SMAC is expressed de novo in a subset of cervical cancer tumors.
BACKGROUND
Smac/Diablo is a recently identified protein that is released from mitochondria after apoptotic stimuli. It binds IAPs, allowing caspase activation and cell death. In view of its activity it might participate in carcinogenesis. In the present study, we analyzed Smac expression in a panel of cervical cancer patients.


METHODS
We performed semi quantitative RT-PCR on 41 cervical tumor and 6 normal tissue samples. The study included 8 stage I cases; 16 stage II; 17 stage III; and a control group of 6 samples of normal cervical squamous epithelial tissue.


RESULTS
Smac mRNA expression was below the detection limit in the normal cervical tissue samples. In contrast, 13 (31.7%) of the 41 cervical cancer biopsies showed detectable levels of this transcript. The samples expressing Smac were distributed equally among the stages (5 in stage I, 4 in stage II and 4 in stage III) with similar expression levels. We found no correlation between the presence of Smac mRNA and histology, menopause, WHO stage or disease status.


CONCLUSIONS
Smac is expressed de novo in a subset of cervical cancer patients, reflecting a possible heterogeneity in the pathways leading to cervical cancer. There was no correlation with any clinical variable.
Espinosa
Magali
M
Subdirección de Investigación Básica. Instituto Nacional de Cancerología, México, DF MEXICO. maggiec73@hotmail.com <maggiec73@hotmail.com>
Cantu
David
D
Lopez
Carlos M
CM
De la Garza
Jaime G
JG
Maldonado
Vilma A
VA
Melendez-Zajgla
Jorge
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins / Q000096:biosynthesis*; D045744:Cell Line, Tumor; D005260:Female; D006367:HeLa Cells / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008593:Menopause / Q000235:genetics; D008875:Middle Aged; D024101:Mitochondrial Proteins / Q000096:biosynthesis*; D009367:Neoplasm Staging; D018307:Neoplasms, Squamous Cell / Q000235:genetics*; D002583:Uterine Cervical Neoplasms / Q000235:genetics*
D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins; C412403:DIABLO protein, human; D047908:Intracellular Signaling Peptides and Proteins; D024101:Mitochondrial Proteins