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Olszewska AM, Zmijewski MA. Genomic and non-genomic action of vitamin D on ion channels - Targeting mitochondria. Mitochondrion 2024; 77:101891. [PMID: 38692383 DOI: 10.1016/j.mito.2024.101891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/26/2024] [Accepted: 04/28/2024] [Indexed: 05/03/2024]
Abstract
Recent studies revealed that mitochondria are not only a place of vitamin D3 metabolism but also direct or indirect targets of its activities. This review summarizes current knowledge on the regulation of ion channels from plasma and mitochondrial membranes by the active form of vitamin D3 (1,25(OH)2D3). 1,25(OH)2D3, is a naturally occurring hormone with pleiotropic activities; implicated in the modulation of cell differentiation, and proliferation and in the prevention of various diseases, including cancer. Many experimental data indicate that 1,25(OH)2D3 deficiency induces ionic remodeling and 1,25(OH)2D3 regulates the activity of multiple ion channels. There are two main theories on how 1,25(OH)2D3 can modify the function of ion channels. First, describes the involvement of genomic pathways of response to 1,25(OH)2D3 in the regulation of the expression of the genes encoding channels, their auxiliary subunits, or additional regulators. Interestingly, intracellular ion channels, like mitochondrial, are encoded by the same genes as plasma membrane channels. Therefore, the comprehensive genomic regulation of the channels from these two different cellular compartments we analyzed using a bioinformatic approach. The second theory explores non-genomic pathways of vitamin D3 activities. It was shown, that 1,25(OH)2D3 indirectly regulates enzymes that impact ion channels, change membrane physical properties, or directly bind to channel proteins. In this article, the involvement of genomic and non-genomic pathways regulated by 1,25(OH)2D3 in the modulation of the levels and activity of plasma membrane and mitochondrial ion channels was investigated by an extensive review of the literature and analysis of the transcriptomic data using bioinformatics.
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Affiliation(s)
- A M Olszewska
- Department of Histology, Medical University of Gdansk, 1a Debinki, 80-211 Gdansk, Poland
| | - M A Zmijewski
- Department of Histology, Medical University of Gdansk, 1a Debinki, 80-211 Gdansk, Poland.
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Xia C, Liu C, Ren S, Cai Y, Zhang Q, Xia C. Potassium channels, tumorigenesis and targeted drugs. Biomed Pharmacother 2023; 162:114673. [PMID: 37031494 DOI: 10.1016/j.biopha.2023.114673] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 04/11/2023] Open
Abstract
Potassium channels play an important role in human physiological function. Recently, various molecular mechanisms have implicated abnormal functioning of potassium channels in the proliferation, migration, invasion, apoptosis, and cancer stem cell phenotype formation. Potassium channels also mediate the association of tumor cells with the tumor microenvironment. Meanwhile, potassium channels are important targets for cancer chemotherapy. A variety of drugs exert anti-cancer effects by modulating potassium channels in tumor cells. Therefore, there is a need to understand how potassium channels participate in tumor development and progression, which could reveal new, novel targets for cancer diagnosis and treatment. This review summarizes the roles of voltage-gated potassium channels, calcium-activated potassium channels, inwardly rectifying potassium channels, and two-pore domain potassium channels in tumorigenesis and the underlying mechanism of potassium channel-targeted drugs. Therefore, the study lays the foundation for rational and effective drug design and individualized clinical therapeutics.
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Affiliation(s)
- Cong Xia
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province 116023, China
| | - Can Liu
- Affiliated Foshan Maternity and Child Healthcare Hospital, Southern Medical University, Foshan, Guangdong Province 528099, China; School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong Province 510515, China
| | - Shuangyi Ren
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province 116023, China
| | - Yantao Cai
- Affiliated Foshan Maternity and Child Healthcare Hospital, Southern Medical University, Foshan, Guangdong Province 528099, China
| | - Qianshi Zhang
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province 116023, China.
| | - Chenglai Xia
- Affiliated Foshan Maternity and Child Healthcare Hospital, Southern Medical University, Foshan, Guangdong Province 528099, China; School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong Province 510515, China.
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BOLAT H, ERDOĞAN A. Relationship of blood 25-hydroxy vitamin D level with fibrocystic breast disease and breast density. CUKUROVA MEDICAL JOURNAL 2022. [DOI: 10.17826/cumj.1016601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Olszewska AM, Sieradzan AK, Bednarczyk P, Szewczyk A, Żmijewski MA. Mitochondrial potassium channels: A novel calcitriol target. Cell Mol Biol Lett 2022; 27:3. [PMID: 34979905 PMCID: PMC8903690 DOI: 10.1186/s11658-021-00299-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/20/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Calcitriol (an active metabolite of vitamin D) modulates the expression of hundreds of human genes by activation of the vitamin D nuclear receptor (VDR). However, VDR-mediated transcriptional modulation does not fully explain various phenotypic effects of calcitriol. Recently a fast non-genomic response to vitamin D has been described, and it seems that mitochondria are one of the targets of calcitriol. These non-classical calcitriol targets open up a new area of research with potential clinical applications. The goal of our study was to ascertain whether calcitriol can modulate mitochondrial function through regulation of the potassium channels present in the inner mitochondrial membrane. METHODS The effects of calcitriol on the potassium ion current were measured using the patch-clamp method modified for the inner mitochondrial membrane. Molecular docking experiments were conducted in the Autodock4 program. Additionally, changes in gene expression were investigated by qPCR, and transcription factor binding sites were analyzed in the CiiiDER program. RESULTS For the first time, our results indicate that calcitriol directly affects the activity of the mitochondrial large-conductance Ca2+-regulated potassium channel (mitoBKCa) from the human astrocytoma (U-87 MG) cell line but not the mitochondrial calcium-independent two-pore domain potassium channel (mitoTASK-3) from human keratinocytes (HaCaT). The open probability of the mitoBKCa channel in high calcium conditions decreased after calcitriol treatment and the opposite effect was observed in low calcium conditions. Moreover, using the AutoDock4 program we predicted the binding poses of calcitriol to the calcium-bound BKCa channel and identified amino acids interacting with the calcitriol molecule. Additionally, we found that calcitriol influences the expression of genes encoding potassium channels. Such a dual, genomic and non-genomic action explains the pleiotropic activity of calcitriol. CONCLUSIONS Calcitriol can regulate the mitochondrial large-conductance calcium-regulated potassium channel. Our data open a new chapter in the study of non-genomic responses to vitamin D with potential implications for mitochondrial bioenergetics and cytoprotective mechanisms.
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Affiliation(s)
- Anna M Olszewska
- Department of Histology, Medical University of Gdańsk, 1a Dębinki, 80-211, Gdańsk, Poland
| | - Adam K Sieradzan
- Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdańsk, Poland
| | - Piotr Bednarczyk
- Department of Physics and Biophysics, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Adam Szewczyk
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093, Warsaw, Poland
| | - Michał A Żmijewski
- Department of Histology, Medical University of Gdańsk, 1a Dębinki, 80-211, Gdańsk, Poland.
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Abstract
The relationship between solar ultraviolet radiation and the risk of breast cancer is conflicting. The purpose of our study was to quantitatively assess the relationship between solar ultraviolet radiation and breast cancer risk and to analyze related factors such as age and sunscreen use.Articles indexed in PubMed and Embase and published between January 2005 and March 2020 were searched for relevant keywords. The relative risk was calculated using random-effect or fixed-effect models in the meta-analysis and dose-response meta-analysis, which were conducted according to the Meta-Analyses of Observational Studies in Epidemiology reporting guidelines. Sensitivity analyses for heterogeneity and publication bias were evaluated.Six studies were eligible for inclusion in the meta-analysis, and three of these were included in the dose-response analysis. We found a correlation between exposure to solar ultraviolet radiation and breast cancer risk (relative risk: 0.70, 95% confidence interval: 0.65, 0.75). We also found a linear dose-response relationship between the exposure and breast cancer risk (relative risk: 0.86, 95% confidence interval: 0.81, 0.91) in women over 40. Not tanning and covering the limbs were associated with breast cancer risk, but sunscreen use was not.Exposure to solar ultraviolet radiation is negatively correlated with breast cancer risk, and the association is linear in women over 40. This is the first dose-response meta-analysis on the topic, and the influence of factors such as estrogen receptor status, occupational exposure, and ethnicity requires in-depth study.
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Capatina AL, Lagos D, Brackenbury WJ. Targeting Ion Channels for Cancer Treatment: Current Progress and Future Challenges. Rev Physiol Biochem Pharmacol 2020; 183:1-43. [PMID: 32865696 DOI: 10.1007/112_2020_46] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ion channels are key regulators of cancer cell pathophysiology. They contribute to a variety of processes such as maintenance of cellular osmolarity and membrane potential, motility (via interactions with the cytoskeleton), invasion, signal transduction, transcriptional activity and cell cycle progression, leading to tumour progression and metastasis. Ion channels thus represent promising targets for cancer therapy. Ion channels are attractive targets because many of them are expressed at the plasma membrane and a broad range of existing inhibitors are already in clinical use for other indications. However, many of the ion channels identified in cancer cells are also active in healthy normal cells, so there is a risk that certain blockers may have off-target effects on normal physiological function. This review describes recent research advances into ion channel inhibitors as anticancer therapeutics. A growing body of evidence suggests that a range of existing and novel Na+, K+, Ca2+ and Cl- channel inhibitors may be effective for suppressing cancer cell proliferation, migration and invasion, as well as enhancing apoptosis, leading to suppression of tumour growth and metastasis, either alone or in combination with standard-of-care therapies. The majority of evidence to date is based on preclinical in vitro and in vivo studies, although there are several examples of ion channel-targeting strategies now reaching early phase clinical trials. Given the strong links between ion channel function and regulation of tumour growth, metastasis and chemotherapy resistance, it is likely that further work in this area will facilitate the development of new therapeutic approaches which will reach the clinic in the future.
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Affiliation(s)
| | - Dimitris Lagos
- Hull York Medical School, York, UK
- York Biomedical Research Institute, University of York, York, UK
| | - William J Brackenbury
- Department of Biology, University of York, York, UK.
- York Biomedical Research Institute, University of York, York, UK.
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Kito H, Morihiro H, Sakakibara Y, Endo K, Kajikuri J, Suzuki T, Ohya S. Downregulation of the Ca 2+-activated K + channel K Ca3.1 in mouse preosteoblast cells treated with vitamin D receptor agonist. Am J Physiol Cell Physiol 2020; 319:C345-C358. [PMID: 32520608 DOI: 10.1152/ajpcell.00587.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The maturity of osteoblasts by proliferation and differentiation in preosteoblasts is essential for maintaining bone homeostasis. The beneficial effects of vitamin D on bone homeostasis in mammals have been demonstrated experimentally and clinically. However, the direct actions of vitamin D on preosteoblasts remain to be fully elucidated. In this study, we found that the functional activity of intermediate-conductance Ca2+-activated K+ channels (KCa3.1) positively regulated cell proliferation in MC3T3-E1 cells derived from mouse preosteoblasts by enhancing intracellular Ca2+ signaling. We examined the effects of treatment with vitamin D receptor (VDR) agonist on the expression and activity of KCa3.1 by real-time PCR examination, Western blotting, Ca2+ imaging, and patch clamp analyses in mouse MC3T3-E1 cells. Following the downregulation of KCa3.1 transcriptional modulators such as Fra-1 and HDAC2, KCa3.1 activity was suppressed in MC3T3-E1 cells treated with VDR agonists. Furthermore, application of the KCa3.1 activator DCEBIO attenuated the VDR agonist-evoked suppression of cell proliferation rate. These findings suggest that a decrease in KCa3.1 activity is involved in the suppression of cell proliferation rate in VDR agonist-treated preosteoblasts. Therefore, KCa3.1 plays an important role in bone formation by promoting osteoblastic proliferation under physiological conditions.
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Affiliation(s)
- Hiroaki Kito
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Haruka Morihiro
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Yuka Sakakibara
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Kyoko Endo
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Junko Kajikuri
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Takayoshi Suzuki
- Department of Complex Molecular Chemistry, The Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan
| | - Susumu Ohya
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
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Mohr CJ, Schroth W, Mürdter TE, Gross D, Maier S, Stegen B, Dragoi A, Steudel FA, Stehling S, Hoppe R, Madden S, Ruth P, Huber SM, Brauch H, Lukowski R. Subunits of BK channels promote breast cancer development and modulate responses to endocrine treatment in preclinical models. Br J Pharmacol 2020; 179:2906-2924. [PMID: 32468618 DOI: 10.1111/bph.15147] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 03/20/2020] [Accepted: 05/13/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Pore-forming α subunits of the voltage- and Ca2+ -activated K+ channel with large conductance (BKα) promote malignant phenotypes of breast tumour cells. Auxiliary subunits such as the leucine-rich repeat containing 26 (LRRC26) protein, also termed BKγ1, may be required to permit activation of BK currents at a depolarized resting membrane potential that frequently occur in non-excitable tumour cells. EXPERIMENTAL APPROACH Anti-tumour effects of BKα loss were investigated in breast tumour-bearing MMTV-PyMT transgenic BKα knockout (KO) mice, primary MMTV-PyMT cell cultures, and in a syngeneic transplantation model of breast cancer derived from these cells. The therapeutic relevance of BK channels in the context of endocrine treatment was assessed in human breast cancer cell lines expressing either low (MCF-7) or high (MDA-MB-453) levels of BKα and BKγ1, as well as in BKα-negative MDA-MB-157. KEY RESULTS BKα promoted breast cancer onset and overall survival in preclinical models. Conversely, lack of BKα and/or knockdown of BKγ1 attenuated proliferation of murine and human breast cancer cells in vitro. At low concentrations, tamoxifen and its major active metabolites stimulated proliferation of BKα/γ1-positive breast cancer cells, independent of the genomic signalling controlled by the oestrogen receptor. Finally, tamoxifen increased the relative survival time of BKα KO but not of wild-type tumour cell recipient mice. CONCLUSION AND IMPLICATIONS Breast cancer initiation, progression, and tamoxifen sensitivity depend on functional BK channels thereby providing a rationale for the future exploration of the oncogenic actions of BK channels in clinical outcomes with anti-oestrogen therapy.
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Affiliation(s)
- Corinna J Mohr
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany.,Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Werner Schroth
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Thomas E Mürdter
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Dominic Gross
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
| | - Selina Maier
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany.,Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Benjamin Stegen
- Department of Radiation Oncology, University of Tuebingen, Tuebingen, Germany
| | - Alice Dragoi
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
| | - Friederike A Steudel
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
| | - Severine Stehling
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
| | - Reiner Hoppe
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Stephen Madden
- RCSI Division of Population Health Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
| | - Stephan M Huber
- Department of Radiation Oncology, University of Tuebingen, Tuebingen, Germany
| | - Hiltrud Brauch
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany.,German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.,iFIT-Cluster of Excellence, University of Tuebingen, Tuebingen, Germany
| | - Robert Lukowski
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tuebingen, Tuebingen, Germany
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Restrepo-Angulo I, Bañuelos C, Camacho J. Ion Channel Regulation by Sex Steroid Hormones and Vitamin D in Cancer: A Potential Opportunity for Cancer Diagnosis and Therapy. Front Pharmacol 2020; 11:152. [PMID: 32210800 PMCID: PMC7076584 DOI: 10.3389/fphar.2020.00152] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 02/05/2020] [Indexed: 12/24/2022] Open
Abstract
Many ion channels are involved in tumor development, promoting cancer cell proliferation, migration, invasion, and survival. Accordingly, some of them have been suggested as tumor markers and novel targets for cancer therapy. Some sex steroid hormones (SSH), including estrogens and androgens, favor cancer progression. Meanwhile, other steroid hormones like vitamin D may have anticancer properties. SSH and vitamin D modulate the expression of a number of ion channels in cancer cells from hormone-sensitive tissues, including breast, ovary, prostate, and cervix. Moreover, rapid effects of SSH may be mediated by their direct action on membrane ion channels. Here, we reviewed the SSH and vitamin D regulation of ion channels involved in cancer, and analyzed the potential molecular pathways implicated. In addition, we described the potential clinical use of ion channels in cancer diagnosis and therapy, taking advantage of their regulation by SSH and vitamin D. Since SSH are considered risk factors for different types of cancer, and ion channels play important roles in tumor progression, the regulation of ion channels by SSH and vitamin D may represent a potential opportunity for early cancer diagnosis and therapeutic approaches in SSH and vitamin D sensitive tumors.
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Affiliation(s)
- Iván Restrepo-Angulo
- Department of Pharmacology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Cecilia Bañuelos
- Transdisciplinary Program on Science, Technology and Society, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Javier Camacho
- Department of Pharmacology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
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Cell Cycle Regulation by Ca 2+-Activated K⁺ (BK) Channels Modulators in SH-SY5Y Neuroblastoma Cells. Int J Mol Sci 2018; 19:ijms19082442. [PMID: 30126198 PMCID: PMC6121591 DOI: 10.3390/ijms19082442] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/02/2018] [Accepted: 08/13/2018] [Indexed: 12/28/2022] Open
Abstract
The effects of Ca2+-activated K+ (BK) channel modulation by Paxilline (PAX) (10−7–10−4 M), Iberiotoxin (IbTX) (0.1–1 × 10−6 M) and Resveratrol (RESV) (1–2 × 10−4 M) on cell cycle and proliferation, AKT1pSer473 phosphorylation, cell diameter, and BK currents were investigated in SH-SY5Y cells using Operetta-high-content-Imaging-System, ELISA-assay, impedentiometric counting method and patch-clamp technique, respectively. IbTX (4 × 10−7 M), PAX (5 × 10−5 M) and RESV (10−4 M) caused a maximal decrease of the outward K+ current at +30 mV (Vm) of −38.3 ± 10%, −31.9 ± 9% and −43 ± 8%, respectively, which was not reversible following washout and cell depolarization. After 6h of incubation, the drugs concentration dependently reduced proliferation. A maximal reduction of cell proliferation, respectively of −60 ± 8% for RESV (2 × 10−4 M) (IC50 = 1.50 × 10−4 M), −65 ± 6% for IbTX (10−6 M) (IC50 = 5 × 10−7 M), −97 ± 6% for PAX (1 × 10−4 M) (IC50 = 1.06 × 10−5 M) and AKT1pser473 dephosphorylation was observed. PAX induced a G1/G2 accumulation and contraction of the S-phase, reducing the nuclear area and cell diameter. IbTX induced G1 contraction and G2 accumulation reducing diameter. RESV induced G2 accumulation and S contraction reducing diameter. These drugs share common actions leading to a block of the surface membrane BK channels with cell depolarization and calcium influx, AKT1pser473 dephosphorylation by calcium-dependent phosphatase, accumulation in the G2 phase, and a reduction of diameter and proliferation. In addition, the PAX action against nuclear membrane BK channels potentiates its antiproliferative effects with early apoptosis.
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Khatun A, Shimozawa M, Kito H, Kawaguchi M, Fujimoto M, Ri M, Kajikuri J, Niwa S, Fujii M, Ohya S. Transcriptional Repression and Protein Degradation of the Ca 2+-Activated K + Channel K Ca1.1 by Androgen Receptor Inhibition in Human Breast Cancer Cells. Front Physiol 2018; 9:312. [PMID: 29713287 PMCID: PMC5911984 DOI: 10.3389/fphys.2018.00312] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 03/14/2018] [Indexed: 01/14/2023] Open
Abstract
The large-conductance Ca2+-activated K+ channel KCa1.1 plays an important role in the promotion of breast cancer cell proliferation and metastasis. The androgen receptor (AR) is proposed as a therapeutic target for AR-positive advanced triple-negative breast cancer. We herein investigated the effects of a treatment with antiandrogens on the functional activity, activation kinetics, transcriptional expression, and protein degradation of KCa1.1 in human breast cancer MDA-MB-453 cells using real-time PCR, Western blotting, voltage-sensitive dye imaging, and whole-cell patch clamp recording. A treatment with the antiandrogen bicalutamide or enzalutamide for 48 h significantly suppressed (1) depolarization responses induced by paxilline (PAX), a specific KCa1.1 blocker and (2) PAX-sensitive outward currents induced by the depolarizing voltage step. The expression levels of KCa1.1 transcripts and proteins were significantly decreased in MDA-MB-453 cells, and the protein degradation of KCa1.1 mainly contributed to reductions in KCa1.1 activity. Among the eight regulatory β and γ subunits, LRRC26 alone was expressed at high levels in MDA-MB-453 cells and primary and metastatic breast cancer tissues, whereas no significant changes were observed in the expression levels of LRRC26 and activation kinetics of PAX-sensitive outward currents in MDA-MB-453 cells by the treatment with antiandrogens. The treatment with antiandrogens up-regulated the expression of the ubiquitin E3 ligases, FBW7, MDM2, and MDM4 in MDA-MB-453 cells, and the protein degradation of KCa1.1 was significantly inhibited by the respective siRNA-mediated blockade of FBW7 and MDM2. Based on these results, we concluded that KCa1.1 is an androgen-responsive gene in AR-positive breast cancer cells, and its down-regulation through enhancements in its protein degradation by FBW7 and/or MDM2 may contribute, at least in part, to the antiproliferative and antimetastatic effects of antiandrogens in breast cancer cells.
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Affiliation(s)
- Anowara Khatun
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Motoki Shimozawa
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Hiroaki Kito
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Mayu Kawaguchi
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Mayu Fujimoto
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Moe Ri
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Junko Kajikuri
- Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Satomi Niwa
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Masanori Fujii
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Susumu Ohya
- Division of Pathological Sciences, Department of Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan.,Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
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Pandolfi F, Franza L, Mandolini C, Conti P. Immune Modulation by Vitamin D: Special Emphasis on Its Role in Prevention and Treatment of Cancer. Clin Ther 2017; 39:884-893. [PMID: 28431765 DOI: 10.1016/j.clinthera.2017.03.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/06/2017] [Accepted: 03/12/2017] [Indexed: 12/14/2022]
Abstract
PURPOSE Vitamin D has been known to be involved in mineral and bone homeostasis for many years. In the past its main use was in treating osteoporosis and rickets. In recent years it was found that vitamin D is an immune-modulating agent and may also have a role in several diseases, including autoimmune diseases. The immune-modulating effects appear to be mediated by vitamin D interaction with the vitamin D receptor (VDR) that has transcriptional effects and is expressed on various cell types, especially those of the immune system. Immunologic and rheumatologic diseases were the first to be studied, but at the moment the spotlight is on the interactions between tumor cells and vitamin D. This review focuses on four forms of cancer that apparently benefit from a vitamin D supplementation during treatment: prostate, breast, and colorectal cancers and melanoma. Several studies reported that differences exist between white and black patients, which we discuss in the review. METHODS We systematically searched PubMed for studies published in English. The search terms included vitamin D, cancer, breast, colorectal, prostate, and melanoma. FINDINGS AND IMPLICATIONS Our findings show that vitamin D has the potential to become a valid coadjuvant in the treatment of cancer.
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Affiliation(s)
| | - Laura Franza
- Internal Medicine Catholic University, Rome, Italy
| | | | - Pio Conti
- Postgraduate Medical School, Chieti University, Chieti, Italy.
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