舌扁平上皮癌におけるアポトーシス関連因子の免疫組織学的ならびに分子生物学的検索と癌の病態に関する研究

抄録

The aim of this study was to investigate the relation of various apoptosis-associated factors with histological grades and clinical features of tongue squamous cell carcinoma (SCC). The subjects were 35 primary cases of tongue SCC: 25 cases had no recurrent tumor, one case had recurrence and 9 cases died. However, 2 cases of double cancer were included: one who had recurrence and one who died. Hematoxylin eosin (HE)-stained sections were examined to determine histological grades according to the WHO classification. TUNEL and immunohistochemical staining for Fas, Fas-ligand (Fas-L), bcl-x (bcl-xL), Bax, cpp32, Rb, p53 and ki-67 were performed, and their immunoreactivities were evaluated. p53-positive cases were screened for p53 mutation using PCRSSCP. The results were as follows:
1. Fas expression in histological grade II cases was lower (p = 0.093) than that in grade I cases. The expression was also decreased in 6 cases who died of tumor within 2 years and 2 cases who had double cancer as compared with other cases (p<0.05).
. The labeling index for p53 was significantly higher in 6 cases who died of tumor within 2 years and2 cases who had double cancer as compared to other cases (P<0.05).
3. Labeling indexes for TUNEL, Rb protein and ki-67 and expression of bcl-xL, bak, Fas-L and cpp 32 had no significant relation with grades of tumor differentiation and prognosis.
4. p 53 mutation was observed in exon 6, 7 and 8in 4 cases of 18 p53-positive cases. The number of cases was insufficient to clarify the relation of p53 mutation with histological grades and prognosis.
These results suggest that decline of Fas expression and increase of p53 expression indicate progression of histological grade and poor prognosis of tongue SCC.