Staining pattern of specific and cross-reacting Melan-A antibodies: A comparative study on 15,840 samples from 133 human tumor types.

The Melan-A (melanocyte antigen) protein, also termed 'melanoma antigen recognized by T cells 1' (MART-1) is a protein with unknown function whose expression is specific for the melanocyte lineage. Antibodies against Melan-A are thus used for identifying melanocytic tumors, but some Melan-A antibodies show an additional - diagnostically useful - cross-reactivity against an unspecified protein involved in corticosteroid hormone synthesis. To comprehensively compare the staining patterns of a specific and a cross-reactive Melan-A antibody in normal and neoplastic tissues, tissue microarrays containing 15,840 samples from 133 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. For the Melan-A-specific antibody 'Melan-A specific' (MSVA-900M), Melan-A positivity was seen in 96.0% of 25 benign nevi, 93.0% of 40 primary and 86.7% of 75 metastatic melanomas, 82.4% of 85 renal angiomyolipomas as well as 96.4% of 84 neurofibromas, 2.2% of 46 granular cell tumors, 1.0% of 104 schwannomas, and 1.1% of 87 leiomyosarcomas. The cross-reactive antibody 'Melan-A+' (MSVA-901M+) stained 98.1% of the tumors stained by 'Melan-A specific'. In addition, high positivity rates were seen in sex-cord-stroma tumors of the ovary (35.3%-100%) and the testis (86.7%) as well as for adrenocortical neoplasms (76.3%-83.0%). Only nine further tumor groups showed Melan-A+ staining, including five different categories of urothelial carcinomas. Our data provide a comprehensive overview on the staining patterns of specific and cross-reactive Melan-A antibodies. The data demonstrate that both antibodies are highly useful for their specific purpose. It is important for pathologists to distinguish these two Melan-A antibody subtypes for their daily work.

Epithelial Cell Adhesion Molecule (EpCAM) Expression in Human Tumors: A Comparison with Pan-Cytokeratin and TROP2 in 14,832 Tumors.

EpCAM is expressed in many epithelial tumors and is used for the distinction of malignant mesotheliomas from adenocarcinomas and as a surrogate pan-epithelial marker. A tissue microarray containing 14,832 samples from 120 different tumor categories was analyzed by immunohistochemistry. EpCAM staining was compared with TROP2 and CKpan. EpCAM staining was detectable in 99 tumor categories. Among 78 epithelial tumor types, the EpCAM positivity rate was ≥90% in 60 categories-including adenocarcinomas, neuroendocrine neoplasms, and germ cell tumors. EpCAM staining was the lowest in hepatocellular carcinomas, adrenocortical tumors, renal cell neoplasms, and in poorly differentiated carcinomas. A comparison of EpCAM and CKpan staining identified a high concordance but EpCAM was higher in testicular seminomas and neuroendocrine neoplasms and CKpan in hepatocellular carcinomas, mesotheliomas, and poorly differentiated non-neuroendocrine tumors. A comparison of EpCAM and TROP2 revealed a higher rate of TROP2 positivity in squamous cell carcinomas and lower rates in many gastrointestinal adenocarcinomas, testicular germ cell tumors, neuroendocrine neoplasms, and renal cell tumors. These data confirm EpCAM as a surrogate epithelial marker for adenocarcinomas and its diagnostic utility for the distinction of malignant mesotheliomas. In comparison to CKpan and TROP2 antibodies, EpCAM staining is particularly common in seminomas and in neuroendocrine neoplasms.

TRPS1 is a Highly Sensitive Marker for Breast Cancer: A Tissue Microarray Study Evaluating More Than 19,000 Tumors From 152 Different Tumor Entities.

Trichorhinophalangeal syndrome 1 (TRPS1) is a nuclear protein highly expressed in breast epithelial cells. TRPS1 immunohistochemistry (IHC) has been suggested as a breast cancer marker. To determine the diagnostic and prognostic utility of TRPS1 IHC, tissue microarrays containing 19,201 samples from 152 different tumor types and subtypes were analyzed. GATA3 IHC was performed in a previous study. TRPS1 staining was seen in 86 of 152 tumor categories with 36 containing at least one strongly positive case. TRPS1 staining predominated in various types of breast carcinomas (51%-100%), soft tissue tumors (up to 100%), salivary gland tumors (up to 46%), squamous cell carcinomas (up to 35%), and gynecological cancers (up to 40%). TRPS1 positivity occurred in 1.8% of 1083 urothelial neoplasms. In invasive breast carcinoma of no special type, low TRPS1 expression was linked to high grade ( P = 0.0547), high pT ( P < 0.0001), nodal metastasis ( P = 0.0571), loss of estrogen receptor and progesterone receptor expression ( P < 0.0001 each), and triple-negative status ( P < 0.0001) but was unrelated to patient survival ( P = 0.8016). In squamous cell carcinomas from 11 different sites, low TRPS1 expression was unrelated to tumor phenotype. Positivity for both TRPS1 and GATA3 occurred in 47.4% to 100% of breast cancers, up to 30% of salivary gland tumors, and 29 (0.3%) of 9835 tumors from 134 other cancer entities. TRPS1 IHC has high utility for the identification of cancers of breast (or salivary gland) origin, especially in combination with GATA3. The virtual absence of TRPS1 positivity in urothelial neoplasms is useful for the distinction of GATA3-positive urothelial carcinoma from breast cancer.

Steroidogenic Acute Regulatory Protein Is a Useful Marker for Sex-Cord-Stroma Tumors and Normal and Neoplastic Adrenocortical Tissue.

CONTEXT.­: Steroidogenic acute regulatory (StAR) protein is a mitochondrial transport protein with a critical regulatory role for steroid hormone production. The tissue distribution of StAR expression is limited to few human normal tissues. OBJECTIVE.­: To assess the diagnostic and prognostic value of StAR immunohistochemistry analysis. DESIGN.­: A tissue microarray containing 19 202 samples from 152 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. RESULT.­: StAR immunostaining occurred in 198 (1.2%) of the 17 135 analyzable tumors. StAR expression was observed in 27 of 152 tumor categories, 9 of which included at least 1 strongly positive case. The highest rate of StAR positivity occurred in Leydig cell tumors of the testis and the ovary (100%), steroid cell tumors of the ovary (100%), adrenocortical carcinomas (93%) and adenomas (87%), Sertoli-Leydig cell tumors (67%) and granulosa cell tumors of the ovary (56%), as well as seminomas (7%). Nineteen other tumor entities showed-a usually weak-StAR positivity in less than 6% of cases. A comparison with preexisting Melan-A (a melanocyte antigen) data revealed that StAR was more often positive in adrenocortical neoplasms and in Leydig cell tumors while StAR (but not Melan-A) was negative in Sertoli cell tumors. CONCLUSIONS.­: Our data provide a comprehensive overview on the patterns of StAR immunostaining in human tumors and suggest a diagnostic utility of StAR immunohistochemistry for supporting a diagnosis of Leydig cell tumors or of normal or neoplastic adrenocortical tissue.

Prostein expression in human tumors: a tissue microarray study on 19,202 tumors from 152 different Tumor entities.

BACKGROUND: Prostein (P501S), also termed solute carrier family 45 member 3 (SLC45A3) is an androgen regulated protein which is preferentially expressed in prostate epithelial cells. Because of its frequent expression in prostate cancer, prostein was suggested a diagnostic prostate cancer marker. METHODS: In order to comprehensively assess the diagnostic utility of prostein immunohistochemistry, a tissue microarray containing 19,202 samples from 152 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. RESULTS: Prostein immunostaining was typically cytoplasmic, granular and perinuclear. Prostein positivity was seen in 96.7% of 419 prostate cancers including 78.3% with strong staining. In 16,709 extra-prostatic tumors, prostein positivity was observed in 7.2% of all cases but only 0.3% had a strong staining. Overall, 50 different extra-prostatic tumor categories were prostein positive, 12 of which included at least one strongly positive case. Extra-prostatic tumors with highest rates of prostein positivity included different subtypes of salivary gland tumors (7.6-44.4%), neuroendocrine neoplasms (15.8-44.4%), adenocarcinomas of the gastrointestinal tract (7.3-14.8%), biliopancreatic adenocarcinomas (3.6-38.7%), hepatocellular carcinomas (8.1%), and adenocarcinomas of other organs (up to 21%). CONCLUSIONS: Our data provide a comprehensive overview on prostein expression in human cancers. Prostein is a highly sensitive prostate cancer marker occurring in > 96% of prostate cancers. Because prostein can also be expressed in various other tumor entities, classifying of a tumor mass as a prostate cancer should not be based on prostein positivity alone.

GAD2 Is a Highly Specific Marker for Neuroendocrine Neoplasms of the Pancreas.

Glutamate decarboxylase 2 (GAD2) is the most important inhibitory neurotransmitter and plays a role in insulin-producing ß cells of pancreatic islets. The limitation of GAD2 expression to a few normal cell types makes GAD2 a potential immunohistochemical diagnostic marker. To evaluate the diagnostic utility of GAD2 immunohistochemistry, a tissue microarray containing 19,202 samples from 152 different tumor entities and 608 samples of 76 different normal tissue types was analyzed. In normal tissues, GAD2 staining was restricted to brain and pancreatic islet cells. GAD2 staining was seen in 20 (13.2%) of 152 tumor categories, including 5 (3.3%) tumor categories containing at least 1 strongly positive case. GAD2 immunostaining was most commonly seen in neuroendocrine carcinomas (58.3%) and neuroendocrine tumors (63.2%) of the pancreas, followed by granular cell tumors (37.0%) and neuroendocrine tumors of the lung (11.1%). GAD2 was only occasionally (<10% of cases) seen in 16 other tumor entities including paraganglioma, medullary thyroid carcinoma, and small cell neuroendocrine carcinoma of the urinary bladder. Data on GAD2 and progesterone receptor (PR) expression (from a previous study) were available for 95 pancreatic and 380 extrapancreatic neuroendocrine neoplasms. For determining a pancreatic origin of a neuroendocrine neoplasm, the sensitivity of GAD2 was 64.2% and specificity 96.3%, while the sensitivity of PR was 56.8% and specificity 92.6%. The combination of PR and GAD2 increased both sensitivity and specificity. GAD2 immunohistochemistry is a highly useful diagnostic tool for the identification of pancreatic origin in case of neuroendocrine neoplasms with unknown site of origin.

Diagnostic Role and Prognostic Impact of PSAP Immunohistochemistry: A Tissue Microarray Study on 31,358 Cancer Tissues.

Prostate-specific acid phosphatase (PSAP) is a marker for prostate cancer. To assess the specificity and prognostic impact of PSAP, 14,137 samples from 127 different tumor (sub)types, 17,747 prostate cancers, and 76 different normal tissue types were analyzed via immunohistochemistry in a tissue microarray format. In normal tissues, PSAP staining was limited to the prostate epithelial cells. In prostate cancers, PSAP was seen in 100% of Gleason 3 + 3, 95.5% of Gleason 4 + 4, 93.8% of recurrent cancer under androgen deprivation therapy, 91.0% of Gleason 5 + 5, and 31.2% of small cell neuroendocrine cancer. In non-prostatic tumors, PSAP immunostaining was only found in 3.2% of pancreatic neuroendocrine tumors and in 0.8% of diffuse-type gastric adenocarcinomas. In prostate cancer, reduced PSAP staining was strongly linked to an advanced pT stage, a high classical and quantitative Gleason score, lymph node metastasis, high pre-operative PSA levels, early PSA recurrence (p < 0.0001 each), high androgen receptor expression, and TMPRSS2:ERG fusions. A low level of PSAP expression was linked to PSA recurrence independent of pre- and postoperative prognostic markers in ERG-negative cancers. Positive PSAP immunostaining is highly specific for prostate cancer. Reduced PSAP expression is associated with aggressive prostate cancers. These findings make PSAP a candidate marker for prognostic multiparameter panels in ERG-negative prostate cancers.

Cytokeratin 13 (CK13) expression in cancer: a tissue microarray study on 10,439 tumors.

Cytokeratin 13 (CK13) is a type I acidic low molecular weight cytokeratin, which is mainly expressed in urothelium and in the squamous epithelium of various sites of origin. Loss of CK13 has been implicated in the development and progression of squamous epithelial neoplasms. To comprehensively determine CK13 expression in normal and neoplastic tissues, a tissue microarray containing 10,439 samples from 131 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. CK13 immunostaining was detectable in 42 (32.1%) of the 131 tumor categories including 24 (18.3%) tumor types with at least one strongly positive case. The highest rate of positive staining was found in various urothelial neoplasms (52.1-92.3%) including Brenner tumor of the ovary (86.8%) and in squamous cell carcinomas from various sites of origin (39.1-77.6%), Warthin tumors of parotid glands (66.7%), adenosquamous carcinomas of the cervix (33.3%), thymomas (16.0%), and endometroid carcinomas of the ovary (15.3%). Twenty other epithelial or germ cell neoplasms showed - a usually weak - CK13 positivity in less than 15% of the cases. In bladder cancer, reduced CK13 expression was linked to high grade and advanced stage (p < 0.0001 each). In squamous cell carcinoma of the cervix, reduced CK13 immunostaining was related to high grade (p = 0.0295) and shortened recurrence-free (p = 0.0094) and overall survival (p = 0.0274). In a combined analysis of 1,151 squamous cell carcinomas from 11 different sites of origin, reduced CK13 staining was linked to high grade (p = 0.0050). Our data provide a comprehensive overview on CK13 expression in normal and neoplastic human tissues. CK13 expression predominates in urothelial neoplasms and in squamous cell carcinomas of different organs, and a loss of CK13 expression is associated with aggressive disease in these tumors.

Desmoglein 3 (Dsg3) expression in cancer: A tissue microarray study on 15,869 tumors.

Desmoglein-3 (Dsg3) is a transmembrane glycoprotein which is preferably found in desmosomes of keratinocytes in squamous epithelium. Both loss and upregulation of Dsg3 have been implicated in cancer progression. To comprehensively evaluate Dsg3 expression in normal and neoplastic tissues, a tissue microarray containing 15,869 samples from 137 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Dsg3 immunostaining was detectable in 47 (34.3 %) tumor categories including 15 (10.9 %) tumor types with at least one strongly positive case. The highest rate of Dsg3 positivity was found in squamous cell carcinomas from various sites (71.2-97.3 %), basal cell carcinomas of the skin (41.9 %), various tumors from salivary glands (12.9-38.9 %), and in urothelial neoplasms (2.1-20.7 %). Dsg3 positivity in less than 10 % of cases was seen in 23 additional cancer categories. Dsg3 staining was almost always weak and rarely moderate in these tumors. High Dsg3 expression was linked to invasive growth in urothelial carcinoma (p < 0.0001), as well as to advanced pT stage (p = 0.0102), nodal metastasis (p = 0.0162), blood vessel infiltration (p = 0.0189) and lymph vessel infiltration (p = 0.0151) in colorectal cancer. Reduced Dsg3 expression was linked to high grade in a cohort of 599 squamous cell carcinomas from 11 different sites of origin (p < 0.0001). Associations between Dsg3 immunostaining and clinicopathological features were not found in invasive breast cancer of no special type, ductal adenocarcinomas of the pancreas and in gastric adenocarcinomas. In summary, Dsg3 expression predominates in squamous cell carcinomas and loss of Dsg3 immunostaining goes along with dedifferentiation of these tumors. The identification of focal squamous differentiation in other neoplasms may constitute a diagnostic application of Dsg3 immunohistochemistry.

Inhibin Alpha Expression in Human Tumors: A Tissue Microarray Study on 12,212 Tumors.

As a result of its expression in corresponding normal cell types, inhibin alpha (INHA) is used as an immunohistochemical marker for adrenocortical neoplasms and testicular or ovarian sex cord stromal tumors. However, other tumors can also express INHA. To comprehensively determine INHA expression in cancer, a tissue microarray containing 15,012 samples from 134 different tumor types and subtypes was analyzed by immunohistochemistry. INHA positivity was found in 72 of 134 tumor categories, including 26 categories with ≥1 strongly positive case. A moderate to strong INHA positivity was found in 100% of 37 granulosa cell tumors of the ovary, 100% of 43 other sex cord stromal tumors of the ovary/testis, 100% of 31 granular cell tumors, 78.5% of 28 adenomas, 44% of 25 carcinomas of the adrenal cortex, and 46.7% of 15 pancreatic acinar cell carcinomas. At least a weak INHA positivity was seen in <33% of cases of 46 additional tumor entities. In summary, these data support the use of INHA antibodies for detecting sex cord stromal tumors, granular cell tumors, and adrenocortical neoplasms. Since INHA can also be found in other tumor entities, INHA immunohistochemistry should only be considered as a part of any panel for the distinction of tumor entities.

Cytokeratin 10 (CK10) expression in cancer: A tissue microarray study on 11,021 tumors.

Cytokeratin 10 (CK10) is a type I acidic low molecular weight cytokeratin which is mainly expressed in keratinizing squamous epithelium of the skin. Variable levels of CK10 protein have been described in squamous carcinomas of different sites and in some other epithelial neoplasms. To comprehensively determine the prevalence of CK10 expression in normal and neoplastic tissues, a tissue microarray containing 11,021 samples from 131 different tumor types and subtypes was analyzed by immunohistochemistry. CK10 immunostaining was detectable in 41 (31.3 %) of 131 tumor categories, including 18 (13.7 %) tumor types with at least one strongly positive case. The highest rate of positive staining was found in squamous cell carcinomas from various sites of origin (positive in 18.6 %-66.1 %) and in Warthin tumors of salivary glands (47.8 %), followed by various tumor entities known to potentially exhibit areas with squamous cell differentiation such as teratomas (33.3 %), basal cell carcinomas of the skin (14.3 %), adenosquamous carcinomas of the cervix (11.1 %), and several categories of urothelial neoplasms (3.1 %-16.8 %). In a combined analysis of 956 squamous cell carcinomas from 11 different sites of origin, reduced CK10 staining was linked to high grade (p < 0.0001) and advanced stage (p = 0.0015) but unrelated to HPV infection. However, CK10 staining was not statistically related to grade (p = 0.1509) and recurrence-free (p = 0.5247) or overall survival (p = 0.5082) in 176 cervical squamous cell carcinomas. In the urinary bladder, CK10 staining occurred more commonly in muscle-invasive (17.7 %) than in non-invasive urothelial carcinomas (4.0 %-6.0 %; p < 0.0001). In summary, our data corroborate a role of CK10 as a suitable marker for mature, keratinizing squamous cell differentiation in epithelial tissues. CK10 immunohistochemistry may thus be instrumental for a more objective evaluation of the clinical significance of focal squamous differentiation in cancer.

Large-scale human tissue analysis identifies Uroplakin 1a as a putative diagnostic marker for urothelial cancer.

Uroplakin 1A (Upk1a) protein is relevant for stabilizing and strengthening urothelial cells and helps to prevent them from rupturing during bladder distension. Based on RNA expression data Upk1a is expressed in a limited number of normal tissues and tumors. To comprehensively evaluate the potential diagnostic and prognostic utility of Upk1a immunohistochemistry, a tissue microarray containing 6929 samples from 115 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed. Upk1a positivity was found in 34 (29.6 %) different tumor types including 9 (7.8 %) tumor types with at least one strongly positive case. The highest rates of Upk1a positivity were seen in various subtypes of urothelial neoplasms (42.6-98 %) including Brenner tumors of the ovary (64.9 %) followed by neoplasms of the thyroid (10.4-33.3 %). In urothelial tumors, Upk1a staining predominated at the cell membranes and staining intensity was often moderate to strong. In thyroidal neoplasms the staining was mostly purely cytoplasmic and of low to moderate intensity. Upk1a positivity was also seen in up to 15 % of cases in 25 additional tumor categories but the staining intensity was often cytoplasmic and the intensity was usually judged as weak and only rarely as moderate. Within non-invasive (pTa) tumors, the Upk1a positivity rate decreased from 94 % in pTa G2 (low grade) to 90.1 % in pTa G3 (p = 0.012) and was even lower in muscle-invasive carcinomas (41.5 %; p < 0.0001 vs pTaG3). Within muscle invasive carcinomas, Upk1a expression was unrelated to nodal metastasis (p > 0.05) and patient outcome (p > 0.05). In conclusion, Upk1a immunohistochemistry is a potentially useful and specific diagnostic marker for the distinction of urothelial carcinomas from other neoplasms. However, its sensitivity is less than 50 % in muscle-invasive cancers because Upk1a expression decreases during grade and stage progression.

Villin expression in human tumors: a tissue microarray study on 14,398 tumors.

BACKGROUND: Villin is a protein of the brush border of epithelial cells, which is used as an immunohistochemical marker for colorectal and gastrointestinal neoplasms. However, other tumor entities can also express villin. METHODS: To comprehensively determine villin expression, tissue microarrays containing 14,398 samples from 118 different tumor types as well as 608 samples of 76 different normal tissues were analyzed by immunohistochemistry. RESULTS: Villin was found in 54 of 118 tumor categories, including 36 tumor categories with strong staining. Villin expression was frequent in colorectal (60-100%), upper gastrointestinal tract (61-100%), pancreatobiliary (25-86%), and renal tumors (≤18%) as well as in mucinous ovarian cancers (67%), yolk sac tumors (76%) and in neuroendocrine neoplasms (22-41%). Reduced villin expression was linked to advanced pT stage, lymph vessel invasion, and microsatellite instability (p ≤ 0.0006) in colorectal adenocarcinoma. CONCLUSION: Our data support a high utility of villin immunohistochemistry for the identification of tumors with gastrointestinal, pancreatobiliary, and yolk sac tumor origin. However, considering that at least a weak villin positivity in some tumor cells occurred in 54 different tumor categories, villin immunohistochemistry should be applied as a part of a marker panel rather than as a stand-alone marker.

Large-scale human tissue analysis identifies Uroplakin 1b as a putative diagnostic marker in surgical pathology.

Uroplakin 1B (Upk1b) stabilizes epithelial cells lining the bladder lumen to prevent rupturing during bladder distension. Little is known about Upk1b expression in other normal and malignant tissues. To comprehensively evaluate the potential diagnostic and prognostic utility of Upk1b expression analysis, a tissue microarray containing 14,061 samples from 127 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Upk1b immunostaining was found in 61 (48%) different tumor types including 50 (39%) with at least one moderately positive and 39 tumor types (31%) with at least one strongly positive tumor. Highest positivity rates were found in urothelial neoplasms (58-95%), Brenner tumors of the ovary (92%), epithelioid mesothelioma (87%), serous carcinoma of the ovary (58%) and the endometrium (53%) as well as in squamous cell carcinoma of the head and neck (18-37%), lung (39%), and esophagus (26%). In urothelial carcinoma, low Upk1b expression was linked to high grade and invasive tumor growth (P < .0001 each) and nodal metastasis (P = .0006). Our data suggest diagnostic applications of Upk1b immunohistochemistry in panels for the distinction of malignant mesothelioma from adenocarcinoma of the lung, urothelial carcinoma from prostatic adenocarcinoma in the bladder, or pancreaticobiliary and gastroesophageal from colorectal adenocarcinoma.

Diagnostic and prognostic impact of cytokeratin 19 expression analysis in human tumors: a tissue microarray study of 13,172 tumors.

To evaluate cytokeratin 19 (CK19) expression in normal and cancerous tissues, 15,977 samples from 122 tumor types and 608 samples of 76 normal tissue types were analyzed by immunohistochemistry (IHC). In normal tissues, CK19 expression occurred in epithelial cells of most glandular organs but was strictly limited to the basal cell layer of nonkeratinizing squamous epithelium and absent in the skin. CK19 expression in ≥90% of cases was seen in 34% of the tumor entities including the adenocarcinomas of the pancreas (99.4%), colorectum (99.8%), esophagus (98.7%), and stomach (97.7%), as well as breast cancer (90.0%-100%), high-grade serous (99.1%) or endometrioid (97.8%) ovarian cancer, and urothelial carcinoma (92.6%-100%). A low CK19 positivity rate (0.1-10%) was seen in 5 of 122 tumor entities including hepatocellular carcinoma and seminoma. A comparison of tumor versus normal tissue findings demonstrated that upregulation and downregulation of CK19 can occur in cancer and that both alterations can be linked to unfavorable phenotypes. CK19 downregulation was linked to high grade (p = 0.0017) and loss of estrogen receptor- and progesterone receptor-expression (p < 0.0001 each) in invasive breast carcinoma of no special type. CK19 upregulation was linked to nodal metastases in neuroendocrine tumors and papillary thyroid carcinomas (p < 0.05 each) and to poor grade in clear cell renal cell carcinoma (p < 0.05). CK19 upregulation was particularly common in squamous cell carcinomas. We concluded that CK19 IHC might separate primary liver cell carcinoma from liver metastases, seminoma from other testicular tumors, and helps in the detection of early neoplastic transformation in squamous epithelium.

Increased Cytoplasmic CD138 Expression Is Associated with Aggressive Characteristics in Prostate Cancer and Is an Independent Predictor for Biochemical Recurrence.

Syndecan-1 (CD138) is a transmembrane proteoglycan expressed in various normal and malignant tissues. It is of interest due to a possible prognostic effect in tumors and its role as a target for the antibody-drug conjugate indatuximab ravtansine. Here, we analyzed 17,747 prostate cancers by immunohistochemistry. Membranous and cytoplasmic CD138 staining was separately recorded. In normal prostate glands, CD138 staining was limited to basal cells. In cancers, membranous CD138 positivity was seen in 19.6% and cytoplasmic CD138 staining in 11.2% of 12,851 interpretable cases. A comparison with clinico-pathological features showed that cytoplasmic CD138 staining was more linked to unfavorable tumor features than membranous staining. Cytoplasmic CD138 immunostaining was associated with high tumor stage (p < 0.0001), high Gleason grade (p < 0.0001), nodal metastases (p < 0.0001), positive surgical margin (p < 0.0001), and biochemical recurrence (p < 0.0001). This also holds true for both V-ets avian erythroblastosis virus E26 oncogene homolog (ERG) fusion positive and ERG fusion negative tumors although the cytoplasmic CD138 expression was markedly more frequent in ERG positive than in ERG negative tumors (p < 0.0001). Comparison with 11 previously analyzed chromosomal deletions identified a conspicuous association between cytoplasmic CD138 expression and 8p deletions (p < 0.0001) suggesting a possible functional interaction of CD138 with one or several 8p genes. Multivariate analysis revealed the cytoplasmic CD138 expression as an independent prognostic parameter in all cancers and in the ERG positive subgroup. In summary, our study indicates the cytoplasmic CD138 expression as a strong and independent predictor of poor prognosis in prostate cancer. Immunohistochemical measurement of CD138 protein may thus-perhaps in combination with other parameters-become clinically useful in the future.

Upregulation of Phosphatase 1 Nuclear-Targeting Subunit (PNUTS) Is an Independent Predictor of Poor Prognosis in Prostate Cancer.

Protein phosphatase 1 nuclear-targeting subunit (PNUTS) is ubiquitously expressed and associates with PTEN and protein phosphatase 1 (PP1) to control its activity. The role of PNUTS overexpression has hardly been studied in cancer. In this study, we used immunohistochemistry to quantitate PNUTS expression on a tissue microarray containing 17,747 clinical prostate cancer specimens. As compared to normal prostate epithelium, PNUTS expression was often higher in cancer. Among 12,235 interpretable tumors, PNUTS staining was negative in 21%, weak in 34%, moderate in 35%, and strong in 10% of cases. High PNUTS expression was associated with higher tumor stage, classical and quantitative Gleason grade, nodal stage, surgical margin, Ki67 labeling index, and early biochemical recurrence (p < 0.0001 each). PNUTS expression proved to be a moderate prognostic parameter with a maximal univariable Cox proportional hazard for PSA recurrence-free survival of 2.21 compared with 5.91 for Gleason grading. It was independent from established prognostic parameters in multivariable analysis. Comparison with molecular data available from earlier studies using the same TMA identified associations between high PNUTS expression and elevated androgen receptor expression (p < 0.0001), presence of TMPRSS2:ERG fusion (p < 0.0001), and 8 of 11 chromosomal deletions (3p13, 5q21, 8p21, 10q23, 12p13, 13q14, 16q24, and 17p13; p < 0.05 each). Particularly strong associations with PTEN and 12p13 deletions (p < 0.0001 each) may indicate a functional relationship, which has already been established for PNUTS and PTEN. PNUTS had no additional role on outcome in PTEN-deleted cancers. In conclusion, the results of our study identify high PNUTS protein levels as a predictor of poor prognosis possibly linked to increased levels of genomic instability. PNUTS measurement, either alone or in combination, might be of clinical utility in prostate cancers.

High CHK2 protein expression is a strong and independent prognostic feature in ERG negative prostate cancer.

Checkpoint kinase 2 (CHK2) is a serine-threonine kinase with a role in DNA repair, cell cycle arrest or apoptosis in response to DNA damage. Both reduced and increased CHK2 expression has been described in different tumour types with impact on patient prognosis. To evaluate prevalence and significance of altered CHK2 expression in prostate cancer, a tissue microarray containing 17,747 tumours was analysed by immunohistochemistry. Nuclear CHK2 immunostaining was absent or weak in benign prostate epithelium but often more prominent in cancers. CHK2 immunostaining was considered weak in 38.8%, moderate in 33.6% and strong in 11.2% of prostate cancers. High CHK2 expression was strongly associated with TMPRSS2:ERG fusions (p<0.0001). Subgroup analysis of ERG positive and negative cancers revealed that high CHK2 staining was significantly linked to advanced tumour stage, high Gleason score, positive nodal status, positive surgical margin, high preoperative PSA (p<0.0001 each) and early prostate-specific antigen (PSA) recurrence (p=0.0001) in the subset of ERG negative cancers, while most of these associations were absent in ERG positive cancers. In ERG negative cancers, high CHK2 expression was an independent predictor of patient prognosis, even if parameters were included that were only available postoperatively. High CHK2 expression was also linked to presence of chromosomal deletions, high level of androgen receptor expression, positive p53 immunostaining, and high Ki-67 labelling index. These provide further in vivo evidence for previously described functional interactions. In summary, high CHK2 expression is linked to adverse tumour features and independently predicts early biochemical recurrence in ERG negative prostate cancer. CHK2 measurement, either alone or in combination, might be of clinical utility in this prostate cancer subgroup.

Upregulation of PTTG1 is associated with poor prognosis in prostate cancer.

Pituitary tumor-transforming gene 1 (PTTG1) is a regulator of chromosome stability. PTTG1 overexpression had been associated with tumor aggressiveness in several cancer types. To examine its prognostic utility in prostate cancer, a tissue microarray including 12 427 tumors with clinical and molecular data was analyzed by immunohistochemistry. PTTG1 immunostaining was largely absent in normal prostate epithelial cells. In cancers, staining was considered weak in 5.4%, moderate in 5.6% and strong in 0.8%. Strong staining was linked to advanced pT stage, high classical and quantitative Gleason grade, high Ki67-labeling index (all P < 0.0001) and lymph node metastasis (P = 0.0083). The prognostic impact of PTTG1 expression was independent of established preoperative and postoperative prognostic features. Comparison with molecular features revealed that PTTG1 upregulation was associated with nine of 12 common genomic deletions (P < 0.05), p53 alterations and high androgen receptor levels (P < 0.001 each), but was unrelated to the TMPRSS2:ERG fusion status. In conclusion, these data identify PTTG1 as a strong and independent prognostic feature in prostate cancer. PTTG1 measurement, either alone or in combination with other biomarkers might be instrumental for determining prostate cancer aggressiveness.

Upregulation of the transcription factor TFAP2D is associated with aggressive tumor phenotype in prostate cancer lacking the TMPRSS2:ERG fusion.

BACKGROUND: TFAP2D is a transcription factor important for modulating gene expression in embryogenesis. Its expression and prognostic role in prostate cancer has not been evaluated. METHODS: Therefore, a tissue microarray containing 17,747 prostate cancer specimens with associated pathological, clinical, and molecular data was analyzed by immunohistochemistry to assess the role of TFAP2D. RESULTS: TFAP2D expression was typically increased in prostate cancer as compared to adjacent non-neoplastic glands. TFAP2D staining was considered negative in 24.3% and positive in 75.7% of 13,545 interpretable cancers. TFAP2D staining was significantly linked to advanced tumor stage, high classical and quantitative Gleason grade, lymph node metastasis, and a positive surgical margin (p ≤ 0.0045). TFAP2D positivity was more common in ERG fusion positive (88.7%) than in ERG negative cancers (66.8%; p < 0.0001). Subset analyses in 3776 cancers with and 4722 cancers without TMPRSS2:ERG fusion revealed that associations with tumor phenotype and patient outcome were largely driven by the subset of ERG negative tumors. Multivariate analysis did not identify TFAP2D protein expression levels as a robust independent prognostic parameter. Positive TFAP2D immunostaining was significantly associated with 10 of 11 previously analyzed chromosomal deletions in ERG negative cancers (p ≤ 0.0244 each) indicating that elevated TFAP2D expression parallels genomic instability in prostate cancer. CONCLUSION: These data demonstrate that TFAP2D protein overexpression is linked to prostate cancer progression and genomic instability in ERG negative prostate cancers.