Publications by authors named "Ahmed Ahidouch"

28 Publications

  • Page 1 of 1

Ion Channel Signature in Healthy Pancreas and Pancreatic Ductal Adenocarcinoma.

Front Pharmacol 2020 16;11:568993. Epub 2020 Oct 16.

Laboratory of Cellular and Molecular Physiology, UR-4667, University of Picardie Jules Verne, Amiens, France.

Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer-related deaths in United States and Europe. It is predicted that PDAC will become the second leading cause of cancer-related deaths during the next decades. The development of PDAC is not well understood, however, studies have shown that dysregulated exocrine pancreatic fluid secretion can contribute to pathologies of exocrine pancreas, including PDAC. The major roles of healthy exocrine pancreatic tissue are secretion of enzymes and bicarbonate rich fluid, where ion channels participate to fine-tune these biological processes. It is well known that ion channels located in the plasma membrane regulate multiple cellular functions and are involved in the communication between extracellular events and intracellular signaling pathways and can function as signal transducers themselves. Hereby, they contribute to maintain resting membrane potential, electrical signaling in excitable cells, and ion homeostasis. Despite their contribution to basic cellular processes, ion channels are also involved in the malignant transformation from a normal to a malignant phenotype. Aberrant expression and activity of ion channels have an impact on essentially all hallmarks of cancer defined as; uncontrolled proliferation, evasion of apoptosis, sustained angiogenesis and promotion of invasion and migration. Research indicates that certain ion channels are involved in the aberrant tumor growth and metastatic processes of PDAC. The purpose of this review is to summarize the important expression, localization, and function of ion channels in normal exocrine pancreatic tissue and how they are involved in PDAC progression and development. As ion channels are suggested to be potential targets of treatment they are furthermore suggested to be biomarkers of different cancers. Therefore, we describe the importance of ion channels in PDAC as markers of diagnosis and clinical factors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphar.2020.568993DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7596276PMC
October 2020

Effects of the Tumor Environment on Ion Channels: Implication for Breast Cancer Progression.

Rev Physiol Biochem Pharmacol 2020 Aug 7. Epub 2020 Aug 7.

Laboratory of Cellular and Molecular Physiology, UR UPJV 4667, University of Picardie Jules Verne, Amiens, France.

In recent years, it has been shown that breast cancer consists not only of neoplastic cells, but also of significant alterations in the surrounding stroma or tumor microenvironment. These alterations are now recognized as a critical element for breast cancer development and progression, as well as potential therapeutic targets. Furthermore, there is no doubt that ion channels are deregulated in breast cancer and some of which are prognostic markers of clinical outcome. Their dysregulation is also associated with aberrant signaling pathways. The number of published data on ion channels modifications by the microenvironment has significantly increased last years. Here, we summarize the state of the art on the cross talk between the tumor microenvironment and ion channels, in particular collagen 1, EGF, TGF-β, ATP, hypoxia, and pH, on the development and progression of breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/112_2020_19DOI Listing
August 2020

Roles for Ca and K channels in cancer cells exposed to the hypoxic tumour microenvironment.

Biochim Biophys Acta Mol Cell Res 2020 04 10;1867(4):118644. Epub 2020 Jan 10.

Université de Picardie Jules Verne, UFR des Sciences, Laboratoire de Physiologie Cellulaire et Moléculaire (EA 4667), Amiens, France. Electronic address:

For twenty years, ion channels have been studied in cancer progression. Several information have been collected about their involvement in cancer cellular processes like cell proliferation, motility and their participation in tumour progression using in-vivo models. Tumour microenvironment is currently the focus of many researches and the highlighting of the relationship between cancer cells and surrounding elements, is expanding. One of the major physic-chemical parameter involved in tumour progression is the hypoxia conditions observed in solid cancer. Due to their position on the cell membrane, ion channels are good candidates to transduce or to be modulated by environmental modifications. Until now, few reports have been interested in the modification of ion channel activities or expression in this context, compared to other pathological situations such as ischemia reperfusion. The aim of our review is to summarize the current knowledge about the calcium and potassium channels properties in the context of hypoxia in tumours. This review could pave the way to orientate new studies around this exciting field to obtain new potential therapeutic approaches.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbamcr.2020.118644DOI Listing
April 2020

sp -Iminosugar α-glucosidase inhibitor 1-C-octyl-2-oxa-3-oxocastanospermine specifically affected breast cancer cell migration through Stim1, β1-integrin, and FAK signaling pathways.

J Cell Physiol 2017 Dec 25;232(12):3631-3640. Epub 2017 Apr 25.

Laboratory of Cellular and Molecular Physiology (EA 4667), SFR CAP-SANTE (FED 4132), UFR of Sciences, Amiens, France.

Aberrant glycosylation changes on many glycoproteins are often related to cancer progression and metastasis. sp -Iminosugar-type castanospermine analogues, inhibitors of α-glucosidases, have been reported to exhibit antitumor activity. However, their effects on cell migration and the underlying molecular mechanism are not fully understood. Here, we investigated the effect of the pseudo-C-octyl glycoside 2-oxa-3-oxocastanospermine derivatives (CO-OCS) on breast cancer cells (MCF-7 and MDA-MB-231 cells), and MCF-10A mammary normal cell lines. We showed that CO-OCS treatment results in the drastic decrease of breast cancer cell migration without affecting cell proliferation. Furthermore, CO-OCS significantly reduced both the expression of β1-integrin, which is a crucial interacting partner of Focal Adhesion Kinase (FAK), and the phosphorylation rates of FAK and ERK1/2. CO-OCS also drastically reduced Ca entry through Store Operated Channels (SOC). Orai1 and Stim1, two N-glycosylated proteins, are involved in Store-Operated Calcium Entry (SOCE), and are essential for breast tumor cell migration. Our results showed that CO-OCS decreased the expression, at the protein level, of Stim1 without affecting that of Orai1. Moreover, cell migration and SOCE were attenuated by CO-OCS as well as when Stim1 was silenced. In contrast, in MCF-10A cells, CO-OCS slightly reduced cell migration, but was without effect on gene expression of Stim1, Orai1, β1-integrin, or FAK and ERK1/2 activation. Our results provide strong evidence for a significant effect of CO-OCS on breast cancer cell migration and support that this effect was associated with β1-integrin, Stim1, and FAK signaling pathways.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.25832DOI Listing
December 2017

Orai3 is a predictive marker of metastasis and survival in resectable lung adenocarcinoma.

Oncotarget 2016 Dec;7(49):81588-81597

Laboratory of Cellular and Molecular Physiology, LPCM: EA 4667, SFR CAP-SANTE (FED 4231), UFR of Sciences, Amiens, France.

Orai3 channel has emerged as important player in malignant transformation. Indeed, its expression is increased in cancer and favors cell proliferation and survival by permitting calcium influx. In this study, Orai3 was overexpressed in lung adenocarcinoma as compared to their matched non-tumour samples and was associated with tumoural aggressiveness. Moreover, its expression was associated with estrogen receptor alpha (ERα) expression and visceral pleural invasion in multivariate analysis. Furthermore, both the overall survival (OS) median and the metastasis free survival (MFS) median of tumors with high Orai3 expression were lower than in low Orai3 expression regardless of cancer stage (35.01 months vs. 51.11 months for OS and 46.01 months vs. 62.04 months for MFS). In conclusion, Orai3 protein level constitutes an independent prognostic marker in lung adenocarcinoma, and a novel prognostic marker that could help selecting the patients with worst prognosis to be treated with adjuvant chemotherapy in resectable stage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.13149DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5348414PMC
December 2016

Functional cooperation between KCa3.1 and TRPC1 channels in human breast cancer: Role in cell proliferation and patient prognosis.

Oncotarget 2016 Jun;7(24):36419-36435

University of Picardie Jules Verne, UFR of Sciences, EA4667 Laboratory of Cell and Molecular Physiology, SFR CAP-SANTE (FED 4231), Amiens, France.

Intracellular Ca2+ levels are important regulators of cell cycle and proliferation. We, and others, have previously reported the role of KCa3.1 (KCNN4) channels in regulating the membrane potential and the Ca2+ entry in association with cell proliferation. However, the relevance of KC3.1 channels in cancer prognosis as well as the molecular mechanism of Ca2+ entry triggered by their activation remain undetermined. Here, we show that RNAi-mediated knockdown of KCa3.1 and/or TRPC1 leads to a significant decrease in cell proliferation due to cell cycle arrest in the G1 phase. These results are consistent with the observed upregulation of both channels in synchronized cells at the end of G1 phase. Additionally, knockdown of TRPC1 suppressed the Ca2+ entry induced by 1-EBIO-mediated KCa3.1 activation, suggesting a functional cooperation between TRPC1 and KCa3.1 in the regulation of Ca2+ entry, possibly within lipid raft microdomains where these two channels seem to co-localize. We also show significant correlations between KCa3.1 mRNA expression and poor patient prognosis and unfavorable clinical breast cancer parameters by mining large datasets in the public domain. Together, these results highlight the importance of KCa3.1 in regulating the proliferative mechanisms in breast cancer cells as well as in providing a promising novel target in prognosis and therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.9261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5095010PMC
June 2016

Kv10.1 K(+) channel: from physiology to cancer.

Pflugers Arch 2016 05 8;468(5):751-62. Epub 2016 Jan 8.

Oncophysiology Group, Max Planck Institute of Experimental Medicine, Hermann-Rein-Straße 3, 37075, Göttingen, Germany.

K(+) ions play a major role in many cellular processes. The deregulation of K(+) signaling is associated with a variety of diseases including cancer. Ether-à-go-go-1 (Eag1, Kv10.1, KCNH1) is a member of the voltage-activated potassium channel family and was the first K(+) channel to be associated with oncogenesis and tumor development. Interestingly, in healthy tissue, Kv10.1 is only detected in the central nervous system, where it is involved in the regulation of excitability under repeated stimulation. Kv10.1 is in contrast robustly expressed in over 70 % human tumors, where its expression seems to be controlled by key regulators of proliferation and survival such as p53 and E2F1, often altered in cancer. Otherwise, Kv10.1 is involved in cell proliferation, survival, angiogenesis, migration, and invasion. This review aims to provide a comprehensive overview of the current status of research on the role of Kv10.1 channel in physiopathology. Focus is placed on biophysical and pharmacological properties of Kv10.1 channel, as well as its cycling, trafficking, and its role in the neuron and cancer. The possible mechanisms by which Kv10.1 channel affects tumor cell migration and survival in breast cancer and its regulation by extracellular proteins are discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00424-015-1784-3DOI Listing
May 2016

DNA methylation of channel-related genes in cancers.

Biochim Biophys Acta 2015 Oct 20;1848(10 Pt B):2621-8. Epub 2015 Feb 20.

UFR Sciences, EA 4667, Laboratory of Cell and Molecular Physiology, University of Picardie Jules Verne, SFR CAP-SANTE (FED 4231), Amiens, France; Department of Biology, Faculty of Sciences, Ibn Zohr University, Agadir Morocco.

DNA methylation at CpG sites is an epigenetic mechanism that regulates cellular gene expression. In cancer cells, aberrant methylation is correlated with the abnormalities in expression of genes that are known to be involved in the particular characteristics of cancer cells such as proliferation, apoptosis, migration or invasion. During the past 30 years, accumulating data have definitely convinced the scientific community that ion channels are involved in cancerogenesis and cancer properties. As they are situated at the cell surface, they might be prime targets in the development of new therapeutic strategies besides their potential use as prognostic factors. Despite the progress in our understanding of the remodeling of ion channels in cancer cells, the molecular mechanisms underlying their over- or down-expression remained enigmatic. In this review, we aimed to summarize the available data on gene promoter methylation of ion channels and to investigate their clinical significance as novel biomarkers in cancer. This article is part of a Special Issue entitled: Membrane channels and transporters in cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbamem.2015.02.015DOI Listing
October 2015

New castanospermine glycoside analogues inhibit breast cancer cell proliferation and induce apoptosis without affecting normal cells.

PLoS One 2013 4;8(10):e76411. Epub 2013 Oct 4.

Laboratory of Cellular and Molecular Physiology (EA 4667), SFR CAP-SANTE (FED 4132), UFR of Sciences, UPJV, Amiens, France.

sp²-Iminosugar-type castanospermine analogues have been shown to exhibit anti-tumor activity. However, their effects on cell proliferation and apoptosis and the molecular mechanism at play are not fully understood. Here, we investigated the effect of two representatives, namely the pseudo-S- and C-octyl glycoside 2-oxa-3-oxocastanospermine derivatives SO-OCS and CO-OCS, on MCF-7 and MDA-MB-231 breast cancer and MCF-10A mammary normal cell lines. We found that SO-OCS and CO-OCS inhibited breast cancer cell viability in a concentration- and time-dependent manner. This effect is specific to breast cancer cells as both molecules had no impact on normal MCF-10A cell proliferation. Both drugs induced a cell cycle arrest. CO-OCS arrested cell cycle at G1 and G2/M in MCF-7 and MDA-MB-231 cells respectively. In MCF-7 cells, the G1 arrest is associated with a reduction of CDK4 (cyclin-dependent kinase 4), cyclin D1 and cyclin E expression, pRb phosphorylation, and an overexpression of p21(Waf1/Cip1). In MDA-MB-231 cells, CO-OCS reduced CDK1 but not cyclin B1 expression. SO-OCS accumulated cells in G2/M in both cell lines and this blockade was accompanied by a decrease of CDK1, but not cyclin B1 expression. Furthermore, both drugs induced apoptosis as demonstrated by the increased percentage of annexin V positive cells and Bax/Bcl-2 ratio. Interestingly, in normal MCF-10A cells the two drugs failed to modify cell proliferation, cell cycle progression, cyclins, or CDKs expression. These results demonstrate that the effect of CO-OCS and SO-OCS is triggered by both cell cycle arrest and apoptosis, suggesting that these castanospermine analogues may constitute potential anti-cancer agents against breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0076411PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3790671PMC
May 2014

Orai3 constitutes a native store-operated calcium entry that regulates non small cell lung adenocarcinoma cell proliferation.

PLoS One 2013 13;8(9):e72889. Epub 2013 Sep 13.

Laboratory of Cellular and Molecular Physiology, LPCM: EA 4667, SFR CAP-SANTE (FED 4231), UFR of Sciences, Amiens, France.

Orai channels have been associated with cell proliferation, survival and metastasis in several cancers. The present study investigates the expression and the role of Orai3 in cell proliferation in non-small cell lung cancer (NSCLC). We show that Orai3 is over-expressed in cancer tissues as compared to the non-tumoral ones. Furthermore, Orai3 staining is stronger in high grade tumors. Pharmacological inhibition or knockdown of Orai3 significantly reduced store operated calcium entry (SOCE), inhibited cell proliferation and arrested cells of two NSCLC cell lines in G0/G1 phase. These effects were concomitant with a down-regulation of cyclin D1, cyclin E, CDK4 and CDK2 expression. Moreover, Orai3 silencing decreased Akt phosphorylation levels. In conclusion, Orai3 constitutes a native SOCE pathway in NSCLC that controls cell proliferation and cell cycle progression likely via Akt pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0072889PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772818PMC
June 2014

K(+) channels and cell cycle progression in tumor cells.

Front Physiol 2013 20;4:220. Epub 2013 Aug 20.

Laboratory of Cellular and Molecular Physiology EA4667, SFR CAP-SANTE FED 4231, UFR Sciences, University of Picardie Jules Verne Amiens, France.

K(+) ions play a major role in many cellular processes. The deregulation of K(+) signaling is associated with a variety of diseases such as hypertension, atherosclerosis, or diabetes. K(+) ions are important for setting the membrane potential, the driving force for Ca(2+) influx, and regulate volume of growing cells. Moreover, it is increasingly recognized that K(+) channels control cell proliferation through a novel signaling mechanisms triggered and modulated independently of ion fluxes. In cancer, aberrant expression, regulation and/or sublocalization of K(+) channels can alter the downstream signals that converge on the cell cycle machinery. Various K(+) channels are involved in cell cycle progression and are needed only at particular stages of the cell cycle. Consistent with this idea, the expression of Eag1 and HERG channels fluctuate along the cell cycle. Despite of acquired knowledge, our understanding of K(+) channels functioning in cancer cells requires further studies. These include identifying the molecular mechanisms controlling the cell cycle machinery. By understanding how K(+) channels regulate cell cycle progression in cancer cells, we will gain insights into how cancer cells subvert the need for K(+) signal and its downstream targets to proliferate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2013.00220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747328PMC
August 2013

ORAI3 silencing alters cell proliferation and cell cycle progression via c-myc pathway in breast cancer cells.

Biochim Biophys Acta 2013 Mar 22;1833(3):752-60. Epub 2012 Dec 22.

University of Picardie Jules Verne, UFR of Sciences, Laboratory of Cellular and Molecular Physiology EA 4667, SFR CAP-SANTE, Amiens, France.

Members of the Orai family are highly selective calcium ion channels that play an important role in store-operated calcium entry. Among the three known Orai isoforms, Orai3 has gained increased attention, notably for its emerging role in cancer. We recently demonstrated that Orai3 channels are over-expressed in breast cancer (BC) biopsies, and involved specifically in proliferation, cell cycle progression and survival of MCF-7 BC cells. Here, we investigate the downstream signaling mechanisms affected by Orai3 silencing, leading to the subsequent functional impact specifically seen in MCF-7 cancer cells. We report a correlation between Orai3 and c-myc expression in tumor tissues and in the MCF-7 cancer cell line by demonstrating that Orai3 down-regulation reduces both expression and activity of the proto-oncogene c-myc. This is likely mediated through the MAP Kinase pathway, as we observed decreased pERK1/2 levels and cell-cycle arrest in G1 phase after Orai3 silencing. Our results provide strong evidence that the c-myc proto-oncogene is influenced by the store-operated calcium entry channel Orai3 through the MAP kinase pathway. This connection provides new clues in the downstream mechanism linking Orai3 channels and proliferation, cell cycle progression and survival of MCF-7 BC cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbamcr.2012.12.009DOI Listing
March 2013

TRP channels: diagnostic markers and therapeutic targets for breast cancer?

Trends Mol Med 2013 Feb 17;19(2):117-24. Epub 2012 Dec 17.

University of Picardie Jules Verne, UFR Sciences, EA4667 Laboratory of Cell and Molecular Physiology, SFR CAP-SANTE, Amiens, France.

Breast cancer is the most frequently occurring cancer in women and has the highest rate of mortality. Ion channels such as the transient receptor potential (TRP) channels could play a critical role in the development and progression of cancer. Although these channels are frequently and abundantly expressed in many tumors, their expression, activity, and roles in the context of breast cancer remain poorly understood. This review summarizes our current knowledge regarding TRP channels expressed in human breast tissue, primary human breast epithelial cells, and cell lines, the functional role of TRP channels during breast cancer cell growth and migration, as well as their relationship with clinical and pathological features.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.molmed.2012.11.004DOI Listing
February 2013

[TRP calcium channel and breast cancer: expression, role and correlation with clinical parameters].

Bull Cancer 2012 Jun;99(6):655-64

Université de Picardie Jules-Verne, laboratoire de physiologie cellulaire et moléculaire, UFR des sciences, JE 2530, 33, rue Saint-Leu, 80039 Amiens, France.

Breast cancer (BC) has the highest incidence rate in women in industrialized countries. Statistically, it is estimated that one out of 10 women will develop BC during her life. Evidence is accumulating for the role of ion channels in the development of cancer. Most studied ion channels in BC are K(+) channels, which are involved in cell proliferation, cell cycle progression and cell migration, and Na(+) channels, which correlate with invasiveness. Emerging studies demonstrated the role of Ca(2+) signaling in cancer cell proliferation, survival and migration. Recent findings demonstrated that the expression and/or activity of the transient receptor potential (TRP) channels are altered in several cancers. Among the TRP families, TRPC (canonical or classical), TRPM (melastatin) and TRPV (vanilloid) are related to malignant growth and cancer progression. Although these channels are frequently and abundantly expressed in many tumors, their specific expression, activity and roles in BC are still poorly understood. The expression of TRP channels has also been proposed as a tool for diagnosis, prognosis and/or therapeutic issues of several diseases. In cancer, TRPV6 and TRPM8 have been proposed as tumor progression markers of prostate cancer outcome and TRPC6 as a novel therapeutic target for esophageal carcinoma. Interestingly high levels of TRPC3 expression correlate with a favorable prognosis in patients with lung adenocarcinoma. Our team has recently reported the expression and role of TRPC1, TRPC6, TRPM7, TRPM8 and TRPV6 in BC cell lines and primary cultures. We have also investigated TRP expression and their clinical significance in human breast adenocarcinoma and we suggest that TRP channels are new potential BC markers. Indeed TRPC1 and TRPM8 may be considered as good prognosis markers of well-differentiated tumors, TRPM7 as a proliferative marker of poorly differentiated tumors and TRPV6 as a prognosis marker of aggressive cancers. In this review, we summarize the data reported to date regarding the changes in TRP expression associated with BC. We also discuss the importance of TRP channels in BC cells proliferation and migration and their interest as new BC markers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1684/bdc.2012.1595DOI Listing
June 2012

High expression of transient receptor potential channels in human breast cancer epithelial cells and tissues: correlation with pathological parameters.

Cell Physiol Biochem 2011 15;28(5):813-22. Epub 2011 Dec 15.

Laboratoire de Physiologie Cellulaire, JE 2530, UFR Sciences, Université de Picardie Jules Verne, Amiens, France.

Background: Transient Receptor Potential (TRP) channels are expressed in many solid tumors. However, their expression in breast cancer remains largely unknown. Here, we investigated the profile expression of 13 TRP channels in human breast ductal adenocarcinoma (hBDA) and performed a correlation between their overexpression and pathological parameters.

Methods: The TRP channels expression was determined by RT-PCR in hBDA tissue, in human breast cancer epithelial (hBCE) primary culture and in MCF-7 cell line. The TRP protein level was evaluated by immunohistochemistry in hBDA tissue samples of 59 patients.

Results: TRPC1, TRPC6, TRPM7, TRPM8, and TRPV6 channels were overexpressed in hBDA compared to the adjacent non-tumoral tissue. Most interestingly, TRPC1, TRPM7 and TRPM8 expression strongly correlated with proliferative parameters (SBR grade, Ki67 proliferation index, and tumor size), and TRPV6 was mainly overexpressed in the invasive breast cancer cells. Using laser capture microdissection, we found that TRPV6 expression was higher in invasive areas, compared to the corresponding non-invasive ones. Moreover, TRPV6 silencing inhibited MDA-MB-231 migration and invasion, and MCF-7 migration.

Conclusion: TRP channels are aberrantly expressed in hBDA, hBCE primary cultures, and cell lines, and associated with pathological parameters. The high expression of TRP channels in tumors suggests the potential of these channels for diagnostic, prognosis and/or therapeutic approaches in human breast ductal adenocarcinoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000335795DOI Listing
April 2012

Intermediate conductance Ca2+ activated K+ channels are expressed and functional in breast adenocarcinomas: correlation with tumour grade and metastasis status.

Histol Histopathol 2010 10;25(10):1247-55

LPCM JE 2530, UPJV, Amiens, France.

K+ channels are key molecules in the progression of several cancer types and are considered to be potential targets for cancer therapy. In this study, we investigated the intermediate- conductance Ca2+-activated K+ channels (hKCa3.1) expression in both breast carcinoma (BC) specimens and human breast cancer epithelial primary cell cultures (hBCE) using immuno-histochemistry (60 samples), quantitative Real-Time RT-PCR (30 samples) and Western blot assay (30 samples). We also looked at whether or not the expression of these channels is correlated with breast carcinomas grade tumours and metastasis status. Furthermore, we characterized the hKCa3.1 channel activity in hBCE cells by using the Whole Cell Patch Clamp Technique. We found that hKCa3.1 transcripts and proteins were expressed in both BC samples and hBCE cells. Clinicopathologic evaluation indicated a significant correlation between hKCa3.1-expression and tumour grade. hKCa3.1 mRNA and protein were more highly expressed in grade III tumours than in both grades I and II. However, the hKCa3.1 expression-increase according to grade was only observed in tumours with negative metastasis status. Moreover, the hKCa3.1 channels expressed in hBCE cells are functional. This was attested by patch-clamp recordings showing typical hKCa3.1-mediated currents in these cells. In conclusion, these data suggest that hKCa3.1 might contribute to breast tumour-progression and can serve as a useful prognostic marker for breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14670/HH-25.1247DOI Listing
October 2010

Down-regulation of Orai3 arrests cell-cycle progression and induces apoptosis in breast cancer cells but not in normal breast epithelial cells.

J Cell Physiol 2011 Feb;226(2):542-51

Laboratoire de Physiologie Cellulaire et Moléculaire, JE 2530: Canaux ioniques dans le Cancer du Sein, Faculté des Sciences, UPJV, Amiens, France.

Breast cancer (BC) is the leading cancer in the world in terms of incidence and mortality in women. However, the mechanism by which BC develops remains largely unknown. The increase in cytosolic free Ca(2+) can result in different physiological changes including cell growth and death. Orai isoforms are highly Ca(2+) selective channels. In the present study, we analyzed Orai3 expression in normal and cancerous breast tissue samples, and its role in MCF-7 BC and normal MCF-10A mammary epithelial cell lines. We found that the expression of Orai3 mRNAs was higher in BC tissues and MCF-7 cells than in normal tissues and MCF-10A cells. Down-regulation of Orai3 by siRNA inhibited MCF-7 cell proliferation and arrested cell cycle at G1 phase. This phenomenon is associated with a reduction in CDKs 4/2 (cyclin-dependent kinases) and cyclins E and D1 expression and an accumulation of p21(Waf1/Cip1) (a cyclin-dependent kinase inhibitor) and p53 (a tumor-suppressing protein). Orai3 was also involved in MCF-7 cell survival. Furthermore, Orai3 mediated Ca(2+) entry and contributed to intracellular calcium concentration ([Ca(2+)](i)). In MCF-10A cells, silencing Orai3 failed to modify [Ca(2+)](i), cell proliferation, cell-cycle progression, cyclins (D1, E), CDKs (4, 2), and p21(Waf1/Cip1) expression. Our results provide strong evidence for a significant effect of Orai3 on BC cell growth in vitro and show that this effect is associated with the induction of cell cycle and apoptosis resistance. Our study highlights a possible role of Orai3 as therapeutic target in BC therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcp.22363DOI Listing
February 2011

Synthesis of N-, S-, and C-glycoside castanospermine analogues with selective neutral alpha-glucosidase inhibitory activity as antitumour agents.

Chem Commun (Camb) 2010 Aug 15;46(29):5328-30. Epub 2010 Jun 15.

Instituto de Investigaciones Químicas, CSIC, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain.

sp(2)-Iminosugar-type castanospermine analogues bearing an alpha-configured N-, S-, or C-linked pseudoanomeric group have been designed as selective inhibitors of the neutral alpha-glucosidases involved in N-glycoprotein processing; evaluation in breast cancer cell growth indicated a significant antiproliferative potential that was dependent on the nature of the pseudoanomeric group.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c0cc00446dDOI Listing
August 2010

Intermediate Ca2+-sensitive K+ channels are necessary for prolactin-induced proliferation in breast cancer cells.

J Membr Biol 2010 Mar 23;234(1):47-56. Epub 2010 Feb 23.

Laboratoire de Physiologie Cellulaire et Moléculaire, Université de Picardie Jules Verne, 80000 Amiens, France.

Prolactin (PRL) is a polypeptidic hormone which acts both systemically and locally to cause lactation by interacting with the PRL receptor, a Janus kinase (JAK2)-coupled cytokine receptor family member. Several studies have reported that serum PRL level elevation is associated with an increased risk for breast cancer, and evidence has suggested that PRL is one actor in the pathogenesis and progression of this cancer. We previously reported the involvement of hIKCa1 in breast cell cycle progression and cell proliferation. However, mechanisms by which PRL cooperates with these channels to modulate breast epithelial cell proliferation remain unknown. Our results showed that, in the MCF-7 breast cancer cell line, PRL increased hIKCa1 current density. These channels were functional and regulated the resting membrane potential. The PRL effects were inhibited by TRAM-34 and clotrimazole, the most used hIKCa1 blockers. Moreover, PRL increased proliferation in a dose-dependent manner without overexpressing hIKCa1. To determine whether PRL-induced proliferation and hIKCa1 activity involved the JAK2 pathway, we used pharmacological JAK2 inhibitors (AG490 and JAK inhibitor I). Indeed, PRL-induced JAK2 phosphorylation was required for both cell proliferation and hIKCa1 activity. In the presence of either hIKCa1 blockers or siRNA-hIKCa1, PRL failed to increase cell proliferation and hIKCa1 activity. Taken together, our results demonstrate that PRL plays a role in breast cancer cell proliferation by increasing hIKCa1 activity through the JAK2 signaling pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00232-010-9238-5DOI Listing
March 2010

Extracellular signal-regulated kinases 1 and 2 and TRPC1 channels are required for calcium-sensing receptor-stimulated MCF-7 breast cancer cell proliferation.

Cell Physiol Biochem 2009 6;23(4-6):335-46. Epub 2009 May 6.

Laboratoire de Physiologie Cellulaire et Moléculaire, Faculté des Sciences, Université de Picardie Jules Verne, Amiens, France.

The calcium-sensing receptor (CaR), is a G protein-dependent receptor that responds to increments in extracellular Ca(2+) ([Ca(2+)](o)). We previously reported that an increase in [Ca(2+)](o) induced a release of intracellular calcium and Ca(2+) entry via store operated channels (SOCs). We also demonstrated that MCF-7 cells express Transient Receptor Potential canonical 1 (TRPC1) channels. Herein, we investigated CaR intracellular signaling pathways and examined the role of TRPC1 in CaR-induced cell proliferation, through the extracellular signal-regulated Kinases 1 & 2 (ERK1/2) pathways. Treatment by [Ca(2+)](o) increased both MCF-7 cell proliferation and TRPC1 expression. Both the [Ca(2+)](o) proliferative effect and TRPC1 protein levels were abolished by the ERK1/2 inhibitors. Moreover, [Ca(2+)](o) failed to increase cell proliferation either in the presence of CaR or TRPC1 siRNAs. Both [Ca(2+)](o) and the selective CaR activator spermine, elicited time and dose-dependent ERK1/2 phosphorylation. ERK1/2 phosphorylation was almost completely inhibited by treatment with the phospholipase C and the protein kinase C inhibitors. Treatment with 2-aminoethoxydiphenyl borate (2-APB), and SKF-96365 or by siTRPC1 diminished both [Ca(2+)](o)- and spermine-stimulated ERK1/2 phosphorylation. Moreover, down-regulation of TRPC1 by siRNA reduced the Ca(2+) entry induced by CaR activation. We conclude that the CaR activates ERK1/2 via a PLC/PKC-dependent pathway. Moreover, TRPC1 is required for the ERK1/2 phosphorylation, Ca(2+) entry and the CaR-proliferative effect.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000218179DOI Listing
August 2009

Activation of the calcium-sensing receptor by high calcium induced breast cancer cell proliferation and TRPC1 cation channel over-expression potentially through EGFR pathways.

Arch Biochem Biophys 2009 Jun 28;486(1):58-63. Epub 2009 Mar 28.

Laboratoire de Physiologie Cellulaire et Moléculaire, JE 2530 Canaux Ioniques dans le cancer du sein, Faculté des Sciences, 33 Rue St Leu 80039, Amiens, France.

The calcium sensing receptor (CaR) is a G-protein-coupled receptor that is activated by extracellular calcium ([Ca(2+)](o)). In MCF-7 human breast cancer cells, we previously reported that treatment with [Ca(2+)](o) for 24h leads to an over-expression of the Transient Receptor Potential Canonical 1 (TRPC1) cation channel and cell proliferation. Both involve the extracellular signal-regulated Kinases 1 & 2 (ERK1/2). MCF-7 also expressed epidermal growth factor receptor (EGFR) which is involved in cell proliferation through ERK1/2. Therefore, we investigated the cross-talk between CaR and EGFR in mediating ERK1/2 phosphorylation, TRPC1 over-expression and cell proliferation. Our data show that both high [Ca(2+)](o) and EGF phosphorylate ERK1/2. Furthermore, inhibition of EGFR kinase and matrix metalloproteinases (MMPs) reduced the overall effects mediated by [Ca(2+)](o) such as activation of ERK1/2, expression of TRPC1 and cell proliferation. They indicate the important role of the CaR-EGFR-ERK axis in transmitting mitogenic signals generated by high [Ca(2+)](o) in MCF-7 cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.abb.2009.03.010DOI Listing
June 2009

Expression of K+ channels in normal and cancerous human breast.

Histol Histopathol 2008 08;23(8):965-72

Laboratoire de Physiologie Cellulaire et Moléculaire, EA 2086, Faculté des Sciences, Amiens, France.

Potassium (K+) channels contribute to the regulation of cell proliferation and apoptosis and are also involved in tumor generation and malignant growth. Using immunohistochemical analysis, we investigated the expression of four K+ channels GIRK1 (G-Protein Inwardly Rectifying Potassium Channel 1), Ca2+-activated K channel (K Ca 1.1), voltage activated K+ channels (KV 1.1 and KV 1.3) and of the anti-apoptotic protein Bcl2 in normal and cancerous breast tissues and compared their expression with clinicopathological data. GIRK1 was overexpressed in carcinomatous tissues. In contrast, K V 1.1 and K V 1.3 were less expressed in cancerous tissue. The expression of Bcl-2 was similar in both tissues. As to the clinicopathological data, a correlation between K Ca 1.1 channel and estrogen receptor (ER) expression was observed. GIRK1 was overexpressed in breast carcinoma suggesting its involvement in proliferation and oncogenesis and its possible use as a putative pharmaceutical target. The correlation between K Ca 1.1 channel and ER suggests the involvement of this channel in proliferation. The loss of expression of the two channels K V 1.1 and K V 1.3 may correspond to their role in apoptosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14670/HH-23.965DOI Listing
August 2008

Expression of TRPC6 channels in human epithelial breast cancer cells.

BMC Cancer 2008 May 2;8:125. Epub 2008 May 2.

Laboratoire de Physiologie Cellulaire et Moléculaire, JE Canaux ioniques dans le cancer du sein, Faculté des Sciences, Université de Picardie Jules Verne, 33 Rue St Leu 80039, Amiens, France.

Background: TRP channels have been shown to be involved in tumour generation and malignant growth. However, the expression of these channels in breast cancer remains unclear. Here we studied the expression and function of endogenous TRPC6 channels in a breast cancer cell line (MCF-7), a human breast cancer epithelial primary culture (hBCE) and in normal and tumour breast tissues.

Methods: Molecular (Western blot and RT-PCR), and immunohistochemical techniques were used to investigate TRPC6 expression. To investigate the channel activity in both MCF-7 cells and hBCE we used electrophysiological technique (whole cell patch clamp configuration).

Results: A non selective cationic current was activated by the oleoyl-2-acetyl-sn-glycerol (OAG) in both hBCE and MCF-7 cells. OAG-inward current was inhibited by 2-APB, SK&F 96365 and La3+. TRPC6, but not TRPM7, was expressed both in hBCE and in MCF-7 cells. TRPC3 was only expressed in hBCE. Clinically, TRPC6 mRNA and protein were elevated in breast carcinoma specimens in comparison to normal breast tissue. Furthermore, we found that the overexpression of TRPC6 protein levels were not correlated with tumour grades, estrogen receptor expression or lymph node positive tumours.

Conclusion: Our results indicate that TRPC6 channels are strongly expressed and functional in breast cancer epithelial cells. Moreover, the overexpression of these channels appears without any correlation with tumour grade, ER expression and lymph node metastasis. Our findings support the idea that TRPC6 may have a role in breast carcinogenesis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1471-2407-8-125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2409351PMC
May 2008

Voltage-gated ion channels, new targets in anti-cancer research.

Recent Pat Anticancer Drug Discov 2007 Nov;2(3):189-202

Inserm, E 211, Nutrition Croissance Cancer, Tours, France; Université François-Rabelais de Tours, Tours, France.

Cancer is one of the leading causes of mortality in the world. This is a complex disease involving many steps with proper signalling pathways. Early detection and treatment of cancers have increased survival and improved clinical outcome. However, novel strategies based on new interesting targets are needed to improve the conventional treatments. A few years ago, it appeared that some particular transmembrane proteins, ion channels, may be involved in the development of the disease. Since then, their role in cancer cell properties such as proliferation, migration and invasion begins to be unravelled. These proteins have been widely studied in non cancerous cells as well as in pathologies involving excitable cells and thus, their pharmacology are quite well known. In this review, we summarize the present knowledge about the role of different ion channels in some aspects of the development of tumours, mainly proliferation, migration and invasion. A particular emphasis is done on promising new patents.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2174/157489207782497244DOI Listing
November 2007

K+ channel expression in human breast cancer cells: involvement in cell cycle regulation and carcinogenesis.

J Membr Biol 2008 Jan 3;221(1):1-6. Epub 2007 Dec 3.

Laboratoire de Physiologie Cellulaire et Moléculaire, Faculté des Sciences, Université Picardie Jules Verne, EA 2086, 33 rue Saint-leu, Amiens, France.

K+ channels are a most diverse class of ion channels in the plasma membrane and are distributed widely throughout a variety of cells including cancer cells. Evidence has been accumulating from fundamental studies indicating that tumour cells possess various types of K+ channels and that these K+ channels play important roles in regulating tumor cell proliferation, cell cycle progression and apoptosis. Moreover, a significant increase in K+ channel expression has been correlated with tumorigenesis, suggesting the possibility of using these proteins as transformation markers and perhaps reducing the tumor growth rate by selectively inhibiting their functional activity. Significant progress has been made in defining the properties of breast K+ channels, including their biophysical and pharmacological properties and distribution throughout different phases of the cell cycle in breast cell line MCF-7. This review aims to provide a comprehensive overview of the current state of research into K+ channels/currents in breast cancer cells. The possible mechanisms by which K+ channels affect tumor cell proliferation and cell cycle progression are discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00232-007-9080-6DOI Listing
January 2008

Calcium-sensing receptor stimulation induces nonselective cation channel activation in breast cancer cells.

J Membr Biol 2006 14;211(2):127-37. Epub 2006 Oct 14.

Laboratoire de Physiologie Cellulaire et Moléculaire, EA 2086, Faculté des Sciences, Université de Picardie Jules Verne, 33 rue Saint-leu, 80039, Amiens, France.

The calcium-sensing receptor (CaR) is expressed in epithelial ducts of both normal human breast and breast cancer tissue, as well as in the MCF-7 cell line as assessed by immunohistochemistry and Western blot analysis. However, to date, there are no data regarding the transduction pathways of CaR in breast cancer cells. In this study, we show that a CaR agonist, spermine, and increased extracellular Ca(2+) ([Ca(2+)](o)) sequentially activate two inward currents at -80 mV. The first was highly permeable to Ca(2+) and inhibited by 2-aminophenyl borate (2-APB). In contrast, the second was more sensitive to Na(+) and Li(+) than to Ca(2+) and insensitive to 2-APB. Furthermore, intracellular dialysis with high Mg(2+), flufenamic acid or amiloride perfusion was without any effect on the second current. Both currents were inhibited by La(3+). Calcium imaging recordings showed that both [Ca(2+)](o) and spermine induced an increase in intracellular calcium ([Ca(2+)](i)) and that removal of extracellular Ca(2+) or perfusion of 2-APB caused a decline in [Ca(2+)](i). It is well known that stimulation of CaR by an increase in [Ca(2+)](o) or with spermine is associated with activation of phospholipase C (PLC). Inhibition of PLC reduced the [Ca(2+)](o)-stimulated [Ca(2+)](i) increase. Lastly, reverse-transcriptase polymerase chain reaction showed that MCF-7 cells expressed canonical transient receptor potential (TRPCs) channels. Our results suggest that, in MCF-7 cells, CaR is functionally coupled to Ca(2+)-permeable cationic TRPCs, for which TRPC1 and TRPC6 are the most likely candidates for the highly selective Ca(2+) current. Moreover, the pharmacology of the second Na(+) current excludes the involvement of the more selective Na(+) transient receptor potential melastatin (TRPM4 and TRPM5) and the classical epithelial Na(+ )channels.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00232-006-0017-2DOI Listing
April 2007

Cell-cycle-dependent expression of the large Ca2+-activated K+ channels in breast cancer cells.

Biochem Biophys Res Commun 2004 Mar;316(1):244-51

Laboratoire de Physiologie Cellulaire, INSERM EMI 0228, SN3, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq Cédex, France.

In a previous work, we have reported that the ionic nature of the outward current recorded in MCF-7 cells was that of a K+ current. In this study, we have identified a Ca2+-activated K+ channel not yet described in MCF-7 human breast cancer cells. In cells arrested in the early G1 (depolarized cells), increasing [Ca2+]i induced both a shift in the I-V curve toward more negative potentials and an increase in current amplitude at negative and more at positive potential. Currents were inhibited by r-iberiotoxin (r-IbTX, 50 nM) and charybdotoxin (ChTX, 50 nM). These data indicate that human breast cancer cells express large-conductance Ca2+-activated K+ (BK) channels. BK current-density increased in cells synchronized at the end of G1, as compared with those in the early G1 phase. This increased current-density paralleled the enhancement in BK mRNA levels. Blocking BK channels with r-IbTX, ChTX or both induced a slight depolarization in cells arrested in the early G1, late G1, and S phases and accumulated cells in the S phase, but failed to induce cell proliferation. Thus, the expression of the BK channels was cell-cycle-dependent and seems to contribute more to the S phase than to the G1 phase. However, these K+ channels did not regulate the cell proliferation because of their minor role in the membrane potential.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2004.02.041DOI Listing
March 2004

Functional and molecular identification of intermediate-conductance Ca(2+)-activated K(+) channels in breast cancer cells: association with cell cycle progression.

Am J Physiol Cell Physiol 2004 Jul 25;287(1):C125-34. Epub 2004 Feb 25.

Laboratoire de Physiologie Cellulaire, Université des Sciences et Technologies de Lille, Cedex, France.

We have previously reported that the hEAG K(+) channels are responsible for the potential membrane hyperpolarization that induces human breast cancer cell progression into the G1 phase of the cell cycle. In the present study, we evaluate the role and functional expression of the intermediate-conductance Ca(2+)-activated K(+) channel, hIK1-like, in controlling cell cycle progression. Our results demonstrate that hIK1 current density increased in cells synchronized at the end of the G1 or S phase compared with those in the early G1 phase. This increased current density paralleled the enhancement in hIK1 mRNA levels and the highly negative membrane potential. Furthermore, in cells synchronized at the end of G1 or S phases, basal cytosolic Ca(2+) concentration ([Ca(2+)](i)) was also higher than in cells arrested in early G1. Blocking hIK1 channels with a specific blocker, clotrimazole, induced both membrane potential depolarization and a decrease in the [Ca(2+)](i) in cells arrested at the end of G1 and S phases but not in cells arrested early in the G1 phase. Blocking hIK1 with clotrimazole also induced cell proliferation inhibition but to a lesser degree than blocking hEAG with astemizole. The two drugs were essentially additive, inhibiting MCF-7 cell proliferation by 82% and arresting >90% of cells in the G1 phase. Thus, although the progression of MCF-7 cells through the early G1 phase is dependent on the activation of hEAG K(+) channels, when it comes to G1 and checkpoint G1/S transition, the membrane potential appears to be primarily dependent on the hIK1-activity level.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajpcell.00488.2003DOI Listing
July 2004