in TNBC patients. Moreover, these cancer stem cell markers have been associated with advanced tumor stage, tumor size, higher tumor grade, tumor metastasis, and lymphatic involvement in TNBC patients. Our evidence has also indicated that, unlike the treatment-naïve TNBC patients, the tumoral cells of chemoradiotherapy-treated TNBC patients can upregulate the CD44+CD24-/low phenotype and establish an inverse association with androgen receptor (AR), leading to the inferior prognosis of affected patients. In summary, CD44 and CD44+CD24-/low phenotype can be utilized to determine TNBC patients’ prognosis in the pathology department as a routine practice, and targeting these phenotypes can substantially improve the prognosis of TNBC patients.

Download Full-text

miR-142-3p attenuates breast cancer stem cell characteristics and decreases radioresistance in vitro

Tumor Biology ◽

10.1177/1010428318791887 ◽

2018 ◽

Vol 40 (8) ◽

pp. 101042831879188 ◽

Cited By ~ 26

Author(s):

Fabian M Troschel ◽

Nicolas Böhly ◽

Katrin Borrmann ◽

Timo Braun ◽

Alexander Schwickert ◽

...

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

Cancer Stem Cell ◽

Quantitative Polymerase Chain Reaction ◽

Breast Cancer Stem Cell ◽

Stem Cell Markers ◽

Western Blots ◽

Mammosphere Formation

Effectively targeting cancer stem cells, a subpopulation of tumorigenic, aggressive, and radioresistant cells, holds therapeutic promise. However, the effects of the microRNA miR-142-3p, a small endogenous regulator of gene expression on breast cancer stem cells, have not been investigated. This study identifies the influence of miR-142-3p on mammary stemness properties and breast cancer radioresistance to establish its role in this setting. miR-142-3p precursor transfection was performed in MDA-MB-468, HCC1806, and MCF-7 cells, and stem cell markers CD44, CD133, ALDH1 activity and mammosphere formation were measured. β-catenin, the canonical wnt signaling effector protein, was quantified by Western blots and cell fluorescence assays both in miR-142-3p–overexpressing and anti–miR-142-3p–treated cells. Radiation response was investigated by colony formation assays. Levels of BRCA1, BRCA2, and Bod1 in miR-142-3p–overexpressing cells as well as expression of miR-142-3p, Bod1, KLF4, and Oct4 in sorted CD44+/CD24–/low cells were determined by quantitative polymerase chain reaction. miR-142-3p overexpression resulted in a strong decline in breast cancer stem cell characteristics with a decrease in CD44, CD133, ALDH1, Bod1, BRCA2, and mammosphere formation as well as reduced survival after irradiation. miR-142-3p expression was strongly reduced in sorted CD44+/CD24–/low stem cells, while Bod1, Oct4, and KLF4 were overexpressed. β-catenin levels strongly decreased after miR-142-3p overexpression, but not after anti–miR-142-3p treatment. We conclude that miR-142-3p downregulates cancer stem cell characteristics and radioresistance in breast cancer, mediated by a reduced role of β-catenin in miR-142-3p–overexpressing cells. miR-142-3p might therefore help to target cancer stem cells.

Download Full-text

FTY720 Inhibits Expansion of Breast Cancer Stem Cells via PP2A Activation

International Journal of Molecular Sciences ◽

10.3390/ijms22147259 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7259

Author(s):

Naoya Hirata ◽

Shigeru Yamada ◽

Shota Yanagida ◽

Atsushi Ono ◽

Yasunari Kanda

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Cancer Stem Cells ◽

Drug Repositioning ◽

Immunosuppressive Agent ◽

Stem Cell Markers ◽

Breast Cscs ◽

Therapeutic Drugs ◽

A Minor

Growing evidence suggests that breast cancer originates from a minor population of cancer cells termed cancer stem cells (CSCs), which can be identified by aldehyde dehydrogenase (ALDH) activity-based flow cytometry analysis. However, novel therapeutic drugs for the eradication of CSCs have not been discovered yet. Recently, drug repositioning, which finds new medical uses from existing drugs, has been expected to facilitate drug discovery. We have previously reported that sphingosine kinase 1 (SphK1) induced proliferation of breast CSCs. In the present study, we focused on the immunosuppressive agent FTY720 (also known as fingolimod or Gilenya), since FTY720 is known to be an inhibitor of SphK1.We found that FTY720 blocked both proliferation of ALDH-positive cells and formation of mammospheres. In addition, we showed that FTY720 reduced the expression of stem cell markers such as Oct3/4, Sox2 and Nanog via upregulation of protein phosphatase 2A (PP2A). These results suggest that FTY720 is an effective drug for breast CSCs in vitro.

Download Full-text

High Frequency of Tumor Propagating Cells in Fusion-Positive Rhabdomyosarcoma

Genes ◽

10.3390/genes12091373 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1373

Author(s):

Melanie Generali ◽

Sampoorna Satheesha ◽

Peter K. Bode ◽

Debora Wanner ◽

Beat W. Schäfer ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Cancer Stem Cells ◽

High Frequency ◽

Cell Clone ◽

Hierarchical Organization ◽

Stem Cell Markers ◽

Worse Prognosis

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children. Fusion-positive RMS (FPRMS), expressing the PAX3/7-FOXO1, has a worse prognosis compared to the more common fusion-negative RMS (FNRMS). Although several studies reported hierarchical organization for FNRMS with the identification of cancer stem cells, the cellular organization of FPRMS is not yet clear. In this study we investigated the expression of key stem cell markers, developed a sphere assay, and investigated the seven most common FPRMS cell lines for subpopulations of tumor propagating cancer stem-like cells, also called cancer stem cells (CSCs). Moreover, loss- and gain-of-functions of the stem cell genes SOX2, OCT4, and NANOG were investigated in the same cells. Single-cell clonal analysis was performed in vitro as well as in vivo. We found that no stable CSC subpopulation could be enriched in FPRMS. Unlike depletion of PAX3-FOXO1, neither overexpression nor siRNA-mediated downregulation of SOX2, OCT4, and NANOG affected physiology of RMS cells. Every single subclone-derived cell clone initiated tumor growth in mice, despite displaying considerable heterogeneity in gene expression. FPRMS appears to contain a high frequency of tumor propagating stem-like cells, which could explain their higher propensity for metastasis and relapse. Their dependency on PAX3-FOXO1 activity reinforces the importance of the fusion protein as the key therapeutic target.

Download Full-text

ID: 1063 Isolation and characterization of female germline stem cell derived from porcine ovary

Biomedical Research and Therapy ◽

10.15419/bmrat.v4is.337 ◽

2017 ◽

Vol 4 (S) ◽

pp. 145

Author(s):

Nguyen Huy Hoang ◽

Nguyen Thi Bao Tran ◽

Nguyen Van Thuan ◽

Bui Hong Thuy

Keyword(s):

Stem Cells ◽

Stem Cell ◽

In Vitro Culture ◽

Germline Stem Cell ◽

Stem Cell Markers ◽

Significant Finding ◽

Germline Stem Cells ◽

Isolation And Characterization ◽

Female Germline

One of the most significant finding in stem cell area in the early 21st century is the founding of female germline stem cells (FGSCs). Establishment of FGSCs allowed new possibilities for the use of them in biotechnology and medicine. Hence, the purpose of this study was to establish, characterize the porcine female germline stem cells (pFGSCs) from porcine ovary. The result revealed the success in establishing pFGSCs from ovarian tissue. Most of the pFGSCs were round shape after in vitro culture, forming groups of cells that cluster around the ovarian cells colonies. Immunofluorescent analysis of pFGSCs showed that these cells expressed germ cell and stem cell markers such as: Vasa, Stella, c-kit and Oct4. After several weeks in in vitro culture, pFGSCs increased in number without the loss of proliferative potential. Our results suggested that pFGSCs isolated from adult mammalian ovary, under appropriate conditions, could undergo proliferation.

Download Full-text