Anaplastic Thyroid Cancer Tumor Research Articles

Maintenance of magnesium homeostasis by NUF2 promotes protein synthesis and anaplastic thyroid cancer progression

Thyroid cancer is the most frequently observed endocrine-related malignancy among which anaplastic thyroid cancer (ATC) is the most fatal subtype. The synthesis of protein is active to satisfy the rapid growth of ATC tumor, but the mechanisms regulating protein synthesis are still unknown. Our research revealed that kinetochore protein NUF2 played an essential role in protein synthesis and drove the progression of ATC. The prognosis of patients with thyroid carcinoma was positively correlated with high NUF2 expression. Depletion of NUF2 in ATC cells notably inhibited the proliferation and induced apoptosis, while overexpression of NUF2 facilitated ATC cell viability and colony formation. Deletion of NUF2 significantly suppressed the growth and metastasis of ATC in vivo. Notably, knockdown of NUF2 epigenetically inhibited the expression of magnesium transporters through reducing the abundance of H3K4me3 at promoters, thereby reduced intracellular Mg2+ concentration. Furthermore, we found the deletion of NUF2 or magnesium transporters significantly inhibited the protein synthesis mediated by the PI3K/Akt/mTOR pathway. In conclusion, NUF2 functions as an emerging regulator for protein synthesis by maintaining the homeostasis of intracellular Mg2+, which finally drives ATC progression.

Disrupting glycolysis and DNA repair in anaplastic thyroid cancer with nucleus-targeting platinum nanoclusters

Cancer cells rely on aerobic glycolysis and DNA repair signals to drive tumor growth and develop drug resistance. Yet, fine-tuning aerobic glycolysis with the assist of nanotechnology, for example, dampening lactate dehydrogenase (LDH) for cancer cell metabolic reprograming remains to be investigated. Here we focus on anaplastic thyroid cancer (ATC) as an extremely malignant cancer with the high expression of LDH, and develop a pH-responsive and nucleus-targeting platinum nanocluster (Pt@TAT/sPEG) to simultaneously targets LDH and exacerbates DNA damage. Pt@TAT/sPEG effectively disrupts LDH activity, reducing lactate production and ATP levels, and meanwhile induces ROS production, DNA damage, and apoptosis in ATC tumor cells. We found Pt@TAT/sPEG also blocks nucleotide excision repair pathway and achieves effective tumor cell killing. In an orthotopic ATC xenograft model, Pt@TAT/sPEG demonstrates superior tumor growth suppression compared to Pt@sPEG and cisplatin. This nanostrategy offers a feasible approach to simultaneously inhibit glycolysis and DNA repair for metabolic reprogramming and enhanced tumor chemotherapy.

A distinct tumor microenvironment makes anaplastic thyroid cancer more lethal but immunotherapy sensitive than papillary thyroid cancer.

Both anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) originate from thyroid follicular epithelial cells, but ATC has a significantly worse prognosis and shows resistance to conventional therapies. However, clinical trials found that immunotherapy works better in ATC than late-stage PTC. Here, we used single-cell RNA sequencing (scRNA-Seq) to generate a single-cell atlas of thyroid cancer. Differences in ATC and PTC tumor microenvironment components (including malignant cells, stromal cells, and immune cells) leading to the polarized prognoses were identified. Intriguingly, we found that CXCL13+ T lymphocytes were enriched in ATC samples and might promote the development of early tertiary lymphoid structure (TLS). Last, murine experiments and scRNA-Seq analysis of a treated patient's tumor demonstrated that famitinib plus anti-PD-1 antibody could advance TLS in thyroid cancer. We displayed the cellular landscape of ATC and PTC, finding that CXCL13+ T cells and early TLS might make ATC more sensitive to immunotherapy.

Synergy between isobavachalcone and doxorubicin suppressed the progression of anaplastic thyroid cancer through ferroptosis activation.

The objective of this study was to explore the effects and mechanisms of the combination of isobavachalcone (IBC) and doxorubicin (DOX) on the progression of anaplastic thyroid cancer (ATC). Cell viability of 8505C and CAL62 cells was observed by CCK-8 assay. Kits were used to detect the presence of reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and cellular iron. Protein expression of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) was detected using western blot, and CD31 was detected through immunofluorescence. Tumor xenograft models of 8505C cells were constructed to observe the effect of IBC and DOX on ATC growth in vivo. The co-administration of IBC and DOX exhibited a synergistic effect of suppressing the growth of 8505C and CAL62 cells. The concurrent use of IBC and DOX resulted in elevated iron, ROS, and MDA levels, while reducing GSH levels and protein expression of SLC7A11 and GPX4. However, the Fer-1 ferroptosis inhibitor effectively counteracted this effect. In vitro and in vivo, the inhibitory effect on ATC cell proliferation and tumor growth was significantly enhanced by the combination of IBC and DOX. The combination of IBC and DOX can inhibit the growth of ATC by activating ferroptosis, and might prove to be a potent chemotherapy protocol for addressing ATC.

TRβ Agonism Induces Tumor Suppression and Enhances Drug Efficacy in Anaplastic Thyroid Cancer in Female Mice.

Thyroid hormone receptor beta (TRβ) is a recognized tumor suppressor in numerous solid cancers. The molecular signaling of TRβ has been elucidated in several cancer types through re-expression models. Remarkably, the potential impact of selective activation of endogenous TRβ on tumor progression remains largely unexplored. We used cell-based and in vivo assays to evaluate the effects of the TRβ agonist sobetirome (GC-1) on a particularly aggressive and dedifferentiated cancer, anaplastic thyroid cancer (ATC). Here we report that GC-1 reduced the tumorigenic phenotype, decreased cancer stem-like cell populations, and induced redifferentiation of the ATC cell lines with different mutational backgrounds. Of note, this selective activation of TRβ amplified the effects of therapeutic agents in blunting the aggressive cell phenotype and stem cell growth. In xenograft assays, GC-1 alone inhibited tumor growth and was as effective as the kinase inhibitor, sorafenib. These results indicate that selective activation of TRβ not only induces a tumor suppression program de novo but enhances the effectiveness of anticancer agents, revealing potential novel combination therapies for ATC and other aggressive solid tumors.

Thyroid Cancer, Neuroendocrine Tumor, Adrenal Adenoma, and Other Tumors in a Patient With a Germline PMS1 Mutation

Multiple tumors in the same patient suggest a genetic predisposition. Here, we report a patient who presented with several unusual types of malignant and benign tumors, presumably due to a pathogenic germline PMS1 mutation. A 69-year-old woman presented with a 2-year history of abdominal pain and diarrhea. A computed tomography scan of the abdomen revealed a gastrointestinal neuroendocrine tumor (GiNET) with liver metastases and a nonfunctional benign adrenal adenoma. Bilateral large lung nodules were thought to be also metastases from the GiNET but turned out to be differentiated thyroid cancer metastases, which later progressed to anaplastic thyroid cancer (ATC) and led to the patient's demise. A right sphenoid wing meningioma causing partial hypopituitarism was diagnosed during her evaluation. A mammogram and a breast ultrasound revealed a 0.3-cm left breast nodule. Due to the multiplicity of her tumors, whole exome sequencing was performed. This revealed a previously described PMS1 deletion mutation causing a frameshift and truncation (NM_000534c.1258delC, p.His420Ilefs*22) but no other pathogenic variant in other cancer genes. DNA isolated from the ATC tumor tissue showed loss of heterozygosity of the same mutation, highly suggestive of its pathogenic role in thyroid cancer and presumably other tumors. This case reports several tumors including thyroid cancer, GiNET, adrenal adenoma, meningioma, and breast nodule, likely due to the PMS1 mutation found in this patient.

Recent advances in the strategic incorporation of fluorine into new-generation taxoid anticancer agents

This account describes our recent progress on the strategic incorporation of fluorine and organofluorine moieties into new-generation taxoid anticancer agents for medicinal chemistry and chemical biology studies.In the case study 1, novel 3rd-generation fluorotaxoids bearing 3-OCF3 or 3-OCF2H group in the C2-benzoate moiety were designed, synthesized and examined for their anticancer activities. The potency of novel taxoids against drug-resistant cancer cell lines was 2–3 orders of magnitude higher than that of paclitaxel (PTX). Molecular modeling analysis indicated the favorable van der Waals interactions of OCF3 and OCHF2 groups in the binding site. Overall, taxoids bearing a OCHF2 group at the C2 benzoate position exhibited the highest potencies against multidrug-resistant (MDR) cancer cell lines and cancer stem cell (CSC)-enriched cell lines, indicating that the new 3rd-generation fluorotaxoids are promising candidates as chemotherapeutic agents.In the case study 2, novel 3rd-generation 3′-difluorovinyl (DFV)-taxoids, bearing 3-CF3O or 3-CHF2O group in the C2-benzoyl moiety, were designed, synthesized, and evaluated for their potencies and pharmacological properties. These new DFV-taxoids exhibited remarkable cytotoxicity against extremely drug-resistant cancer cell lines with subnanomolar IC50 values, indicating that these new DFV-taxoids can overcome MDR caused by the overexpression of Pgp and other ABC cassette transporters. The molecular docking analysis of new DFV-taxoids revealed that the 3′-DFV moiety and the 3-CF3O/3-CHF2O group of the C2-benzoate moiety are nicely accommodated to the deep hydrophobic pocket of the PTX/taxoid binding site in the β-tubulin, enabling an enhanced binding through unique attractive interactions between F/OCF3/OCHF2 and the protein. This enhancement in binding is reflected in the remarkable high potency of new 3rd-generation DFV-taxoids.In the case study 3.1, the therapeutic potential of new 3rd-generation DFV-taxoids in anaplastic thyroid cancer (ATC) cells was evaluated in vitro and in vivo. This study demonstrated that these new DFV-taxoids were more efficacious than PTX against ATC cell lines and tumor xenografts, as demonstrated by the efficient inhibition of cell proliferation and colony formation, induction of apoptosis via the mitotic arrest at the G2/M phase, as well as the suppression of tumorigenic potential in nude mice. Furthermore, tubulin polymerization assay and molecular docking analysis confirmed that these new DFV-taxoids promoted far more rapid polymerization of β-tubulin than PTX through stronger binding to tubulin/microtubules. Taken together, this study has indicated a promising therapeutic potential of these new DFV-taxoids against ATC.In the case study 3.2, DFV-OTX displayed potent cytotoxicity and effective induction of β-tubulin polymerization, as well as the G2/M phase arrest, leading to apoptosis in PTX-sensitive and PTX-resistant breast cancer cells. Furthermore, DFV-OTX clearly exhibited efficacy against MCF-7R and MDA-MB-231R tumor xenografts in mouse models. Thus, DFV-OTX effectively overcame PTX-resistance in MDA-MB-231R cells and tumor xenografts, wherein the drug resistance was attributed to ABCB1/ABCG2 upregulation. DFV-OTX was also effective against MCF-7R cells and tumor xenografts, which are PTX-resistant due to different MOA. Accordingly, DFV-OTX is a promising chemotherapeutic agent for the treatment of PTX-resistant cancers.Overall, these next-generation fluorotaxoids are promising candidates for highly potent chemotherapeutic agents, as well as payloads for tumor-targeting drug conjugates such as antibody-drug conjugates (ADCs).

Spontaneous Murine Model of Anaplastic Thyroid Cancer.

Anaplastic thyroid cancer (ATC) is a rare but lethal malignancy with a dismal prognosis. There is an urgent need for more in-depth research on the carcinogenesis and development of ATC, as well as therapeutic methods, since standard treatments are essentially depleted in ATC patients. However, low prevalence has hampered thorough clinical studies and the collection of tissue samples, so little progress has been achieved in creating effective treatments. We used genetic engineering to create a conditionally inducible ATC murine model (mATC) in a C57BL/6 background. The ATC murine model was genotyped by TPO-cre/ERT2; BrafCA/wt; Trp53ex2-10/ex2-10 and induced by intraperitoneal injection with tamoxifen. With the murine model, we investigated the tumor dynamics (tumor size ranged from 12.4 mm2 to 32.5 mm2 after 4 months of induction), survival (the median survival period was 130 days), and metastasis (lung metastases occurred in 91.6% of mice) curves and pathological features (characterized by Cd8, Foxp3, F4/80, Cd206, Ki67, and Caspase-3 immunohistochemical staining). The results indicated that spontaneous mATC possesses highly similar tumor dynamics and immunological microenvironment to human ATC tumors. In conclusion, with high similarity in pathophysiological features and unified genotypes, the mATC model resolved the shortage of clinical ATC tissue and sample heterogeneity to some extent. Therefore, it would facilitate the mechanism and translational studies of ATC and provide an approach to investigate the treatment potential of small molecular drugs and immunotherapy agents for ATC.

Lipid-Peptide-mRNA Nanoparticles Augment Radioiodine Uptake in Anaplastic Thyroid Cancer.

Restoring sodium iodide symporter (NIS) expression and function remains a major challenge for radioiodine therapy in anaplastic thyroid cancer (ATC). For more efficient delivery of messenger RNA (mRNA) to manipulate protein expression, a lipid-peptide-mRNA (LPm) nanoparticle (NP) is developed. The LPm NP is prepared by using amphiphilic peptides to assemble a peptide core and which is then coated with cationic lipids. An amphiphilic chimeric peptide, consisting of nine arginine and hydrophobic segments (6 histidine, C18 or cholesterol), is synthesized for adsorption of mRNA encoding NIS in RNase-free conditions. In vitro studies show that LP(R9H6) m NP is most efficient at delivering mRNA and can increase NIS expression in ATC cells by more than 10-fold. After intratumoral injection of NIS mRNA formulated in optimized LPm NP, NIS expression in subcutaneous ATC tumor tissue increases significantly in nude mice, resulting in more iodine 131 (131 I) accumulation in the tumor, thereby significantly inhibiting tumor growth. Overall, this work designs three arginine-rich peptide nanoparticles, contributing to the choice of liposome cores for gene delivery. LPm NP can serve as a promising adjunctive therapy for patients with ATC by restoring iodine affinity and enhancing the therapeutic efficacy of radioactive iodine.

TIM3 Expression in Anaplastic-Thyroid-Cancer-Infiltrating Macrophages: An Emerging Immunotherapeutic Target.

Anaplastic thyroid cancer (ATC) is a clinically aggressive form of undifferentiated thyroid cancer with limited treatment options. Immunotherapy for patients with ATC remains challenging. Tumor-associated macrophages (TAMs) constitute over 50% of ATC-infiltrating cells, and their presence is associated with a poor prognosis. Consequently, the development of new therapies targeting immune checkpoints in TAMs is considered a promising therapeutic approach for ATC. We have previously shown that soluble factors secreted by ATC cells induced pro-tumor M2-like polarization of human monocytes by upregulating the levels of the inhibitory receptor TIM3. Here, we extended our observations on ATC-cell-induced xenograft tumors. We observed a large number of immune cells infiltrating the ATC xenograft tumors. Significantly, 24-28% of CD45+ immune cells were macrophages (CD11b+ F4/80+). We further showed that 40% of macrophages were polarized toward a M2-like phenotype, as assessed by CD206 expression and by a significant increase in the Arg1/iNOS (M2/M1) ratio. Additionally, we found that ATC xenograft tumors had levels of TIM3 expression when determined by RT-PCR and immunofluorescence assays. Interestingly, we detected the expression of TIM3 in macrophages in ATC tumors by flow cytometry assays. Furthermore, TIM3 expression correlated with macrophage marker expression in human ATC. Our studies show that TIM3 is a newly identified immune checkpoint in macrophages. Since TIM3 is known as a negative immune regulator, it should be considered as a promising immunotherapeutic target for ATC.

Recognition of Key Genes in Human Anaplastic Thyroid Cancer via the Weighing Gene Coexpression Network.

Methods For determining pathways and key genes that have relation with development of ATC, differentially expressed genes (DEGs) from GSE33630 as well as GSE65144 expression microarray were screened. Furthermore, we also worked on carrying out the task of constructing a protein-protein interaction (PPI) network and the work of weighing gene coexpression network (WGCNA). DAVID was utilized for the performance of the Gene Ontology (GO) as well as KEGG pathway enrichment analyses for DEGs. We used TCGA THCA data and GSE53072 to further verify the hub gene and hub pathway. Results We came to the conclusion of the recognition of a total of 1063 genes as DEGs. Analysis regarding functional and pathway enrichment showed that there existed a notable enrichment of upregulated DEGs in the organization of extracellular structure and matrix organization, as well as in organelle fission and nuclear division. The downregulated DEG was markedly gathered in the thyroid hormone metabolic process and generation, as well as in the metabolic process of cellular modified amino acid. We identified 10 hub genes (CXCL8, CDH1, AURKA, CCNA2, FN1, CDK1, ITGAM, CDC20, MMP9, and KIF11) through the PPI network, which might be strongly linked to the carcinogenesis and the development of ATC. In the coexpression network, 6 modules that were relevant to ATC were recognized. The modules were related to the interaction of signaling pathway of p53, Hippo, PI3K/Akt, and ECM-receptor. This hub genes and hub pathway were further successfully validated as a potential biomarker for carcinogenesis and prediction in another database GSE53072. Conclusion To summarize, this research displayed an illustration of hub genes and pathways that had relation with ATC development, which suggested that DEGs and hub genes, recognized on the basis of bioinformatics analyses, were valuable in the diagnosis for patients with ATC.

Downregulation of AKT/mTOR signaling pathway for Salmonella-mediated autophagy in human anaplastic thyroid cancer.

Thyroid cancer has been known as the most common endocrine malignancy. Although majority of thyroid cancer types respond well to conventional treatment including surgery and radioactive iodine therapy, about 10% of those with differentiated thyroid cancer will present distant metastasis and will have persistent or recurrent disease. Even more serious is a rare type of thyroid cancer called anaplastic thyroid cancer (ATC), which accounts for about 1%, has been demonstrated as the most lethal and aggressive form of human malignancy. Unfortunately, these tumors are also frequently resistant to traditional therapy. Previous study have shown that Salmonella inhibits tumor growth, in part, by inducing autophagy - a cellular process that is important in the innate and adaptive immunity in response to viral or bacterial infection. In our study, we intended to investigate whether Salmonella can inhibit tumor growth by inducing autophagy, specifically in thyroid cancer and elucidate the possible molecular mechanism. In order to determine the signaling pathway involved in tumor cell autophagy, we used Salmonella to treat ATC cells line ASH-3 and KMH-2 in vitro. The autophagic markers, particularly autophagy-related gene 6 (Beclin-1), microtubule-associated protein 1A/1B-light chain 3 (LC3) and p62, were observed to be differentially expressed after infection with Salmonella indicating an activated autophagy in ATC cells. In addition, the protein expression levels of phospho-protein kinase B (P-AKT), phospho-mammalian targets of rapamycin (P-mTOR), phospho-p70 ribosomal s6 kinase (P-p70S6K) in tumor cells were decreased after Salmonella infection. In vivo, we also found that substantial cell numbers of Salmonella targeted tumor tissue, and regulated anti-tumor mechanisms. Our findings showed that Salmonella activated autophagic signaling pathway and inhibited ATC tumor growth via downregulation of AKT/mTOR pathway.

Thyroid Hormone Receptor Beta Inhibits PI3K-Akt-mTOR Signaling Axis in Anaplastic Thyroid Cancer via Genomic Mechanisms.

Thyroid cancer is the most common endocrine malignancy, and the global incidence has increased rapidly over the past few decades. Anaplastic thyroid cancer (ATC) is highly aggressive, dedifferentiated, and patients have a median survival of fewer than 6 months. Oncogenic alterations in ATC include aberrant phosphoinositide 3 kinase (PI3K) signaling through receptor tyrosine kinase (RTK) amplification, loss of phosphoinositide phosphatase expression and function, and protein kinase B (Akt) amplification. Furthermore, the loss of expression of the tumor suppressor thyroid hormone receptor beta (TRβ) is strongly associated with ATC. TRβ is known to suppress PI3K in follicular thyroid cancer and breast cancer by binding to the PI3K regulatory subunit p85α. However, the role of TRβ in suppressing PI3K signaling in ATC is not completely delineated. Here we report that TRβ indeed suppresses PI3K signaling in ATC cell lines through unreported genomic mechanisms, including a decrease in RTK expression and an increase in phosphoinositide and Akt phosphatase expression. Furthermore, the reintroduction and activation of TRβ in ATC cell lines enables an increase in the efficacy of the competitive PI3K inhibitors LY294002 and buparlisib on cell viability, migration, and suppression of PI3K signaling. These findings not only uncover additional tumor suppressor mechanisms of TRβ but shed light on the implication of TRβ status and activation on inhibitor efficacy in ATC tumors.

Augmentation of lenvatinib efficacy by topical treatment of miR-634 ointment in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the most lethal types of human tumors. Lenvatinib can improve the disease control and prognosis in patients with ATC. However, there is an unmet need to develop a therapeutically safer and non-invasive strategy that improves the efficacy of lenvatinib for advanced ATC tumors, which grow larger close to the skin. We previously demonstrated that the topical application of an ointment incorporating tumor suppressive microRNA (TS-miR), miR-634, is a useful strategy as a TS-miR therapeutics. Here, we found that the overexpression of miR-634 synergistically increased lenvatinib-induced cytotoxicity by concurrently downregulating multiple genes related to cytoprotective processes, including ASCT2, a glutamine transporter, in ATC cell lines. Furthermore, the topical application of a miR-634 ointment on subcutaneous tumors effectively augmented the anti-tumor effects of lenvatinib in an ATC xenograft mouse model. Thus, we propose topical treatment of a miR-634 ointment as a rational strategy for improving lenvatinib-based therapy for ATC.

Targeting Glycogen Metabolism as a Novel Therapeutic Approach in Anaplastic Thyroid Cancer

Effective treatment options for well-differentiated papillary (PTC) and follicular (FTC) thyroid cancers afford positive patient prognoses. The absence of effective interventions for the stem-like, dedifferentiated anaplastic thyroid cancer (ATC) results in poor patient outcomes with a mortality rate higher than all other endocrine cancers combined (1). While receptor tyrosine kinase inhibitors such as sorafenib can extend ATC patient survival, drug resistance and tumor reoccurrence often develop (2). Therefore, there is a critical need for more effective targeted therapies for ATC. Although the cell signaling landscape of ATC tumors is well described, very little is known about tumorigenic adaptations in ATC cellular metabolism. Tumors exhibit an increased consumption of glucose compared to normal tissues to fuel tumor progression. Some cancers meet this high glucose requirement by storing and breaking down glycogen. In our studies here, we show for the first time that normal thyroid, PTC, FTC, and ATC cells express genes necessary for glycogen metabolism. We confirm these observations in patient samples in normal thyroid and thyroid cancer patient samples via immunofluorescence in tissue microarrays. Furthermore, we detect intracellular glycogen stores in cell lines representing normal thyroid, PTC, FTC, and ATC cells. Importantly, we demonstrate that glycogen phosphorylase inhibitors result in accumulation of intracellular glycogen and induce subsequent apoptosis in ATC cells. We further show that glycogen phosphorylase inhibitors synergize with kinase inhibitors such as sorafenib and buparlisib to decrease ATC cell viability. Our work establishes glycogen metabolism as a novel metabolic process in thyroid cells that is associated with thyroid cancer dedifferentiation and provides insight to the effectiveness of inhibiting glycogen metabolism as a therapeutic strategy in ATC.

Efficacy of adavosertib therapy against anaplastic thyroid cancer.

Wee1 is a kinase that regulates the G2/M progression by the inhibition of CDK1, which is critical for ensuring DNA damage repair before initiation of mitotic entry. Targeting Wee1 may be a potential strategy in the treatment of anaplastic thyroid cancer, a rare but lethal disease. The therapeutic effects of adavosertib, a Wee1 inhibitor for anaplastic thyroid cancer was evaluated in this study. Adavosertib inhibited cell growth in three anaplastic thyroid cancer cell lines in a dose-dependent manner. Cell cycle analysis revealed cells were accumulated in the G2/M phase. Adavosertib induced caspase-3 activity and led to apoptosis. Adavosertib monotherapy showed significant retardation of the growth of two anaplastic thyroid cancer tumor models. The combination of adavosertib with dabrafenib and trametinib revealed strong synergism in vitro and demonstrated robust suppression of tumor growth in vivo in anaplastic thyroid cancer xenograft models with BRAFV600E mutation. The combination of adavosertib with either sorafenib or lenvatinib also demonstrated synergism in vitro and had strong inhibition of tumor growth in vivo in an anaplastic thyroid cancer xenograft model. No appreciable toxicity appeared in mice treated with either a single agent or combination treatment. Our findings suggest adavosertib holds the promise for the treatment of patients with anaplastic thyroid cancer.

Detecting Immune Response to Therapies Targeting PDL1 and BRAF by Using Ferumoxytol MRI and Macrin in Anaplastic Thyroid Cancer.

Background Anaplastic thyroid cancer (ATC) is aggressive with a poor prognosis, partly because of the immunosuppressive microenvironment created by tumor-associated macrophages (TAMs). Purpose To understand the relationship between TAM infiltration, tumor vascularization, and corresponding drug delivery by using ferumoxytol-enhanced MRI and macrin in an ATC mouse model. Materials and Methods ATC tumors were generated in 6-8-week-old female B6129SF1/J mice through intrathyroid injection to model orthotopic tumors, or intravenously to model hematogenous metastasis, and prospectively enrolled randomly into treatment cohorts (n = 94 total; August 1, 2018, to January 15, 2020). Mice were treated with vehicle or combined serine/threonine-protein kinase B-Raf (BRAF) kinase inhibitor (BRAFi) and anti-PDL1 antibody (aPDL1). A subset was cotreated with therapies, including an approximately 70-nm model drug delivery nanoparticle (DDNP) to target TAM, and an antibody-neutralizing colony stimulating factor 1 receptor (CSF1R). Imaging was performed at the macroscopic level with ferumoxytol-MRI and microscopically with macrin. Genetically engineered BrafV600E/WT p53-null allografts were used and complemented by a GFP-transgenic derivative and human xenografts. Tumor-bearing organs were processed by using tissue clearing and imaged with confocal microscopy and MRI. Two-tailed Wilcoxon tests were used for comparison (≥five per group). Results TAM levels were higher in orthotopic thyroid tumors compared with pulmonary metastatic lesions by 79% ± 23 (standard deviation; P < .001). These findings were concordant with ferumoxytol MRI, which showed 136% ± 88 higher uptake in thyroid lesions (P = .02) compared with lung lesions. BRAFi and aPDL1 combination therapy resulted in higher tumor DDNP delivery by 39% ± 14 in pulmonary lesions (P = .004). Compared with the untreated group, tumors following BRAFi, aPDL1, and CSF1R-blocking antibody combination therapy did not show greater levels of TAM or DDNP (P = .82). Conclusion In a mouse model of anaplastic thyroid cancer, ferumoxytol MRI showed 136% ± 88 greater uptake in orthotopic thyroid tumors compared with pulmonary lesions, which reflected high vascularization and greater tumor-associated macrophage (TAM) levels. Serine/threonine-protein kinase B-Raf inhibitor and anti-programmed death ligand 1 antibody elicited higher local TAM levels and 43% ± 20 greater therapeutic nanoparticle delivery but not higher vascularization in pulmonary tumors. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Luker in this issue.

Metformin Reduces Thyroid Cancer Tumor Growth in the Metastatic Niche of Bone by Inhibiting Osteoblastic RANKL Productions.

Background: Metformin has antitumoral actions in human cancers, including the thyroid, while its effects on metastatic lesions are unclear. Patients with bone metastasis (BM) from thyroid cancers have poor survival. Because metformin inhibits the activation of osteoclasts, which has essential roles in BM, the aim of this study was to investigate the therapeutic effects of metformin on thyroid cancer BM and osteoclast activation in the bone microenvironment. Methods: The anaplastic thyroid cancer (ATC) cell lines FRO and SW1736 were used to test the antitumoral effect of metformin in vitro and in vivo. A murine model of BM was established by intratibial injection of cancer cells. To mimic the BM microenvironment, osteoblasts were treated with conditioned media from the FRO (FRO-CM) and SW1736 (SW1736-CM) cells. Thyroid cancer patients with or without BM were recruited, and the serum receptor activator of nuclear factor kappa-B ligand (RANKL) levels was measured. Results: Metformin treatment significantly reduced the viabilities of the FRO and SW1736 cells in vitro and the tumor growth of SW1736 in vivo. In the murine model of BM, metformin delayed tumor growth in the bone and decreased the numbers of tartrate-resistant acid phosphatase-positive osteoclasts on the bone surface with reduced RANKL in the bone marrow. Furthermore, FRO- or SW1736-CM significantly increased the osteoblastic RANKL productions and activated osteoclast differentiation in whole marrow cultures, which were blocked by metformin treatment. Among 67 thyroid cancer patients, the serum RANKL levels were significantly increased in BM patients compared with patients with lung-only metastasis or no distant metastasis. In addition, the interleukin-6 superfamily in the FRO- or SW1736-CM stimulated STAT3 phosphorylation, which was inhibited by gp130 blocking. Metformin treatment decreased the FRO- or SW1736-CM-induced STAT3 phosphorylation by AMPK phosphorylation. Metformin also inhibited the FRO- or SW1736-CM-induced osteoclastic differentiation of bone marrow-derived monocyte/macrophage by RANK/c-Fos/NFATC1 signaling. Conclusions: In the microenvironment of BM, metformin effectively reduced ATC tumor growth by inhibiting cancer cell viability, blocking cancer cell-induced osteoblastic RANKL production, which further activated osteoclastogenesis, and directly reduced osteoclast differentiation. These multifactorial actions of metformin suggest that it has potential therapeutic effects in thyroid cancer BM.

Ketogenic diet combined with antioxidant N-acetylcysteine inhibits tumor growth in a mouse model of anaplastic thyroid cancer

BackgroundAnaplastic thyroid cancer is an aggressive and fatal malignancy. Many advanced cancers are characterized by glucose dependency, leading to oxidative stress and cellular proliferation. Therefore, we sought to determine if a low glucose environment (in vitro) or a ketogenic diet (in vivo) could inhibit anaplastic thyroid cancer tumor growth when combined with the antioxidant N-acetylcysteine. MethodsIn vivo, nude mice were injected with the anaplastic thyroid cancer cell line 8505C (n = 6/group). Group 1 was fed a standard diet; Group 2 was fed a ketogenic diet; Group 3 was given standard diet with N-acetylcysteine (40 mM in the drinking water); and Group 4 was fed ketogenic diet with N-acetylcysteine. Tumor volumes, ketones, and glucose were measured. H&E stains and immunohistochemistry for Ki-67 and Caspase 3 were performed on the tumors. In vitro, 8505C cells were cultured in high glucose (25 mM), low glucose (3 mM), high glucose plus N-acetylcysteine (200 uM), or low glucose plus N-acetylcysteine for 96 hours. We performed CyQUANT proliferation (Thermo Fisher Scientific, Waltham, MA), Seahorse glycolytic stress (Agilent, Santa Clara, CA), and reactive oxidative stress assays. ResultsKetogenic diet plus N-acetylcysteine decreased in vivo tumor volume compared to standard diet (22.5 ± 12.4 mm3 vs 147 ± 54.4 mm3, P < .05) and standard diet plus N-acetylcysteine (P < .05). Blood ketone levels were significantly higher for the mice in the ketogenic diet group compared to standard diet (1.74 mmol/L vs 0.38 mmol/L at week 5, P < .001). However, blood glucose levels were not significantly different between ketogenic diet and standard diet groups. Cells cultured in low glucose plus N-acetylcysteine had significantly reduced proliferation compared to high glucose (98.1 ± 5.0 relative fluorescence units vs 157.8 ± 2.1 relative fluorescence units, P < .001). Addition of N-acetylcysteine to low glucose lowered glycolysis function compared to high glucose (39.0 ± 2.2 mpH/min/cell vs 89.1 ± 13.2 mpH/min/cell, P < .001) and high glucose plus N-acetylcysteine (37.4 ± 2.5 mpH/min/cell vs 70.3 ± 3.3 mpH/min/cell, P < .001). Low glucose plus N-acetylcysteine decreased reactive oxidative stress compared to high glucose (119 ± 34.7 relative fluorescence units vs 277 ± 16.0 relative fluorescence units, P = .014). ConclusionThe combination of a ketogenic diet or glucose restriction with the antioxidant- N-acetylcysteine significantly reduced tumor growth in vivo and in vitro. Further studies are warranted to explore these metabolic therapies in anaplastic thyroid cancer.

A Pilot Study of Stereotactic Body Radiotherapy (SBRT) Combined with a PD-L1 Antibody Durvalumab (D) and a CTLA-4 antibody Tremelimumab (T) To Treat Metastatic Anaplastic Thyroid Cancer (ATC)

The prognosis of metastatic ATC is dismal and there are very limited treatment options. The thyroid is one of the most immunogenic organs in the body. PD-L1 is commonly expressed on ATC tumor cells and PD-1 in the inflammatory cells in the ATC microenvironment. However, antibodies to PD-1 as single agents have a poor record in this disease. Therefore, we designed this pilot study to add T to D and together with SBRT to augment their effects in hope to improve survival. This study evaluated the addition of T (75 mg every 4 weeks up to 4 doses) to D (1500 mg every 4 weeks). SBRT 9Gy x 3 fractions was given within the first 2 weeks of treatment to produce an “abscopal” effect. Major inclusion criteria: Metastatic ATC; ECOG PS 0-2; No prior immunotherapy; Last anti-cancer treatment > 7 days prior to starting study. Primary objective 1-year overall survival with target of ≥ 2 out of 12 patients. 12 patients were accrued. Male – 50%; Median PS 1; Median Age – 71 (49-82); Prior radiation to neck (75%); Prior chemotherapy (75%). MSI-High was noted in 2/11 subjects. BRAFV600E mutation in 3/12 subjects. There were 0 confirmed responses and only 1 subject with SD for 4 cycles or longer. Median time on treatment was 11 weeks (1-28+ weeks). MSI status did not affect treatment response. MSI-High patients were on treatment before progression for 8-14 weeks. Median overall survival was 14.5 weeks with only one person alive past 1 year. Neither the presence of a BRAF or p53 mutation appeared to affect either outcome. T/D with SBRT was not active in metastatic ATC. Future studies looking at other novel immunotherapy combinations in ATC should be evaluated. Biopsies done on study are being analyzed and will be presented.