Hsp-27 expression at diagnosis predicts poor clinical outcome in prostate cancer independent of ETS-gene rearrangement.

BACKGROUND: This study was performed to test the hypothesis that expression of small heat shock protein Hsp-27 is, at diagnosis, a reliable predictive biomarker of clinically aggressive prostate cancer. METHODS: A panel of tissue microarrays constructed from a well-characterised cohort of 553 men with conservatively managed prostate cancer was stained immunohistochemically to detect Hsp-27 protein. Hsp-27 expression was compared with a series of pathological and clinical parameters, including outcome. RESULTS: Hsp-27 staining was indicative of higher Gleason score (P<0.001). In tissue cores having a Gleason score >7, the presence of Hsp-27 retained its power to independently predict poor clinical outcome (P<0.002). Higher levels of Hsp-27 staining were almost entirely restricted to cancers lacking ERG rearrangements (chi2 trend=31.4, P<0.001), although this distribution did not have prognostic significance. INTERPRETATION: This study has confirmed that, in prostate cancers managed conservatively over a period of more than 15 years, expression of Hsp-27 is an accurate and independent predictive biomarker of aggressive disease with poor clinical outcome (P<0.001). These findings suggest that apoptotic and cell-migration pathways modulated by Hsp-27 may contain targets susceptible to the development of biologically appropriate chemotherapeutic agents that are likely to prove effective in treating aggressive prostate cancers.

TEAD1 and c-Cbl are novel prostate basal cell markers that correlate with poor clinical outcome in prostate cancer.

Prostate cancer is the most frequently diagnosed male cancer, and its clinical outcome is difficult to predict. The disease may involve the inappropriate expression of genes that normally control the proliferation of epithelial cells in the basal layer and their differentiation into luminal cells. Our aim was to identify novel basal cell markers and assess their prognostic and functional significance in prostate cancer. RNA from basal and luminal cells isolated from benign tissue by immunoguided laser-capture microdissection was subjected to expression profiling. We identified 112 and 267 genes defining basal and luminal populations, respectively. The transcription factor TEAD1 and the ubiquitin ligase c-Cbl were identified as novel basal cell markers. Knockdown of either marker using siRNA in prostate cell lines led to decreased cell growth in PC3 and disrupted acinar formation in a 3D culture system of RWPE1. Analyses of prostate cancer tissue microarray staining established that increased protein levels of either marker were associated with decreased patient survival independent of other clinicopathological metrics. These data are consistent with basal features impacting on the development and clinical course of prostate cancers.

Altered colonic glycoprotein expression in unaffected monozygotic twins of inflammatory bowel disease patients.

BACKGROUND AND AIMS: Previous chromatographic analysis of colonic mucins from monozygotic twins with inflammatory bowel disease (IBD) suggested a genetic mucin alteration in ulcerative colitis (UC). This study explores this further by assessing mucosal expression of the oncofetal carbohydrate antigen TF (galactose beta1, 3 N-acetylgalactosamine alpha-), among the same IBD twins. MATERIALS AND METHODS: Formalin fixed paraffin embedded rectal biopsies were studied from 22 monozygotic twin pairs with IBD. These included eight UC twin pairs and 14 Crohn's disease (CD) twin pairs, with six pairs concordant for disease and 16 unaffected twin siblings. Closely adjacent sections were assessed by peanut lectin histochemistry for TF expression and immunohistochemically for nuclear factor kappaB (NFkappaB) activation with investigators blinded to the diagnosis. RESULTS: Unaffected twins were almost all TF positive (15/16) compared with 5/29 histologically normal controls (p<0.0001). Unaffected UC (7/8) and CD twins (8/8) were similarly TF positive. TF positivity was confined mainly to the superficial epithelium and absent from the stem cell compartment of the lower crypts, suggesting that glycosylation changes are acquired rather than genetically determined. Activated NFkappaB was present in the surface epithelium of mucosal biopsies from 13/14 unaffected IBD twins but in only 6/22 histologically normal controls (p=0.0004). All 22 affected IBD twins were TF positive and 18 were positive for activated NFkappaB. CONCLUSIONS: Altered mucosal glycosylation in unaffected identical twins of IBD patients was confirmed in this study. This occurred in both UC and CD twins. The changes are probably acquired rather than congenital and may reflect "preinflammatory" NFkappaB activation.

Heat shock protein expression independently predicts clinical outcome in prostate cancer.

Heat shock proteins (hsps) occupy a central role in the regulation of intracellular homeostasis, and differential expression of individual hsps occurs in a broad range of neoplastic processes. This study was performed to test the hypothesis that the particular patterns by which individual hsps become specifically modulated in human prostate cancers are correlated with behavioral phenotype and hence may be of value in determining the most appropriate clinical management of individual patients. Monoclonal antibodies specific for each hsp protein were used to assess expression of hsp27, hsp60, and hsp70 in formalin-fixed, paraffin wax-embedded, archival tissue specimens of early prostatic adenocarcinomas (pT1-2N0M0) removed at radical prostatectomy (n = 25) and in advanced cancers (n = 95) identified at transurethral resection of prostate (TURP). These findings were compared with similar data from control prostates (n = 10) removed at primary cystectomy for urinary bladder neoplasia not involving the prostate and also at TURP for benign prostatic hyperplasia (n = 50). Western blotting of whole cell lysates derived from established human prostatic epithelial cell lines PNT2, LNCaP, DU145, and PC3 was compared with expression of hsps by the primary human tissues. This study found that early in situ neoplastic transformation of normal prostatic epithelium was consistently associated with loss of hsp27 expression and that the level of hsp27 expression by individual prostate cancers was correlated with their Gleason grade. In advanced cancers, hsp27 expression was invariably associated with poor clinical outcome (P = 0.0001). Data from cell lines supported the primary tissue findings, with elevated hsp27 expression only in aggressive malignant cell lines and androgen-insensitive cell lines. Expression of hsp60 was significantly increased in both early and advanced prostate cancer when compared with nonneoplastic prostatic epithelium (P < 0.0001), as well as in malignant prostate cancer cell lines. Expression of hsp70 was unaltered in early prostate cancers when compared with nonneoplastic prostatic epithelium but showed a diminished expression in morphologically advanced cancers (P = 0.0029). No consistent correlation was found between levels of hsp60 or hsp70 expression and phenotypic behavior of individual primary prostatic cancers. Thus, patterns of hsp expression have been confirmed to be specifically and consistently modulated in both early and advanced human prostate cancers. Whereas absence of hsp27 is a reliable objective marker of early prostatic neoplasia, reexpression of this protein by an individual invasive prostatic carcinoma invariably heralds poor clinical prognosis. Because this protein has been shown to alter the balance between proliferation and apoptosis, understanding the mechanism(s) by which individual hsps regulate intracellular homeostasis may assist in explaining some key processes that occur during evolution of human prostate cancers. We suggest that hsp27 expression provides novel diagnostic and prognostic information on individual patient survival which, if obtained at the time of primary diagnosis, would assist in determining tumor-specific management strategies. Development of techniques to therapeutically modulate hsp27 expression raises the possibility of novel targeted approaches to regulate this homeostatic mechanism, thus allowing better control over tumor cell proliferation and hence patient survival.

Ki-67, oestrogen receptor, and progesterone receptor proteins in the human rete ovarii and in endometriosis.

AIM: To examine proliferative activity using the Ki-67 protein, oestrogen receptor protein, and progesterone receptor protein expression in the rete ovarii, and to make comparisons with their expression in endometriosis. METHODS: Immunohistochemistry was used to study the rete ovarii in 24 cases and endometriosis in seven cases, using antibodies to Ki-67 protein (growth fraction (GF) quantified using a point score method) and oestrogen receptor and progesterone receptor (quantified using the H score method). RESULTS: There was no evidence of a significant difference in the Ki-67 protein, oestrogen receptor, and progesterone receptor in the rete ovarii in different phases of the menstrual cycle (proliferative phase: GF = 1.052, oestrogen receptor H score = 13.4, progesterone receptor H score = 15.32; secretory phase: GF = 0.736, oestrogen receptor H score = 7.5, progesterone receptor H score = 1.84). The expression of all three proteins was greater in the foci of endometriosis (GF = 6.99, oestrogen receptor H score = 152.02, progesterone receptor H score = 127.36) than in the rete ovarii (p < 0.0005-0.0008, Mann-Whitney U test). CONCLUSIONS: There is a low rate of cellular proliferation in the rete ovarii and this structure shows less responsiveness to hormone stimulation than foci of endometriosis. These differences may provide a useful tool to distinguish the rete ovarii from endometriosis in cases of diagnostic difficulty.

Differential expression of acidic and basic fibroblast growth factors in benign prostatic hyperplasia identified by immunohistochemistry.

OBJECTIVE: To detect the expression and to determine the relative cellular locations of the two peptide growth factors, acidic fibroblast growth factor (a-FGF) and basic (b)-FGF in tissues from human benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: A series of 50 sequential and unselected cases of human BPH tissues, obtained after transurethral prostatectomy, was examined. Adjacent sections of formalin-fixed and paraffin wax-embedded tissues were stained immunohistochemically for expression of a-FGF and b-FGF using well-characterized and commercially available antibodies. The stained tissue sections were assessed for the cellular distribution of immunohistochemical products and analysed according to the relative intensity of staining as well as the spatial relationships of positively stained cells. RESULTS: Acidic-FGF was weakly expressed with a pancytoplasmic distribution within luminal glandular epithelial cells in regions of prostatic intra-epithelial neoplasia (both PIN I and II) but not by non-dysplastic normal or hyperplastic tissues. No expression of a-FGF was detected in basal epithelial cells or in the stromal compartment of any tissue examined. In contrast, b-FGF was strongly expressed within the cytoplasm of all basal epithelial cells, but not by luminal epithelial cells, in morphologically normal regions of all cases examined. Basal expression of b-FGF was diminished, or absent, in regions of mild epithelial dysplasia, particularly those strongly expressing a-FGF. Extensive nuclear and cytoplasmic expression of b-FGF occurred predominantly in smooth muscle-type stromal cells but not in all types of stromal cells. CONCLUSIONS: This study confirmed both a differential and a reciprocal expression of a- and b-FGF in non-dysplastic prostatic hyperplasia and in mildly dysplastic regions of prostatic tissues. While only small amounts of a-FGF were expressed in BPH, exclusively in the luminal epithelial compartment, its consistent appearance in PIN I and II suggests that it might contribute to the early stages of PIN. Conversely, b-FGF may be an important mediator of stromal-epithelial interaction during the pathogenesis of BPH. These results provide new information about the relative expression of these growth factors, particularly in the architectural relationships between different cell-types within normal and non-malignant prostatic tissues.

Nucleolar organizer regions in melanocytic dysplasia and melanoma.

Using silver (Ag) staining to demonstrate nucleolar organizer region-associated proteins (AgNORs), pigmented naevi exhibiting features of melanocytic dysplasia have been examined and compared with benign intradermal and compound naevi and with malignant melanomas. A highly significant difference was found between the numbers of AgNORs demonstrated in benign naevus cells and atypical melanocytes and in malignant melanocytes, suggesting that this technique may have a role in differentiating between difficult melanocytic lesions.