PRIMA-1Met/APR-246 induces apoptosis and tumor growth delay in small cell lung cancer expressing mutant p53

TY - JOUR

T1 - PRIMA-1Met/APR-246 induces apoptosis and tumor growth delay in small cell lung cancer expressing mutant p53

AU - Zandi, Roza

AU - Selivanova, Galina

AU - Christensen, Camilla Laulund

AU - Gerds, Thomas Alexander

AU - Willumsen, Berthe Marie

AU - Poulsen, Hans Skovgaard

N1 - ©2011 AACR.

PY - 2011/5/1

Y1 - 2011/5/1

N2 - Purpose: Small cell lung cancer (SCLC) is a highly malignant disease with poor prognosis, necessitating the need to develop new and efficient treatment modalities. PRIMA-1Met (p53-dependent reactivation of massive apoptosis), also known as APR-246, is a small molecule, which restores tumor suppressor function to mutant p53 and induces cancer cell death in various cancer types. Since p53 is mutated in more than 90% of SCLC, we investigated the ability of PRIMA-1Met to induce apoptosis and inhibit tumor growth in SCLC with different p53 mutations. Experimental Design: The therapeutic effect of PRIMA-1Met/APR-246 was studied in SCLC cells in vitro using cell viability assay, fluorescence- activated cell-sorting analysis, p53 knockdown studies, and Western blot analyses. The antitumor potential of PRIMA-1Met/APR-246 was further evaluated in two different SCLC xenograft models. Results: PRIMA-1Met/APR-246 efficiently inhibited the growth of the SCLC cell lines expressing mutant p53 in vitro and induced apoptosis, associated with increased fraction of cells with fragmented DNA, caspase-3 activation, PARP cleavage, Bax and Noxa upregulation and Bcl-2 downregulation in the cells. The growth suppressive effect of PRIMA-1Met/APR-246 was markedly reduced in SCLC cell lines transfected with p53 siRNA, supporting the role of mutant p53 in PRIMA-1Met/APR-246-induced cell death. Moreover, in vivo studies showed significant antitumor effects of PRIMA-1Met after i.v. injection in SCLC mouse models with no apparent toxicity. Conclusion: This study is the first to show the potential use of p53-reactivating molecules such as PRIMA-1Met/APR-246 for the treatment of SCLC.

AB - Purpose: Small cell lung cancer (SCLC) is a highly malignant disease with poor prognosis, necessitating the need to develop new and efficient treatment modalities. PRIMA-1Met (p53-dependent reactivation of massive apoptosis), also known as APR-246, is a small molecule, which restores tumor suppressor function to mutant p53 and induces cancer cell death in various cancer types. Since p53 is mutated in more than 90% of SCLC, we investigated the ability of PRIMA-1Met to induce apoptosis and inhibit tumor growth in SCLC with different p53 mutations. Experimental Design: The therapeutic effect of PRIMA-1Met/APR-246 was studied in SCLC cells in vitro using cell viability assay, fluorescence- activated cell-sorting analysis, p53 knockdown studies, and Western blot analyses. The antitumor potential of PRIMA-1Met/APR-246 was further evaluated in two different SCLC xenograft models. Results: PRIMA-1Met/APR-246 efficiently inhibited the growth of the SCLC cell lines expressing mutant p53 in vitro and induced apoptosis, associated with increased fraction of cells with fragmented DNA, caspase-3 activation, PARP cleavage, Bax and Noxa upregulation and Bcl-2 downregulation in the cells. The growth suppressive effect of PRIMA-1Met/APR-246 was markedly reduced in SCLC cell lines transfected with p53 siRNA, supporting the role of mutant p53 in PRIMA-1Met/APR-246-induced cell death. Moreover, in vivo studies showed significant antitumor effects of PRIMA-1Met after i.v. injection in SCLC mouse models with no apparent toxicity. Conclusion: This study is the first to show the potential use of p53-reactivating molecules such as PRIMA-1Met/APR-246 for the treatment of SCLC.

U2 - 10.1158/1078-0432.ccr-10-3168

DO - 10.1158/1078-0432.ccr-10-3168

M3 - Journal article

C2 - 21415220

SN - 1078-0432

VL - 17

SP - 2830

EP - 2841

JO - Clinical Cancer Research

JF - Clinical Cancer Research

IS - 9

ER -