M2-like tumor-associated macrophages-secreted Wnt1 and Wnt3a promotes dedifferentiation and metastasis via activating β-catenin pathway in thyroid cancer

Arjunolic acid inhibits Wnt3a-mediated macrophage M2 polarization to suppress osteosarcoma progression

BACKGROUND

Osteosarcoma (OS) is a bone tumor characterized by a high recurrence rate and poor prognosis. Arjunolic acid (AA), the most abundant triterpene component in Cyclocarya paliurus, is reported to have anti-tumor effects. Its specific role in OS is still unknown, which we aim to investigate in our study.

METHODS

An OS mouse model was established to investigate the effects of AA. Subsequently, M2 macrophages and M0 macrophages pretreated with AA were co-cultured with OS cells. The impact of AA on OS cell behavior (proliferation, apoptosis, migration, and invasion) was evaluated via EdU staining, flow cytometry, and Transwell assays. Concurrently, the expression of M1- and M2-associated genes (CD86, CD163, IL-6, Arg1) was quantified to assess AA's regulatory role in macrophages within the tumor microenvironment (TME). Knockdown or overexpression of Wnt3a in AA-treated M0 macrophages to determine whether AA modulates Wnt3a-mediated M2 polarization, which was further validated in vivo.

RESULTS

In vivo, AA inhibited tumor progression in OS mice. Concurrently, AA-treated macrophages inhibited OS cell malignant behavior, and AA inhibited OS cell-mediated macrophage M2-type polarization. Mechanistically, AA inhibits the malignant behavior of OS cells and inhibits tumor progression in OS mice by suppressing Wnt3a-mediated macrophage M2 polarization. Additionally, AA-induced macrophage conversion to a pro-inflammatory phenotype in the TME of OS mice.

CONCLUSION

Our experiment demonstrated that AA from Cyclocarya paliurus inhibits Wnt3a-mediated M2 macrophage polarization to suppress the progression of osteosarcoma, providing a pharmacological foundation for developing therapies against OS.

BPS causes abnormal blastocyst development by inhibiting cell proliferation

In recent years, the escalating global utilization of bisphenol S (BPS) has raised growing concerns regarding its potential adverse effects on human health. However, the effects of BPS exposure on mammalian embryonic development and the associated molecular mechanisms remain inadequately characterized. In this study, we systematically investigated BPS toxicity in mouse embryogenesis by exposing embryos to graded concentrations (0-25 μg/mL). Our results demonstrated a dose-dependent impairment in early embryonic quality following BPS exposure. Specifically, treatment with 10 μg/mL and 15 μg/mL BPS significantly reduced blastocyst formation rates, diminished implantation potential, decreased total cell number of blastocysts, and caused cell fate determination imbalance. Mechanistic studies revealed that under BPS exposure, the massive accumulation of reactive oxygen species (ROS) in embryos induced cell cycle arrest and enhanced autophagy. It is worth noting that the reduction in the total cell number within blastocysts under BPS exposure manifested independently of the apoptotic pathway, as evidenced by the absence of upregulation in caspase 3/7 activity levels and TUNEL-positive signals. Our data collectively reveal that BPS disrupts early embryogenesis through ROS-driven cell cycle dysregulation and erroneous cell fate determination, culminating in compromised blastocyst developmental competence. This research unveils previously unrecognized mechanisms underlying BPS embryotoxicity, emphasizing essential parameters for evaluating chemical reproductive hazards in safety assessments.

Multiple-omics analysis reveals a dedifferentiation-immune loop in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is known for its diverse cell types and resistance to standard treatments, highlighting the importance of understanding its tumor microenvironment (TME) for improved prognostic accuracy and therapeutic innovation. Our study used a multi-omics approach to analyze the ICC TME in both human and mouse samples, linking survival outcomes to the complex cellular interactions within the TME. We discovered a dedifferentiation phenomenon in ICC cells driven by the Yes-associated protein (YAP) pathway, influenced by tumor-associated macrophages (TAMs). Conversely, ICC cells promoted an immunosuppressive environment in TAMs. Targeting TAMs in a transgenic mouse model disrupted this loop, enhancing T cell responses and suggesting a novel immunotherapy avenue for ICC. Our findings reveal a reciprocal dedifferentiation-immunosuppression loop between ICC cells and TAMs, advocating TAM targeting as a promising therapy and highlighting the potential of macrophage modulation in ICC treatment.

Analysis of thyroid carcinoma composition and spatial architecture in the progression of dedifferentiation, lymphatic metastasis, and gastric metastasis

BACKGROUND

Gastrointestinal metastases are rare in patients with thyroid carcinoma (TC), and their underlying mechanisms remain unclear. Thus, in this study, we aimed to explore the spatial distribution characteristics of TCs and associated gastrointestinal metastatic cells.

METHODS

We used spatial transcriptomics to generate an atlas that captures spatial gene expression patterns in papillary thyroid cancer (PTC), anaplastic thyroid carcinoma (ATC), ATC-associated lymphatic metastasis (ATC-LM), and rare ATC-associated gastric metastasis (ATC-GM).

RESULTS

We demonstrated that tumor-specific myeloid cells with high SFRP4 expression were correlated with TC dedifferentiation and poor prognosis. Moreover, we validated their close localization to CD44+ tissue stem cells using immunofluorescence staining and spatial transcriptomics. We also demonstrated that ATC-LM and ATC-GM tissues exhibited high levels of CD44+PKHD1L1+ cells, which could serve as markers for these two pathological types.

CONCLUSIONS

These findings highlight the dynamic changes in cell composition, intercellular communication, and potential markers associated with TC dedifferentiation and distant metastasis. Further research based on our findings may contribute to improving diagnostic and therapeutic strategies for patients with TC.

Immune cells in thyroid adenoma and carcinoma: uncovering a hidden value of assessing tumor-host interplay and its potential application in thyroid cytopathology

Introduction

Although the role of tumor immune microenvironment (TIME) in thyroid cancer is well established, little data exists about the differences in immune cell presence in thyroid adenomas and carcinomas. We assume that immune cell density could be an additional diagnostic criterion for differentiating benign and malignant tumors in thyroid aspirates.

Aim

The current study compared the immune contexture of thyroid adenoma (TA) and thyroid carcinoma (TC) in histological and cytological specimens of III-V categories.

Materials and methods

This pilot study included 72 cases (36 of TA and 36 of TC) with verified histological diagnosis and pre-operative cytology corresponding to categories III, IV and V according to the Bethesda system for reporting thyroid cytology. The number of CD8+, CD68+ and CD163+ cells was assessed in histological samples of TA and TC with further comparison to cytological specimens. Besides, the expression of STAT6 and SMAD4 as potential regulators of TIME was evaluated in the study.

Results

TC demonstrated an immune-rich profile representing abundant tumor-associated CD8+ lymphocytes, CD68 and CD163+ macrophages. In contrast, TA represented mostly a low immune cell infiltration. The higher immunogenicity of TC was accompanied by the more profound expression of STAT6 and SMAD4 in tumor cells. The number of immune cells in cytological specimens correlated with CD8+ (r = 0.693; p < 0.001) and CD163+ cells (r = 0.559; p < 0.001) in histological samples, reflecting the differences in the tumor immune microenvironment between benign and malignant thyroid neoplasms.

Conclusion

TC demonstrated high immunogenicity compared to TA, which correlated to the number of immune cells in cytological specimens. The number of immune cells in thyroid cytology samples could be an additional criterion in cytological diagnostics for III-V Bethesda categories. Further investigations are needed to validate the findings of the study.

Tumor-associated macrophages induce epithelial-mesenchymal transition and promote lung metastasis in breast cancer by activating the IL-6/STAT3/TGM2 axis

Breast cancer is one of the most common tumors in the world and metastasis is the major cause of tumor-related death. Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and often associated with cancer metastasis. Nevertheless, the mechanism by which TAMs regulate breast cancer metastasis remain unclear. In this study, we found that transglutaminase 2 (TGM2) could serve as a crucial target in the modulation of TAMs-induced epithelial-mesenchymal transition (EMT) and invasion of breast cancer cells. Further analysis revealed that IL-6 secreted from TAMs, which was capable of inducing TGM2 expression through the activation of the JAK/STAT3 signaling pathway. Subsequent luciferase reporter assays demonstrated that STAT3 binds to the TGM2 promoter region, thereby transcriptionally enhancing TGM2 expression. In conclusion, our current research has identified the IL-6/STAT3/TGM2 axis as a pivotal regulator in breast tumorigenesis caused by TAMs, presenting a novel target for the treatment of breast cancer.

Crosstalk between thyroid CSCs and immune cells: basic principles and clinical implications

Thyroid cancer has become the most common endocrine malignancy. Although the majority of differentiated thyroid cancers have a favorable prognosis, advanced thyroid cancers, iodine-refractory thyroid cancers, and highly malignant undifferentiated carcinomas still face a serious challenge of poor prognosis and even death. Cancer stem cells are recognized as one of the central drivers of tumor evolution, recurrence and treatment resistance. A fresh viewpoint on the oncological aspects of thyroid cancer, including proliferation, invasion, recurrence, metastasis, and therapeutic resistance, has been made possible by the recent thorough understanding of the defining and developing features as well as the plasticity of thyroid cancer stem cells (TCSCs). The above characteristics of TCSCs are complicated and regulated by cell-intrinsic mechanisms (including activation of key stem signaling pathways, somatic cell dedifferentiation, etc.) and cell-extrinsic mechanisms. The complex communication between TCSCs and the infiltrating immune cell populations in the tumor microenvironment (TME) is a paradigm for cell-extrinsic regulators. This review introduces the current advances in the studies of TCSCs, including the origin of TCSCs, the intrinsic signaling pathways regulating the stemness of TCSCs, and emerging biomarkers; We further highlight the underlying principles of bidirectional crosstalk between TCSCs and immune cell populations driving thyroid cancer progression, recurrence, or metastasis, including the specific mechanisms by which immune cells maintain the stemness and other properties of TCSCs and how TCSCs reshape the immune microenvironmental landscape to create an immune evasive and pro-tumorigenic ecological niche. Finally, we outline promising strategies and challenges for targeting key programs in the TCSCs-immune cell crosstalk process to treat thyroid cancer.

CD163+ Tumor-Associated Macrophage Recruitment Predicts Papillary Thyroid Cancer Recurrence

INTRODUCTION

Skewed immune response plays a pivotal role in tumor progression. Systemic inflammatory responses represented by combined peripheral leukocyte fractions are prognostic predictors of multiple cancers, including thyroid cancer. We previously reported the prognostic significance of lymphocyte-to-monocyte ratio (LMR) in curatively resected papillary thyroid cancer (PTC). Therefore, this study aimed to analyze immune cell profiles in the tumor microenvironment and their association with LMR in curatively resected PTC.

MATERIALS AND METHODS

The immune cell profiles of primary tumors in 162 patients with curatively resected PTC were analyzed clinicopathologically. Immunohistochemistry of tumor-associated macrophages (TAMs), myeloid-derived suppressor cells, and lymphocytes was performed using CD163, CD33, and CD3 antibodies, respectively. Prognostic analysis and correlation assays were performed using the immunocyte profiles. The gene expression of tumor-derived chemokines was assessed using a The Cancer Genome Atlas database.

RESULTS

Patients with a higher density of CD163+ TAMs exhibited a significantly worse prognosis than their counterparts (10-y recurrence-free survival: 80.9% versus 91.2%, P = 0.011). Multivariate prognostic analyses revealed that high CD163+ cell density (P = 0.011), low preoperative LMR (P = 0.003), pN1b (P = 0.005), and high thyroglobulin level (P = 0.038) were independent predictors of recurrence. High CD163+ cell density had a prognostic impact on stage II and III PTC. Interestingly, high CD163+ cell density correlated with low LMR and high monocyte fraction in peripheral blood. Indeed, the expression of TAM-inducible, tumor-derived chemokines is increased in the The Cancer Genome Atlas database.

CONCLUSIONS

A high density of infiltrated CD163+ TAMs predicts recurrence in correlation with low LMR and circulating monocyte accumulation. Thus, TAMs should be considered when assessing advanced PTC.

Relationship of microvascular density and tumor-associated macrophages with orofacial squamous cell carcinoma progression

OBJECTIVE

The current study aimed to investigate the characteristics of tumor-associated macrophages (TAMs) and their association with microvascular density (MVD) in tumor progression in different grades of orofacial squamous cell carcinoma (OSCC) in the Pakistani population.

STUDY DESIGN

This prospective study included 234 patients with oral cancer reported at different hospitals in Pakistan diagnosed with OSCC. Tumors were graded on the Anneroth grading system and the association between the frequency of TAMs and MVD was examined in vivo. The macrophages visible through immunohistochemistry for CD68 and the microvessels observed through immunohistochemistry for CD34 were manually counted in 3 high-power fields.

RESULTS

The CD68 and CD34 counts were significantly lower in well-differentiated squamous cell carcinoma compared to poorly differentiated squamous cell carcinoma. Linear regression analysis revealed a positive correlation between the area percentage of CD68 immunoreactivity and the grade of the tumor (r = 0.776). Vice versa, a positive correlation also existed between the area percentage of CD34 immunoreactivity and the grade of the tumor (r = 0.690). Pearson correlation revealed a positive association between the TAMs and MVD (r = 0.680; P < .001).

CONCLUSIONS

There was an increased population of tumor-associated macrophages and tumor angiogenesis with the increasing grade of orofacial squamous cell carcinoma. (Oral Surg Oral Med Oral Pathol Oral Radiol YEAR;VOL:page range).

Exosomal noncoding RNAs: decoding their role in thyroid cancer progression

Exosomes, as pivotal entities within the tumor microenvironment, orchestrate intercellular communication through the transfer of diverse molecules, among which non-coding RNAs (ncRNAs) such as miRNAs, lncRNAs, and circRNAs play a crucial role. These ncRNAs, endowed with regulatory functions, are selectively incorporated into exosomes. Emerging evidence underscores the significance of exosomal ncRNAs in modulating key oncogenic processes in thyroid cancer (TC), including proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and immunoediting. The unique composition of exosomes shields their cargo from enzymatic and chemical degradation, ensuring their integrity and facilitating their specific expression in plasma. This positions exosomal ncRNAs as promising candidates for novel diagnostic and prognostic biomarkers in TC. Moreover, the potential of exosomes in the therapeutic landscape of TC is increasingly recognized. This review aims to elucidate the intricate relationship between exosomal ncRNAs and TC, fostering a deeper comprehension of their mechanistic involvement. By doing so, it endeavors to propel forward the exploration of exosomal ncRNAs in TC, ultimately paving the way for innovative diagnostic and therapeutic strategies predicated on exosomes and their ncRNA content.

The effects of tumor-derived supernatants (TDS) on cancer cell progression: A review and update on carcinogenesis and immunotherapy

Tumors can produce bioactive substances called tumor-derived supernatants (TDS) that modify the immune response in the host body. This can result in immunosuppressive effects that promote the growth and spread of cancer. During tumorigenesis, the exudation of these substances can disrupt the function of immune sentinels in the host and reinforce the support for cancer cell growth. Tumor cells produce cytokines, growth factors, and proteins, which contribute to the progression of the tumor and the formation of premetastatic niches. By understanding how cancer cells influence the host immune system through the secretion of these factors, we can gain new insights into cancer diagnosis and therapy.

IRX5's influence on macrophage polarization and outcome in papillary thyroid cancer

Background

With a rise in recent years, thyroid cancer (TC) is the most prevalent hormonal cancer worldwide. It is essential to investigate the inherent variability at the molecular level and the immune environment within tumors of various thyroid cancer subtypes in order to identify potential targets for therapy and provide precise treatment for patients with thyroid adenocarcinoma.

Methods

First, we analyzed the expression of IRX5 in pan-cancer and papillary thyroid carcinoma by bioinformatics methods and collected paired samples from our center for validation. Subsequently, we analyzed the significance of IRX5 on the prognosis and diagnosis of PTC. Next, we explored the possible mechanisms by which IRX5 affects the prognosis of thyroid cancer patients by GO/KEGG enrichment analysis, and further investigated the effect of IRX5 on immune infiltration of thyroid cancer. Ultimately, by conducting experiments on cells and animals, we were able to show how IRX5 impacts the aggressive characteristics of thyroid cancer cells and its influence on macrophages within the immune system of thyroid cancer.

Results

In 11 malignant tumors, including PTC, IRX5 is overexpressed and associated with a poor prognosis. IRX5 may affect the prognosis of PTC through embryonic organ development, ossification, mesenchyme development, etc. Increased IRX5 expression decreases the presence of cytotoxic and Th17 cells in papillary thyroid cancer. IRX5 was highly expressed in different PTC cell lines, such as K-1 and TPC-1. Silencing IRX5 effectively halted the growth and movement of PTC cells while also decreasing M2 polarization and enhancing M1 polarization in tumor-associated macrophages.

Conclusion

IRX5 could impact the outlook of individuals with PTC by stimulating the shift of macrophages to M2 in the immune surroundings of thyroid cancer growths, suggesting a potential new focus for treating thyroid cancer, particularly through immunotherapy.

Wnt signaling: Modulating tumor-associated macrophages and related immunotherapeutic insights

Wnt signaling pathways are highly conserved cascades that mediate multiple biological processes through canonical or noncanonical pathways, from embryonic development to tissue maintenance, but they also contribute to the pathogenesis of numerous cancers. Recent studies have revealed that Wnt signaling pathways critically control the interplay between cancer cells and tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) and potentially impact the efficacy of cancer immunotherapy. In this review, we summarize the evidence that Wnt signaling pathways boost the maturation and infiltration of macrophages for immune surveillance in the steady state but also polarize TAMs toward immunosuppressive M2-like phenotypes for immune escape in the TME. Both cancer cells and TAMs utilize Wnt signaling to transmit signals, and this interaction is crucial for the carcinogenesis and progression of common solid cancers, such as colorectal, gastric, hepatocellular, breast, thyroid, prostate, kidney, and lung cancers; osteosarcoma; and glioma. Specifically, compared with those in solid cancers, Wnt signaling pathways play a distinct role in the pathogenesis of leukemia. Efforts to develop Wnt-based drugs for cancer treatment are still ongoing, and some indeed enhance the anticancer immune response. We believe that the combination of Wnt signaling-based therapy with conventional or immune therapies is a promising therapeutic approach and can facilitate personalized treatment for most cancers.

HMGB1 in exosomes derived from gastric cancer cells induces M2-like macrophage polarization by inhibiting the NF-κB signaling pathway

Gastric cancer (GC) seriously threatens human health. High mobility group protein B1 (HMGB1) and M2-like macrophages are closely associated with core events about human cancers, such as invasion, and metastasis, and cancer microenvironment. This study mainly determined the regulatory effect of HMGB1 in GC cell-derived exosomes on M2-like macrophage polarization as well as the underlying mechanism. HMGB1 was found to be highly expressed in gastric tissue specimens, which might lead to the poor prognosis of GC. High levels of HMGB1 were also observed in the plasma of GC patients, indicating the possibility that it regulates the immune microenvironment via exosomes. Further study revealed and confirmed the regulatory effect of exosomes derived from GC cells with high HMGB1 level on inducing M2-like macrophage polarization. Mechanistically, by interacting with the transcription factor POU2F1, exosomal HMGB1 inhibited the transcriptional activity of p50, resulting in the inactivation of NF-κB signaling pathway and thereby inducing M2-like macrophage polarization. Moreover, instead of promoting the proliferation of GC cells, exosomes with high HMGB1 levels induced M2-like macrophage polarization and promoted GC progression. This study reveals a novel mechanism by which HMGB1 promotes GC progression, which may provide new insights for improving the efficacy of cancer immunotherapy.

Advances in the management of anaplastic thyroid carcinoma: transforming a life-threatening condition into a potentially treatable disease

Anaplastic thyroid cancer (ATC) is an infrequent thyroid tumor that usually occurs in elderly patients. There is often a history of previous differentiated thyroid cancer suggesting a biological progression. It is clinically characterized by a locally invasive cervical mass of rapid onset. Metastases are found at diagnosis in 50% of patients. Due to its adverse prognosis, a prompt diagnosis is crucial. In patients with unresectable or metastatic disease, multimodal therapy (chemotherapy and external beam radiotherapy) has yielded poor outcomes with 12-month overall survival of less than 20%. Recently, significant progress has been made in understanding the oncogenic pathways of ATC, leading to the identification of BRAF V600E mutations as the driver oncogene in nearly 40% of cases. The combination of the BRAF inhibitor dabrafenib (D) and MEK inhibitor trametinib (T) showed outstanding response rates in BRAF-mutated ATC and is now considered the standard of care in this setting. Recently, it was shown that neoadjuvant use of DT followed by surgery achieved 24-month overall survival rates of 80%. Although these approaches have changed the management of ATC, effective therapies are still needed for patients with BRAF wild-type ATC, and high-quality evidence is lacking for most aspects of this neoplasia. Additionally, in real-world settings, timely access to multidisciplinary care, molecular testing, and targeted therapies continues to be a challenge. Health policies are warranted to ensure specialized treatment for ATC.The expanding knowledge of ATC´s molecular biology, in addition to the ongoing clinical trials provides hope for the development of further therapeutic options.

Paclitaxel-induced inhibition of NSCLC invasion and migration via RBFOX3-mediated circIGF1R biogenesis

We previously reported that circIGF1R is significantly downregulated in non-small cell lung cancer (NSCLC) cells and tissues. It inhibits cancer cell invasion and migration, although the underlying molecular mechanisms remain elusive. The invasion and migration of NSCLC cells was analyzed by routine in vivo and in vitro functional assays. Fluorescent in situ hybridization, luciferase reporter assay, RNA pull-down assay and RNA immunoprecipitation (RIP) assay were performed to explore the molecular mechanisms. Mechanism of action of paclitaxel-induced RBFOX3-mediated inhibition of NSCLC invasion and migration was investigated through in vitro and in vivo experiments.Our study reveals that circIGF1R acts as a Competing Endogenous RNA (ceRNA) for miR-1270, thereby regulating Van-Gogh-like 2 (VANGL2) expression and subsequently inhibiting NSCLC cell invasion and migration via the Wnt pathway. We also found that RNA binding protein fox-1 homolog 3 (RBFOX3) enhances circIGF1R biogenesis by binding to IGF1R pre-mRNA, which in turn suppresses migration and invasion in NSCLC cells. Additionally, the chemotherapeutic drug paclitaxel was shown to impede NSCLC invasion and migration by inducing RBFOX3-mediated circIGF1R biogenesis.RBFOX3 inhibits the invasion and migration of NSCLC cells through the circIGF1R/ miR-1270/VANGL2 axis, circIGF1R has the potential to serve as a biomarker and therapeutic target for NSCLC.

Functional Roles of CD133: More than Stemness Associated Factor Regulated by the Microenvironment

CD133 protein has been one of the most used surface markers to select and identify cancer cells with stem-like features. However, its expression is not restricted to tumoral cells; it is also expressed in differentiated cells and stem/progenitor cells in various normal tissues. CD133 participates in several cellular processes, in part orchestrating signal transduction of essential pathways that frequently are dysregulated in cancer, such as PI3K/Akt signaling and the Wnt/β-catenin pathway. CD133 expression correlates with enhanced cell self-renewal, migration, invasion, and survival under stress conditions in cancer. Aside from the intrinsic cell mechanisms that regulate CD133 expression in each cellular type, extrinsic factors from the surrounding niche can also impact CD33 levels. The enhanced CD133 expression in cells can confer adaptive advantages by amplifying the activation of a specific signaling pathway in a context-dependent manner. In this review, we do not only describe the CD133 physiological functions known so far, but importantly, we analyze how the microenvironment changes impact the regulation of CD133 functions emphasizing its value as a marker of cell adaptability beyond a cancer-stem cell marker.

PLK4 inhibitor exhibits antitumor effect and synergizes sorafenib via arresting cell cycle and inactivating Wnt/β-catenin pathway in anaplastic thyroid cancer

The anti-tumor effect of polo-like kinase 4 (PLK4) inhibitor has been explored in several solid carcinomas, while its application in anaplastic thyroid cancer (ATC) remains scarce. Hence, the current study aimed to investigate the effect of PLK4 inhibitor on the malignant behaviors of ATC cell lines and its synergistic antitumor effect with sorafenib. C643 and 8305c cells were cultured in various concentrations of centrinone (PLK4 inhibitor) with or without sorafenib. Meanwhile, the cell viability, cell apoptosis, cell cycle and expressions of glycogen synthetase kinase beta (GSK3β), p-GSK3β, β-catenin were determined. PLK4 mRNA and protein expressions were higher in most ATC cell lines than the normal thyroid epithelial cell line (all P < .05). Centrinone decreased cell viability, induced cell apoptosis, arrested cell cycle at G2/M phase and inactivated Wnt/β-catenin signaling with dose-dependent manners in C643 and 8305c cells (all P < .05). Interestingly, centrinone plus sorafenib further improved antitumor effect (P < .05 at most concentrations), with the highest combination index at 5 nM centrinone plus 4 μM sorafenib in C643 cells, then 4 nM centrinone plus 4 μM sorafenib in C643 cells. Subsequently, centrinone plus sorafenib reduced cell viability, promoted cell apoptosis, facilitated cell cycle at G2/M phase and repressed Wnt/β-catenin signaling more effectively compared with centrinone or sorafenib monotherapy in C643 and 8305c cells (all P < .05). PLK4 inhibitor exhibits antitumor effect and synergizes sorafenib via arresting cell cycle and inactivating Wnt/β-catenin pathway in ATC.

Tumor-associated macrophages as a potential therapeutic target in thyroid cancers

Macrophages are important precursor cell types of the innate immune system and bridge adaptive immune responses through the antigen presentation system. Meanwhile, macrophages constitute substantial portion of the stromal cells in the tumor microenvironment (TME) (referred to as tumor-associated macrophages, or TAMs) and exhibit conflicting roles in the development, invasion, and metastasis of thyroid cancer (TC). Moreover, TAMs play a crucial role to the behavior of TC due to their high degree of infiltration and prognostic relevance. Generally, TAMs can be divided into two subgroups; M1-like TAMs are capable of directly kill tumor cells, and recruiting and activating other immune cells in the early stages of cancer. However, due to changes in the TME, M2-like TAMs gradually increase and promote tumor progression. This review aims to discuss the impact of TAMs on TC, including their role in tumor promotion, gene mutation, and other factors related to the polarization of TAMs. Finally, we will explore the M2-like TAM-centered therapeutic strategies, including chemotherapy, clinical trials, and combinatorial immunotherapy.

New Insights into Immune Cells and Immunotherapy for Thyroid Cancer

Thyroid cancer (TC) is the most common endocrine malignancy worldwide, and the incidence of TC has gradually increased in recent decades. Differentiated thyroid cancer (DTC) is the most common subtype and has a good prognosis. However, advanced DTC patients with recurrence, metastasis and iodine refractoriness, as well as more aggressive subtypes such as poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC), still pose a great challenge for clinical management. Therefore, it is necessary to continue to explore the inherent molecular heterogeneity of different TC subtypes and the global landscape of the tumor immune microenvironment (TIME) to find new potential therapeutic targets. Immunotherapy is a promising therapeutic strategy that can be used alone or in combination with drugs targeting tumor-driven genes. This article focuses on the genomic characteristics, tumor-associated immune cell infiltration and immune checkpoint expression of different subtypes of TC patients to provide guidance for immunotherapy.

Crosstalk between Thyroid Carcinoma and Tumor-Correlated Immune Cells in the Tumor Microenvironment

Thyroid cancer (TC) is the most common malignancy in the endocrine system. Although most TC can achieve a desirable prognosis, some refractory thyroid carcinomas, including radioiodine-refractory differentiated thyroid cancer, as well as anaplastic thyroid carcinoma, face a myriad of difficulties in clinical treatment. These types of tumors contribute to the majority of TC deaths due to limited initial therapy, recurrence, and metastasis of the tumor and tumor resistance to current clinically targeted drugs, which ultimately lead to treatment failure. At present, a growing number of studies have demonstrated crosstalk between TC and tumor-associated immune cells, which affects tumor deterioration and metastasis through distinct signal transduction or receptor activation. Current immunotherapy focuses primarily on cutting off the interaction between tumor cells and immune cells. Since the advent of immunotherapy, scholars have discovered targets for TC immunotherapy, which also provides new strategies for TC treatment. This review methodically and intensively summarizes the current understanding and mechanism of the crosstalk between distinct types of TC and immune cells, as well as potential immunotherapy strategies and clinical research results in the area of the tumor immune microenvironment. We aim to explore the current research advances to formulate better individualized treatment strategies for TC patients and to provide clues and references for the study of potential immune checkpoints and the development of immunotherapy technologies.

Cells of the tumor microenvironment speak the Wnt language

Wnt signaling plays numerous functions in cancer, from primary transformation and tumor growth to metastasis. In addition to these cancer cell-intrinsic functions, Wnt signaling emerges to critically control cross-communication among cancer cells and the tumor microenvironment (TME). Here, we summarize the evidence that not only multiple cancer cell types, but also cells constituting the TME 'speak the Wnt language'. Fibroblasts, macrophages, endothelia, and lymphocytes all use the Wnt language to convey messages to and from cancer cells and among themselves; these messages are important for tumor progression and fate. Decoding this language will advance our understanding of tumor biology and unveil novel therapeutic avenues.

Organoids of patient-derived medullary thyroid carcinoma: The first milestone towards a new in vitro model in dogs

Organoid cultures could constitute a valuable in vitro model to explore new treatments for canine (c) medullary thyroid carcinoma (MTC). The study's objectives were to establish and characterize 3D organoid cultures of cMTC using histology and immunohistochemistry (IHC) and to evaluate the effect of antitumor drugs on organoids' viability. Five cMTC tissue samples were used to develop organoid cultures of which one organoid line, named cMTC N°2, could be passaged for an extended period. This cMTC N°2 organoid line was further compared to the primary tumour regarding morphology and IHC expression of thyroid transcription factor-1 (TTF-1), thyroglobulin, calcitonin, synaptophysin, vimentin, Ki-67, cyclooxygenase-2 (COX-2), P-glycoprotein and vascular endothelial growth factor (VEGF). Quality control of the cMTC N°2 organoid line was achieved by a single nucleotide polymorphism (SNP) array of the organoids, primary tumour and healthy blood cells of the same dog. The effect of carboplatin, meloxicam and toceranib phosphate (TOC) on cMTC N°2 organoids' viability was evaluated. The cMTC N°2 organoid line was cultured for 94 days and showed similar histological features with the primary tumour. Immunolabelling for TTF-1, thyroglobulin, calcitonin and VEGF was similar between the primary tumour and cMTC N°2 organoids. Compared to the primary tumour, organoids showed higher immunolabelling for vimentin and Ki-67, and lower immunolabelling for synaptophysin, COX-2 and P-glycoprotein. The SNP genotype was similar for each chromosome between healthy blood cells, primary tumour and cMTC N°2 organoids. Carboplatin, meloxicam and TOC had no effect on cMTC N°2 organoid cell viability within achievable in vivo concentration range. In conclusion, the cMTC N°2 organoid line is a promising first milestone towards an established in vitro organoid model to explore pathophysiology and new treatment modalities in cMTC.

Norepinephrine inhibits CD8+ T-cell infiltration and function, inducing anti-PD-1 mAb resistance in lung adenocarcinoma

BACKGROUND

Mental stress-induced neurotransmitters can affect the immune system in various ways. Therefore, a better understanding of the role of neurotransmitters in the tumour immune microenvironment is expected to promote the development of novel anti-tumour therapies.

METHODS

In this study, we analysed the plasma levels of neurotransmitters in anti-programmed cell death protein 1 (PD-1) monoclonal antibody (mAb)-resistance patients and sensitive patients, to identify significantly different neurotransmitters. Subsequently, animal experiments and experiments in vitro were used to reveal the specific mechanism of norepinephrine's (NE) effect on immunotherapy.

RESULTS

The plasma NE levels were higher in anti-PD-1 mAb-resistance patients, which may be the main cause of anti-PD-1 mAb resistance. Then, from the perspective of the immunosuppressive microenvironment to explore the specific mechanism of NE-induced anti-PD-1 mAb resistance, we found that NE can affect the secretion of C-X-C Motif Chemokine Ligand 9 (CXCL9) and adenosine (ADO) in tumour cells, thereby inhibiting chemotaxis and function of CD8⁺ T cells. Notably, the WNT7A/β-catenin signalling pathway plays a crucial role in this progression.

CONCLUSION

NE can affect the secretion of CXCL9 and ADO in tumour cells, thereby inhibiting chemotaxis and the function of CD8⁺ T cells and inducing anti-PD-1 mAb resistance in lung adenocarcinoma (LUAD).

Wnt Signaling in the Phenotype and Function of Tumor-Associated Macrophages

Tumor-associated macrophages (TAM) play an important role in supporting tumor growth and suppressing antitumor immune responses, and TAM infiltration has been associated with poor patient prognosis in various cancers. TAMs can be classified as pro-inflammatory, M1-like, or anti-inflammatory, M2-like. While multiple factors within the tumor microenvironment affect the recruitment, polarization, and functions of TAMs, accumulating evidence suggests that Wnt signaling represents an important, targetable driver of an immunosuppressive, M2-like TAM phenotype. TAM production of Wnt ligands mediates TAM-tumor cross-talk to support cancer cell proliferation, invasion, and metastasis. Targeting TAM polarization and the protumorigenic functions of TAMs through inhibitors of Wnt signaling may prove a beneficial treatment strategy in cancers where macrophages are prevalent in the microenvironment.

Pathobiology and Therapeutic Relevance of GSK-3 in Chronic Hematological Malignancies

Glycogen synthase kinase-3 (GSK-3) is an evolutionarily conserved, ubiquitously expressed, multifunctional serine/threonine protein kinase involved in the regulation of a variety of physiological processes. GSK-3 comprises two isoforms (α and β) which were originally discovered in 1980 as enzymes involved in glucose metabolism via inhibitory phosphorylation of glycogen synthase. Differently from other proteins kinases, GSK-3 isoforms are constitutively active in resting cells, and their modulation mainly involves inhibition through upstream regulatory networks. In the early 1990s, GSK-3 isoforms were implicated as key players in cancer cell pathobiology. Active GSK-3 facilitates the destruction of multiple oncogenic proteins which include β-catenin and Master regulator of cell cycle entry and proliferative metabolism (c-Myc). Therefore, GSK-3 was initially considered to be a tumor suppressor. Consistently, GSK-3 is often inactivated in cancer cells through dysregulated upstream signaling pathways. However, over the past 10–15 years, a growing number of studies highlighted that in some cancer settings GSK-3 isoforms inhibit tumor suppressing pathways and therefore act as tumor promoters. In this article, we will discuss the multiple and often enigmatic roles played by GSK-3 isoforms in some chronic hematological malignancies (chronic myelogenous leukemia, chronic lymphocytic leukemia, multiple myeloma, and B-cell non-Hodgkin’s lymphomas) which are among the most common blood cancer cell types. We will also summarize possible novel strategies targeting GSK-3 for innovative therapies of these disorders.

Functional role of the Frizzled linker domain in the Wnt signaling pathway

The Wnt signaling pathway plays a critical role in the developmental and physiological processes of metazoans. We previously reported that the Frizzled4 (FZD4) linker domain plays an important role in Norrin binding and signaling. However, the question remains whether the FZD linker contributes to Wnt signaling in general. Here, we show that the FZD linker is involved in Wnt binding and affects downstream Wnt signaling. A FZD4 chimera, in which the linker was swapped with that of the non-canonical receptor FZD6, impairs the binding with WNT3A and suppresses the recruitment of LRP6 and Disheveled, resulting in reduced canonical signaling. A similar effect was observed for non-canonical signaling. A FZD6 chimera containing the FZD1 linker showed reduced WNT5A binding and impaired signaling in ERK, JNK, and AKT mediated pathways. Altogether, our results suggest that the FZD linker plays an important role in specific Wnt binding and intracellular Wnt signaling.

Wnt3a but not CDX-2 expression is associated with differentiated thyroid cancer

OBJECTIVE

Thyroid neoplasm incidence has increased worldwide, mostly due to the advancements in medical imaging and screening rates. The aberrant Wnt/β-catenin pathway has been identified as a key mechanism, and it has also been related to the metastatic activity of differentiated thyroid cancer. We aimed to verify the difference in the expression of Wnt3a, a canonical activator of the β-catenin signaling, and CDX-2, a transcription factor upregulated by Wnt/β-catenin pathway, in multinodular goiter and differentiated thyroid cancer and to determine their prognostic value.

METHODS

We included 194 thyroid tissue surgical specimen and their clinicopathological data: study group (differentiated thyroid cancer, n=154) and control group (multinodular goiter, n=40). Immunohistochemistry (IHC) was performed on formalin-fixed, paraffin-embedded tissue by the primary antibodies Wnt3a and CDX-2.

RESULTS

High Wnt3a expression was significantly associated with differentiated thyroid cancer (p=0.031). CDX-2 was negative in all differentiated thyroid cancer cases (100%) and also in multinodular goiter. Wnt3a expression was significantly associated with tumors ≤20 mm (p=0.044) and with the absence of capsule invasion (p=0.031). The multivariate analyses suggested that older age (≥55), independent of capsular invasion and tumor size, was an independent prognostic factor for Wnt3a expression (p=0.058).

CONCLUSIONS

Wnt3a expression but not CDX-2 is correlated with differentiated thyroid cancer samples in comparison to multinodular goiter. Although its prognostic value was limited to tumor size and capsule invasion, a combined model in a panel of immune markers can add accuracy in the classification of challenging thyroid follicular-derived lesions.

Roles and new Insights of Macrophages in the Tumor Microenvironment of Thyroid Cancer

Although most thyroid cancers have a good and predictable prognosis, the anaplastic, medullary, and refractory thyroid cancers still prone to recurrence and metastasis, resulting in poor prognosis. Although a number of newly developed targeted therapies have begun to be indicated for the above types of thyroid cancer in recent years, their ability to improve overall survival remain hindered by low efficacy. As the largest component of immune cells in tumor microenvironment, tumor-associated macrophages play a key role in the invasion and metastasis of thyroid cancer. There is much evidence that the immune system, tumor microenvironment and cancer stem cell interactions may revolutionize traditional therapeutic directions. Tumor-associated macrophages have been extensively studied in a variety of tumors, however, research on the relationship between thyroid cancer and macrophages is still insufficient. In this review, we summarize the functions of tumor-associated macrophages in different types of thyroid cancer, their cytokines or chemokines effect on thyroid cancer and the mechanisms that promote tumor proliferation and migration. In addition, we discuss the mechanisms by which tumor-associated macrophages maintain the stemness of thyroid cancer and potential strategies for targeting tumor-associated macrophages to treat thyroid cancer.

LncRNA RMRP accelerates autophagy-mediated neurons apoptosis through miR-3142/TRIB3 signaling axis in Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a major neurodegenerative disorder. The functions of lncRNA RMRP have been characterized mainly in various human cancers. However, the functional network of RMRP in AD progression remains unknown.

METHODS

Human serum samples, AD transgenic (Tg) mice as well as SH-SY5Y cells were used in this study. The RNA expression patterns of RMRP, miR-3142 and TRIB3 were assessed by quantitative real-time PCR (qRT-PCR). Levels of apoptosis- or autophagy-associated biomarkers and TRIB3 level were evaluated using immunohistochemistry (IHC), western blotting or immunofluorescence assays, respectively. Bioinformatics methods and luciferase assays were used to predict and validate the interactions among RMRP, miR-3142, and TRIB3. Flow cytometry, TUNEL staining and EdU assays were used to examine the apoptosis and proliferation of neurons, respectively.

RESULTS

The elevated RMRP and TRIB3 expressions and activation of autophagy were observed in AD. Knockdown of RMRP restrained neuronal apoptosis and autophagy activation in vitro and in vivo. Interestingly, TRIB3 overexpression reversed the biological effects of RMRP silencing on Aβ_1-42-induced cell apoptosis and autophagy. Further mechanistic analysis showed RMRP acted as a sponge of miR-3142 to elevate TRIB3 level.

CONCLUSION

These data illustrated that knockdown of RMRP inhibited autophagy and apoptosis via regulating miR-3142/TRIB3 axis in AD, suggesting that inhibition of RMRP maybe a therapeutic strategy for AD.

Metformin and Cancer Hallmarks: Molecular Mechanisms in Thyroid, Prostate and Head and Neck Cancer Models

Metformin is the most used drug for type 2 diabetes (T2DM). Its antitumor activity has been described by clinical studies showing reduced risk of cancer development in T2DM patients, as well as management of T2DM compared with those receiving other glucose-lowering drugs. Metformin has a plethora of molecular actions in cancer cells. This review focused on in vitro data on the action mechanisms of metformin on thyroid, prostate and head and neck cancer. AMPK activation regulating specific downstream targets is a constant antineoplastic activity in different types of cancer; however, AMPK-independent mechanisms are also relevant. In vitro evidence makes it clear that depending on the type of tumor, metformin has different actions; its effects may be modulated by different cell conditions (for instance, presence of HPV infection), or it may regulate tissue-specific factors, such as the Na+/I- symporter (NIS) and androgen receptors. The hallmarks of cancer are a set of functional features acquired by the cell during malignant development. In vitro studies show that metformin regulates almost all the hallmarks of cancer. Interestingly, metformin is one of these therapeutic agents with the potential to synergize with other chemotherapeutic agents, with low cost, low side effects and high positive consequences. Some questions are still challenging: Are metformin in vitro data able to translate from bench to bedside? Does metformin affect drug resistance? Can metformin be used as a generic anticancer drug for all types of tumors? Which are the specific actions of metformin on the peculiarities of each type of cancer? Several clinical trials are in progress or have been concluded for repurposing metformin as an anticancer drug. The continuous efforts in the field and future in vitro studies will be essential to corroborate clinical trials results and to elucidate the raised questions.

Anaplastic Thyroid Carcinoma: An Update

Anaplastic thyroid carcinoma (ATC) is a rare and undifferentiated form of thyroid cancer. Its prognosis is poor: the median overall survival (OS) of patients varies from 4 to 10 months after diagnosis. However, a doubling of the OS time may be possible owing to a more systematic use of molecular tests for targeted therapies and integration of fast-track dedicated care pathways for these patients in tertiary centers. The diagnostic confirmation, if needed, requires an urgent biopsy reread by an expert pathologist with additional immunohistochemical and molecular analyses. Therapeutic management, defined in multidisciplinary meetings, respecting the patient's choice, must start within days following diagnosis. For localized disease diagnosed after primary surgical treatment, adjuvant chemo-radiotherapy is recommended. In the event of locally advanced or metastatic disease, the prognosis is very poor. Treatment should then involve chemotherapy or targeted therapy and decompressive cervical radiotherapy. Here we will review current knowledge on ATC and provide perspectives to improve the management of this deadly disease.

Role of Suprabasin in the Dedifferentiation of Follicular Epithelial Cell-Derived Thyroid Cancer and Identification of Related Immune Markers

Background: Aberrant regulation of suprabasin (SBSN) is associated with the development of cancer and immune disorders. SBSN influences tumor cell migration, proliferation, angiogenesis, and immune resistance. In this study, we investigated the potential correlation between SBSN expression and immune infiltration in thyroid cancer.

Methods: The expression of SBSN in 80 papillary thyroid carcinoma (PTC) specimens was determined using quantitative reverse-transcription polymerase chain reaction, western blotting, and immunohistochemical staining. The expression of SBSN in 9 cases of poorly differentiated thyroid carcinoma (PDTC) and 18 cases of anaplastic thyroid carcinoma (ATC) was evaluated by immunohistochemical staining. Comprehensive bioinformatics analysis of SBSN expression was performed using The Cancer Genome Atlas and Gene Expression Omnibus datasets, and the relationship of SBSN expression with M2 macrophages and T regulatory cells (Tregs) in ATC and PTC was verified by immunohistochemical staining.

Results: Compared with those in adjacent normal tissues, the expression levels of SBSN mRNA and protein were significantly higher in PTC tissues. SBSN expression level was correlated with that of cervical lymph node metastasis in PTC patients. Immunohistochemical staining results showed statistically significant differences among high-positive expression rates of SBSN in PTC, PDTC, and ATC. Functional enrichment analysis showed that SBSN expression was associated with pathways related to cancer, cell signaling, and immune response. Furthermore, analysis of the tumor microenvironment (using CIBERSORT-ABS and xCell algorithms) showed that SBSN expression affected immune cell infiltration and the cancer immunity cycle, and immunohistochemistry confirmed a significant increase in M2 macrophage and Treg infiltration in tumor tissues with high-positive SBSN expression.

Conclusion: These findings reveal that SBSN may be involved in thyroid carcinogenesis, tumor dedifferentiation progression, and immunosuppression as an important regulator of tumor immune cell infiltration.

E-cadherin on epithelial-mesenchymal transition in thyroid cancer

Thyroid carcinoma is a common malignant tumor of endocrine system and head and neck. Recurrence, metastasis and high malignant expression after routine treatment are serious clinical problems, so it is of great significance to explore its mechanism and find action targets. Epithelial-mesenchymal transition (EMT) is associated with tumor malignancy and invasion. One key change in tumour EMT is low expression of E-cadherin. Therefore, this article reviews the expression of E-cadherin in thyroid cancers (TC), discuss the potential mechanisms involved, and outline opportunities to exploit E-cadherin on regulating the occurrence of EMT as a critical factor in cancer therapeutics.

Wnt/β-catenin signaling in cancers and targeted therapies

Wnt/β-catenin signaling has been broadly implicated in human cancers and experimental cancer models of animals. Aberrant activation of Wnt/β-catenin signaling is tightly linked with the increment of prevalence, advancement of malignant progression, development of poor prognostics, and even ascendence of the cancer-associated mortality. Early experimental investigations have proposed the theoretical potential that efficient repression of this signaling might provide promising therapeutic choices in managing various types of cancers. Up to date, many therapies targeting Wnt/β-catenin signaling in cancers have been developed, which is assumed to endow clinicians with new opportunities of developing more satisfactory and precise remedies for cancer patients with aberrant Wnt/β-catenin signaling. However, current facts indicate that the clinical translations of Wnt/β-catenin signaling-dependent targeted therapies have faced un-neglectable crises and challenges. Therefore, in this study, we systematically reviewed the most updated knowledge of Wnt/β-catenin signaling in cancers and relatively targeted therapies to generate a clearer and more accurate awareness of both the developmental stage and underlying limitations of Wnt/β-catenin-targeted therapies in cancers. Insights of this study will help readers better understand the roles of Wnt/β-catenin signaling in cancers and provide insights to acknowledge the current opportunities and challenges of targeting this signaling in cancers.

Cancer stem cells, epithelial-mesenchymal transition, ATP and their roles in drug resistance in cancer

The cancer stem cell (CSC) state and epithelial-mesenchymal transition (EMT) activation are tightly interconnected. Cancer cells that acquire the EMT/CSC phenotype are equipped with adaptive metabolic changes to maintain low reactive oxygen species levels and stemness, enhanced drug transporters, anti-apoptotic machinery and DNA repair system. Factors present in the tumor microenvironment such as hypoxia and the communication with non-cancer stromal cells also promote cancer cells to enter the EMT/CSC state and display related resistance. ATP, particularly the high levels of intratumoral extracellular ATP functioning through both signaling pathways and ATP internalization, induces and regulates EMT and CSC. The three of them work together to enhance drug resistance. New findings in each of these factors will help us explore deeper into mechanisms of drug resistance and suggest new resistance-associated markers and therapeutic targets.

Alteration of Macrophage Infiltrating Compartment: A Novel View on Oral Carcinogenesis

BACKGROUND

The mortality of oral squamous cell carcinoma (OSCC) has remained high for decades; therefore, methods for early detection of OSCC are warranted. However, in the oral cavity, various mucosal diseases may be encountered, including reactive lesions and oral potentially malignant disorders, and it is difficult to differentiate OSCC from these lesions based on both clinical and histopathological findings. It is well known that chronic inflammation contributes to oral cancer development. Macrophages are among the most common inflammatory cells in cancer stromal tissue and have various roles in cancer aggressiveness. Although the roles of macrophages in cancer development have attracted attention, only a few studies have linked macrophages to carcinogenesis, particularly, oral precancerous lesions.

SUMMARY

This review article consists of 3 parts: first, we summarize current knowledge on macrophages in human various epithelial precancerous lesions, excluding the oral cavity, to show the importance and gaps in knowledge regarding macrophages in carcinogenesis; second, we review published data related to the role of macrophages in oral carcinogenesis; finally, we present a novel view on oral carcinogenesis, focusing on crosstalk between epithelial cells and macrophages. Key Messages: The biological features of macrophages in oral carcinogenesis differ drastically depending on the anatomical compartment that they infiltrate. Focusing on the alteration of macrophage infiltrating compartment may serve as a useful novel approach for studying the role of the macrophages in oral carcinogenesis and for gaining further insight into cancer prevention and early detection.

IL-35 promotes EMT through STAT3 activation and induces MET by promoting M2 macrophage polarization in HCC

The tumor microenvironment and interplay with cancer cells could promote tumor growth and metastasis. Here we report that polarization state of macrophages could affect epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET). IL-35 level secreted by M1 macrophage was significantly higher than M2 macrophage and it facilitated EMT process through activation of STAT3 in hepatocellular carcinoma cells. Interestingly, IL-35 could not directly promote MET, but it could indirectly induce MET of HCC cells through M2 macrophage polarization. These results indicated the level of IL-35 in tumor microenvironment may fluctuate at different stages of oncogenesis to regulate epithelial plasticity of HCC and provide potential therapeutic targets for tumor metastasis.