Automated Ki-67 labeling index assessment in prostate cancer using artificial intelligence and multiplex fluorescence immunohistochemistry.

The Ki-67 labeling index (Ki-67 LI) is a strong prognostic marker in prostate cancer, although its analysis requires cumbersome manual quantification of Ki-67 immunostaining in 200-500 tumor cells. To enable automated Ki-67 LI assessment in routine clinical practice, a framework for automated Ki-67 LI quantification, which comprises three different artificial intelligence analysis steps and an algorithm for cell-distance analysis of multiplex fluorescence immunohistochemistry (mfIHC) staining, was developed and validated in a cohort of 12,475 prostate cancers. The prognostic impact of the Ki-67 LI was tested on a tissue microarray (TMA) containing one 0.6 mm sample per patient. A 'heterogeneity TMA' containing three to six samples from different tumor areas in each patient was used to model Ki-67 analysis of multiple different biopsies, and 30 prostate biopsies were analyzed to compare a 'classical' bright field-based Ki-67 analysis with the mfIHC-based framework. The Ki-67 LI provided strong and independent prognostic information in 11,845 analyzed prostate cancers (p < 0.001 each), and excellent agreement was found between the framework for automated Ki-67 LI assessment and the manual quantification in prostate biopsies from routine clinical practice (intraclass correlation coefficient: 0.94 [95% confidence interval: 0.87-0.97]). The analysis of the heterogeneity TMA revealed that the Ki-67 LI of the sample with the highest Gleason score (area under the curve [AUC]: 0.68) was as prognostic as the mean Ki-67 LI of all six foci (AUC: 0.71 [p = 0.24]). The combined analysis of the Ki-67 LI and Gleason score obtained on identical tissue spots showed that the Ki-67 LI added significant additional prognostic information in case of classical International Society of Urological Pathology grades (AUC: 0.82 [p = 0.002]) and quantitative Gleason score (AUC: 0.83 [p = 0.018]). The Ki-67 LI is a powerful prognostic parameter in prostate cancer that is now applicable in routine clinical practice. In the case of multiple cancer-positive biopsies, the sole automated analysis of the worst biopsy was sufficient. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Nonredundant Upregulation of CD112R (PVRIG) and PD-1 on Cytotoxic T Lymphocytes Located in T Cell Nests of Colorectal Cancer.

Focal T lymphocyte aggregates commonly occur in colorectal cancer; however, their biological significance is unknown. To study focal aggregates of T lymphocytes, a deep learning-based framework for automated identification of T cell accumulations (T cell nests) was developed using CD8, PD-1, CD112R, and Ki67 multiplex fluorescence immunohistochemistry. To evaluate the clinical significance of these parameters, a cohort of 523 colorectal cancers with clinical follow-up data was analyzed. Spatial analysis of locally enriched CD8+ T cell density and cell-to-cell contacts identified T cell nests in the tumor microenvironment of colorectal cancer. CD112R and PD-1 expressions on CD8+ T cells located in T cell nests were found to be elevated compared with those on CD8+ T cells in all other tumor compartments (P < .001 each). Although the highest mean CD112R expression on CD8+ T cells was observed at the invasive margin, the PD-1 expression on CD8+ T cells was elevated in the center of the tumor (P < .001 each). Across all tissue compartments, proliferating CD8+ T cells showed higher relative CD112R and PD-1 expressions than those shown by non-proliferating CD8+ T cells (P < .001 each). Integration of all available spatial and immune checkpoint expression parameters revealed a superior predictive performance for overall survival (area under the curve, 0.65; 95% CI, 0.60-0.70) compared with the commonly used CD8+ tumor-infiltrating lymphocyte density (area under the curve, 0.57; 95% CI, 0.53-0.61; P < .001). Cytotoxic T cells with elevated CD112R and PD-1 expression levels are orchestrated in T cell nests of colorectal cancer and predict favorable patient outcomes, and the spatial nonredundancy underlies fundamental differences between both inhibitory immune checkpoints that provide a rationale for dual anti-CD112R/PD-1 immune checkpoint therapy.

GATA3 Expression in Human Tumors: A Tissue Microarray Study on 16,557 Tumors.

INTRODUCTION: GATA3 is a transcription factor involved in epithelial cell differentiation. GATA3 immunostaining is used as a diagnostic marker for breast and urothelial cancer but can also occur in other neoplasms. METHODS: To evaluate GATA3 in normal and tumor tissues, a tissue microarray containing 16,557 samples from 131 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. RESULTS: GATA3 positivity was found in 69 different tumor types including 23 types (18%) with at least one strongly positive tumor. Highest positivity rates occurred in noninvasive papillary urothelial carcinoma (92-99%), lobular carcinoma (98%), carcinoma of no special type of the breast (92%), basal cell carcinoma of the skin (97%), invasive urothelial carcinoma (73%), T-cell lymphoma (23%), adenocarcinoma of the salivary gland (16%), squamous cell carcinoma of the skin (16%), and colorectal neuroendocrine carcinoma (12%). In breast cancer, low GATA3 staining was linked to high pT stage (p = 0.03), high BRE grade (p < 0.0001), HER2 overexpression (p = 0.0085), estrogen and progesterone receptor negativity (p < 0.0001 each), and reduced survival (p = 0.03). CONCLUSION: Our data demonstrate that GATA3 positivity can occur in various tumor entities. Low levels of GATA3 reflect cancer progression and poor patient prognosis in breast cancer.

Regeneration of the entire human epidermis using transgenic stem cells.

Junctional epidermolysis bullosa (JEB) is a severe and often lethal genetic disease caused by mutations in genes encoding the basement membrane component laminin-332. Surviving patients with JEB develop chronic wounds to the skin and mucosa, which impair their quality of life and lead to skin cancer. Here we show that autologous transgenic keratinocyte cultures regenerated an entire, fully functional epidermis on a seven-year-old child suffering from a devastating, life-threatening form of JEB. The proviral integration pattern was maintained in vivo and epidermal renewal did not cause any clonal selection. Clonal tracing showed that the human epidermis is sustained not by equipotent progenitors, but by a limited number of long-lived stem cells, detected as holoclones, that can extensively self-renew in vitro and in vivo and produce progenitors that replenish terminally differentiated keratinocytes. This study provides a blueprint that can be applied to other stem cell-mediated combined ex vivo cell and gene therapies.

Pattern of MUC6 expression across 119 different tumor types: A tissue microarray study on 15 412 tumors.

Mucin 6 (MUC6) is a secreted gel-forming mucin covering the surfaces of gastrointestinal and other tissues. Published work demonstrates that MUC6 can also be expressed in several cancer types and can aid in the distinction of different tumor entities. To systematically analyze MUC6 expression in normal and cancerous tissues, a tissue microarray containing 15 412 samples from 119 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. At least a weak MUC6 positivity was seen in 50 of 119 (42%) tumor entities. Thirty-three tumor entities included tumors with strong positivity. MUC6 immunostaining was most frequent in mucinous carcinomas of the breast (44%), adenocarcinomas of the stomach (30%-40%) and esophagus (35%), and neuroendocrine carcinomas of the colon. Strong MUC6 staining was linked to advanced pT stage (p = 0.0464), defective mismatch repair status and right-sided tumor location (p < 0.0001 each) in colorectal cancer, as well as to high tumor grade (p = 0.0291), nodal metastasis (p = 0.0485), erb-b2 receptor tyrosine kinase 2 positivity (p < 0.0001) and negative estrogen receptor (p = 0.0332)/progesterone receptor (p = 0.0257) status in breast carcinomas of no special type. The broad range of tumor types with MUC6 expression limits the utility of MUC6 immunohistochemistry for the distinction of different tumor types.

Semi-automated validation and quantification of CTLA-4 in 90 different tumor entities using multiple antibodies and artificial intelligence.

CTLA-4 is an inhibitory immune checkpoint receptor and a negative regulator of anti-tumor T-cell function. This study is aimed for a comparative analysis of CTLA-4+ cells between different tumor entities. To quantify CTLA-4+ cells, 4582 tumor samples from 90 different tumor entities as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry in a tissue microarray format. Two different antibody clones (MSVA-152R and CAL49) were validated and quantified using a deep learning framework for automated exclusion of unspecific immunostaining. Comparing both CTLA-4 antibodies revealed a clone dependent unspecific staining pattern in adrenal cortical adenoma (63%) for MSVA-152R and in pheochromocytoma (67%) as well as hepatocellular carcinoma (36%) for CAL49. After automated exclusion of non-specific staining reaction (3.6%), a strong correlation was observed for the densities of CTLA-4+ lymphocytes obtained by both antibodies (r = 0.87; p < 0.0001). A high CTLA-4+ cell density was linked to low pT category (p < 0.0001), absent lymph node metastases (p = 0.0354), and PD-L1 expression in tumor cells or inflammatory cells (p < 0.0001 each). A high CTLA-4/CD3-ratio was linked to absent lymph node metastases (p = 0.0295) and to PD-L1 positivity on immune cells (p = 0.0026). Marked differences exist in the number of CTLA-4+ lymphocytes between tumors. Analyzing two independent antibodies by a deep learning framework can facilitate automated quantification of immunohistochemically analyzed target proteins such as CTLA-4.

Cytokeratin 7 and cytokeratin 20 expression in cancer: A tissue microarray study on 15,424 cancers.

Combined analysis of cytokeratin 7 (CK7) and cytokeratin 20 (CK20) is often used for assessing the origin of metastatic cancer. To evaluate the diagnostic utility of CK7 and CK20, tissue microarrays containing 15,424 samples from 120 different tumor types and subtypes and 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. CK7 positivity was seen in 52% (8.7% weak, 5.9% moderate, 37% strong) and CK20 positivity in 23% (5.1% weak, 3.4% moderate, 15% strong) of interpretable tumors. Of 8390 positive tumors, 1181 (14%) showed positivity for CK7 and CK20, 5380 (64%) showed positivity for CK7 alone, and 1829 (22%) showed positivity for CK20 alone. CK20 predominated in gastrointestinal tract, urothelial and Merkel cell carcinomas. CK7 was usually negative in prostate cancer and colorectal cancer. Combined evaluation of CK7/CK20 revealed the best diagnostic utility in CK20 positive tumors, where CK7 negativity is often linked to colorectal origin while CK7 positivity argues for urothelial origin or mucinous ovarian cancer. Associations with unfavorable tumor features were found for cytokeratin 7 loss in breast cancer of no special type, urothelial and renal cell carcinomas, for CK7 overexpression in high-grade serous ovarian and gastric cancer, and for CK20 overexpression in urothelial carcinoma. CK20 loss was linked to MSI in gastric (p = 0.0291) and colorectal adenocarcinoma (p < 0.0001). These analyses provide comprehensive data on the frequency of CK7 and CK20 immunostaining - alone or in combination - in human cancers. These data facilitate interpretation of CK7/CK20 immunostaining in cancers.

Trophoblast Cell Surface Antigen 2 Expression in Human Tumors: A Tissue Microarray Study on 18,563 Tumors.

INTRODUCTION: Trophoblast cell surface antigen 2 (TROP2) is the target of sacituzumab govitecan, an antibody-drug conjugate approved for treatment of triple negative breast cancer and urothelial carcinoma. METHODS: A tissue microarray containing 18,563 samples from 150 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by TROP2 immunohistochemistry. RESULTS: TROP2 positivity was found in 109 tumor categories, including squamous cell carcinomas of various origins, urothelial, breast, prostate, pancreatic, and ovarian cancers (>95% positive). High TROP2 expression was linked to advanced stage (p = 0.0069) and nodal metastasis (p < 0.0001) in colorectal cancer as well as to nodal metastasis in gastric adenocarcinoma (p = 0.0246) and papillary thyroid cancer (p = 0.0013). Low TROP2 expression was linked to advanced stage in urothelial carcinoma (p < 0.0001), high pT (p = 0.0024), and high grade (p < 0.0001) in breast cancer, as well as with high Fuhrmann grade (p < 0.0001) and pT stage (p = 0.0009) in papillary renal cell carcinomas. CONCLUSION: TROP2 is expressed in many epithelial neoplasms. TROP2 deregulation can be associated with cancer progression in a tumor-type dependent manner. Since anti-TROP2 cancer drugs have demonstrated efficiency, they may be applicable to a broad range of tumor entities in the future.

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.

Clinicopathological findings in patients with COVID-19-associated ischaemic enterocolitis.

AIMS: Coronavirus disease 2019 (COVID-19) has been recognised as a predominantly respiratory tract infection, but some patients manifest severe systemic symptoms/coagulation abnormalities. The aim of this study was to evaluate the impact of severe COVID-19 infection on the gastrointestinal tract. METHODS AND RESULTS: We examined clinicopathological findings in 28 resected ischaemic bowels from 22 patients with severe COVID-19. Most patients required intubation preoperatively and presented with acute decompensation shortly before surgery. D-dimer levels were markedly elevated in all measured cases (mean, 5394 ng/ml). Histologically, 25 cases (19 patients) showed evidence of acute ischaemia with necrosis. In this group, the most characteristic finding was the presence of small vessel fibrin thrombi (24 of 25 cases, 96%), which were numerous in 64% of cases. Patients with COVID-19 were significantly more likely than a control cohort of 35 non-COVID-19-associated acute ischaemic bowels to show isolated small intestine involvement (32% versus 6%, P < 0.001), small vessel fibrin thrombi (100% versus 43%, P < 0.001), submucosal vessels with fibrinous degeneration and perivascular neutrophils (90% versus 54%, P < 0.001), fibrin strands within submucosal vessels (58% versus 20%, P = 0.007), and histological evidence of pneumatosis (74% versus 34%, P = 0.010). Three cases in this cohort had histopathological findings normally seen in the setting of chronic ischaemia, notably prominent fibroblastic proliferation affecting the outer layer of the muscularis propria. CONCLUSIONS: Herein, we describe the histopathological findings in COVID-19-associated ischaemic bowels and postulate a relationship with the hypercoagulable state seen in patients with severe COVID-19 infection. Additional experience with these cases may further elucidate specific features or mechanisms of COVID-19-associated ischaemic enterocolitis.

Mesothelin is Commonly Expressed in Pancreatic Adenocarcinoma but Unrelated to Cancer Aggressiveness.

Data on Mesothelin (MSLN) expression in human normal and cancerous tissues is controversial. We employed immunohistochemistry (IHC) on a tissue microarray (TMA) from 599 pancreatic cancers and 12 large tissue sections of pancreatitis. MSLN expression was highest in pancreatic adenocarcinomas (89%) and adenocarcinomas of the ampulla Vateri (79%), infrequent in pancreatitis and absent in 6 acinus cell carcinomas and normal pancreas. MSLN expression was unrelated to pathological tumor stage, grade, metastasis, and tumor-infiltrating CD8+ lymphocytes. In conclusion, pancreatic cancer may be ideally suited for putative anti- MSLN therapies, and MSLN may represent a suitable biomarker for pancreatic cancer diagnosis, especially on small biopsies.

An Unusual Case of Iron-Deficiency Anemia: The Culprit Hides in the Aorta.

In a 72-year-old patient with anemia (Hb 7 g/dl), duodenoscopy exhibited an area of polypous irregular-looking mucosa. Histology revealed duodenal infiltration by epithelioid tumor cells, immunhistochemically positive for endothelial cell markers (CD34, CD31, ERG). Ultrasonography showed thrombotic material in the otherwise unremarkable abdominal aorta with some uptake of contrast bubbles on CEUS. Histological and clinical diagnosis assumed an epithelioid angiosarcoma of the thoraco-abdominal aorta at the level of the visceral and renal arteries with duodenal metastases.To prevent further shedding of tumor cells and aortic rupture, a branched stent-graft was placed into the thoraco-abdominal aorta. Palliative chemotherapy with gemcitabine and docetaxel was started, leading to a partial remission after 6 cycles. Three months later, however, there was a progress of the duodenal masses with new pulmonal and osseous metastases. Thirteen months after the initial diagnosis, death occured due to a hemorrhagic shock caused by a hematothorax.Aortic tumors are exceedingly rare, with only slightly more than 220 cases reported so far. In most cases, diagnosis is made either at autopsy or after an emergency operation for embolic complications like embolic intestinal ischemia. With an overall median survival of 8 months, prognosis is very poor.This case sensitizes for the correct sonographic interpretation of aortic "thrombi" in an otherwise normally appearing aorta, possibly with the aid of CEUS. Besides, it demonstrates the relatively early and uncommon diagnosis of an aortic angiosarcoma by the combination of endoscopy, immunohistochemistry, and ultrasonography.

Immunohistochemically detectable thyroglobulin expression in extrathyroidal cancer is 100% specific for thyroidal tumor origin.

Thyroglobulin is a secreted 660 kDa glycoprotein produced by thyroid follicular cells used in diagnostic pathology to secure or exclude a thyroidal origin of metastases of unknown primary tumors. This study was performed to estimate specificity of thyroglobulin immunohistochemistry. 9974 tumor samples from 109 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry in a tissue microarray format. Thyroglobulin was strongly expressed in all normal thyroid samples but not in any other normal tissues. Thyroglobulin immunostaining was detected in 99.1% of 106 thyroid adenomas, 98.1% of 364 papillary, 95.2% of 147 follicular, and 7.5% of 40 anaplastic thyroid cancers. Twelve of 15 thyroid samples that were thyroglobulin negative on TMAs showed at least a weak focal thyroglobulin positivity in corresponding large sections, suggesting higher sensitivity of large section analysis. Thyroglobulin positivity in one diffuse large B-cell lymphoma of the thyroid, one chondrosarcoma metastasis to the thyroid, and 42.4% of 92 medullary thyroid cancers was considered to be caused by diffusion of thyroidal colloid from destroyed or even intact adjacent follicles. Thyroglobulin positivity was, however, not seen in 6403 extrathyroidal tumors from 104 different tumor types and subtypes. Our data demonstrate a complete specificity of positive thyroglobulin immunostaining for thyroid origin in tumor tissues obtained from extrathyroidal locations. However, for all tumors located within the thyroid, false positivity can occur as a result of tissue contamination by thyroglobulin rich thyroid colloid from adjacent normal tissue.

Chaperones in sporadic inclusion body myositis-Validation of proteomic data.

INTRODUCTION: Sporadic inclusion body myositis (sIBM) is characterized by myopathological features including rimmed vacuoles (RVs) and proteins associated with protein aggregation, autophagy, and inflammation. Previous proteomic studies of RV areas revealed an overrepresentation of several chaperones and subunits of the T-complex protein 1 (TCP-1), which is involved in prevention of protein aggregation. METHODS: To validate our proteomic findings, immunofluorescence analyses of selected chaperones and quantitative Western blot analysis of TCP-1 proteins were performed in five sIBM patients and five healthy controls. RESULTS: Immunofluorescence studies confirmed increased immunoreactivity for VCP, UNC45B, GRP-75, αB-crystallin, LAMP-2, Rab-7a, and TCP-1α and TCP-θ in RVs. Quantitative Western blot analysis revealed a significantly higher level of TCP-1 in sIBM muscle tissue when compared with healthy controls. DISCUSSION: Our study findings validate new insights in protein quality control and degradation processes that seem to be relevant in sIBM. These data provide an important basis for future functional and therapeutic studies.

High RSF1 protein expression is an independent prognostic feature in prostate cancer.

Background: Remodelling and spacing factor 1 (RSF1) is involved in the regulation of chromatin remodelling and represents a potential therapeutic target. High RSF1 expression has been linked to adverse tumour features in many cancer types, but its role in prostate cancer is uncertain.Methods: In this study, RSF1 expression was analysed by immunohistochemistry on a tissue microarray with 17,747 prostate cancers.Results: Nuclear RSF1 staining of 16,456 interpetable cancers was considered strong, moderate, weak and negative in 25.2%, 48.7%, 5.3% and 20.8% of cancers respectively. Positive RSF1 expression was associated with advanced tumour stage, high Gleason grade, lymph node metastasis (p < .0001 each), early biochemical recurrence (p < .0003) and more frequent in the ERG positive than in the ERG negative subset (88% versus 71%; p < .0001). Subset analysis revealed, that associations between RSF1 expression and unfavourable tumour phenotype and PSA recurrence were present in both subgroups but stronger in the ERG negative than in the ERG positive subset. The univariate Cox proportional hazard ratio for PSA recurrence-free survival for strong versus negative RSF1 expression was a weak 1.60 compared with 5.91 for the biopsy Gleason grade ≥4 + 4 versus ≤3 + 3. The positive association of RSF1 protein detection with deletion of 3p13, 10q23 (PTEN), 12p13, 16q23, and 17p13 (p < .0001 each) suggest a role of high RSF1 expression in the development of genomic instability.Conclusion: In summary, the results of our study identify RSF1 as an independent prognostic marker in prostate cancer with a particularly strong role in ERG negative cases.

5q21 deletion is often heterogeneous in prostate cancer.

Cancer heterogeneity represents a challenge for the analysis of prognostic molecular markers but can be used to study the evolution of molecular events in tumors. To assess the degree of heterogeneity of 5q21 deletions and their relationship with TMPRSS2:ERG status and 6q15 deletions in prostate cancer, a heterogeneity tissue microarray including 10 tissue spots from 10 different areas of 317 cancers was analyzed by fluorescence in situ hybridization for 5q21 deletion. Data on 6q and ERG were available from earlier studies. Deletions of 5q21 were found in 23% of 265 interpretable cancers and showed marked intratumoral heterogeneity. In the subset of 246 cancers with at least 3 interpretable spots, 23% had a 5q21 deletion. Heterogeneous 5q21 deletions were found in 71% and homogeneous in 29% of these cancers. The likelihood of 5q21 deletion was twice as high in ERG-negative (28%) than in ERG-positive cancers (16%, P = .024). In all 21 cases harboring both alterations, the tumor area containing a 5q21 deletion was smaller or equally large than the ERG-positive area but never larger. Deletions of 5q and 6q were significantly linked. However, the analysis of 32 tumors harboring both deletions did not suggest a specific order of appearance of these deletions. The 5q21 deletion preceded 6q15 in 10 tumors and 6q15 preceded 5q21 in 14 tumors. In summary, our study identifies 5q21 deletion as a highly heterogeneous aberration in prostate cancer that usually occurs late during cancer progression. This is a severe limitation for using 5q21 testing as a prognostic tool.

Loss of CCAAT-enhancer-binding protein alpha (CEBPA) is linked to poor prognosis in PTEN deleted and TMPRSS2:ERG fusion type prostate cancers.

BACKGROUND: The transcription factor CCAAT-enhancer-binding protein alpha (CEBPA) is a crucial regulator of cell proliferation and differentiation. Expression levels of CEBPA have been suggested to be prognostic in various tumor types. METHODS: Here, we analyzed the immunohistochemical expression of CEBPA in a tissue microarray containing more than 17 000 prostate cancer specimens with annotated clinical and molecular data including for example TMPRSS2:ERG fusion and PTEN deletion status. RESULTS: Normal prostate glands showed moderate to strong CEBPA staining, while CEBPA expression was frequently reduced (40%) or lost (30%) in prostate cancers. Absence of detectable CEBPA expression was markedly more frequent in ERG negative (45%) as compared to ERG positive cancers (20%, P < 0.0001). Reduced CEBPA expression was linked to unfavorable phenotype (P < 0.0001) and poor prognosis (P = 0.0008). Subgroup analyses revealed, that the prognostic value of CEBPA loss was entirely driven by tumors carrying both TMPRSS2:ERG fusions and PTEN deletions. In this subgroup, CEBPA loss was tightly linked to advanced tumor stage (P < 0.0001), high Gleason grade (P < 0.0001), positive nodal stage (0.0003), and early biochemical recurrence (P = 0.0007), while these associations were absent or markedly diminished in tumors with normal PTEN copy numbers and/or absence of ERG fusion. CONCLUSIONS: CEBPA is down regulated in about one third of prostate cancers, but the clinical impact of CEBPA loss is strictly limited to the subset of about 10% prostate cancers carrying both ERG fusion and deletions of the PTEN tumor suppressor. Our findings challenge the concept that prognostic molecular markers may be generally applicable to all prostate cancers.

The independent prognostic impact of the GATA2 pioneering factor is restricted to ERG-negative prostate cancer.

GATA2 is a pioneering transcription factor governing androgen receptor expression and signaling in prostate cells. To understand the prognostic potential of GATA2 assessment in prostate cancer, we analyzed nuclear GATA2 expression on an annotated tissue microarray with 12,427 prostate cancer samples. Normal prostate glands were negative to weakly positive. GATA2 staining was found in almost all prostate cancers (95%). Strong GATA2 staining was linked to advanced tumor stage, high classical and quantitative Gleason grade (p < 0.0001 each), positive nodal stage (p = 0.0116), and early biochemical recurrence (p < 0.0001). GATA2 was linked to ERG-fusion-type cancers, with strong GATA2 staining in 29% of ERG-negative and 53% of ERG-positive cancers (p < 0.0001). Separate calculations in 3854 cancers with and 4768 cancers without TMPRSS2:ERG fusion revealed that these associations with tumor phenotype and patient outcome were largely driven by the subset of ERG-negative tumors. GATA2 expression was further linked to androgen receptor expression: Only 8% of androgen receptor-negative, but 56% of strongly androgen receptor expressing cancers had strong GATA2 expression (p < 0.0001). In conclusion, the results of our study demonstrate that increasing GATA2 levels are linked to prostate cancer progression and aggressiveness. The prognostic value of GATA2 is remarkable in ERG-negative cancers. However, the upregulation of GATA2 in ERG-positive cancers makes it unsuitable as a prognostic marker in this patient subset.

Aberrant expression of the microtubule-associated protein tau is an independent prognostic feature in prostate cancer.

BACKGROUND: Microtubule-associated protein Tau (MAPT) overexpression has been linked to poor prognosis and decreased response to taxane-based therapies in several cancer types, but its relevance in prostate cancer is unknown. METHODS: In this study, MAPT expression was analyzed by immunohistochemistry on a tissue microarray containing 17,747 prostate cancers. RESULTS: MAPT was absent in normal prostate epithelial cells but detectable in 1004 (8.2%) of 12,313 interpretable cancers. Its expression was associated with advanced tumor stage, high Gleason grade, positive lymph nodes, and early biochemical recurrence (p < 0.0001 each). For example, MAPT was found in 3.6% of 2072 Gleason ≤3 + 3 cancers but in 14.4% of 704 Gleason ≥4 + 4 cancers. High-level MAPT staining was also linked to TMPRSS2:ERG fusions (p < 0.0001). MAPT staining was seen in 15.2 and 16% of cancers with TMPRSS2:ERG fusion detected by immunohistochemistry and fluorescence in-situ hybridization, but in only 3.5 and 3.9% of cancers without ERG staining or ERG rearrangements. Moreover, an association was found between MAPT expression and PTEN deletions, with 19% MAPT positivity in 948 PTEN deleted cancers but only 7% MAPT positivity in 3895 tumors with normal PTEN copy numbers (p < 0.0001). Multivariate analysis revealed that the prognostic value of MAPT was independent from established parameters. Conventional large section analyses showed intratumoral MAPT heterogeneity in all three analyzed cancers. CONCLUSIONS: The results of our study identify MAPT, as a moderate prognostic marker in prostate cancer, whose clinical impact, however, may be limited due to the rarity and heterogeneity of its expression.

Reduced RBM3 expression is associated with aggressive tumor features in esophageal cancer but not significantly linked to patient outcome.

BACKGROUND: RBM3 expression has been suggested as prognostic marker in several cancer types. The purpose of this study was to assess the prevalence and clinical significance of altered RBM3 expression in esophageal cancer. METHODS: RBM3 protein expression was measured by immunohistochemistry using tissue microarrays containing samples from 359 esophageal adenocarcinoma (EAC) and 254 esophageal squamous cell cancer (ESCC) patients with oncological follow-up data. RESULTS: While nuclear RBM3 expression was always high in benign esophageal epithelium, high RBM3 expression was only detectable in 66.4% of interpretable EACs and 59.3% of ESCCs. Decreased RBM3 expression was linked to a subset of EACs with advanced UICC stage and presence of distant metastasis (P = 0.0031 and P = 0.0024). In ESCC, decreased RBM3 expression was associated with advanced UICC stage, high tumor stage, and positive lymph node status (P = 0.0213, P = 0.0061, and P = 0.0192). However, RBM3 expression was largely unrelated to survival of patients with esophageal cancer (EAC: P = 0.212 and ESCC: P = 0.5992). CONCLUSIONS: In summary, the present study shows that decreased RBM3 expression is associated with unfavourable esophageal cancer phenotype, but not significantly linked to patient prognosis.