Hepsin and maspin are inversely expressed in laser capture microdissectioned prostate cancer.
OBJECTIVE
Recent studies have shown that hepsin, a serine protease, is over expressed in prostate cancers, implicating hepsin activity in tumor invasion. Using microarray technology we have previously identified 22 genes that were up-regulated in high grade prostate cancers compared with benign prostatic hyperplasia. Of them hepsin was the most differentially over expressed. In the current report we compare hepsin to maspin (BD Transduction Laboratories, San Diego, California), a serine protease inhibitor (serpin), to measure the balance between levels of serine proteases and serpins, which are considered to be a critical determinant of net proteolytic activity.


METHODS
We combined the technique of laser capture microdissection with gene expression monitoring by micro-array analysis to investigate the gene expression profiles of prostate cells of different histological types. We also studied maspin immunohistochemically.


RESULTS
We observed that hepsin as well as 7 of 22 previously reported up-regulated genes demonstrated a pattern of increasing expression with increasing malignant phenotype. In contrast, the expression of maspin (a serpin) decreased with increasing malignancy of prostate cancers. Using immunohistochemistry we observed that maspin protein is expressed strongly in benign prostatic tissues and slightly in grade 3 prostate cancers, and is absent in grade 4/5 cancers.


CONCLUSIONS
We conclude that the increased ratio of hepsin-to-maspin may have an important role in prostate cancer progression and invasion.
Chen
Zuxiong
Z
Department of Urology, School of Medicine, Stanford University, Stanford, California 94305, USA.
Fan
Zhenbin
Z
McNeal
John E
JE
Nolley
Rosalie
R
Caldwell
Mitchell C
MC
Mahadevappa
Mamatha
M
Zhang
Zhaomei
Z
Warrington
Janet A
JA
Stamey
Thomas A
TA
D014408:Biomarkers, Tumor / Q000235:genetics*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D016147:Genes, Tumor Suppressor; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis; D011379:Prognosis; D011467:Prostate / Q000473:pathology; D011468:Prostatectomy; D011470:Prostatic Hyperplasia / Q000235:genetics / Q000473:pathology / Q000601:surgery; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D011506:Proteins / Q000235:genetics*; D012697:Serine Endopeptidases / Q000235:genetics*; D015843:Serpins / Q000235:genetics*; D015854:Up-Regulation / Q000502:physiology
D014408:Biomarkers, Tumor; D011506:Proteins; C085344:SERPIN-B5; D015843:Serpins; D012697:Serine Endopeptidases; C055645:hepsin