Two N-terminal isoforms characterize the p63 protein: the transactivating isoform TAp63 and the aminoterminal truncated isoform dNp63. Two further N-terminal isoforms lacking exon 4 (d4TAp63 and dNp73L) have been reported. Purpose of the study was to investigate the molecular expression of N-terminal p63 isoforms in benign and malignant breast tissues. Eighteen randomly selected cases of invasive breast carcinoma (IBC) of luminal type, two cases of in situ duct carcinoma (DCIS/DIN), and 20 specimens of normal and benign breast tissues were studied. All cases were immunostained for p63. Reverse polymerase chain reaction and nested PCR were performed to evaluate p63 N-terminal expression patterns. These isoforms whenever present were validated by sequencing. All cases of normal breast, benign lesions, and the two cases of DCIS/DIN expressed dNp63 and TAp63 isoforms only. The two variants lacking exon 4 (dNp73L and d4TAp63) were not found. All invasive carcinomas expressed the dNp63 and TAp63 isoforms as well as the two short isoforms lacking exon 4 which were found in 11 (d4TAp63) and four (dNp73L) cases. The present cases of luminal-type IBC showed p63 isoforms together with short variants lacking exon 4. These isoforms were not observed in non-neoplastic breast tissue. Presence of p63 in invasive breast carcinomas of luminal type, as seen at molecular level, suggests caution to include p63 as a marker of basal-like carcinomas.
de Biase D., Morandi L., Degli Esposti R., Ligorio C., Pession A., Foschini M.P., et al. (2010). p63 short isoforms are found in invasive carcinomas only and not in benign breast conditions. VIRCHOWS ARCHIV, 456, 395-401 [10.1007/s00428-010-0900-1].
p63 short isoforms are found in invasive carcinomas only and not in benign breast conditions
DE BIASE, DARIO;MORANDI, LUCA;LIGORIO, CLAUDIA;PESSION, ANNALISA;FOSCHINI, MARIA PIA;EUSEBI, VINCENZO
2010
Abstract
Two N-terminal isoforms characterize the p63 protein: the transactivating isoform TAp63 and the aminoterminal truncated isoform dNp63. Two further N-terminal isoforms lacking exon 4 (d4TAp63 and dNp73L) have been reported. Purpose of the study was to investigate the molecular expression of N-terminal p63 isoforms in benign and malignant breast tissues. Eighteen randomly selected cases of invasive breast carcinoma (IBC) of luminal type, two cases of in situ duct carcinoma (DCIS/DIN), and 20 specimens of normal and benign breast tissues were studied. All cases were immunostained for p63. Reverse polymerase chain reaction and nested PCR were performed to evaluate p63 N-terminal expression patterns. These isoforms whenever present were validated by sequencing. All cases of normal breast, benign lesions, and the two cases of DCIS/DIN expressed dNp63 and TAp63 isoforms only. The two variants lacking exon 4 (dNp73L and d4TAp63) were not found. All invasive carcinomas expressed the dNp63 and TAp63 isoforms as well as the two short isoforms lacking exon 4 which were found in 11 (d4TAp63) and four (dNp73L) cases. The present cases of luminal-type IBC showed p63 isoforms together with short variants lacking exon 4. These isoforms were not observed in non-neoplastic breast tissue. Presence of p63 in invasive breast carcinomas of luminal type, as seen at molecular level, suggests caution to include p63 as a marker of basal-like carcinomas.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
