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Gu J, Ye Y, Sunil R, Zhan W, Yu R. Downregulation of lncRNA SATB2‑AS1 facilitates glioma cell proliferation by sponging miR‑671‑5p. Exp Ther Med 2023; 26:503. [PMID: 37822583 PMCID: PMC10562957 DOI: 10.3892/etm.2023.12202] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 07/28/2023] [Indexed: 10/13/2023] Open
Abstract
The antisense transcript of SATB2 protein (SATB2-AS1) is a novel long non-coding RNA (lncRNA) which is involved in the development of colorectal cancer, breast cancer and hepatocellular carcinoma. In the present study, it was aimed to investigate the consequent situation of SATB2-AS1 in tissue and cell lines of glioma. The expression of SATB2-AS1 in glioma cases was analyzed in The Cancer Genome Atlas datasets. The glycolytic metabolism was determined in glioma cells by detection of extracellular glucose level, oxygen consumption rate and extracellular acidification rate. Cell Counting Kit-8 assay and flow cytometry were used to assess cell proliferation and apoptosis in glioma cells. The interaction between SATB2-AS1 and microRNA (miR)-671-5p was verified by bioinformatic analysis, reverse transcription-quantitative PCR, dual luciferase reporter assay and RNA immunoprecipitation assay. The expression levels of the downstream targets of SATB2-AS1 were studied by western blotting. Results demonstrated that SATB2-AS1 was a downregulated lncRNA in low grade glioma and glioblastoma. Gain-of-function assay demonstrated that SATB2-AS1 inhibited cell proliferation, and glycolytic metabolism, while induced cell apoptosis in glioma cells. SATB2-AS1 sponged and suppressed the expression of an oncogenic miRNA miR-671-5p. By regulation of miR-671-5p, SATB2-AS1 upregulated cerebellar degeneration related protein 1 (CDR1) and Visinin-like 1 (VSNL1) expression in glioma cells. miR-671-5p overexpression partially reversed the antitumor effect of SATB2-AS1 in glioma. In conclusion, the current study demonstrated that there was a downregulation of SATB2-AS1 in glioma, and SATB2-AS1 regulated miR-671-5p/CDR1 axis and miR-671-5p/VSNL1 axis in glioma.
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Affiliation(s)
- Jia Gu
- Department of Neurosurgery, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, P.R. China
| | - Yongqing Ye
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, Jiangsu 221002, P.R. China
| | - Rauniyar Sunil
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, Jiangsu 221002, P.R. China
| | - Wenjian Zhan
- Department of Neurosurgery, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, P.R. China
| | - Rutong Yu
- Department of Neurosurgery, Nanjing Medical University, Nanjing, Jiangsu 211166, P.R. China
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, P.R. China
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Tage H, Yamaguchi K, Nakagawa S, Kasuga S, Takane K, Furukawa Y, Ikenoue T. Visinin-like 1, a novel target gene of the Wnt/β-catenin signaling pathway, is involved in apoptosis resistance in colorectal cancer. Cancer Med 2023. [PMID: 37096864 DOI: 10.1002/cam4.5970] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 03/14/2023] [Accepted: 04/07/2023] [Indexed: 04/26/2023] Open
Abstract
BACKGROUND Abnormal activation of Wnt/β-catenin signaling is associated with various aspects of cancer development. This study explored the roles of novel target genes of the Wnt/β-catenin signaling pathway in cancer cells. METHODS Using the haploid chronic myelogenous leukemia cell line HAP1, RNA sequencing (RNA-seq) was performed to identify genes whose expression was increased by APC disruption and reversed by β-catenin knockdown (KD). The regulatory mechanism and function of one of the candidate genes was investigated in colorectal cancer (CRC) cells. RESULTS In total, 64 candidate genes whose expression was regulated by Wnt/β-catenin signaling were identified. Of these candidate genes, the expression levels of six were reduced by β-catenin KD in HCT116 CRC cells in our previous microarray. One of these genes was Visinin-like 1 ( VSNL1 ), which belongs to the neuronal calcium-sensor gene family. The expression of VSNL1 was regulated by the β-catenin/TCF7L2 complex via two TCF7L2-binding elements in intron 1. VSNL1 KDinduced apoptosis in VSNL1-positive CRC cells. Additionally, forced expression of wild-type VSNL1, but not a myristoylation, Ca2+ -binding, or dimerization-defective mutant, suppressed the apoptosis induced by camptothecin and doxorubicin in VSNL1-negative CRC cells. CONCLUSION Our findings suggest that VSNL1 , a novel target gene of the Wnt/β-catenin signaling pathway, is associated with apoptosis resistance in CRC cells.
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Affiliation(s)
- Hiroki Tage
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Kiyoshi Yamaguchi
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Saya Nakagawa
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - So Kasuga
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Kiyoko Takane
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yoichi Furukawa
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Tsuneo Ikenoue
- Division of Clinical Genome Research, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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Zhang H, Weström S, Kappelin P, Virtanen M, Vahlquist A, Törmä H. Exploration of novel candidate genes involved in epidermal keratinocyte differentiation and skin barrier repair in man. Differentiation 2021; 119:19-27. [PMID: 34029921 DOI: 10.1016/j.diff.2021.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/11/2021] [Accepted: 04/27/2021] [Indexed: 12/26/2022]
Abstract
A proper skin barrier function requires constant formation of stratum corneum, i.e. the outermost layer of epidermis composed of terminally differentiated keratinocytes. The complex process of converting proliferative basal keratinocytes into corneocytes relies on programmed changes in the activity of many well-established genes. Much remains however to be investigated about this process, e.g. in conjunction with epidermal barrier defects due to genetic errors as in ichthyosis. To this end, we re-analyzed two sets of microarray-data comparing altered gene expression in differentiated vs. proliferating keratinocytes and in the skin of patients with autosomal recessive congenital ichthyosis (ARCI) vs. healthy controls, respectively. We thus identified 24 genes to be upregulated in both sets of array and not previously associated with keratinocyte differentiation. For 10 of these genes (AKR1B10, BLNK, ENDOU, GCNT4, GLTP, RHCG, SLC15A1, TMEM45B, TMEM86A and VSNL1), qPCR analysis confirmed the array results and subsequent immunostainings of normal epidermis showed superficial expression of several of the proteins. Furthermore, induction of keratinocyte differentiation using phorbol esters (PMA) resulted in increased expression of eight of the genes, whereas siRNA silencing of PPARδ, a transcription factor supporting differentiation, had the opposite effect. In summary, our results identify ten new candidate genes seemingly involved in human epidermal keratinocyte differentiation and possibly important for epidermal repair in a genetic skin disease characterized by barrier failure.
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Affiliation(s)
- Hanqian Zhang
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Simone Weström
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Per Kappelin
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Marie Virtanen
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Anders Vahlquist
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Hans Törmä
- Department of Medical Sciences/Dermatology, Uppsala University, SE-751 85, Uppsala, Sweden.
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Barbagallo D, Condorelli A, Ragusa M, Salito L, Sammito M, Banelli B, Caltabiano R, Barbagallo G, Zappalà A, Battaglia R, Cirnigliaro M, Lanzafame S, Vasquez E, Parenti R, Cicirata F, Di Pietro C, Romani M, Purrello M. Dysregulated miR-671-5p / CDR1-AS / CDR1 / VSNL1 axis is involved in glioblastoma multiforme. Oncotarget 2016; 7:4746-59. [PMID: 26683098 PMCID: PMC4826240 DOI: 10.18632/oncotarget.6621] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 11/14/2015] [Indexed: 01/04/2023] Open
Abstract
MiR-671-5p is encoded by a gene localized at 7q36.1, a region amplified in human glioblastoma multiforme (GBM), the most malignant brain cancer. To investigate whether expression of miR-671-5p were altered in GBM, we analyzed biopsies from a cohort of forty-five GBM patients and from five GBM cell lines. Our data show significant overexpression of miR-671-5p in both biopsies and cell lines. By exploiting specific miRNA mimics and inhibitors, we demonstrated that miR-671-5p overexpression significantly increases migration and to a less extent proliferation rates of GBM cells. Through a combined in silico and in vitro approach, we identified CDR1-AS, CDR1, VSNL1 as downstream miR-671-5p targets in GBM. Expression of these genes significantly decreased both in GBM biopsies and cell lines and negatively correlated with that of miR-671-5p. Based on our data, we propose that the axis miR-671-5p / CDR1-AS / CDR1 / VSNL1 is functionally altered in GBM cells and is involved in the modification of their biopathological profile.
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Affiliation(s)
- Davide Barbagallo
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Angelo Condorelli
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Marco Ragusa
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Loredana Salito
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Mariangela Sammito
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Barbara Banelli
- UOS Epigenetica dei Tumori, IRCCS A.O.U. San Martino-IST, Genova, Italy, EU
| | - Rosario Caltabiano
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Università di Catania, Catania, Italy, EU
| | - Giuseppe Barbagallo
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Università di Catania, Catania, Italy, EU
| | - Agata Zappalà
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Fisiologia, Università di Catania, Catania, Italy, EU
| | - Rosalia Battaglia
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Matilde Cirnigliaro
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Salvatore Lanzafame
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Università di Catania, Catania, Italy, EU
| | - Enrico Vasquez
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Università di Catania, Catania, Italy, EU
| | - Rosalba Parenti
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Fisiologia, Università di Catania, Catania, Italy, EU
| | - Federico Cicirata
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Fisiologia, Università di Catania, Catania, Italy, EU
| | - Cinzia Di Pietro
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
| | - Massimo Romani
- UOS Epigenetica dei Tumori, IRCCS A.O.U. San Martino-IST, Genova, Italy, EU
| | - Michele Purrello
- Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU
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Liebl MP, Kaya AM, Tenzer S, Mittenzwei R, Koziollek-Drechsler I, Schild H, Moosmann B, Behl C, Clement AM. Dimerization of visinin-like protein 1 is regulated by oxidative stress and calcium and is a pathological hallmark of amyotrophic lateral sclerosis. Free Radic Biol Med 2014; 72:41-54. [PMID: 24742816 DOI: 10.1016/j.freeradbiomed.2014.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 04/04/2014] [Accepted: 04/05/2014] [Indexed: 11/28/2022]
Abstract
Redox control of proteins that form disulfide bonds upon oxidative challenge is an emerging topic in the physiological and pathophysiological regulation of protein function. We have investigated the role of the neuronal calcium sensor protein visinin-like protein 1 (VILIP-1) as a novel redox sensor in a cellular system. We have found oxidative stress to trigger dimerization of VILIP-1 within a cellular environment and identified thioredoxin reductase as responsible for facilitating the remonomerization of the dimeric protein. Dimerization is modulated by calcium and not dependent on the myristoylation of VILIP-1. Furthermore, we show by site-directed mutagenesis that dimerization is exclusively mediated by Cys187. As a functional consequence, VILIP-1 dimerization modulates the sensitivity of cells to an oxidative challenge. We have investigated whether dimerization of VILIP-1 occurs in two different animal models of amyotrophic lateral sclerosis (ALS) and detected soluble VILIP-1 dimers to be significantly enriched in the spinal cord from phenotypic disease onset onwards. Moreover, VILIP-1 is part of the ALS-specific protein aggregates. We show for the first time that the C-terminus of VILIP-1, containing Cys187, might represent a novel redox-sensitive motif and that VILIP-1 dimerization and aggregation are hallmarks of ALS. This suggests that VILIP-1 dimers play a functional role in integrating the cytosolic calcium concentration and the oxidative status of the cell. Furthermore, a loss of VILIP-1 function owing to protein aggregation in ALS could be relevant in the pathophysiology of the disease.
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Affiliation(s)
- Martina P Liebl
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Ali M Kaya
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Stefan Tenzer
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Romy Mittenzwei
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Ingrid Koziollek-Drechsler
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Hansjörg Schild
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Bernd Moosmann
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Christian Behl
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Albrecht M Clement
- Institute for Pathobiochemistry, University Medical Center, Johannes Gutenberg University, D-55099 Mainz, Germany.
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6
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Enhanced UV-induced skin carcinogenesis in transgenic mice overexpressing proprotein convertases. Neoplasia 2013; 15:169-79. [PMID: 23441131 DOI: 10.1593/neo.121846] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 12/03/2012] [Accepted: 12/07/2012] [Indexed: 02/01/2023] Open
Abstract
The proprotein convertases (PCs) furin and PACE4 process numerous substrates involved in tumor growth, invasion, and metastasis. We have previously shown that PCs increase the susceptibility to chemical skin carcinogenesis. Because of the human relevancy of UV radiation in the etiopathogenesis of human skin cancer, we investigated whether or not transgenic mice overexpressing either furin alone or both furin and PACE4 show increased susceptibility to UV carcinogenesis. After backcrossing our previously described furin and PACE4 transgenic lines, targeted to the epidermis, into a SKH-1 background, we exposed both single and double transgenic mice to UV radiation for 34 weeks. The results showed an increase in squamous cell carcinoma (SCC) multiplicity of approximately 70% in the single furin transgenic mouse line SF47 (P < .002) and a 30% increase in the other single transgenic line SF49 when compared to wild-type (WT) SKH-1 mice. Interestingly, there was also an increase in the percentage of high histologic grade SCCs in the transgenic lines compared to the WT mice, i.e., WT = 9%, SF47 = 15%, and SF49 = 26% (P < .02). Targeting both furin and PACE4 to the epidermis in double transgenic mice did not have an additive effect on tumor incidence/multiplicity but did enhance the tumor histopathologic grade, i.e., a significant increase in higher grade SCCs was seen in the bigenic mouse line SPF47 (P < .02). Thus, we observed an increased susceptibility to UV in single furin transgenic mice that was not substantially enhanced in the double furin/PACE4 transgenic mice.
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7
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Transgenic overexpression of the proprotein convertase furin enhances skin tumor growth. Neoplasia 2012; 14:271-82. [PMID: 22577343 DOI: 10.1593/neo.12166] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 04/02/2012] [Accepted: 04/02/2012] [Indexed: 02/04/2023] Open
Abstract
Furin, one of the members of the family of proprotein convertases (PCs), ubiquitously expressed as a type I membrane-bound proteinase, activates several proteins that contribute to tumor progression. In vitro studies using cancer cell lines and clinical specimens demonstrated that furin processes important substrates such as insulin-like growth factor 1 receptor (IGF-1R) and transforming growth factor β, leading to increased tumor growth and progression. Despite the numerous studies associating furin with tumor development, its effects in preclinical models has not been comprehensively studied. In this study, we sought to determine the protumorigenic role of furin in vivo after a two-stage chemical carcinogenesis protocol in transgenic mice in which furin expression was targeted to the epidermal basal layer. We found that processing of the PC substrate IGF-1R and the proliferation rate of mouse epidermis was enhanced in transgenic mice when compared with their WT counterparts. Histopathologic diagnoses of the tumors demonstrated that furin transgenic mice (line F47) developed twice as many squamous carcinomas as the control, WT mice (P < .002). Similarly, tumors cells from transgenic mice were able to process PC substrates more efficiently than tumor cells from WT mice. Furthermore, furin expression resulted in a higher SCC volume in transgenic mice as well as an increase in the percentage of high-grade SCC, including poorly differentiated and spindle cell carcinomas. In conclusion, expression of furin in the basal layer of the epidermis increased tumor development and enhanced tumor growth, supporting the consideration of furin as a potential target for cancer treatment.
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Nejatbakhsh N, Feng ZP. Calcium binding protein-mediated regulation of voltage-gated calcium channels linked to human diseases. Acta Pharmacol Sin 2011; 32:741-8. [PMID: 21642945 DOI: 10.1038/aps.2011.64] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Calcium ion entry through voltage-gated calcium channels is essential for cellular signalling in a wide variety of cells and multiple physiological processes. Perturbations of voltage-gated calcium channel function can lead to pathophysiological consequences. Calcium binding proteins serve as calcium sensors and regulate the calcium channel properties via feedback mechanisms. This review highlights the current evidences of calcium binding protein-mediated channel regulation in human diseases.
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Schönrath K, Pan W, Klein-Szanto AJ, Braunewell KH. Involvement of VILIP-1 (visinin-like protein) and opposite roles of cyclic AMP and GMP signaling in in vitro cell migration of murine skin squamous cell carcinoma. Mol Carcinog 2010; 50:319-33. [PMID: 21480386 DOI: 10.1002/mc.20707] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 09/02/2010] [Accepted: 10/20/2010] [Indexed: 11/09/2022]
Abstract
VILIP-1 (visinin-like protein 1) is downregulated in various human squamous cell carcinoma (SCC). In a mouse skin SCC model VILIP-1 expression is reduced in aggressive tumor cells, accompanied by reduced cAMP levels. Overexpression of VILIP-1 in aggressive SCC cells led to enhanced cAMP production, in turn causing a reduction in invasive properties. Moreover, in primary neurons and neuronal tumor lines VILIP-1 enhanced cGMP signaling. Here, we set out to determine whether and how cAMP and cGMP signaling contribute to the VILIP-1 effect on enhanced SCC model cell migration, and thus most likely invasiveness in vivo. We found stronger increase in cGMP levels in aggressive, VILIP-1-negative SCC cells following stimulation of guanylyl cyclases NPR-A and -B with the natriuretic peptides ANP and CNP, respectively. Incubation with ANP or 8Br-cGMP to increase cGMP levels further enhanced the migration capacity of aggressive cells, whereas cell adhesion was unaffected. Increased cGMP was caused by elevated expression levels of NPR-A and -B. However, the expression level of VILIP-1 did not affect cGMP signaling and guanylyl cyclase expression in SCC. In contrast, VILIP-1 led to reduced migration of aggressive SCC cells depending on cAMP levels as shown by use of adenylyl cyclase (AC) inhibitor 2',3'-dideoxyadenosine. Involvement of cAMP-effectors PKA and EPAC play a role downstream of AC activation. VILIP-1-positive and -negative cells did not differ in mRNA expression of ACs, but an effect on enhanced protein expression and membrane localization of ACs was shown to underlie enhancement of cAMP production and, thus, reduction in cell migration by VILIP-1.
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Affiliation(s)
- Katharina Schönrath
- Signal Transduction Research Group, Institute for Neurophysiology, Charité, Universitätsmedizin Berlin, Berlin, Germany
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