HPV+ cervical carcinomas and cell lines display altered expression of caspases.
OBJECTIVE
Loss of expression of apoptotic regulatory proteins in many neoplasias might result in defective or delayed apoptosis, thus facilitating tumor growth or survival. We analyzed here, the basal expression of precursors of apoptotic Caspases in normal cervical epithelium, HPV+ cervical tumor samples and HPV+ tumor-derived cell lines.


METHODS
Expression of initiator and effector Caspases was analyzed by immunochemistry in normal cervical epithelium and three types of cervical tumors (squamous cell carcinoma, adenocarcinoma and adenosquamous cell carcinoma) whereas expression of Caspases in HeLa, SiHa and CaSki cells was by immunofluorescence, Western blot and RT-PCR. Besides, the effect of the HPV-16 E6/E7 oncogenes on Caspases expression in cervical cells was evaluated by transfecting C33-A (HPV-) cells.


RESULTS
Expression of Caspases 3 and 9 was undetectable in adenocarcinoma and adenosquamous cell carcinoma, respectively. Whereas in squamous cell carcinoma, the expression of Caspases was similar those observed in normal samples. Expression of Caspases 3 and 6 was low in HeLa and CaSki cells, while Caspase 8 was low in SiHa and it was not detected in C33-A cells. All Caspases were detected in the cytoplasm and nucleus of the cells. We did not observe an effect of the E6/E7 oncogenes on the expression of Caspases in C33-A cell.


CONCLUSIONS
Our results showed a differential expression of several Caspases in carcinoma samples and cell lines, suggesting multiple alterations of the Caspase pathways in cervical cancer.
Aréchaga-Ocampo
Elena
E
Depto. Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados-IPN, Unidad Zacatenco, México, DF, 07360 México.
Pereira-Suárez
Ana Laura
AL
del Moral-Hernández
Oscar
O
Cedillo-Barrón
Leticia
L
Rodríguez-Sastre
Maria Alexandra
MA
Castillo-Alvarez
Aída
A
López-Bayghen
Esther
E
Villegas-Sepúlveda
Nicolás
N
D000230:Adenocarcinoma / Q000201:enzymology / Q000473:pathology / Q000821:virology; D015153:Blotting, Western; D018196:Carcinoma, Adenosquamous / Q000201:enzymology / Q000473:pathology / Q000821:virology; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000473:pathology / Q000821:virology; D020169:Caspases / Q000096:biosynthesis*; D045744:Cell Line, Tumor; D005260:Female; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D052162:Human papillomavirus 16; D052161:Human papillomavirus 18; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000096:biosynthesis; D030361:Papillomavirus Infections / Q000201:enzymology* / Q000473:pathology; D016612:Paraffin Embedding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D002583:Uterine Cervical Neoplasms / Q000201:enzymology* / Q000473:pathology / Q000821:virology*
D007527:Isoenzymes; D020169:Caspases