请教各位老师，如何理解p63在胞浆中表达？
Characteristic Morphology of Invasive Micropapillary Carcinoma of the Breast: An Immunohistochemical Analysis   Jpn J Clin Oncol 2010;40(8)781–787
Objective: Invasive micropapillary carcinoma of the breast is a distinct variant of breast
cancer. In the present study, we analyzed potential immunophenotypic changes in invasive
micropapillary carcinoma.
Methods: Specimens from 15 patients with invasive micropapillary carcinoma were analyzed
using clinicopathological and immunohistochemical methods. We also examined the relationship
between clinicopathological factors using the Ki-67 labeling index.
Results: Immunohistochemical staining for cytoplasmic p63 expression was seen in four
(27%) tumors, and p63 nuclear expression was also observed in four (27%) tumors.
Involucrin and 34betaE12 were expressed in the invasive micropapillary carcinoma component
of nine (60%) and four (27%) tumors, respectively. Cytokeratin 5/6 was expressed in
three (20%) tumors and cytokeratin 14 staining was negative in all tumors. In one tumor
(case 3), vimentin, epithelial membrane antigen and cytokeratin 8/18 were co-expressed.
Four tumors (27%) were negative for the estrogen receptor/progesterone receptor/HER2.
However, 11 out of 15 (73%) tumors were positive for the estrogen receptor. The Ki-67 labeling
index was significantly higher in cases with p63 tumor expression than in those without
(P , 0.0001), and also higher in cases with lymph node metastasis than in cases without
(P ¼ 0.0029).
Conclusions: Nuclear expression of p63, involucrin and 34betaE12 were detected indicating
squamous differentiation. Cytoplasmic p63 expression was also identified. The fact that the
Ki-67 labeling index was significantly higher in such cases may have been associated with
the aggressive behavior of these tumors. Our findings suggest that the characteristic morphology
of invasive micropapillary carcinomas may be due to immunophenotypical and oncogenic
changes.
In the present study, cytoplasmic expression of p63 was
identified in some IMPC tumors. Cytoplasmic p63
expression in IMPCs has not been reported previously.
However, cytoplasmic localization of p63 has been
reported in lung tumors and is associated with poor patient
survival (16). It is also correlated with high tumor grade
in meningiomas (17) and increased mortality in prostate
cancer patients (18). The cytoplasmic staining of p63, a
transcription factor involved in transactivation, apoptosis
and proliferation that usually stains in the nucleus, may suggest an altered and potentially oncogenic function (18).
The clinical significance of cytoplasmic p63 expression in
breast cancer is unknown, but a similar morphological and immunohistochemical profile of cytoplasmic p63 expression
in secretory carcinomas and pregnancy-associated carcinomas
has been reported (12,13).