Linsitinib (OSI-906) versus placebo for patients with locally advanced or metastatic adrenocortical carcinoma: a double-blind, randomised, phase 3 study

The IGF-II-Insulin Receptor Isoform-A Autocrine Signal in Cancer: Actionable Perspectives

Insulin receptor overexpression is a common event in human cancer. Its overexpression is associated with a relative increase in the expression of its isoform A (IR^A), a shorter variant lacking 11 aa in the extracellular domain, conferring high affinity for the binding of IGF-II along with added intracellular signaling specificity for this ligand. Since IGF-II is secreted by the vast majority of malignant solid cancers, where it establishes autocrine stimuli, the co-expression of IGF-II and IR^A in cancer provides specific advantages such as apoptosis escape, growth, and proliferation to those cancers bearing such a co-expression pattern. However, little is known about the exact role of this autocrine ligand–receptor system in sustaining cancer malignant features such as angiogenesis, invasion, and metastasis. The recent finding that the overexpression of angiogenic receptor kinase EphB4 along with VEGF-A is tightly dependent on the IGF-II/IR^A autocrine system independently of IGFIR provided new perspectives for all malignant IGF2omas (those aggressive solid cancers secreting IGF-II). The present review provides an updated view of the IGF system in cancer, focusing on the biology of the autocrine IGF-II/IR^A ligand–receptor axis and supporting its underscored role as a malignant-switch checkpoint target.

High expression of SMYD3 indicates poor survival outcome and promotes tumour progression through an IGF-1R/AKT/E2F-1 positive feedback loop in bladder cancer

The AKT/mTOR pathway is critical for bladder cancer (BC) pathogenesis and is hyper-activated during BC progression. In the present study, we identified a novel positive feedback loop involving oncogenic factors histone methyltransferase SMYD3, insulin-like growth factor-1 receptor (IGF-1R), AKT, and E2F-1. SMYD3 expression was significantly up-regulated in BC tumors and positively associated with histological grade, lymph node metastasis, and shorter patient survival. Depletion of SMYD3 inhibited BC cell proliferation, colony formation, migration, invasion, and xenograft tumor growth. Mechanistically, SMYD3 inhibition led to the diminished AKT/mTOR signaling activity, thereby triggering deleterious effects on BC cells. Furthermore, SMYD3 directly activates the expression of IGF-1R, a critical activator of AKT in BC, by inducing hyper-methylation of histone H3-K4 and subsequent chromatin remodeling in the IGF-1R promoter region. On the other hand, E2F-1, a downstream factor of the AKT pathway, binds to the E2F-1 binding motifs at the SMYD3 promoter and consequently induces SMYD3 transcription and expression. Thus, SMYD3/IGF-1R/AKT/E2F-1 forms a positive feedback loop leading to the hyper-activated AKT signaling. Our findings provide not only profound insights into SMYD3-mediated oncogenic activity but also present a unique avenue for treating BC by directly disrupting this signaling circuit.

Targeted Gene Expression Profile Reveals CDK4 as Therapeutic Target for Selected Patients With Adrenocortical Carcinoma

Adrenocortical carcinomas (ACC) are aggressive tumors with a heterogeneous prognosis and limited therapeutic options for advanced stages. This study aims to identify novel drug targets for a personalized treatment in ACC. RNA was isolated from 40 formalin-fixed paraffin-embedded ACC samples. We evaluated gene expression of 84 known cancer drug targets by reverse transcriptase quantitative real time-PCR and calculated fold change using 5 normal adrenal glands as reference (overexpression by fold change >2.0). The most promising candidate cyclin-dependent kinase 4 (CDK4) was investigated at protein level in 104 ACC samples and tested by in vitro experiments in two ACC cell lines (NCI-H295R and MUC1). The most frequently overexpressed genes were TOP2A (100% of cases, median fold change = 16.5), IGF2 (95%, fold change = 52.9), CDK1 (80%, fold change = 6.7), CDK4 (62%, fold change = 2.6), PLK4 (60%, fold change = 2.8), and PLK1 (52%, fold change = 2.3). CDK4 was chosen for functional validation, as it is actionable by approved CDK4/6-inhibitors (e.g., palbociclib). Nuclear immunostaining of CDK4 significantly correlated with mRNA expression (R = 0.52, P < 0.005). We exposed both NCI-H295R and MUC1 cell lines to palbociclib and found a concentration- and time-dependent reduction of cell viability, which was more pronounced in the NCI-H295R cells in line with higher CDK4 expression. Furthermore, we tested palbociclib in combination with insulin-like growth factor 1/insulin receptor inhibitor linsitinib showing an additive effect. In conclusion, we demonstrate that RNA profiling is useful to discover potential drug targets and that CDK4/6 inhibitors are promising candidates for treatment of selected patients with ACC.

Disease-free interval and tumor functional status can be used to select patients for resection/ablation of liver metastases from adrenocortical carcinoma: insights from a multi-institutional study

BACKGROUND

Adrenocortical carcinoma (ACC) is an aggressive malignancy that frequently metastasizes to the liver. Given the limitations of systemic therapy in this setting, we sought to determine characteristics associated with a two-fold increase in survival with resection/ablation compared to that reported with chemotherapy alone (∼12 months).

METHODS

Patients who underwent resection/ablation at our institutions for ACC liver metastases were identified. Those who survived 12-24 months after metastasectomy were excluded, as the aim was to characterize patients who most clearly benefited from these procedures. Clinicopathologic and treatment characteristics were assessed for associations with survival.

RESULTS

Sixty-two patients met inclusion criteria, of whom 44 survived >24 months and 18 survived <12 months. Patients with extended survival were less likely to have functioning tumors (p = 0.047), had fewer liver metastases (p = 0.047), and a longer disease-free interval (DFI) (median 17.6 vs 2.3 months, p < 0.0001). On multivariable analysis, DFI (OR = 1.33, 95% CI = 1.12-1.58) and non-functioning tumor (OR = 0.13, 95% CI = 0.13-0.56) were independently associated with prolonged survival.

CONCLUSION

Metastasectomy/ablation should be considered for patients with ACC liver metastases. DFI and tumor functional status may be useful in selecting optimal candidates for these procedures.

Insulin-like growth factor 1 modulates the phosphorylation, expression, and activity of organic anion transporter 3 through protein kinase A signaling pathway

Organic anion transporter 3 (OAT3) plays a vital role in removing a broad variety of anionic drugs from kidney, thus avoiding their possible toxicity in the body. In the current study, we investigated the role of insulin-like growth factor 1 (IGF-1) in the regulation of OAT3. We showed that IGF-1 induced a dose- and time-dependent increase in OAT3 transport activity, which correlated well with an increase in OAT3 expression. The IGF-1-induced increase in OAT3 expression was blocked by protein kinase A (PKA) inhibitor H89. Moreover, IGF-1 induced an increase in OAT3 phosphorylation, which was also blocked by H89. These data suggest that the IGF-1 modulation of OAT3 occurred through PKA signaling pathway. To further confirm the involvement of PKA, we treated OAT3-expressing cells with PKA activator Bt2-cAMP, followed by examining OAT activity and phosphorylation. We showed that OAT3 activity and phosphorylation were much enhanced in Bt2-cAMP-treated cells as compared to that in control cells. Finally, linsitinib, an anticancer drug that blocks the IGF-1 receptor, abrogated IGF-1-stimulated OAT3 transport activity. In conclusion, our study demonstrated that IGF-1 regulates OAT3 expression and transport activity through PKA signaling pathway, possibly by phosphorylating the transporter.

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.

Nivolumab in Metastatic Adrenocortical Carcinoma: Results of a Phase 2 Trial

CONTEXT

Systemic treatment of metastatic adrenocortical carcinoma (ACC) remains limited to chemotherapy and mitotane. Preliminary evidence suggesting that antitumor immune responses can be elicited in ACC has fostered interest in checkpoint inhibitors such as anti-PD-1 nivolumab.

OBJECTIVE

The primary endpoint was objective response rate according to the response evaluation criteria in solid tumors. Secondary endpoints were progression-free survival (PFS), overall survival, and safety.

DESIGN

Single-arm, multicenter, phase 2 clinical trial with two-stage design.

SETTING

Comprehensive cancer center.

PATIENTS

Ten adult patients with metastatic ACC previously treated with platinum-based chemotherapy and/or mitotane as well as patients who declined front-line chemotherapy.

INTERVENTION

Nivolumab (240 mg) IV every 2 weeks.

RESULTS

Ten patients with metastatic ACC were enrolled between March and December 2016. The median number of doses of nivolumab administered was two. Three patients only received one treatment [one died of disease progression, one discontinued due to adverse events (AEs), one withdrew after beginning treatment]. The median PFS was 1.8 months. The median follow-up was 4.5 months (range, 0.1 to 25.6 months). Two patients had stable disease for a duration of 48 and 11 weeks, respectively. One patient had an unconfirmed partial response but discontinued the study due to an AE. Most AEs were grade 1/2. The most common grade 3/4 treatment-related AEs were aspartate aminotransferase and alanine aminotransferase elevations, mucositis, and odynophagia.

CONCLUSION

Nivolumab demonstrated modest antitumor activity in patients with advanced ACC. The nivolumab safety profile was consistent with previous clinical experience without any unexpected AEs in this population.

Investigational IGF1R inhibitors in early stage clinical trials for cancer therapy

Introduction: The insulin-like growth factors (IGFs) are a family of secreted peptide hormones with important roles in different cellular and organism functions. The biological activities of the IGFs are mediated by the IGF1 receptor (IGF1R), a cell surface, tyrosine kinase-containing heterotetramer that is linked to numerous cytoplasmic signaling cascades. The IGF1R displays potent antiapoptotic, pro-survival capacities and plays a key role in malignant transformation. Research has identified the IGF1R as a candidate therapeutic target in cancer.Areas covered: We offer a synopsis of ongoing efforts to target the IGF axis for therapeutic purposes. Our review includes a digest of early experimental work that led to the identification of IGF1R as a candidate therapeutic target in oncology.Expert opinion: Targeting of the IGF axis has yielded disappointing results in phase III trials, but it is important to learn from this to improve future trials in a rational manner. The potential of anti-IGF1R antibodies and small molecular weight inhibitors, alone or in combination with chemotherapy or other biological agents, should be investigated further in randomized studies. Moreover, the implementation of predictive biomarkers for patient selection will improve the outcome of future trials. Emerging personalized medicine could have a major impact on IGF1R targeting.

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.

IGF-1R pathway activation as putative biomarker for linsitinib therapy to revert tamoxifen resistance in ER-positive breast cancer

Preclinical studies indicate that activated IGF-1R can drive endocrine resistance in ER-positive (ER+) breast cancer, but its clinical relevance is unknown. We studied the effect of IGF-1R signaling on tamoxifen benefit in patients and we searched for approaches to overcome IGF-1R-mediated tamoxifen failure in cell lines. Primary tumor blocks from postmenopausal ER+ breast cancer patients randomized between adjuvant tamoxifen versus nil were recollected. Immunohistochemistry for IGF-1R, p-IGF-1R/InsR, p-ERα(Ser118), p-ERα(Ser167) and PI3K/MAPK pathway proteins was performed. Multivariate Cox models were employed to assess tamoxifen efficacy. The association between p-IGF-1R/InsR and PI3K/MAPK pathway activation in MCF-7 and T47D cells was analyzed with Western blots. Cell proliferation experiments were performed under various growth-stimulating and -inhibiting conditions. Patients with ER+, IGF-1R-positive breast cancer without p-IGF-1R/InsR staining (n = 242) had tamoxifen benefit (HR 0.41, p = 0.0038), while the results for p-IGF-1R/InsR-positive patients (n = 125) were not significant (HR 0.95, p = 0.3). High p-ERα(Ser118) or p-ERα(Ser167) expression was associated with less tamoxifen benefit. In MCF-7 cells, IGF-1R stimulation increased phosphorylation of PI3K/MAPK proteins and ERα(Ser167) regardless of IGF-1R overexpression. This could be abrogated by the dual IGF-1R/InsR inhibitor linsitinib, but not by the IGF-IR-selective antibody 1H7. In MCF-7 and T47D cells, stimulation of the IGF-1R/InsR pathway resulted in cell proliferation regardless of tamoxifen. Abrogation of cell growth was regained by addition of linsitinib. In conclusion, p-IGF-1R/InsR positivity in ER+ breast cancer is associated with reduced benefit from adjuvant tamoxifen in postmenopausal patients. In cell lines, stimulation rather than overexpression of IGF-1R is driving tamoxifen resistance to be abrogated by linsitinib.

Targeting PDZ-binding kinase is anti-tumorigenic in novel preclinical models of ACC

Adrenocortical carcinoma (ACC) is an aggressive orphan malignancy with less than 35% 5-year survival and 75% recurrence. Surgery remains the primary therapy and mitotane, an adrenolytic, is the only FDA-approved drug with wide-range toxicities and poor tolerability. There are no targeted agents available to date. For the last three decades, H295R cell line and its xenograft were the only available preclinical models. We recently developed two new ACC patient-derived xenograft mouse models and corresponding cell lines (CU-ACC1 and CU-ACC2) to advance research in the field. Here, we have utilized these novel models along with H295R cells to establish the mitotic PDZ-binding kinase (PBK) as a promising therapeutic target. PBK is overexpressed in ACC samples and correlates with poor survival. We show that PBK is regulated by FOXM1 and targeting PBK via shRNA decreased cell proliferation, clonogenicity and anchorage-independent growth in ACC cell lines. PBK silencing inhibited pAkt, pp38MAPK and pHistone H3 altering the cell cycle. Therapeutically, targeting PBK with the small-molecule inhibitor HITOPK032 phenocopied PBK-specific modulation of pAkt and pHistone H3, but also induced apoptosis via activation of JNK. Consistent with in vitro findings, treatment of CU-ACC1 PDXs with HITOPK032 significantly reduced tumor growth by 5-fold (P < 0.01). Treated tumor tissues demonstrated increased rates of apoptosis and JNK activation, with decreased pAkt and Histone H3 phosphorylation, consistent with effects observed in ACC cell lines. Together these studies elucidate the mechanism of PBK in ACC tumorigenesis and establish the potential therapeutic potential of HITOPK032 in ACC patients.

Treatment of Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare malignancy with a poor prognosis. ACC is capable of secreting excess adrenocortical hormones, which can compound morbidity and compromise clinical outcomes. By the time most ACCs are diagnosed, there is usually locoregional or metastatic disease. Surgery is the most important treatment to offer possibility of cure or prolong survival. Several adjuvant therapies are used depending on grade and stage of the tumor and other patient-related factors. This review provides an overview of treatment approaches for ACC, highlighting evidence to support each treatment and acknowledging where more data and research are needed to improve care.

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.

Prognostic Relevance of Steroid Sulfation in Adrenocortical Carcinoma Revealed by Molecular Phenotyping Using High-Resolution Mass Spectrometry Imaging

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare tumor with variable prognosis even within the same tumor stage. Cancer-related sex hormones and their sulfated metabolites in body fluids can be used as tumor markers. The role of steroid sulfation in ACC has not yet been studied. MALDI mass spectrometry imaging (MALDI-MSI) is a novel tool for tissue-based chemical phenotyping.

METHODS

We performed phenotyping of formalin-fixed, paraffin-embedded tissue samples from 72 ACC by MALDI-MSI at a metabolomics level.

RESULTS

Tumoral steroid hormone metabolites-estradiol sulfate [hazard ratio (HR) 0.26; 95% CI, 0.10-0.69; P = 0.005] and estrone 3-sulfate (HR 0.22; 95% CI, 0.07-0.63; P = 0.003)-were significantly associated with prognosis in Kaplan-Meier analyses and after multivariable adjustment for age, tumor stage, and sex (HR 0.29; 95% CI, 0.11-0.79; P = 0.015 and HR 0.30; 95% CI, 0.10-0.91; P = 0.033, respectively). Expression of sulfotransferase SULT2A1 was associated with prognosis to a similar extent and was validated to be a prognostic factor in two published data sets. We discovered the presence of estradiol-17β 3,17-disulfate (E2S2) in a subset of tumors with particularly poor overall survival. Electron microscopy revealed novel membrane-delimited organelles in only these tumors. By applying cluster analyses of metabolomic data, 3 sulfation-related phenotypes exhibited specific metabolic features unrelated to steroid metabolism.

CONCLUSIONS

MALDI-MSI provides novel insights into the pathophysiology of ACC. Steroid hormone sulfation may be used for prognostication and treatment stratification. Sulfation-related metabolic reprogramming may be of relevance also in conditions beyond the rare ACC and can be directly investigated by the use of MALDI-MSI.

Adrenocortical carcinoma - towards genomics guided clinical care

Adrenocortical carcinoma (ACC) is an aggressive and rare neoplasm that originates in the cortex of the adrenal gland. The disease is associated with heterogeneous but mostly poor outcomes and lacks effective pharmaceutical treatment options. Multi-omics studies have defined the landscape of molecular alterations in ACC. Specific molecular signatures can be detected in body fluids, potentially enabling improved diagnostic applications for patients with adrenal tumours. Importantly, pan-molecular data sets further reveal a spectrum within ACC, with three major subgroups that have different disease outcomes. These new subgroups have value as prognostic biomarkers. Research has revealed that the p53-RB and the WNT-β-catenin pathways are common disease drivers in ACC. However, these pathways remain difficult to target by therapeutic interventions. Instead, a unique characteristic of ACC is steroidogenic differentiation, which has emerged as a potential treatment target, with several agents undergoing preclinical or clinical investigations. Finally, a large proportion of ACC tumours have genetic profiles that are associated with promising therapeutic responsiveness in other cancers. All these opportunities now await translation from the laboratory into the clinical setting, thereby offering a real potential of improved survival outcomes and increased quality of life for patients with this serious condition.

The role of mTOR pathway as target for treatment in adrenocortical cancer

Adrenocortical carcinomas (ACCs) are rare tumors with scant treatment options for which new treatments are required. The mTOR pathway mediates the intracellular signals of several growth factors, including the insulin-like growth factors (IGFs), and therefore represents a potential attractive pathway for the treatment of several malignancies including ACCs. Several mTOR inhibitors, including sirolimus, temsirolimus and everolimus, have been clinically developed. This review summarizes the results of the studies evaluating the expression of the mTOR pathway components in ACCs, the effects of the mTOR inhibitors alone or in combination with other drugs in preclinical models of ACCs and the early experience with the use of these compounds in the clinical setting. The mTOR pathway seems a potential target for treatment of patients with ACC, but further investigation is still required to define the potential role of mTOR inhibitors alone or in combination with other drugs in the treatment of ACC patients.

Contemporary preclinical human models of adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is an uncommon and heterogeneous disease and may present differently in children and adults. Management of ACC is dependent on disease stage and complete surgical resection is the only potentially curative treatment. The first and most extensively used adrenocortical cancer cell line, as model system to examine mechanisms controlling normal and pathologic function of adrenal cortex, was initially isolated in 1980. Although NCI-H295 maintained steroid capabilities and adrenocortical characteristics, the lack of new cell lines and animal models of ACC has hampered the progress and development of new therapies. In this review we provide description of cellular and patient-derived tumor xenograft (PDTX) models of ACC generated for the elucidation of the underlying pathogenic mechanisms and preclinical functional studies for this aggressive disease.

Metastatic Adrenocortical Carcinoma: a Single Institutional Experience

Adrenocortical carcinoma (ACC) is a rare malignancy with limited data to guide the management of metastatic disease. The optimal treatment strategies and outcomes of patients with metastatic ACC remain areas of active interest. We retrospectively reviewed patients with ACC who were treated with systemic therapy between January 1997 and October 2016 at The Ohio State University Comprehensive Cancer Center. Kaplan-Meier and Cox proportional hazards regression models were used for survival analysis. We identified 65 patients diagnosed with ACC during the given time period, and 36 patients received systemic therapy for distant metastatic disease. Median age at diagnosis was 50 (range 28-87). Median overall survival (OS) from time of diagnosis of ACC was 27 months (95% CI 19.6-39.3), and median OS from time of systemic treatment for metastatic disease was 18.7 months (95% CI 9.3-26.0). Clinical characteristics at time of initiation of systemic therapy were assessed, and presence of bone metastases (p = 0.66), ascites (p = 0.19), lung metastases (p = 0.12), liver metastases (p = 0.47), as well as hormonal activity of tumor (p = 0.19), were not prognostic for survival. Six patients with liver metastases treated with systemic therapy who received liver-directed therapy with either transarterial chemoembolization (TACE) or selective internal radiation therapy (SIRT) had longer survival than those who did not (p = 0.011). Our data expands the knowledge of clinical characteristics and outcomes of patients with ACC and suggests a possible role for incorporating liver-directed therapies for patients with hepatic metastases.

Therapeutic Targeting of the IGF Axis

The insulin like growth factor (IGF) axis plays a fundamental role in normal growth and development, and when deregulated makes an important contribution to disease. Here, we review the functions mediated by ligand-induced IGF axis activation, and discuss the evidence for the involvement of IGF signaling in the pathogenesis of cancer, endocrine disorders including acromegaly, diabetes and thyroid eye disease, skin diseases such as acne and psoriasis, and the frailty that accompanies aging. We discuss the use of IGF axis inhibitors, focusing on the different approaches that have been taken to develop effective and tolerable ways to block this important signaling pathway. We outline the advantages and disadvantages of each approach, and discuss progress in evaluating these agents, including factors that contributed to the failure of many of these novel therapeutics in early phase cancer trials. Finally, we summarize grounds for cautious optimism for ongoing and future studies of IGF blockade in cancer and non-malignant disorders including thyroid eye disease and aging.

New strategies for applying targeted therapies to adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare, aggressive, and frequently deadly cancer. Up to 75% of all patients will eventually develop metastatic disease, and our current medical therapies for ACC provide limited - if any - survival benefit. These statistics highlight a crucial need for novel approaches. Recent studies performing comprehensive molecular profiling on ACC have illuminated that ACC is comprised of three clinically distinct molecular subtypes, bearing differential regulation of cell cycle, epigenetics, Wnt/β-catenin signaling, PKA signaling, steroidogenesis and immune cell biology. Furthermore, these studies have spurred the development of molecular subtype-based biomarkers, contextualized outcomes of recent clinical trials, and advanced our understanding of the underlying biology of adrenocortical homeostasis and cancer. In this review, we describe these findings and their implications for new strategies to apply targeted therapies to ACC.

Insulin/IGF signaling and discoidin domain receptors: An emerging functional connection

The insulin/insulin-like growth factor system (IIGFs) plays a fundamental role in the regulation of prenatal and postnatal growth, metabolism and homeostasis. As a consequence, dysregulation of this axis is associated with growth disturbance, type 2 diabetes, chronic inflammation and tumor progression. A functional crosstalk between IIGFs and discoidin domain receptors (DDRs) has been recently discovered. DDRs are non-integrin collagen receptors that canonically undergo slow and long-lasting autophosphorylation after binding to fibrillar collagen. While both DDR1 and DDR2 functionally interact with IIGFs, the crosstalk with DDR1 is so far better characterized. Notably, the IIGFs-DDR1 crosstalk presents a feed-forward mechanism, which does not require collagen binding, thus identifying novel non-canonical action of DDR1. Further studies are needed to fully explore the role of this IIGFs-DDRs functional loop as potential target in the treatment of inflammatory and neoplastic disorders.

Identification of candidates for driver oncogenes in scirrhous-type gastric cancer cell lines

Scirrhous‐type gastric cancer (SGC) is one of the most intractable cancer subtypes in humans, and its therapeutic targets have been rarely identified to date. Exploration of somatic mutations in the SGC genome with the next‐generation sequencers has been hampered by markedly increased fibrous tissues. Thus, SGC cell lines may be useful resources for searching for novel oncogenes. Here we have conducted whole exome sequencing and RNA sequencing on 2 SGC cell lines, OCUM‐8 and OCUM‐9. Interestingly, most of the mutations thus identified have not been reported. In OCUM‐8 cells, a novel CD44‐IGF1R fusion gene is discovered, the protein product of which ligates the amino‐terminus of CD44 to the transmembrane and tyrosine‐kinase domains of IGF1R. Furthermore, both CD44 and IGF1R are markedly amplified in the OCUM‐8 genome and abundantly expressed. CD44‐IGF1R has a transforming ability, and the suppression of its kinase activity leads to rapid cell death of OCUM‐8. To the best of our knowledge, this is the first report describing the transforming activity of IGF1R fusion genes. However, OCUM‐9 seems to possess multiple oncogenic events in its genome. In particular, a novel BORCS5‐ETV6 fusion gene is identified in the OCUM‐9 genome. BORCS5‐ETV6 possesses oncogenic activity, and suppression of its message partially inhibits cell growth. Prevalence of these novel fusion genes among SGC awaits further investigation, but we validate the significance of cell lines as appropriate reagents for detailed genomic analyses of SGC.

A phase II study of the orally administered negative enantiomer of gossypol (AT-101), a BH3 mimetic, in patients with advanced adrenal cortical carcinoma

Background Adrenal cortical carcinoma (ACC) is a rare cancer with treatment options of limited efficacy, and poor prognosis if metastatic. AT-101 is a more potent inhibitor of B cell lymphoma 2 family apoptosis-related proteins than its racemic form, gossypol, which showed preliminary clinical activity in ACC. We thus evaluated the efficacy of AT-101 in patients with advanced ACC. Methods Patients with histologically confirmed metastatic, recurrent, or primarily unresectable ACC were treated with AT-101 (20 mg/day orally, 21 days out of 28-day cycles) until disease progression and/or prohibitive toxicity. The primary endpoint was objective response rate, wherein a Response Evaluation Criteria In Solid Tumors (RECIST) partial response rate of 25% would be considered promising and 10% not, with a Type I error of 10% and 90% power. In a 2-stage design, 2 responses were required of the first 21 assessable subjects to warrant complete accrual of 44 patients. Secondary endpoints included safety, progression-free survival and overall survival. Results This study accrued 29 patients between 2009 and 2011; median number of cycles was 2. Seven percent experienced grade 4 toxicity including cardiac troponin elevations and hypokalemia. None of the first 21 patients attained RECIST partial response; accordingly, study therapy was deemed ineffective and the trial was permanently closed. Conclusions AT-101 had no meaningful clinical activity in this study in patients with advanced ACC, but demonstrated feasibility of prospective therapeutic clinical trials in this rare cancer.

IGF and mTOR pathway expression and in vitro effects of linsitinib and mTOR inhibitors in adrenocortical cancer

PURPOSE

The IGF and mTOR-pathways are considered as potential targets for therapy in patients with adrenocortical carcinoma (ACC). This study aims to describe the IGF pathway in ACC and to explore the response to the combined treatment with the IGF1R/IR inhibitor linsitinib, and mTOR inhibitors (sirolimus and everolimus) in in vitro models of ACC.

METHODS

The protein expression level of IGF2, IGF1R and IGF2R was evaluated by immunohistochemistry in 17 human ACCs and the mRNA expression level of IGF1, IGF2, IGF1R, IR isoforms A and B, IGF2R, IGF-Binding-Proteins[IGFBP]-1, 2, 3 and 6 was evaluated by RT-qPCR in 12 samples. In H295R and HAC15 ACC cell lines the combined effects of linsitinib and sirolimus or everolimus on cell survival were evaluated.

RESULTS

A high protein expression of IGF2, IGF1R and IGF2R was observed in 82, 65 and 100% of samples, respectively. A high relative expression of IGF2 mRNA was found in the majority of samples. The mRNA levels of the IRA were higher than that of IRB and IGF1R in the majority of samples (75%). Linsitinib inhibits cell growth in the H295R and HAC15 cell lines and, combined with sirolimus or everolimus, linsitinib showed a significant additive effect.

CONCLUSIONS

In addition to IGF2 and IGF1R, ACC express IGF2R, IRA and several IGFBPs, suggesting that the interplay between the different components of the IGF pathway in ACC could be more complex than previously considered. The addition of mTOR inhibitors to linsitinib may have stronger antiproliferative effects than linsitinib alone.

Adjuvant mitotane therapy is beneficial in non-metastatic adrenocortical carcinoma at high risk of recurrence

Objective Many patients with adrenocortical carcinoma (ACC) suffer from tumor recurrence despite radical surgery. Evidence on the post-operative use of mitotane is controversial and no predictors of response are available. We aimed to assess whether adjuvant mitotane treatment may prolong survival in patients with non-metastatic ACC following complete resection and whether ACC patients at high risk of recurrence may benefit from treatment. Design and methods We retrospectively reviewed data from 152 non-metastatic ACC patients followed at the San Luigi Gonzaga Hospital: 100 patients were treated with adjuvant mitotane and 52 patients were left untreated following surgery. We assessed a number of potential predictive factors of recurrence and death. Mitotane effect was explored stratifying patients by staging (stage I-II vs stage III), hormone secretion (yes vs no) and Ki67 index. Results The non-treated group had a higher risk of recurrence (HR: 2.79, 95%CI: 1.58-4.91; P < 0.001) than mitotane-treated group, while overall survival was not significantly different between groups. Hormone secretion, elevated Weiss score and elevated Ki67 index confer a higher risk of both recurrence and death and stage III ACC of death. Adjuvant mitotane treatment reduced significantly the risk of death in patients with elevated Ki67 index (P = 0.005) and in patients with stage III ACC (P = 0.02). Conclusions Adjuvant mitotane may prolong recurrence-free survival in radically resected ACC patients with acceptable toxicity and may also prolong overall survival in a subgroup of ACC patients at high risk of recurrence.

Metastatic Adrenal Cortical Carcinoma Responding to Octreotide: A Case Report

Advanced adrenocortical carcinoma (ACC) is an aggressive disease with poor prognosis, and the current therapeutic options, such as mitotane or platinum-based chemotherapy regimens, often offer limited efficacy. Here, we present the first report, to the author's knowledge, of metastatic ACC with positive octreoscan scintigraphy that was successfully treated with octreotide long-acting release (LAR). A patient with metastatic ACC who showed poor tolerance to mitotane received octreotide LAR because of positive octreoscan scintigraphy. She obtained major partial response to the somatostatin analog. Interestingly, the expression of somatostatin receptor 2 from the previous local recurrence lesion was negative. The next-generation sequencing-based circulating tumor DNA analysis in the patient was performed and failed to identify any alterations. These findings suggest that octreotide LAR may be a good option for the treatment of metastatic ACC in selected patients.

Insulin-Like Growth Factor and SLC12A7 Dysregulation: A Novel Signaling Hallmark of Non-Functional Adrenocortical Carcinoma

BACKGROUND

Insulin-like growth factor (IGF) dysregulation and gene copy number variations (CNV) are hallmarks of adrenocortical carcinoma (ACC). The contribution of IGF CNVs in adrenal carcinogenesis has not been studied previously. In addition, studies demonstrating an association between SLC12A7 gene amplifications and enhanced metastatic behavior in ACC, as well as reported IGF-SLC12A7 signaling interactions in other cancers, suggest a potential IGF-SLC12A7 signaling circuitry in ACC. Here we investigate the potential complicity of IGF-SLC12A7 signaling in ACC.

STUDY DESIGN

Insulin-like growth factor CNVs were determined by whole-exome sequencing analysis in an exploratory cohort of ACC. Quantitative polymerase chain reaction methods determined IGF1 and IGF2 expression levels and were evaluated for correlation with SLC12A7 expression and tumor characteristics. Insulin-like growth factor CNVs and expression patterns were compared with The Cancer Genome Atlas. In vitro studies determined the relationship of IGF and SLC12A7 co-expression in 2 ACC cell lines, SW-13 and NCI-H295R. Immunohistochemistry assessed IGF1 receptor (IGF1R) activation.

RESULTS

The IGF1 gene was amplified in 9 of 19 ACC samples, similar to findings in The Cancer Genome Atlas database. The IGF1 overexpression was observed in 5 samples and was associated with SLC12A7 overexpression and non-functional, early-stage tumors (p < 0.05). In contrast, IGF2 overexpression was associated with larger tumors (p < 0.05). In vitro IGF treatment of ACC cell lines did not stimulate SLC12A7 expression, and endogenous overexpression and silencing of SLC12A7 significantly altered IGF1 and IGF1R expression without impacting other IGFs. The IGF1R activation was associated with IGF1 overexpression in ACC tumor samples.

CONCLUSIONS

These findings indicate that IGF1 overexpression, caused in part by gene amplifications, is correlated with SLC12A7 overexpression in non-functional, early-stage ACCs, suggesting a potentially targeted IGF1-SLC12A7 therapeutic opportunity for these tumors.

Genomic stratification and liquid biopsy in a rare adrenocortical carcinoma (ACC) case, with dual lung metastases

Adrenocortical carcinoma is a rare malignancy with a poor prognosis and few treatment options. Molecular characterization of this cancer remains limited. We present a case of an adrenocortical carcinoma (ACC) in a 37-yr-old female, with dual lung metastases identified 1 yr following commencement of adjuvant mitotane therapy. As standard therapeutic regimens are often unsuccessful in ACC, we undertook a comprehensive genomic study into this case to identify treatment options and monitor disease progress. We performed targeted and whole-genome sequencing of germline, primary tumor, and both metastatic tumors from this patient and monitored recurrence over 2 years using liquid biopsy for ctDNA and steroid hormone measurements. Sequencing revealed the primary and metastatic tumors were hyperhaploid, with extensive loss of heterozygosity but few structural rearrangements. Loss-of-function mutations were identified in MSH2, TP53, RB1, and PTEN, resulting in tumors with mismatch repair signatures and microsatellite instability. At the cellular level, tumors were populated by mitochondria-rich oncocytes. Longitudinal ctDNA mutation and hormone profiles were unable to detect micrometastatic disease, consistent with clinical indicators of disease remission. The molecular signatures in our ACC case suggested immunotherapy in the event of disease progression; however, the patient remains free of cancer. The extensive molecular analysis presented here could be applied to other rare and/or poorly stratified cancers to identify novel or repurpose existing therapeutic options, thereby broadly improving diagnoses, treatments, and prognoses.

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.

Pathobiology and genetics of adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare malignancy with an incidence worldwide of 0.7-2.0 cases/million/year. Initial staging is the most important factor in determining prognosis. If diagnosed early, complete surgical resection +/- adjuvant treatment can lead to 5-year survival of up to 80%. However, often it is diagnosed late and in advanced disease, 5-year survival is <15% with a high recurrence rate even after radical surgery. The mainstay of adjuvant treatment is with the drug mitotane. Mitotane has a specific cytotoxic effect on steroidogenic cells of the adrenal cortex, but despite this, progression through treatment is common. Developments in genetic analysis in the form of next-generation sequencing, aided by bioinformatics, have enabled high-throughput molecular characterisation of these tumours. This, in addition to a better appreciation of the processes of physiological, homeostatic self-renewal of the adrenal cortex, has furthered our understanding of the pathogenesis of this malignancy. In this review, we have detailed the pathobiology and genetic alterations in adrenocortical carcinoma by integrating current understanding of homeostasis and self-renewal in the normal adrenal cortex with molecular profiling of tumours from recent genetic analyses. Improved understanding of the mechanisms involved in self-renewal and stem cell hierarchy in normal human adrenal cortices, together with the identification of cell populations likely to be co-opted by oncogenic mutations, will enable further progress in the definition of the molecular pathways involved in the pathogenesis of ACC. The combination of these advances eventually will lead to the development of novel, effective and personalised strategies to eradicate molecularly annotated ACCs.

Unpacking the Pathogen Box-An Open Source Tool for Fighting Neglected Tropical Disease

The Pathogen Box is a 400-strong collection of drug-like compounds, selected for their potential against several of the world's most important neglected tropical diseases, including trypanosomiasis, leishmaniasis, cryptosporidiosis, toxoplasmosis, filariasis, schistosomiasis, dengue virus and trichuriasis, in addition to malaria and tuberculosis. This library represents an ensemble of numerous successful drug discovery programmes from around the globe, aimed at providing a powerful resource to stimulate open source drug discovery for diseases threatening the most vulnerable communities in the world. This review seeks to provide an in-depth analysis of the literature pertaining to the compounds in the Pathogen Box, including structure-activity relationship highlights, mechanisms of action, related compounds with reported activity against different diseases, and, where appropriate, discussion on the known and putative targets of compounds, thereby providing context and increasing the accessibility of the Pathogen Box to the drug discovery community.

Heat Shock Protein 90 as a Prognostic Marker and Therapeutic Target for Adrenocortical Carcinoma

Background: Adrenocortical carcinoma (ACC) is a rare tumor entity with restricted therapeutic opportunities. HSP90 (Heat Shock Protein 90) chaperone activity is fundamental for cell survival and contributes to different oncogenic signaling pathways. Indeed, agents targeting HSP90 function have shown therapeutic efficacy in several cancer types. We have examined the expression of HSP90 in different adrenal tumors and evaluated the use of HSP90 inhibitors in vitro as possible therapy for ACC. Methods: Immunohistochemical expression of HSP90 isoforms was investigated in different adrenocortical tumors and associated with clinical features. Additionally, a panel of N-terminal (17-allylamino-17-demethoxygeldanamycin (17-AAG), luminespib, and ganetespib) and C-terminal (novobiocin and silibinin) HSP90 inhibitors were tested on various ACC cell lines. Results: Within adrenocortical tumors, ACC samples exhibited the highest expression of HSP90β. Within a cohort of ACC patients, HSP90β expression levels were inversely correlated with recurrence-free and overall survival. In functional assays, among five different compounds tested luminespib and ganetespib induced a significant decrease in cell viability in single as well as in combined treatments with compounds of the clinically used EDP-M scheme (etoposide, doxorubicin, cisplatin, mitotane). Inhibition of cell viability correlated furthermore with a decrease in proliferation, in cell migration and an increase in apoptosis. Moreover, analysis of cancer pathways indicated a modulation of the ERK1/2-and AKT-pathways by luminespib and ganetespib treatment. Conclusions: Our findings emphasize HSP90 as a marker with prognostic impact and promising target with N-terminal HSP90 inhibitors as drugs with potential therapeutic efficacy toward ACC.

Primary malignant tumors of the adrenal glands

Malignancy must be considered in the management of adrenal lesions, including those incidentally identified on imaging studies. Adrenocortical carcinomas (ACCs) are rare tumors with an estimated annual incidence of 0.7-2 cases per year and a worldwide prevalence of 4-12 cases per million/year. However, a much higher incidence of these tumors (>15 times) has been demonstrated in south and southeastern Brazil. Most ACCs cause hypersecretion of steroids including glucocorticoids and androgens. ACC patients have a very poor prognosis with a 5-year overall survival (OS) below 30% in most series. Pheochromocytoma or paraganglioma (PPGL) is a metabolically active tumor originating from the chromaffin cells of the adrenal medulla. The incidence of PPGL is 0.2 to 0.9 cases per 100,000 individuals per year. Pheochromocytomas are present in approximately 4-7% of patients with adrenal incidentalomas. Classically, PPGL manifests as paroxysmal attacks of the following 4 symptoms: headaches, diaphoresis, palpitations, and severe hypertensive episodes. The diagnosis of malignant PPGL relies on the presence of local invasion or metastasis. In this review, we present the clinical and biochemical characteristics and pathogenesis of malignant primary lesions that affect the cortex and medulla of human adrenal glands.

Targeted Molecular Analysis in Adrenocortical Carcinomas: A Strategy Toward Improved Personalized Prognostication

CONTEXT

Adrenocortical carcinoma (ACC) has a heterogeneous prognosis, and current medical therapies have limited efficacy in its advanced stages. Genome-wide multiomics studies identified molecular patterns associated with clinical outcome.

OBJECTIVE

Here, we aimed at identifying a molecular signature useful for both personalized prognostic stratification and druggable targets, using methods applicable in clinical routine.

DESIGN

In total, 117 tumor samples from 107 patients with ACC were analyzed. Targeted next-generation sequencing of 160 genes and pyrosequencing of 4 genes were applied to formalin-fixed, paraffin-embedded (FFPE) specimens to detect point mutations, copy number alterations, and promoter region methylation. Molecular results were combined with clinical/histopathological parameters (tumor stage, age, symptoms, resection status, and Ki-67) to predict progression-free survival (PFS).

RESULTS

In addition to known driver mutations, we detected recurrent alterations in genes not previously associated with ACC (e.g., NOTCH1, CIC, KDM6A, BRCA1, BRCA2). Best prediction of PFS was obtained integrating molecular results (more than one somatic mutation, alterations in Wnt/β-catenin and p53 pathways, high methylation pattern) and clinical/histopathological parameters into a combined score (P < 0.0001, χ2 = 68.6). Accuracy of prediction for early disease progress was 83.3% (area under the receiver operating characteristic curve: 0.872, 95% confidence interval 0.80 to 0.94). Furthermore, 17 potentially targetable alterations were found in 64 patients (e.g., in CDK4, NOTCH1, NF1, MDM2, and EGFR and in DNA repair system).

CONCLUSIONS

This study demonstrates that molecular profiling of FFPE tumor samples improves prognostication of ACC beyond clinical/histopathological parameters and identifies new potential drug targets. These findings pave the way to precision medicine in this rare disease.

Pembrolizumab for metastatic adrenocortical carcinoma with high mutational burden: Two case reports

RATIONALE

In the setting of metastatic or locally advanced adrenocortical carcinoma, a limited number of therapies are available and their efficacy is generally below modest. The backbone of treatment remains surgery, even for metastatic disease, whenever it is possible, and mitotane. Chemotherapy can be used with limited results. A small subset of patients with adrenocortical carcinoma may have high mutational burden and harbor mutations in mismatch-repair genes.

PATIENT CONCERNS

We report a 40-year old and a 28-year-old female patients with metastatic adrenocortical carcinoma refractory to multiple treatments.

DIAGNOSIS

Next-generation sequencing detected high mutational burden (>10 mutations/megabase) in both patients, one of them with MSH2 mutation.

INTERVENTIONS

They were treated with pembrolizumab (100 to 200 mg every 3 weeks).

OUTCOMES

The patient harboring a MSH2 mutation experienced a long-term complete response after pembrolizumab, while the patient with high mutational burden and absence of mismatch repair deficiency did not have any response.

LESSONS

To the best of our knowledge, this is the first report in the literature of a durable complete response after pembrolizumab in a patient with metastatic adrenocortical carcinoma. Differences in therapy sequencing, possibly abscopal effect related to multiple previous radiotherapy exposition, predictive values of high mutational burden and mutations in mismatch-repair genes are discussed.

Over expression of DNA damage and cell cycle dependent proteins are associated with poor survival in patients with adrenocortical carcinoma

BACKGROUND

Adrenocortical carcinoma is a rare and aggressive malignancy with poor survival. With limited treatment options and high risk of relapse, identifying improved targets and therapies for adrenocortical carcinoma is important. We hypothesized that analysis of the database of The Cancer Genome Atlas could identify important novel biomarkers for improved therapeutic targeting of adrenocortical carcinoma.

METHODS

We utilized the University of Alabama interactive web resource to identify novel biomarkers observed in 79 adrenocortical carcinoma patients. Identified biomarkers were then examined for prognostic correlations using the cBioPortal and analyzed for statistical significance using STATA 13.0.

RESULTS

The Cancer Genome Atlas data mining in the University of Alabama interactive web resource for pathways associated with poor survival of patients with adrenocortical carcinoma revealed significant upregulation of genes involved in DNA damage and regulation of cell-cycle pathways, such as AURKA, AURKB, CDK1, CDK4, CDK6, PLK1, CHEK1, CHEK2, CDC7, BUB3, and MCM3 (P < .001-.05). On outcome correlation, greater expression levels of all the genes except CDK4 were associated with worse survival compared with medium or low levels of gene expression (P < .001 all) irrespective of age orsex. Consistent with our University of Alabama interactive web resource findings, data mining in the cBioPortal also revealed upregulation of genes regulating DNA-damage and cell cycle-related genes in 82% of patients (z score = 1.5).

CONCLUSION

Large data mining from the The Cancer Genome Atlas and cBioPortal databases identified overexpression of genes involved in DNA damage and those regulating pathways of the cell cycle, which correlated with poorer overall survival in adrenocortical carcinoma patients.

Receptor Tyrosine Kinase-Targeted Cancer Therapy

In the past two decades, several molecular targeted inhibitors have been developed and evaluated clinically to improve the survival of patients with cancer. Molecular targeted inhibitors inhibit the activities of pathogenic tyrosine kinases. Particularly, aberrant receptor tyrosine kinase (RTK) activation is a potential therapeutic target. An increased understanding of genetics, cellular biology and structural biology has led to the development of numerous important therapeutics. Pathogenic RTK mutations, deletions, translocations and amplification/over-expressions have been identified and are currently being examined for their roles in cancers. Therapies targeting RTKs are categorized as small-molecule inhibitors and monoclonal antibodies. Studies are underway to explore abnormalities in 20 types of RTK subfamilies in patients with cancer or other diseases. In this review, we describe representative RTKs important for developing cancer therapeutics and predicting or evaluated resistance mechanisms.

Mouse models in endocrine tumors

Endocrine and neuroendocrine tumors comprise a highly heterogeneous group of neoplasms that can arise from (neuro)endocrine cells, either from endocrine glands or from the widespread diffuse neuroendocrine system, and, consequently, are widely distributed throughout the body. Due to their diversity, heterogeneity and limited incidence, studying in detail the molecular and genetic alterations that underlie their development and progression is still a highly elusive task. This, in turn, hinders the discovery of novel therapeutic options for these tumors. To circumvent these limitations, numerous mouse models of endocrine and neuroendocrine tumors have been developed, characterized and used in pre-clinical, co-clinical (implemented in mouse models and patients simultaneously) and post-clinical studies, for they represent powerful and necessary tools in basic and translational tumor biology research. Indeed, different in vivo mouse models, including cell line-based xenografts (CDXs), patient-derived xenografts (PDXs) and genetically engineered mouse models (GEMs), have been used to delineate the development, progression and behavior of human tumors. Results gained with these in vivo models have facilitated the clinical application in patients of diverse breakthrough discoveries made in this field. Herein, we review the generation, characterization and translatability of the most prominent mouse models of endocrine and neuroendocrine tumors reported to date, as well as the most relevant clinical implications obtained for each endocrine and neuroendocrine tumor type.

Avelumab in patients with previously treated metastatic adrenocortical carcinoma: phase 1b results from the JAVELIN solid tumor trial

Background

We assessed the efficacy and safety of avelumab, an anti-programmed death ligand 1 (PD-L1) antibody, in patients with previously treated metastatic adrenocortical carcinoma (mACC).

Methods

In this phase 1b expansion cohort, patients with mACC and prior platinum-based therapy received avelumab at 10 mg/kg intravenously every 2 weeks. Continuation of mitotane was permitted; however, mitotane levels during the study were not recorded. Tumor response was assessed by Response Evaluation Criteria In Solid Tumors v1.1.

Results

Fifty patients received avelumab and were followed for a median of 16.5 months. Prior treatment included ≥2 lines in 74.0%; mitotane was continued in 50.0%. The objective response rate (ORR) was 6.0% (95% CI, 1.3% to 16.5%; partial response in 3 patients). Twenty-one patients (42.0%) had stable disease as best response (disease control rate, 48.0%). Median progression-free survival was 2.6 months (95% CI, 1.4 to 4.0), median overall survival (OS) was 10.6 months (95% CI, 7.4 to 15.0), and the 1-year OS rate was 43.4% (95% CI, 27.9% to 57.9%). In evaluable patients with PD-L1+ (n = 12) or PD-L1− (n = 30) tumors (≥5% tumor cell cutoff), ORR was 16.7% vs 3.3% (P = .192). Treatment-related adverse events (TRAEs) occurred in 82.0%; the most common were nausea (20.0%), fatigue (18.0%), hypothyroidism (14.0%), and pyrexia (14.0%). Grade 3 TRAEs occurred in 16.0%; no grade 4 to 5 TRAEs occurred. Twelve patients (24.0%) had an immune-related TRAE of any grade, which were grade 3 in 2 patients (4.0%): adrenal insufficiency (n = 1), and pneumonitis (n = 1).

Conclusions

Avelumab showed clinical activity and a manageable safety profile in patients with platinum-treated mACC.

Trial registration

Clinicaltrials.gov NCT01772004; registered January 21, 2013.

Electronic supplementary material

The online version of this article (10.1186/s40425-018-0424-9) contains supplementary material, which is available to authorized users.

Metastatic adrenocortical carcinoma displays higher mutation rate and tumor heterogeneity than primary tumors

Adrenocortical cancer (ACC) is a rare cancer with poor prognosis and high mortality due to metastatic disease. All reported genetic alterations have been in primary ACC, and it is unknown if there is molecular heterogeneity in ACC. Here, we report the genetic changes associated with metastatic ACC compared to primary ACCs and tumor heterogeneity. We performed whole-exome sequencing of 33 metastatic tumors. The overall mutation rate (per megabase) in metastatic tumors was 2.8-fold higher than primary ACC tumor samples. We found tumor heterogeneity among different metastatic sites in ACC and discovered recurrent mutations in several novel genes. We observed 37–57% overlap in genes that are mutated among different metastatic sites within the same patient. We also identified new therapeutic targets in recurrent and metastatic ACC not previously described in primary ACCs.

Adrenocortical cancer (ACC) is a rarely diagnosed and aggressive cancer whose metastatic form has been scarcely studied. Here, the authors study primary and metastatic ACC to investigate genomic heterogeneity, discovering higher mutation rates in metastatic lesions and novel recurrent mutations.

European Society of Endocrinology Clinical Practice Guidelines on the management of adrenocortical carcinoma in adults, in collaboration with the European Network for the Study of Adrenal Tumors

Adrenocortical carcinoma (ACC) is a rare and in most cases steroid hormone-producing tumor with variable prognosis. The purpose of these guidelines is to provide clinicians with best possible evidence-based recommendations for clinical management of patients with ACC based on the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. We predefined four main clinical questions, which we judged as particularly important for the management of ACC patients and performed systematic literature searches: (A) What is needed to diagnose an ACC by histopathology? (B) Which are the best prognostic markers in ACC? (C) Is adjuvant therapy able to prevent recurrent disease or reduce mortality after radical resection? (D) What is the best treatment option for macroscopically incompletely resected, recurrent or metastatic disease? Other relevant questions were discussed within the group. Selected Recommendations: (i) We recommend that all patients with suspected and proven ACC are discussed in a multidisciplinary expert team meeting. (ii) We recommend that every patient with (suspected) ACC should undergo careful clinical assessment, detailed endocrine work-up to identify autonomous hormone excess and adrenal-focused imaging. (iii) We recommend that adrenal surgery for (suspected) ACC should be performed only by surgeons experienced in adrenal and oncological surgery aiming at a complete en bloc resection (including resection of oligo-metastatic disease). (iv) We suggest that all suspected ACC should be reviewed by an expert adrenal pathologist using the Weiss score and providing Ki67 index. (v) We suggest adjuvant mitotane treatment in patients after radical surgery that have a perceived high risk of recurrence (ENSAT stage III, or R1 resection, or Ki67 >10%). (vi) For advanced ACC not amenable to complete surgical resection, local therapeutic measures (e.g. radiation therapy, radiofrequency ablation, chemoembolization) are of particular value. However, we suggest against the routine use of adrenal surgery in case of widespread metastatic disease. In these patients, we recommend either mitotane monotherapy or mitotane, etoposide, doxorubicin and cisplatin depending on prognostic parameters. In selected patients with a good response, surgery may be subsequently considered. (vii) In patients with recurrent disease and a disease-free interval of at least 12 months, in whom a complete resection/ablation seems feasible, we recommend surgery or alternatively other local therapies. Furthermore, we offer detailed recommendations about the management of mitotane treatment and other supportive therapies. Finally, we suggest directions for future research.

Therapeutic Targets for Adrenocortical Carcinoma in the Genomics Era

Adrenocortical carcinoma (ACC) is a rare and often fatal cancer, affecting ~1 person per million per year worldwide. Approximately 75% of patients with ACC eventually develop metastases and progress on the few available standard-of-care medical therapies, highlighting an incredible need for an improved understanding of the molecular biology of this disease. Although it has long been known that ACC is characterized by certain histological and genetic features (e.g., high mitotic activity, chromosomal instability, and overexpression of IGF2), only in the last two decades of genomics has the molecular landscape of ACC been more thoroughly characterized. In this review, we describe the findings of historical genetics and recent genomics studies on ACC and discuss how underlying concepts emerging from these studies contribute to the current model of critical pathways for adrenocortical carcinogenesis. Integrative synthesis across these studies reveals that ACC consists of three distinct molecular subtypes with divergent clinical outcomes and implicates differential regulation of Wnt signaling, cell cycle, DNA methylation, immune biology, and steroidogenesis in ACC biology. These cellular programs are pharmacologically targetable and may enable the development of therapeutic strategies to improve outcomes for patients facing this devastating disease.

Adjuvant and Neoadjuvant Therapy, Treatment for Advanced Disease, and Genetic Considerations for Adrenocortical Carcinoma: An Update from the SSO Endocrine and Head and Neck Disease Site Working Group

This is the second of a two-part review on adrenocortical carcinoma (ACC) management. While margin-negative resection provides the only potential cure for ACC, recurrence rates remain high. Furthermore, many patients present with locally advanced, unresectable tumors and/or diffuse metastases. As a result, selecting patients for adjuvant therapy and understanding systemic therapy options for advanced ACC is important. Herein, we detail the current literature supporting the use of adjuvant mitotane therapy, consideration of adjuvant radiation therapy, and utility of cytotoxic chemotherapy in patients with advanced disease. Ongoing investigation into molecular targeted agents, immunotherapy, and inhibitors of steroidogenesis for the treatment of ACC are also highlighted. Lastly, the importance of genetic counseling in patients with ACC is addressed as up to 10% of patients will have an identifiable hereditary syndrome.

A Phase I Dose-Escalation Study of Linsitinib (OSI-906), a Small-Molecule Dual Insulin-Like Growth Factor-1 Receptor/Insulin Receptor Kinase Inhibitor, in Combination with Irinotecan in Patients with Advanced Cancer

Lessons Learned.

The maximum tolerated dose of the combination of linsitinib and irinotecan is linsitinib 450 mg daily on days 1–3 every 7 days and irinotecan 125 mg/m² days 1 and 8 of a 21‐day cycle.

The adverse effects associated with the combination are not significantly increased beyond what is expected of each drug as a single agent.

Multiple negative trials of insulin‐like growth factor‐1 receptor inhibitors performed in unselected patient populations led to the early discontinuation of linistinib development and this trial.

Earlier integration of assessment of potential predictive biomarkers into clinical trials, as was planned in this study, is vital to the development of targeted therapies in oncology.

Background.

This phase I dose‐escalation study was designed to evaluate the safety and tolerability of the combination of irinotecan and insulin‐like growth factor‐1 receptor (IGF‐1R) inhibitor linsitinib in patients with advanced cancer refractory to standard therapy.

Methods.

Dose escalation in three specified dose levels was performed according to a standard 3 + 3 design. Dose levels were as follows: (a) linsitinib 400 mg and irinotecan 100 mg/m², (b) linsitinib 450 mg and irinotecan 100 mg/m², and (c) linsitinib 450 mg and irinotecan 125 mg/m². Linisitinib was administered once daily on days 1–3, 8–10, and 15–17, and irinotecan on days 1 and 8. Assessment of a candidate predictive biomarker was planned in all patients, with further evaluation in an expansion cohort of advanced colorectal cancer.

Results.

A total of 17 patients were treated, with 1 patient in both cohort 2 and 3 experiencing dose‐limiting toxicity. Linsitinib 450 mg and irinotecan 125 mg/m² was the maximum tolerated dose. Sixteen (94%) patients experienced at least one treatment‐related adverse event. Neutropenia was the only grade >3 toxicity (4%). No significant hyperglycemia or QT interval prolongation was noted. No objective responses were observed; 47% (n = 8) had stable disease with median duration of 5.25 months.

Conclusion.

Although the combination was determined safe, the study was halted due to termination of linsitinib development, and biomarker testing was not performed.