Localization of type IV collagen in the basement membranes of human prostate and lymph nodes by immunoperoxidase and immunoalkaline phosphatase

Abstract

The object of these studies was to examine the localization of type IV collagen (Coll-IV) in the basement membranes (BM) of epithelial and stromal elements (smooth muscle, nerves, vessels) in normal, hyperplastic, and neoplastic (primary and metastatic) prostate. We also examined the relationship of Coll-IV distribution to the degree of tumor differentiation (Gleason grading system). We compared immunoperoxidase (IP) and immunoalkaline phosphatase (AP) techniques in these studies and in selected samples we also evaluated immunofluorescence (IF) localization of Coll-IV and the effects of tissue fixation and pepsin digestion. We found that IF localization of Coll-IV was intense in unfixed sections. IP and AP reactions were absent in fixed, paraffin-embedded sections but pepsin treatment yielded intense and uniform reaction products in these same preparations. Both the IP and AP techniques showed similar localization of Coll-IV in the BM of normal, hyperplastic, and well-differentiated tumor. In most of the higher-grade tumors Coll-IV localization was reduced and a similar pattern of distribution was observed after IP and AP techniques. However, in some high-grade tumors the IP technique showed good localization but AP did not, and vice versa. Such discrepancies were noted in the BM of the tumor cells, as well as in the BM of the stromal elements and in lymph nodes with metastatic tumor. Thus, our study shows decreased Coll-IV localization in higher-grade tumors and suggests that the use of a single technique (IP or AP) may exaggerate this apparent loss of Coll-IV BM components. The exact cause of these discrepancies is unknown but they must reflect variable losses in the ability of the tumor cells to form BM, degradation or decreased synthesis of BM components by high-grade tumors, or a combination of the above.

Prostatic ductal system in rats: Changes in regional distribution of extracellular matrix proteins during castration-induced regression

“…In the normal rat ventral prostate, we have found that both laminin and collagen type IV were localized in the welldefined basement membrane of the epithelium, consistent with the findings in human prostatic epithelium as well as other epithelia [11][12][13]. Laminin was localized in the basement membrane along all regions of the prostate ductal system, similar to what has been found in the normal human prostate, BPH, and welldifferentiated carcinomas [11].…”

Characterization of Autocrine Growth Factors, Their Receptors and Extracellular Matrix Present in Three-Dimensional Cultures of DU 145 Human Prostate Carcinoma Cells Grown in Simulated Microgravity

“…15 The staining intensity for collagen IV in the basal lamina is stronger in well-differentiated prostatic tumors than in highly aggressive ones. 31 In our investigation, staining intensities for collagen IV and laminin were significantly more intense in HARV cultures relative to its controls. This accumulation of matrix proteins is consistent with the portrayal of the HARV culture as the least aggressive in our study.…”

Cathepsin K mRNA and Protein Expression in Prostate Cancer Progression

“…We observed cat K protein in cancerous glands of approximately 40% of the primary CaP tissues tested, exhibiting no correlation with Gleason score or cancer grade. Although prostate basement membrane consists primarily of type IV collagen (36, 37) and laminin, (38, 39) Burns‐Cox et al (40) observed an increase in type I collagen synthesis and degradation at the cancer foci in biopsy specimens from patients with primary CaP. Enzymes that cleave type I collagen, such as the cathepsins and MMPs, are reported to be upregulated in CaP (17,41–46) .…”