Florian R. Fritzsche

Histone deacetylases 1, 2 and 3 are highly expressed in prostate cancer and HDAC2 expression is associated with shorter PSA relapse time after radical prostatectomy

High activity of histone deacetylases (HDACs) causes epigenetic alterations associated with malignant cell behaviour. Consequently, HDAC inhibitors have entered late-phase clinical trials as new antineoplastic drugs. However, little is known about expression and function of specific HDAC isoforms in human tumours including prostate cancer. We investigated the expression of class I HDACs in 192 prostate carcinomas by immunohistochemistry and correlated our findings to clinicopathological parameters including follow-up data. Class I HDAC isoforms were strongly expressed in the majority of the cases (HDAC1: 69.8%, HDAC2: 74%, HDAC3: 94.8%). High rates of HDAC1 and HDAC2 expression were significantly associated with tumour dedifferentiation. Strong expression of all HDACs was accompanied by enhanced tumour cell proliferation. In addition, HDAC2 was an independent prognostic marker in our prostate cancer cohort. In conclusion, we showed that the known effects of HDACs on differentiation and proliferation of cancer cells observed in vitro can also be confirmed in vivo. The class I HDAC isoforms 1, 2 and 3 are differentially expressed in prostate cancer, which might be important for upcoming studies on HDAC inhibitors in this tumour entity. Also, the highly significant prognostic value of HDAC2 clearly deserves further study.

Class I histone deacetylases 1, 2 and 3 are highly expressed in renal cell cancer

BackgroundEnhanced activity of histone deacetylases (HDAC) is associated with more aggressive tumour behaviour and tumour progression in various solid tumours. The over-expression of these proteins and their known functions in malignant neoplasms has led to the development of HDAC inhibitors (HDI) as new anti-neoplastic drugs. However, little is known about HDAC expression in renal cell cancer.MethodsWe investigated the expression of HDAC 1, 2 and 3 in 106 renal cell carcinomas and corresponding normal renal tissue by immunohistochemistry on tissue micro arrays and correlated expression data with clinico-pathological parameters including patient survival.ResultsAlmost 60% of renal cell carcinomas expressed the HDAC isoforms 1 and 2. In contrast, HDAC 3 was only detected in 13% of all renal tumours, with particular low expression rates in the clear cell subtype. HDAC 3 was significantly higher expressed in pT1/2 tumours in comparison to pT3/4 tumours. Expression of class I HDAC isoforms correlated with each other and with the proliferative activity of the tumours. We found no prognostic value of the expression of any of the HDAC isoforms in this tumour entity.ConclusionClass I HDAC isoforms 1 and 2 are highly expressed in renal cell cancer, while HDAC 3 shows low, histology dependent expression rates. These unexpected differences in the expression patterns suggests alternative regulatory mechanisms of class I HDACs in renal cell cancer and should be taken into account when trials with isoform selective HDI are being planned. Whether HDAC expression in renal cancers is predictive of responsiveness for HDI will have to be tested in further studies.

Cytoplasmic overexpression of ALCAM is prognostic of disease progression in breast cancer

Background: Activated leucocyte cell adhesion molecule (ALCAM, CD166) is a cell surface member of the immunoglobulin superfamily. ALCAM expression has prognostic relevance in prostate and colon cancer. Objective: To evaluate ALCAM protein expression in breast cancer by immunohistochemistry and to correlate expression levels with clinicopathological data. Methods: 162 primary breast carcinomas with a mean clinical follow up time of 53 months were immunostained using a monoclonal ALCAM antibody. The staining was evaluated as an immunoreactive score (IRS) and grouped into low v high for both membranous and cytoplasmic staining. Results: Intraductal and invasive carcinomas showed a higher ALCAM expression (median IRS 4 and 6 respectively) than normal breast tissue (IRS 2). In univariate survival analyses a significant association of high cytoplasmic ALCAM expression with shortened patient disease-free survival (mean (SD) five year non-progression rate, 69.4 (4.6)% v 49.4 (11.1)%, p = 0.0142) was found. In multivariate analyses of disease-free survival times, high cytoplasmic ALCAM expression (relative risk (RR) = 2.086, p = 0.026) and nodal status (RR = 2.246, p = 0.035) were significantly associated with earlier disease progression, whereas tumour grading (RR = 1.6, p = 0.052) was of borderline significance. Conclusions: The data suggest that strong cytoplasmic ALCAM expression in primary breast cancer, as detected by immunohistochemistry, might be a new marker for a more aggressive breast cancer biology.

Prevalence of TMPRSS2-ERG and SLC45A3-ERG gene fusions in a large prostatectomy cohort

The majority of prostate cancers harbor recurrent gene fusions between the hormone-regulated TMPRSS2 and members of the ETS family of transcription factors, most commonly ERG. Prostate cancer with ERG rearrangements represent a distinct sub-class of tumor based on studies reporting associations with histomorphologic features, characteristic somatic copy number alterations, and gene expression signatures. This study describes the frequency of ERG rearrangement prostate cancer and three 5 prime (5′) gene fusion partners (ie, TMPRSS2, SLC45A3, and NDRG1) in a large prostatectomy cohort. ERG gene rearrangements and mechanism of rearrangement, as well as rearrangements of TMPRSS2, SLC45A3, and NDRG1, were assessed using fluorescence in situ hybridization (FISH) on prostate cancer samples from 614 patients treated using radical prostatectomy. ERG rearrangement occurred in 53% of the 540 assessable cases. TMPRSS2 and SLC45A3 were the only 5′ partner in 78% and 6% of these ERG rearranged cases, respectively. Interestingly, 11% of the ERG rearranged cases showed concurrent TMPRSS2 and SLC45A3 rearrangements. TMPRSS2 or SLC45A3 rearrangements could not be identified for 5% of the ERG rearranged cases. From these remaining cases we identified one case with NDRG1 rearrangement. We did not observe any associations with pathologic parameters or clinical outcome. This is the first study to describe the frequency of SLC45A3–ERG fusions in a large clinical cohort. Most studies have assumed that all ERG rearranged prostate cancers harbor TMPRSS2–ERG fusions. This is also the first study to report concurrent TMPRSS2 and SLC45A3 rearrangements in the same tumor focus, suggesting additional complexity that had not been previously appreciated. This study has important clinical implications for the development of diagnostic assays to detect ETS rearranged prostate cancer. Incorporation of these less common ERG rearranged prostate cancer fusion assays could further increase the sensitivity of the current PCR-based approaches.

GOLPH2 protein expression as a novel tissue biomarker for prostate cancer: implications for tissue-based diagnostics

GOLPH2 is coding the 73-kDa type II Golgi membrane antigen GOLPH2/GP73. Upregulation of GOLPH2 mRNA has been recently reported in expression array analyses of prostate cancer. As GOLPH2 protein expression in prostate tissues is currently unknown, this study aimed at a comprehensive analysis of GOLPH2 protein in benign and malignant prostate lesions. Immunohistochemically detected GOLPH2 protein expression was compared with the basal cell marker p63 and the prostate cancer marker α-methylacyl-CoA racemase (AMACR) in 614 radical prostatectomy specimens. GOLPH2 exhibited a perinuclear Golgi-type staining pattern and was preferentially seen in prostatic gland epithelia. Using a semiquantitative staining intensity score, GOLPH2 expression was significantly higher in prostate cancer glands compared with normal glands (P<0.001). GOLPH2 protein was upregulated in 567 of 614 tumours (92.3%) and AMACR in 583 of 614 tumours (95%) (correlation coefficient 0.113, P=0.005). Importantly, GOLPH2 immunohistochemistry exhibited a lower level of intratumoral heterogeneity (25 vs 45%). Further, GOLPH2 upregulation was detected in 26 of 31 (84%) AMACR-negative prostate cancer cases. These data clearly suggest GOLPH2 as an additional ancillary positive marker for tissue-based diagnosis of prostate cancer.

Golgi phosphoprotein 2 (GOLPH2) expression in liver tumors and its value as a serum marker in hepatocellular carcinomas.

Hepatocellular carcinomas (HCCs) and bile duct carcinomas (BDCs) have a poor prognosis. Therefore, surveillance strategies including sensitive and specific serum markers for early detection are needed. Recently, Golgi Phosphoprotein 2 (GOLPH2) has been proposed as a serum marker for HCC, but GOLPH2 expression data in liver tissues was not available. Using tissue microarrays and immunohistochemistry, we semiquantitatively analyzed GOLPH2 protein expression in patients with HCC (n = 170), benign liver tumors (n = 22), BDC (n = 114) and normal liver tissue (n = 105). A newly designed sandwich enzyme‐linked immunoassay (ELISA) was used to analyze GOLPH2 levels in the sera of patients with HCC (n = 62), hepatitis C virus (HCV) (n = 29), BDC (n = 10), and healthy control persons (n = 12). By immunohistochemistry 121/170 (71%) of HCC showed strong GOLPH2 expression, which was significantly associated with a higher tumor grade (P = 0.01). A total of 97/114 (85%) BDCs showed a strong GOLPH2 expression which proved to be an independent prognostic factor for overall survival (P < 0.05). Serum levels of GOLPH2 measured by ELISA were significantly elevated in patients with HCC with underlying HCV infection (median 18 mg/L, P < 0.05) and patients with BDC (median = 14.5 mg/L, P < 0.01) in comparison to healthy controls (median 4 mg/L). Conclusion: GOLPH2 protein is highly expressed in tissues of HCC and BDC. GOLPH2 protein levels are detectable and quantifiable in sera by ELISA. In patients with hepatitis C, serial ELISA measurements in the course of the disease appear to be a promising complementary serum marker in the surveillance of HCC. GOLPH2 should be further evaluated as a serum tumor marker in BDC on a larger scale. (HEPATOLOGY 2009.)

Tumoural CXCL16 expression is a novel prognostic marker of longer survival times in renal cell cancer patients

The aim of our study was to analyse the expression of CXCL16, ADAM10 and CXCR6 in renal cell carcinoma (RCC) tissue and to correlate the expression pattern with clinicopathologic data, including patient survival. Furthermore, we investigated CXCL16, ADAM10 and CXCR6 expressions by FACS, immunofluorescence and ELISA analysis in renal carcinoma cell lines. Our immunohistochemical analysis on tissue microarray of renal cancer samples of 104 patients revealed that ADAM10 correlated significantly with tumour stage, pathological nodal status, M status and lymphangiosis carcinomatosa. CXCL16, CXCR6 and ADAM10 were significantly increased in papillary carcinomas. Importantly, high levels of CXCL16 expression in renal cancer tissue correlated with better survival of patients, and CXCL16 correlated inversely to the tumour stage. In addition, inhibition of CXCL16 induced the migration of renal cancer cells assuming an anti-migratory function of transmembrane CXCL16. Taken together, our data demonstrate that downregulation of CXCL16 plays an important role in renal cancer development and progression, and that CXCL16 in RCC is an independent prognostic marker for better patient survival.

Prognostic Relevance of AGR2 Expression in Breast Cancer

Purpose: We aimed to evaluate the expression of the human anterior gradient-2 (AGR2) in breast cancer on RNA and protein level and to correlate it with clinicopathologic data, including patient survival. Experimental Design:AGR2 mRNA expression was assessed by reverse transcription-PCR in 25 breast cancer samples and normal tissues. A polyclonal rabbit AGR antiserum was used for immunohistochemistry on 155 clinicopathologically characterized cases. Statistical analyses were applied to test for prognostic and diagnostic associations. Results: Immunohistochemical detection of AGR2 was statistically significantly associated with positive estrogen receptor status and lower tumor grade. AGR2-positive tumors showed significantly longer overall survival times in univariate analyses. For the subgroup of nodal-negative tumors, an independent prognostic value of AGR2 was found. Conclusions: The expression of AGR2 in breast cancer is strongly associated with markers of tumor differentiation (estrogen receptor positivity, lower tumor grade). A prognostic effect of AGR2 for overall survival could be shown, which became independently significant for the group of nodal-negative tumors.

Periostin is up-regulated in high grade and high stage prostate cancer

BackgroundExpression of periostin is an indicator of epithelial-mesenchymal transition in cancer but a detailed analysis of periostin expression in prostate cancer has not been conducted so far.MethodsHere, we evaluated periostin expression in prostate cancer cells and peritumoural stroma immunohistochemically in two independent prostate cancer cohorts, including a training cohort (n = 93) and a test cohort (n = 325). Metastatic prostate cancers (n = 20), hormone refractory prostate cancers (n = 19) and benign prostatic tissues (n = 38) were also analyzed.ResultsIn total, strong epithelial periostin expression was detectable in 142 of 418 (34.0%) of prostate carcinomas and in 11 of 38 benign prostate glands (28.9%). Increased periostin expression in carcinoma cells was significantly associated with high Gleason score (p < 0.01) and advanced tumour stage (p < 0.05) in the test cohort. Whereas periostin expression was weak or absent in the stroma around normal prostate glands, strong periostin expression in tumour stroma was found in most primary and metastatic prostate cancers. High stromal periostin expression was associated with higher Gleason scores (p < 0.001). There was a relationship between stromal periostin expression and shortened PSA relapse free survival times in the training cohort (p < 0.05).ConclusionsOur data indicate that periostin up-regulation is related to increased tumour aggressiveness in prostate cancer and might be a promising target for therapeutical interventions in primary and metastatic prostate cancer.

Expression analysis of mammaglobin A ( SCGB2A2 ) and lipophilin B ( SCGB1D2 ) in more than 300 human tumors and matching normal tissues reveals their co-expression in gynecologic malignancies

BackgroundMammaglobin A (SCGB2A2) and lipophilin B (SCGB1D2), two members of the secretoglobin superfamily, are known to be co-expressed in breast cancer, where their proteins form a covalent complex. Based on the relatively high tissue-specific expression pattern, it has been proposed that the mammaglobin A protein and/or its complex with lipophilin B could be used in breast cancer diagnosis and treatment. In view of these clinical implications, the aim of the present study was to analyze the expression of both genes in a large panel of human solid tumors (n = 309), corresponding normal tissues (n = 309) and cell lines (n = 11), in order to evaluate their tissue specific expression and co-expression pattern.MethodsFor gene and protein expression analyses, northern blot, dot blot hybridization of matched tumor/normal arrays (cancer profiling arrays), quantitative RT-PCR, non-radioisotopic RNA in situ hybridization and immunohistochemistry were used.ResultsCancer profiling array data demonstrated that mammaglobin A and lipophilin B expression is not restricted to normal and malignant breast tissue. Both genes were abundantly expressed in tumors of the female genital tract, i.e. endometrial, ovarian and cervical cancer. In these four tissues the expression pattern of mammaglobin A and lipophilin B was highly concordant, with both genes being down-, up- or not regulated in the same tissue samples. In breast tissue, mammaglobin A expression was down-regulated in 49% and up-regulated in 12% of breast tumor specimens compared with matching normal tissues, while lipophilin B was down-regulated in 59% and up-regulated in 3% of cases. In endometrial tissue, expression of mammaglobin A and lipophilin B was clearly up-regulated in tumors (47% and 49% respectively). Both genes exhibited down-regulation in 22% of endometrial tumors. The only exceptions to this concordance of mammaglobin A/lipophilin B expression were normal and malignant tissues of prostate and kidney, where only lipophilin B was abundantly expressed and mammaglobin A was entirely absent. RNA in situ hybridization and immunohistochemistry confirmed expression of mammaglobin A on a cellular level in endometrial and cervical cancer and their corresponding normal tissues.ConclusionAltogether, these data suggest that expression of mammaglobin A and lipophilin B might be controlled in different tissues by the same regulatory transcriptional mechanisms. Diagnostic assays based on mammaglobin A expression and/or the mammaglobin A/lipophilin B complex appear to be less specific for breast cancer, but with a broader spectrum of potential applications, which includes gynecologic malignancies.