Leukemia inhibitory factor receptor negatively regulates the metastasis of pancreatic cancer cells in vitro and in vivo

Immunology of bile acids regulated receptors

Bile acids are steroids formed at the interface of host metabolism and intestinal microbiota. While primary bile acids are generated in the liver from cholesterol metabolism, secondary bile acids represent the products of microbial enzymes. Close to 100 different enzymatic modifications of bile acids structures occur in the human intestine and clinically guided metagenomic and metabolomic analyses have led to the identification of an extraordinary number of novel metabolites. These chemical mediators make an essential contribution to the composition and function of the postbiota, participating to the bidirectional communications of the intestinal microbiota with the host and contributing to the architecture of intestinal-liver and -brain and -endocrine axes. Bile acids exert their function by binding to a group of cell membrane and nuclear receptors collectively known as bile acid-regulated receptors (BARRs), expressed in monocytes, tissue-resident macrophages, CD4+ T effector cells, including Th17, T regulatory cells, dendritic cells and type 3 of intestinal lymphoid cells and NKT cells, highlighting their role in immune regulation. In this review we report on how bile acids and their metabolitesmodulate the immune system in inflammations and cancers and could be exploiting for developing novel therapeutic approaches in these disorders.

Bile acids serve as endogenous antagonists of the Leukemia inhibitory factor (LIF) receptor in oncogenesis

The leukemia inhibitory factor (LIF) is member of interleukin (IL)-6 family of cytokines involved immune regulation, morphogenesis and oncogenesis. In cancer tissues, LIF binds a heterodimeric receptor (LIFR), formed by a LIFRβ subunit and glycoprotein(gp)130, promoting epithelial mesenchymal transition and cell growth. Bile acids are cholesterol metabolites generated at the interface of host metabolism and the intestinal microbiota. Here we demonstrated that bile acids serve as endogenous antagonist to LIFR in oncogenesis. The tissue characterization of bile acids content in non-cancer and cancer biopsy pairs from gastric adenocarcinomas (GC) demonstrated that bile acids accumulate within cancer tissues, with glyco-deoxycholic acid (GDCA) functioning as negative regulator of LIFR expression. In patient-derived organoids (hPDOs) from GC patients, GDCA reverses LIF-induced stemness and proliferation. In summary, we have identified the secondary bile acids as the first endogenous antagonist to LIFR supporting a development of bile acid-based therapies in LIF-mediated oncogenesis.

Targeting metastasis-initiating cancer stem cells in gastric cancer with leukaemia inhibitory factor

Gastric cancer's (GC) bad prognosis is usually associated with metastatic spread. Invasive cancer stem cells (CSC) are considered to be the seed of GC metastasis and not all CSCs are able to initiate metastasis. Targeting these aggressive metastasis-initiating CSC (MIC) is thus vital. Leukaemia inhibitory factor (LIF) is hereby used to target Hippo pathway oncogenic members, found to be induced in GC and associated with CSC features. LIF-treated GC cell lines, patient-derived xenograft (PDX) cells and/or CSC tumourspheres underwent transcriptomics, laser microdissection-associated proteomics, 2D and 3D invasion assays and in vivo xenograft in mice blood circulation. LIFR expression was analysed on tissue microarrays from GC patients and in silico from public databases. LIF-treated cells, especially CSC, presented decreased epithelial to mesenchymal transition (EMT) phenotype and invasion capacity in vitro, and lower metastasis initiation ability in vivo. These effects involved both the Hippo and Jak/Stat pathways. Finally, GC's high LIFR expression was associated with better clinical outcomes in patients. LIF treatment could thus represent a targeted anti-CSC strategy to fight against metastatic GC, and LIFR detection in primary tumours could constitute a potential new prognosis marker in this disease.

The "StemDif Sensor Test": A Straightforward, Non-Invasive Assay to Characterize the Secreted Stemness and/or Differentiation Activities of Tumor-Derived Cancer Cell Lines

Cancer stem cells are a subpopulation of tumor cells characterized by their ability to self-renew, induce tumors upon engraftment in animals and exhibit strong resistance to chemotherapy and radiotherapy. These cells exhibit numerous characteristics in common with embryonic stem cells, expressing some of their markers, typically absent in non-pathological adult differentiated cells. The aim of this study was to investigate the potential of conditioned media from cancer stem cells to modulate the fate of Leukemia Inhibitory Factor (LIF)-dependent murine embryonic stem cells (mESCs) as a way to obtain a direct readout of the secretome of cancer cells. A functional assay, "the StemDif sensor test", was developed with two types of cancer stem cells derived from grade IV glioblastoma (adult and pediatric) or from gastric adenocarcinoma. We show that conditioned media from the selection of adult but not pediatric Glioma-Inducing Cells (GICs) maintain mESCs' pluripotency in correlation with LIF secretion and activation of STAT3 protein. In contrast, conditioned media from gastric adenocarcinoma cells display LIF-independent stemness and differentiation activities on mESC. Our test stands out for its user-friendly procedures, affordability and straightforward output, positioning it as a pioneering tool for in-depth exploration of cancer stem cell secretome characteristics.

Discovery of BAR502, as potent steroidal antagonist of leukemia inhibitory factor receptor for the treatment of pancreatic adenocarcinoma

Introduction

The leukemia inhibitory factor (LIF), is a cytokine belonging to IL-6 family, whose overexpression correlate with poor prognosis in cancer patients, including pancreatic ductal adenocarcinoma (PDAC). LIF signaling is mediate by its binding to the heterodimeric LIF receptor (LIFR) complex formed by the LIFR receptor and Gp130, leading to JAK1/STAT3 activation. Bile acids are steroid that modulates the expression/activity of membrane and nuclear receptors, including the Farnesoid-X-Receptor (FXR) and G Protein Bile Acid Activated Receptor (GPBAR1).

Methods

Herein we have investigated whether ligands to FXR and GPBAR1 modulate LIF/LIFR pathway in PDAC cells and whether these receptors are expressed in human neoplastic tissues.

Results

The transcriptome analysis of a cohort of PDCA patients revealed that expression of LIF and LIFR is increased in the neoplastic tissue in comparison to paired non-neoplastic tissues. By in vitro assay we found that both primary and secondary bile acids exert a weak antagonistic effect on LIF/LIFR signaling. In contrast, BAR502 a non-bile acid steroidal dual FXR and GPBAR1 ligand, potently inhibits binding of LIF to LIFR with an IC50 of 3.8 µM.

Discussion

BAR502 reverses the pattern LIF-induced in a FXR and GPBAR1 independent manner, suggesting a potential role for BAR502 in the treatment of LIFR overexpressing-PDAC.

Landscape of MicroRNA Regulatory Network Architecture and Functional Rerouting in Cancer

Somatic mutations are a major source of cancer development, and many driver mutations have been identified in protein coding regions. However, the function of mutations located in miRNA and their target binding sites throughout the human genome remains largely unknown. Here, we built detailed cancer-specific miRNA regulatory networks across 30 cancer types to systematically analyze the effect of mutations in miRNAs and their target sites in 3' untranslated region (3' UTR), coding sequence (CDS), and 5' UTR regions. A total of 3,518,261 mutations from 9,819 samples were mapped to miRNA-gene interactions (mGI). Mutations in miRNAs showed a mutually exclusive pattern with mutations in their target genes in almost all cancer types. A linear regression method identified 148 candidate driver mutations that can significantly perturb miRNA regulatory networks. Driver mutations in 3'UTRs played their roles by altering RNA binding energy and the expression of target genes. Finally, mutated driver gene targets in 3' UTRs were significantly downregulated in cancer and functioned as tumor suppressors during cancer progression, suggesting potential miRNA candidates with significant clinical implications. A user-friendly, open-access web portal (mGI-map) was developed to facilitate further use of this data resource. Together, these results will facilitate novel noncoding biomarker identification and therapeutic drug design targeting the miRNA regulatory networks.

SIGNIFICANCE

A detailed miRNA-gene interaction map reveals extensive miRNA-mediated gene regulatory networks with mutation-induced perturbations across multiple cancers, serving as a resource for noncoding biomarker discovery and drug development.

Repositioning Mifepristone as a Leukaemia Inhibitory Factor Receptor Antagonist for the Treatment of Pancreatic Adenocarcinoma

Pancreatic cancer is a leading cause of cancer mortality and is projected to become the second-most common cause of cancer mortality in the next decade. While gene-wide association studies and next generation sequencing analyses have identified molecular patterns and transcriptome profiles with prognostic relevance, therapeutic opportunities remain limited. Among the genes that are upregulated in pancreatic ductal adenocarcinomas (PDAC), the leukaemia inhibitory factor (LIF), a cytokine belonging to IL-6 family, has emerged as potential therapeutic candidate. LIF is aberrantly secreted by tumour cells and promotes tumour progression in pancreatic and other solid tumours through aberrant activation of the LIF receptor (LIFR) and downstream signalling that involves the JAK1/STAT3 pathway. Since there are no LIFR antagonists available for clinical use, we developed an in silico strategy to identify potential LIFR antagonists and drug repositioning with regard to LIFR antagonists. The results of these studies allowed the identification of mifepristone, a progesterone/glucocorticoid antagonist, clinically used in medical abortion, as a potent LIFR antagonist. Computational studies revealed that mifepristone binding partially overlapped the LIFR binding site. LIF and LIFR are expressed by human PDAC tissues and PDAC cell lines, including MIA-PaCa-2 and PANC-1 cells. Exposure of these cell lines to mifepristone reverses cell proliferation, migration and epithelial mesenchymal transition induced by LIF in a concentration-dependent manner. Mifepristone inhibits LIFR signalling and reverses STAT3 phosphorylation induced by LIF. Together, these data support the repositioning of mifepristone as a potential therapeutic agent in the treatment of PDAC.

LncRNA GAS5 Suppresses Colorectal Cancer Progress by Target miR-21/LIFR Axis

GAS5 is abnormally high in colorectal cancer tissues, which is a specific expression of lncRNA in colorectal cancer (CRC). Nevertheless, its biological function in CRC has not been elucidated. The abnormal high expression of GAS5 in CRC is the specific expression of lncRNA in CRC. The purpose of our study is to explore the effect of GAS5 on CRC and its mechanism. The expression of GAS5 in 53 paired normal and colorectal cancer tissues and colorectal cancer cell lines was detected by real-time PCR. The biological effects of GAS5, miR-21, and LIFR were measured by functional assays, including wound healing, transwell assays, and in vivo assays. We ensured the carcinogenesis role of GAS5 in CRC in the xenograft nude model. The dual-luciferase reporter assay system and chromatin immunoprecipitation method were used for target evaluation and Western blot for verification. GAS5 was significantly decreased in tumor tissues and CRC cells, and the low expression of CAS5 in CRC promoted tumor metastasis and decreased the survival of patients. GAS5 knockdown increases the cell viability, inhibits apoptosis, and promotes migration. Xenografted tumors in nude mice studies showed that GAS5 knockdown promoted tumor growth and caused worse lesions in colorectal. Furthermore, GAS5 increases the expression level of target gene LIFR to promote the apoptosis of CRC cells by binding to miR-21. Our study revealed that a novel pathway about lncRNA GAS5 inhibited the proliferation and metastasis of CRC cells by targeting miR-21/LIFR which provides a new strategy to treat CRC.

The Pleiotropic role, functions and targeted therapies of LIF/LIFR axis in cancer: Old spectacles with new insights

The dysregulation of leukemia inhibitory factor (LIF) and its cognate receptor (LIFR) has been associated with multiple cancer initiation, progression, and metastasis. LIF plays a significant tumor-promoting role in cancer, while LIFR functions as a tumor promoter and suppressor. Epithelial and stromal cells secrete LIF via autocrine and paracrine signaling mechanism(s) that bind with LIFR and subsequently with co-receptor glycoprotein 130 (gp130) to activate JAK/STAT1/3, PI3K/AKT, mTORC1/p70s6K, Hippo/YAP, and MAPK signaling pathways. Clinically, activating the LIF/LIFR axis is associated with poor survival and anti-cancer therapy resistance. This review article provides an overview of the structure and ligands of LIFR, LIF/LIFR signaling in developmental biology, stem cells, cancer stem cells, genetics and epigenetics of LIFR, LIFR regulation by long non-coding RNAs and miRNAs, and LIF/LIFR signaling in cancers. Finally, neutralizing antibodies and small molecule inhibitors preferentially blocking LIF interaction with LIFR and antagonists against LIFR under pre-clinical and early-phase pre-clinical trials were discussed.

Lidocaine Suppresses Gastric Cancer Development Through Circ_ANO5/miR-21-5p/LIFR Axis

BACKGROUND

Lidocaine has been manifested to exert anti-tumor role in gastric cancer (GC) progression. However, the action mechanism by which Lidocaine functions in GC has not been fully elucidated.

AIM

The study aimed to reveal the molecular mechanism of Lidocaine in GC progression.

METHODS

Cell clonogenicity and viability were assessed by colony formation and methyl thiazolyl tetrazolium assays, respectively. Transwell assay was employed to detect cell migration and invasion. Flow cytometry was implemented to monitor cell apoptosis. Relative expression of circular RNA ANO5 (circ_ANO5), microRNA (miR)-21-5p and Leukemia inhibitory factor receptor (LIFR) was examined by quantitative reverse transcription-polymerase chain reaction. Western blot assay was performed to analyze the levels of LIFR and cell metastasis-related proteins. The target relationship between miR-21-5p and circ_ANO5 or LIFR was confirmed by dual-luciferase reporter assay. In addition, xenograft model was established to explore the role of Lidocaine in vivo.

RESULTS

Lidocaine inhibited cell proliferation, migration and invasion, while promoted apoptosis of GC cells. Lidocaine upregulated circ_ANO5 and LIFR expression, but downregulated miR-21-5p expression in GC cells. Additionally, expression of circ_ANO5 and LIFR was decreased, while miR-21-5p expression was increased in GC cells. Circ_ANO5 depletion or miR-21-5p overexpression attenuated Lidocaine-induced anti-proliferative and anti-metastatic effects on GC cells. Circ_ANO5 could sponge miR-21-5p, and miR-21-5p targeted LIFR. Moreover, Lidocaine suppressed the tumor growth in vivo.

CONCLUSION

Lidocaine might GC cell malignancy by modulating circ_ANO5/miR-21-5p/LIFR axis, highlighting a novel insight for GC treatment.

Leukaemia inhibitory factor in gastric cancer: friend or foe?

IL-6 family cytokine leukaemia inhibitory factor (LIF) study has deciphered a variety of effects, in physiology as well as pathology. Despite the sudden arousal in LIF interest in cancers, its study in the gastric cancer (GC) context has been put aside. Only few related studies can be found in literature, most of them investigating IL-6/STAT3 signalling in GC, and not the particular LIF/LIFRβ signalisation. LIF/LIFR has opposing effects depending on the signalling pathways involved. This review relates the pro- and anti-tumorigenic aspects of LIF/LIFR in GC, taking also into account facts from other types of cancer. A better understanding of these issues would undoubtedly help postulate interesting hypotheses and perspectives for future LIF/LIFR study and its use in GC therapies, where options tend to be limited in number and efficiency.

Leukemia Inhibitory Factor: An Important Cytokine in Pathologies and Cancer

Leukemia Inhibitory Factor (LIF) is a member of the IL-6 cytokine family and is expressed in almost every tissue type within the body. Although LIF was named for its ability to induce differentiation of myeloid leukemia cells, studies of LIF in additional diseases and solid tumor types have shown that it has the potential to contribute to many other pathologies. Exploring the roles of LIF in normal physiology and non-cancer pathologies can give important insights into how it may be dysregulated within cancers, and the possible effects of this dysregulation. Within various cancer types, LIF expression has been linked to hallmarks of cancer, such as proliferation, metastasis, and chemoresistance, as well as overall patient survival. The mechanisms behind these effects of LIF are not well understood and can differ between different tissue types. In fact, research has shown that while LIF may promote malignancy progression in some solid tumors, it can have anti-neoplastic effects in others. This review will summarize current knowledge of how LIF expression impacts cellular function and dysfunction to help reveal new adjuvant treatment options for cancer patients, while also revealing potential adverse effects of treatments targeting LIF signaling.

miR-221-3p regulates hepatocellular carcinoma cell proliferation, migration and invasion via targeting LIFR

INTRODUCTION AND OBJECTIVES

Hepatocellular carcinoma (HCC) is one of the most common and fatal cancers in the world. This study aims to investigate the mechanism by which miR-221-3p regulates HCC cell proliferation, migration and invasion, so as to provide a new idea for targeted therapy towards HCC.

MATERIALS AND METHODS

Expression quantification data including mature miRNA and mRNA were accessed from TCGA-LIHC dataset, and matched clinical information was obtained as well, which helped identify the miRNA of interest. Thereafter, effect of the miRNA on HCC cell biological functions was assessed with a series of in vitro experiments, such as qRT-PCR, MTT, wound healing assay and Transwell. To gain more insight into the mechanism of the miRNA in HCC, bioinformatics method was conducted to predict downstream target gene. The potential targeting relationship between the miRNA and the predicted mRNA was validated by dual-luciferase reporter assay. Western blot was performed to test protein expression.

RESULTS

MiR-221-3p identified by differential expression analysis was found to be significantly elevated in HCC tissue. Overexpressing miR-221-3p noticeably enhanced HCC cell proliferative, migratory and invasive abilities. Leukemia inhibitory factor receptor (LIFR), confirmed as a downstream target of miR-221-3p in HCC by dual-luciferase reporter assay, was poorly expressed in HCC tissue and cells. Additionally, the expression of LIFR was decreased following the targeted binding between miR-221-3p and LIFR 3'-UTR, while increasing the expression of LIFR attenuated the promoting effect of miR-221-3p on HCC cells.

CONCLUSION

MiR-221-3p is an oncogene in HCC cells, and it exerts its role in HCC cell viability and motility via targeting LIFR.

Mutant KRAS Downregulates the Receptor for Leukemia Inhibitory Factor (LIF) to Enhance a Signature of Glycolysis in Pancreatic Cancer and Lung Cancer

Pancreatic cancer is characterized by aberrant activity of oncogenic KRAS, which is mutated in 90% of pancreatic adenocarcinomas. Because KRAS itself is a challenging therapeutic target, we focused on understanding key signaling pathways driven by KRAS as a way to reveal dependencies that are amenable to therapeutic intervention. Analyses in primary human pancreatic cancers and model systems revealed that the receptor for the cytokine leukemia inhibitory factor (LIF) is downregulated by mutant KRAS. Furthermore, downregulation of the LIF receptor (LIFR) is necessary for KRAS-mediated neoplastic transformation. We found LIFR exerts inhibitory effects on KRAS-mediated transformation by inhibiting expression of the glucose transporter GLUT1, a key mediator of the enhanced glycolysis found in KRAS-driven malignancies. Decreased LIFR expression leads to increased GLUT1 as well as increases in glycolysis and mitochondrial respiration. The repression of GLUT1 by LIFR is mediated by the transcription factor STAT3, indicating a tumor-suppressive role for STAT3 within cancer cells with mutated KRAS. Finally, reflecting a clinically important tumor-suppressive role of LIFR, decreased LIFR expression correlates with shorter survival in pancreatic cancer patients with mutated KRAS. Similar findings were found in non-small cell lung cancers driven by mutated KRAS, suggesting that silencing LIFR is a generalized mechanism of KRAS-mediated cellular transformation. These results indicate that the LIFR/STAT3 pathway may mediate either tumor-promoting or tumor-suppressive signaling pathways depending on the genetic background of tumor cells, and may play diverse roles within other cells in the tumor microenvironment. IMPLICATIONS: Mutant KRAS drives downregulation of the receptor for LIF, thereby allowing an increase in expression of the glucose transporter GLUT1 and increases in glycolysis and mitochondrial respiration.

Emerging Perspectives on Leukemia Inhibitory Factor and its Receptor in Cancer

Tumorigenesis and metastasis have deep connections to inflammation and inflammatory cytokines, but the mechanisms underlying these relationships are poorly understood. Leukemia Inhibitory Factor (LIF) and its receptor (LIFR), part of the interleukin-6 (IL-6) cytokine family, make up one such ill-defined piece of the puzzle connecting inflammation to cancer. Although other members of the IL-6 family have been shown to be involved in the metastasis of multiple types of cancer, the role of LIF and LIFR has been challenging to determine. Described by others in the past as enigmatic and paradoxical, LIF and LIFR are expressed in a diverse array of cells in the body, and the narrative surrounding them in cancer-related processes has been vague, and at times even contradictory. Despite this, recent insights into their functional roles in cancer have highlighted interesting patterns that may allude to a broader understanding of LIF and LIFR within tumor growth and metastasis. This review will discuss in depth the signaling pathways activated by LIF and LIFR specifically in the context of cancer–the purpose being to summarize recent literature concerning the downstream effects of LIF/LIFR signaling in a variety of cancer-related circumstances in an effort to begin teasing out the intricate web of contradictions that have made this pair so challenging to define.

Hsa_circ_0001073 targets miR-626/LIFR axis to inhibit lung cancer progression

Circular RNAs (circRNAs) are associated with lung cancer progression. However, it is unclear whether and how circRNA hsa_circ_0001073 (circ_0001073) are involved in lung cancer progression. circ_0001073, microRNA (miR)-626, and leukemia inhibitory factor receptor (LIFR) abundances were determined via quantitative reverse transcription polymerase chain reaction or western blot. Cell viability, invasion, and apoptosis were analyzed by cell counting kit-8, transwell analysis and flow cytometry, respectively. The target correlation was tested by dual-luciferase reporter analysis or RNA immunoprecipitation. Results showed that circ_0001073 abundance was down-regulated in lung cancer cells. circ_0001073 constrained cell viability and invasion and facilitated apoptosis in lung cancer cells. miR-626 was targeted via circ_0001073, and circ_0001073 inhibited lung cancer progression via reducing miR-626 expression. LIFR was targeted via miR-626, and miR-626 knockdown constrained cell viability and invasion and facilitated apoptosis in lung cancer cells via up-regulating LIFR. circ_0001073 increased LIFR expression via miR-626 in lung cancer cells. In conclusion, circ_0001073 represses lung cancer progression via miR-626/LIFR axis, indicating the potential value of circ_0001073 in lung cancer treatment.

Clinicopathological and prognostic significance of circRNAs in lung cancer: A systematic review and meta-analysis

BACKGROUND

Circular RNAs (circRNAs) regulate multiple pathways during lung cancer pathogenesis. Apart from functional significance, many circRNAs have been shown to be associated with clinicopathological characteristics and predict lung cancer prognosis. Our aim is to summarize the expanding knowledge of clinical roles of circRNAs in lung cancer.

METHODS

A thorough search of literature was conducted to identify articles about the correlation between circRNA expression and its prognostic and clinicopathological values. Biological mechanisms were summarized.

RESULTS

This study included 35 original articles and 32 circRNAs with prognostic roles for lung cancer. Increased expression of 25 circRNAs and decreased expression of 7 circRNAs predicted poor prognosis. For non-small cell lung cancer, changes of circRNAs were correlated with tumor size, lymph node metastasis, distant metastasis, tumor node metastasis (TNM) stage, and differentiation, indicating the major function of circRNAs is to promote lung cancer invasion and migration. Particularly, meta-analysis of ciRS-7, hsa_circ_0020123, hsa_circ_0067934 showed increase of the 3 circRNAs was associated with positive lymph node metastasis. Increase of ciRS-7 and hsa_circ_0067934 was also related with advanced TNM stage. The biological effects depend on the general function of circRNA as microRNA sponge.

CONCLUSIONS

CircRNAs have the potential to function as prognostic markers and are associated with lung cancer progression and metastasis.

Emerging roles for the IL-6 family of cytokines in pancreatic cancer

Pancreatic cancer has one of the poorest prognoses of all malignancies, with little improvement in clinical outcome over the past 40 years. Pancreatic ductal adenocarcinoma is responsible for the vast majority of pancreatic cancer cases, and is characterised by the presence of a dense stroma that impacts therapeutic efficacy and drives pro-tumorigenic programs. More specifically, the inflammatory nature of the tumour microenvironment is thought to underlie the loss of anti-tumour immunity and development of resistance to current treatments. Inflammatory pathways are largely mediated by the expression of, and signalling through, cytokines, chemokines, and other cellular messengers. In recent years, there has been much attention focused on dual targeting of cancer cells and the tumour microenvironment. Here we review our current understanding of the role of IL-6, and the broader IL-6 cytokine family, in pancreatic cancer, including their contribution to pancreatic inflammation and various roles in pancreatic cancer pathogenesis. We also summarise potential opportunities for therapeutic targeting of these pathways as an avenue towards combating poor patient outcomes.

Construction and Comprehensive Analysis of a ceRNA Network to Reveal Potential Novel Biomarkers for Triple-Negative Breast Cancer

Background

Triple-negative breast cancer (TNBC) is the most common and aggressive type of breast cancer with an unfavourable outcome worldwide. Novel therapeutic targets are urgently required to explore this malignancy. This study explored the ceRNA network and the important genes for predicting the therapeutic targets.

Methods

It identified the differentially expressed genes of mRNAs, lncRNAs and miRNAs between TNBC and non-TNBC samples in four cohorts (TCGA, GSE38959, GSE45827 and GSE65194) to explore the novel therapeutic targets for TNBC. Downstream analyses, including functional enrichment analysis, ceRNA network, protein–protein interaction and survival analysis, were then conducted by bioinformatics analysis. Finally, the potential core protein of the ceRNA network in TNBC was validated by immunohistochemistry.

Results

A total of 1,045 lncRNAs and 28 miRNAs were differentially expressed in the TCGA TNBC samples, and the intersections of 282 mRNAs (176 upregulations and 106 downregulations) between the GEO and TCGA databases were identified. A ceRNA network composed of 7 lncRNAs, 62 mRNAs, 12 miRNAs and 244 edges specific to TNBC was established. The functional assay showed dysregulated genes, and GO, DO and KEGG enrichment analysis were performed. Survival analysis showed that mRNA LIFR and lncRNA AC124312.3 were significantly correlated with the overall survival of patients with TNBC in the TCGA databases (P < 0.05). Finally, the LIFR protein was validated, and immunohistochemical results showed the upregulated expression of LIFR in TNBC tissues.

Conclusion

Thus, our study presents an enhanced understanding of the ceRNA network in TNBC, where the key gene LIFR may be a new promising potential therapeutic target for patients with TNBC.

Leukaemia Inhibitory Factor (LIF) Inhibits Cancer Stem Cells Tumorigenic Properties through Hippo Kinases Activation in Gastric Cancer

Cancer stem cells (CSCs) present chemo-resistance mechanisms contributing to tumour maintenance and recurrence, making their targeting of utmost importance in gastric cancer (GC) therapy. The Hippo pathway has been implicated in gastric CSC properties and was shown to be regulated by leukaemia inhibitory factor receptor (LIFR) and its ligand LIF in breast cancer. This study aimed to determine LIF’s effect on CSC properties in GC cell lines and patient-derived xenograft (PDX) cells, which remains unexplored. LIF’s treatment effect on CSC markers expression and tumoursphere formation was evaluated. The Hippo kinase inhibitor XMU-MP-1 and/or the JAK1 inhibitor Ruxolitinib were used to determine Hippo and canonical JAK/STAT pathway involvement in gastric CSCs’ response to LIF. Results indicate that LIF decreased tumorigenic and chemo-resistant CSCs, in both GC cell lines and PDX cells. In addition, LIF increased activation of LATS1/2 Hippo kinases, thereby decreasing downstream YAP/TAZ nuclear accumulation and TEAD transcriptional activity. LIF’s anti-CSC effect was reversed by XMU-MP-1 but not by Ruxolitinib treatment, highlighting the opposite effects of these two pathways downstream LIFR. In conclusion, LIF displays anti-CSC properties in GC, through Hippo kinases activation, and could in fine constitute a new CSCs-targeting strategy to help decrease relapse cases and bad prognosis in GC.

Programing Assembling/Releasing Multifunctional miRNA Nanomedicine to Treat Prostate Cancer

MicroRNAs (miRNAs) therapy has shown to have great promise for the treatment of androgen-independent prostate cancer (AIPC) due to the low efficiency of hormonal therapy. However, instability of RNA and inefficiency of RNA therapy limit the use of miRNAs in the treatment of AIPC. Here, we report a pH/ATP-activated nanocomplexes for increasing cytosolic delivery of miR146a which can effectively inhibit the expression of epidermal growth factor receptor (EGFR) in AIPC. The nanocomplexes show identical suppressing effect in invasion, colony formation, migration ability, and growth of DU145 cells compared with Lipofectamine 2000 (lipo). But for in vivo experiments, the nanocomplexes vigorously suppress the growth of tumor volumes comparing to lipo group after five weeks' treatment. These results demonstrate the potential of the pH/ATP-activated nanocarriers for AIPC gene therapy.

Plasma proteomics of biomarkers for inflammation or cancer cannot predict relapse in chronic myeloid leukaemia patients stopping tyrosine kinase inhibitor therapy

Several studies have now shown that chronic myeloid leukaemia (CML) patients in deep molecular remission may discontinue tyrosine kinase inhibitor (TKI) treatment with a treatment free remission (TFR) rate of approximately 40-60 %. Some factors influencing the possibility of TFR have been described but better tools are needed for individual prediction of long-term TFR. Herein, two multiplex panels were utilised to analyse a total of 162 different plasma proteins from 56 patients included in the TKI stopping trial EURO-SKI (Saussele et al., 2018). The purpose was to identify possible plasma protein markers for prediction of successful TKI discontinuation and to evaluate effects of TKI discontinuation on plasma protein profiles. No protein biomarkers sampled before TKI discontinuation could separate relapse cases from non-relapse cases but some plasma proteins differed between patients who relapsed and those who remained in TFR when followed over time after TKI cessation. In conclusion, the plasma protein markers in this study could not predict relapse after TKI discontinuation but may be of use to understand the mechanisms involved in maintenance of TFR.

Prognostic value of leukemia inhibitory factor and its receptor in pancreatic adenocarcinoma

Currently, the prognostic effects of leukemia inhibitory factor (LIF) and LIF receptor (LIFR) in pancreatic adenocarcinoma (PAAD) are not clear. In the present study, we utilized the large datasets from four public databases to investigate the expression of LIF and LIFR and their clinical significance in PAAD. Eight cohorts containing 1278 cases with PAAD were identified and the analysis results suggested that LIF was highly expressed while LIFR was lowly expressed in PAAD tissues compared with adjacent or normal tissues. Kaplan-Meier plot curves and univariate and multivariate Cox proportional hazards regression analyses indicated high LIF expression was associated with shorter overall survival (adjusted hazard ratio = 1.641, 95% CI: 1.399-1.925, p < 0.001) whereas high LIFR expression was associated with longer overall survival (adjusted hazard ratio = 0.653, 95% CI: 0.517-0.826, p < 0.001).

Leukemia inhibitory factor: Recent advances and implications in biotechnology

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine with several functions in health and disease ranging from inflammation to cancer. LIF is also a potential target and/or therapeutic agent for diseases such as multiple sclerosis, stroke and even psychological disorders, where the function of LIF as a neurotrophic factor has only recently been explored. In recent years, a limited number of LIF clinical trials have been completed, which partially explains the shortage of effective applications as a therapeutic agent. With the increasing interest from biotechnology companies producing recombinant LIF, this status quo will certainly change, and the potential impact of LIF in terms of disease diagnosis, treatment and management will be realized.

Mutation, methylation and expression analysis of LIFR gene in Indian breast cancer patients

LIFR functions as a tumor suppressor and metastatic suppressor of breast cancer. The present study investigates the status of LIFR gene in Indian breast cancer patients. A total of 137 breast cancer tissue and 137 adjacent normal tissue which served as controls were analyzed for mutation by automated DNA sequencing, methylation through methylation-specific polymerase chain reaction and its corresponding expression at mRNA and protein level using real-time quantitative polymerase chain reaction and immunohistochemistry respectively in Indian breast cancer patients. All the molecular findings were statistically correlated with clinopathological parameters of the patients to identify its association. LIFR mRNA expression was found to be 2.534 ± 3.52 fold downregulated with subsequent absence of protein in 67.15% cases (92/137). The absence of LIFR protein coincided with 80.95% (85/105) methylated cases thereby showing a very strong correlation among the LIFR promoter methylation and LIFR protein expression (p = 0.0001). We also observed G2968C nucleotide change in 6/137 cases of exon 20 of LIFR gene resulting in Glu990Gln mutation. Correlation of LIFR promoter methylation with geographic location and age at menopause and LIFR mutation with age at menarche, age at first live birth, molecular subtypes of breast cancer, and lymph node status remained significant even after bonferroni correction (p ≤ 0.0027). All these data suggests the relevance of these associations in relation to Indian breast cancer patients. The loss of LIFR protein was frequently found in Indian breast cancer patients, and aberrant promoter methylation showed a significant correlation with its downregulation.

TGFβ promotes breast cancer stem cell self-renewal through an ILEI/LIFR signaling axis

FAM3C/Interleukin-like EMT Inducer (ILEI) is an oncogenic member of the FAM3 cytokine family and serves essential roles in both epithelial-mesenchymal transition (EMT) and breast cancer metastasis. ILEI expression levels are regulated through a non-canonical TGFβ signaling pathway by 3’-UTR-mediated translational silencing at the mRNA level by hnRNP E1. TGFβ stimulation or silencing of hnRNP E1 increases ILEI translation and induces an EMT program that correlates to enhanced invasion and migration. Recently, EMT has been linked to the formation of breast cancer stem cells (BCSCs) that confer both tumor cell heterogeneity as well as chemoresistant properties. Herein, we demonstrate that hnRNP E1 knockdown significantly shifts normal mammary epithelial cells to mesenchymal BCSCs in vitro and in vivo. We further validate that modulating ILEI protein levels results in the abrogation of these phenotypes, promoting further investigation into the unknown mechanism of ILEI signaling that drives tumor progression. We identify LIFR as the receptor for ILEI, which mediates signaling through STAT3 to drive both EMT and BCSC formation. Reduction of either ILEI or LIFR protein levels results in reduced tumor growth, fewer tumor initiating cells and reduced metastasis within the hnRNP E1 knock-down cell populations in vivo. These results reveal a novel ligand-receptor complex that drives the formation of BCSCs and represents a unique target for the development of metastatic breast cancer therapies.

Apatinib-induced protective autophagy and apoptosis through the AKT-mTOR pathway in anaplastic thyroid cancer

Apatinib, an inhibitor of vascular endothelial growth factor receptor-2, has been shown to promote anti-cancer action across a wide range of malignancies, including gastric, lung, and breast cancers. Our previous study showed that apatinib increases apoptosis in anaplastic thyroid carcinoma (ATC), but the direct functional mechanism of tumor lethality mediated by apatinib is still unknown. In this study, we demonstrated that apatinib induced both autophagy and apoptosis in human ATC cells through downregulation of p-AKT and p-mTOR signals via the AKT/mTOR pathway. Moreover, inhibition of apatinib-induced autophagy increased apatinib-induced apoptosis in ATC cells, and additional tumor suppression was critically produced by the combination of apatinib and the autophagy inhibitor chloroquine in vivo and in vitro. These findings showed that both autophagy and AKT/mTOR signals were engaged in ATC cell death evoked by apatinib. ATC patients might benefit from the new anti-cancer drug, and molecular targeted treatment in combination with autophagy inhibitors shows promise as a treatment improvement.

Leukaemia inhibitory factor is associated with treatment resistance in oesophageal adenocarcinoma

Oesophageal cancer is an aggressive disease with a poor 5 year survival rate of <20% of diagnosed patients. Unfortunately, only 20-30% Oesophageal Adenocarinoma (OAC) patients show a beneficial response to neoadjuvant therapy (neoCT). Inflammation influences OAC given the increased risk of cancer development and poor outcome for obese patients where altered secretion of adipokines and cytokines from adipose tissue contributes a pro-tumourigenic environment. We carried out a large proteomics screen of 184 proteins to compare the inflammatory and oncogenic profiles of an isogenic radioresistant in-vitro model of OAC. We found that leukaemia inhibitory factor (LIF), an IL-6 type cytokine, was significantly elevated in radioresistant OAC cells (p=0.007). Furthermore, significantly higher circulating levels of LIF were present in the serum from treatment-naive OAC patients who had a subsequent poor pathological response to neo-adjuvant therapy, (p=0.037). Quantitative PCR analysis revealed expression of LIF receptor (LIFR) may function as a predictive indicator of response to neo-adjuvant chemoradiation therapy in OAC. LIF was demonstrated to be actively secreted from human OAC treatment-naïve biopsies and significantly correlated with the secretion of bFGF, VEGF-A and IL-8 (p<0.05, R=1), (p<0.05, R=0.9429), and (p<0.05, R=1) respectively. Importantly, LIF secretion negatively correlated with tumour infiltrating lymphocytes in pre-treatment OAC patient biopsies, (r=-0.8783, p=0.033). Elevated circulating LIF is a marker of poor response to neo-adjuvant treatment in OAC and secretion of this chemokine from the tumour is tightly linked with pro-tumourigenic mediators including bFGF, VEGF-A and IL-8. Targeting this pathway may be a novel mechanism enhance neoadjuvant treatment responses in OAC.

Identification of differentially expressed genes in cervical cancer by bioinformatics analysis

Cervical cancer is the most common gynecological malignancy. In recent years, the incidence of cervical cancer has had a younger trend. Cervical cancer morbidity and mortality rates have been significantly reduced due to recent decades of cervical cytology screening leading to the early detection and treatment of cervical cancer and precancerous lesions. There are a number of methods used to treat cervical cancer and improve the survival rate. However, the prevalence and recurrence rates of cervical cancer are increasing every year. There is an urgent requirement for a better understanding of the molecular mechanism cervical cancer development. The present study used scientific information retrieval from the Gene Expression Omnibus database to download the GSE26511 dataset, which contained 39 samples, including 19 cervical cancer lymph node-positive samples and 20 cervical cancer lymph node-negative samples. Using Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes analysis, and weighted gene co-expression network analysis, 1,263 differentially expressed genes were found that affected the biological processes, including 'cell cycle process', 'signaling pathways', 'immune response', 'cell activation', 'regulation of immune system process' and 'inflammatory response'. These areas should be the focus of study for cervical cancer in the future.

LIFR promotes tumor angiogenesis by up-regulating IL-8 levels in colorectal cancer

Leukemia inhibitory factor receptor (LIFR) has been documented as a cancer promoter and to be present at high levels in various types of tumor tissues. In our search for molecules prognostic of colorectal cancer (CRC), we found high levels of LIFR in CRC tissue samples. Further analyses revealed that LIFR was indeed prognostic of CRC patient survival, and was associated with tumor size, lymphatic metastasis and stages. LIFR was found to promote tumor growth, metastasis and angiogenesis both in vitro and in vivo. High levels of LIFR in CRC facilitated proliferation and migration of endothelial cells, resulting in an increase in angiogenic activity. Moreover, interleukin 8 (IL-8) was found to play a role in the LIFR induced angiogenesis. IL-8 levels were correlated with LIFR levels in CRC tissues, whereas depletion of IL-8 led to a reduced angiogenic activity of LIFR in CRC cells. In addition, LIFR increased phosphorylation level of Erk, which regulates il-8 transcription. We conclude that LIFR is possibly a valuable prognostic marker for CRC. Our results also implicate a mechanism by which LIFR regulates tumor angiogenesis through Erk/IL-8 pathway, and that LIFR could be a potential therapeutic target for CRC.

Long non-coding RNA-CTD-2108O9.1 represses breast cancer metastasis by influencing leukemia inhibitory factor receptor

Breast cancer (BC) is an aggressive malignant disease in women worldwide with a high tendency to metastasize. However, important biomarkers for BC metastasis remain largely undefined. In the present study, we identified that long non-coding RNA-CTD-2108O9.1 is downregulated in BC tissues and cells and acts as a metastatic inhibitor of BC. Mechanistic investigation determined that lncRNA-CTD-2108O9.1 represses metastasis by targeting leukemia inhibitory factor receptor (LIFR), which is designated as a metastasis suppressor in BC. Our study characterizes a significant tumor suppressor active in BC metastasis repression through the known metastasis inhibitor LIFR.

CQ sensitizes human pancreatic cancer cells to gemcitabine through the lysosomal apoptotic pathway via reactive oxygen species

As an established anticancer drug, gemcitabine (GEM) is an effective systemic treatment for advanced pancreatic cancer (PC). However, little is known about the potential effectors that may modify tumour cell sensitivity towards GEM. Autophagy, as a physiological cellular mechanism, is involved in both cell survival and cell death. In this study, we found that exposure to GEM induced a significant increase in autophagy in a dose-dependent manner in PANC-1 and BxPC-3 cells. Inhibition of autophagy by chloroquine (CQ) and ATG7 siRNA increased GEM-induced cytotoxicity, and CQ was more effective than ATG7 siRNA. Moreover, CQ significantly enhanced GEM-induced apoptosis, while ATG7 siRNA failed to show the similar effect. Subsequently, we identified a potential mechanism of this cooperative interaction by showing that GEM with CQ pretreatment markedly triggered reactive oxygen species (ROS) boost and then increased lysosomal membrane permeability. Consequently, cathepsins released from lysosome into the cytoplasm induced apoptosis. We showed that CQ could enhance PC cells response to GEM in xenograft models. In conclusion, our data showed that CQ sensitized PC cells to GEM through the lysosomal apoptotic pathway via ROS. Thus, CQ as a potential adjuvant to GEM might represent an attractive therapeutic strategy for PC treatment.

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin inhibits pancreatic cancer cell proliferation and induces apoptosis via the EGFR pathway and caspase signaling

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA) has demonstrated efficacy against several solid tumors. In this study, we found that PA-MSHA inhibited the proliferation of PANC-1 and SW1990 pancreatic cancer cells, but had no obvious effects on HPDE6-C7 normal human pancreatic duct epithelial cells. Electron microscopy revealed the presence of apoptotic bodies and intracellular vacuole formation in PA-MSHA-treated pancreatic cancer cells. Flow cytometric analysis indicated the rate of apoptosis correlated with the PA-MSHA concentration. We observed a decrease in cell fractions in G0/G1 and G2/M phases, and an increase in the fraction in S phase (p < 0.01). PA-MSHA thus caused cell cycle arrest. Increasing concentrations of PA-MSHA did not alter total levels of EGFR, AKT or ERK, but levels of the corresponding phosphoproteins decreased. PA-MSHA also reduced tumor volume in a xenograft mouse model of pancreatic cancer (p < 0.01). Furthermore, caspase-3 levels decreased while the levels of cleaved caspase-3 increased (p < 0.01). These data suggest that by blocking cell cycle progression, PA-MSHA induces apoptosis and inhibits tumor growth. PA-MSHA-mediated inhibition of EGFR signaling and activation of the caspase pathway may play an important role in the induction of apoptosis in pancreatic cancer cells.

Up-regulation of chemokine receptor CCR4 is associated with Human Hepatocellular Carcinoma malignant behavior

Studies indicate that the chemokine receptor is responsible for poor prognosis of hepatocellular carcinoma (HCC) patients. In this study, we initially demonstrated that CCR4 is overexpressed in HCC specimens, and its elevation in HCC tissues positively correlates with tumor capsule breakthrough and vascular invasion. Although overexpression of CCR4 failed to influent proliferation of HCC cells in vitro apparently, the prominent acceleration on HCC tumor growth in vivo was remarkable. The underlying mechanism may be involved in neovascularization. Interestingly, different from effect on proliferation, CCR4 overexpression could trigger HCC metastasis both in vitro and in vivo also induced HCC cell epithelial-mesenchymal transition (EMT) as well. Then we identified matrix metalloproteinase 2 (MMP2) as a direct target of CCR4 which plays an important role in CCR4-mediated HCC cell invasion, which was up-regulated by ERK/AKT signaling. Positive correlation between CCR4 and MMP2 expression was also observed in HCC tissues. In conclusion, our study suggested that chemokine receptor CCR4 promotes HCC malignancy and facilitated HCC cell metastases via ERK/AKT/MMP2 pathway. These findings suggest that CCR4 may be a potential new diagnostic and prognostic marker in HCC, and targeting CCR4 may be a potential therapeutic option for blocking HCC metastasis.

miR-629-3p may serve as a novel biomarker and potential therapeutic target for lung metastases of triple-negative breast cancer

Background

Different breast cancer subtypes show distinct tropisms for sites of metastasis. Notably, the lung is the most common site for the first distant recurrence in triple-negative breast cancer (TNBC). The identification of novel biomarkers for lung metastasis is of great importance to improving the outcome of TNBC. In this study, we sought to identify a microRNA (miRNA)-based biomarker and therapeutic target for lung metastasis of TNBC.

Methods

A total of 669 patients without de novo stage IV TNBC were recruited for this study. miRNA profiling was conducted in the discovery cohort. Diagnostic accuracy and prognostic values of candidate miRNAs were evaluated in the training and validation cohorts, respectively. The biological functions of candidate miRNAs, as well as potential targets, were further evaluated through bioinformatic analysis as well as by performing in vitro and in vivo assays.

Results

In the discovery set, we found that miR-629-3p was specifically upregulated in both metastatic foci (fold change 144.16, P < 0.0001) and primary tumors (fold change 74.37, P = 0.004) in patients with lung metastases. In the training set, the ROC curve showed that miR-629-3p yielded high diagnostic accuracy in discriminating patients with lung metastasis from patients without recurrence (AUC 0.865, 95% CI 0.800–0.930, P < 0.0001). Although miR-629-3p predicted poor overall survival and disease-free survival in the validation set, it failed to show significance after multivariate analysis. Notably, logistic regression analyses confirmed that miR-629-3p was an independent risk factor for lung metastasis (OR 4.1, 95% CI 2.5–6.6, P < 0.001). Inhibition of miR-629-3p drastically attenuated the viability and migration of TNBC cells, and it markedly suppressed lung metastasis in vivo. Furthermore, we identified the leukemia inhibitory factor receptor (LIFR), a well-known metastatic suppressive gene, to be a direct target of miR-629-3p.

Conclusions

miR-629-3p may serve as a novel biomarker and potential therapeutic target for lung metastases of TNBC mediated via LIFR.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0865-y) contains supplementary material, which is available to authorized users.