Intracellular targets of RGDS peptide in melanoma cells

Molecular Cancer

Research

Claudia Giampietri¹  Paola Fortugno²  Gianluca Ragone³  Maria Simona Aguzzi⁴  Maurizio C. Capogrossi⁴  Antonio Facchiano⁴ 

[1] Dipartimento di Istologia e Embriologia Medica, Università di Roma "Sapienza", Roma, Italy;Laboratorio Biologia Molecolare e Cellulare, Istituto Dermopatico dell'Immacolata, IDI-IRCCS, Roma, Italy;Laboratorio Oncogenesi Molecolare, Istituto Dermopatico dell'Immacolata, IDI-IRCCS, Roma, Italy;Laboratorio Patologia Vascolare, Istituto Dermopatico dell'Immacolata, IDI-IRCCS, Roma, Italy;

关键词: Melanoma Cell;    Survivin Expression;    Intracellular Target;    Cytoplasmic Extract;    Specific Competitor;   

DOI  :  10.1186/1476-4598-9-84

 received in 2010-01-15, accepted in 2010-04-22,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundRGD-motif acts as a specific integrins-ligand and regulates a variety of cell-functions via extracellular action affecting cell-adhesion properties. However, increasing evidence identifies additional RGDS-functions at intracellular level. Previous reports show RGDS-internalization in endothelial cells, cardiomyocytes and lymphocytes, indicating intracellular targets such as caspase-8 and caspase-9, and suggest RGDS specific activity at cytoplasmic level. Given the role RGDS-peptides play in controlling proliferation and apoptosis in several cell types, investigating intracellular targets of RGDS in melanoma cells may un-reveal novel molecular targets and key pathways, potentially useful for a more effective approach to melanoma treatment.ResultsIn the present study we show for the first time that RGDS-peptide is internalized in melanoma cells in a time-dependent way and exerts strong anti-proliferative and pro-apoptotic effects independently from its extracellular anti-adhesive action. RGES control-peptide did not show biological effects, as expected; nevertheless it is internalized, although with slower kinetics. Survivin, a known cell-cycle and survival-regulator is highly expressed in melanoma cells. Co-immunoprecipitation assays in cell lysates and overlay assays with the purified proteins showed that RGDS interacts with survivin, as well as with procaspase-3, -8 and -9. RGDS-peptide binding to survivin was found to be specific, at high affinity (Kd 27.5 μM) and located at the survivin C-terminus. RGDS-survivin interaction appeared to play a key role, since RGDS lost its anti-mitogenic effect in survivin-deprived cells with a specific siRNA.ConclusionsRGDS inhibits melanoma growth with an adhesion-independent mechanism; it is internalized in melanoma cells and specifically interacts with survivin. The present data may indicate a novel role of RGDS-containing peptides physiologically released from the extracellular matrix and may suggest a possible novel anti-proliferation strategy in melanoma.

【 授权许可】

Unknown   
© Aguzzi et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.