Aberrant leptin signaling and overexpression of fibroblast growth factor receptor 1 (FGFR1) are both implicated in the pathogenesis of letrozole resistance in breast cancer (BCa), but it remains unknown whether these two pathways are involved in letrozole resistance in a coordinated manner. Here, we demonstrate that expression levels of the pre-B-cell leukemia homeobox transcription factor 3 (PBX3), a pioneer factor that governs divergent biological processes, were significantly upregulated in letrozole-resistant BCa cells and tissues, and this upregulation correlated to a poorer progression-free survival in patients. By leveraging a patient-derived xenograft model with pharmacological approaches, we demonstrated that leptin activated PBX3 expression in a STAT3 (signal transducer and activator of transcription 3)-dependent manner. Our loss- and gain-of-function study further showed that PBX3 attenuated response to letrozole by potentiating BCa cell survival and anchorage-independent growth in BCa cells. By profiling BCa cells with ectopic PBX3 expression, we revealed that PBX3 conferred letrozole resistance via transactivation of the FGFR1 signaling, and this molecular event must coordinate a synergistic transcription activation programs through interacting with MTA1-HDAC2 (metastasis-associated 1-histone deacetylase 2) complex. Overall, the available data reveal a novel role of leptin/PBX3 cascade linking energy homeostasis (i.e. hyperleptinemia) and endocrine therapy failure (i.e. letrozole resistance) in BCa.
Zhi-yuan Pang, Yun-tao Wei, Mu-yan Shang, Shuang Li, Yang Li, Quan-xiu Jin, Zhi-xuan Liao, Ming-ke Cui, Xiao-yan Liu, and Qiang Zhang
Patricia Borges de Souza and Chris McCabe
Radioiodine (RAI) therapy has been used to treat thyroid diseases for around 80 years, and yet it is only relatively recently that we are beginning to manipulate its use, as we understand more of the cellular complexities which govern its success. From the benign nature of hyperthyroidism to malignant thyroid carcinomas and their metastases, RAI has profoundly changed the management of thyroid disorders. However, the complex journey which has elicited this simple therapy is worth exploring.
Livia Lamartina, Nadège Anizan, Corinne Dupuy, Sophie Leboulleux, and Martin Schlumberger
Based on experimental data, the inhibition of the MAPkinase pathway in patients with radioiodine refractory thyroid cancer was capable to induce a redifferentiation. Preliminary data obtained on small series of patients are encouraging and this strategy might become an alternative treatment in those patients with a druggable mutation that induces a stimulation of the MAP kinase pathway. This is an active field of research to answer many still unresolved questions.
Guoliang Wang, Na Ren, Shengcai Wang, Zhang Xuexi, Yanzhen Li, Nian Sun, Qiaoyin Liu, Jie Zhang, Wenqi Song, and Xin Ni
It is uncertain whether serum TSH concentration is an independent risk factor for the malignancy of pediatric thyroid nodules. We sought for the association of serum TSH concentration with the malignancy of pediatric thyroid nodules and with the characteristics of pediatric thyroid cancer. A total of 219 pediatric thyroid nodule patients were collected retrospectively for 5 consecutive years. The medical records collected included sex, age, serum TSH concentration, thyroid autoantibody status, thyroid ultra-sonography parameters, histological type, and pathological TNM stages. The serum TSH concentrations were compared between benign and malignant nodules or corresponding subgroups. Binary logistic regression analysis was used to evaluate the correlation of TSH concentration with the malignancy of thyroid nodules and with the characteristics of pediatric thyroid cancer. There was no significant difference in TSH concentration between benign nodule and thyroid cancer in total subjects and various subgroups. The serum TSH level not correlated with the malignancy of thyroid nodules in univariate analysis, but negatively correlated with the malignancy of thyroid nodules (odds ratio = 0.856, p = 0.013) after adjusting for the patients’ sex, age, thyroid autoantibody status, and nodule size. The serum TSH level not correlated with the tumor characteristics in pediatric thyroid cancer patients. In conclusion, the serum TSH concentration seems not to be a carcinogenic factor in pediatric thyroid nodule patients, nor to be an independent risk factor for characteristics of pre-existing pediatric thyroid cancers.
Avaniyapuram Kannan Murugan, Abeer Al-Amr, Mysoon M Al-Ansari, Pulicat S. Manogaran, Hindi Al-Hindi, and Ali S Alzahrani
Thyroid cancer is a common endocrine neoplasm. Despite its good prognosis, it can lead to significant mortality due to metastasis and recurrence. However, the factors involved in metastasis are not well studied. Therefore, we selected matrix metalloproteinases 2 (MMP2) and determined whether it has any role in thyroid cancer. We sequenced the exons of MMP2 in 211 samples including 16 multi-nodular goiters and 195 differentiated thyroid cancers. We identified four non-synonymous single nucleotide polymorphisms (SNPs) of the MMP2 gene in 3.06% (6/195) thyroid cancers. Of the 4 MMP2 SNPs, 3 (75%) concomitantly had BRAFV600E. Hence, we speculated that the MMP2 SNPs may likely cooperate with BRAFV600E in promoting tumor aggressiveness. Overexpression of two MMP2 SNPs (P38L and T458I) exhibited markedly enhanced gelatinase activity with an intact dimerization and induced strong cortactin foci formation in HEK293T cells. Stable expression of the two MMP2 SNPs in BRAFV600E positive BCPAP cells dramatically enhanced cell proliferation, colony formation, and focus formation. Analysis of the morphology of MMP2 SNP bearing BCPAPV600E cells exhibited highly invasive phenotypes characterized by a high rate of wound healing and enhanced cell invasion compared with parental BCPAPV600E cells bearing vector. We also determined that BCPAPV600E cells stably transfected with MMP2 SNPs were highly sensitive to the treatment of BRAF inhibitor, PLX4720. Our study demonstrates that MMP2 SNPs could cooperate with BRAFV600E to promote oncogenicity, migration, and invasiveness of PTC cells. These results suggest that a subset of papillary thyroid cancer with this genetic makeup can benefit from BRAF-mediated therapeutic interventions.
Mintallah Haider, Satya Das, Taymeyah Al-Toubah, Eleonora Pelle, Ghassan El-Haddad, and Jonathan Strosberg
Peptide receptor radionuclide therapy (PRRT) using 177Lu-DOTATATE has been approved for the treatment of gastroenteropancreatic NETs. An understanding of benefits and risks is important for the appropriate implementation of this therapy. This review summarizes study data supporting the use of radiolabeled somatostatin analogs for the treatment of advanced NETs and highlights risks, including potential toxicities in specific populations. Key ongoing clinical trials, including randomized studies, are designed to better define the position of PRRT within the broader therapeutic landscape. Preclinical and early-phase human studies are focused on the development of novel somatostatin-receptor agonists and antagonists, new radionuclides, and radiosensitizing combination therapies.
James C Yao, Jonathan Strosberg, Nicola Fazio, Marianne E Pavel, Emily Bergsland, Philippe Ruszniewski, Daniel M Halperin, Daneng Li, Salvatore Tafuto, Nitya Raj, Davide Campana, Susumu Hijioka, Markus Raderer, Rosine Guimbaud, Pablo Gajate, Sara Pusceddu, Albert Reising, Evgeny Degtyarev, Mark Shilkrut, Simantini Eddy, and Simron Singh
Spartalizumab, a humanized anti-programmed death protein 1 (PD-1) MAB, was evaluated in patients with well-differentiated metastatic grade 1/2 neuroendocrine tumors (NET) and poorly differentiated gastroenteropancreatic neuroendocrine carcinomas (GEP-NEC). In this phase II, multicenter, single-arm study, patients received spartalizumab 400 mg every 4 weeks until confirmed disease progression or unacceptable toxicity. The primary endpoint was confirmed overall response rate (ORR) according to blinded independent review committee using response evaluation criteria in solid tumors 1.1. The study enrolled 95 patients in the NET group (30, 32 and 33 in the thoracic, gastrointestinal, and pancreatic cohorts, respectively), and 21 patients in the GEP-NEC group. The ORR was 7.4% (95% CI: 3.0, 14.6) in the NET group (thoracic, 16.7%; gastrointestinal, 3.1%; pancreatic, 3.0%), which was below the predefined success criterion of ≥10%, and 4.8% (95% CI: 0.1, 23.8) in the GEP-NEC group. In the NET and GEP-NEC groups, the 12-month progression-free survival was 19.5 and 0%, respectively, and the 12-month overall survival was 73.5 and 19.1%, respectively. The ORR was higher in patients with ≥1% PD-L1 expression in immune/tumor cells or ≥1% CD8+ cells at baseline. The most common adverse events considered as spartalizumab-related included fatigue (29.5%) and nausea (10.5%) in the NET group, and increased aspartate and alanine aminotransferases (each 14.3%) in the GEP-NEC group. The efficacy of spartalizumab was limited in this heterogeneous and heavily pre-treated population; however, the results in the thoracic cohort are encouraging and warrants further investigation. Adverse events were manageable and consistent with previous experience.
Elena Stauffer, Peter Weber, Theresa Heider, Claudia Dalke, Andreas Blutke, Axel Walch, Gerald Burgstaller, Nikko Brix, Kirsten Lauber, Horst Zitzelsberger, Kristian Unger, and Martin Selmansberger
Thyroid carcinoma incidence rates in western societies are among the fastest rising, compared to all malignant tumors over the past two decades. While risk factors such as age and exposure to ionizing radiation are known, early-state carcinogenic processes or pre-lesions are poorly understood or unknown. This study aims at the identification and characterization of early-state radiation-associated neoplastic processes by histologic and transcriptomic analyses of thyroid tissues derived from a mouse model. Comprehensive histological examination of 246 thyroids (164 exposed, 82 non-exposed) was carried out. Proliferative and normal tissues from exposed cases and normal tissue from non-exposed cases were collected by laser-capture microdissection, followed by RNAseq transcriptomic profiling using a low input 3′-library preparation protocol, differential gene expression analysis and functional association by gene set enrichment analysis. Nine exposed samples exhibited proliferative lesions, while none of the non-exposed samples showed histological abnormalities, indicating an association of ionizing radiation exposure with histological abnormalities. Activated immune response signaling and deregulated metabolic processes were observed in irradiated tissue with normal histology compared to normal tissue from non-exposed samples. Proliferative lesions compared to corresponding normal tissues showed enrichment for mainly proliferation-associated gene sets. Consistently, proliferative lesion samples from exposed mice showed elevated proliferation-associated signaling and deregulated metabolic processes compared to normal samples from non-exposed mice. Our findings suggest that a molecular deregulation may be detectable in histologically normal thyroid tissues and in early proliferative lesions in the frame of multi-step progression from irradiated normal tissue to tumorous lesions.