Multiplatform computational analysis of mast cells in adrenocortical carcinoma tumor microenvironment.

BACKGROUND: Immunotherapeutic response failure of adrenocortical carcinomas highlights a need for novel strategies targeting immune cell populations in the tumor microenvironment to overcome tumor resistance and enhance therapeutic response. A recent study explored a new link between tumor mast cell infiltration and improved outcomes in patients with adrenocortical carcinomas. We further dissect the role of mast cells in the tumor microenvironment of adrenocortical carcinomas by examining the tumor mast cell expression signatures and mast cell activity within the tumor microenvironment to provide additional insight into potential novel immunotherapeutic targets. METHODS: Using the CIBERSORTx computational immunogenomic deconvolution algorithm to analyze adrenocortical carcinoma tumor gene messenger RNA expression data (The Cancer Genome Atlas, N = 79), we estimated the abundance of tumor immune infiltrating mast cells and assessed prognostic potential of mast cell signaling genes as pro or antitumor signatures, as well as examined the impact on overall and disease-free survival. RESULTS: We stratified mast cell signaling genes with survival prognostic values (overall survival, disease-free survival, P < .05) into antitumor (ALOX5, CCL2, CCL5, CXCL10, HDC, IL16, TNF, TPSAB1, VEGFD) and protumor (CXCL1, CXCL3, CXCL8, IL4, IL13, PTGS3, TNSF4, VEGFD) groups. Antitumor mast cell signature, as the predominant phenotype, was associated with improved overall and disease-free survival. CONCLUSION: The deconvolution analysis of The Cancer Genome Atlas data identified mast cell infiltration in the adrenocortical carcinoma microenvironment as predominantly associated with antitumor activity. Future studies stemming from our findings may help define the role of mast cells in the tumor microenvironment and the impact on patient survival in patients with adrenocortical carcinomas. Modulation of tumor mast cell infiltration may serve as a potential target for novel synergistic immunotherapies for the treatment and improved survival of patients with adrenocortical carcinomas.

MSI2 expression in adrenocortical carcinoma: Association with unfavorable prognosis and correlation with steroid and immune-related pathways.

Adrenocortical carcinoma (ACC) is a rare, but highly aggressive cancer of the adrenal cortex with a generally poor prognosis. Despite being rare, completely resected ACCs present a high risk of recurrence. Musashi-2 (MSI2) has recently been recognized as a potential prognostic biomarker and therapeutic target in many cancers. However, no studies have evaluated the clinical significance of MSI2 expression in ACC. Here, we addressed MSI2 expression and its association with ACC prognosis and clinicopathological parameters. MSI2 expression was analyzed in TCGA, GSE12368, GSE33371, and GSE49278 ACC datasets; and its correlation with other genes and immune cell infiltration were investigated by using the R2: Genomics Analysis and Visualization Platform and TIMER databases, respectively. Enrichment analysis was performed with the DAVID Functional Annotation Tool. Kaplan-Meier curves, log-rank tests, and Cox regression analyses were used to explore the prognostic role of MSI2 in ACC. Our findings demonstrated the potential value of MSI2 overexpression as an independent predictor of poor prognosis in patients with completely resected ACC (hazard ratio 6.715, 95% confidence interval 1.266 - 35.620, p =.025). In addition, MSI2 overexpression was associated with characteristics of unfavorable prognosis, such as cortisol excess (p = .002), recurrence (p =.003), and death (p =.015); positively correlated with genes related to steroid biosynthesis (p < .05); and negatively correlated with immune-related pathways (p < .05). Our findings demonstrate that MSI2 has value as a prognostic marker for completely resected ACC and reinforce the investigation of its role as a possible therapeutic target for patients with ACC.

Emerging drugs for the treatment of adrenocortical carcinoma.

Introduction: Adrenocortical cancer (ACC) is a rare and aggressive disease with a median survival of 14-17 months and 5-year survival of around 20% for advanced disease. Emerging evidence of sub-groups of ACC with specific molecular drivers indicate ACC may be amenable to inhibition of receptor tyrosine kinases involved in growth and angiogenic signaling. A significant subset of patients may also be responsive to immune strategies.Areas covered: This review outlines approaches of targeting upregulated growth pathways including Insulin-like Growth Factor, Vascular Endothelial Growth Factor, Fibroblast Growth Factor and Epidermal Growth Factor Receptor in ACC. Data of immune checkpoint blockade with nivolumab, ipilimumab, pembrolizumab and avelumab is explored in detail. Genomic studies indicate that up to 40% of ACC are driven by dysregulated WNT and glucocorticoid signaling, special focus is placed on emerging drugs in these pathways.Expert opinion: Progress in the treatment of ACC has faced challenges stemming from the rarity of the disease. Given recent advances in the understanding of the molecular pathogenesis of ACC, a window of opportunity has now opened to make significant progress in developing therapeutic options that target key pathways such as excessive glucocorticoid signaling, WNT signaling, cell cycle and immune checkpoints.

IL-13Rα2 gene expression is a biomarker of adverse outcome in patients with adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is a rare but aggressive endocrine malignancy that usually results in a fatal outcome. To allow the better clinical management and reduce mortality, we searched for clinical and molecular markers that are reliable predictor of disease severity and clinical outcome in ACC patients. We determined a correlation between the overexpression of IL-13Rα2 and the clinical outcome in ACC patients using comprehensive data available in The Cancer Genome Atlas (TCGA) database. The dataset of 79 ACC subjects were divided into groups of low, medium, or high expression of IL-13Rα2 as determined by RNA-seq. These patients were also stratified by length of survival, overall survival, incidence of a new tumor event, incidence of metastasis, and production of excess hormones. We report a correlation between IL-13Rα2 expression and survival of subjects with ACC. High expression of IL-13Rα2 in ACC tumors was significantly associated with a lower patient survival rate and period of survival compared to low expression (p = 0.0084). In addition, high IL-13Rα2 expression was significantly associated with a higher incidence of new tumor events and excess hormone production compared to low or medium IL-13Rα2 expression. Within the cohort of patients that produced excess hormone, elevated IL-13Rα2 expression was significantly associated with a lower survival rate. Additionally, IL-13Rα1 had a potential relationship between transcript level and ACC survival. Our results and promising antitumor activity in preclinical models and trials indicate that IL-13Rα2 expression is an important prognostic biomarker of ACC disease outcome and a promising target for therapeutic treatment of ACC.

Identification of immune-related biomarkers in adrenocortical carcinoma: Immune-related biomarkers for ACC.

Emerging evidence has suggested that the tumor microenvironment, including immune infiltration, plays a crucially important role in tumor progression. Nevertheless, limited studies have been conducted on this topic in adrenocortical carcinoma. The present study aimed to explore the immune-related biomarkers in adrenocortical carcinoma. CIBERSORT was used to estimate the abundances of 22 kinds of immune cells, and univariable Cox analysis was performed to find survival-related immune cells with both Overall Survival (OS) and Progression-Free Interval (PFI). DESeq2 was applied to find differentially expressed genes between adrenocortical carcinoma and normal control samples; subsequently, weighted correlation network analysis and protein-protein interaction (PPI) network analysis were conducted to identify immune-related hub genes. xCell, TISIDB, and MsigDB were searched to validate the immune associations of hub genes. Eventually, univariable Cox and Kaplan-Meier analysis were used to assess the prognostic implications of the hub gene with the GEO database. Consequently, we identified two hub immune-related genes (ERN1, CEP55), GSEA revealed that both were mainly involved in tumor progression and immune response. ROC analysis indicated that ERN1 can accurately predict the 1-, 3-, and 5-year PFI, and CEP55 had the best performance for the prediction of both OS and PFI compared with other traits. Univariable Cox and Kaplan-Meier analysis showed that both genes have a significant effect on prognosis. Furthermore, both hub genes were validated in GEO datasets. The hub genes can provide better insights into tumor microenvironment and serve as potential biomarkers for immunotherapy in adrenocortical carcinoma.

Indoleamine 2,3-Dioxygenase-1 Expression in Adrenocortical Carcinoma.

BACKGROUND: Indoleamine 2,3-dioxygenase 1 (IDO-1) is overexpressed in many human carcinomas and a successful target for therapy in mouse models. Prognosis of patients with advanced adrenocortical carcinoma (ACC) is poor due to the lack of effective treatments, and new therapies are therefore needed. Herein, we investigate whether IDO-1 is expressed in human ACC tissues. METHODS: 53 tissue samples from patients with ACC, adrenal adenoma (AA), adrenocortical tumors (ACTs), and normal adrenal were identified. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded slides for IDO-1. Samples were scored for cytoplasmic staining as per intensity and the percent of positive cells and for stromal staining by percent of positive cells. Tumor characteristics, PD-L1, PDL-2, and CD-8+ T-lymphocyte expression were also determined. RESULTS: Samples from 32 ACC, 3 ACT, 15 AA, and 3 normal adrenal were analyzed. IDO-1 was expressed in tumor tissue in 22 of 32 ACC samples, compared with 8 of 15 AA sample (P = 0.344). IDO-1 expression was significantly increased in stromal tissue of ACC samples (16 of 33), compared with AA samples (0 of 15) (P = 0.001). IDO-1 expression in ACC and AA samples was associated with PD-L2 expression (P = 0.034). IDO-1 expression in ACC stromal tissue was associated with CD8+ T-lymphocyte infiltration (P = 0.028). CONCLUSIONS: IDO-1 is expressed in a majority of ACC samples. Its expression in tumor tissue is associated with PD-L2 expression, and expression in stroma is associated with CD8+ cell infiltration. IDO-1 inhibition, alone or in combination with PD-1 inhibition, could therefore be an interesting target in treatment of ACC.

Interplay between glucocorticoids and tumor-infiltrating lymphocytes on the prognosis of adrenocortical carcinoma.

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare endocrine malignancy. Tumor-related glucocorticoid excess is present in ~60% of patients and associated with particularly poor prognosis. Results of first clinical trials using immune checkpoint inhibitors were heterogeneous. Here we characterize tumor-infiltrating T lymphocytes (TILs) in ACC in association with glucocorticoids as potential explanation for resistance to immunotherapy. METHODS: We performed immunofluorescence analysis to visualize tumor-infiltrating T cells (CD3+), T helper cells (CD3+CD4+), cytotoxic T cells (CD3+CD8+) and regulatory T cells (Tregs; CD3+CD4+FoxP3+) in 146 ACC tissue specimens (107 primary tumors, 16 local recurrences, 23 metastases). Quantitative data of immune cell infiltration were correlated with clinical data (including glucocorticoid excess). RESULTS: 86.3% of ACC specimens showed tumor infiltrating T cells (7.7 cells/high power field (HPF)), including T helper (74.0%, 6.7 cells/HPF), cytotoxic T cells (84.3%, 5.7 cells/HPF) and Tregs (49.3%, 0.8 cells/HPF). The number of TILs was associated with better overall survival (HR for death: 0.47, 95% CI 0.25 to 0.87), which was true for CD4+- and CD8+ subpopulations as well. In localized, non-metastatic ACC, the favorable impact of TILs on overall and recurrence-free survival was manifested even independently of ENSAT (European Network for the Study of Adrenal Tumors) stage, resection status and Ki67 index. T helper cells were negatively correlated with glucocorticoid excess (Phi=-0.290, p=0.009). Patients with glucocorticoid excess and low TILs had a particularly poor overall survival (27 vs. 121 months in patients with TILs without glucocorticoid excess). CONCLUSION: Glucocorticoid excess is associated with T cell depletion and unfavorable prognosis. To reactivate the immune system in ACC by checkpoint inhibitors, an inhibition of adrenal steroidogenesis might be pivotal and should be tested in prospective studies.

Development of an Adrenocortical Cancer Humanized Mouse Model to Characterize Anti-PD1 Effects on Tumor Microenvironment.

CONTEXT: Although the development of immune checkpoint inhibitors has transformed treatment strategies of several human malignancies, research models to study immunotherapy in adrenocortical carcinoma (ACC) are lacking. OBJECTIVE: To explore the effect of anti-PD1 immunotherapy on the alteration of the immune milieu in ACC in a newly generated preclinical model and correlate with the response of the matched patient. DESIGN, SETTING, AND INTERVENTION: To characterize the CU-ACC2-M2B patient-derived xenograft in a humanized mouse model, evaluate the effect of a PD-1 inhibitor therapy, and compare it with the CU-ACC2 patient with metastatic disease. RESULTS: Characterization of the CU-ACC2-humanized cord blood-BALB/c-Rag2nullIl2rγnullSirpaNOD model confirmed ACC origin and match with the original human tumor. Treatment of the mice with pembrolizumab demonstrated significant tumor growth inhibition (60%) compared with controls, which correlated with increased tumor infiltrating lymphocyte activity, with an increase of human CD8+ T cells (P < 0.05), HLA-DR+ T cells (P < 0.05) as well as Granzyme B+ CD8+ T cells (<0.001). In parallel, treatment of the CU-ACC2 patient, who had progressive disease, demonstrated a partial response with 79% to 100% reduction in the size of target lesions, and no new sites of metastasis. Pretreatment analysis of the patient's metastatic liver lesion demonstrated abundant intratumoral CD8+ T cells by immunohistochemistry. CONCLUSIONS: Our study reports the first humanized ACC patient-derived xenograft mouse model, which may be useful to define mechanisms and biomarkers of response and resistance to immune-based therapies, to ultimately provide more personalized care for patients with ACC.

PD-1 Blockade in Advanced Adrenocortical Carcinoma.

PURPOSE: Adrenocortical carcinomas (ACC) are rare and aggressive malignancies with limited treatment options. This study was undertaken to evaluate the immunogenicity of ACC. PATIENTS AND METHODS: Patients with advanced ACC were enrolled in a phase II study to evaluate the clinical activity of pembrolizumab 200 mg every 3 weeks, without restriction on prior therapy. The primary end point was objective response rate. Efficacy was correlated with tumor programmed death-ligand 1 expression, microsatellite-high and/or mismatch repair deficient (MSI-H/MMR-D) status, and somatic and germline genomic correlates. RESULTS: We enrolled 39 patients with advanced ACC and herein report after a median follow-up of 17.8 months (range, 5.4 months to 34.7 months). The objective response rate to pembrolizumab was 23% (nine patients; 95% CI, 11% to 39%), and the disease control rate was 52% (16 patients; 95% CI, 33% to 69%). The median duration of response was not reached (lower 95% CI, 4.1 months). Two of six patients with MSI-H/MMR-D tumors responded. The other seven patients with objective responses had microsatellite stable tumors. The median progression-free survival was 2.1 months (95% CI, 2.0 months to 10.7 months), and the median overall survival was 24.9 months (95% CI, 4.2 months to not reached). Thirteen percent of patients (n = 5) had treatment-related grade 3 or 4 adverse events. Tumor programmed death-ligand 1 expression and MSI-H/MMR-D status were not associated with objective response. CONCLUSION: MSI-H/MMR-D tumors, for which pembrolizumab is a standard therapy, are more common in ACC than has been recognized. In advanced ACC that is microsatellite stable, pembrolizumab provided clinically meaningful and durable antitumor activity with a manageable safety profile.

Expression of FSCN1 and FOXM1 are associated with poor prognosis of adrenocortical carcinoma patients.

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare malignant endocrine tumour. Due to a high tumour recurrence rate, the post-operative overall survival (OS) and disease-free survival (DFS) of ACCs is limited. Our research aims to identify the role of the epithelial-mesenchymal transition (EMT) related genes FSCN1 and FOXM1 in the tumour microenvironment and assess their prognostic value in ACCs. METHODS: Clinical and specimen data from 130 adrenocortical carcinoma (ACC) patients was acquired from the Cancer Genome Atlas (TCGA) database (n = 79) and a West China Hospital (WCH) cohort (n = 51). In the WCH cohort, archived formalin-fixed paraffin embedded (FFPE) samples were collected for immunohistochemical analysis. The correlation between the EMT genes and the tumour microenvironment status was estimated based on the Tumour Immune Estimation Resource (TIMER) algorithm. Kaplan-Meier analysis, followed by univariate and multivariate regression analyses, were performed to identify the prognostic association of FSCN1 and FOXM1. RESULTS: FSCN1 and FOXM1 were over-expressed in ACC tissue when compared with adrenocortical adenoma and normal adrenal tissue. Over-expression of FSCN1 or FOXM1 was associated with the tumour microenvironment and immune signatures in ACCs. Patients with higher expression of FSCN1 or FOXM1 were more likely to have worse prognoses. The prognostic effects were further verified in both early (stage I/II) and advanced (stage III/IV) ACCs. Furthermore, FSCN1 and FOXM1 appeared as independent prognostic factors in ACC. CONCLUSIONS: These results show that FSCN1 and FOXM1 are independent prognostic factors in ACCs and over-expression of FSCN1 or FOXM1 indicates a worse prognosis.

Phase II clinical trial of pembrolizumab efficacy and safety in advanced adrenocortical carcinoma.

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare malignancy without good treatment options. There are limited data about the use of immunotherapy in ACC. We investigated the efficacy and safety of pembrolizumab in patients with metastatic ACC. METHODS: This is a pre-specified cohort of a single-center, investigator-initiated, phase II clinical trial using pembrolizumab monotherapy in patients with rare malignancies. Patients must have had prior treatment fail in the past 6 months before study enrollment. Patients were enrolled from August 2016 to October 2018. Follow-up data were updated as of March 26, 2019. Patients received 200 mg pembrolizumab intravenously every 3 weeks without concomitant oncologic therapy. The primary endpoint was non-progression rate (NPR) at 27 weeks. Other endpoints included adverse events, tumor responses measured independently by objective radiologic criteria, and select immunological markers. RESULTS: Sixteen patients with ACC (including eight women [50%]) were included in this cohort. Ten patients (63%) had evidence of hormonal overproduction (seven had cortisol-producing ACC). Non-progression rate at 27 weeks was evaluable in 14 patients, one patient was lost to follow-up, and one patient left the study because of an adverse event. Five of 14 patients were alive and progression-free at 27 weeks (non-progression rate at 27 weeks was 36, 95% confidence interval 13-65%). Of the 14 patients evaluable for imaging response by immune-related Response Evaluation Criteria in Solid Tumors, two had a partial response (including one with cortisol-producing ACC), seven had stable disease (including three with cortisol-producing ACC), and five had progressive disease, representing an objective response rate of 14% (95% confidence interval 2-43%). Of those who had stable disease, six had disease stabilization that lasted ≥4 months. Severe treatment-related adverse events (≥grade 3) were seen in 2 of 16 patients (13%) and resulted in one patient discontinuing study participation. All studied tumor specimens (14/14) were negative for programmed cell death ligand-1 expression. Thirteen of 14 tumor specimens (93%) were microsatellite-stable. Eight of 14 patients (57%) had a high tumor-infiltrating lymphocyte score on immunohistochemistry staining. CONCLUSIONS: Single-agent pembrolizumab has modest efficacy as a salvage therapy in ACC regardless of the tumor's hormonal function, microsatellite instability status, or programmed cell death ligand-1 status. Treatment was well tolerated in most study participants, with a low rate of severe adverse events. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02721732 , Registered March 29, 2016.

CD8+ T cells stimulated by exosomes derived from RenCa cells mediate specific immune responses through the FasL/Fas signaling pathway and, combined with GM­CSF and IL­12, enhance the anti­renal cortical adenocarcinoma effect.

A satisfactory cure rate for renal cell carcinoma (RCC) is difficult to achieve through traditional immunotherapy. RCC has a relatively high spontaneous regression rate due to tumor immune escape. However, tumor­derived exosomes (TEXs), which effectively carry tumor­associated antigens (TAAs) and trigger stronger antigen­specific tumor immunity against autologous tumors than against other tumors, have been widely viewed as attractive potential vaccines for tumor treatment, although improvements are needed. Therefore, in our study, we determined whether RenCa cell­derived exosome (RDE)­stimulated CD8+ T cells exert a stronger specific cytotoxic effect on autologous tumor cells than on other types of tumor cells through the Fas ligand (FasL)/Fas signaling pathway, and whether the combination of RDE­stimulated CD8+ T cells with GM­CSF and IL­12 enhances the anticancer effect. The results showed that RDEs were isolated, as expected, and promoted an increased percentage of CD8+/CD4+ T cells. RDE­stimulated CD8+ T cells also more effectively facilitated cytotoxicity against RenCa cells when combined with GM­CSF and IL­12 in vitro. Furthermore, immunization with RDEs restrained the growth of RenCa tumors in mouse models, and facilitated the stimulation of a stronger specific cytotoxic CD8+ T cell response via the FasL/Fas signaling pathway in vitro. However, these results were observed less frequently for other types of tumor cells after treatment with RDEs, suggesting that RDEs depend on their antigen specificity to trigger antitumor immune responses. These findings revealed that RDE­stimulated CD8+ T cells combined with GM­CSF and IL­12 can more effectively exert a stronger cytotoxic effect than RDEs alone and that RDEs can induce immunization more effectively against renal cortical adenocarcinoma than against other types of cancer. Therefore, according to our study, exosomes are promising potential vaccines, and the combination of exosome­stimulated CD8+ T cells with GM­CSF and IL­12 may be a novel strategy for the treatment of RCC.

Management of Adrenocortical Carcinoma.

PURPOSE OF REVIEW: Adrenocortical carcinoma (ACC) is a rare endocrine malignancy typically with poor prognosis. This review aims to summarize the current knowledge regarding the clinical management of ACC. RECENT FINDINGS: Surgery remains the cornerstone for localized ACC management. In more advanced cases, debulking surgery when feasible can help with hormonal control and may allow the initiation of systemic therapy. Over the last few years, our understanding of ACC molecular pathogenesis has expanded with no significant change in treatment options. Platinum-based chemotherapy is the gold standard in metastatic ACC despite suboptimal efficacy. Tyrosine kinase inhibitor use did not result in meaningful benefit in ACC patients. Multiple clinical trials are currently exploring the role of immunotherapy in ACC. Despite the remarkable improvement in our understanding of the molecular signature and pathways in ACC, this knowledge did not yield a major breakthrough in management of advanced ACC. Multi-institutional and international collaborations are needed to identify promising treatments and new therapeutic targets to improve the care of ACC patients.

Pediatric adrenocortical tumors: morphological diagnostic criteria and immunohistochemical expression of matrix metalloproteinase type 2 and human leucocyte-associated antigen (HLA) class II antigens. Results from the Italian Pediatric Rare Tumor (TREP) Study project.

Pediatric adrenocortical tumors are neoplasms that only rarely occur in pediatric patients. Their clinical behavior is often unpredictable, and the histologic criteria of malignancy used in adults are not always useful in children. The aim of this study was to validate the prognostic value of the pathologic criteria of Wieneke et al and to evaluate the potential prognostic expression of matrix metalloproteinase 2 and human leucocyte-associated antigen (HLA) class II antigens in a series of 20 pediatric patients affected by adrenocortical tumors, who were enrolled in the Italian Pediatric Rare Tumor (TREP) Study between 2000 and 2007. The age range was 0 to 17.5 years (mean, 7.28 years) with a male-female ratio of 1:2. The mean follow-up was 64.4 months. The histologic diagnoses were reviewed, and the cases were classified using the criteria for malignancy proposed by Wieneke et al. The immunohistochemical expression of matrix metalloproteinase 2 and HLA class II antigens was scored by semiquantitative analysis and compared with the clinicopathologic parameters and outcome. Based on the scoring system of Wieneke et al, 7 tumors were classified as malignant; 12 tumors, as benign; and only 1 tumor, with "unpredictable behavior." In all cases, the clinical behavior was consistent with the pathologic criteria of Wieneke et al. Notably, areas of regressive myxoid changes, not included among the criteria of Wieneke et al, were observed in all but 1 case of malignant tumors and only in 2 cases of benign tumors. Matrix metalloproteinase 2 was focally to diffusely expressed in all malignant and in most benign tumors. HLA class II antigens immunoreactivity was absent in all benign tumors and restricted to rare isolated cells in most malignant tumors. Our findings confirm that the pathologic scoring system of Wieneke et al is a simple and reproducible diagnostic tool to predict prognosis in pediatric adrenocortical tumors. Unlike in their adult counterpart, the expression of matrix metalloproteinase 2 or the loss of HLA class II antigens does not discriminate between benign and malignant tumors in children. Although pediatric adrenocortical tumors seem to be similar histologically to their adult counterparts, it is likely that they have distinctive molecular features.

Differential immunoprofiles of hepatocellular carcinoma, renal cell carcinoma, and adrenocortical carcinoma: a systemic immunohistochemical survey using tissue array technique.

The differential diagnoses of hepatocellular carcinoma (HCC), renal cell carcinoma (RCC), and adrenocortical carcinoma (ACC) are sometimes difficult due to their overlapping histologic features. Immunohistochemistry is a helpful adjunct in supporting the histologic diagnosis. In this study, the authors used the tissue array technique to systemically analyze the efficacy of different immunohistochemical panels in discerning these neoplasms. Immunohistochemical stains were performed on a total of 895 tumors (including 170 HCCs, 176 RCCs, and 40 ACCs) using monoclonal antibodies against hepatocyte antigen (HPA), CD10, RCC marker, vimentin, alpha-inhibin, keratins (KL-1, CAM 5.2, 7, and 20), epithelial membrane antigen, and polyclonal antibodies against carcinoembryonic antigen (pCEA) and alpha-fetoprotein, and antibodies Melan-A (A103), MOC31, and BG8. HPA immunostain alone detected 85.9% of HCCs, and the addition of canalicular pattern of pCEA and CD10 immunostains raised the sensitivity to 94.7%. RCC marker was positive in 54.5% of RCCs but was negative in all non-RCC tumors. Using positive CD10 and negative HPA and pCEA together with RCC marker increased the sensitivity to 74.4%. Immunoreactivity for alpha-inhibin and A103 could be detected in 67.5% and 55% of ACCs, respectively. When the two antibodies were combined, 82.5% of ACCs were labeled. Proper selection of immunohistochemical stains aid in the differential diagnosis of the three neoplasms. Using the tissue array technique, the authors also showed an effective model for comprehensive antibody testing.

Expression of urotensin II and urotensin II receptor mRNAs in various human tumor cell lines and secretion of urotensin II-like immunoreactivity by SW-13 adrenocortical carcinoma cells.

Urotensin II is the most potent vasoconstrictor peptide identified so far. Expression of urotensin II and urotensin II receptor mRNAs was studied in various human tumor cell lines by reverse transcriptase polymerase chain reaction (PCR) method. Secretion of urotensin II by these tumor cells was studied by radioimmunoassay. The tumor cell lines studied were T98G glioblastoma cells, IMR-32 neuroblastoma cells, NB69 neuroblastoma cells, BeWo choriocarcinoma cells, SW-13 adrenocortical carcinoma cells, DLD-1 colorectal adenocarcinoma cells and HeLa cervical cancer cells. Urotensin II mRNA was expressed in 6 tumor cell lines except for NB69 neuroblastoma cells. Urotensin II receptor mRNA was expressed in all 7 tumor cell lines. A significant amount of urotensin II-like immunoreactivity was detected only in the culture medium of SW-13 adrenocortical carcinoma cells by radioimmunoassay. Sephadex G-50 column chromatography showed that the urotensin II-like immunoreactivity in the culture medium extract was eluted earlier than synthetic human urotensin II, suggesting that SW-13 cells secreted higher molecular weight materials, perhaps partially processed forms of the urotensin II precursor. Reverse phase high-performance liquid chromatography (HPLC) showed three immunoreactive peaks, one of which was eluted in the position of urotensin II. The present study has shown for the first time expression of urotensin II and urotensin II receptor mRNAs in various tumor cell lines and the secretion of urotensin II-like immunoreactivity by SW-13 adrenocortical carcinoma cells.

Immunoreactivity for A103, an antibody to melan-A (Mart-1), in adrenocortical and other steroid tumors.

The Melan-A (MART-1) gene encodes an antigen recognized by cytotoxic T cells. It has been said to be restricted in its expression to melanocytes. However, here we report the presence of immunoreactivity for A103, an antibody to Melan-A, in five adrenocortical adenomas, 16 primary and 13 metastatic adrenocortical carcinomas, four Leydig cell tumors of the testis, and three Sertoli-Leydig cell tumors of the ovary. To evaluate the potential diagnostic role of this antibody, we studied immunoreactivity for A103 in 111 carcinomas, 40 germ cell tumors, and 33 miscellaneous nonmelanocytic epithelioid tumors. All of them were negative for A103. Our findings suggest that once melanoma is excluded, A103 can aid in the recognition of steroid hormone-producing tumors and may be particularly useful in the diagnosis of adrenocortical carcinoma. The presence of immunoreactivity for A103 practically excludes any other carcinoma that may enter into the differential diagnosis of adrenocortical tumors.