IL6/JAK1/STAT3 Signaling Blockade in Endometrial Cancer Affects the ALDHhi/CD126+ Stem-like Component and Reduces Tumor Burden

Potential Benefits of Adding Alendronate, Celecoxib, Itraconazole, Ramelteon, and Simvastatin to Endometrial Cancer Treatment: The EC5 Regimen

Metastatic endometrial cancer continues to be a common cause of death as of 2024, even after maximal use of all currently available standard treatments. To address this problem of metastatic cancer generally in 2025, the drug repurposing movement within oncology identifies medicines in common general medical use that have clinical or preclinical experimental data indicating that they interfere with or inhibit a specific growth driving element identified in a given cancer. The drug repurposing movement within oncology also uses data from large scale in vitro screens of thousands of drugs, looking for simple empirical growth inhibition in a given cancer type. This paper outlines the data showing that five drugs from general medical practice meet these evidence criteria for inhibition of endometrial cancer growth, the EC5 regimen. The EC5 regimen uses the osteoporosis treatment drug, alendronate; the analgesic drug, celecoxib; the antifungal drug, itraconazole; the sleep aid, ramelteon; and the cholesterol lowering drug, simvastatin. Side effects seen with these drugs are usually minimal and easily tolerated by patients.

Mitochondrial dysfunction route as a possible biomarker and therapy target for human cancer

Mitochondria are vital organelles found within living cells and have signalling, biosynthetic, and bioenergetic functions. Mitochondria play a crucial role in metabolic reprogramming, which is a characteristic of cancer cells and allows them to ensure a steady supply of proteins, nucleotides, and lipids to enable rapid proliferation and development. Their dysregulated activities have been associated with the growth and metastasis of different kinds of human cancer, particularly ovarian carcinoma. In this review, we briefly demonstrated the modified mitochondrial function in cancer, including mutations in mitochondrial DNA (mtDNA), reactive oxygen species (ROS) production, dynamics, apoptosis of cells, autophagy, and calcium excess to maintain cancer genesis, progression, and metastasis. Furthermore, the mitochondrial dysfunction pathway for some genomic, proteomic, and metabolomics modifications in ovarian cancer has been studied. Additionally, ovarian cancer has been linked to targeted therapies and biomarkers found through various alteration processes underlying mitochondrial dysfunction, notably targeting (ROS), metabolites, rewind metabolic pathways, and chemo-resistant ovarian carcinoma cells.

Insights into IL-6/JAK/STAT3 signaling in the tumor microenvironment: Implications for cancer therapy

The IL-6/JAK/STAT3 signaling pathway is a key regulator of tumor progression, immune evasion, and therapy resistance in various cancers. Frequently dysregulated in malignancies, this pathway drives cancer cell growth, survival, angiogenesis, and metastasis by altering the tumor microenvironment (TME). IL-6 activates JAK kinases and STAT3 through its receptor complex, leading to the transcription of oncogenic genes and fostering an immunosuppressive TME. This environment recruits tumor-associated macrophages (TAMs), cancer-associated fibroblasts (CAFs), and regulatory T cells (Tregs), collectively supporting immune evasion and tumor growth. IL-6/JAK/STAT3 axis also contributes to metabolic reprogramming, such as enhanced glycolysis and glutathione metabolism, helping cancer cells adapt to environmental stresses. Therapeutic targeting of this pathway has gained significant interest. Strategies include monoclonal antibodies against IL-6 or its receptor (e.g., Tocilizumab, Siltuximab), JAK inhibitors (e.g., Ruxolitinib), and STAT3-specific inhibitors (e.g., Napabucasin), which have exhibited promise in preclinical and initial clinical studies. These inhibitors can suppress tumor growth, reverse immune suppression, and enhance the efficacy of immunotherapies like immune checkpoint inhibitors. Combination therapies that integrate IL-6 pathway inhibitors with conventional treatments are particularly promising, addressing resistance mechanisms and improving patient outcomes. Advances in biomarker-driven patient selection, RNA-based therapies, and isoform-specific inhibitors pave the way for more precise interventions. This review delves into the diverse roles of IL-6/JAK/STAT3 signaling in cancer progression, therapeutic strategies targeting this pathway, and the potential for integrating these approaches into personalized medicine to enhance treatment outcomes.

Methods for Overcoming Chemoresistance in Head and Neck Squamous Cell Carcinoma: Keeping the Focus on Cancer Stem Cells, a Systematic Review

According to the "cancer stem cell" (CSCs) theory, tumors are a diverse and expanding group of malignant cells that originate from a small number of CSCs. Despite treatment, these cells can still become active and proliferate, which can result in distant metastasis and local recurrences. A new paradigm in cancer treatment involves targeting both CSCs and the cancer cells in a tumor. This review aims to examine the literature on methods published to overcome chemoresistance due to the presence of CSCs in head and neck cancers. The review was registered with PROSPERO (ID# CRD42024512809). After Pub Med, Scopus, and WoS database searches, 31 relevant articles on oral squamous cell carcinoma (OSCC) were selected. Compounds that increased chemosensitivity by targeting CSCs in head and neck squamous cell carcinoma (HNSCC) were divided into (1) natural products, (2) adjuvant molecules to traditional chemotherapy, and (3) CSCs targeting patient-specific fresh biopsies for functional precision medicine.

Influence of Aldehyde Dehydrogenase Inhibition on Stemness of Endometrial Cancer Stem Cells

Endometrial cancer is one of the most common gynaecological malignancies. Although often diagnosed at an early stage, there is a subset of patients with recurrent and metastatic disease for whom current treatments are not effective. Cancer stem cells (CSCs) play a pivotal role in triggering tumorigenesis, disease progression, recurrence, and metastasis, as high aldehyde dehydrogenase (ALDH) activity is associated with invasiveness and chemotherapy resistance. Therefore, this study aimed to evaluate the effects of ALDH inhibition in endometrial CSCs. ECC-1 and RL95-2 cells were submitted to a sphere-forming protocol to obtain endometrial CSCs. ALDH inhibition was evaluated through ALDH activity and expression, sphere-forming capacity, self-renewal, projection area, and CD133, CD44, CD24, and P53 expression. A mass spectrometry-based proteomic study was performed to determine the proteomic profile of endometrial cancer cells upon N,N-diethylaminobenzaldehyde (DEAB). DEAB reduced ALDH activity and expression, along with a significant decrease in sphere-forming capacity and projection area, with increased CD133 expression. Additionally, DEAB modulated P53 expression. Endometrial cancer cells display a distinct proteomic profile upon DEAB, sharing 75 up-regulated and 30 down-regulated proteins. In conclusion, DEAB inhibits ALDH activity and expression, influencing endometrial CSC phenotype. Furthermore, ALDH18A1, SdhA, and UBAP2L should be explored as novel molecular targets for endometrial cancer.

Cancer stem cells and their niche in cancer progression and therapy

High recurrence and metastasis rates and poor prognoses are the major challenges of current cancer therapy. Mounting evidence suggests that cancer stem cells (CSCs) play an important role in cancer development, chemoradiotherapy resistance, recurrence, and metastasis. Therefore, targeted CSC therapy has become a new strategy for solving the problems of cancer metastasis and recurrence. Since the properties of CSCs are regulated by the specific tumour microenvironment, the so-called CSC niche, which targets crosstalk between CSCs and their niches, is vital in our pursuit of new therapeutic opportunities to prevent cancer from recurring. In this review, we aim to highlight the factors within the CSC niche that have important roles in regulating CSC properties, including the extracellular matrix (ECM), stromal cells (e.g., associated macrophages (TAMs), cancer-associated fibroblasts (CAFs), and mesenchymal stem cells (MSCs)), and physiological changes (e.g., inflammation, hypoxia, and angiogenesis). We also discuss recent progress regarding therapies targeting CSCs and their niche to elucidate developments of more effective therapeutic strategies to eliminate cancer.

Oxidative stress regulation and related metabolic pathways in epithelial-mesenchymal transition of breast cancer stem cells

Epithelial-mesenchymal transition (EMT) is a cell remodeling process in which epithelial cells undergo a reversible phenotype switch via the loss of adhesion capacity and acquisition of mesenchymal characteristics. In other words, EMT activation can increase invasiveness and metastatic properties, and prevent the sensitivity of tumor cells to chemotherapeutics, as mesenchymal cells have a higher resistance to chemotherapy and immunotherapy. EMT is orchestrated by a complex and multifactorial network, often linked to episodic, transient, or partial events. A variety of factors have been implicated in EMT development. Based on this concept, multiple metabolic pathways and master transcription factors, such as Snail, Twist, and ZEB, can drive the EMT. Emerging evidence suggests that oxidative stress plays a significant role in EMT induction. One emerging theory is that reducing mitochondrial-derived reactive oxygen species production may contribute to EMT development. This review describes how metabolic pathways and transcription factors are linked to EMT induction and addresses the involvement of signaling pathways.

Endometrial cell‑derived exosomes facilitate the development of adenomyosis via the IL‑6/JAK2/STAT3 pathway

Interleukin (IL)-6 upregulation is involved in the pathogenesis of adenomyosis, but the underlying mechanism remains to be elucidated. Exosomes mediate intercellular communication, therefore the present study investigated whether endometrial cell-derived exosomes mediated the crosstalk between the endometrium and the myometrium via IL-6 signaling. Primary adenomyotic myometrial (AM) cells and eutopic endometrial cells were isolated from patients with adenomyosis. Exosomes were obtained from endometrial cells and incubated with AM cells in the presence or absence of tocilizumab (an IL-6 inhibitor). MTT, flow cytometry and wound-healing assays were performed to examine AM cell proliferation, apoptosis, cell cycle distribution and migration. Western blotting and reverse transcription-quantitative PCR were conducted to determine the expression of the IL-6/Janus kinase 2 (JAK2)/STAT3 pathway proteins. Incubation with endometrial cell exosomes suppressed cell apoptosis of AM cells compared with controls, accompanied by increases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell exosomes promoted cell proliferation, increased the percentage of S-phase cells and enhanced the migration of AM cells. These effects were completely reversed by tocilizumab, along with substantial decreases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell-derived exosomes promote cell proliferation, migration and cell cycle transition of AM cells through IL-6/JAK2/STAT3 activation, facilitating the development of adenomyosis by mediating the crosstalk between the endometrium and the myometrium, and IL-6 targeted therapy could be a complementary approach against adenomyosis.

The tumor multi-omic landscape of endometrial cancers developed on a germline genetic background of adiposity

High body mass index (BMI) is a causal risk factor for endometrial cancer but the tumor molecular mechanisms affected by adiposity and their therapeutic relevance remain poorly understood. Here we characterize the tumor multi-omic landscape of endometrial cancers that have developed on a background of lifelong germline genetic exposure to elevated BMI. We built a polygenic score (PGS) for BMI in women using data on independent, genome-wide significant variants associated with adult BMI in 434,794 women. We performed germline (blood) genotype quality control and imputation on data from 354 endometrial cancer cases from The Cancer Genome Atlas (TCGA). We assigned each case in this TCGA cohort their genetically predicted life-course BMI based on the BMI PGS. Multivariable generalized linear models adjusted for age, stage, microsatellite status and genetic principal components were used to test for associations between the BMI germline PGS and endometrial cancer tumor genome-wide genomic, transcriptomic, proteomic, epigenomic and immune traits in TCGA. High BMI germline PGS was associated with (i) upregulated tumor gene expression in the IL6-JAK-STAT3 pathway (FDR=4.2×10-7); (ii) increased estimated intra-tumor activated mast cell infiltration (FDR=0.008); (iii) increased single base substitution (SBS) mutational signatures 1 (FDR=0.03) and 5 (FDR=0.09) and decreased SBS13 (FDR=0.09), implicating age-related and APOBEC mutagenesis, respectively; and (iv) decreased tumor EGFR protein expression (FDR=0.07). Alterations in IL6-JAK-STAT3 signaling gene and EGFR protein expression were, in turn, significantly associated with both overall survival and progression-free interval. Thus, we integrated germline and somatic data using a novel study design to identify associations between genetically predicted lifelong exposure to higher BMI and potentially actionable endometrial cancer tumor molecular features. These associations inform our understanding of how high BMI may influence the development and progression of this cancer, impacting endometrial tumor biology and clinical outcomes.

Molecular Mechanisms of Tumor Cell Stemness Modulation during Formation of Spheroids

Cancer stem cells (CSCs), their properties and interaction with microenvironment are of interest in modern medicine and biology. There are many studies on the emergence of CSCs and their involvement in tumor pathogenesis. The most important property inherent to CSCs is their stemness. Stemness combines ability of the cell to maintain its pluripotency, give rise to differentiated cells, and interact with environment to maintain a balance between dormancy, proliferation, and regeneration. While adult stem cells exhibit these properties by participating in tissue homeostasis, CSCs behave as their malignant equivalents. High tumor resistance to therapy, ability to differentiate, activate angiogenesis and metastasis arise precisely due to the stemness of CSCs. These cells can be used as a target for therapy of different types of cancer. Laboratory models are needed to study cancer biology and find new therapeutic strategies. A promising direction is three-dimensional tumor models or spheroids. Such models exhibit properties resembling stemness in a natural tumor. By modifying spheroids, it becomes possible to investigate the effect of therapy on CSCs, thus contributing to the development of anti-tumor drug test systems. The review examines the niche of CSCs, the possibility of their study using three-dimensional spheroids, and existing markers for assessing stemness of CSCs.

Extracellular vesicles secreted by triple-negative breast cancer stem cells trigger premetastatic niche remodeling and metastatic growth in the lungs

Tumor secreted extracellular vesicles (EVs) are potent intercellular signaling platforms. They are responsible for the accommodation of the premetastatic niche (PMN) to support cancer cell engraftment and metastatic growth. However, complex cancer cell composition within the tumor increases also the heterogeneity among cancer secreted EVs subsets, a functional diversity that has been poorly explored. This phenomenon is particularly relevant in highly plastic and heterogenous triple-negative breast cancer (TNBC), in which a significant representation of malignant cancer stem cells (CSCs) is displayed. Herein, we selectively isolated and characterized EVs from CSC or differentiated cancer cells (DCC; EVs^CSC and EVs^DCC , respectively) from the MDA-MB-231 TNBC cell line. Our results showed that EVs^CSC and EVs^DCC contain distinct bioactive cargos and therefore elicit a differential effect on stromal cells in the TME. Specifically, EVs^DCC activated secretory cancer associated fibroblasts (CAFs), triggering IL-6/IL-8 signaling and sustaining CSC phenotype maintenance. Complementarily, EVs^CSC promoted the activation of α-SMA+ myofibroblastic CAFs subpopulations and increased the endothelial remodeling, enhancing the invasive potential of TNBC cells in vitro and in vivo. In addition, solely the EVs^CSC mediated signaling prompted the transformation of healthy lungs into receptive niches able to support metastatic growth of breast cancer cells.

The roles and clinical applications of interleukins in endometrial carcinoma

As a common malignant tumor of the female reproductive system, endometrial carcinoma (EC) seriously endangers women's health with an increasing incidence. The oncogenesis and progression of cancer are closely linked with immune microenvironment, of which interleukins are the important components. In order to illustrate the roles and clinical applications of interleukins in EC, literature of interleukins and EC were reviewed. Based on the present studies, interleukins play crucial roles in the oncogenesis and development of EC via regulating the proliferation, migration, invasion, angiogenesis, apoptosis, pyroptosis and autophagy of EC as well as the immune function against EC. And some of the interleukins seems to have prospective clinical applications in EC, such as evaluating the risk of tumorigenesis, discriminating the malignancy from benign disorders or normal condition, indicating cancer aggressiveness, predicting the prognosis of patients and serving as the novel therapy. However, there is still a long way to go before the clinical applications of interleukins in EC come into reality. Nevertheless, it is certain that the exploration of interleukins will definitely be of great benefit to the screening, diagnosis and treatment of EC in the future.

Natural compounds as a potential modifier of stem cells renewal: Comparative analysis

Cancer stem cells (CSCs) are indispensable for development, progression, drug resistance, and tumor metastasis. Current cancer-directed interventions target targeting rapidly dividing cancer cells and slow dividing CSCs, which are the root cause of cancer origin and recurrence. The most promising targets include several self-renewal pathways involved in the maintenance and renewal of CSCs, such as the Wnt/β-Catenin, Sonic Hedgehog, Notch, Hippo, Autophagy, and Ferroptosis. In view of safety, natural compounds are coming to the front line of treatment modalities for modifying various signaling pathways simultaneously involved in maintaining CSCs. Therefore, targeting CSCs with natural compounds is a promising approach to treating various types of cancers. In view of this, here we provide a comprehensive update on the current status of natural compounds that effectively tune key self-renewal pathways of CSCs. In addition, we highlighted surface expression markers in several types of cancer. We also emphasize how natural compounds target these self-renewal pathways to reduce therapy resistance and cancer recurrence properties of CSCs, hence providing valuable cancer therapeutic strategies. The inclusion of nutraceuticals is believed to enhance the therapeutic efficacy of current cancer-directed interventions significantly.

Small secretory proteins of immune cells can modulate gynecological cancers

Small secretory proteins of immune cells are mostly Cytokines, which include chemokines, interleukins, interferons, lymphokines and tumor necrosis factors but not hormones or growth factors. These secretory proteins are the molecular messengers and primarily involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Hence, these proteins actually regulate the cells of immune system to communicate with one another to produce a synchronized, robust, still self-regulated response to a specific antigen. Chemokines are smaller secreted proteins that control overall immune cell movement and location; these chemokines are divided into 4 subgroups, namely, CXC, CC, CX3C and C according to the position of 4 conserved cysteine residues. Complete characterization of cytokines and chemokines can exploit their vast signaling networks to develop cancer treatments. These secretory proteins like IL-6, IL-10, IL-12, TNFα, CCL2, CXCL4 & CXCL8 are predominantly expressed in most of the gynecological cancers, which directly stimulate immune effector cells and stromal cells at the tumor site and augment tumor cell recognition by cytotoxic T-cells. Hence; these secretory proteins are the major regulators, which can actually modulate all kinds of gynecological cancers. Furthermore, advancements in adoptive T-cell treatment have relied on the use of multiple cytokines/chemokines to establish a highly regulated environment for anti-tumor T cell growth. A number of in vitro studies as well as animal models and clinical subjects have also shown that cytokines/chemokines have broad antitumor activity, which has been translated into a number of cancer therapy approaches. This review will focus on the foremost cytokines & chemokines involved in the majority of the gynecological malignancies and discuss their basic biology as well as clinical applications.

STAT3 inactivation suppresses stemness properties in gastric cancer stem cells and promotes Th17 in Treg/Th17 balance

Signal transducer and activator of transcription 3 (STAT3) has been recognized with dual effects in provision of cancer; either tumor inductive or immune suppressive. Recent findings considering the role of STAT3 in stem cells and cancer stem cell regulation, but its role in gastric cancer stem cells (GCSCs) and modulating the Th17/Treg balance is unknown. In the present study, we aimed to evaluate the role of activated STAT3 in GCSCs and Th17/ Treg cell paradigm. In completion of our previous results, the findings here indicate that gastro-spheroids, as a model of GCSCs, represent higher level of STAT3 activity, up-regulation of TGF-b and VEGF with downregulation of IL-6. On the other hand, treatment of normal naïve T cells with conditioned medium derived from gastro-spheroids promotes T cell differentiation toward cells with a higher level of FOXP3, TGF-b, and IL-10 expression which is indicative of Treg cells. Suppression of STAT3 activation in cancer cells by using Stattic small molecule treatment, decreases stemness features (i.e. spheroid formation and integrity, stemness gene expression and in vivo tumorigenicity capacity) and downregulates TGF-b in the cancer cells. Furthermore, co-culture of conditioned medium of STAT3 inhibited cancer cells with normal PBMCs leads to reduction in the percentage of Treg accompanied with increase of Th17 cells with a decrease in the secretion of TGF-b and increase in IFN-γ in T cells under differentiation. Therefore, targeting the STAT3 pathway in cancer cells seems to control the tumor formation and also impact on immune cells shifting to antitumor Th17 population.

Gp130-Mediated STAT3 Activation Contributes to the Aggressiveness of Pancreatic Cancer through H19 Long Non-Coding RNA Expression

Simple Summary

The signal transducer and activator of transcription 3 (STAT3) activation correlate with the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). We demonstrated that the autocrine/paracrine interleukin-6 (IL-6) or leukemia inhibitory factor (LIF)/glycoprotein 130 (gp130)/STAT3 pathway contributes to the maintenance of stemness features and membrane-type 1 matrix metalloproteinase (MT1-MMP) expression, and modulates transforming growth factor (TGF)-β1/Smad signaling-mediated epithelial-mesenchymal transition (EMT) and invasion through regulation of TGFβ-RII expression in PDAC cancer stem cell (CSC)-like cells. Furthermore, we demonstrated that p-STAT3 acts through the IL-6 or LIF/gp130/STAT3 pathway to access the active promoter region of metastasis-related long non-coding RNA H19 and contribute to its transcription in CSC-like cells. Therefore, the autocrine/paracrine IL-6 or LIF/gp130/STAT3 pathway in PDAC CSC-like cells exhibiting H19 expression is considered to be involved in the aggressiveness of PDAC, and inhibition of the gp130/STAT3 pathway is a promising strategy to target CSCs for the elimination of PDAC (146/150).

Abstract

Signaling pathways involving signal transducer and activator of transcription 3 (STAT3) play key roles in the aggressiveness of pancreatic ductal adenocarcinoma (PDAC), including their tumorigenesis, invasion, and metastasis. Cancer stem cells (CSCs) have been correlated with PDAC aggressiveness, and activation of STAT3 is involved in the regulation of CSC properties. Here, we investigated the involvement of interleukin-6 (IL-6) or the leukemia inhibitory factor (LIF)/glycoprotein 130 (gp130)/STAT3 pathway and their role in pancreatic CSCs. In PDAC CSC-like cells formed by culturing on a low attachment plate, autocrine/paracrine IL-6 or LIF contributes to gp130/STAT3 pathway activation. Using a gp130 inhibitor, we determined that the gp130/STAT3 pathway contributes to the maintenance of stemness features, the expression of membrane-type 1 matrix metalloproteinase (MT1-MMP), and the invasion of PDAC CSC-like cells. The gp130/STAT3 pathway also modulates the transforming growth factor (TGF)-β1/Smad pathway required for epithelial-mesenchymal transition induction through regulation of TGFβ-RII expression in PDAC CSC-like cells. Furthermore, chromatin immunoprecipitation assays revealed that p-STAT3 can access the active promoter region of H19 to influence this metastasis-related long non-coding RNA and contribute to its transcription in PDAC CSC-like cells. Therefore, the autocrine/paracrine IL-6 or LIF/gp130/STAT3 pathway in PDAC CSC-like cells may eventually facilitate invasion and metastasis, two hallmarks of malignancy. We propose that inhibition of the gp130/STAT3 pathway provides a promising strategy for targeting CSCs for the treatment of PDAC.

Sera Protein Signatures of Endometrial Cancer Lymph Node Metastases

The presence of lymph node metastases in endometrial cancer patients is a critical factor guiding treatment decisions; however, surgical and imaging methods for their detection are limited by morbidity and inaccuracy. To determine if sera can predict the presence of positive lymph nodes, sera collected from endometrial cancer patients with or without lymph node metastases, and benign gynecology surgical patients (N = 20 per group) were subjected to electron spray ionization mass spectrometry (ES-MS). Peaks that were significantly different among the groups were evaluated by leave one out cross validation (LOOCV) for their ability to differentiation between the groups. Proteins in the peaks were identified by MS/MS of five specimens in each group. Ingenuity Pathway Analysis was used to predict pathways regulated by the protein profiles. LOOCV of sera protein discriminated between each of the group comparisons and predicted positive lymph nodes. Pathways implicated in metastases included loss of PTEN activation and PI3K, AKT and PKA activation, leading to calcium signaling, oxidative phosphorylation and estrogen receptor-induced transcription, leading to platelet activation, epithelial-to-mesenchymal transition and senescence. Upstream activators implicated in these events included neurostimulation and inflammation, activation of G-Protein-Coupled Receptor Gβγ, loss of HER-2 activation and upregulation of the insulin receptor.

Signal transducer and activator of transcription family is a prognostic marker associated with immune infiltration in endometrial cancer

BACKGROUND

Signal transducer and activator of transcription (STAT) is a unique protein family that binds to DNA and plays a vital role in regulating major physiological cellular processes. Seven STAT genes have been identified in the human genome. Several studies suggest STAT family members to be involved in cancer development, progression, and metastasis. However, the predictive relationship between STAT family expression and immune cell infiltration in endometrial cancer remains unknown.

METHODS

We explored STAT family expression and prognosis in endometrial cancer using various databases. The STRING, GeneMANIA, and DAVID databases, along with GO and KEGG analyses, were used to construct a protein interaction network of related genes. Finally, the TIMER database and ssGSEA immune infiltration algorithm were used to investigate the correlation of STAT family expression with the immune infiltration level in uterine corpus endometrial carcinoma (UCEC).

RESULTS

Our study showed that different STAT family members are differentially expressed in UCEC. STAT1 and STAT2 expression increased at various stages of UCEC, and STAT5A, STAT5B, and STAT6 levels were decreased. STAT3 and STAT4 expression was not significantly different between UCEC and normal tissues. High STAT1 expression may be a prognostic disadvantage of UCEC, and high STAT6 expression may improve UCEC patient prognosis. The STAT family-associated genes were significantly enriched in signal transduction, protein binding, DNA binding, and ATP binding upon GO analysis. Related genes in the KEGG analysis were mainly enriched in pathways in cancer, viral carcinogenesis, chemokine signaling pathway, JAK/STAT signaling pathway, and regulation of the actin cytoskeleton. In terms of immune infiltration, STAT1 and STAT2 were positively correlated with B, CD8+ T, CD4+ T, and dendritic cells, and neutrophils (p < 0.05). All STAT family members were positively correlated with neutrophils and dendritic cells (p < 0.05). STAT1 and STAT2 showed similar correlations with all immune cell types, whereas STAT1 and STAT6 showed opposite correlations.

CONCLUSION

These findings suggest that the STAT family is a prognostic marker, and the immune infiltration level, a therapeutic target, for endometrial cancer.

Adipocytokines and disease progression in endometrial cancer: a systematic review

The objective of the study was to document the effect of adipocytokines on endometrial cancer progression. A search of the databases CINAHL, Medline, PubMed, Cochrane, Web of Science, Embase and Google Scholar was performed for English language articles from January 2000 to December 2020 using the keywords: (Endometrial cancer) AND (progression OR metastasis) AND (adipocytokine OR adiponectin OR leptin OR visfatin OR IL-6 OR TNF-α OR adipokine OR cytokine). Forty-nine studies on adipocytokines have been included in this review. Adiponectin has been linked with anti-proliferative and anti-metastatic effects on endometrial cancer cells and is associated with a better prognosis. Leptin, visfatin and resistin are linked to the stimulation of endometrial cancer growth, proliferation, invasion and metastasis and are associated with worse prognosis or with a higher grade/stage of endometrial cancer. IL-6, Il-11, IL-31, IL-33, TNF-α, TGF-β1, SDF-1 and CXCR are involved in endometrial cancer cell growth and metastasis or involved in epithelial mesenchymal transformation (EMT) or associated with advanced disease. Adipocytokines have been found to directly impact endometrial cancer cell proliferation, invasion and migration. These molecules and their signalling pathways may be used to determine prognosis and course of the disease and may also be exploited as potential targets for cancer treatment and prevention of progression.

Recent Advances in Ovarian Cancer: Therapeutic Strategies, Potential Biomarkers, and Technological Improvements

Aggressive and recurrent gynecological cancers are associated with worse prognosis and a lack of effective therapeutic response. Ovarian cancer (OC) patients are often diagnosed in advanced stages, when drug resistance, angiogenesis, relapse, and metastasis impact survival outcomes. Currently, surgical debulking, radiotherapy, and/or chemotherapy remain the mainstream treatment modalities; however, patients suffer unwanted side effects and drug resistance in the absence of targeted therapies. Hence, it is urgent to decipher the complex disease biology and identify potential biomarkers, which could greatly contribute to making an early diagnosis or predicting the response to specific therapies. This review aims to critically discuss the current therapeutic strategies for OC, novel drug-delivery systems, and potential biomarkers in the context of genetics and molecular research. It emphasizes how the understanding of disease biology is related to the advancement of technology, enabling the exploration of novel biomarkers that may be able to provide more accurate diagnosis and prognosis, which would effectively translate into targeted therapies, ultimately improving patients’ overall survival and quality of life.

AZD3759 enhances radiation effects in non-small-cell lung cancer by a synergistic blockade of epidermal growth factor receptor and Janus kinase-1

AZD3759 is a novel epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) on the basis of gefitinib and has been proven to enter the central nervous system. Although the promising antitumor effects of AZD3759 on non-small cell lung cancer (NSCLC) have been demonstrated in clinical trials, the regulatory effects of this inhibitor on the antitumor efficacy of radiation (RA) are unclear. The present study aimed to compare the effects of AZD3759 and osimertinib on RA efficacy in NSCLC and explore the potential mechanism of action of AZD3759. We found that the survival in RA-treated NSCLC cells was significantly decreased by treatment with 500 nM AZD3759 and osimertinib at the RA dosage of 8 Gy. The apoptotic rate, cell cycle arrest, and DNA damage in RA-treated NSCLC cells and brain metastasis in RA-treated xenograft nude mice were significantly enhanced by the co-administration of AZD3759 and osimertinib, respectively. In addition, AZD3759 showed a significantly stronger efficacy than osimertinib did. Mechanistically, the receptor tyrosine kinase signaling antibody array revealed that Janus kinase-1 (JAK1) was specifically inhibited by AZD3759, but not by osimertinib. The effects of AZD3759 on RA efficacy in PC-9 cells and in a brain metastasis animal model were significantly abolished by the overexpression of JAK1. Collectively, our results suggested that AZD3759 promoted RA antitumor effects in NSCLC by synergistic blockade of EGFR and JAK1.

In vitro modelling of the physiological and diseased female reproductive system

The maladies affecting the female reproductive tract (FRT) range from infections to endometriosis to carcinomas. In vitro models of the FRT play an increasingly important role in both basic and translational research, since the anatomy and physiology of the FRT of humans and other primates differ significantly from most of the commonly used animal models, including rodents. Using organoid culture to study the FRT has overcome the longstanding hurdle of maintaining epithelial phenotype in culture.  Both ECM-derived and engineered materials have proved critical for maintaining a physiological phenotype of FRT cells in vitro by providing the requisite 3D environment, ligands, and architecture. Advanced materials have also enabled the systematic study of factors contributing to the invasive metastatic processes. Meanwhile, microphysiological devices make it possible to incorporate physical signals such as flow and cyclic exposure to hormones. Going forward, advanced materials compatible with hormones and optimised to support FRT-derived cells' long-term growth, will play a key role in addressing the diverse array of FRT pathologies and lead to impactful new treatments that support the improvement of women's health. STATEMENT OF SIGNIFICANCE: The female reproductive system is a crucial component of the female anatomy. In addition to enabling reproduction, it has wide ranging influence on tissues throughout the body via endocrine signalling. This intrinsic role in regulating normal female biology makes it susceptible to a variety of female-specific diseases. However, the complexity and human-specific features of the reproductive system make it challenging to study. This has spurred the development of human-relevant in vitro models for helping to decipher the complex issues that can affect the reproductive system, including endometriosis, infection, and cancer. In this Review, we cover the current state of in vitro models for studying the female reproductive system, and the key role biomaterials play in enabling their development.

7S,15R-Dihydroxy-16S,17S-Epoxy-Docosapentaenoic Acid, a Novel DHA Epoxy Derivative, Inhibits Colorectal Cancer Stemness through Repolarization of Tumor-Associated Macrophage Functions and the ROS/STAT3 Signaling Pathway

Colorectal cancer is a highly malignant cancer that is inherently resistant to many chemotherapeutic drugs owing to the complicated tumor-supportive microenvironment (TME). Tumor-associated macrophages (TAM) are known to mediate colorectal cancer metastasis and relapse and are therefore a promising therapeutic target. In the current study, we first confirmed the anti-inflammatory effect of 7S,15R-dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA), a novel DHA dihydroxy derivative synthesized in our previous work. We found that diHEP-DPA significantly reduced lipopolysaccharide (LPS)-induced inflammatory cytokines secretion of THP1 macrophages, IL-6, and TNF-α. As expected, diHEP-DPA also modulated TAM polarization, as evidenced by decreased gene and protein expression of the TAM markers, CD206, CD163, VEGF, and TGF-β1. During the polarization process, diHEP-DPA treatment decreased the concentration of TGF-β1, IL-1β, IL-6, and TNF-α in culture supernatants via inhibiting the NF-κB pathway. Moreover, diHEP-DPA blocked immunosuppression by reducing the expression of SIRPα in TAMs and CD47 in colorectal cancer cells. Knowing that an inflammatory TME largely serves to support epithelial-mesenchymal transition (EMT) and cancer stemness, we tested whether diHEP-DPA acted through polarization of TAMs to regulate these processes. The intraperitoneally injected diHEP-DPA inhibited tumor growth when administered alone or in combination with 5-fluorouracil (5-FU) chemotherapy in vivo. We further found that diHEP-DPA effectively reversed TAM-conditioned medium (TCCM)-induced EMT and enhanced colorectal cancer stemness, as evidenced by its inhibition of colorectal cancer cell migration, invasion and expression of EMT markers, as well as cancer cell tumorspheres formation, without damaging colorectal cancer cells. DiHEP-DPA reduced the population of aldehyde dehydrogenase (ALDH)-positive cells and expression of colorectal stemness marker proteins (CD133, CD44, and Sox2) by modulating TAM polarization. Additionally, diHEP-DPA directly inhibited cancer stemness by inducing the production of reactive oxygen species (ROS), which, in turn, reduced the phosphorylation of nuclear signal transducer and activator of transcription 3 (STAT3). These data collectively suggest that diHEP-DPA has the potential for development as an anticancer agent against colorectal cancer.

Andrographolide Inhibition of Th17-Regulated Cytokines and JAK1/STAT3 Signaling in OVA-Stimulated Asthma in Mice

Asthma has long been considered a disease of airway inflammation. The excessive or prolonged production of inflammatory mediators can result in airway remodeling and severe clinical syndromes such as dyspnea or even apnea. Therefore, pharmaceutical intervention is required to restrain the excessive release of such inflammatory mediators in control of asthma. Novel therapeutics and mechanistic insight are sought for the management of this chronic inflammatory disease. Andrographolide (AG) is a type of diterpenoid ester compound and is reported to demonstrate multiple properties such as antioxidation and anti-inflammation. However, the anti-inflammatory capacity of AG by regulating immunologic function in airway of asthma has not been fully studied to date. Therefore, this study investigates whether AG is capable of suppressing the inflammatory response of asthma in OVA-stimulated mice and the mechanism by which this is achieved. Animals were randomly divided into 4 groups: control group, OVA model group, OVA + AG (0.1 mg/ml) group, and OVA + dimethylsulfoxide (DMSO) group. The serum, BALF, and lung tissue of the mice were collected separately for the administration of ELISA, rt-PCR, western blot and pathological section and staining. We found that AG attenuated the OVA-induced production of IL-6, IL-17A, IL-17F, and RORγt; inhibited the OVA-mediated phosphorylation of JAK 1 and STAT3; and alleviated airway remodeling and the neutrophil infiltration of lung tissue. We conclude that AG inhibits the inflammatory response of asthma in OVA-stimulated mice by blocking the activation of Th17-regulated cytokines and the JAK1/STAT3 signaling pathway.

Dipeptidyl peptidase IV is required for endometrial carcinoma cell proliferation and tumorigenesis via the IL-6/STAT3 pathway

AIM

To study the functions and signaling pathways controlled by dipeptidyl peptidase IV (DPPIV) in endometrial carcinoma (EC).

METHODS

DPPIV expression in EC cells was detected by flow cytometry, reverse transcription-polymerase chain reaction analysis and Western blot. Interleukin-6 (IL-6) expression in the supernatant was measured by enzyme-linked immunosorbent assay. The protein levels of signal transducers and activators of transcription-3 (STAT3), phosphorylate STAT3, cellular Myc, and vascular endothelial growth factor in EC cells were measured by Western blot. Colony formation assays were used to assess the clonogenicity of EC cells. Ki67 immunostaining and cell counting were used to test the proliferative ability of EC cells. Nude mouse tumorigenicity assay was used to confirm DPPIV promotes the tumorigenicity of EC cells. A cell counting kit-8 assay was used to determine the half-maximal inhibitory concentration of sitagliptin.

RESULTS

Overexpression of DPPIV in EC cells with low DPPIV expression promoted cell proliferation in vitro (p < 0.01) and enhanced tumorigenicity in vivo (p < 0.05). Conversely, knocking down DPPIV expression in EC cells with high DPPIV expression inhibited cell proliferation (p < 0.01) and in vivo tumorigenicity (p < 0.01). DPPIV promoted EC cell proliferation via activation of IL-6/STAT3 signaling pathway, and that IL-6 could trigger a positive feedback loop that increased DPPIV expression (p < 0.01). Furthermore, the DPPIV inhibitor reduced STAT3 expression (p < 0.01) and inhibited growth of EC cells (p < 0.001).

CONCLUSION

DPPIV enhances the properties that allow tumorigenesis in EC via IL-6 and STAT3 signaling.

miR-20a-5p inhibits endometrial cancer progression by targeting janus kinase 1

Endometrial cancer (EC) is a multi-factorial disease of which pathogenesis has not been fully elucidated. The function and underlying mechanism of microRNA-20a-5p (miR-20a-5p) in EC remain poorly understood. The present study aimed to analyze the association between miR-20a-5p expression and the clinicopathological characteristics of patients with EC. Whether miR-20a-5p could inhibit EC progression by targeting janus kinase 1 (Jak1) was subsequently investigated. To do so, human EC tissues and paracancerous tissues were collected from 47 patients with EC. miR-20a-5p and Jak1 mRNA and protein expression was determined by reverse transcription quantitative PCR and western blotting, respectively. Cell proliferation, invasive ability and adhesion were investigated by MTT, Matrigel invasion and cell adhesion assays, respectively. Dual luciferase reporter assay was used to verify whether miR-20a-5p could directly target Jak1. The results demonstrated that miR-20a-5p was downregulated and that Jak1 was upregulated in EC tissues compared with paracancerous tissues. In addition, miR-20a-5p expression and Jak1 expression level were negatively correlated in EC tissues. miR-20a-5p expression was also significantly associated with the depth of myometrial invasion, FIGO stage, histologic grade and lymph node metastasis in patients with EC. Furthermore, Jak1 was identified as a new direct target of miR-20a-5p, and Jak1 overexpression was demonstrated to reverse the effects of miR-20a-5p-mimic on EC cell proliferation, invasive ability and adhesion. Taken together, the results from this study revealed for the first time that miR-20a-5p expression was significantly associated with the clinicopathological characteristics of patients with EC. These findings suggested that miR-20a-5p may act as a tumor suppressor in EC, in part through decreasing Jak1 expression. miR-20a-5p and Jak1 may therefore serve as potential therapeutic targets in EC.

Integration of genome-wide association study and expression quantitative trait locus mapping for identification of endometriosis-associated genes

To determine whether genetic predisposition to endometriosis varies depending on ethnicity and in association with expression quantitative trait loci (eQTL) in a Taiwanese population. We conducted a genome-wide association study (GWAS) and replicated it in 259 individuals with laparoscopy-confirmed stage III or IV endometriosis (cases) and 171 women without endometriosis (controls). Their genomic DNA was extracted from blood and evaluated by the GWAS of Taiwan Biobank Array. Novel genetic variants that predispose individuals to endometriosis were identified using GWAS and replication, including rs10739199 (P = 6.75 × 10^-5) and rs2025392 (P = 8.01 × 10^-5) at chromosome 9, rs1998998 (P = 6.5 × 10^-6) at chromosome 14, and rs6576560 (P = 9.7 × 10^-6) at chromosome 15. After imputation, strong signals were exhibited by rs10822312 (P = 1.80 × 10^-7) at chromosome 10, rs58991632 (P = 1.92 × 10^-6) and rs2273422 (P = 2.42 × 10^-6) at chromosome 20, and rs12566078 (P = 2.5 × 10^-6) at chromosome 1. We used the Genotype-Tissue Expression (GTEx) database to observe eQTL. Among these SNPs, the cis-eQTL rs13126673 of inturned planar cell polarity protein (INTU) showed significant association with INTU expression (P = 5.1 × 10^-33). Moreover, the eQTL analysis was performed on endometriotic tissues from women with endometriosis. The expression of INTU in 78 endometriotic tissue of women with endometriosis is associated with rs13126673 genotype (P = 0.034). To our knowledge, this is the first GWAS to link endometriosis and eQTL in a Taiwanese population.

Aspirin mediates histone methylation that inhibits inflammation-related stemness gene expression to diminish cancer stemness via COX-independent manner

Background

The widely recognized anti-cancer potential of aspirin has created a broad interest to explore the clinical benefits of aspirin in cancer therapy. However, the current understanding of the molecular mechanisms involved in the anti-cancer potential of aspirin remains limited.

Methods

Cancer stemness assays which contained ALDH, side population, chemo-resistance, sphere formation, and tumorigenesis were performed to validate aspirin function in vitro and in vivo. Histone modification assay was performed to check the effect of aspirin on histone methylation as well as the activity of HDAC and KDM6A/B. Inhibitor in vivo assay was performed to evaluate therapeutic effects of various inhibitor combination manners.

Results

In regards to in vitro studies, aspirin diminishes cancer cell stemness properties which include reducing the ALDH+ subpopulation, side population, chemo-resistance, and sphere formation in three cancer types. In regards to in vivo studies, aspirin decreases tumor growth and metastasis and prolongs survival. In addition, our results showed that aspirin inhibits inflammation-related stemness gene expression (especially ICAM3) identified by a high-throughput siRNA platform. In regards to the underlying molecular mechanism of action, aspirin reduces histone demethylase (KDM6A/B) expression that mediates histone methylation and suppresses gene expression via a COX-independent manner. In regards to therapeutic strategies, aspirin combined HDM inhibitors, ICAM3 downstream signaling Src/PI3K inhibitors, or ICAM3 inhibitor Lifitigrast prevents cancer progression in vivo.

Conclusions

The aforementioned findings suggest a molecular model that explains how aspirin diminishes cancer cell stemness properties. These findings may provide novel targets for therapeutic strategies involving aspirin in the prevention of cancer progression.

CLEC4M overexpression inhibits progression and is associated with a favorable prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains the most common malignant cancer worldwide. Numerous studies have indicated that C-type lectin domain family 4 member M (CLEC4M) is associated with tumor progression; however, the biological functions of CLEC4M in HCC have not been investigated. In the present study, CLEC4M overexpression was observed to be associated with a favorable patient overall, relapse-free, progression-free and disease-specific survival by using the KMplot™ database. The present study then concentrated specifically on the functions of CLEC4M by performing cell counting kit-8 proliferation, 5-Ethynyl-2′-deoxyuridine and flow cytometric assays. CLEC4M overexpression inhibited proliferation and enhanced apoptosis in Huh7 and PLC/PRF/5 cells. Furthermore, the results demonstrated by using western blotting that CLEC4M overexpression inhibited the Janus kinase 1/signal transducer and activator of transcription 3 pathway, which is involved in various types of tumors including HCC. In conclusion, the present study reported that CLEC4M may be considered as a novel indicator of HCC and may provide a theoretical basis for improving the survival of patients with HCC.

Ibuprofen mediates histone modification to diminish cancer cell stemness properties via a COX2-dependent manner

Background

The anticancer potential of ibuprofen has created a broad interest to explore the clinical benefits of ibuprofen in cancer therapy. However, the current understanding of the molecular mechanisms involved in the anticancer potential of ibuprofen remains limited.

Methods

Cancer stemness assays to validate ibuprofen function in vitro and in vivo. Histone modification assays to check the effect of ibuprofen on histone acetylation/methylation, as well as the activity of HDAC and KDM6A/B. Inhibitors’ in vivo assays to evaluate therapeutic effects of various inhibitors’ combination manners.

Results

In our in vitro studies, we report that ibuprofen diminishes cancer cell stemness properties that include reducing the ALDH + subpopulation, side population and sphere formation in three cancer types. In our in vivo studies, we report that ibuprofen decreases tumour growth, metastasis and prolongs survival. In addition, our results showed that ibuprofen inhibits inflammation-related stemness gene expression (especially ICAM3) identified by a high-throughput siRNA platform. In regard to the underlying molecular mechanism of action, we report that ibuprofen reduces HDACs and histone demethylase (KDM6A/B) expression that mediates histone acetylation and methylation, and suppresses gene expression via a COX2-dependent way. In regard to therapeutic strategies, we report that ibuprofen combined HDAC/HDM inhibitors prevents cancer progression in vivo.

Conclusions

The aforementioned findings suggest a molecular model that explains how ibuprofen diminishes cancer cell stemness properties. These may provide novel targets for therapeutic strategies involving ibuprofen in the prevention of cancer progression.

Targeting Aldehyde Dehydrogenases to Eliminate Cancer Stem Cells in Gynecologic Malignancies

Gynecologic cancers cause over 600,000 deaths annually in women worldwide. The development of chemoresistance after initial rounds of chemotherapy contributes to tumor relapse and death due to gynecologic malignancies. In this regard, cancer stem cells (CSCs), a subpopulation of stem cells with the ability to undergo self-renewal and clonal evolution, play a key role in tumor progression and drug resistance. Aldehyde dehydrogenases (ALDH) are a group of enzymes shown to be robust CSC markers in gynecologic and other malignancies. These enzymes also play functional roles in CSCs, including detoxification of aldehydes, scavenging of reactive oxygen species (ROS), and retinoic acid (RA) signaling, making ALDH an attractive therapeutic target in various clinical scenarios. In this review, we discuss the critical roles of the ALDH in driving stemness in different gynecologic malignancies. We review inhibitors of ALDH, both general and isoform-specific, which have been used to target CSCs in gynecologic cancers. Many of these inhibitors have been shown to be effective in preclinical models of gynecologic malignancies, supporting further development in the clinic. Furthermore, ALDH inhibitors, including 673A and CM037, synergize with chemotherapy to reduce tumor growth. Thus, ALDH-targeted therapies hold promise for improving patient outcomes in gynecologic malignancies.

Targeting cancer stem cell pathways for cancer therapy

Since cancer stem cells (CSCs) were first identified in leukemia in 1994, they have been considered promising therapeutic targets for cancer therapy. These cells have self-renewal capacity and differentiation potential and contribute to multiple tumor malignancies, such as recurrence, metastasis, heterogeneity, multidrug resistance, and radiation resistance. The biological activities of CSCs are regulated by several pluripotent transcription factors, such as OCT4, Sox2, Nanog, KLF4, and MYC. In addition, many intracellular signaling pathways, such as Wnt, NF-κB (nuclear factor-κB), Notch, Hedgehog, JAK-STAT (Janus kinase/signal transducers and activators of transcription), PI3K/AKT/mTOR (phosphoinositide 3-kinase/AKT/mammalian target of rapamycin), TGF (transforming growth factor)/SMAD, and PPAR (peroxisome proliferator-activated receptor), as well as extracellular factors, such as vascular niches, hypoxia, tumor-associated macrophages, cancer-associated fibroblasts, cancer-associated mesenchymal stem cells, extracellular matrix, and exosomes, have been shown to be very important regulators of CSCs. Molecules, vaccines, antibodies, and CAR-T (chimeric antigen receptor T cell) cells have been developed to specifically target CSCs, and some of these factors are already undergoing clinical trials. This review summarizes the characterization and identification of CSCs, depicts major factors and pathways that regulate CSC development, and discusses potential targeted therapy for CSCs.

Highlighted STAT3 as a potential drug target for cancer therapy

Signal transducer and activator of transcription 3 (STAT3) is a cytoplasmic transcription factor that regulates cell proliferation, differentiation, apoptosis, angiogenesis, inflammation and immune responses. Aberrant STAT3 activation triggers tumor progression through oncogenic gene expression in numerous human cancers, leading to promote tumor malignancy. On the contrary, STAT3 activation in immune cells cause elevation of immunosuppressive factors. Accumulating evidence suggests that the tumor microenvironment closely interacts with the STAT3 signaling pathway. So, targeting STAT3 may improve tumor progression, and anti-cancer immune response. In this review, we summarized the role of STAT3 in cancer and the tumor microenvironment, and present inhibitors of STAT3 signaling cascades.

Endometrial Cancer Stem Cells: Role, Characterization and Therapeutic Implications

Endometrial cancer (EC) is the most frequent gynecological cancer. In patients with relapsed and advanced disease, prognosis is still dismal and development of resistance is common. In this context, endometrial Cancer Stem Cells (eCSC), stem-like cells capable to self-renewal and differentiation in mature cancer cells, represent a potential field of expansion for drug development. The aim of this review is to characterize the role of eCSC in EC, their features and how they could be targeted. CSC are involved in progression, invasiveness and metastasis (though epithelial to mesenchimal transition, EMT), as well as chemoresistance in EC. Nevertheless, isolation of eCSC is still controversial. Indeed, CD133, Aldheyde dehydrogenase (ALDH), CD117, CD55 and CD44 are enriched in CSCs but there is no universal marker nowadays. The most frequently activated pathways in eCSC are Wingless-INT (Wnt)/β-catenin, Notch1, and Hedghog, with a high expression of self-renewal transcription factors like Octamer binding transcription factor 4 (OCT), B Lymphoma Mo-MLV Insertion Region 1 Homolog (BMI1), North American Network Operations Group Homebox protein (NANOG), and SRY-Box 2 (SOX2). These pathways have been targeted with selective drugs alone or in combination with chemotherapy and immunotherapy. Unfortunately, although preclinical results are encouraging, few clinical data are available.

ALDH-Dependent Glycolytic Activation Mediates Stemness and Paclitaxel Resistance in Patient-Derived Spheroid Models of Uterine Endometrial Cancer

Uterine endometrial cancer is associated with poor survival outcomes in patients with advanced-stage disease. Here, we developed a three-dimensional cell cultivation method of endometrioid cancer stem-like cells with high aldehyde dehydrogenase (ALDH) activity from clinical specimens. ALDH inhibition synergized with paclitaxel to block cancer proliferation. In the clinical setting, high ALDH1A1 expression was associated with poor survival. A high level of ALDH correlated with an increase of glucose uptake, activation of the glycolytic pathway, and elevation of glucose transporter 1 (GLUT1). Blockade of GLUT1 inhibited characteristics of cancer stem cells. Similarly to ALDH inhibition, GLUT1 inhibition synergized with paclitaxel to block endometrial cancer proliferation. Our data indicated that ALDH-dependent GLUT1 activation and the resulting glycolytic activation are of clinical importance for both prognostic evaluation and therapeutic decision-making in endometrial cancer patients. In addition, the synergistic effects of taxane compounds and ALDH or GLUT1 inhibitors may serve as a new clinical treatment option for endometrial cancer.

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Establishment of patient-derived endometrial cancer stem cells with ALDH activity

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Endometrial cancer stemness depends on ALDH-mediated glycolysis via GLUT1

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High ALDH and GLUT expression is associated with poor outcome in endometrial cancer

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Paclitaxel and ALDH or GLUT inhibitor synergistically suppress endometrial cancer

Autophagy and Its Relationship to Epithelial to Mesenchymal Transition: When Autophagy Inhibition for Cancer Therapy Turns Counterproductive

The manipulation of autophagy for cancer therapy has gained recent interest in clinical settings. Although inhibition of autophagy is currently being used in clinical trials for the treatment of several malignancies, autophagy has been shown to have diverse implications for normal cell homeostasis, cancer cell survival, and signaling to cells in the tumor microenvironment. Among these implications and of relevance for cancer therapy, the autophagic process is known to be involved in the regulation of protein secretion, in tumor cell immunogenicity, and in the regulation of epithelial-to-mesenchymal transition (EMT), a critical step in the process of cancer cell invasion. In this work, we have reviewed recent evidence linking autophagy to the regulation of EMT in cancer and normal epithelial cells, and have discussed important implications for the manipulation of autophagy during cancer therapy.

Hormonal Regulation of Patient-Derived Endometrial Cancer Stem-like Cells Generated by Three-Dimensional Culture

Low-grade and early-stage endometrial cancer usually has a favorable prognosis, whereas recurrent or metastatic disease is often difficult to cure. Thus, the molecular mechanisms underlying advanced pathophysiology remain to be elucidated. From the perspective of the origin of advanced endometrial cancer, the characterization of cancer stem-like cells (CSCs) will be the first step toward the development of clinical management. We established long-term culturable patient-derived cancer cells (PDCs) from patient endometrial tumors by spheroid cell culture, which is favorable for the enrichment of CSCs. PDC-derived xenograft tumors were generated in immunodeficient NOD/Shi-scid, IL-2RγKO Jic mice. Morphologically, PDCs derived from three distinct patient samples and their xenograft tumors recapitulated the corresponding original patient tumors. Of note, CSC-related genes including ALDH1A1 were upregulated in all of these PDCs, and the therapeutic potentiality of aldehyde dehydrogenase inhibitors was demonstrated. In addition, these PDCs and their patient-derived xenograft (PDX) models exhibited distinct characteristics on the basis of their hormone responsiveness and metastatic features. Interestingly, genes associated with inflammation and tumor immunity were upregulated by 17β-estradiol in PDC lines with high estrogen receptor expression and were also overexpressed in secondary PDCs obtained from metastatic tumor models. These results suggest that PDC and PDX models from endometrial cancer specimens would be useful to elucidate CSC traits and to develop alternative diagnostic and therapeutic options for advanced disease.

Targeting Endometrial Cancer Stem Cell Activity with Metformin Is Inhibited by Patient-Derived Adipocyte-Secreted Factors

Advanced endometrial cancer continues to have a poor prognosis, due to limited treatment options, which may be further adversely impacted by obesity. Endometrial cancer stem cells have been reported to drive metastasis, chemotherapy resistance and disease relapse, but have yet to be fully characterised and no specific targeted therapies have been identified. Here, we describe the phenotype and genotype of aldehyde dehydrogenase high (ALDH^high) and CD133^+ve endometrial cancer stem cells and how adipocyte secreted mediators block the inhibitory effect of metformin on endometrial cancer stem cell activity. Ishikawa and Hec-1a cell lines were used to characterise ALDH^high and CD133^+ve endometrial cancer cells using flow cytometry, functional sphere assays and quantitative-Polymerase Chain Reaction. The comparative effect of metformin on endometrial cancer stem cell activity and bulk tumour cell proliferation was determined using an Aldefluor and cytotoxicity assay. The impact of adipocyte secreted mediators on metformin response was established using patient-derived conditioned media. ALDH^high cells demonstrated greater endometrial cancer stem cell activity than CD133^+ve cells and had increased expression of stem cell and epithelial-mesenchymal transition genes. Treatment with 0.5-1 mM metformin reduced the proportion and activity of both endometrial cancer stem cell populations (p ≤ 0.05), without affecting cell viability. This effect was, however, inhibited by exposure to patient-derived adipocyte conditioned media. These results indicate a selective and specific effect of metformin on endometrial cancer stem cell activity, which is blocked by adipocyte secreted mediators. Future studies of metformin as an adjuvant therapy in endometrial cancer should be adequately powered to investigate the influence of body mass on treatment response.

The inflammatory cytokine IL-6 induces FRA1 deacetylation promoting colorectal cancer stem-like properties

Colorectal cancer (CRC) has long been known for its tight association with chronic inflammation, thought to play a key role in tumor onset and malignant progression through the modulation of cancer stemness. However, the underlying molecular and cellular mechanisms are still largely elusive. Here we show that the IL-6/STAT3 inflammatory signaling axis induces the deacetylation of FRA1 at the Lys-116 residue located within its DNA-binding domain. The HDAC6 deacetylase underlies this key modification leading to the increase of FRA1 transcriptional activity, the subsequent transactivation of NANOG expression, and the acquisition of stem-like cellular features. As validated in a large (n = 123) CRC cohort, IL-6 secretion was invariably accompanied by increased FRA1 deacetylation at K116 and an overall increase in its protein levels, coincident with malignant progression and poor prognosis. Of note, combined treatment with the conventional cytotoxic drug 5-FU together with Tubastatin A, a HDAC6-specific inhibitor, resulted in a significant in vivo synergistic inhibitory effect on tumor growth through suppression of CRC stemness. Our results reveal a novel transcriptional and posttranslational regulatory cross-talk between inflammation and stemness signaling pathways that underlie self-renewal and maintenance of CRC stem cells and promote their malignant behavior. Combinatorial treatment aimed at the core regulatory mechanisms downstream of IL-6 may offer a novel promising approach for CRC treatment.

Modeling Endometrial Cancer: Past, Present, and Future

Endometrial cancer is the most common type of cancer of the female reproductive tract. Although prognosis is generally good for patients with low-grade and early-stage diseases, the outcomes for high-grade and metastatic/recurrent cases remain poor, since traditional chemotherapy regimens based on platinum and taxanes have limited effects. No targeted agents have been approved so far, although several new drugs have been tested without striking results in clinical trials. Over the last decades, many efforts have been made towards the establishment and development of preclinical models, aiming at recapitulating the structural and molecular determinants of the disease. Here, we present an overview of the most commonly used in vitro and in vivo models and discuss their peculiar features, describing their main applications and the value in the advancement of both fundamental and translational endometrial cancer research.

Evaluation of Vav3.1 as prognostic marker in endometrial cancer

PURPOSE

Vav3 is a guanine nucleotide exchange factor that regulates the activity of Rho/Rac family GTPases. In a study on ovarian cancer, we recently demonstrated pronounced prognostic and predictive value of Vav3.1, a specific truncation variant of the parental Vav3 gene. Here, we sought to investigate the role of Vav3.1 in the most prevalent gynecological tumor entity, endometrial cancer.

METHODS

Vav3.1 transcript levels were determined in a large cohort of endometrial cancer patients using variant-specific PCR (n = 239), and non-malignant endometrial tissue served as control (n = 26). Expression levels of Vav3.1 were stratified according to established clinicopathological characteristics and correlated to long-term patient survival (average follow-up of > 7.5 years). Type 1 and type 2 cancers were separately investigated.

RESULTS

While Vav3.1 was markedly overexpressed in endometrial cancer tissue, we could not detect associations with clinical parameters related to prognosis, such as FIGO stage and tumor grade. Kaplan-Meier estimators of different measures of survival failed to show prognostic significance of Vav3.1 in endometrial cancer. Lack of prognostic value was observed for both type 1 and type 2 cancers.

CONCLUSIONS

Our study shows that Vav3.1 is not suited as a marker of cancer progression and/or treatment response in endometrial cancer. Feasibility and potential benefit of targeting Vav3.1 in endometrial cancer needs to be evaluated in future studies, proceeding from its clear, roughly ten-fold, induction in the malignant endometrium.

Genetic overlap between endometriosis and endometrial cancer: evidence from cross-disease genetic correlation and GWAS meta-analyses

Epidemiological, biological, and molecular data suggest links between endometriosis and endometrial cancer, with recent epidemiological studies providing evidence for an association between a previous diagnosis of endometriosis and risk of endometrial cancer. We used genetic data as an alternative approach to investigate shared biological etiology of these two diseases. Genetic correlation analysis of summary level statistics from genomewide association studies (GWAS) using LD Score regression revealed moderate but significant genetic correlation (rg  = 0.23, P = 9.3 × 10-3 ), and SNP effect concordance analysis provided evidence for significant SNP pleiotropy (P = 6.0 × 10-3 ) and concordance in effect direction (P = 2.0 × 10-3 ) between the two diseases. Cross-disease GWAS meta-analysis highlighted 13 distinct loci associated at P ≤ 10-5 with both endometriosis and endometrial cancer, with one locus (SNP rs2475335) located within PTPRD associated at a genomewide significant level (P = 4.9 × 10-8 , OR = 1.11, 95% CI = 1.07-1.15). PTPRD acts in the STAT3 pathway, which has been implicated in both endometriosis and endometrial cancer. This study demonstrates the value of cross-disease genetic analysis to support epidemiological observations and to identify biological pathways of relevance to multiple diseases.

STAT3 activation by IL-6 from adipose-derived stem cells promotes endometrial carcinoma proliferation and metastasis

Endometrial cancer is the most common gynaecological cancer, and its incidence is increasing. Obesity is a well-recognized risk factor for endometrial cancer, and the mechanisms by which adipose tissue influences tumour development remain controversial. In this study, we examined the high IL-6 level in the ADSCs supernatant following treatment of endometrial cancer cell CM. Then, the activation of STAT3, a major tumourigenic IL-6 effector, was examined in ADSCs CM treated endometrial cancer cells. Conditioned ADSC medium was used to stimulate endometrial cancer cell growth in vitro. Similar to IL-6, ADSC-conditioned medium significantly promoted endometrial cancer growth and invasion. Furthermore, siRNA-mediated STAT3 inhibition in endometrial cancer cells decreased the ADSC-mediated promotion of cell proliferation and invasion. In addition, a subcutaneous nude mouse model of endometrial cancer was established to monitor the tumour-promoting effect of ADSCs. ADSC-conditioned medium promoted tumour growth, and STAT3 inhibition attenuated this effect. Based on these data, ADSCs promote endometrial cancer progression by the STAT3 signalling pathway.

Activation of signal transducer and activator of transcription 3 (STAT3) signaling in EGFR mutant non-small-cell lung cancer (NSCLC)

Gefitinib, erlotinib or afatinib are the current treatment for non-small-cell lung cancer (NSCLC) harboring an activating mutation of the epidermal growth factor receptor (EGFR), but less than 5% of patients achieve a complete response and the median progression-free survival is no longer than 12 months. Early adaptive resistance can occur as soon as two hours after starting treatment by activating signal transducer and activation of transcription 3 (STAT3) signaling. We investigated the activation of STAT3 in a panel of gefitinib-sensitive EGFR mutant cell lines, and gefitinib-resistant PC9 cell lines developed in our laboratory. Afatinib has great activity in gefitinib-sensitive as well as in gefitinib-resistant EGFR mutant NSCLC cell lines. However, afatinib therapy causes phosphorylation of STAT3 tyrosine 705 (pSTAT3_Tyr705) and elevation of STAT3 and RANTES mRNA levels. The combination of afatinib with TPCA-1 (a STAT3 inhibitor) ablated pSTAT3_Tyr705 and down-regulated STAT3 and RANTES mRNA levels with significant growth inhibitory effect in both gefitinib-sensitive and gefitinib-resistant EGFR mutant NSCLC cell lines. Aldehyde dehydrogenase positive (ALDH⁺) cells were still observed with the combination at the time that Hairy and Enhancer of Split 1 (HES1) mRNA expression was elevated following therapy. Although the combination of afatinib with STAT3 inhibition cannot eliminate the potential problem of a remnant cancer stem cell population, it represents a substantial advantage and opportunity to further prolong progression free survival and probably could increase the response rate in comparison to the current standard of single therapy.

Tumor-derived mesenchymal-stem-cell-secreted IL-6 enhances resistance to cisplatin via the STAT3 pathway in breast cancer

Cisplatin is used for the treatment of a range of solid malignant tumors; however, with prolonged treatment durations, the sensitivity of tumor cells to the drug decreases owing to an unclear mechanism of drug resistance. The present study aimed to investigate whether breast-cancer-tissue-derived mesenchymal stem cells (BC-MSCs) are involved in mediating the effects of cisplatin on breast cancer cells, and which component of the BC-MSC conditioned medium (BC-MSC-CM) exhibited an anti-apoptotic effect. Cytokines/chemokines in BC-MSC-CM were quantified using a Luminex immunoassay, and reverse transcription-quantitative polymerase chain reaction analysis detected interleukin-6 (IL-6) levels in MCF-7 cells following different treatments. MTT and flow cytometry analysis measured cell vitality and apoptosis, respectively, and activation of signal transduced and activator of transcription 3 (STAT3) was evaluated by western blotting. BC-MSCs reversed the pro-apoptotic effect of cisplatin and enhanced the proliferation of MCF-7 cells more potently than bone-marrow-derived MSCs. Further study revealed that BC-MSCs secreted IL-6 to protect MCF-7 cells from apoptosis and promote their survival. Neutralizing IL-6 with a specific antibody partially inhibited the IL-6/STAT3 signaling pathway and reversed the promoter role of BC-MSCs in MCF-7 cells. Taken together, the findings of the present study indicated that BC-MSCs decreased the level of cisplatin-induced apoptosis in MCF-7 cells by activating the IL-6/STAT3 pathway in cancer cells. BC-MSCs, as important cells in the tumor microenvironment, have a key role in the treatment of breast cancer.

ICAM3 mediates inflammatory signaling to promote cancer cell stemness

In this study, we present a medium throughput siRNA screen platform to identify inflammation genes that regulate cancer cell stemness. We identified several novel candidates that decrease OCT4 expression and reduce the ALDH + subpopulation both of which are characteristic of stemness. Furthermore, one of the novel candidates ICAM3 up-regulates in the ALDH + subpopulation, the side population and the developed spheres. ICAM3 knockdown reduces the side population, sphere formation and chemo-resistance in MDA-MB-231 human breast cancer cells and A549 lung cancer cells. In addition, mice bearing MDA-MB-231-shICAM3 cells develop smaller tumors and fewer lung metastases versus control. Interestingly, ICAM3 recruits and binds to Src by the YLPL motif in its intracellular domain which further activates the PI3K-AKT phosphorylation cascades. The activated p-AKT enhances SOX2 and OCT4 activity and thereby maintains cancer cell stemness. Meanwhile, the p-AKT facilitated p50 nuclear translocation/activation enhances p50 feedback and thereby promotes ICAM3 expression by binding to the ICAM3 promoter region. On this basis, Src and PI3K inhibitors suppress ICAM3-mediated signaling pathways and reduce chemo-resistance which results in tumor growth suppression in vitro and in vivo. In summary, we identify a potential CSC regulator and suggest a novel mechanism by which ICAM3 governs cancer cell stemness and inflammation.

DPPIV promotes endometrial carcinoma cell proliferation, invasion and tumorigenesis

Dipeptidyl peptidase IV (DPPIV), also known as CD26, is a 110-kDa cell surface glycoprotein expressed in various tissues. DPPIV reportedly plays a direct role in the progression of several human malignancies. DPPIV specific inhibitors are employed as antidiabetics and could potentially be repurposed to enhance anti-tumor immunotherapies. In the present study, we investigated the correlation between DPPIV expression and tumor progression in endometrial carcinoma (EC). DPPIV overexpression altered cell morphology and stimulated cell proliferation, invasion and tumorigenesis in vitro and in vivo. These effects were abrogated by DPPIV knockdown or pharmacological inhibition using sitagliptin. DPPIV overexpression increased hypoxia-inducible factor 1a (HIF-1a) and vascular endothelial growth factor A (VEGFA) expression to promote HIF-1a-VEGFA signaling. Our results indicated that DPPIV accelerated endometrial carcinoma progression and that sitagliptin may be an effective anti-EC therapeutic.

The Use of Endometrial Cancer Patient-Derived Organoid Culture for Drug Sensitivity Testing Is Feasible

OBJECTIVE

Patient-derived organoids (PDOs), used in multiple tumor types, have allowed evaluation of tumor characteristics from individual patients. This study aimed to assess the feasibility of applying PDO in vitro culture for endocrine-based and drug sensitivity testing in endometrial cancer.

METHODS

Endometrial cancer cells were enzymatically dissociated from tumors retrieved from fresh hysterectomy specimens and cultured within basement membrane extract in serum-free medium. An organoid growth assay was developed to assess the inhibitory effects of a variety of drugs including endocrine treatments. Organoid cultures were also prepared for histological and immunohistochemical comparison to the tumors of origin.

RESULTS

Fifteen endometrial cancer specimens were successfully cultured as PDOs. Small spherical structures formed within 24 hours, and many continued to grow to larger, denser organoids, providing the basis for an organoid growth assay. The STAT3 transcription factor inhibitor, BBI608 (Napabucasin), strongly inhibited growth in almost all PDO cultures, suggesting that stemness programing is involved in organoid formation and/or growth. Inhibition by different growth factor receptor tyrosine kinase inhibitors was observed in several PDO specimens. Four cultures were inhibited by fulvestrant, implying the importance of estrogen-receptor signaling in some PDO cultures. Organoids closely resembled their tumors of origin in both histomorphology and immunohistochemical expression.

CONCLUSIONS

The use of endometrial cancer PDO cultures for development of drug sensitivity testing for individual patient tumors is feasible. The potential value of the PDO model for clinical decision making will require clinical trial evaluation.

GMI ablates cancer stemness and cisplatin resistance in oral carcinomas stem cells through IL-6/Stat3 signaling inhibition

Cancer stem cells (CSCs) have been identified to exert tumor-initiating ability, resulting in the recurrence, metastasis and chemoresistance of oral squamous cell carcinomas. In the present study, we showed that GMI, an immunomodulatory protein from Ganoderma microsporum, induc ed a cytotoxic effect in oral carcinomas stem cells (OCSCs). Treatment of GMI dose-dependently inhibited the expression of CSC markers, including ALDH1 activity and CD44 positivity. Moreover, GMI suppressed the self-renewal property, colony formation, migration, and invasion abilities as well as potentiated chemo-sensitivity in OCSCs. Our results suggested that the tumor suppressive effect of GMI was mediated through inhibition of IL-6/Stat3 signaling pathway. Furthermore, tumor growth was reduced in mice bearing xenograft tumors after oral administration of GMI. Taken together, we demonstrated the anti-CSC effect of GMI in oral cancer and GMI may serve as a natural cisplatin adjuvant to prevent cancer recurrence.