PIM1 is responsible for IL-6-induced breast cancer cell EMT and stemness via c-myc activation

NDRG1 and its Family Members: More than Just Metastasis Suppressor Proteins and Targets of Thiosemicarbazones

N-Myc downstream regulated gene-1 (NDRG1) and the other three members of this family (NDRG2, 3, and 4) play various functional roles in the cellular stress response, differentiation, migration, and development. These proteins are involved in regulating key signaling proteins and pathways that are often dysregulated in cancer, such as EGFR, PI3K/AKT, c-Met, and the Wnt pathway. NDRG1 is the primary, well-examined member of the NDRG family, and is generally characterized as a metastasis suppressor that inhibits the first step in metastasis, the epithelial-mesenchymal transition. While NDRG1 is well-studied, emerging evidence suggests NDRG2, NDRG3, and NDRG4 also play significant roles in modulating oncogenic signaling and cellular homeostasis. NDRG family members are regulated by multiple mechanisms, including transcriptional control by hypoxia-inducible factors, p53, and Myc, as well as post-translational modifications such as phosphorylation, ubiquitination, and acetylation. Pharmacological targeting of the NDRG family is a therapeutic strategy against cancer. For instance, di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT) and di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) have been extensively shown to up-regulate NDRG1 expression, leading to metastasis suppression and inhibition of tumor growth in multiple cancer models. Similarly, targeting NDRG2 demonstrates its pro-apoptotic and anti-proliferative effects, particularly in glioblastoma and colorectal cancer. This review provides a comprehensive analysis of the structural features, regulatory mechanisms, and biological functions of the NDRG family and their roles in cancer and neurodegenerative diseases. Additionally, NDRG1-4 are explored as therapeutic targets in oncology, focusing on recent advances in anti-cancer agents that induce the expression of these proteins. Implications for future research and clinical applications are also discussed.

Evaluation of the anti-leukemia activity and underlying mechanisms of the novel perinucleolar compartment inhibitor CTI-2 in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant clonal hematological tumor originating from immature myeloid cells and is the most prevalent type of leukemia in adults. Traditional chemotherapy regimens based on cytarabine and anthracycline agents are associated with a high relapse rate. Therefore, investigation of novel targeted therapies is crucial for improving AML treatment outcomes. In this study, we found that CTI-2, a novel inhibitor of perinucleolar compartment (PNC), has potential anti-AML activity with a favorable safety profile. CTI-2 induced a greater degree of apoptosis in FLT3-ITD mutant AML cells compared to AML cells with wild-type FLT3 mainly through the intrinsic apoptotic pathway. Furthermore, MK2 and Pim-1 were identified as potential targets of CTI-2 through molecular docking analysis. CTI-2 decreased both the overall expression level and the phosphorylation of c-Myc, which are regulated by MK2 and Pim-1, respectively. Notably, CTI-2 exhibited a more substantial inhibitory effect on c-Myc in FLT3-ITD mutant cells, which may contribute to the enhanced efficacy of CTI-2 in this specific subset of AML. In summary, we have conducted a preliminary investigation into the anti-AML activity and underlying mechanisms of CTI-2. These results provide clues for the targeting of PNC in the treatment of AML.

PIM1 kinase and its diverse substrate in solid tumors

The PIM kinase family, consisting of PIM1, PIM2, and PIM3, is a group of serine/threonine protein kinases crucial for cellular growth, immunoregulation, and oncogenesis. PIM1 kinase is often overexpressed in solid and hematopoietic malignancies, promoting cell survival, proliferation, migration, and senescence by activating key genes. In vitro and in vivo studies have established the oncogenic potential of PIM1 kinases. These kinases have been implicated in tumor progression, metastasis, and resistance to chemotherapy, underscoring their potential as a therapeutic target for cancer therapy. This review delves into the intricate molecular mechanisms through which PIM1 interacts with specific substrates in different tumor tissues, leading to diverse outcomes in various human cancers. Over the past decade, the inhibition of PIM1 in cancers has garnered significant attention as a potential standalone treatment. Various in vitro, in vivo, and early clinical trial data have provided support for this approach to varying extents. Novel compounds that inhibit PIM1 kinase have shown effectiveness and a favorable toxicity profile in preclinical studies. Several of these substances are now being studied in clinical trials due to their promising outcomes. This article provides a thorough examination of the PIM1 kinase pathways and the recent advancements in producing PIM1 kinase inhibitors for the treatment of cancer.

SALL2 regulates neural differentiation of mouse embryonic stem cells through Tuba1a

The spalt (Sal) gene family has four members (Sall1-4) in vertebrates, all of which play pivotal roles in various biological processes and diseases. However, the expression and function of SALL2 in development are still less clear. Here, we first charted SALL2 protein expression pattern during mouse embryo development by immunofluorescence, which revealed its dominant expression in the developing nervous system. With the establishment of Sall2 deficient mouse embryonic stem cells (ESCs), the in vitro neural differentiation system was leveraged to interrogate the function of SALL2, which showed impaired neural differentiation of Sall2 knockout (KO) ESCs. Furthermore, neural stem cells (NSCs) could not be derived from Sall2 KO ESCs and the generation of neural tube organoids (NTOs) was greatly inhibited in the absence of SALL2. Meanwhile, transgenic expression of E1 isoform of SALL2 restored the defects of neural differentiation in Sall2 KO ESCs. By chromatin immunoprecipitation sequencing (ChIP-seq), Tuba1a was identified as downstream target of SALL2, whose function in neural differentiation was confirmed by rescuing neural phenotypes of Sall2 KO ESCs when overexpressed. In sum, by elucidating SALL2 expression dynamics during early mouse development and mechanistically characterizing its indispensable role in neural differentiation, this study offers insights into SALL2's function in human nervous system development, associated pathologies stemming from its mutations and relevant therapeutic strategy.

PIM1 signaling in immunoinflammatory diseases: an emerging therapeutic target

PIM1, the proviral integration site for Moloney murine leukemia virus, is a member of the serine/threonine protein kinase family. It is involved in many biological events, such as cell survival, cell cycle progression, cell proliferation, and cell migration, and has been widely studied in malignant diseases. However, recent studies have shown that PIM1 plays a prominent role in immunoinflammatory diseases, including autoimmune uveitis, inflammatory bowel disease, asthma, and rheumatoid arthritis. PIM1 can function in inflammatory signal transduction by phosphorylating multiple inflammatory protein substrates and mediating macrophage activation and T lymphocyte cell specification, thus participating in the development of multiple immunoinflammatory diseases. Moreover, the inhibition of PIM1 has been demonstrated to ameliorate certain immunoinflammatory disorders. Based on these studies, we suggest PIM1 as a potential therapeutic target for immunoinflammatory diseases and a valid candidate for future research. Herein, for the first time, we provide a detailed review that focuses on the roles of PIM1 in the pathogenesis of immunoinflammatory diseases.

Targeting Molecular Signaling Pathways and Cytokine Responses to Modulate c-MYC in Acute Myeloid Leukemia

Overexpression of the MYC oncogene, encoding c-MYC protein, contributes to the pathogenesis and drug resistance of acute myeloid leukemia (AML) and many other hematopoietic malignancies. Although standard chemotherapy has predominated in AML therapy over the past five decades, the clinical outcomes and patient response to treatment remain suboptimal. Deeper insight into the molecular basis of this disease should facilitate the development of novel therapeutics targeting specific molecules and pathways that are dysregulated in AML, including fms-like tyrosine kinase 3 (FLT3) gene mutation and cluster of differentiation 33 (CD33) protein expression. Elevated expression of c-MYC is one of the molecular features of AML that determines the clinical prognosis in patients. Increased expression of c-MYC is also one of the cytogenetic characteristics of drug resistance in AML. However, direct targeting of c-MYC has been challenging due to its lack of binding sites for small molecules. In this review, we focused on the mechanisms involving the bromodomain and extra-terminal (BET) and cyclin-dependent kinase 9 (CDK9) proteins, phosphoinositide-Akt-mammalian target of rapamycin (PI3K/AKT/mTOR) and Janus kinase-signal transduction and activation of transcription (JAK/STAT) pathways, as well as various inflammatory cytokines, as an indirect means of regulating MYC overexpression in AML. Furthermore, we highlight Food and Drug Administration (FDA)-approved drugs for AML, and the results of preclinical and clinical studies on novel agents that have been or are currently being tested for efficacy and tolerability in AML therapy. Overall, this review summarizes our current knowledge of the molecular processes that promote leukemogenesis, as well as the various agents that intervene in specific pathways and directly or indirectly modulate c-MYC to disrupt AML pathogenesis and drug resistance.

PIM1 kinase promotes EMT-associated osimertinib resistance via regulating GSK3β signaling pathway in EGFR-mutant non-small cell lung cancer

Acquired resistance is inevitable in the treatment of non-small cell lung cancer (NSCLC) with osimertinib, and one of the primary mechanisms responsible for this resistance is the epithelial-mesenchymal transition (EMT). We identify upregulation of the proviral integration site for Moloney murine leukemia virus 1 (PIM1) and functional inactivation of glycogen synthase kinase 3β (GSK3β) as drivers of EMT-associated osimertinib resistance. Upregulation of PIM1 promotes the growth, invasion, and resistance of osimertinib-resistant cells and is significantly correlated with EMT molecules expression. Functionally, PIM1 suppresses the ubiquitin-proteasome degradation of snail family transcriptional repressor 1 (SNAIL) and snail family transcriptional repressor 2 (SLUG) by deactivating GSK3β through phosphorylation. The stability and accumulation of SNAIL and SLUG facilitate EMT and encourage osimertinib resistance. Furthermore, treatment with PIM1 inhibitors prevents EMT progression and re-sensitizes osimertinib-resistant NSCLC cells to osimertinib. PIM1/GSK3β signaling is activated in clinical samples of osimertinib-resistant NSCLC, and dual epidermal growth factor receptor (EGFR)/PIM1 blockade synergistically reverse osimertinib-resistant NSCLC in vivo. These data identify PIM1 as a driver of EMT-associated osimertinib-resistant NSCLC cells and predict that PIM1 inhibitors and osimertinib combination therapy will provide clinical benefit in patients with EGFR-mutant NSCLC.

PIM1 alleviated liver oxidative stress and NAFLD by regulating the NRF2/HO-1/NQO1 pathway

AIMS

Non-alcoholic fatty liver disease (NAFLD) has risen as a significant global public health issue, for which vertical sleeve gastrectomy (VSG) has become an effective treatment method. The study sought to elucidate the processes through which PIM1 mitigates the advancement of NAFLD. The Pro-viral integration site for Moloney murine leukemia virus 1 (PIM1) functions as a serine/threonine kinase. Bioinformatics analysis revealed that reduced PIM1 expression in NAFLD.

METHODS

To further prove the role of PIM1 in NAFLD, an in-depth in vivo experiment was performed, in which male C57BL/6 mice were randomly grouped to receive a normal or high-fat diet for 24 weeks. They were operated or delivered the loaded adeno-associated virus which the PIM1 was overexpressed (AAV-PIM1). In an in vitro experiment, AML12 cells were treated with palmitic acid to induce hepatic steatosis.

KEY FINDINGS

The results revealed that the VSG surgery and virus delivery of mice alleviated oxidative stress, and apoptosis in vivo. For AML12 cells, the levels of oxidative stress, apoptosis, and lipid metabolism were reduced via PIM1 upregulation. Moreover, ML385 treatment resulted in the downregulation of the NRF2/HO-1/NQO1 signaling cascade, indicating that PIM1 mitigates NAFLD by targeting this pathway.

SIGNIFICANCE

PIM1 alleviated mice liver oxidative stress and NAFLD induced by high-fat diet by regulating the NRF2/HO-1/NQO1 signaling Pathway.

Role of Fibrinogen-like Protein 1 in Tumor Recurrence Following Hepatectomy

Partial hepatectomy is a first-line treatment for hepatocellular carcinoma. Within 2 weeks following partial hepatectomy, specific molecular pathways are activated to promote liver regeneration. Nevertheless, residual microtumors may also exploit these pathways to reappear and metastasize. Therapeutically targeting molecules that are differentially regulated between normal cells and malignancies, such as fibrinogen-like protein 1 (FGL1), appears to be an effective approach. The potential functions of FGL1 in both regenerative and malignant cells are discussed within the ambit of this review. While FGL1 is normally elevated in regenerative hepatocytes, it is normally downregulated in malignant cells. Hepatectomy does indeed upregulate FGL1 by increasing the release of transcription factors that promote FGL1, including HNF-1α and STAT3, and inflammatory effectors, such as TGF-β and IL6. This, in turn, stimulates certain proliferative pathways, including EGFR/Src/ERK. Hepatectomy alters the phase transition of highly differentiated hepatocytes from G0 to G1, thereby transforming susceptible cells into cancerous ones. Activation of the PI3K/Akt/mTOR pathway by FGL1 allele loss on chromosome 8, a tumor suppressor area, may also cause hepatocellular carcinoma. Interestingly, FGL1 is specifically expressed in the liver via HNF-1α histone acetylase activity, which triggers lipid metabolic reprogramming in malignancies. FGL1 might also be involved in other carcinogenesis processes such as hypoxia, epithelial-mesenchymal transition, immunosuppression, and sorafenib-mediated drug resistance. This study highlights a research gap in these disciplines and the necessity for additional research on FGL1 function in the described processes.

Nano-enhanced immunotherapy: Targeting the immunosuppressive tumor microenvironment

The tumor microenvironment (TME), which is mostly composed of tumor cells, immune cells, signaling molecules, stromal tissue, and the vascular system, is an integrated system that is conducive to the formation of tumors. TME heterogeneity makes the response to immunotherapy different in different tumors, such as "immune-cold" and "immune-hot" tumors. Tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells are the major suppressive immune cells and their different phenotypes interact and influence cancer cells by secreting different signaling factors, thus playing a key role in the formation of the TME as well as in the initiation, growth, and metastasis of cancer cells. Nanotechnology development has facilitated overcoming the obstacles that limit the further development of conventional immunotherapy, such as toxic side effects and lack of targeting. In this review, we focus on the role of three major suppressive immune cells in the TME as well as in tumor development, clinical trials of different drugs targeting immune cells, and different attempts to combine drugs with nanomaterials. The aim is to reveal the relationship between immunotherapy, immunosuppressive TME and nanomedicine, thus laying the foundation for further development of immunotherapy.

Isolation of Viable Epithelial and Mesenchymal Circulating Tumor Cells from Breast Cancer Patients

Circulating tumor cells (CTCs) undergoing epithelial-mesenchymal transition (EMT) may exhibit more aggressive features than epithelial CTCs and are more frequently observed during disease progression. Therefore, detection and characterization of both epithelial and mesenchymal CTCs in cancer patients are urgently needed to allow for a better understanding of the metastatic process and more effective treatment. Here we describe a method for detection and isolation of viable epithelial and mesenchymal CTCs from peripheral blood of breast cancer patients. The method is based on density gradient centrifugation, multiplex immunofluorescent staining, and negative anti-CD45 selection. Cells obtained after the procedure are suitable for genomic or transcriptomic profiling, and they can also be isolated by micromanipulation for single-cell analysis.

Mutant PIK3CA as a negative predictive biomarker for treatment with a highly selective PIM1 inhibitor in human colon cancer

Significant improvement in targeted therapy for colorectal cancer (CRC) has occurred over the past few decades since the approval of the EGFR inhibitor cetuximab. However, cetuximab is used only for patients possessing the wild-type oncogene KRAS, NRAS, and BRAF, and even most of these eventually acquire therapeutic resistance, via activation of parallel oncogenic pathways such as RAS-MAPK or PI3K/Akt/mTOR. The two aforementioned pathways also contribute to the development of therapeutic resistance in CRC patients, due to compensatory and feedback mechanisms. Therefore, combination drug therapies (versus monotherapy) targeting these multiple pathways may be necessary for further efficacy against CRC. In this study, we identified PIK3CA mutant (PIK3CA MT) as a determinant of resistance to SMI-4a, a highly selective PIM1 kinase inhibitor, in CRC cell lines. In CRC cell lines, SMI-4a showed its effect only in PIK3CA wild type (PIK3CA WT) cell lines, while PIK3CA MT cells did not respond to SMI-4a in cell death assays. In vivo xenograft and PDX experiments confirmed that PIK3CA MT is responsible for the resistance to SMI-4a. Inhibition of PIK3CA MT by PI3K inhibitors restored SMI-4a sensitivity in PIK3CA MT CRC cell lines. Taken together, these results demonstrate that sensitivity to SMI-4a is determined by the PIK3CA genotype and that co-targeting of PI3K and PIM1 in PIK3CA MT CRC patients could be a promising and novel therapeutic approach for refractory CRC patients.

Possible cancer-causing capacity of COVID-19: Is SARS-CoV-2 an oncogenic agent?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown diverse life-threatening effects, most of which are considered short-term. In addition to its short-term effects, which has claimed many millions of lives since 2019, the long-term complications of this virus are still under investigation. Similar to many oncogenic viruses, it has been hypothesized that SARS-CoV-2 employs various strategies to cause cancer in different organs. These include leveraging the renin angiotensin system, altering tumor suppressing pathways by means of its nonstructural proteins, and triggering inflammatory cascades by enhancing cytokine production in the form of a "cytokine storm" paving the way for the emergence of cancer stem cells in target organs. Since infection with SARS-CoV-2 occurs in several organs either directly or indirectly, it is expected that cancer stem cells may develop in multiple organs. Thus, we have reviewed the impact of coronavirus disease 2019 (COVID-19) on the vulnerability and susceptibility of specific organs to cancer development. It is important to note that the cancer-related effects of SARS-CoV-2 proposed in this article are based on the ability of the virus and its proteins to cause cancer but that the long-term consequences of this infection will only be illustrated in the long run.

Role of c-Myc in lung cancer: Progress, challenges, and prospects

Lung cancer remains the leading cause of cancer-related deaths worldwide. Despite the recent advances in cancer therapies, the 5-year survival of non-small cell lung cancer (NSCLC) patients hovers around 20%. Inherent and acquired resistance to therapies (including radiation, chemotherapies, targeted drugs, and combination therapies) has become a significant obstacle in the successful treatment of NSCLC. c-Myc, one of the critical oncoproteins, has been shown to be heavily associated with the malignant cancer phenotype, including rapid proliferation, metastasis, and chemoresistance across multiple cancer types. The c-Myc proto-oncogene is amplified in small cell lung cancers (SCLCs) and overexpressed in over 50% of NSCLCs. c-Myc is known to actively regulate the transcription of cancer stemness genes that are recognized as major contributors to tumor progression and therapeutic resistance; thus, targeting c-Myc either directly or indirectly in mitigation of the cancer stemness phenotype becomes a promising approach for development of a new strategy against drug resistant lung cancers. This review will summarize what is currently known about the mechanisms underlying c-Myc regulation of cancer stemness and its involvement in drug resistance and offer an overview on the current progress and future prospects in therapeutically targeting c-Myc in both SCLC and NSCLC.

The Myc Family and the Metastasis Suppressor NDRG1: Targeting Key Molecular Interactions with Innovative Therapeutics

Cancer is a leading cause of death worldwide, resulting in ∼10 million deaths in 2020. Major oncogenic effectors are the Myc proto-oncogene family, which consists of three members including c-Myc, N-Myc, and L-Myc. As a pertinent example of the role of the Myc family in tumorigenesis, amplification of MYCN in childhood neuroblastoma strongly correlates with poor patient prognosis. Complexes between Myc oncoproteins and their partners such as hypoxia-inducible factor-1α and Myc-associated protein X (MAX) result in proliferation arrest and pro-proliferative effects, respectively. Interactions with other proteins are also important for N-Myc activity. For instance, the enhancer of zest homolog 2 (EZH2) binds directly to N-Myc to stabilize it by acting as a competitor against the ubiquitin ligase, SCFFBXW7, which prevents proteasomal degradation. Heat shock protein 90 may also be involved in N-Myc stabilization since it binds to EZH2 and prevents its degradation. N-Myc downstream-regulated gene 1 (NDRG1) is downregulated by N-Myc and participates in the regulation of cellular proliferation via associating with other proteins, such as glycogen synthase kinase-3β and low-density lipoprotein receptor-related protein 6. These molecular interactions provide a better understanding of the biologic roles of N-Myc and NDRG1, which can be potentially used as therapeutic targets. In addition to directly targeting these proteins, disrupting their key interactions may also be a promising strategy for anti-cancer drug development. This review examines the interactions between the Myc proteins and other molecules, with a special focus on the relationship between N-Myc and NDRG1 and possible therapeutic interventions. SIGNIFICANCE STATEMENT: Neuroblastoma is one of the most common childhood solid tumors, with a dismal five-year survival rate. This problem makes it imperative to discover new and more effective therapeutics. The molecular interactions between major oncogenic drivers of the Myc family and other key proteins; for example, the metastasis suppressor, NDRG1, may potentially be used as targets for anti-neuroblastoma drug development. In addition to directly targeting these proteins, disrupting their key molecular interactions may also be promising for drug discovery.

The prognostic significance of KLRB1 and its further association with immune cells in breast cancer

BACKGROUND

Killer cell lectin-like receptor B1 (KLRB1) is an important member of the natural killer cell gene family. This study explored the potential value of KLRB1 as a breast cancer (BC) biomarker and its close association with the tumor immune microenvironment during the development of BC.

METHODS

We examined the differential expression of KLRB1 in pan-cancer. Clinical and RNA-Seq data from BC samples were evaluated in The Cancer Genome Atlas (TCGA) and validated in Gene Expression Omnibus (GEO) datasets and by immunohistochemistry (IHC) staining. The relationship between KLRB1 and clinical parameters was explored through Chi-square tests. The diagnostic value of KLRB1 was evaluated using a receiver operating characteristic (ROC) curve. Survival analysis was tested by Kaplan-Meier curves to demonstrate the relationship between KLRB1 and survival. Univariable and multivariate cox regression analyses were carried out as well. The analysis of immune infiltration level and gene set enrichment analysis (GSEA) were conducted to examine KLRB1's mechanism during the progression of BC. We used the Tumor Immune Estimation Resource (TIMER), the Cancer Single-cell Expression Map (CancerSCEM) database, the Tumor Immune Single-cell Hub (TISCH) database, and the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) method to explore KLRB1's association with immune infiltration level and different quantitative distribution of immune cells. The relevant signaling pathways in BC associated with KLRB1 were identified using GSEA.

RESULTS

The expression of KLRB1 was downregulated across the majority of cancers including BC. The lower KLRB1 expression group exhibited shorter relapse free survival (RFS) and overall survival (OS). IHC staining showed that KLRB1 staining was weaker in breast tumor tissues than in paratumors. Additionally, GSEA identified several pathway items distinctly enriched in BC. KLRB1 expression level was also positively related to the infiltrating number of immune cells in BC. Moreover, the CancerSCEM and TISCH databases as well as the CIBERSORT method demonstrated the close relationship between KLRB1 and immune cells, particularly macrophages.

CONCLUSION

Low KLRB1 expression was considered an independent prognostic biomarker and played an important role in the tumor immune microenvironment of BC patients.

LPCAT1 functions as an oncogene in cervical cancer through mediating JAK2/STAT3 signaling

Cervical cancer is a major gynecological tumor worldwide. Unfortunately, the molecular mechanisms involved in cervical cancer tumorigenesis still requires more clarification. Lysophosphatidylcholine acyltransferase 1 (LPCAT1), an enzyme involved in phosphatidylcholine metabolism, has been reported to regulate the proliferation, epithelial-mesenchymal transition (EMT) and recurrence of malignancies. Here in our study, we found that LPAT1 was over-expressed in clinical cervical cancer tissues, and its high expression was closely correlated with poor outcomes of patients. We further showed that LPCAT1 knockdown remarkably restrained the proliferation, migration and invasion of cervical cancer cells, while it significantly induced apoptosis. RNA-seq and bioinformatics assays initially showed that interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) pathway was a key mechanism for LPCAT1 to regulate cervical cancer progression. LPCAT1 silence strongly decreased IL-6, p-Janus kinase 2 (JAK2) and p-STAT3 expression levels in cervical cancer cells. Similarly, the expression levels of IL-6/STAT3 target genes were also highly down-regulated in cervical cancer cells with LPCAT1 deletion. Importantly, we found that human recombinant IL-6 addition considerably abolished the function of LPCAT1-knockdown to suppress the proliferation and EMT process in cervical cancer cells, accompanied with mitigated apoptotic cell death. Furthermore, our animal experiment results validated that stable LPCAT1 deletion efficiently reduced the tumor growth rates of xenograft mouse models and lung metastasis in vivo. Collectively, all our findings revealed that LPCAT1 may be a promising alternative prognostic biomarker and therapeutic target for cervical cancer through regulating JAK2/STAT3 signaling pathway.

Chronic inflammation, cancer development and immunotherapy

Chronic inflammation plays a pivotal role in cancer development. Cancer cells interact with adjacent cellular components (pro-inflammatory cells, intrinsic immune cells, stromal cells, etc.) and non-cellular components to form the inflammatory tumor microenvironment (TME). Interleukin 6 (IL-6), macrophage migration inhibitory factor (MIF), immune checkpoint factors and other pro-inflammatory cytokines produced by intrinsic immune cells in TME are the main mediators of intercellular communication in TME, which link chronic inflammation to cancer by stimulating different oncogenic signaling pathways and improving immune escape to promote cancer development. In parallel, the ability of monocytes, T regulatory cells (Tregs) and B regulatory cells (Bregs) to perform homeostatic tolerogenic functions is hijacked by cancer cells, leading to local or systemic immunosuppression. Standard treatments for advanced malignancies such as chemotherapy and radiotherapy have improved in the last decades. However, clinical outcomes of certain malignant cancers are not satisfactory due to drug resistance and side effects. The clinical application of immune checkpoint therapy (ICT) has brought hope to cancer treatment, although therapeutic efficacy are still limited due to the immunosuppressive microenvironment. Emerging evidences reveal that ideal therapies including clearance of tumor cells, disruption of tumor-induced immunosuppression by targeting suppressive TME as well as reactivation of anti-tumor T cells by ICT. Here, we review the impacts of the major pro-inflammatory cells, mediators and their downstream signaling molecules in TME on cancer development. We also discuss the application of targeting important components in the TME in the clinical management of cancer.

Role of STAT3 in the initiation, progression, proliferation and metastasis of breast cancer and strategies to deliver JAK and STAT3 inhibitors

INTRODUCTION

Breast cancer (BC) accounts for the majority of cancers among the female population. Anomalous activation of various signaling pathways has become an issue of concern. The JAK-STAT signaling pathway is activated in numerous cancers, including BC. STAT3 is widely involved in BCs, as 40 % of BCs display phosphorylated STAT3. JAK-STAT signaling is crucial for proliferation, survival, metastasis and other cellular events associated with the tumor microenvironment. Hence, targeting this pathway has become an area of interest among researchers.

KEY FINDINGS

This review article focuses on the role of STAT3 in the initiation, proliferation, progression and metastasis of BC. The roles of various phytochemicals, synthetic molecules and biologicals against JAK-STAT and STAT3 in various cancers have been discussed, with special emphasis on BC.

SIGNIFICANCE

JAK and STAT3 are involved in various phases from initiation to metastasis, and targeting this pathway is a promising approach to inhibit the various stages of BC development and to prevent metastasis. A number of phytochemicals and synthetic and biological molecules have demonstrated potential inhibitory effects on JAK and STAT3, thereby paving the way for the development of better therapeutics against BC.

LncRNA HEIH/miR-4500/IGF2BP1/c-Myc Feedback Loop Accelerates Bladder Cancer Cell Growth and Stemness

BACKGROUND

Bladder cancer (BCa) is one of the most prevalent malignancies and more common in men. An aberrantly expressed long noncoding RNA (lncRNA) hepatocellular carcinoma up-regulated EZH2-associated lncRNA (HEIH) has been reported to be implicated in the progression of many cancers, but its role in BCa remains little known. Our study intended to uncover whether and how HEIH regulates BCa progression.

MATERIALS AND METHODS

Quantitative real-time polymerase chain reaction (RT-qPCR) was adopted to determine HEIH expression in BCa cell lines. Functional experiments were performed to examine the effects of HEIH on BCa cell proliferation, apoptosis, migration, invasion and stemness. Bioinformatics analysis and mechanism experiments were conducted to investigate the regulatory relationship between HEIH and related molecules in BCa.

RESULTS

HEIH expression was observed to be significantly increased in BCa cell lines. HEIH depletion significantly hindered BCa cell proliferation, migration and invasion. Besides, HEIH up-regulated MYC proto-oncogene, and bHLH transcription factor (c-Myc) expression to promote BCa cell stemness. Moreover, HEIH served as a sponge for miR-4500 to modulate insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) expression, thereby stabilizing c-Myc mRNA level.

CONCLUSION

Our study demonstrated a positive feedback loop of HEIH/miR-4500/IGF2BP1/c-Myc in BCa progression, offering a novel insight into a possible BCa therapy.

Clinical Significance of Pim-1 in Human Cancers: A Meta-analysis of Association with Prognosis and Clinicopathological Characteristics

Background

Pim-1 is overexpressed in cancer tissues and plays a vital role in carcinogenesis. However, its clinical significance in cancers is not fully verified by meta-analysis, especially in relation to prognosis and clinicopathological features.

Methods

Four databases, PubMed, Embase, Cochrane Library, and Web of Science, were searched. Literature screening and data extraction according to the inclusion and exclusion criteria. The quality of the included literatures was evaluated using the Newcastle-Ottawa scale and the data analysis was performed using STATA and Review Manager software.

Results

15 articles were finally included for meta-analysis, involving 1651 patients. Effect-size pooling analysis showed that high Pim-1 was related to poor overall survival (OS) (HR 1.68 [95% CI 1.17-2.40], P = .004) and disease-free survival (DFS) (HR 2.15 [95 %CI 1.15-4.01], P = .000). Subgroup analysis indicated that the detection techniques of Pim-1 were the main sources of heterogeneity, and 2 literatures using quantitative polymerase chain reaction (qPCR) for Pim-1mRNA had high homogeneity (I² = .0%, P = .321) in OS. Another 13 studies that applied immunohistochemistry (IHC) for Pim-1 protein had significant heterogeneity (I²=82.2%, P = .000; I²=92%, P = .000) in OS and DFS, respectively, and further analysis demonstrated that ethnicity, sample size, and histopathological origin were considered to be the main factors affecting their heterogeneity. In addition, high Pim-1 was associated with lymph node metastasis (OR 1.40 [95% CI 1.02-1.92], P = .04), distant metastasis (OR 2.69 [95%CI 1.67-4.35], P < .0001), and clinical stage III-IV (OR .7 [95% CI .50-.96, P = .03). Sensitivity analysis suggested that the pooled results of each effect-size were stable and reliable, and there was no significant publication bias (P = .138) in all included articles.

Conclusion

High Pim-1 can not only predict poor OS and DFS of cancer, but also help to infer the malignant clinical characteristics of tumor metastasis. Pim-1 may be a potential and promising biomarker for early diagnosis, prognostic analysis and targeted therapy of tumors.

Ventilagolin Suppresses Migration, Invasion and Epithelial-Mesenchymal Transition of Hepatocellular Carcinoma Cells by Downregulating Pim-1

Objective

Inhibition of tumor metastasis is a useful strategy to improve the efficacy of cancer therapy. Ventilagolin, a natural 1, 4-naphthoquinone derivative extracted from Ventilago leiocarpa Benth, has shown promising antitumor effects in previous studies. However, the effects and underlying mechanisms of Ventilagolin against migration, invasion and epithelial-mesenchymal transition (EMT) of hepatocellular carcinoma (HCC) remain unclear. The present study has examined these effects and determined whether the proto-oncogene Pim-1 is involved.

Methods

The effects of Ventilagolin on migration, invasion, Pim-1 and EMT-related proteins (eg, E-cadherin, N-cadherin, Vimentin) expression were assessed by scratch wound healing, Transwell, qRT-PCR and Western blot assays, respectively. Pim-1 stably overexpressed HepG2 and SMMC-7721 cells were generated to explore whether Ventilagolin inhibited migration, invasion and EMT of HCC cells via regulating Pim-1. Subcutaneous xenograft tumor model in nude mice was established. Histopathological changes of tumor tissues were examined by H&E staining and expressions of Pim-1 and EMT-related proteins were detected by immunohistochemistry.

Results

Ventilagolin significantly (P < 0.01) reduced the expression of Pim-1 levels in HepG2 and SMMC-7721 cells. Compared with the control group, the migration and invasion abilities of Pim-1-overexpressing HepG2 and SMMC-7721 cells were significantly (P < 0.05, P < 0.01) enhanced, the expression of E-cadherin was decreased (P < 0.01), and the levels of N-cadherin and Vimentin were upregulated (P < 0.05, P < 0.01). Ventilagolin treatment effectively reversed these effects of Pim-1 overexpression. In vivo experiments showed that Ventilagolin could effectively suppress HCC tumor growth, downregulate Pim-1, N-cadherin and Vimentin expression, and upregulate E-cadherin expression.

Conclusion

Ventilagolin suppresses HCC cell proliferation, migration and invasion and reverses EMT process by downregulating Pim-1, suggesting Ventilagolin is a potential therapeutic agent for treatment of HCC.

The dicyano compound induces autophagic or apoptotic cell death via Twist/c-Myc axis depending on metastatic characteristics of breast cancer cells

BACKGROUND

Breast cancer (BC) is a heterogeneous disease with various subtypes, therefore, the illumination of distinctive mechanisms between subtypes for the development of novel treatment strategies is important. Here, we revealed the antiproliferative effects of our customized dicyano compound (DC) on BC cells.

METHODS AND RESULTS

We determined the antiproliferative effect of the DC on non-metastatic MCF-7 and metastatic MDA-MB-231 cell lines by MTT. We evaluated protein levels of LC3BI-II and p62 to detect effects of the DC on autophagy. Furthermore, we examined whether the DC induce apoptosis in MCF-7 and MDA-MB-231 cells by performing TUNEL and western blotting. We showed that the DC induces autophagic cell death in MDA-MB-231 while it leads to apoptosis in MCF-7, demonstrating that DC can induce different cell death mechanisms in BC cells according to what they represent subtypes. To understand the reason of different cell response to the DC, we evaluated the expressions of several regulator proteins involved in survival, cell arrest and proliferation. All findings revealed that c-Myc expression is directly correlated with autophagy induction in BC cells and it could be a marker for the selection of cell death mechanism against anti-cancer drugs. Interestingly, we showed that the overexpression of Twist, responsible for metastatic features of BC cells, imitates the effects of autophagy on c-Myc expression in MCF-7 cells, indicating that it is implicated in both the regulation of c-Myc as a upstream factor and subsequently the selection of cell death mechanisms.

CONCLUSION

Taken together, we suggest that Twist/c-Myc axis may have a role in different response to the DC-induced cell death pathways in BC subtypes with different invasive characteristics.

Dihydroartemisinin inhibits IL-6-induced epithelial-mesenchymal transition in laryngeal squamous cell carcinoma via the miR-130b-3p/STAT3/β-catenin signaling pathway

Objective

To explore whether dihydroartemisinin (DHA) can block interleukin (IL)-6-induced epithelial–mesenchymal transition (EMT) in laryngeal squamous cell carcinoma (LSCC).

Methods

The expression of SLUG, signal transducer and activator of transcription 3 (STAT3), and microRNA (miR)-130b-3p was measured. In addition, a dual-luciferase reporter assay was performed to examine the interaction of miR-130b-3p with STAT3.

Results

We found that IL-6 can promote EMT and invasion in LSCC cells, whereas DHA can inhibit these two processes. However, DHA alone does not influence EMT and cancer invasion. Furthermore, DHA upregulated miR-130b-3p, which can downregulate STAT3 and β-catenin protein expression and decrease the activity of the IL-6/STAT3 signaling pathway. Moreover, we found that miR-130b-3p can target STAT3 directly.

Conclusions

DHA can block IL-6-triggered EMT and invasion in LSCC, and during these processes, DHA increases miR-130b-3p expression to decrease the activation of the IL-6/STAT3 and β-catenin signaling pathways. These findings may provide new insights into strategies for suppressing and even preventing LSCC metastasis.

Decreased IL-6 and NK Cells in Early-Stage Lung Adenocarcinoma Presenting as Ground-Glass Opacity

Background

Lung ground-glass opacities (GGOs) are an early manifestation of lung adenocarcinoma. It is of great value to study the changes in the immune microenvironment of GGO to elucidate the occurrence and evolution of early lung adenocarcinoma. Although the changes of IL-6 and NK cells in lung adenocarcinoma have caught global attention, we have little appreciation for how IL-6 and NK cells in the lung GGO affect the progression of early lung adenocarcinoma.

Methods

We analyzed the RNA sequencing data of surgical specimens from 21 patients with GGO-featured primary lung adenocarcinoma and verified the changes in the expression of IL-6 and other important immune molecules in the TCGA and GEO databases. Next, we used flow cytometry to detect the protein expression levels of important Th1/Th2 cytokines in GGO and normal lung tissues and the changes in the composition ratio of tumor infiltrating lymphocytes (TILs). Then, we analyzed the effect of IL-6 on NK cells through organoid culture and immunofluorescence. Finally, we explored the changes of related molecules and pathway might be involved.

Results

IL-6 may play an important role in the tumor microenvironment of early lung adenocarcinoma. Further research confirmed that the decrease of IL-6 in GGO tissue is consistent with the changes in NK cells, and there seems to be a correlation between these two phenomena.

Conclusion

The IL-6 expression status and NK cell levels of early lung adenocarcinoma as GGO are significantly reduced, and the stimulation of IL-6 can up-regulate or activate NK cells in GGO, providing new insights into the diagnosis and pathogenesis of early lung cancer.

Mesenchymal stem cell conditioned medium attenuates oxidative stress injury in hepatocytes partly by regulating the miR-486-5p/PIM1 axis and the TGF-β/Smad pathway

This study investigated the role of microRNA (miRNA) miR-486-5p in oxidative stress injury in hepatocytes under the treatment of mesenchymal stem cell conditioned medium (MSC-CM). The oxidative stress injury in hepatocytes (L02) was induced by H₂O₂. Human umbilical cord blood MSC-CM (UCB-MSC-CM) was prepared. The effects of UCB-MSC-CM on the proliferation, apoptosis, and inflammatory response in L02 cells were detected by Cell Counting Kit-8 (CCK-8) assay, flow cytometry analysis, and enzyme-linked immunosorbent assay (ELISA). Subsequently, the target of miR-486-5p was predicted using bioinformatics analysis, and the possible signaling pathway addressed by miR-486-5p was explored using western blot. We found that miR-486-5p expression was elevated following oxidative stress injury and was reduced after UCB-MSC-CM treatment. UCB-MSC-CM protected L02 cells against H₂O₂-induced injury by downregulation of miR-486-5p. Proviral integration site for Moloney murine leukemia virus 1 (PIM1) was verified to be targeted by miR-486-5p. UCB-MSC-CM upregulated the expression of PIM1 reduced by H₂O₂ in L02 cells. Additionally, silencing PIM1 attenuated the protective effects of miR-486-5p downregulation against oxidative stress injury. We further demonstrated that UCB-MSC-CM inhibited the TGF-β/Smad signaling in H₂O_2-treated L02 cells by the miR-486-5p/PIM1 axis. Overall, UCB-MSC-CM attenuates oxidative stress injury in hepatocytes by downregulating miR-486-5p and upregulating PIM1, which may be related to the inhibition of TGF-β/Smad pathway.

STAT3 pathway as a molecular target for resveratrol in breast cancer treatment

Signal transducer and activator of transcription 3 (STAT3) induces breast cancer malignancy. Recent clinical and preclinical studies have demonstrated an association between overexpressed and activated STAT3 and breast cancer progression, proliferation, metastasis, and chemoresistance. Resveratrol (RES), a naturally occurring phytoalexin, has demonstrated anti-cancer activity in several disease models. Furthermore, RES has also been shown to regulate the STAT3 signaling cascade via its anti-oxidant and anti-inflammatory effects. In the present review, we describe the STAT3 cascade signaling pathway and address the therapeutic targeting of STAT3 by RES as a tool to mitigate breast cancer.

The Role of the IL-6 Cytokine Family in Epithelial-Mesenchymal Plasticity in Cancer Progression

Epithelial–mesenchymal plasticity (EMP) plays critical roles during embryonic development, wound repair, fibrosis, inflammation and cancer. During cancer progression, EMP results in heterogeneous and dynamic populations of cells with mixed epithelial and mesenchymal characteristics, which are required for local invasion and metastatic dissemination. Cancer development is associated with an inflammatory microenvironment characterized by the accumulation of multiple immune cells and pro-inflammatory mediators, such as cytokines and chemokines. Cytokines from the interleukin 6 (IL-6) family play fundamental roles in mediating tumour-promoting inflammation within the tumour microenvironment, and have been associated with chronic inflammation, autoimmunity, infectious diseases and cancer, where some members often act as diagnostic or prognostic biomarkers. All IL-6 family members signal through the Janus kinase (JAK)–signal transducer and activator of transcription (STAT) pathway and are able to activate a wide array of signalling pathways and transcription factors. In general, IL-6 cytokines activate EMP processes, fostering the acquisition of mesenchymal features in cancer cells. However, this effect may be highly context dependent. This review will summarise all the relevant literature related to all members of the IL-6 family and EMP, although it is mainly focused on IL-6 and oncostatin M (OSM), the family members that have been more extensively studied.

Direct phosphorylation and stabilization of HIF-1α by PIM1 kinase drives angiogenesis in solid tumors

Angiogenesis is essential for the sustained growth of solid tumors. Hypoxia-inducible factor 1 (HIF-1) is a master regulator of angiogenesis and constitutive activation of HIF-1 is frequently observed in human cancers. Therefore, understanding the mechanisms governing the activation of HIF-1 is critical for successful therapeutic targeting of tumor angiogenesis. Herein, we establish a new regulatory mechanism responsible for the constitutive activation of HIF-1α in cancer, irrespective of oxygen tension. PIM1 kinase directly phosphorylates HIF-1α at threonine 455, a previously uncharacterized site within its oxygen-dependent degradation domain. This phosphorylation event disrupts the ability of prolyl hydroxylases to bind and hydroxylate HIF-1α, interrupting its canonical degradation pathway and promoting constitutive transcription of HIF-1 target genes. Moreover, phosphorylation of the analogous site in HIF-2α (S435) stabilizes the protein through the same mechanism, indicating post-translational modification within the oxygen-dependent degradation domain as a mechanism of regulating the HIF-α subunits. In vitro and in vivo models demonstrate that expression of PIM1 is sufficient to stabilize HIF-1α and HIF-2α in normoxia and stimulate angiogenesis in a HIF-1-dependent manner. CRISPR mutants of HIF-1α (Thr455D) promoted increased tumor growth, proliferation, and angiogenesis. Moreover, HIF-1α-T455D xenograft tumors were refractory to the anti-angiogenic and cytotoxic effects of PIM inhibitors. These data identify a new signaling axis responsible for hypoxia-independent activation of HIF-1 and expand our understanding of the tumorigenic role of PIM1 in solid tumors.

Exploring the endogenous potential of Hemidesmus indicus against breast cancer using in silico studies and quantification of 2-hydroxy-4-methoxy benzaldehyde through RP-HPLC

Being a woman and getting older are the main risk factors for breast cancer. While admitting the increasing prevalence of breast cancer among females globally, there is an increasing urge for widening the range of chemical compounds that can act as potential inhibitors for certain cancer target receptors. Current investigation involves virtually screening of 19 protein receptors having major role in signal transduction pathway of breast cancer development against 47 compounds present in Hemidesmus indicus. Virtual screening and supplementary analysis were performed using freely available softwares, tools and online servers. To obtain meaningful results, a comparative scenario was created by screening FDA-approved drugs/drug analogues against the same 19 receptors by keeping all the parameters same as to that of ligands. Two ligands namely Taraxasteryl acetate and Rutin were found to be the best ligands with high binding affinity towards six protein receptors establishing strong receptor ligand interactions. Furthermore, the major volatile compound, a high demand flavouring agent and an isomer of vanillin, namely 2-hydroxy-4-methoxy benzaldehyde (MBALD) specifically found in the roots of Hemidesmus, was quantified by RP-HPLC using a reverse phase C-18 column. The methanolic extract of fresh roots was found to contain 0.221 mg of MBALD/gram of tissue. From the current investigation, it could be surmised that Hemidesmus indicus had demonstrated its potential in both pharmaceuticals and the food industry.

Assessment of differentially methylated loci in individuals with end-stage kidney disease attributed to diabetic kidney disease: an exploratory study

BACKGROUND

A subset of individuals with type 1 diabetes mellitus (T1DM) are predisposed to developing diabetic kidney disease (DKD), the most common cause globally of end-stage kidney disease (ESKD). Emerging evidence suggests epigenetic changes in DNA methylation may have a causal role in both T1DM and DKD. The aim of this exploratory investigation was to assess differences in blood-derived DNA methylation patterns between individuals with T1DM-ESKD and individuals with long-duration T1DM but no evidence of kidney disease upon repeated testing to identify potential blood-based biomarkers. Blood-derived DNA from individuals (107 cases, 253 controls and 14 experimental controls) were bisulphite treated before DNA methylation patterns from both groups were generated and analysed using Illumina's Infinium MethylationEPIC BeadChip arrays (n = 862,927 sites). Differentially methylated CpG sites (dmCpGs) were identified (false discovery rate adjusted p ≤ × 10-8 and fold change ± 2) by comparing methylation levels between ESKD cases and T1DM controls at single site resolution. Gene annotation and functionality was investigated to enrich and rank methylated regions associated with ESKD in T1DM.

RESULTS

Top-ranked genes within which several dmCpGs were located and supported by functional data with methylation look-ups in other cohorts include: AFF3, ARID5B, CUX1, ELMO1, FKBP5, HDAC4, ITGAL, LY9, PIM1, RUNX3, SEPTIN9 and UPF3A. Top-ranked enrichment pathways included pathways in cancer, TGF-β signalling and Th17 cell differentiation.

CONCLUSIONS

Epigenetic alterations provide a dynamic link between an individual's genetic background and their environmental exposures. This robust evaluation of DNA methylation in carefully phenotyped individuals has identified biomarkers associated with ESKD, revealing several genes and implicated key pathways associated with ESKD in individuals with T1DM.

Co-Targeting PIM Kinase and PI3K/mTOR in NSCLC

Simple Summary

PIM kinases interact with major oncogenic players, including the PI3K/Akt pathway, and provide an escape mechanism leading to drug resistance. This study examined PIM kinase expression in NSCLC and the potential of PIM1 as a prognostic marker. The effect on cell signaling of novel preclinical PI3K/mTOR/PIM kinase inhibitor IBL-301 was compared to PI3K/mTOR inhibition in vitro and ex vivo. PI3K-mTOR inhibitor sensitive (H1975P) and resistant (H1975GR) cells were compared for altered IL6/STAT3 pathway expression and sensitivity to IBL-301. All three PIM kinases are expressed in NSCLC and PIM1 is a marker of poor prognosis. IBL-301 inhibited c-Myc, the PI3K-Akt and JAK/STAT pathways in vitro and in NSCLC tumor tissue explants. IBL-301 also inhibited secreted pro-inflammatory cytokine MCP-1. PIM kinases were activated in H1975GR cells which were more sensitive to IBL-301 than H1975P cells. A miRNA signature of PI3K-mTOR resistance was validated. Co-targeting PIM kinase and PI3K-mTOR warrants further clinical investigation.

Abstract

PIM kinases are constitutively active proto-oncogenic serine/threonine kinases that play a role in cell cycle progression, metabolism, inflammation and drug resistance. PIM kinases interact with and stabilize p53, c-Myc and parallel signaling pathway PI3K/Akt. This study evaluated PIM kinase expression in NSCLC and in response to PI3K/mTOR inhibition. It investigated a novel preclinical PI3K/mTOR/PIM inhibitor (IBL-301) in vitro and in patient-derived NSCLC tumor tissues. Western blot analysis confirmed PIM1, PIM2 and PIM3 are expressed in NSCLC cell lines and PIM1 is a marker of poor prognosis in patients with NSCLC. IBL-301 decreased PIM1, c-Myc, pBAD and p4EBP1 (Thr37/46) and peIF4B (S406) protein levels in-vitro and MAP kinase, PI3K-Akt and JAK/STAT pathways in tumor tissue explants. IBL-301 significantly decreased secreted pro-inflammatory cytokine MCP-1. Altered mRNA expression, including activated PIM kinase and c-Myc, was identified in Apitolisib resistant cells (H1975GR) by an IL-6/STAT3 pathway array and validated by Western blot. H1975GR cells were more sensitive to IBL-301 than parent cells. A miRNA array identified a dysregulated miRNA signature of PI3K/mTOR drug resistance consisting of regulators of PIM kinase and c-Myc (miR17-5p, miR19b-3p, miR20a-5p, miR15b-5p, miR203a, miR-206). Our data provides a rationale for co-targeting PIM kinase and PI3K-mTOR to improve therapeutic response in NSCLC.

Structure-Based Virtual Screening and De Novo Design of PIM1 Inhibitors with Anticancer Activity from Natural Products

BACKGROUND

the proviral insertion site of Moloney murine leukemia (PIM) 1 kinase has served as a therapeutic target for various human cancers due to the enhancement of cell proliferation and the inhibition of apoptosis.

METHODS

to identify effective PIM1 kinase inhibitors, structure-based virtual screening of natural products of plant origin and de novo design were carried out using the protein-ligand binding free energy function improved by introducing an adequate dehydration energy term.

RESULTS

as a consequence of subsequent enzyme inhibition assays, four classes of PIM1 kinase inhibitors were discovered, with the biochemical potency ranging from low-micromolar to sub-micromolar levels. The results of extensive docking simulations showed that the inhibitory activity stemmed from the formation of multiple hydrogen bonds in combination with hydrophobic interactions in the ATP-binding site. Optimization of the biochemical potency by chemical modifications of the 2-benzylidenebenzofuran-3(2H)-one scaffold led to the discovery of several nanomolar inhibitors with antiproliferative activities against human breast cancer cell lines.

CONCLUSIONS

these new PIM1 kinase inhibitors are anticipated to serve as a new starting point for the development of anticancer medicine.

IL-6 in inflammation, autoimmunity and cancer

IL-6 is involved both in immune responses and in inflammation, hematopoiesis, bone metabolism and embryonic development. IL-6 plays roles in chronic inflammation (closely related to chronic inflammatory diseases, autoimmune diseases and cancer) and even in the cytokine storm of corona virus disease 2019 (COVID-19). Acute inflammation during the immune response and wound healing is a well-controlled response, whereas chronic inflammation and the cytokine storm are uncontrolled inflammatory responses. Non-immune and immune cells, cytokines such as IL-1β, IL-6 and tumor necrosis factor alpha (TNFα) and transcription factors nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) play central roles in inflammation. Synergistic interactions between NF-κB and STAT3 induce the hyper-activation of NF-κB followed by the production of various inflammatory cytokines. Because IL-6 is an NF-κB target, simultaneous activation of NF-κB and STAT3 in non-immune cells triggers a positive feedback loop of NF-κB activation by the IL-6-STAT3 axis. This positive feedback loop is called the IL-6 amplifier (IL-6 Amp) and is a key player in the local initiation model, which states that local initiators, such as senescence, obesity, stressors, infection, injury and smoking, trigger diseases by promoting interactions between non-immune cells and immune cells. This model counters dogma that holds that autoimmunity and oncogenesis are triggered by the breakdown of tissue-specific immune tolerance and oncogenic mutations, respectively. The IL-6 Amp is activated by a variety of local initiators, demonstrating that the IL-6-STAT3 axis is a critical target for treating diseases.

Targeting PIM1-Mediated Metabolism in Myeloid Suppressor Cells to Treat Cancer

There is a strong correlation between myeloid-derived suppressor cells (MDSC) and resistance to immune checkpoint blockade (ICB), but the detailed mechanisms underlying this correlation are largely unknown. Using single-cell RNA sequencing analysis in a bilateral tumor model, we found that immunosuppressive myeloid cells with characteristics of fatty acid oxidative metabolism dominate the immune-cell landscape in ICB-resistant subjects. In addition, we uncovered a previously underappreciated role of a serine/threonine kinase, PIM1, in regulating lipid oxidative metabolism via PPARγ-mediated activities. Enforced PPARγ expression sufficiently rescued metabolic and functional defects of Pim1 ^-/- MDSCs. Consistent with this, pharmacologic inhibition of PIM kinase by AZD1208 treatment significantly disrupted the myeloid cell-mediated immunosuppressive microenvironment and unleashed CD8⁺ T-cell-mediated antitumor immunity, which enhanced PD-L1 blockade in preclinical cancer models. PIM kinase inhibition also sensitized nonresponders to PD-L1 blockade by selectively targeting suppressive myeloid cells. Overall, we have identified PIM1 as a metabolic modulator in MDSCs that is associated with ICB resistance and can be therapeutically targeted to overcome ICB resistance.

Gene expression in circulating tumor cells reveals a dynamic role of EMT and PD-L1 during osimertinib treatment in NSCLC patients

Liquid biopsy is a tool to unveil resistance mechanisms in NSCLC. We studied changes in gene expression in CTC-enriched fractions of EGFR-mutant NSCLC patients under osimertinib. Peripheral blood from 30 NSCLC patients before, after 1 cycle of osimertinib and at progression of disease (PD) was analyzed by size-based CTC enrichment combined with RT-qPCR for gene expression of epithelial (CK-8, CK-18, CK-19), mesenchymal/EMT (VIM, TWIST-1, AXL), stem cell (ALDH-1) markers, PD-L1 and PIM-1. CTCs were also analyzed by triple immunofluorescence for 45 identical blood samples. Epithelial and stem cell profile (p = 0.043) and mesenchymal/EMT and stem cell profile (p = 0.014) at PD were correlated. There was a strong positive correlation of VIM expression with PIM-1 expression at baseline and increased PD-L1 expression levels at PD. AXL overexpression varied among patients and high levels of PIM-1 transcripts were detected. PD-L1 expression was significantly increased at PD compared to baseline (p = 0.016). The high prevalence of VIM positive CTCs suggest a dynamic role of EMT during osimertinib treatment, while increased expression of PD-L1 at PD suggests a theoretical background for immunotherapy in EGFR-mutant NSCLC patients that develop resistance to osimertinib. This observation merits to be further evaluated in a prospective immunotherapy trial.

Targeting PIM Kinases to Overcome Therapeutic Resistance in Cancer

Cancer progression and the onset of therapeutic resistance are often the results of uncontrolled activation of survival kinases. The proviral integration for the Moloney murine leukemia virus (PIM) kinases are oncogenic serine/threonine kinases that regulate tumorigenesis by phosphorylating a wide range of substrates that control cellular metabolism, proliferation, and survival. Because of their broad impact on cellular processes that facilitate progression and metastasis in many cancer types, it has become clear that the activation of PIM kinases is a significant driver of resistance to various types of anticancer therapies. As a result, efforts to target PIM kinases for anticancer therapy have intensified in recent years. Clinical and preclinical studies indicate that pharmacologic inhibition of PIM has the potential to significantly improve the efficacy of standard and targeted therapies. This review focuses on the signaling pathways through which PIM kinases promote cancer progression and resistance to therapy, as well as highlights biological contexts and promising strategies to exploit PIM as a therapeutic target in cancer.

Inflammation driven tumor-like signaling in prostatic epithelial cells by sexually transmitted Trichomonas vaginalis

OBJECTIVES

To identify the sequence of inflammation-driven signaling cascades and other molecular events that might cause tumor-like transformation of prostatic cells.

METHODS

Cytokine array analysis, Reactome and STRING analysis, immunoblotting, and immunocytochemistry were used to investigate the molecular mechanisms governing inflammation-driven adverse changes in human prostatic cells caused by the sexually transmitted infection, Trichomonas vaginalis, resulting in prostatitis, benign prostatic hyperplasia and prostate cancer.

RESULTS

Array analysis showed upregulation of 23 cytokines within 24 h of infection of human prostatic epithelial RWPE-1 cells with the parasite, in vitro. Reactome and STRING analysis of array data identified interleukin-6, interleukin-8, nuclear factor kappa B, signal transducer and activator of transcription 3 and cyclooxygenase 2 as chief instigators of prostatic anomaly, which were found to be significantly upregulated by immunofluorescence and western blotting analyses. STRING further connected these instigators with macrophage migration inhibitory factor, PIM-1 and prostate-specific antigen; which was confirmed by their marked stimulation in infected prostatic cells by immunoblotting and immunocytochemistry. Upregulated proliferation markers, such as Ki67, proliferating cell nuclear antigen and B-cell lymphoma 2, suggested tumor-like signaling in infected RWPE-1 cells, which was further supported by downregulation of E-cadherin, upregulation of vimentin and activation of focal adhesion kinase. Prostate tumor DU145 cells were more sensitive to parasite invasion, and showed rapid upregulation with nuclear translocation of sensitive parameters, such as nuclear factor kappa B, signal transducer and activator of transcription 3, and macrophage migration inhibitory factor. The migration of DU145 cells augmented when incubated in spent media from parasite-infected RWPE-1 cells.

CONCLUSION

The initiation of inflammation driven tumor-like cell signaling in parasite-infected human prostatic epithelial cells is apparent, with the prostate tumor (DU145) cells being more sensitive to T. vaginalis than normal (RWPE-1) prostatic cells.

The pleiotropic role of transcription factor STAT3 in oncogenesis and its targeting through natural products for cancer prevention and therapy

Signal transducer and activator of transcription 3 (STAT3) is one of the crucial transcription factors, responsible for regulating cellular proliferation, cellular differentiation, migration, programmed cell death, inflammatory response, angiogenesis, and immune activation. In this review, we have discussed the classical regulation of STAT3 via diverse growth factors, cytokines, G-protein-coupled receptors, as well as toll-like receptors. We have also highlighted the potential role of noncoding RNAs in regulating STAT3 signaling. However, the deregulation of STAT3 signaling has been found to be associated with the initiation and progression of both solid and hematological malignancies. Additionally, hyperactivation of STAT3 signaling can maintain the cancer stem cell phenotype by modulating the tumor microenvironment, cellular metabolism, and immune responses to favor drug resistance and metastasis. Finally, we have also discussed several plausible ways to target oncogenic STAT3 signaling using various small molecules derived from natural products.

MYC as a Multifaceted Regulator of Tumor Microenvironment Leading to Metastasis

The Myc family of oncogenes is deregulated in many types of cancer, and their over-expression is often correlated with poor prognosis. The Myc family members are transcription factors that can coordinate the expression of thousands of genes. Among them, c-Myc (MYC) is the gene most strongly associated with cancer, and it is the focus of this review. It regulates the expression of genes involved in cell proliferation, growth, differentiation, self-renewal, survival, metabolism, protein synthesis, and apoptosis. More recently, novel studies have shown that MYC plays a role not only in tumor initiation and growth but also has a broader spectrum of functions in tumor progression. MYC contributes to angiogenesis, immune evasion, invasion, and migration, which all lead to distant metastasis. Moreover, MYC is able to promote tumor growth and aggressiveness by recruiting stromal and tumor-infiltrating cells. In this review, we will dissect all of these novel functions and their involvement in the crosstalk between tumor and host, which have demonstrated that MYC is undoubtedly the master regulator of the tumor microenvironment. In sum, a better understanding of MYC’s role in the tumor microenvironment and metastasis development is crucial in proposing novel and effective cancer treatment strategies.

Inhibition of PIM1 kinase attenuates bleomycin-induced pulmonary fibrosis in mice by modulating the ZEB1/E-cadherin pathway in alveolar epithelial cells

PIM1 is serine/threonine protein kinase that is involved in numerous biological processes. Pulmonary fibrosis (PF) is a chronic pathological result of the dysfunctional repair of lung injury without effective therapeutic treatments. In the current study, we investigated whether PIM1 inhibition would improve bleomycin (BLM)-induced pulmonary fibrosis. In a BLM-induced pulmonary fibrosis model, PIM1 was persistently upregulated in fibrotic lung tissues. Furthermore, PIM1 inhibition by the PIM1-specific inhibitor SMI-4a showed protective effects against BLM-induced mortality. Furthermore, SMI-4a suppressed hydroxyproline deposition and reversed epithelial-mesenchymal transition (EMT) formation, which was characterized by E-cadherin and α-SMA expression in vivo. More importantly, the ZEB1/E-cadherin pathway was found to be closely associated with BLM-induced pulmonary fibrosis. After the in vitro treatment of A549 cells, PIM1 regulated E-cadherin expression by dependently modulating the activity of the transcription factor ZEB1. These findings were verified in vivo after SMI-4a administration. Finally, an shPIM1-expressing adeno-associated virus was delivered via intratracheal injection to induce a long-term PIM1 deficiency in the alveolar epithelium. AAV-mediated PIM1 knockdown in the lung tissues alleviated BLM-induced pulmonary fibrosis, as indicated by collagen accumulation reduction, pulmonary histopathological mitigation and EMT reversion. These findings enhance our understanding of the roles of PIM1 in BLM-induced pulmonary fibrosis and suggest PIM1 inhibition as a potential therapeutic strategy in chronic pulmonary injuries.

Chromatin modified protein 4C (CHMP4C) facilitates the malignant development of cervical cancer cells

Despite improvements in prevention and treatment, cervical cancer (CC) still poses a serious threat to women’s health. CHMP4C (chromatin modified protein 4C) is a subunit of the endosomal sorting complex required for transport, which is expressed in both nucleus and cytoplasm. Here, we examined the effect of CHMP4C on the biological behavior of CC cells and the underlying mechanisms. We report that CHMP4C expression is higher in CC tissues, and high CHMP4C expression is associated with lower survival. Up‐regulation of CHMP4C in C‐33A cells accelerates cell proliferation, migration and invasion, whereas down‐regulation of CHMP4C in Ca Ski cells had the opposite effect. Moreover, overexpression of CHMP4C induced activation of the epithelial–mesenchymal transition pathway, whereas depletion of CHMP4C inhibited activation. Our results suggest that CHMP4C contributes to the viability and motility of CC cells by modulating epithelial–mesenchymal transition and may facilitate the identification of novel biomarkers for CC therapy.

Senescence-Associated Pro-inflammatory Cytokines and Tumor Cell Plasticity

The well-recognized cell phenotypic heterogeneity in tumors is a great challenge for cancer treatment. Dynamic interconversion and movement within a spectrum of different cell phenotypes (cellular plasticity) with the acquisition of specific cell functions is a fascinating biological puzzle, that represent an additional difficulty for cancer treatment and novel therapies development. The understanding of the molecular mechanisms responsible for moving or stabilizing tumor cells within this spectrum of variable states constitutes a valuable tool to overcome these challenges. In particular, cell transitions between epithelial and mesenchymal phenotypes (EMT-MET) and de-and trans-differentiation processes are relevant, since it has been shown that they confer invasiveness, drug resistance, and metastatic ability, due to the simultaneous acquisition of stem-like cell properties. Multiple drivers participate in these cell conversions events. In particular, cellular senescence and senescence-associated soluble factors have been shown to unveil stem-like cell properties and cell plasticity. By modulating gradually the composition of their secretome and the time of exposure, senescent cells may have differential effect not only on tumor cells but also on surrounding cells. Intriguingly, tumor cells that scape from senescence acquire stem-like cell properties and aggressiveness. The reinforcement of senescence and inflammation by soluble factors and the participation of immune cells may provide a dynamic milieu having varied effects on cell transitions, reprogramming, plasticity, stemness and therefore heterogeneity. This will confer different epithelial/mesenchymal traits (hybrid phenotype) and stem-like cell properties, combinations of which, in a particular cell context, could be responsible for different cellular functions during cancer progression (survival, migration, invasion, colonization or proliferation). Additionally, cooperative behavior between cell subpopulations with different phenotypes/stemness functions could also modulate their cellular plasticity. Here, we will discuss the role of senescence and senescence-associated pro-inflammatory cytokines on the induction of cellular plasticity, their effect role in establishing particular states within this spectrum of cell phenotypes and how this is accompanied by stem-like cell properties that, as the epithelial transitions, may also have a continuum of characteristics providing tumor cells with functional adaptability specifically useful in the different stages of carcinogenesis.

[Expression and role of Pim1 in cultured cortical neurons with oxygen-glucose deprivation/reoxygen injury]

OBJECTIVE

To study the expression and effect of Pim1 in primary cortical neurons after hypoxic-ischemic injury.

METHODS

Cortical neurons were isolated from 1-day-old C57BL/6 mice and cultured in neurobasal medium. On the 8th day of neuron culture, cells were subjected to oxygen-glucose deprivation/reoxygen (OGD/R) treatment to mimic in vivo hypoxic injury of neurons. Briefly, medium were changed to DMEM medium, and cells were cultured in 1% O₂ for 3 hours and then changed back to normal medium and conditions. Cells were collected at 0 hour, 6 hours, 12 hours and 24 hours after OGD/R. Primary neurons were transfected with Pim1 overexpression plasmid or mock plasmid, and then were exposed to normal conditions or OGD/R treatment. They were named as Pim1 group, control group, OGD/R group and OGD/R+Pim1 group respectively. Real-time PCR was used to detect Pim1 mRNA expression. Western blot was used to detect the protein expression of Pim1 and apoptotic related protein cleaved caspase 3 (CC3). TUNEL staining was used to detect cell apoptosis.

RESULTS

Real-time PCR and Western blot results showed that Pim1 mRNA and protein were significantly decreased in neurons after OGD/R. They began to decrease at 0 hour after OGD/R, reached to the lowest at 12 hours after OGD/R, and remained at a lower level at 24 hours after OGD/R (P<0.01). Overexpression of Pim1 significantly upregulated the protein level of Pim1. Under OGD/R conditions, the CC3 expression and the apoptosis rate in cells of the Pim1 group were significantly lower than in un-transfected cells (P<0.01).

CONCLUSIONS

Hypoxic-ischemic injury may decrease Pim1 expression in neurons. Overexpressed Pim1 may inhibit apoptosis induced by OGD/R.

Bit1 Silencing Enhances the Proliferation, Migration, and Invasion of Glioma Cells Through Activation of the IL-6/STAT3 Pathway

Background

Several studies have indicated that the anoikis effector Bcl-2 inhibitor of transcription 1 (Bit1) can promote or inhibit tumor progression depending on the nature of the malignancy. However, its regulatory effects on gliomas are unknown.

Methods

This study aimed at assessing Bit1 expression in glioma tissues and cells, its subsequent effects on glioma cell apoptosis, proliferation, invasion, and migration, and the underlying molecular mechanisms.

Results

The findings showed that lower Bit1 expressions in glioma tissues as well as a negative correlation between Bit1 expression and glioma grade. Additional findings also revealed that Bit1 silencing significantly inhibited anoikis and enhanced glioma cell proliferation, invasion, and migration. Further analysis showed that the decrease in Bit1 expressions led to malignancy proliferation and anoikis resistance through activation of the IL-6/STAT3 signaling pathway.

Conclusion

Our data suggested that Bit1 may play an anti-oncogenic role in glioma cells and that a decrease in its expressions might induce glioma cell proliferation, migration, and invasion through the IL-6/STAT3 signaling pathway.

PIM1 inhibitor synergizes the anti-tumor effect of osimertinib via STAT3 dephosphorylation in EGFR-mutant non-small cell lung cancer

Background

An increasing amount of evidence has demonstrated that combined or multiple targeted therapies could bring about more durable clinical outcomes, and it is known that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) resistance is related to bypass activation. This study aims to explore a specific solution for third-generation EGFR-TKI resistance caused by bypass activation, and to examine the antitumor effects of the combination of a novel inhibitor CX-6258 HCl with osimertinib, along with its underlining mechanisms.

Methods

A bioinformatics analysis was performed to detect the relations between the provirus integration site for Moloney murine leukemia virus 1 (PIM1) expression and prognosis of lung cancer. The EGFR-mutated lung cancer cell lines were treated with the combination of CX-6258 HCl and osimertinib to analyze cell proliferation using the Cell Counting Kit-8, colony formation, and in vivo experiments. Cell migration was analyzed using wound healing and Transwell assays. The apoptosis level was detected using Annexin V-propidium iodide flow cytometry. The expression levels of EGFR and STAT3 were determined using Western blot analysis.

Results

High expression level of PIM1 was related to the poor prognosis of non-small cell lung cancer (NSCLC). The combined administration of osimertinib and CX-6258 HCl significantly inhibited cell proliferation and migration and effectively induced apoptosis in lung cancer cells. It was more efficient in suppressing EGFR activation and phosphorylation of STAT3 compared with osimertinib treatment alone. Furthermore, it showed a durable efficacy in a xenograft model.

Conclusions

This study showed that PIM1 is a poor prognostic factor for NSCLC. CX-6258 HCl is a potential molecular inhibitor to sensitize the antitumor effects of osimertinib through the inhibiting of the phosphorylation of STAT3 in NSCLC.

Role of STAT3 signaling pathway in breast cancer

Breast cancer has grown to be the second leading cause of cancer-related deaths in women. Only a few treatment options are available for breast cancer due to the widespread occurrence of chemoresistance, which emphasizes the need to discover and develop new methods to treat this disease. Signal transducer and activator of transcription 3 (STAT3) is an early tumor diagnostic marker and is known to promote breast cancer malignancy. Recent clinical and preclinical data indicate the involvement of overexpressed and constitutively activated STAT3 in the progression, proliferation, metastasis and chemoresistance of breast cancer. Moreover, new pathways comprised of upstream regulators and downstream targets of STAT3 have been discovered. In addition, small molecule inhibitors targeting STAT3 activation have been found to be efficient for therapeutic treatment of breast cancer. This systematic review discusses the advances in the discovery of the STAT3 pathways and drugs targeting STAT3 in breast cancer. Video abstract.

Overview of the STAT-3 signaling pathway in cancer and the development of specific inhibitors

Signal transducer and activator of transcription (STAT) proteins represent novel therapeutic targets for the treatment of cancer. In particular, STAT-3 serves critical roles in several cellular processes, including the cell cycle, cell proliferation, cellular apoptosis and tumorigenesis. Persistent activation of STAT-3 has been reported in a variety of cancer types, and a poor prognosis of cancer may be associated with the phosphorylation level of STAT-3. Furthermore, elevated STAT-3 activity has been demonstrated in a variety of mammalian cancers, both in vitro and in vivo. This indicates that STAT-3 serves an important role in the progression of numerous cancer types. A significant obstacle in developing STAT-3 inhibitors is the demonstration of the antitumor efficacy in in vivo systems and the lack of animal models for human tumors. Therefore, it is crucial to determine whether available STAT-3 inhibitors are suitable for clinical trials. Moreover, further preclinical studies are necessary to focus on the impact of STAT-3 inhibitors on tumor cells. When considering STAT-3 hyper-activation in human cancer, selective targeting to these proteins holds promise for significant advancement in cancer treatment. In the present study, advances in our knowledge of the structure of STAT-3 protein and its regulatory mechanisms are summarized. Moreover, the STAT-3 signaling pathway and its critical role in malignancy are discussed, in addition to the development of STAT-3 inhibitors in various cancer types.

Role of JAK/STAT3 Signaling in the Regulation of Metastasis, the Transition of Cancer Stem Cells, and Chemoresistance of Cancer by Epithelial-Mesenchymal Transition

The JAK/STAT3 signaling pathway plays an essential role in various types of cancers. Activation of this pathway leads to increased tumorigenic and metastatic ability, the transition of cancer stem cells (CSCs), and chemoresistance in cancer via enhancing the epithelial–mesenchymal transition (EMT). EMT acts as a critical regulator in the progression of cancer and is involved in regulating invasion, spread, and survival. Furthermore, accumulating evidence indicates the failure of conventional therapies due to the acquisition of CSC properties. In this review, we summarize the effects of JAK/STAT3 activation on EMT and the generation of CSCs. Moreover, we discuss cutting-edge data on the link between EMT and CSCs in the tumor microenvironment that involves a previously unknown function of miRNAs, and also discuss new regulators of the JAK/STAT3 signaling pathway.

Targeted Inhibition of miR-221/222 Promotes Cell Sensitivity to Cisplatin in Triple-Negative Breast Cancer MDA-MB-231 Cells

Cisplatin has been widely used in the treatment of a various types of cancers including triple-negative breast cancer (TNBC) by damaging DNA and inducing apoptosis. However, its anti-cancer effects are often limited due to chemo-resistance, which is one of the main reasons causing cancer relapse and metastasis. To overcome resistance, cisplatin is often used in combination with other drugs or molecules. Our study found that the targeted inhibition of miR-221/222 in MDA-MB-231 cells promoted cisplatin-induced cell apoptosis, and increased the cell sensitivity to cisplatin in vitro. Much higher expression levels of miR-221/222 were detected in the cisplatin-resistant MDA-MB-231 cells and in cisplatin-resistant breast cancer patients. The combination chemotherapy of cisplatin with anti-miR-221/222 showed much higher efficiency in suppressing tumor growth in the mice transplanted with MDA-MB-231 cells. In addition, anti-miR-221 and anti-miR-222 showed synergetic effects on improving sensitivity to cisplatin in MDA-MB-231 cells. Suppression of SOCS1-STAT3-Bcl-2 pathway and activation of p53-Pten signaling both contribute to anti-miR-221/222-induced sensitivity to cisplatin in MDA-MB-231 cells. These findings suggest the potential of a novel approach for the combination chemotherapy of cisplatin with small non-coding RNA in treatment of human TNBC.