Cholesterol depletion induces anoikis-like apoptosis via FAK down-regulation and caveolae internalization

Caveolae (lipid rafts), microdomains of the plasma membrane, are known to contain various signalling molecules and consequently are involved in the regulation of many biological functions. To investigate the role of the caveolae in cell survival and adhesion, we disrupted the caveolae by depletion of cholesterol, a major lipid component of the caveolae, with methyl-beta cyclodextrin (M beta CD) treatment of A431 cells. We found that cholesterol depletion induced an anoikis-like cell death involving actin reorganization, resulting in a decrease in cell spreading and an increase in cell detachment, which was reversed by cholesterol addition. Disruption of caveolae led to the down-regulation of FAK, Src activation, tyrosine phosphorylation of caveolin-1 and mobilization of caveolae markers, GM1 and caveolin-1, from the cell surface to the cytoplasm, which were also recovered by cholesterol addition. The expression of dominant-active FAK was able to delay caveolae internalization and apoptosis and attenuated Akt inactivation by M beta CD, whereas dominant-negative FAK expression resulted in enhanced apoptosis. Moreover, FAK down-regulation by si-RNA resulted in Akt inactivation and thus increased cell death by M beta CD treatment. Our results suggest that the cholesterol content and/or surface levels of the caveolae affect the activity of FAK, which in turn regulates caveolae internalization and cell survival. Copyright (C) 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.Lasserre R, 2008, NAT CHEM BIOL, V4, P538, DOI 10.1038/nchembio.103Fedida-Metula S, 2008, CARCINOGENESIS, V29, P1546, DOI 10.1093/carcin/bgn146Golubovskaya VM, 2008, MOL CARCINOGEN, V47, P373, DOI 10.1002/mc.20395Lim ST, 2008, MOL CELL, V29, P9, DOI 10.1016/j.molcel.2007.11.031Adam RM, 2007, CANCER RES, V67, P6238, DOI 10.1158/008-5472.CAN-07-0288Ramprasad OG, 2007, CELL MOTIL CYTOSKEL, V64, P199, DOI 10.1002/cm.20176Hess F, 2007, ONCOGENE, V26, P1372, DOI 10.1038/sj.onc.1209947Mitra SK, 2006, CURR OPIN CELL BIOL, V18, P516, DOI 10.1016/j.ceb.2006.08.011Gaus K, 2006, J CELL BIOL, V174, P725, DOI 10.1083/jcb.200603034Swaney JS, 2006, J BIOL CHEM, V281, P17173, DOI 10.1074/jbc.M513097200Huang Q, 2006, CANCER RES, V66, P5807, DOI 10.1158/0008-5472.CAN-06-0077Li YC, 2006, AM J PATHOL, V168, P1107, DOI 10.2353/ajpath.2006.050959Kirkham M, 2005, BBA-MOL CELL RES, V1746, P349, DOI 10.1016/j.bbamcr.2005.11.005Pankov R, 2005, ARCH BIOCHEM BIOPHYS, V442, P160, DOI 10.1016/j.abb.2005.08.003del Pozo MA, 2005, NAT CELL BIOL, V7, P901, DOI 10.1038/ncb1293Reddig PJ, 2005, CANCER METAST REV, V24, P425, DOI 10.1007/s10555-005-5134-3Grande-Garcia A, 2005, BIOCHEM SOC T, V33, P609McLean GW, 2005, NAT REV CANCER, V5, P505, DOI 10.1038/nrc1647Zhuang LY, 2005, J CLIN INVEST, V115, P959Le Roy C, 2005, NAT REV MOL CELL BIO, V6, P112, DOI 10.1038/nrm1571Mitra SK, 2005, NAT REV MOL CELL BIO, V6, P56, DOI 10.1038/nrm1549Hannigan G, 2005, NAT REV CANCER, V5, P51, DOI 10.1038/nrc1524LOZACOLL MA, 2005, ONCOGENE, V24, P1727Pietiainen V, 2004, MOL BIOL CELL, V15, P4911, DOI 10.1091/mbc.E04-01-0070Wozniak MA, 2004, BBA-MOL CELL RES, V1692, P103, DOI 10.1016/j.bbamcr.2004.04.007Shajahan AN, 2004, J BIOL CHEM, V279, P20392, DOI 10.1074/jbc.M308710200Pike LJ, 2004, BIOCHEM J, V378, P281, DOI 10.1042/BJ20031672Palazzo AF, 2004, SCIENCE, V303, P836Guan JL, 2004, SCIENCE, V303, P773del Pozo MA, 2004, SCIENCE, V303, P839Muppidi JR, 2004, NAT IMMUNOL, V5, P182, DOI 10.1038/ni1024Freeman MR, 2004, J CELL BIOCHEM, V91, P54, DOI 10.1002/jeb.10724Carver LA, 2003, NAT REV CANCER, V3, P571, DOI 10.1038/nrc1146Silvius JR, 2003, BBA-BIOMEMBRANES, V1610, P174, DOI 10.1016/S0005-2736(03)00016-6Kim YN, 2002, EXP CELL RES, V280, P134, DOI 10.1006/excr.2002.5623Grimmer S, 2002, J CELL SCI, V115, P2953Kim YN, 2002, ENDOCRINOLOGY, V143, P1726Zhuang LY, 2002, CANCER RES, V62, P2227Leitinger B, 2002, J CELL SCI, V115, P963Nichols BJ, 2001, TRENDS CELL BIOL, V11, P406Lee H, 2000, MOL ENDOCRINOL, V14, P1750Gilmore AP, 2000, J CELL BIOL, V149, P431Gopalakrishna P, 2000, J CELL BIOCHEM, V77, P517Kim YN, 2000, J BIOL CHEM, V275, P7481Subtil A, 1999, P NATL ACAD SCI USA, V96, P6775Rodal SK, 1999, MOL BIOL CELL, V10, P961Nomura R, 1999, MOL BIOL CELL, V10, P975Wei Y, 1999, J CELL BIOL, V144, P1285Wary KK, 1998, CELL, V94, P625Gervais FG, 1998, J BIOL CHEM, V273, P17102Anderson RGW, 1998, ANNU REV BIOCHEM, V67, P199Hungerford JE, 1996, J CELL BIOL, V135, P1383Frisch SM, 1996, J CELL BIOL, V134, P793OWENS LV, 1995, CANCER RES, V55, P2752GLENNEY JR, 1989, J BIOL CHEM, V264, P201631