Nano-diamino-tetrac (NDAT) inhibits PD-L1 expression which is essential for proliferation in oral cancer cells

The Hypothalamic-Pituitary-Thyroid Axis Equivalent in Normal and Cancerous Oral Tissues: A Scoping Review

The hypothalamic-pituitary-thyroid (HPT) axis is crucial in regulating thyroid hormone levels that contribute to the development and homeostasis of the human body. Current literature supports the presence of a local HPT axis equivalent within keratinocytes of the skin, with thyroid hormones playing a potential role in cancer progression. However, this remains to be seen within oral tissue cells. An electronic search of Scopus and PubMed/Medline databases was conducted to identify all original publications that reported data on the production or effects of HPT axis components in normal or malignant cells of the oral cavity. The search identified 221 studies, of which 14 were eligible. Eight studies were retrospective analyses of clinical samples, one study involved both in vivo and in vitro experiments, and the remaining five studies were conducted in vitro using cell lines. The search identified evidence of effects of HPT components on oral cancer cells. However, there were limited data for the production of HPT axis components by oral tissues. We conclude that a possible role of the local HPT axis equivalent in the oral mucosa may not be established at present. The gaps in knowledge identified in this scoping review, particularly regarding the production of HPT components by oral tissues, warrant further investigation.

Effects of Anticancer Agent P-bi-TAT on Gene Expression Link the Integrin Thyroid Hormone Receptor to Expression of Stemness and Energy Metabolism Genes in Cancer Cells

Chemically modified forms of tetraiodothyroacetic acid (tetrac), an L-thyroxine derivative, have been shown to exert their anticancer activity at plasma membrane integrin αvβ3 of tumor cells. Via a specific hormone receptor on the integrin, tetrac-based therapeutic agents modulate expression of genes relevant to cancer cell proliferation, survival and energy metabolism. P-bi-TAT, a novel bivalent tetrac-containing synthetic compound has anticancer activity in vitro and in vivo against glioblastoma multiforme (GBM) and other types of human cancers. In the current study, microarray analysis was carried out on a primary culture of human GBM cells exposed to P-bi-TAT (10⁻⁶ tetrac equivalent) for 24 h. P-bi-TAT significantly affected expression of a large panel of genes implicated in cancer cell stemness, growth, survival and angiogenesis. Recent interest elsewhere in ATP synthase as a target in GBM cells caused us to focus attention on expression of genes involved in energy metabolism. Significantly downregulated transcripts included multiple energy-metabolism-related genes: electron transport chain genes ATP5A1 (ATP synthase 1), ATP51, ATP5G2, COX6B1 (cytochrome c oxidase subunit 6B1), NDUFA8 (NADH dehydrogenase (ubiquinone) FA8), NDUFV2I and other NDUF genes. The NDUF and ATP genes are also relevant to control of oxidative phosphorylation and transcription. Qualitatively similar actions of P-bi-TAT on expression of subsets of energy-metabolism-linked genes were also detected in established human GBM and pancreatic cancer cell lines. In conclusion, acting at αvβ3 integrin, P-bi-TAT caused downregulation in human cancer cells of expression of a large number of genes involved in electron transport and oxidative phosphorylation. These observations suggest that cell surface thyroid hormone receptors on αvβ3 regulate expression of genes relevant to tumor cell stemness and energy metabolism.

Heteronemin and tetrac derivatives suppress non-small cell lung cancer growth via ERK1/2 inhibition

The most common cancer, lung cancer, causes deaths worldwide. Most lung cancer patients have non-small cell lung carcinomas (NSCLCs) with a poor prognosis. The chemotherapies frequently cause resistance therefore search for new effective drugs for NSCLC patients is an urgent and essential issue. Deaminated thyroxine, tetraiodothyroacetic acid (tetrac), and its nano-analogue (NDAT) exhibit antiproliferative properties in several types of cancers. On the other hand, the most abundant secondary metabolite in the sponge Hippospongia sp., heteronemin, shows effective cytotoxic activity against different types of cancer cells. In the current study, we investigated the anticancer effects of heteronemin against two NSCLC cell lines, A549 and H1299 cells in vitro. Combined treatment with heteronemin and tetrac derivatives synergistically inhibited cancer cell growth and significantly modulated the ERK1/2 and STAT3 pathways in A549 cells but only ERK1/2 in H1299 cells. The combination treatments induce apoptosis via the caspases pathway in A549 cells but promote cell cycle arrest via CCND1 and PCNA inhibition in H1299 cells. In summary, these results suggest that combined treatment with heteronemin and tetrac derivatives could suppress signal transduction pathways essential for NSCLC cell growth. The synergetic effects can be used potentially as a therapeutic procedure for NSCLC patients.

Pharmacokinetics and biodistribution of a novel anticancer thyrointegrin αvβ3 antagonist: triazole modified tetraiodothyroacetic acid conjugated to polyethylene glycol (P-bi-TAT)

Abstract

We previously developed a triazole modified tetraiodothyroacetic acid (TAT) conjugated to a polyethylene glycol (PEG)-based thyrointegrin αvβ3 antagonist targeted compound, called P-bi-TAT. It exhibited potent anti-angiogenic and anticancer activities in vivo. The objective of the current study is to develop a quantitative bioanalytical method for P-bi-TAT using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and to elucidate pharmacokinetics (PK) and biodistribution of P-bi-TAT in animals. We used in-source collision-induced dissociation (CID) for ionization of P-bi-TAT in the positive mode, followed by multiple reaction monitoring (MRM) for quantification. P-bi-TAT was quantified using P-mono-TAT as an internal standard because of its similarity in structure and physicochemical properties to P-bi-TAT. The LOQ for P-bi-TAT was 30 ng/μL and the recovery efficiency was 76% with the developed method. Cmax and AUC results at different doses (1, 3, 10 mg/kg) in rats suggest that P-bi-TAT is dose-dependent within the range administered. Results for Cmax and AUC in monkeys at a low dose (25 mg/kg) were comparable to those in rats. Biodistribution of subcutaneously administered P-bi-TAT in the brain of rats ranged from 7.90 to 88.7 ng/g brain weight, and levels of P-bi-TAT in the brain were dose-dependent. The results suggest that P-bi-TAT is a potential candidate as a molecular-targeted anticancer therapeutic with blood-brain barrier permeability and acceptable PK parameters. Its accumulation in organs, toxicokinetic, and pharmacodynamics needs to be further investigated.

Graphical Abstract

Nano-Strategies Targeting the Integrin αvβ3 Network for Cancer Therapy

Integrin αvβ3, a cell surface receptor, participates in signaling transduction pathways in cancer cell proliferation and metastasis. Several ligands bind to integrin αvβ3 to regulate proliferation and metastasis in cancer cells. Crosstalk between the integrin and other signal transduction pathways also plays an important role in modulating cancer proliferation. Carcinoembryonic antigen cell adhesion molecule 6 (CEACAM6) activates the downstream integrin FAK to stimulate biological activities including cancer proliferation and metastasis. Blockage of signals related to integrin αvβ3 was shown to be a promising target for cancer therapies. 3,3′,5,5′-tetraiodothyroacetic acid (tetrac) completely binds to the integrin with the thyroid hormone to suppress cancer proliferation. The (E)-stilbene analog, resveratrol, also binds to integrin αvβ3 to inhibit cancer growth. Recently, nanotechnologies have been used in the biomedical field for detection and therapeutic purposes. In the current review, we show and evaluate the potentiation of the nanomaterial carrier RGD peptide, derivatives of PLGA-tetrac (NDAT), and nanoresveratrol targeting integrin αvβ3 in cancer therapies.

Role of thyroid hormone-integrin αvβ3-signal and therapeutic strategies in colorectal cancers

Thyroid hormone analogues-particularly, L-thyroxine (T₄) has been shown to be relevant to the functions of a variety of cancers. Integrin αvβ3 is a plasma membrane structural protein linked to signal transduction pathways that are critical to cancer cell proliferation and metastasis. Thyroid hormones, T₄ and to a less extend T₃ bind cell surface integrin αvβ3, to stimulate the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway to stimulate cancer cell growth. Thyroid hormone analogues also engage in crosstalk with the epidermal growth factor receptor (EGFR)-Ras pathway. EGFR signal generation and, downstream, transduction of Ras/Raf pathway signals contribute importantly to tumor cell progression. Mutated Ras oncogenes contribute to chemoresistance in colorectal carcinoma (CRC); chemoresistance may depend in part on the activity of ERK1/2 pathway. In this review, we evaluate the contribution of thyroxine interacting with integrin αvβ3 and crosstalking with EGFR/Ras signaling pathway non-genomically in CRC proliferation. Tetraiodothyroacetic acid (tetrac), the deaminated analogue of T₄, and its nano-derivative, NDAT, have anticancer functions, with effectiveness against CRC and other tumors. In Ras-mutant CRC cells, tetrac derivatives may overcome chemoresistance to other drugs via actions initiated at integrin αvβ3 and involving, downstream, the EGFR-Ras signaling pathways.

Nanotechnology-based drug delivery systems for enhanced diagnosis and therapy of oral cancer

Oral cancer is a common malignant life-threatening tumor. Despite some advances in traditional therapy, mortality and mobidity rates are high due to delayed diagnosis and ineffective treatment. Additionally, some patients inevitably suffer from various fatal adverse effects during the course of therapy. Therefore, it is imperative to develop novel methods to eradicate oral cancer cells with minimal adverse effects on normal cells. Nanotechnology is a promising and novel vehicle for the diagnosis and treatment of oral cancer with encouraging recent achievements. In this review, we present state-of-the-art nanotechnology-based drug delivery systems employed in the domain of oral cancer, especially for its enhanced diagnosis and therapy. We describe in detail the types of nanotechnology used in the management of oral cancer and summarize administration routes of nanodrugs. Finally, the potential and prospects of nanotechnology-based drug delivery systems as promising modalities of diagnosis and therapy of oral cancer are highlighted.

NDAT Targets PI3K-Mediated PD-L1 Upregulation to Reduce Proliferation in Gefitinib-Resistant Colorectal Cancer

The property of drug-resistance may attenuate clinical therapy in cancer cells, such as chemoresistance to gefitinib in colon cancer cells. In previous studies, overexpression of PD-L1 causes proliferation and metastasis in cancer cells; therefore, the PD-L1 pathway allows tumor cells to exert an adaptive resistance mechanism in vivo. Nano-diamino-tetrac (NDAT) has been shown to enhance the anti-proliferative effect induced by first-line chemotherapy in various types of cancer, including colorectal cancer (CRC). In this work, we attempted to explore whether NDAT could enhance the anti-proliferative effect of gefitinib in CRC and clarified the mechanism of their interaction. The MTT assay was utilized to detect a reduction in cell proliferation in four primary culture tumor cells treated with gefitinib or NDAT. The gene expression of PD-L1 and other tumor growth-related molecules were quantified by quantitative polymerase chain reaction (qPCR). Furthermore, the identification of PI3K and PD-L1 in treated CRC cells were detected by western blotting analysis. PD-L1 presentation in HCT116 xenograft tumors was characterized by specialized immunohistochemistry (IHC) and the hematoxylin and eosin stain (H&E stain). The correlations between the change in PD-L1 expression and tumorigenic characteristics were also analyzed. (3) The PD-L1 was highly expressed in Colo_160224 rather than in the other three primary CRC cells and HCT-116 cells. Moreover, the PD-L1 expression was decreased by gefitinib (1 µM and 10 µM) in two cells (Colo_150624 and 160426), but 10 µM gefitinib stimulated PD-L1 expression in gefitinib-resistant primary CRC Colo_160224 cells. Inactivated PI3K reduced PD-L1 expression and proliferation in CRC Colo_160224 cells. Gefitinib didn’t inhibit PD-L1 expression and PI3K activation in gefitinib-resistant Colo_160224 cells. However, NDAT inhibited PI3K activation as well as PD-L1 accumulation in gefitinib-resistant Colo_160224 cells. The combined treatment of NDAT and gefitinib inhibited pPI3K and PD-L1 expression and cell proliferation. Additionally, NDAT reduced PD-L1 accumulation and tumor growth in the HCT116 (K-RAS mutant) xenograft experiment. (4) Gefitinib might suppress PD-L1 expression but did not inhibit proliferation through PI3K in gefitinib-resistant primary CRC cells. However, NDAT not only down-regulated PD-L1 expression via blocking PI3K activation but also inhibited cell proliferation in gefitinib-resistant CRCs.

Insights into Nanomedicine for Immunotherapeutics in Squamous Cell Carcinoma of the head and neck

Immunotherapies such as immune checkpoint blockade benefit only a portion of patients with head and neck squamous cell carcinoma. The multidisciplinary field of nanomedicine is emerging as a promising strategy to achieve maximal anti-tumor effect in cancer immunotherapy and to turn non-responders into responders. Various methods have been developed to deliver therapeutic agents that can overcome bio-barriers, improve therapeutic delivery into the tumor and lymphoid tissues and reduce adverse effects in normal tissues. Additional modification strategies also have been employed to improve targeting and boost cytotoxic T cell-based immune responses. Here, we review the state-of-the-art use of nanotechnologies in the laboratory, in advanced preclinical phases as well as those running through clinical trials assessing their advantages and challenges.

Herbal Medicines Attenuate PD-L1 Expression to Induce Anti-Proliferation in Obesity-Related Cancers

Pro-inflammatory hormones and cytokines (leptin, tumor necrosis factor (TNF)-α, and interleukin (IL)-6) rise in obesity. Elevated levels of hormones and cytokines are linked with several comorbidities such as diabetes, heart disease, and cancer. The checkpoint programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) plays an important role in obesity and cancer proliferation. L-thyroxine (T₄) and steroid hormones up-regulate PD-L1 accumulation and promote inflammation in cancer cells and diabetics. On the other hand, resveratrol and other herbal medicines suppress PD-L1 accumulation and reduce diabetic effects. In addition, they induce anti-cancer proliferation in various types of cancer cells via different mechanisms. In the current review, we discuss new findings and visions into the antagonizing effects of hormones on herbal medicine-induced anti-cancer properties.

Thyroid hormone-induced expression of inflammatory cytokines interfere with resveratrol-induced anti-proliferation of oral cancer cells

Thyroid hormone, L-thyroxine (T₄), induces inflammatory genes expressions and promotes cancer growth. It also induces expression of the checkpoint programmed death-ligand 1 (PD-L1), which plays a vital role in cancer progression. On the other hand, resveratrol inhibits inflammatory genes expressions. Moreover, resveratrol increases nuclear inducible cyclooxygenase (COX)-2 accumulation, complexes with p53, and induces p53-dependent anti-proliferation. In this study, we investigated the effect of T₄ on resveratrol-induced anti-proliferation in oral cancer. T₄ increased the expression and cytoplasmic accumulation of PD-L1. Increased expressions of pro-inflammatory genes, interleukin (IL)-1β and transforming growth factor (TGF)-β1, were shown to stimulate PD-L1 expression. T₄ stimulated pro-inflammatory and proliferative genes expressions, and oral cancer cells proliferation. In contrast, resveratrol inhibited those genes and activated anti-proliferative genes. T₄ retained resveratrol-induced COX-2 in cytoplasm and prevented COX-2 nuclear accumulation when resveratrol treated cancer cells. A specific signal transducer and activator of transcription 3 (STAT3) inhibitor, S31-201, blocked T₄-induced inhibition and restored resveratrol-induced nuclear COX-2 accumulation. By inhibiting the T₄-activated STAT3 signal transduction axis with S31-201, resveratrol was able to sequentially reestablish COX-2/p53-dependent gene expressions and anti-proliferation. These findings provide a novel understanding of the inhibitory effects of T₄ on resveratrol-induced anticancer properties via the sequential expression of PD-L1 and inflammatory genes.

Tetrac as an anti-angiogenic agent in cancer

The thyroid hormones T3 and T4 have emerged as pro-angiogenic hormones with important implications for cancer management. Endogenous circulating hormone levels may help stimulate cancer progression and limit the effectiveness of anticancer therapy, though clinical data remain inconclusive. The capacity of thyroid hormones to modulate angiogenesis is mediated through non-canonical mechanisms initiated at the cell surface receptor integrin αvβ3. This integrin is predominantly expressed on tumour cells, proliferating endothelial cells and tumour stroma-associated cells, emphasising its potential relevance in angiogenesis and tumour biology. Thyroid hormone/integrin αvβ3 signalling results in the activation of intracellular pathways that are commonly associated with angiogenesis and are mediated through classical pro-angiogenic molecules such as vascular endothelial growth factor. The naturally occurring T4 analogue tetrac blocks the pro-angiogenic actions of thyroid hormones at the integrin receptor, in addition to agonist-independent anti-angiogenic effects. Tetrac reduces endothelial cell proliferation, migration and tube formation through a reduction in the transcription of vascular growth factors/growth factor receptors, hypoxia-inducible factor-1α, pro-angiogenic cytokines and a number of other pro-angiogenic genes, while at the same time stimulating the expression of endogenous angiogenesis inhibitors. It further modulates vascular growth factor activity by disrupting the crosstalk between integrin αvβ3 and adjacent growth factor receptors. Moreover, tetrac disrupts thyroid hormone-stimulated tumour recruitment, differentiation and the pro-angiogenic signalling of tumour stroma-associated mesenchymal stem cells. Tetrac affects tumour-associated angiogenesis via multiple mechanisms and interferes with other cancer cell survival pathways. In conjunction with its low toxicity and high tissue selectivity, tetrac is a promising candidate for clinical application.

Resveratrol antagonizes thyroid hormone-induced expression of checkpoint and proliferative genes in oral cancer cells

Background/purpose

Dysregulation of cell cycle checkpoint control may lead to the independence of growth regulating signals. Checkpoint protein such as the PD-1/PD-L1 immune checkpoint involving tumor cells and host immune defense lymphocytes is a well-studied therapeutic target in oncology. Acting at a cell surface receptor on plasma membrane integrin αvβ3, thyroxine stimulates intracellular accumulation of PD-L1 in cancer cells. Although resveratrol also binds to integrin αvβ3, it reduces PD-L1 expression.

Materials and methods

In current studies, we investigated the roles of resveratrol and thyroxine in regulating expression of proliferation-related genes and checkpoint genes, PD-L1, BTLA in two oral cancer cell lines.

Results

Thyroxine suppressed the expression of pro-apoptotic BAD but induced proliferative CCND1 expression in SSC-25 cells and OEC-M1 cells. It activated expression of PD-L1 and BTLA in both cell lines. On the other hand, resveratrol suppressed the expression of all. Alternatively, it activated BAD expression. Thus thyroxine induces checkpoint gene expression which may promote proliferation in cancer cells. Alternatively, resveratrol reverses the stimulatory effects of thyroid hormone to induce anti-proliferation.

Conclusion

These findings provide new insights into the antagonizing effect of resveratrol on the thyroxine-induced expression of checkpoint genes and proliferative genes in oral cancers.

The Role of Thyroid Hormones in Hepatocyte Proliferation and Liver Cancer

Thyroid hormones T3 and T4 (thyroxine) control a wide variety of effects related to development, differentiation, growth and metabolism, through their interaction with nuclear receptors. But thyroid hormones also produce non-genomic effects that typically start at the plasma membrane and are mediated mainly by integrin αvβ3, although other receptors such as TRα and TRβ are also able to elicit non-genomic responses. In the liver, the effects of thyroid hormones appear to be particularly important. The liver is able to regenerate, but it is subject to pathologies that may lead to cancer, such as fibrosis, cirrhosis, and non-alcoholic fatty liver disease. In addition, cancer cells undergo a reprogramming of their metabolism, resulting in drastic changes such as aerobic glycolysis instead of oxidative phosphorylation. As a consequence, the pyruvate kinase isoform M2, the rate-limiting enzyme of glycolysis, is dysregulated, and this is considered an important factor in tumorigenesis. Redox equilibrium is also important, in fact cancer cells give rise to the production of more reactive oxygen species (ROS) than normal cells. This increase may favor the survival and propagation of cancer cells. We evaluate the possible mechanisms involving the plasma membrane receptor integrin αvβ3 that may lead to cancer progression. Studying diseases that affect the liver and their experimental models may help to unravel the cellular pathways mediated by integrin αvβ3 that can lead to liver cancer. Inhibitors of integrin αvβ3 might represent a future therapeutic tool against liver cancer. We also include information on the possible role of exosomes in liver cancer, as well as on recent strategies such as organoids and spheroids, which may provide a new tool for research, drug discovery, and personalized medicine.

Tetrac and NDAT Induce Anti-proliferation via Integrin αvβ3 in Colorectal Cancers With Different K-RAS Status

Colorectal cancer is a serious medical problem in Taiwan. New, effective therapeutic approaches are needed. The selection of promising anticancer drugs and the transition from pre-clinical investigations to clinical trials are often challenging. The deaminated thyroid hormone analog (tetraiodothyroacetic acid, tetrac) and its nanoparticulate analog (NDAT) have been shown to have anti-proliferative activity in vitro and in xenograft model of different neoplasms, including colorectal cancers. However, mechanisms involved in tetrac- and NDAT-induced anti-proliferation in colorectal cancers are incompletely understood. We have investigated possible mechanisms of tetrac and NDAT action in colorectal cancer cells, using a perfusion bellows cell culture system that allows efficient, large-scale screening for mechanisms of drug actions on tumor cells. Although integrin αvβ3 in K-RAS wild type colorectal cancer HT-29 cells was far less than that in K-RAS mutant HCT116 cells, HT-29 was more sensitive to both tetrac and NDAT. Results also indicate that both tetrac and NDAT bind to tumor cell surface integrin αvβ3, and the agents may have different mechanisms of anti-proliferation in colorectal cancer cells. K-RAS status appears to play an important role in drug resistance that may be encountered in treatment with this drug combination.

In tumor cells, thyroid hormone analogues non-immunologically regulate PD-L1 and PD-1 accumulation that is anti-apoptotic

The PD-1/PD-L1 immune checkpoint involving tumor cells and host immune defense lymphocytes is a well-studied therapeutic target in oncology. That PD-1 and PD-L1 may have additional functions within tumor cells that are independent of the checkpoint is indicated by actions of a thyroid hormone analogue, L-thyroxine (T₄), on these checkpoint components. Acting at a cell surface receptor on plasma membrane integrin αvβ3, T₄ stimulates intracellular accumulation of PD-L1 in cancer cells. In these thyroid hormone-treated cells, T₄-induced PD-L1 is non-immunologically anti-apoptotic, blocking activation of p53. Several laboratories have also described accumulation of PD-1 in a variety of cancer cells, not just immune defense lymphocytes and macrophages. Preliminary observations indicate that T₄ stimulates intracellular accumulation of PD-1 in tumor cells, suggesting that, like PD-L1, PD-1 has non-immunologic roles in the setting of cancer. Where such roles are anti-apoptotic, thyroid hormone-directed cancer cell accumulation of PD-1 and PD-L1 may limit effectiveness of immunologic therapy directed at the immune checkpoint.