Differentiated thyroid carcinoma (DTC) combined with congenital hypothyroidism (CH) is a rare situation, and there is no well-established causal relationship. CH is a common congenital endocrine, while DTC occurring in childhood represents 0.4–3% of all malignancies at this stage of life. The association of CH with DTC could be related to dyshormonogenetic goiter (DHG) or developmental abnormalities. This review will explore the clinical features and the molecular mechanisms potentially associated with the appearance of DTC in CH: sporadic somatic driver mutations, chronic increase of thyroid-stimulating hormone (TSH) levels, higher concentrations of hydrogen peroxide (H2O2), cell division cycle associated 8 (Borelain/CDC8) gene mutations, and in others genes associated with CH – either alone or associated with the mechanisms involved in dyshormonogenesis. There are some pitfalls in the diagnosis of thyroid cancer in patients with CH with nodular goiter, as the proper cytological diagnosis of nodules of patients with dyshormonogenesis might be demanding due to the specific architectural and cytological appearance, which may lead to an erroneous interpretation of malignancy. The purpose of this article is to suggest an analytical framework that embraces the fundamental relationships between the various aspects of CH and CDT. In face of this scenario, the entire genetic and epigenetic context, the complex functioning, and cross talk of cell signaling may determine cellular mechanisms promoting both the maintenance of the differentiated state of the thyroid follicular cell and the disruption of its homeostasis leading to cancer. Whereas, the exact mechanisms for thyroid cancer development in CH remain to be elucidated.
Gustavo Penna, Ileana G S Rubio, Ester Saraiva Brust, Juliana Cazarin, Fabio Hecht, Nina Ramalho Alkmim, Kamilla M A Brandão Rajão, and Helton Estrela Ramos
Ville Paakinaho and Jorma J Palvimo
Steroid receptors (SRs) constitute an important class of signal-dependent transcription factors (TFs). They regulate a variety of key biological processes and are crucial drug targets in many disease states. In particular, estrogen (ER) and androgen receptors (AR) drive the development and progression of breast and prostate cancer, respectively. Thus, they represent the main specific drug targets in these diseases. Recent evidence has suggested that the crosstalk between signal-dependent TFs is an important step in the reprogramming of chromatin sites; a signal-activated TF can expand or restrict the chromatin binding of another TF. This crosstalk can rewire gene programs and thus alter biological processes and influence the progression of disease. Lately, it has been postulated that there may be an important crosstalk between the AR and the ER with other SRs. Especially, progesterone (PR) and glucocorticoid receptor (GR) can reprogram chromatin binding of ER and gene programs in breast cancer cells. Furthermore, GR can take the place of AR in antiandrogen-resistant prostate cancer cells. Here, we review the current knowledge of the crosstalk between SRs in breast and prostate cancers. We emphasize how the activity of ER and AR on chromatin can be modulated by other SRs on a genome-wide scale. We also highlight the knowledge gaps in the interplay of SRs and their complex interactions with other signaling pathways and suggest how to experimentally fill in these gaps.
Jonathan M Fussey, Robin N Beaumont, Andrew R Wood, Bijay Vaidya, Joel Smith, and Jessica Tyrrell
Evidence from observational studies suggests a positive association between serum thyroid-stimulating hormone (TSH) levels and differentiated thyroid carcinoma. However, the cause-effect relationship is poorly understood, and these studies are susceptible to bias and confounding. Using Mendelian randomization (MR) methodology, this study aimed to investigate the causal role of TSH in both benign thyroid nodules and thyroid cancer in up to 451,025 participants in the UK Biobank. Hospital Episode Statistics and Cancer Registry databases were used to identify 462 patients with differentiated thyroid carcinoma and 2031 patients with benign nodular thyroid disease. MR methods using genetic variants associated with serum TSH were used to test causal relationships between TSH and the two disease outcomes. We observed evidence of an inverse association between TSH levels and both thyroid cancer and benign nodular thyroid disease. Two-sample MR suggested that one standard deviation higher genetically instrumented TSH (approximately 0.8 mlU/L) resulted in an 80% reduction of risk of benign nodular disease (OR 0.20; 95% CI 0.10–0.41) and a 50% reduction of risk of thyroid cancer (OR 0.50; 95% CI 0.27–0.92). In keeping with other recently published studies, our results refute a causal role for TSH in both benign nodular thyroid disease and thyroid cancer, with increasing genetically instrumented TSH resulting in a lower risk of both diseases.
Lena Weindl, Imke Atreya, Peter Dietrich, Sabine Neubeck, Markus F Neurath, and Marianne Pavel
Neuroendocrine neoplasms (NENs) represent a rare and heterogeneous group of malignancies, sharing features of both neural and endocrine cells. NENs G3 appear as a highly aggressive subset with a poor prognosis and limited therapeutic options. The small-molecule inhibitor of the WEE1 tyrosine kinase, adavosertib (AZD1775), has previously demonstrated potent anti-tumor effects on various types of cancer in preclinical and clinical studies. However, the role of adavosertib in NENs G3 had remained elusive. We evaluated the effects of adavosertib on pancreatic (BON-1, QGP-1) and bronchopulmonary (NCI-H720) neuroendocrine tumor cell lines applying 2D and 3D spheroid models. We newly demonstrated that adavosertib is sufficient to reduce cell viability and proliferation in neuroendocrine cell lines with features of high-grade NENs. As underlying mechanisms, we identified adavosertib-mediated DNA double-strand breaks and a G2/M cell cycle checkpoint abrogation leading into mitotic catastrophe and cancer cell apoptosis. Silencing of WEE1 via siRNA transfection resulted in a phenotype similar to adavosertib treatment. Together, inhibition of the WEE1 tyrosine kinase applying adavosertib on NENs G3 outlines a promising novel therapeutic strategy.
Andrew E Greenstein, Mouhammed Amir Habra, Subhagya A Wadekar, and Andreas Grauer
Elevated glucocorticoid (GC) activity may limit tumor immune response and immune checkpoint inhibitor (ICI) efficacy. Adrenocortical carcinoma (ACC) provides a unique test case to assess correlates of GC activity, as approximately half of ACC patients exhibit excess GC production (GC+). ACC multi-omics were analyzed to identify molecular consequences of GC+ and assess the rationale for combining the glucocorticoid receptor (GR) antagonist relacorilant with an ICI. GC status, mRNA expression, and DNA mutation and methylation data from 71 adrenal tumors were accessed via The Cancer Genome Atlas. Expression of 858 genes differed significantly between GC− and GC+ ACC cases. KEGG pathway analysis showed higher gene expression of three pathways involved in steroid synthesis and secretion in GC+ cases. Fifteen pathways, most related to NK cells and other immune activity, showed lower expression. Hypomethylation was primarily observed in the steroid synthesis pathways. Tumor-infiltrating CD4+ memory (P = 0.003), CD8+ memory (P < 0.001), and NKT-cells (P = 0.014) were depleted in GC+ cases; tumor-associated neutrophils were enriched (P < 0.001). Given the pronounced differences between GC+ and GC− ACC, the effects of cortisol on NK cells were assessed in vitro (NK cells from human PBMCs stimulated with IL-2 or IL-12/15). Cortisol suppressed, and relacorilant restored, NK cell activation, proliferation, and direct tumor cell killing. Thus, GR antagonism may increase the abundance and function of NK and other immune cells in the tumor microenvironment, promoting immune response in GC+ ACC and other malignancies with GC+. This hypothesis will be tested in a phase 1 trial of relacorilant + ICI.
Nicholas Mitsiades and Salma Kaochar
Based on pioneering work by Huggins, Hodges and others, hormonal therapies have been established as an effective approach for advanced prostate cancer (PC) for the past eight decades. However, it quickly became evident that androgen deprivation therapy (ADT) via surgical or medical castration accomplishes inadequate inhibition of the androgen receptor (AR) axis, with clinical resistance inevitably emerging due to adrenal and intratumoral sources of androgens and other mechanisms. Early efforts to augment ADT by adding adrenal-targeting agents (aminoglutethimide, ketoconazole) or AR antagonists (flutamide, bicalutamide, nilutamide, cyproterone) failed to achieve overall survival (OS) benefits, although they did exhibit some evidence of limited clinical activity. More recently, four new androgen receptor signaling inhibitors (ARSIs) successfully entered clinical practice. Specifically, the CYP17 inhibitor abiraterone acetate and the second generation AR antagonists (enzalutamide, apalutamide and darolutamide) achieved OS benefits for PC patients, confirmed the importance of reactivated AR signaling in castration-resistant PC and validated important concepts that had been proposed in the field several decades ago but had remained so far unproven, including adrenal-targeted therapy and combined androgen blockade. The past decade has seen steady advances toward more comprehensive AR axis targeting. Now the question is raised whether we have accomplished the maximum AR axis inhibition possible or there is still room for improvement. This review, marking the 80-year anniversary of ADT and 10-year anniversary of successful ARSIs, examines their current clinical use and discusses future directions, in particular combination regimens, to maximize their efficacy, delay emergence of resistance and improve patient outcomes.
Amina Zoubeidi and Paramita M Ghosh
In this issue of Endocrine-Related Cancer, we are celebrating the 80th anniversary of hormone ablation as treatment for metastatic prostate cancer. Our understanding has evolved from the observation that androgen withdrawal, either surgical or pharmacological, resulted in prostatic atrophy in animal models, to its application in patients, to investigation of the mysterious way in which prostate cancer escapes androgen dependence. We are now in an era of novel AR pathway inhibitors, the combination of androgen ablation with chemotherapy, PARP inhibitors, immunotherapies, guided radiotherapy, and novel drug application based upon genetic testing of individual tumors. In this special issue, we bring together a collection of eight reviews that cover not only the history of 80 years of progress after the initial identification of androgen ablation as an effective treatment of prostate cancer, but subsequent improvements in the understanding of the biology of the disease, development of novel treatment paradigms, resistance to those treatments and disease progression following that resistance.
Mark P Labrecque, Joshi J Alumkal, Ilsa M Coleman, Peter S Nelson, and Colm Morrissey
The use of androgen deprivation therapy and second-line anti-androgens in prostate cancer has led to the emergence of tumors employing multiple androgen receptor (AR)-dependent and AR-independent mechanisms to resist AR-targeted therapies in castration-resistant prostate cancer (CRPC). While the AR signaling axis remains the cornerstone for therapeutic development in CRPC, a clearer understanding of the heterogeneous biology of CRPC tumors is needed for innovative treatment strategies. In this review, we discuss the characteristics of CRPC tumors that lack AR activity and the temporal and spatial considerations for the conversion of an AR-dependent to an AR-independent tumor type. We describe the more prevalent treatment-emergent phenotypes arising in the CRPC disease continuum, including amphicrine, AR-low, double-negative, neuroendocrine and small cell phenotypes. We discuss the association between the loss of AR activity and tumor plasticity with a focus on the roles of transcription factors like SOX2, DNA methylation, alternative splicing, and the activity of epigenetic modifiers like EZH2, BRD4, LSD1, and the nBAF complex in conversion to a neuroendocrine or small cell phenotype in CRPC. We hypothesize that only a subset of CRPC tumors have the propensity for tumor plasticity and conversion to the neuroendocrine phenotype and outline how we might target these plastic and emergent phenotypes in CRPC. In conclusion, we assess the current and future avenues for treatment and determine that the heterogeneity of CRPCs lacking AR activity will require diverse treatment approaches.
Maria L Sandoval, Ammoren Dohm, and Kosj Yamoah
The current standard for the management of locally advanced and early stage metastatic prostate cancer relies on a backbone of androgen deprivation therapy (ADT) combined with radiotherapy (RT), a regimen that at a glance appears relatively straightforward. The emergence of newer diagnostic, genomic and imaging modalities have allowed for better disease risk-stratification and opened avenues for the development of more patient-centered treatment strategies. This review aims to highlight the central role of RT as part of a multi-modal approach and discuss established and emerging data for the management of locally advanced disease, biochemical recurrence, and oligometastatic disease, as well as the use of immunotherapies and radio-isotopes. This review will also briefly discuss ongoing clinical trials that provide new insights into the paradigm shift in the management of locally advanced prostate cancer.
Cristina Gurizzan, Manuel Zamparini, Marco Volante, Valeria Tovazzi, Vito Amoroso, Francesca Consoli, Fausto Petrelli, Salvatore Grisanti, Paolo Bossi, and Alfredo Berruti
Intrathyroidal thymic carcinoma (ITC) is a rare thyroid tumor that resembles thymic carcinoma, for which there are no recommendations on diagnostic and therapeutic approaches. We performed a pooled analysis of published ITC cases to describe the natural history of this disease and identify prognostic factors. We performed a systematic review of histopathological-confirmed ITC cases published in the literature in English. The following keywords were used: 'intrathyroidal thymic carcinoma', 'carcinoma showing thymus-like differentiation', 'CASTLE tumor', 'thyroid carcinoma showing thymus like differentiation'. Fifty eligible publications were identified, providing data from 132 patients, plus a case diagnosed at our institution. Median disease-free survival (DFS) of this patient series was 144 months (range 91–197), while median overall survival (OS) was not reached. Upfront surgery was performed in 97% of patients and 24% of them experienced disease recurrence after a median of 19 months (range 13–25). Complaining of major symptoms, as a sign of more advanced local stage, was the only prognostic factor significantly associated with a higher risk of death at multivariate analysis (HR 4.903, 95% CI: 1.092–22.008, P = 0.038). Postoperative radiation therapy was not associated with prognosis, while not enough data were available to assess the efficacy of chemotherapy. ITC is a rather indolent disease and ITC patients have a relatively good prognosis. Surgery is the mainstay of therapy. Survival outcome of patients depends on tumor burden and complete surgical resection. Postoperative radiation effect seems to be negligible. Data on the efficacy of chemotherapy in advanced patients are lacking.