Galectin-3 Inhibitors Suppress Anoikis Resistance and Invasive Capacity in Thyroid Cancer Cells

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

An individualized protein-based prognostic model to stratify pediatric patients with papillary thyroid carcinoma

Pediatric papillary thyroid carcinomas (PPTCs) exhibit high inter-tumor heterogeneity and currently lack widely adopted recurrence risk stratification criteria. Hence, we propose a machine learning-based objective method to individually predict their recurrence risk. We retrospectively collect and evaluate the clinical factors and proteomes of 83 pediatric benign (PB), 85 pediatric malignant (PM) and 66 adult malignant (AM) nodules, and quantify 10,426 proteins by mass spectrometry. We find 243 and 121 significantly dysregulated proteins from PM vs. PB and PM vs. AM, respectively. Function and pathway analyses show the enhanced activation of the inflammatory and immune system in PM patients compared with the others. Nineteen proteins are selected to predict recurrence using a machine learning model with an accuracy of 88.24%. Our study generates a protein-based personalized prognostic prediction model that can stratify PPTC patients into high- or low-recurrence risk groups, providing a reference for clinical decision-making and individualized treatment.

Advances in targeted therapy and biomarker research in thyroid cancer

Driven by the intricacy of the illness and the need for individualized treatments, targeted therapy and biomarker research in thyroid cancer represent an important frontier in oncology. The variety of genetic changes associated with thyroid cancer demand more investigation to elucidate molecular details. This research is clinically significant since it can be used to develop customized treatment plans. A more focused approach is provided by targeted therapies, which target certain molecular targets such as mutant BRAF or RET proteins. This strategy minimizes collateral harm to healthy tissues and may also reduce adverse effects. Simultaneously, patient categorization based on molecular profiles is made possible by biomarker exploration, which allows for customized therapy regimens and maximizes therapeutic results. The benefits of targeted therapy and biomarker research go beyond their immediate clinical impact to encompass the whole cancer landscape. Comprehending the genetic underpinnings of thyroid cancer facilitates the creation of novel treatments that specifically target aberrant molecules. This advances the treatment of thyroid cancer and advances precision medicine, paving the way for the treatment of other cancers. Taken simply, more study on thyroid cancer is promising for better patient care. The concepts discovered during this investigation have the potential to completely transform the way that care is provided, bringing in a new era of personalized, precision medicine. This paradigm shift could improve the prognosis and quality of life for individuals with thyroid cancer and act as an inspiration for advances in other cancer types.

Inhibition of cancer cell‑platelet adhesion as a promising therapeutic target for preventing peritoneal dissemination of gastric cancer

Platelets form complexes with gastric cancer (GC) cells via direct contact, enhancing their malignant behavior. In the present study, the molecules responsible for GC cell-platelet interactions were examined and their therapeutic application in inhibiting the peritoneal dissemination of GC was investigated. First, the inhibitory effects of various candidate surface molecules were investigated on platelets and GC cells, such as C-type lectin-like receptor 2 (CLEC-2), glycoprotein VI (GPVI) and integrin αIIbβ3, in the platelet-induced enhancement of GC cell malignant potential. Second, the therapeutic effects of molecules responsible for the development and progression of GC were investigated in a mouse model of peritoneal dissemination. Platelet-induced enhancement of the migratory ability of GC cells was markedly inhibited by an anti-GPVI antibody and inhibitor of galectin-3, a GPVI ligand. However, neither the CLEC-2 inhibitor nor the integrin-blocking peptide significantly suppressed this enhanced migratory ability. In experiments using mouse GC cells and platelets, the migratory and invasive abilities enhanced by platelets were significantly suppressed by the anti-GPVI antibody and galectin-3 inhibitor. Furthermore, in vivo analyses demonstrated that the platelet-induced enhancement of peritoneal dissemination was significantly suppressed by the coadministration of anti-GPVI antibody and galectin-3 inhibitor, and was nearly eliminated by the combined treatment. The inhibition of adhesion resulting from GPVI-galectin-3 interaction may be a promising therapeutic strategy for preventing peritoneal dissemination in patients with GC.

Understanding and targeting anoikis in metastasis for cancer therapies

The development of effective treatments for cancers requires investigations for a more detailed and comprehensive understanding of the basic cellular mechanisms involved in carcinogenesis, cancer progression, and metastasis. One of those driving mechanisms is anoikis, a special type of apoptosis, which is induced by losing anchorage from the extracellular matrix (ECM). In other words, resisting death in detached cells (cells without ECM) forms an anoikis-resistant phenotype. Since the anoikis-resistance state compensates for the initial steps of cancer metastasis, this review aimed to discuss mechanisms of gaining anoikis/anoikis resistance phenotype in tumor cells. Finally, we highlighted the significance of anoikis in malignancies so as to provide clear insight into cancer diagnosis and therapy development.

Galectins and galectin-mediated autophagy regulation: new insights into targeted cancer therapy

Galectins are animal lectins with specific affinity for galactosides via the conserved carbohydrate recognition domains. Increasing studies recently have identified critical roles of galectin family members in tumor progression. Abnormal expression of galectins contributes to the proliferation, metastasis, epithelial-mesenchymal transformation (EMT), immunosuppression, radio-resistance and chemoresistance in various cancers, which has attracted cumulative clinical interest in galectin-based cancer treatment. Galectin family members have been reported to participate in autophagy regulation under physiological conditions and in non-tumoral diseases, and implication of galectins in multiple processes of carcinogenesis also involves regulation of autophagy, however, the relationship between galectins, autophagy and cancer remains largely unclear. In this review, we introduce the structure and function of galectins at the molecular level, summarize their engagements in autophagy and cancer progression, and also highlight the regulation of autophagy by galectins in cancer as well as the therapeutic potentials of galectin and autophagy-based strategies. Elaborating on the mechanism of galectin-regulated autophagy in cancers will accelerate the exploitation of galectins-autophagy targeted therapies in treatment for cancer.

Galectin functions in cancer-associated inflammation and thrombosis

Galectins are carbohydrate-binding proteins that regulate many cellular functions including proliferation, adhesion, migration, and phagocytosis. Increasing experimental and clinical evidence indicates that galectins influence many steps of cancer development by inducing the recruitment of immune cells to the inflammatory sites and modulating the effector function of neutrophils, monocytes, and lymphocytes. Recent studies described that different isoforms of galectins can induce platelet adhesion, aggregation, and granule release through the interaction with platelet-specific glycoproteins and integrins. Patients with cancer and/or deep-venous thrombosis have increased levels of galectins in the vasculature, suggesting that these proteins could be important contributors to cancer-associated inflammation and thrombosis. In this review, we summarize the pathological role of galectins in inflammatory and thrombotic events, influencing tumor progression and metastasis. We also discuss the potential of anti-cancer therapies targeting galectins in the pathological context of cancer-associated inflammation and thrombosis.

Targeting disordered-structured domain interactions in Galectin-3 based on NMR and enhanced MD

Intrinsically disordered regions (IDRs) are common and important functional domains in many proteins. However, IDRs are difficult to target for drug development due to the lack of defined structures that would facilitate the identification of possible drug-binding pockets. Galectin-3 is a carbohydrate-binding protein of which overexpression has been implicated in a wide variety of disorders, including cancer and inflammation. Apart from its carbohydrate-recognition/binding domain (CRD), Galectin-3 also contains a functionally important disordered N-terminal domain (NTD) that contacts the C-terminal domain (CTD) and could be a target for drug development. To overcome challenges involved in inhibitor design due to lack of structure and the highly dynamic nature of the NTD, we used a protocol combining nuclear magnetic resonance data from recombinant Galectin-3 with accelerated molecular dynamics (MD) simulations. This approach identified a pocket in the CTD with which the NTD makes frequent contact. In accordance with this model, mutation of residues L131 and L203 in this pocket caused loss of Galectin-3 agglutination ability, signifying the functional relevance of the cavity. In silico screening was used to design candidate inhibitory peptides targeting the newly discovered cavity, and experimental testing of only three of these yielded one peptide that inhibits the agglutination promoted by wild-type Galectin-3. NMR experiments further confirmed that this peptide indeed binds to a cavity in the CTD, not within the actual CRD. Our results show that it is possible to apply a combination of MD simulations and NMR experiments to precisely predict the binding interface of a disordered domain with a structured domain, and furthermore use this predicted interface for designing inhibitors. This procedure can potentially be extended to many other targets in which similar IDR interactions play a vital functional role.

ACLY inhibitors induce apoptosis and potentiate cytotoxic effects of sorafenib in thyroid cancer cells

PURPOSE

ATP-citrate lyase (ACLY) is a critical enzyme at the intersection of glucose and lipid metabolism. ACLY is often upregulated or activated in cancer cells to accelerate lipid synthesis and promote tumor progression. In this study, we aimed to explore the possibility of utilizing ACLY inhibition as a new strategy in the treatment of thyroid cancer.

METHODS

Bioinformatics analysis of the public datasets was performed. Thyroid cancer cells were treated with two different ACLY inhibitors, SB-204990 and NDI-091143.

RESULTS

Bioinformatics analysis revealed that ACLY expression was increased in anaplastic thyroid cancer. In thyroid cancer cell lines FTC-133 and 8505C, ACLY inhibitors suppressed monolayer cell growth and clonogenic ability in a dose-dependent and time-dependent manner. Flow cytometry analysis showed that ACLY inhibitors increased the proportion of sub-G1 cells in the cell cycle and the number of annexin V-positive cells. Immunoblotting confirmed caspase-3 activation and PARP1 cleavage following treatment with ACLY inhibitors. Compromised cell viability could be partially rescued by co-treatment with the pan-caspase inhibitor Z-VAD-FMK. Additionally, we showed that ACLY inhibitors impeded three-dimensional growth and cell invasion in thyroid cancer cells. Isobolograms and combination index analysis indicated that ACLY inhibitors synergistically potentiated the cytotoxicity rendered by sorafenib.

CONCLUSIONS

Targeting ACLY holds the potential for being a novel therapeutic strategy for thyroid cancer.

Propensity Score-Matched Analysis to Identify Pathways Associated with Loss of Sodium Iodide Symporter in Papillary Thyroid Cancer

Sodium iodide symporter (NIS) expression in thyroid follicular cells plays an important role in normal physiology and radioactive iodine therapy for thyroid cancer. Loss of NIS expression is often seen in thyroid cancers and may lead to radioiodine refractoriness. To explore novel mechanisms of NIS repression beyond oncogenic drivers, clinical and RNA-seq data from the thyroid cancer dataset of The Cancer Genome Atlas were analyzed. Propensity score matching was used to control for various genetic background factors. We found that tumoral NIS expression was negatively correlated with tumor size. Additionally, low NIS expression was the only factor associated with recurrence-free survival in a Cox multivariate regression analysis. After matching for clinicopathologic profiles and driver mutations, the principal component analysis revealed distinct gene expressions between the high and low NIS groups. Gene set enrichment analysis suggested the downregulation of hedgehog signaling, immune networks, and cell adhesions. Positively enriched pathways included DNA replication, nucleotide excision repair, MYC, and Wnt/β-catenin pathways. In summary, we identified several potential targets which could be exploited to rescue the loss of NIS expression and develop redifferentiation strategies to facilitate radioactive iodine therapy for thyroid cancer.

Galectin-3 regulates microglial activation and promotes inflammation through TLR4/MyD88/NF-kB in experimental autoimmune uveitis

Galectin-3, an attractive molecule of innate immunity, has been reported to be involved in the neuroinflammatory diseases. However, the role of Galectin-3 in autoimmune uveitis is still unclear. The purpose of this study was to investigate the effect and mechanism of Galectin-3 on microglial activation and inflammation of experimental autoimmune uveitis (EAU)_. We immunized female C57BL/6 J mice with IRBP_651-670 to induce EAU and the specific inhibitor was intravitreally injected in EAU mice. Disease severity was evaluated by clinical and histopathological scores. Immunofluorescence, western blot, qRT-PCR analysis and immunoprecipitation were used to detect the functional phenotypes and mechanisms on microglia after Galectin-3 inhibition. Our results showed that the expression of Galectin-3 was conspicuously increased in microglia of EAU retinas. The specific inhibitor of Galectin-3, TD139 was found to ameliorate the clinical and histological manifestations of EAU mice. In addition, TD139 reduced the expression of proinflammatory factors in vivo and vitro, which are related to the severity of uveitis. In mechanism, TD139 down-regulated the expression of TLR4 and MyD88, and then inhibited the activation of NF-κB p65 in microglia. In conclusion, Galectin-3 may play important roles in a variety of immune related diseases including autoimmune uveitis. Additionally, the inhibition of Galectin-3 may attenuate the microglial activation and inflammatory response through TLR4/MyD88/NF-κB pathway, highlighting a potential therapeutic target of Galectin-3 for autoimmune uveitis.

Cancer Studies under Space Conditions: Finding Answers Abroad

In this review article, we discuss the current state of knowledge in cancer research under real and simulated microgravity conditions and point out further research directions in this field. Outer space is an extremely hostile environment for human life, with radiation, microgravity, and vacuum posing significant hazards. Although the risk for cancer in astronauts is not clear, microgravity plays a thought-provoking role in the carcinogenesis of normal and cancer cells, causing such effects as multicellular spheroid formation, cytoskeleton rearrangement, alteration of gene expression and protein synthesis, and apoptosis. Furthermore, deleterious effects of radiation on cells seem to be accentuated under microgravity. Ground-based facilities have been used to study microgravity effects in addition to laborious experiments during parabolic flights or on space stations. Some potential 'gravisensors' have already been detected, and further identification of these mechanisms of mechanosensitivity could open up ways for therapeutic influence on cancer growth and apoptosis. These novel findings may help to find new effective cancer treatments and to provide health protection for humans on future long-term spaceflights and exploration of outer space.

Tumor metastasis: Mechanistic insights and therapeutic interventions

Cancer metastasis is responsible for the vast majority of cancer-related deaths worldwide. In contrast to numerous discoveries that reveal the detailed mechanisms leading to the formation of the primary tumor, the biological underpinnings of the metastatic disease remain poorly understood. Cancer metastasis is a complex process in which cancer cells escape from the primary tumor, settle, and grow at other parts of the body. Epithelial-mesenchymal transition and anoikis resistance of tumor cells are the main forces to promote metastasis, and multiple components in the tumor microenvironment and their complicated crosstalk with cancer cells are closely involved in distant metastasis. In addition to the three cornerstones of tumor treatment, surgery, chemotherapy, and radiotherapy, novel treatment approaches including targeted therapy and immunotherapy have been established in patients with metastatic cancer. Although the cancer survival rate has been greatly improved over the years, it is still far from satisfactory. In this review, we provided an overview of the metastasis process, summarized the cellular and molecular mechanisms involved in the dissemination and distant metastasis of cancer cells, and reviewed the important advances in interventions for cancer metastasis.