Unique expression pattern of the alpha6beta4 integrin and laminin-5 in human prostate carcinoma.
BACKGROUND
The alpha6beta4 integrin and its ligand, laminin-5, are essential gene products for the maintenance and remodeling of a stratified epithelium. Apparent loss of polarized alpha6beta4 integrin and laminin-5 protein expression in invasive prostate cancer as compared to normal prostate glands is known to occur. It is unknown whether these alterations occur in prostatic intraepithelial neoplasia (PIN) lesions and whether this combined defect occurs in other epithelial cancers.


METHODS
Human prostate tissues containing both normal, PIN, and cancerous regions and normal and cancer tissue from breast and colon were obtained at surgery and examined for beta4 integrin and laminin-5 using standard immunofluorescence staining methods.


RESULTS
Both normal prostate glands and PIN lesions contain beta4 integrin and laminin-5. Prostate carcinoma was unique in that both beta4 integrin and laminin-5 expression was uniformly absent. In contrast, the beta4 integrin and its ligand, laminin-5 were detected in all of the colon carcinoma cases and in 60% of the breast carcinomas.


CONCLUSIONS
The beta4 integrin and its ligand, laminin-5 are altered during the transition of PIN lesions to invasive prostate carcinoma. These data suggest the loss of these proteins during cancer progression. In both prostate and breast carcinoma, the normal expression pattern of the beta4 integrin and laminin-5 is interrupted, in contrast to the persistent beta4 integrin and laminin-5 expression detected in colon carcinoma.
Davis
T L
TL
Department of Radiation Oncology, University of Arizona, Tucson, AZ 85724-5043, USA.
Cress
A E
AE
Dalkin
B L
BL
Nagle
R B
RB
D000954:Antigens, Surface / Q000096:biosynthesis*; D001943:Breast Neoplasms / Q000378:metabolism; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D003110:Colonic Neoplasms / Q000378:metabolism; D018450:Disease Progression; D006801:Humans; D039161:Integrin alpha6beta4; D016023:Integrins / Q000096:biosynthesis*; D008297:Male; D008856:Microscopy, Fluorescence; D011467:Prostate / Q000378:metabolism; D019048:Prostatic Intraepithelial Neoplasia / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D013194:Staining and Labeling; D000097794:Kalinin
D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D039161:Integrin alpha6beta4; D016023:Integrins; D000097794:Kalinin