Overexpression of CXC chemokines by an adrenocortical carcinoma: a novel clinical syndrome

Validated predictive model for treatment and prognosis of adrenocortical carcinoma

BACKGROUND

Adrenocortical carcinoma has a poor prognosis and multiple clinical, pathological, and treatment variables. Currently, we lack a prognostic and treatment calculator to determine the survival and efficacy of adjuvant chemoradiation. We aimed to validate a calculator to assess prognosis and treatment.

METHODS

We searched the National Cancer Database to identify patients with adrenocortical carcinoma surgically treated from 2004 to 2020 and randomly allocated them into a training (80%) or validation set (20%). We analyzed the variables of age; sex; Charlson Comorbidity Index; insurance status; tumor size; pathologic tumor, node, and metastasis categories; surgical margins; and use of chemotherapy and radiation therapy. We used Cox regression prediction models and bootstrap coefficients to generate a mathematical model to predict 5- and 10-year overall survival. After using the area under the curve analysis to assess the model's performance, we compared overall survival in the training and validation sets.

RESULTS

Multivariable analysis of the 3,480 patients included in the study revealed that all variables were significant except sex (P < .05) and incorporated into a mathematical model. The area under the curve for 5- and 10-year overall survival was 0.68 and 0.70, respectively, for the training set and 0.70 and 0.72, respectively, for the validation set. For the bootstrap coefficients, the 5- and 10-year overall survival was 6.4% and 4.1%, respectively, above the observed mean.

CONCLUSION

Our model predicts the overall survival of patients with adrenocortical carcinoma based on clinical, pathologic, and treatment variables and can assist in individualizing treatment.

Preclinical Models of Adrenocortical Cancer

Adrenocortical cancer is an aggressive endocrine malignancy with an incidence of 0.72 to 1.02 per million people/year, and a very poor prognosis with a five-year survival rate of 22%. As an orphan disease, clinical data are scarce, meaning that drug development and mechanistic research depend especially on preclinical models. While a single human ACC cell line was available for the last three decades, over the last five years, many new in vitro and in vivo preclinical models have been generated. Herein, we review both in vitro (cell lines, spheroids, and organoids) and in vivo (xenograft and genetically engineered mouse) models. Striking leaps have been made in terms of the preclinical models of ACC, and there are now several modern models available publicly and in repositories for research in this area.

Pan-Cancer Analysis of TLE3 Revealed Its Value in Tumor Microenvironment and Prognosis

Background. Transducin-like enhancer of split 3 (TLE3), a member of the TLE gene family, is related to tumor genesis and progression. However, whether TLE3 played a crucial role in the whole pan-cancer remained unknown. Methods. Comprehensive analysis of TCGA, GEO, and GTEx data with an online tool, and R language was performed to explore the relationship of TLE3 expression between prognosis, gene mutation, protein phosphorylation, DNA methylation, tumor microenvironment, and related pathways in 33 tumors. Results. TLE3 was high-expressed in most tumors, and TLE3 expression and the prognosis of some tumor types were significantly correlated. The level of TLE3 expression in 33 cancer types was closely associated with DNA methylation. High-level phosphorylation sites of Tle3, such as S267 and S217, may promote cancers. In terms of the tumor microenvironment, TLE3 affected a wide variety of cancers, especially PRAD and LIHC, and TLE3 may act on them via immune-related pathways. Conclusions. The current work provided the first comprehensive investigation of TLE3 in a pan-cancer study, highlighting the role of TLE3 in the tumor immune microenvironment, and also determined the potential of TLE3 as a prognostic, immunotherapy response, and diagnostic biomarker in many cancers. However, the present results were preliminary and required further validation as this study was based on bioinformatics analyses.

Severe Cholestatic Jaundice (Stauffer Syndrome) as a Rare Paraneoplastic Manifestation in Adrenocortical Carcinoma

Background

Adrenocortical carcinoma (ACC) is a rare malignancy arising from the adrenal cortex. While ACC can be associated with adrenal hormone excess syndromes, classic paraneoplastic syndromes are rarely seen. Stauffer syndrome, a paraneoplastic phenomenon characterized by reversible cholestasis in the absence of liver metastases, has been described with renal carcinoma and other malignancies but has not been previously reported in ACC.

Case Presentation

A 38-year-old man presented with emesis, painless jaundice, pruritus, and weight loss. Laboratory evaluation demonstrated elevated total bilirubin of 8.7 mg/dL (N&lt;1.3). Computed tomography revealed a 20.4-cm left adrenal mass without evidence of liver metastases. The patient's condition deteriorated rapidly with progressive renal failure and worsening hyperbilirubinemia. The patient underwent left adrenalectomy, nephrectomy, ureterolysis, and wedge liver biopsy. Histopathology showed necrotic ACC with tumor invasion into the adrenal capsule, no lymphovascular invasion, uninvolved margins, and Ki-67 of 40%. Kidney parenchyma exhibited diffuse pigment casts. The liver specimen contained diffuse bile deposits and minimal chronic inflammation in the portal tracts. He tested positive for pathogenic variant of folliculin (FLCN) gene consistent with Birt-Hogg-Dubé syndrome. Renal function recovered after surgery, and bilirubin level normalized after several weeks. Based on clinical presentation and absence of other etiologies, reversible cholestatic jaundice was attributed to Stauffer syndrome.

Conclusions

This is the first report of a unique presentation of paraneoplastic-related hyperbilirubinemia in the setting of ACC. While extremely rare, Stauffer syndrome should still be considered in differential diagnosis in patients with ACC with liver dysfunction and jaundice without evidence of liver metastases.

Adrenal Incidentaloma

An adrenal incidentaloma is now established as a common endocrine diagnosis that requires a multidisciplinary approach for effective management. The majority of patients can be reassured and discharged, but a personalized approach based upon image analysis, endocrine workup, and clinical symptoms and signs are required in every case. Adrenocortical carcinoma remains a real concern but is restricted to <2% of all cases. Functional adrenal incidentaloma lesions are commoner (but still probably <10% of total) and the greatest challenge remains the diagnosis and optimum management of autonomous cortisol secretion. Modern-day surgery has improved outcomes and novel radiological and urinary biomarkers will improve early detection and patient stratification in future years to come.

Synthetic high-density lipoprotein nanodisks for targeted withalongolide delivery to adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy and has a 5-year survival rate of <35%. ACC cells require cholesterol for steroid hormone production, and this requirement is met via expression on the cell surface of a high level of SRB1, responsible for the uptake of high-density lipoproteins (HDLs), which carry and transport cholesterol in vivo. Here, we describe how this natural lipid carrier function of SRB1 can be utilized to improve the tumor-targeted delivery of a novel natural product derivative - withalongolide A 4,19,27-triacetate (WGA-TA) - which has shown potent antitumor efficacy, but poor aqueous solubility. Our strategy was to use synthetic HDL (sHDL) nanodisks, which are effective in tumor-targeted delivery due to their smallness, long circulation half-life, documented safety, and ability to bind to SRB1. In this study, we prepared sHDL nanodisks using an optimized phospholipid composition combined with ApoA1 mimetic peptide (22A), which has previously been tested in clinical trials, to load WGA-TA. Following optimization, WGA-TA nanodisks showed drug encapsulation efficiency of 78%, a narrow particle size distribution (9.81±0.41 nm), discoid shape, and sustained drug release in phosphate buffered saline. WGA-TA-sHDL nanodisks exhibited higher cytotoxicity in the ACC cell line H295R half maximal inhibitory concentration ([IC50] 0.26±0.045 μM) than free WGA-TA (IC50 0.492±0.115 μM, P<0.05). Fluorescent dye-loaded sHDL nanodisks efficiently accumulated in H295R adrenal carcinoma xenografts 24 hours following dosing. Moreover, daily intraperitoneal administration of 7 mg/kg WGA-TA-loaded sHDL nanodisks significantly inhibited tumor growth during 21-day administration to H295R xenograft-bearing mice compared to placebo (P<0.01). Collectively, these results suggest that WGA-TA-loaded nanodisks may represent a novel and beneficial therapeutic strategy for the treatment of ACC.

Adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy, often with an unfavorable prognosis. Here we summarize the knowledge about diagnosis, epidemiology, pathophysiology, and therapy of ACC. Over recent years, multidisciplinary clinics have formed and the first international treatment trials have been conducted. This review focuses on evidence gained from recent basic science and clinical research and provides perspectives from the experience of a large multidisciplinary clinic dedicated to the care of patients with ACC.

Neutrophil-mediated tumour angiogenesis: subversion of immune responses to promote tumour growth

Neutrophils are rapidly responding, phagocytes that are an essential part of the host innate immune response to invading micro-organisms. Along with other leucocytes they also play a key role in directing repair at sites of tissue damage. Neutrophils accomplish many of their biological functions by releasing enzymes, anti-microbial agents and cytokines when stimulated to degranulate. There is now increasing evidence to show that tumours are able to recruit neutrophils by secreting a number of tumour cell or stromal-derived chemoattractants. Once within the tumour microenvironment neutrophils, like macrophages, are polarised into a pro-tumour phenotype that can foster tumour growth by secreting factors that directly influence tumour cell proliferation, drive immunosuppression and promote tumour angiogenesis. In this review we discuss the likely mechanisms by which neutrophils are recruited into the tumour and then elaborate on how these cells may induce tumour vascularisation by the secretion of powerful pro-angiogenic factors.

Human adrenocortical carcinoma cell lines

The human adrenal cortex secretes mineralocorticoids, glucocorticoids and adrenal androgens. These steroids are produced from unique cell types located within the three distinct zones of the adrenal cortex. Disruption of adrenal steroid production results in a variety of diseases that can lead to hypertension, metabolic syndrome, infertility and androgen excess. The adrenal cortex is also a common site for the development of adenomas, and rarely the site for the development of carcinomas. The adenomas can lead to diseases associated with adrenal steroid excess, while the carcinomas are particularly aggressive and have a poor prognosis. In vitro cell culture models provide important tools to examine molecular and cellular mechanisms controlling both the normal and pathologic function of the adrenal cortex. Herein, we discuss currently available human adrenocortical carcinoma cell lines and their use as model systems for adrenal studies.

Upregulated JAG1 enhances cell proliferation in adrenocortical carcinoma

PURPOSE

The purpose of this study was to examine the expression and molecular significance of JAG1, a ligand for the Notch developmental signaling pathway, in adrenocortical carcinoma (ACC).

EXPERIMENTAL DESIGN

Human microarray data were analyzed for genes expressing ligands for the Notch pathway and validated with quantitative real-time PCR (QPCR) and immunoblots of RNA and protein, respectively. ACC cells lines were assessed for Notch pathway member expression by immunoblot, QPCR, and immunofluorescence. Notch pathway activity was also determined using a reporter gene (luciferase) activation. Proliferation experiments using a Jag1 knockdown strategy (Jag1KD) and an inhibitor of Notch-dependent transcription (DNMaml) used a coculture system with fluorescence-activated cell-sorting (FACS) analysis. Tumor stage and mitotic rate of human ACC samples were correlated to JAG1 expression.

RESULTS

The Notch ligand JAG1 mRNA and protein are upregulated in ACCs. JAG1 upregulation can be modeled in the Y1 mouse ACC cell line that expresses Jag1, Notch receptors, downstream signaling molecules, and exhibits density-dependent Notch activation. Jag1 enhances cell proliferation through activation of canonical Notch signaling as shown through Jag1KD and coculture experiments. Inhibition of Notch signaling at the level of postreceptor signaling (DNMaml), results in similar inhibition of cell proliferation. Analysis of clinical data indicates that Jag1 expression correlates with both grade and stage of ACCs, supporting a role of JAG1-dependent Notch activation in late-stage ACCs.

CONCLUSIONS

JAG1 is the primary upregulated Notch ligand in ACCs and enhances ACC cell proliferation and tumor aggressiveness in a non-cell-autonomous manner through activation of Notch signaling in adjacent cells.

Comparison of aldosterone production among human adrenocortical cell lines

Several human adrenocortical cell lines have been used as model systems for aldosterone production. However, these cell lines have not been directly compared with each other. Human adrenal cell lines SW13, CAR47, the NCI-H295 and its sub-strains and sub-clones were compared with regard to aldosterone production and aldosterone synthase (CYP11B2) expression. Culture media was collected 48 h after incubation, aldosterone secretion was measured and the data were normalized to the amount of cell protein. RNA was isolated for microarray analysis and quantitative RT-PCR (qPCR). The cell lines with the highest aldosterone production were further tested with regard to angiotensin II (Ang II) stimulation. Neither aldosterone nor CYP11B2 transcript were detected in SW13 or CAR47 cells. The aldosterone production by the NCI-H295, H295A, H295R-S1, H295R-S2, H295R-S3, HAC13, HAC15 and HAC50 were 119, 1, 6, 826, 18, 139, 412, and 1 334 (pmol/mg protein/48 h), respectively. H295A and H295R-S1 expressed less CYP11B2 than the commonly used H295R-S3 cells; while NCI-H295, H295R-S2, HAC13, HAC15 and HAC50 expressed 24-, 14-, 3-, 10-, and 35-fold higher CYP11B2 compared with the H295R-S3 cells. When treated with Ang II, NCI-H295, H295R-S2, HAC13, HAC15 and HAC50 showed significantly higher aldosterone production than the basal level (p<0.05). A comparison of the available human adrenal cell lines indicates that the H295R-S2 and the clonal cell lines, HAC13, HAC15 and HAC50 produced the highest levels of aldosterone and responded well to Ang II.

Preclinical targeting of the type I insulin-like growth factor receptor in adrenocortical carcinoma

CONTEXT

Drug therapy for adrenocortical carcinoma (ACC), a rare and lethal malignancy, is largely empirical and ineffective. New treatments directed at molecular targets critical to the pathophysiology of ACC may prove more efficacious.

OBJECTIVE

The objective of the study was to profile human adrenal tumors and ACC cell lines to assess activated IGF signaling and determine the efficacy of two IGF receptor (IGF-1R) antagonists alone and in combination with mitotane.

EXPERIMENTAL DESIGN

ACC cell lines that display or lack activated IGF signaling are used to assess the effects of two IGF-1R antagonists in cultured cells and ACC xenograft tumors.

RESULTS

Transcriptional profiling data derived from DNA microarray analysis of human adrenal tumors implicate IGF2 as the single highest up-regulated transcript in the vast majority of carcinomas. We show that the majority of ACC cell lines tested display constitutive IGF ligand production and activation of downstream effector pathways. Both IGF-1R antagonists cause significant dose-dependent growth inhibition in ACC cell lines. Furthermore, we observe that mitotane, the first-line adrenolytic drug used in patients with ACC, results in enhanced growth inhibition when used in combination with the IGF-1R antagonists. We next examined the activity of IGF-1R antagonists against ACC xenografts in athymic nude mice. IGF inhibition markedly reduced tumor growth greater than that observed with mitotane treatment, and combination therapy with mitotane significantly enhanced tumor growth suppression.

CONCLUSION

These findings establish a critical role of IGF signaling in ACC pathophysiology and provide rationale for use of targeted IGF-1R antagonists to treat adrenocortical carcinoma in future clinical trials.

ELR+ CXC chemokine expression in benign and malignant colorectal conditions

BACKGROUND

CXCR2 chemokine ligands CXCL1, CXCL5 and CXCL6 were shown to be involved in chemoattraction, inflammatory responses, tumor growth and angiogenesis. Here, we comparatively analyzed their expression profile in resection specimens from patients with colorectal adenoma (CRA) (n = 30) as well as colorectal carcinoma (CRC) (n = 48) and corresponding colorectal liver metastases (CRLM) (n = 16).

METHODS

Chemokine expression was assessed by microdissection, quantitative real-time PCR (Q-RT-PCR), the enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC).

RESULTS

In contrast to CXCL6, we demonstrated CXCL1 and CXCL5 mRNA and protein expression to be significantly up-regulated in CRC and CRLM tissue specimens in relation to their matched tumor neighbor tissues. Moreover, both chemokine ligands were demonstrated to be significantly higher expressed in CRC tissues than in CRA tissues thus indicating a progressive increase in the transition from the premalignant condition to the development of the malignant status. Although a comparative analysis of the CXCL1/CXCL5 protein expression profiles in CRC patients revealed that the absolute expression level of CXCL1 was significantly higher in comparison to CXCL5, mRNA- and protein overexpression of CXCL5 in CRC and CRLM tissues was much more pronounced (80- and 60- fold in CRC tissues, respectively) in comparison to CXCL1 (5- and 3.5- fold in CRC tissues, respectively).

CONCLUSION

Our results demonstrate a significant association between CXCL1 and CXCL5 expression with CRC and CRLM suggesting for both chemokine ligands a potential role in the progression from CRA to CRC and thus, in the initiation of CRC.

GROalpha is highly expressed in adenocarcinoma of the colon and down-regulates fibulin-1

PURPOSE

The growth-related oncogene alpha (GROalpha) is a secreted interleukin-like molecule that interacts with the CXCR2 G-protein-coupled receptor. We found that the mRNA and protein products of GROalpha are more highly expressed in neoplastic than normal colon epithelium, and we studied potential mechanisms by which GROalpha may contribute to tumor initiation or growth.

EXPERIMENTAL DESIGN

Cell lines that constitutively overexpress GROalpha were tested for growth rate, focus formation, and tumor formation in a xenograft model. GROalpha expression was determined by Affymetrix GeneChip (241 microdissected colon samples), real-time PCR (n = 32), and immunohistochemistry. Primary colon cancer samples were also employed to determine copy number changes and loss of heterozygosity related to the GROalpha and fibulin-1 genes.

RESULTS

In cell cultures, GROalpha transfection transformed NIH 3T3 cells, whereas inhibition of GROalpha by inhibitory RNA was associated with apoptosis, decreased growth rate, and marked up-regulation of the matrix protein fibulin-1. Forced expression of GROalpha was associated with decreased expression of fibulin-1. Expression of GROalpha mRNA was higher in primary adenocarcinomas (n = 132), adenomas (n = 32), and metastases (n = 52) than in normal colon epithelium (P < 0.001). These results were confirmed by real-time PCR and by immunohistochemistry. Samples of primary and metastatic colon cancer showed underexpression of fibulin-1 when compared with normal samples. There were no consistent changes in gene copy number of GROalpha or fibulin-1, implying a transcriptional basis for these findings.

CONCLUSION

Elevated expression of GROalpha is frequent in adenocarcinoma of the colon and is associated with down-regulation of the matrix protein fibulin-1 in experimental models and in clinical samples. GROalpha overexpression abrogates contact inhibition in cell culture models, whereas inhibition of GROalpha expression is associated with apoptosis. Importantly, coexpression of fibulin-1 with GROalpha abrogates key aspects of the transformed phenotype, including tumor formation in a murine xenograft model. Targeting GRO proteins may provide new opportunities for treatment of colon cancer.

Interleukin-8 synthesis, regulation, and steroidogenic role in H295R human adrenocortical cells

The adrenal gland secretes several cytokines, and cytokines modulate steroid secretion by this gland. In this study, a survey of cytokine production by H295R human adrenocortical cells demonstrated that these cells secreted IL-2, IL-4, IL-8, IL-10, IL-13, and TNFalpha but not IL-5, IL-12, or interferon-gamma. IL-8 was the IL secreted at higher concentration. IL-8 secretion, its regulation, and role in steroidogenesis were further studied. Secreted ILs and steroids were measured by ELISA in cell culture supernatant. IL-8 mRNA was quantified by real-time RT-PCR. H295R cells and human adrenal gland expressed IL-8 mRNA. Angiotensin II, potassium, endothelin-1, IL-1alpha, IL-1beta, TNFalpha, and Escherichia coli lipopolysaccharide dose-dependently increase IL-8 secretion by H295R cells after 24 h incubation. IL-6 had no effect on IL-8 secretion. Angiotensin II time-dependently increased IL-8 secretion by H295R cells up to 48 h. Angiotensin II caused a biphasic increase in IL-8 mRNA expression with a peak 6 h after stimulation. TNFalpha synergized angiotensin II, potassium, and IL-1alpha-mediated IL-8 secretion. IL-8 did not modify aldosterone or cortisol secretion by H295R cells under basal or stimulated (angiotensin II or potassium) conditions. In conclusion, it is demonstrated for the first time that human adrenal cells expressed and secreted IL-8 under the regulation of angiotensin II, potassium, endothelin-1, and immune peptides. Adrenal-secreted IL-8 is one point of convergence between the adrenal gland and the immune system and may have relevance in physiological and pathophysiological conditions associated with increased levels of aldosterone secretagogues and the immune system.

Gelatinase B/MMP-9 and neutrophil collagenase/MMP-8 process the chemokines human GCP-2/CXCL6, ENA-78/CXCL5 and mouse GCP-2/LIX and modulate their physiological activities

On chemokine stimulation, leucocytes produce and secrete proteolytic enzymes for innate immune defence mechanisms. Some of these proteases modify the biological activity of the chemokines. For instance, neutrophils secrete gelatinase B (matrix metalloproteinase-9, MMP-9) and neutrophil collagenase (MMP-8) after stimulation with interleukin-8/CXCL8 (IL-8). Gelatinase B cleaves and potentiates IL-8, generating a positive feedback. Here, we extend these findings and compare the processing of the CXC chemokines human and mouse granulocyte chemotactic protein-2/CXCL6 (GCP-2) and the closely related human epithelial-cell derived neutrophil activating peptide-78/CXCL5 (ENA-78) with that of human IL-8. Human GCP-2 and ENA-78 are cleaved by gelatinase B at similar rates to IL-8. In addition, GCP-2 is cleaved by neutrophil collagenase, but at a lower rate. The cleavage of GCP-2 is exclusively N-terminal and does not result in any change in biological activity. In contrast, ENA-78 is cleaved by gelatinase B at eight positions at various rates, finally generating inactive fragments. Physiologically, sequential cleavage of ENA-78 may result in early potentiation and later in inactivation of the chemokine. Remarkably, in the mouse, which lacks IL-8 which is replaced by GCP-2/LIX as the most potent neutrophil activating chemokine, N-terminal clipping and twofold potentiation by gelatinase B was also observed. In addition to the similarities in the potentiation of IL-8 in humans and GCP-2 in mice, the conversion of mouse GCP-2/LIX by mouse gelatinase B is the fastest for any combination of chemokines and MMPs so far reported. This rapid conversion was also performed by crude neutrophil granule secretion under physiological conditions, extending the relevance of this proteolytic cleavage to the in vivo situation.

The adrenal hormone metabolism in the immune/inflammatory reaction

The interactions between the immune system and HPA axis may be characterized by a circuit which includes; (i) activation of the HPA axis and initiation of the stress response which, in term, has immunomodulating properties; (ii) a feedback mechanism derived from the immune system which regulates the HPA axis. Over the past few years, it has become evident that the adrenal gland, itself, as the main effector organ of the HPA axis, is a major site for both the synthesis and action of numerous cytokines. In addition to the cytokine mediated activation of adrenal regulation there are cytokine independent cell-cell mediated immune-adrenal interactions. The nature of this immune-endocrine crosstalk is implicated in adrenal dysfunction and disease. During inflammatory and autoimmune disorders including sepsis, inflammatory bowel disease and rheumatoid arthritis, the immune-adrenal crosstalk becomes more critical in maintaining an adequate adrenal stress response.

Signaling pathways in adrenocortical cancer

Adrenocortical carcinoma is a rare tumor that carries a very poor prognosis. Despite efforts to develop new therapeutic regimens to treat this disease, surgery remains the mainstay of treatment. Laboratory studies of adrenocortical cancers have revealed a wide variety of signaling pathways that can be altered in these neoplasms. Although ACTH signaling through adenylyl cyclase and protein kinase A is important for normal adrenal cellular physiology, there is evidence to suggest that this pathway may inhibit the growth of adrenocortical tumors, and that inactivation of the ACTH receptor may promote tumor formation. Although multiple signal transduction pathways are essential for normal adrenal growth and hormone secretion, efforts to identify events required for neoplastic transformation have met with limited success. Alterations that have frequently been observed in adrenocortical carcinoma include up-regulation of the IGF-II system, as well as mutations in TP53 and RAS. Current studies aim to elucidate the mechanisms of tumor growth by studying proproliferative signaling pathways, such as those involving Akt/PKB and the mitogen-activated protein kinases (MAPKs). Although studies of single pathways have been helpful in guiding investigations, new tools to study the integration and multiplicity of signaling pathways hold the hope of improved understanding of the signaling pathway alterations in adrenocortical cancer.