The role of molecular profiling in adrenocortical carcinoma

Adrenocortical carcinoma: a practical guide for clinicians

Adrenocortical carcinoma is a rare endocrine malignancy. The management of patients with adrenocortical carcinoma is challenging for several reasons, including its heterogeneous but frequently aggressive biological behaviour; tumour-related hormonal excess (eg, Cushing's syndrome or virilisation); the overall paucity of evidence regarding diagnostic investigation and treatment; the approval of only one drug (mitotane); and the scarcity of centres with sufficient experience. In this Review, we present 25 questions on the most important aspects of the clinical management of adult patients with adrenocortical carcinoma that we have frequently asked ourselves over the past 25 years. We offer our personal answers and perspectives, drawing upon published evidence as well as more than 60 years of collective clinical experience and insights from our management of more than 1700 patients across two centres in Germany and Italy.

Emerging role of IGF1R and IR expression and localisation in adrenocortical carcinomas

BACKGROUND

The insulin-like growth factor 2 (IGF2) is overexpressed in 90% of adrenocortical carcinomas (ACC) and promotes cell proliferation via IGF1R and isoform A of insulin receptor (IRA). However, IGF2 role in ACC tumourigenesis has not been completely understood yet, and the contribution of IGF1R and IRA in mediating ACC cell growth has been poorly explored. This study aimed to investigate IGF1R and IR expression and localisation, including the expression of IR isoforms, in ACC and adrenocortical adenomas (ACA), and their role in IGF2-driven proliferation.

METHODS

Immunohistochemistry staining of IGF1R and IR was performed on 118 ACC and 22 ACA to evaluate their expression and cellular localisation and statistical analyses were carried out to assess correlations with clinicopathological data. The expression of IRA and IRB in ACC and ACA tissues, ACC cell lines and ACC and ACA primary cultures was determined by RT-qPCR. To appraise the specific role of IGF1R and IR in mediating IGF2 mitogenic pathway, single and double silencing of receptors and their inhibition in 2 ACC cell lines derived from primary tumours (H295R and JIL-2266) and 2 derived from metastatic tumours (MUC-1 and TVBF-7) as well as in ACC and ACA primary cultures were performed.

RESULTS

We found a higher IGF1R plasma membrane localisation in ACC compared to ACA. In ACC this localisation was associated with higher Ki67 and Weiss score. IR was expressed in about half of ACC and in all ACA but, in ACC, it was associated with higher Ki67 and Weiss score. RT-qPCR revealed that the prevalent isoform of IR was IRA in ACC and ACA, but not in normal adrenals. In ACC cell lines, double IGF1R + IR silencing reduced cell proliferation in JIL-2266, MUC-1 and TVBF-7 but not in H295R. In ACC, but not ACA, primary cultures, cell proliferation was reduced after IR but not IGF1R knockdown.

CONCLUSIONS

Overall, these data suggest that IGF1R localisation and IR expression represent new biomarkers predicting tumour aggressiveness, as well as possible molecular markers useful to patients' stratification for more individualized IGF1R-IR targeted therapies or for novel pharmacological approaches specifically targeting IRA isoform.

Necrosis in Preoperative Cross-Sectional Imaging and Postoperative Histology Is a Diagnostic Marker for Malignancy of Adrenocortical Tumors

Necrosis in postoperative histology has been reported as being specific for adrenocortical carcinoma (ACC) compared to adenoma. We therefore retrospectively analyzed the diagnostic accuracy of the finding of necrosis in preoperative cross-sectional imaging and postoperative histology as a marker for ACC in our patient cohort. Among the 411 adrenalectomies in 396 patients performed between 2008 and April 2022, 30 cases of ACC (7.6%) were identified, with one tumor measuring less than 40 mm excluded. All 45 benign adrenocortical tumors of at least 40 mm in diameter, including Cushing, Conn, and hormonally inactive adenomas, served as controls. Preoperative imaging was available for 40 benign and 27 malignant adrenocortical tumors. In total, 10 of 40 (25%) benign adrenocortical tumors and 22 of 27 (81%) ACCs showed signs of possible necrosis in preoperative imaging. Pathologic examination confirmed necrosis in 1 of 40 (2.5%) benign tumors and in 26 out of 27 (96%) malignant tumors. The specificities of possible necrosis in preoperative imaging and necrosis in histology for diagnosing ACC were 75% and 97.5%, respectively, whereas the sensitivities were 81% and 96%, respectively. Signs of possible necrosis in radiologic imaging and tumor necrosis in histology proved to be very good predictive markers for the diagnosis of malignant adrenocortical tumors.

The Role of the IGF2 Methylation Score in Diagnosing Adrenocortical Tumors with Unclear Malignant Potential-Feasibility of Formalin-Fixed Paraffin-Embedded Tissue

The differentiation between benign and malignant adrenocortical tumors based on pathological assessment can be difficult. We present a series of 17 patients with unclear malignant tumors, of whom six had recurrent or metastatic disease. The assessment of the methylation pattern of insulin-like growth factor 2 (IGF2) regulatory regions in fresh frozen material has shown to be valuable in determining the malignancy of adrenocortical tumors, although this has not been elaborately tested in unclear malignant tumors. Since fresh frozen tissue was only available in six of the patients, we determined the feasibility of using formalin-fixed paraffin-embedded (FFPE) tissue for this method. We isolated DNA from FFPE tissue and matched the fresh frozen tissue of three patients with adrenocortical carcinoma. Methylation patterns of IGF2 regulatory regions were determined by pyrosequencing using different amounts of bisulfite-converted DNA (5 ng, 20 ng, 40 ng). Compared to fresh frozen tissue, FFPE tissue had a higher failure rate (fresh frozen 0%; FFPE 18.5%) and poor-to-moderate replicability (fresh frozen rho = 0.89-0.99, median variation 1.6%; FFPE rho = -0.09-0.85, median variation 7.7%). There was only a poor-to-moderate correlation between results from fresh frozen and FFPE tissue (rho = -0.28-0.70, median variation 13.2%). In conclusion, FFPE tissue is not suitable for determining the IGF2 methylation score in patients with an unclear malignant adrenocortical tumor using the currently used method. We, therefore, recommend fresh frozen storage of resection material for diagnostic and biobank purposes.

Comprehensive pan-cancer analysis and the regulatory mechanism of AURKA, a gene associated with prognosis of ferroptosis of adrenal cortical carcinoma in the tumor micro-environment

Background: The only curative option for patients with locally or locally advanced adrenocortical carcinoma is primary tumor curative sexual resection (ACC). However, overall survival remains low, with most deaths occurring within the first 2 years following surgery. The 5-year survival rate after surgery is less than 30%. As a result, more accurate prognosis-related predictive biomarkers must be investigated urgently to detect patients' disease status after surgery. Methods: Data from FerrDb were obtained to identify ferroptosis-related genes, and ACC gene expression profiles were collected from the GEO database to find differentially expressed ACC ferroptosis-related genes using differential expression analysis. The DEFGs were subjected to Gene Ontology gene enrichment analysis and KEGG signaling pathway enrichment analysis. PPI network building and predictive analysis were used to filter core genes. The expression of critical genes in ACC pathological stage and pan-cancer was then investigated. In recent years, immune-related factors, DNA repair genes, and methyltransferase genes have been employed in diagnosing and prognosis of different malignancies. Cancer cells are mutated due to DNA repair genes, and highly expressed DNA repair genes promote cancer. Dysregulation of methyltransferase genes and Immune-related factors, which are shown to be significantly expressed in numerous malignancies, also plays a crucial role in cancer. As a result, we investigated the relationship of AURKA with immunological checkpoints, DNA repair genes, and methyltransferases in pan-cancer. Result: The DEGs found in the GEO database were crossed with ferroptosis-related genes, yielding 42 differentially expressed ferroptosis-related genes. Six of these 42 genes, particularly AURKA, are linked to the prognosis of ACC. AURKA expression was significantly correlated with poor prognosis in patients with multiple cancers, and there was a significant positive correlation with Th2 cells. Furthermore, AURKA expression was positively associated with tumor immune infiltration in Lung adenocarcinoma (LUAD), Liver hepatocellular carcinoma (LIHC), Sarcoma (SARC), Esophageal carcinoma (ESCA), and Stomach adenocarcinoma (STAD), but negatively correlated with the immune score, matrix score, and calculated score in these tumors. Further investigation into the relationship between AURKA expression and immune examination gene expression revealed that AURKA could control the tumor-resistant pattern in most tumors by regulating the expression level of specific immune examination genes. Conclusion: AURKA may be an independent prognostic marker for predicting ACC patient prognosis. AURKA may play an essential role in the tumor microenvironment and tumor immunity, according to a pan-cancer analysis, and it has the potential to be a predictive biomarker for multiple cancers.