Expression of IAP family proteins in esophageal cancer.
Members of the inhibitor of apoptosis protein (IAP) family, including survivin, have been reported to be expressed in many tumors. However, their expression in esophageal cancer has not been clarified completely. We investigated the expression of mRNA for IAP family proteins in samples from esophageal cancers and their adjacent normal mucosa tissues by real-time quantitative RT-PCR. The survivin expression in esophageal cancer was significantly higher than that in normal mucosa (P < 0.05). Other IAP family proteins including cIAP1, cIAP2, NAIP and XIAP tended to show stronger expression in cancer tissue than normal mucosa, although the differences were not significant. As to the histological type of tumor, poorly differentiated squamous cell carcinomas exhibited significantly higher level of expression than well-differentiated carcinomas (P < 0.05). The proportion of apoptotic cells of cancer tissue inversely correlated with the intensity of survivin expression (P < 0.05). Immunohistochemical staining demonstrated cytoplasmic as well as nuclear expression of survivin in esophageal cancer, and further, in situ hybridization analysis demonstrated cytoplasmic expression of mRNA for survivin. The results suggest that the expression of IAP family proteins, especially survivin, may be associated with the biological character of esophageal cancer, such as apoptosis.
Nemoto
Tetsuo
T
Department of Pathology and Immunology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
Kitagawa
Masanobu
M
Hasegawa
Maki
M
Ikeda
Satoshi
S
Akashi
Takumi
T
Takizawa
Touichiro
T
Hirokawa
Katsuiku
K
Koike
Morio
M
D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000235:genetics*; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D051034:Inhibitor of Apoptosis Proteins; D008297:Male; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins / Q000235:genetics*; D051616:Neuronal Apoptosis-Inhibitory Protein; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D044767:Ubiquitin-Protein Ligases; D051636:X-Linked Inhibitor of Apoptosis Protein
C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; C496800:NAIP protein, human; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D051616:Neuronal Apoptosis-Inhibitory Protein; D011506:Proteins; D012333:RNA, Messenger; D000077022:Survivin; D051636:X-Linked Inhibitor of Apoptosis Protein; C496866:XIAP protein, human; C494833:BIRC2 protein, human; D044767:Ubiquitin-Protein Ligases