Immunohistochemical expression of p63 in endometrial polyps: evidence that a basal cell immunophenotype is maintained.
OBJECTIVE
Although endometrial polyps likely originate from reserve cells in the basal layer, the underlying biology is not fully understood. One protein that plays an important role in regulating epithelial proliferation and differentiation is the 63-kd membrane protein (p63), which is also a marker of basal and reserve cells in the female genital tract. Our objective was to determine whether p63 is expressed differently in postmenopausal endometrial polyps than in the adjacent endometrium.


METHODS
In this study, 36 specimens of endometrial polyps and 36 samples of the adjacent endometrium were obtained from postmenopausal women through hysteroscopic surgery performed in a tertiary-care university hospital. Immunohistochemistry was used to evaluate the expression of p63 in all samples.


RESULTS
The majority of endometrial polyp samples (94.4%) presented nuclear immunostaining for p63, whereas only 5.6% of adjacent endometrium samples were positive for p63 (P < 0.0001). Distribution of p63 immunostaining in the endometrial polyp samples was homogeneous.


CONCLUSIONS
Our results provide evidence that a basal cell immunophenotype is maintained in the endometrial polyps seen in postmenopausal women, suggesting that p63 plays a role in the pathogenesis of such polyps.
Nogueira
Antonio Alberto
AA
Departamento de Ginecologia e Obstetrícia da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, São Paulo, Brazil. aanoguei@fmrp.usp.br
Sant'Ana de Almeida
Elza Carvalho
EC
Poli Neto
Omero Benedicto
OB
Zambelli Ramalho
Leandra Naira
LN
Rosa e Silva
Júlio César
JC
Candido dos Reis
Francisco José
FJ
D000368:Aged; D016009:Chi-Square Distribution; D004717:Endometrium / Q000276:immunology* / Q000601:surgery; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015907:Hysteroscopy; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000276:immunology; D008875:Middle Aged; D011127:Polyps / Q000276:immunology* / Q000601:surgery; D017698:Postmenopause; D014591:Uterine Diseases / Q000276:immunology* / Q000601:surgery
C081876:CKAP4 protein, human; D008565:Membrane Proteins