Advances in Immunomodulation and Immune Engineering Approaches to Improve Healing of Extremity Wounds

Delayed healing of traumatic wounds often stems from a dysregulated immune response initiated or exacerbated by existing comorbidities, multiple tissue injury or wound contamination. Over decades, approaches towards alleviating wound inflammation have been centered on interventions capable of a collective dampening of various inflammatory factors and/or cells. However, a progressive understanding of immune physiology has rendered deeper knowledge on the dynamic interplay of secreted factors and effector cells following an acute injury. There is a wide body of literature, both in vitro and in vivo, abstracted on the immunomodulatory approaches to control inflammation. Recently, targeted modulation of the immune response via biotechnological approaches and biomaterials has gained attention as a means to restore the pro-healing phenotype and promote tissue regeneration. In order to fully realize the potential of these approaches in traumatic wounds, a critical and nuanced understanding of the relationships between immune dysregulation and healing outcomes is needed. This review provides an insight on paradigm shift towards interventional approaches to control exacerbated immune response following a traumatic injury from an agonistic to a targeted path. We address such a need by (1) providing a targeted discussion of the wound healing processes to assist in the identification of novel therapeutic targets and (2) highlighting emerging technologies and interventions that utilize an immunoengineering-based approach. In addition, we have underscored the importance of immune engineering as an emerging tool to provide precision medicine as an option to modulate acute immune response following a traumatic injury. Finally, an overview is provided on how an intervention can follow through a successful clinical application and regulatory pathway following laboratory and animal model evaluation.

The chromosome 21 kinase DYRK1A: emerging roles in cancer biology and potential as a therapeutic target

Dual-specificity tyrosine phosphorylation-regulated kinase 1 A (DYRK1A) is a serine/threonine kinase that belongs to the DYRK family of proteins, a subgroup of the evolutionarily conserved CMGC protein kinase superfamily. Due to its localization on chromosome 21, the biological significance of DYRK1A was initially characterized in the pathogenesis of Down syndrome (DS) and related neurodegenerative diseases. However, increasing evidence has demonstrated a prominent role in cancer through its ability to regulate biologic processes including cell cycle progression, DNA damage repair, transcription, ubiquitination, tyrosine kinase activity, and cancer stem cell maintenance. DYRK1A has been identified as both an oncogene and tumor suppressor in different models, underscoring the importance of cellular context in its function. Here, we review mechanistic contributions of DYRK1A to cancer biology and its role as a potential therapeutic target.

DDX17-regulated alternative splicing that produced an oncogenic isoform of PXN-AS1 to promote HCC metastasis

BACKGROUND AND AIMS

The mechanism underlying HCC metastasis remains unclear, many oncogenes are known to regulate this process. However, the role of alternative splicing (AS) in pro-metastatic HCC is poorly understood.

APPROACH AND RESULTS

By performing RNA sequencing on nine pairs of primary HCC tissues with extrahepatic metastasis (EHMH) and nine pairs of metastasis-free HCC (MFH) tissues, we depicted the AS landscape in HCC and found a higher frequency of AS events in EHMH compared with MFH. Moreover, 28 differentially expressed splicing regulators were identified in EHMH compared with MFH. Among these, DEAD-box RNA helicase 17 (DDX17) was significantly up-regulated in EHMH and was strongly associated with patient outcome. Functional studies indicated that DDX17 knockout inhibited the degradation of the extracellular matrix, and diminished the invasive ability of HCC cells. A significant reduction in lung metastasis induced by DDX17 deficiency was also demonstrated in a diethylnitrosamine-induced DDX17^HKO mouse model. Mechanistically, high DDX17 induced intron 3 retention of PXN-AS1 and produced a transcript (termed PXN-AS1-IR3). The transcript PXN-AS1-IR3 acted as an important promoter of HCC metastasis by inducing MYC transcription activation via recruiting the complex of testis expressed 10 and p300 to the MYC enhancer region, which led to transcriptional activation of several metastasis-associated downstream genes. Finally, the PXN-AS1-IR3 level was significantly higher in serum and HCC tissues with extrahepatic metastasis.

CONCLUSIONS

DDX17 and PXN-AS1-IR3 act as important metastatic promoters by modulating MYC signaling, suggesting that DDX17 and PXN-AS1-IR3 may be potential prognostic markers for metastatic HCC.

Extracellular Vesicles in Transplantation

Extracellular vesicles (EVs) have been extensively studied in the last two decades. It is now well documented that they can actively participate in the activation or regulation of immune system functions through different mechanisms, the most studied of which include protein–protein interactions and miRNA transfers. The functional diversity of EV-secreting cells makes EVs potential targets for immunotherapies through immune cell-derived EV functions. They are also a potential source of biomarkers of graft rejection through donor cells or graft environment-derived EV content modification. This review focuses on preclinical studies that describe the role of EVs from different cell types in immune suppression and graft tolerance and on the search for biomarkers of rejection.

Extracellular vesicles delivering nuclear factor I/C for hard tissue engineering: Treatment of apical periodontitis and dentin regeneration

Apical periodontitis (AP) causes arrest of tooth root development, which is associated with impaired odontoblastic differentiation of stem cells from apical papilla (SCAPs), but the underlying mechanism remains unclear. Here, we investigated roles of extracellular vesicle (EV) in AP and odontoblastic differentiation of SCAPs, moreover, a novel nuclear factor I/C (NFIC)-encapsulated EV was developed to promote dentin regeneration. We detected a higher expression of EV marker CD63 in inflamed apical papilla, and found that EVs from LPS-stimulated dental pulp cells suppressed odontoblastic differentiation of SCAPs through downregulating NFIC. Furthermore, we successfully constructed the NFIC-encapsulated EV by overexpressing NFIC in HEK293FT cells, which could upregulate cellular NFIC level in SCAPs, promoting the proliferation and migration of SCAPs, as well as dentinogenesis both in vitro and in vivo. Collectively, based on pathological roles of EV in AP, our study provides a novel strategy for dentin regeneration by exploiting EV to deliver NFIC.

Isolation of Extracellular Vesicles From Microalgae: A Renewable and Scalable Bioprocess

Extracellular vesicles (EVs) play a crucial role as potent signal transducers among cells, with the potential to operate cross-species and cross-kingdom communication. Nanoalgosomes are a subtype of EVs recently identified and isolated from microalgae. Microalgae represent a natural bioresource with the capacity to produce several secondary metabolites with a broad range of biological activities and commercial applications. The present study highlights the upstream and downstream processes required for the scalable production of nanoalgosomes from cultures of the marine microalgae Tetraselmis chuii. Different technical parameters, protocols, and conditions were assessed to improve EVs isolation by tangential flow filtration (TFF), aiming to enhance sample purity and yield. The optimization of the overall bioprocess was enhanced by quality control checks operated through robust biophysical and biochemical characterizations. Further, we showed the possibility of recycling by TFF microalgae cells post-EVs isolation for multiple EV production cycles. The present results highlight the potential of nanoalgosome production as a scalable, cost-effective bioprocess suitable for diverse scientific and industrial exploitations.

The RNA helicases DDX5 and DDX17 facilitate neural differentiation of human pluripotent stem cells NTERA2

AIMS

Understanding human neurogenesis is critical toward regenerative medicine for neurodegeneration. However, little is known how neural differentiation is regulated by DEAD box-containing RNA helicases, which comprise a diverse class of RNA remodeling enzymes.

MATERIALS AND METHODS

ChIP-seq was utilized to identify binding sites of DDX5 and DDX17 in both human pluripotent stem cell (hPSC) line NTERA2 and their retinoic acid-induced neural derivatives. RNA-seq was used to elucidate genes differentially expressed upon depletion of DDX5 and DDX17. Neurosphere assay, flow cytometry, and immunofluorescence staining were performed to test the effect of depletion of the two RNA helicases in neural differentiation.

KEY FINDINGS

We show here that expression of DDX5 and DDX17 is abundant throughout neural differentiation of NTERA2, and is mostly localized within the nucleus. The two RNA helicases occupy chromatin genome-wide at regions associated with neurogenesis-related genes in both hPSCs and their neural derivatives. Further, both DDX5 and DDX17 are mutually required for controlling transcriptional expression of these genes, but are not important for maintenance of stem cell state of hPSCs. In contrast, they facilitate early neural differentiation of hPSCs, generation of neurospheres from the stem cells, and transcriptional expression of key neurogenic transcription factors such as SOX1 and PAX6 during neural differentiation. Importantly, DDX5 and DDX17 are critical for differentiation of hPSCs toward NESTIN- and TUBB3-positive cells, which represent neural progenitors and mature neurons, respectively.

SIGNIFICANCE

Collectively, our findings suggest the role of DDX5 and DDX17 in transcriptional regulation of genes involved in neurogenesis, and hence in neural differentiation of hPSCs.

A novel FBW7/NFAT1 axis regulates cancer immunity in sunitinib-resistant renal cancer by inducing PD-L1 expression

Background

Tyrosine kinase inhibitors (TKIs) alone and in combination with immune checkpoint inhibitors (ICIs) have been shown to be beneficial for the survival of metastatic renal cell carcinoma (mRCC) patients, but resistance to targeted therapy and ICIs is common in the clinic. Understanding the underlying mechanism is critical for further prolonging the survival of renal cancer patients. Nuclear factor of activated T cell 1 (NFAT1) is expressed in immune and nonimmune cells, and the dysregulation of NFAT1 contributes to the progression of various type of malignant tumors. However, the specific role of NFAT1 in RCC is elusive. As a regulator of the immune response, we would like to systemically study the role of NFAT1 in RCC.

Methods

TCGA-KIRC dataset analysis, Western blot analysis and RT-qPCR analysis was used to determine the clinic-pathological characteristic of NFAT1 in RCC. CCK-8 assays, colony formation assays and xenograft assays were performed to examine the biological role of NFAT1 in renal cancer cells. RNA-seq analysis was used to examine the pathways changed after NFAT1 silencing. ChIP-qPCR, coimmunoprecipitation analysis, Western blot analysis and RT-qPCR analysis were applied to explore the mechanism by NAFT1 was regulated in the renal cancer cells.

Results

In our study, we found that NFAT1 was abnormally overexpressed in RCC and that NFAT1 overexpression was associated with an unfavorable prognosis. Then, we showed that NFAT1 enhanced tumor growth and regulated the immune response by increasing PD-L1 expression in RCC. In addition, we demonstrated that NFAT1 was stabilized in sunitinib-resistant RCC via hyperactivation of the PI3K/AKT/GSK-3β signaling pathway. Furthermore, our study indicated that downregulation of the expression of FBW7, which promotes NFAT1 degradation, was induced by FOXA1 and SETD2 in sunitinib-resistant RCC. Finally, FBW7 was found to contribute to modulating the immune response in RCC.

Conclusions

Our data reveal a novel role for the FBW7/NFAT1 axis in the RCC response to TKIs and ICIs. NFAT1 and its associated signaling pathway might be therapeutic targets for RCC treatment, especially when combined with ICIs and/or TKIs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02253-0.

Targeted Delivery of Exosomes Armed with Anti-Cancer Therapeutics

Among extracellular vesicles, exosomes have gained great attention for their role as therapeutic vehicles for delivering various active pharmaceutical ingredients (APIs). Exosomes “armed” with anti-cancer therapeutics possess great potential for an efficient intracellular delivery of anti-cancer APIs and enhanced targetability to tumor cells. Various technologies are being developed to efficiently incorporate anti-cancer APIs such as genetic materials (miRNA, siRNA, mRNA), chemotherapeutics, and proteins into exosomes and to induce targeted delivery to tumor burden by exosomal surface modification. Exosomes can incorporate the desired therapeutic molecules via direct exogenous methods (e.g., electroporation and sonication) or indirect methods by modifying cells to produce “armed” exosomes. The targeted delivery of “armed” exosomes to tumor burden could be accomplished either by “passive” targeting using the natural tropism of exosomes or by “active” targeting via the surface engineering of exosomal membranes. Although anti-cancer exosome therapeutics demonstrated promising results in preclinical studies, success in clinical trials requires thorough validation in terms of chemistry, manufacturing, and control techniques. While exosomes possess multiple advantages over synthetic nanoparticles, challenges remain in increasing the loading efficiency of anti-cancer agents into exosomes, as well as establishing quantitative and qualitative analytical methods for monitoring the delivery of in vivo administered exosomes and exosome-incorporated anti-cancer agents to the tumor parenchyma.

Association between nuclear factor of activated T cells C2 polymorphisms and treatment response in rheumatoid arthritis patients receiving tumor necrosis factor-alpha inhibitors

OBJECTIVES

Nuclear factor of activated T cells C2 (NFATC2) is known as a member of the transcription family and enhances tumor necrosis factor-alpha (TNF-α) synthesis in human T cells at the gene transcription level. Although NFATC2 has a potential role in rheumatoid arthritis (RA) progression and treatment, no study has investigated the association between NFATC2 gene polymorphisms and response status in RA patients receiving TNF-α inhibitors. This study aimed to examine the effects of polymorphisms in NFATC2, a TNF-α transcription factor, on response to TNF-α inhibitors.

METHODS

This prospective observational study was performed in two centers. Seven single nucleotide polymorphisms (SNPs) were investigated. Good responders were defined as patients with disease activity score (DAS)28 ≤3.2 after 6 months of treatment. Logistic regression analyses were used to investigate the association between genetic polymorphisms and response to the treatment. To test the model's goodness of fit, a Hosmer-Lemeshow test was performed.

RESULTS

This study included 98 patients, among whom 46 showed favorable responses to the treatment. Patients with hypertension revealed an approximately three-fold lower response to TNF-α inhibitors compared to those without hypertension (23.5 vs. 76.5%; P = 0.049). After adjusting for covariates, C allele carriers of NFATC2 rs3787186 exhibited approximately three-fold lower rates of treatment response compared to those with TT genotype (P = 0.037). The Hosmer-Lemeshow test showed that the fitness of the multivariable analysis model was satisfactory (χ2 = 9.745; 8 degrees of freedom; P = 0.283).

CONCLUSION

This study suggested an association between the C allele of rs3787186 and treatment response in RA patients receiving TNF-α inhibitors.

Regulation of TNF-Induced Osteoclast Differentiation

Increased osteoclast (OC) differentiation and activity is the critical event that results in bone loss and joint destruction in common pathological bone conditions, such as osteoporosis and rheumatoid arthritis (RA). RANKL and its decoy receptor, osteoprotegerin (OPG), control OC differentiation and activity. However, there is a specific concern of a rebound effect of denosumab discontinuation in treating osteoporosis. TNFα can induce OC differentiation that is independent of the RANKL/RANK system. In this review, we discuss the factors that negatively and positively regulate TNFα induction of OC formation, and the mechanisms involved to inform the design of new anti-resorptive agents for the treatment of bone conditions with enhanced OC formation. Similar to, and being independent of, RANKL, TNFα recruits TNF receptor-associated factors (TRAFs) to sequentially activate transcriptional factors NF-κB p50 and p52, followed by c-Fos, and then NFATc1 to induce OC differentiation. However, induction of OC formation by TNFα alone is very limited, since it also induces many inhibitory proteins, such as TRAF3, p100, IRF8, and RBP-j. TNFα induction of OC differentiation is, however, versatile, and Interleukin-1 or TGFβ1 can enhance TNFα-induced OC formation through a mechanism which is independent of RANKL, TRAF6, and/or NF-κB. However, TNFα polarized macrophages also produce anabolic factors, including insulin such as 6 peptide and Jagged1, to slow down bone loss in the pathological conditions. Thus, the development of novel approaches targeting TNFα signaling should focus on its downstream molecules that do not affect its anabolic effect.

[Therapeutic applications of extracellular vesicles]

Extracellular vesicles, secreted spontaneously or in response to stress by all cell types, are proposed as alternative biotherapies to cellular therapies and to synthetic nanomedicines. Their logistical advantages (storage, stability, availability, tolerance), their ability to cross biological barriers, to deliver their contents (proteins, lipids and nucleic acids) in order to modify their target cells, as well as their immunomodulatory and regenerative activities, are of growing interest for a very wide spectrum of diseases. Here we review the challenges to bring these biotherapies to the clinic and discuss some promising applications in cancer and regenerative medicine.

A targetable LIFR-NF-κB-LCN2 axis controls liver tumorigenesis and vulnerability to ferroptosis

The growing knowledge of ferroptosis has suggested the role and therapeutic potential of ferroptosis in cancer, but has not been translated into effective therapy. Liver cancer, primarily hepatocellular carcinoma (HCC), is highly lethal with limited treatment options. LIFR is frequently downregulated in HCC. Here, by studying hepatocyte-specific and inducible Lifr-knockout mice, we show that loss of Lifr promotes liver tumorigenesis and confers resistance to drug-induced ferroptosis. Mechanistically, loss of LIFR activates NF-κB signaling through SHP1, leading to upregulation of the iron-sequestering cytokine LCN2, which depletes iron and renders insensitivity to ferroptosis inducers. Notably, an LCN2-neutralizing antibody enhances the ferroptosis-inducing and anticancer effects of sorafenib on HCC patient-derived xenograft tumors with low LIFR expression and high LCN2 expression. Thus, anti-LCN2 therapy is a promising way to improve liver cancer treatment by targeting ferroptosis.

Anti-Cancer Role and Therapeutic Potential of Extracellular Vesicles

Cell-cell communication is an important mechanism in biological processes. Extracellular vesicles (EVs), also referred to as exosomes, microvesicles, and prostasomes, are microvesicles secreted by a variety of cells. EVs are nanometer-scale vesicles composed of a lipid bilayer and contain biological functional molecules, such as microRNAs (miRNAs), mRNAs, and proteins. In this review, "EVs" is used as a comprehensive term for vesicles that are secreted from cells. EV research has been developing over the last four decades. Many studies have suggested that EVs play a crucial role in cell-cell communication. Importantly, EVs contribute to cancer malignancy mechanisms such as carcinogenesis, proliferation, angiogenesis, metastasis, and escape from the immune system. EVs derived from cancer cells and their microenvironments are diverse, change in nature depending on the condition. As EVs are thought to be secreted into body fluids, they have the potential to serve as diagnostic markers for liquid biopsy. In addition, cells can encapsulate functional molecules in EVs. Hence, the characteristics of EVs make them suitable for use in drug delivery systems and novel cancer treatments. In this review, the potential of EVs as anti-cancer therapeutics is discussed.

Deep Proteomic Analysis on Biobanked Paraffine-Archived Melanoma with Prognostic/Predictive Biomarker Read-Out

The discovery of novel protein biomarkers in melanoma is crucial. Our introduction of formalin-fixed paraffin-embedded (FFPE) tumor protocol provides new opportunities to understand the progression of melanoma and open the possibility to screen thousands of FFPE samples deposited in tumor biobanks and available at hospital pathology departments. In our retrospective biobank pilot study, 90 FFPE samples from 77 patients were processed. Protein quantitation was performed by high-resolution mass spectrometry and validated by histopathologic analysis. The global protein expression formed six sample clusters. Proteins such as TRAF6 and ARMC10 were upregulated in clusters with enrichment for shorter survival, and proteins such as AIFI1 were upregulated in clusters with enrichment for longer survival. The cohort's heterogeneity was addressed by comparing primary and metastasis samples, as well comparing clinical stages. Within immunotherapy and targeted therapy subgroups, the upregulation of the VEGFA-VEGFR2 pathway, RNA splicing, increased activity of immune cells, extracellular matrix, and metabolic pathways were positively associated with patient outcome. To summarize, we were able to (i) link global protein expression profiles to survival, and they proved to be an independent prognostic indicator, as well as (ii) identify proteins that are potential predictors of a patient's response to immunotherapy and targeted therapy, suggesting new opportunities for precision medicine developments.

Expanding the Spectrum of EWSR1-NFATC2-rearranged Benign Tumors: A Common Genomic Abnormality in Vascular Malformation/Hemangioma and Simple Bone Cyst

A simple bone cyst (SBC) is a cystic bone lesion predominantly affecting young males. The cyst is lined by a fibrous membrane and filled with serosanguinous fluid. EWSR1/FUS-NFATC2 rearrangements were recently identified in SBC. We here report exactly the same rearrangement in 3 lesions diagnosed as vascular malformations of 2 elderly patients. In total, through Archer FusionPlex, fluorescence in situ hybridization and/or reverse transcriptase-polymerase chain reaction the EWSR1-NFATC2 rearrangement was identified in 6 of 9 SBC, 3 of 12 benign vascular tumors, and none of 5 aneurysmal bone cyst lacking USP6 fusion. Using fluorescence in situ hybridization, it was apparent that amplification of the fusion, as seen in EWSR1-NFATC2 round cell sarcomas, was absent, and that in the vascular tumors the fusion was present both in the lining cells as well as in the surrounding spindle cells. Of note, not all of the spaces in the vascular malformations were lined by endothelial cells. Aggrecan was positive in all cases but was not specific. NKX2-2 and NKX3-1 staining were negative in all cases. Thus, even though the overlap between the 2 entities is limited to the presence of few thick-walled cysts lacking endothelial lining in the benign vascular malformations, the spectrum of benign tumors containing NFATC2 fusions should be expanded and contains not only SBC in the young, but also vascular malformation/hemangioma in elderly patients.

Tonicity-responsive enhancer-binding protein promotes diabetic neuroinflammation and cognitive impairment via upregulation of lipocalin-2

Background

Diabetic individuals have increased circulating inflammatory mediators which are implicated as underlying causes of neuroinflammation and memory deficits. Tonicity-responsive enhancer-binding protein (TonEBP) promotes diabetic neuroinflammation. However, the precise role of TonEBP in the diabetic brain is not fully understood.

Methods

We employed a high-fat diet (HFD)-only fed mice or HFD/streptozotocin (STZ)-treated mice in our diabetic mouse models. Circulating TonEBP and lipocalin-2 (LCN2) levels were measured in type 2 diabetic subjects. TonEBP haploinsufficient mice were used to investigate the role of TonEBP in HFD/STZ-induced diabetic mice. In addition, RAW 264.7 macrophages were given a lipopolysaccharide (LPS)/high glucose (HG) treatment. Using a siRNA, we examined the effects of TonEBP knockdown on RAW264 cell’ medium/HG-treated mouse hippocampal HT22 cells.

Results

Circulating TonEBP and LCN2 levels were higher in experimental diabetic mice or type 2 diabetic patients with cognitive impairment. TonEBP haploinsufficiency ameliorated the diabetic phenotypes including adipose tissue macrophage infiltrations, neuroinflammation, blood–brain barrier leakage, and memory deficits. Systemic and hippocampal LCN2 proteins were reduced in diabetic mice by TonEBP haploinsufficiency. TonEBP (+ / −) mice had a reduction of hippocampal heme oxygenase-1 (HO-1) expression compared to diabetic wild-type mice. In particular, we found that TonEBP bound to the LCN2 promoter in the diabetic hippocampus, and this binding was abolished by TonEBP haploinsufficiency. Furthermore, TonEBP knockdown attenuated LCN2 expression in lipopolysaccharide/high glucose-treated mouse hippocampal HT22 cells.

Conclusions

These findings indicate that TonEBP may promote neuroinflammation and cognitive impairment via upregulation of LCN2 in diabetic mice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02331-8.

NFATc1 promotes epithelial-mesenchymal transition and facilitates colorectal cancer metastasis by targeting SNAI1

Metastatic recurrence remains a major cause of colorectal cancer (CRC) mortality. In this study, we investigated the mechanistic role of nuclear factor of activated T cells 1 (NFATc1) in CRC metastasis. First, we explored the potential role of NFATc1 in CRC using bioinformatics and hypothesized that NFATc1 might play different roles at different stages of CRC development. Then, we examined the relative expression of NFATc1 in 25 CRC tissues and adjacent normal tissues, and further analyzed the correlation between NFATc1 expression levels and clinical stages in 120 CRC patients. The role of NFATc1 in CRC metastasis and the molecular mechanisms were investigated in both in vitro and in vivo models. Our results showed that the expression of NFATc1 was increased in metastatic CRC tissues and positively associated with clinical stages (stage I vs. stage II, III or IV) of CRC. Overexpression of NFATc1 promoted CRC cell migration, invasion, and epithelial-mesenchymal transition (EMT). Moreover, SNAI1 was verified as the direct transcriptional target of NFATc1 and interacted with SLUG to promote EMT. Remarkably, our lung and liver metastasis mouse model demonstrated that NFATc1 overexpression accelerated CRC metastasis, and treatment with FK506, a calcineurin-NFAT pathway inhibitor, could suppress CRC metastasis in vivo. Taken together, our findings suggest that NFATc1 could transcriptionally activate SNAI1, which in turn interacts with SLUG to mediate EMT to promote CRC metastasis. Thus, making NFATc1 a promising therapeutic target in the treatment of metastatic CRC.

Actin Beta-Like 2 as a New Mediator of Proliferation and Migration in Epithelial Ovarian Cancer

The impact of Actin beta-like 2 (ACTBL2), a novel described actin isoform, on epithelial ovarian cancer (EOC) biology has not been investigated so far. In this study, we analyzed the prognostic and functional significance of ACTBL2 and its regulatory element Nuclear factor of activated T-cells 5 (NFAT5). The expression of ACTBL2 and NFAT5 was examined in tissue microarrays of 156 ovarian cancer patients by immunohistochemistry. Aiming to assess the molecular impact of ACTBL2 on cellular characteristics, functional assays were executed in vitro upon siRNA knockdown of ACTBL2 and NFAT5. ACTBL2 expression was identified as an independent negative prognostic factor for overall survival of EOC patients. EOC cell lines showed a significantly increased mRNA and protein level of ACTBL2 compared to the benign control. In vitro analyses upon siRNA knockdown of ACTBL2 displayed a significantly reduced cellular viability, proliferation and migration. siRNA knockdown of NFAT5 proved a significant molecular interplay by inducing a downregulation of ACTBL2 with a thus resulting concordant alteration in cellular functions, predominantly reflected in a decreased migratory potential of EOC cells. Our results provide significant evidence on the negative prognostic impact of ACTBL2 in EOC, suggesting its crucial importance in ovarian carcinogenesis by modulating cellular motility and proliferation.

Tumor-Derived Exosomal Protein Tyrosine Phosphatase Receptor Type O Polarizes Macrophage to Suppress Breast Tumor Cell Invasion and Migration

Tumor-derived exosomes, containing multiple nucleic acids and proteins, have been implicated to participate in the interaction between tumor cells and microenvironment. However, the functional involvement of phosphatases in tumor-derived exosomes is not fully understood. We and others previously demonstrated that protein tyrosine phosphatase receptor type O (PTPRO) acts as a tumor suppressor in multiple cancer types. In addition, its role in tumor immune microenvironment remains elusive. Bioinformatical analyses revealed that PTPRO was closely associated with immune infiltration, and positively correlated to M1-like macrophages, but negatively correlated to M2-like macrophages in breast cancer tissues. Co-cultured with PTPRO-overexpressing breast cancer cells increased the proportion of M1-like tumor-associated macrophages (TAMs) while decreased that of M2-like TAMs. Further, we observed that tumor-derived exosomal PTPRO induced M1-like macrophage polarization, and regulated the corresponding functional phenotypes. Moreover, tumor cell-derived exosomal PTPRO inhibited breast cancer cell invasion and migration, and inactivated STAT signaling in macrophages. Our data suggested that exosomal PTPRO inhibited breast cancer invasion and migration by modulating macrophage polarization. Anti-tumoral effect of exosomal PTPRO was mediated by inactivating STAT family in macrophages. These findings highlight a novel mechanism of tumor invasion regulated by tumor-derived exosomal tyrosine phosphatase, which is of translational potential for the therapeutic strategy against breast cancer.

DYRK1A activates NFATC1 to increase glioblastoma migration

Glioblastoma (GBM) is the most aggressive glioma, and is prone to develop resistance to chemotherapy and radiotherapy; hence, patients with glioblastoma have a high recurrence rate and a low 1-year survival rate. In addition, the pathogenesis of glioblastoma is complex and largely unknown, and the available treatments are limited. Here, we uncovered a fundamental role of DYRK1A in regulating NFATC1 in GBMs. We found that DYRK1A was highly expressed in glioma and glioblastoma cells, and its expression was positively correlated with that of NFATC1. Moreover, inhibition of DYRK1A promoted NFATC1 degradation in GBM cells and sharply reduced the transactivation of NFATC1, not only by decreasing the expression of NFATC1-targeted genes, but also by reducing the luciferase activity, and vice versa. However, DYRK1A had the opposite effect on NFATC2. Most importantly, our data suggest that DYRK1A inhibition reduces glioblastoma migration. Polypeptides derived from the DYRK1A-targeted motif of NFATC1, by competitively blocking DYRK1A kinase activity on NFATC1, clearly destabilized NFATC1 protein and impaired glioblastoma migration. We propose that the recovery of NFATC1 stability is a key oncogenic event in a large proportion of gliomas, and pharmacological inhibition of DYRK1A by polypeptides could represent a promising therapeutic intervention for GBM.

Calcineurin-nuclear factor for activated T cells (NFAT) signaling in pathophysiology of wound healing

Wound healing occurred with serial coordinated processes via coagulation-fibrinolysis, inflammation following to immune-activation, angiogenesis, granulation, and the final re-epithelization. Since the dermis forms critical physical and biological barriers, the repair system should be rapidly and accurately functioned to keep homeostasis in our body. The wound healing is impaired or dysregulated via an inappropriate microenvironment, which is easy to lead to several diseases, including fibrosis in multiple organs and psoriasis. Such a disease led to the dysregulation of several types of cells: immune cells, fibroblasts, mural cells, and endothelial cells. Moreover, recent progress in medical studies uncovers the significant concept. The calcium signaling, typically the following calcineurin-NFAT signaling, essentially regulates not only immune cell activations, but also various healing steps via coagulation, inflammation, and angiogenesis. In this review, we summarize the role of the NFAT activation pathway in wound healing and discuss its overall impact on future therapeutic ways.

CD40 Cross-Linking Induces Migration of Renal Tumor Cell through Nuclear Factor of Activated T Cells (NFAT) Activation

CD40 crosslinking plays an important role in regulating cell migration, adhesion and proliferation in renal cell carcinoma (RCC). CD40/CD40L interaction on RCC cells activates different intracellular pathways but the molecular mechanisms leading to cell scattering are not yet clearly defined. Aim of our study was to investigate the main intracellular pathways activated by CD40 ligation and their specific involvement in RCC cell migration. CD40 ligation increased the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH (2)-terminal kinase (JNK) and p38 MAPK. Furthermore, CD40 crosslinking activated different transcriptional factors on RCC cell lines: AP-1, NFkB and some members of the Nuclear Factor of Activated T cells (NFAT) family. Interestingly, the specific inhibition of NFAT factors by cyclosporine A, completely blocked RCC cell motility induced by CD40 ligation. In tumor tissue, we observed a higher expression of NFAT factors and in particular an increased activation and nuclear migration of NFATc4 on RCC tumor tissues belonging to patients that developed metastases when compared to those who did not. Moreover, CD40-CD40L interaction induced a cytoskeleton reorganization and increased the expression of integrin β1 on RCC cell lines, and this effect was reversed by cyclosporine A and NFAT inhibition. These data suggest that CD40 ligation induces the activation of different intracellular signaling pathways, in particular the NFATs factors, that could represent a potential therapeutic target in the setting of patients with metastatic RCC.

Role of Nuclear Factor of Activated T Cells (NFAT) Pathway in Regulating Autophagy and Inflammation in Retinal Pigment Epithelial Cells

Nuclear factor of activated T cells (NFAT) family of transcription factors are substrates of calcineurin and play an important role in integrating Ca²⁺ signaling with a variety of cellular functions. Of the five NFAT proteins (NFAT1-5), NFAT1-4 are subject to dephosphorylation and activation by calcineurin, a Ca²⁺-calmodulin-dependent phosphatase. Increased levels of intracellular Ca²⁺ activates calcineurin, which in turn dephosphorylates and promotes nuclear translocation of NFAT. We investigated the functions of NFAT proteins in the retinal pigment epithelial cells (RPE). Our results show that NFAT-mediated luciferase activity was induced upon treatment with the bacterial endotoxin, lipopolysaccharide (LPS) and treatment with the NFAT peptide inhibitor, MAGPHPVIVITGPHEE (VIVIT) decreased LPS-induced NFAT luciferase activity. LPS-induced activation of NFAT-regulated cytokines (IL-6 and IL-8) is inhibited by treatment of cells with VIVIT. We also investigated the effects of NFAT signaling on the autophagy pathway. Our results show that inhibition of NFAT with VIVIT in cells deprived of nutrients resulted in cytosolic retention of transcription Factor EB (TFEB), decreased expression of TFEB-regulated coordinated Lysosomal Expression and Regulation CLEAR network genes and decreased starvation-induced autophagy flux in the RPE cells. In summary, these studies suggest that the NFAT pathway plays an important role in the regulation of autophagy and inflammation in the RPE.

Akt Isoforms: A Family Affair in Breast Cancer

Simple Summary

Breast cancer is the second leading cause of cancer-related death in women in the United States. The Akt signaling pathway is deregulated in approximately 70% of patients with breast cancer. While targeting Akt is an effective therapeutic strategy for the treatment of breast cancer, there are several members in the Akt family that play distinct roles in breast cancer. However, the function of Akt isoforms depends on many factors. This review analyzes current progress on the isoform-specific functions of Akt isoforms in breast cancer.

Abstract

Akt, also known as protein kinase B (PKB), belongs to the AGC family of protein kinases. It acts downstream of the phosphatidylinositol 3-kinase (PI3K) and regulates diverse cellular processes, including cell proliferation, cell survival, metabolism, tumor growth and metastasis. The PI3K/Akt signaling pathway is frequently deregulated in breast cancer and plays an important role in the development and progression of breast cancer. There are three closely related members in the Akt family, namely Akt1(PKBα), Akt2(PKBβ) and Akt3(PKBγ). Although Akt isoforms share similar structures, they exhibit redundant, distinct as well as opposite functions. While the Akt signaling pathway is an important target for cancer therapy, an understanding of the isoform-specific function of Akt is critical to effectively target this pathway. However, our perception regarding how Akt isoforms contribute to the genesis and progression of breast cancer changes as we gain new knowledge. The purpose of this review article is to analyze current literatures on distinct functions of Akt isoforms in breast cancer.

NFAT transcription factors are essential and redundant actors for leukemia initiating potential in T-cell acute lymphoblastic leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy with few available targeted therapies. We previously reported that the phosphatase calcineurin (Cn) is required for LIC (leukemia Initiating Capacity) potential of T-ALL pointing to Cn as an interesting therapeutic target. Calcineurin inhibitors have however unwanted side effect. NFAT transcription factors play crucial roles downstream of calcineurin during thymocyte development, T cell differentiation, activation and anergy. Here we elucidate NFAT functional relevance in T-ALL. Using murine T-ALL models in which Nfat genes can be inactivated either singly or in combination, we show that NFATs are required for T-ALL LIC potential and essential to survival, proliferation and migration of T-ALL cells. We also demonstrate that Nfat genes are functionally redundant in T-ALL and identified a node of genes commonly deregulated upon Cn or NFAT inactivation, which may serve as future candidate targets for T-ALL.

Dominant effect of gap junction communication in wound-induced calcium-wave, NFAT activation and wound closure in keratinocytes

Wounding induces a calcium wave and disrupts the calcium gradient across the epidermis but mechanisms mediating calcium and downstream signalling, and longer-term wound healing responses are incompletely understood. As expected, live-cell confocal imaging of Fluo-4-loaded normal human keratinocytes showed an immediate increase in [Ca²⁺ ]_i at the wound edge that spread as a calcium wave (8.3 µm/s) away from the wound edge with gradually diminishing rate of rise and amplitude. The amplitude and area under the curve of [Ca²⁺ ]_i flux was increased in high (1.2 mM) [Ca²⁺ ]_o media. 18α-glycyrrhetinic acid (18αGA), a gap-junction inhibitor or hexokinase, an ATP scavenger, blocked the wound-induced calcium wave, dependent in part on [Ca²⁺ ]_o . Wounding in a high [Ca²⁺ ]_o increased nuclear factor of activated T-cells (NFAT) but not NFkB activation, assessed by dual-luciferase receptor assays compared to unwounded cells. Treatment with 18αGA or the store-operated channel blocker GSK-7975A inhibited wound-induced NFAT activation, whereas treatment with hexokinase did not. Real-time cell migration analysis, measuring wound closure rates over 24 h, revealed that 18αGA essentially blocked wound closure whereas hexokinase and GSK-7975A showed relatively minimal effects. Together these data indicate that while both gap-junction communication and ATP release from damaged cells are important in regulating the wound-induced calcium wave, long-term transcriptional and functional responses are dominantly regulated by gap-junction communication.

Clinical and Immunologic Predictors of Mycobacterium avium Complex Immune Reconstitution Inflammatory Syndrome in a Contemporary Cohort of Patients With Human Immunodeficiency Virus

BACKGROUND

People with human immunodeficiency virus (HIV) can present with new or worsening symptoms associated with Mycobacterium avium complex (MAC) infection shortly after antiretroviral therapy (ART) initiation as MAC immune reconstitution inflammatory syndrome (MAC-IRIS). In this study, we assessed the utility of several laboratory tests as predictors of MAC-IRIS.

METHODS

People with HIV with clinical and histologic and/or microbiologic evidence of MAC-IRIS were identified and followed up to 96 weeks post-ART initiation within a prospective study of 206 ART-naive patients with CD4 <100 cells/µL.

RESULTS

Fifteen (7.3%) patients presented with MAC-IRIS within a median interval of 26 days after ART initiation. Patients who developed MAC-IRIS had lower body mass index, lower hemoglobin levels, higher alkaline phosphatase (ALP), and increased CD38 frequency and mean fluorescence intensity on CD8+ T cells at the time of ART initiation compared with non-MAC IRIS patients. A decision tree inference model revealed that stratifying patients based on levels of ALP and D-dimer could predict the likelihood of MAC-IRIS. A binary logistic regression demonstrated that higher levels of ALP at baseline were associated with increased risk of MAC-IRIS development.

CONCLUSIONS

High ALP levels and increased CD8+ T-cell activation with low CD4 counts at ART initiation should warrant suspicion for subsequent development of MAC-IRIS.

[6]-Gingerol-Derived Semi-Synthetic Compound SSi6 Inhibits Tumor Growth and Metastatic Dissemination in Triple-Negative Breast Cancer Xenograft Models

Simple Summary

Triple-negative breast cancers (TNBC) represent approximately 15% of all breast cancers and lack the expression of a defined molecular target. This absence makes this subtype of cancer difficult to treat and control. Current chemotherapy drugs cause various side effects and toxicities that can jeopardize the quality of life of patients with TNBC cancer. Therefore, this research focuses on a new semi-synthetic compound derived from [6]-gingerol, where we demonstrate that it does not cause significant toxic effects in vivo and, more importantly, we demonstrate its antitumor and antimetastatic effects using preclinical xenograft models simulating two clinical scenarios of a woman with breast cancer.

Abstract

Breast cancer metastasis is the most common cause of cancer death in women worldwide. Triple-negative breast cancers (TNBC) form a heterogeneous group of tumors that have higher relapse rates and poorer survival compared to other breast cancer subtypes. Thus, this work reports the antitumor and antimetastatic activities of a [6]-gingerol-derived semi-synthetic compound named SSi6 on MDA-MB-231 TNBC cells using xenograft models. SSi6 did not cause toxic effects in vivo as demonstrated by body weight and hematological and histological evaluations. From the orthotopic xenograft model, we demonstrated that SSi6 slows and inhibits the growth of the primary tumor, as well as prevents metastatic spontaneous progression from lymph nodes to the lungs. Moreover, a second xenograft model with resection of the primary tumor showed that SSi6 also blocks the progression of metastases from the lymph nodes to other visceral organs. Taken together, our results demonstrate that SSi6 is a promising compound to be investigated in other preclinical and clinical models to be applied as a complementary therapy for TNBC.

BST2 regulates interferon gamma-dependent decrease in invasion of HTR-8/SVneo cells via STAT1 and AKT signaling pathways and expression of E-cadherin

The mechanism by which interferon-gamma (IFN-γ) downregulates trophoblast invasion needs further investigation. Treatment of HTR-8/SVneo cells with IFN-γ led to a decrease in their invasion concomitant with an increased expression of BST2. Silencing of BST2 by siRNA showed a significant increase in their invasion and spreading after treatment with IFN-γ as well as downregulated expression of E-cadherin. Further, STAT1 silencing inhibited the IFN-γ-dependent increase in the expression of BST2 and E-cadherin. Treatment of HTR-8/SVneo cells with IFN-γ led to the activation of AKT, and its inhibition with PI3K inhibitor abrogated IFN-γ-mediated decrease in invasion/spreading and downregulated BST2 and E-cadherin expression. Collectively, IFN-γ decreases the invasion of HTR-8/SVneo cells by STAT1 and AKT activation via increased expression of BST2 and E-cadherin.

Plastin 3 in health and disease: a matter of balance

For a long time, PLS3 (plastin 3, also known as T-plastin or fimbrin) has been considered a rather inconspicuous protein, involved in F-actin-binding and -bundling. However, in recent years, a plethora of discoveries have turned PLS3 into a highly interesting protein involved in many cellular processes, signaling pathways, and diseases. PLS3 is localized on the X-chromosome, but shows sex-specific, inter-individual and tissue-specific expression variability pointing towards skewed X-inactivation. PLS3 is expressed in all solid tissues but usually not in hematopoietic cells. When escaping X-inactivation, PLS3 triggers a plethora of different types of cancers. Elevated PLS3 levels are considered a prognostic biomarker for cancer and refractory response to therapies. When it is knocked out or mutated in humans and mice, it causes osteoporosis with bone fractures; it is the only protein involved in actin dynamics responsible for osteoporosis. Instead, when PLS3 is upregulated, it acts as a highly protective SMN-independent modifier in spinal muscular atrophy (SMA). Here, it seems to counteract reduced F-actin levels by restoring impaired endocytosis and disturbed calcium homeostasis caused by reduced SMN levels. In contrast, an upregulation of PLS3 on wild-type level might cause osteoarthritis. This emphasizes that the amount of PLS3 in our cells must be precisely balanced; both too much and too little can be detrimental. Actin-dynamics, regulated by PLS3 among others, are crucial in a lot of cellular processes including endocytosis, cell migration, axonal growth, neurotransmission, translation, and others. Also, PLS3 levels influence the infection with different bacteria, mycosis, and other pathogens.

Limited inhibition of multiple nodes in a driver network blocks metastasis

Metastasis suppression by high-dose, multi-drug targeting is unsuccessful due to network heterogeneity and compensatory network activation. Here, we show that targeting driver network signaling capacity by limited inhibition of core pathways is a more effective anti-metastatic strategy. This principle underlies the action of a physiological metastasis suppressor, Raf Kinase Inhibitory Protein (RKIP), that moderately decreases stress-regulated MAP kinase network activity, reducing output to transcription factors such as pro-metastastic BACH1 and motility-related target genes. We developed a low-dose four-drug mimic that blocks metastatic colonization in mouse breast cancer models and increases survival. Experiments and network flow modeling show limited inhibition of multiple pathways is required to overcome variation in MAPK network topology and suppress signaling output across heterogeneous tumor cells. Restricting inhibition of individual kinases dissipates surplus signal, preventing threshold activation of compensatory kinase networks. This low-dose multi-drug approach to decrease signaling capacity of driver networks represents a transformative, clinically relevant strategy for anti-metastatic treatment.

Prognostic value of members of NFAT family for pan-cancer and a prediction model based on NFAT2 in bladder cancer

Bladder cancer (BLCA) is one of the common malignant tumors of the urinary system. The poor prognosis of BLCA patients is due to the lack of early diagnosis and disease recurrence after treatment. Increasing evidence suggests that gene products of the nuclear factor of activated T-cells (NFAT) family are involved in BLCA progression and subsequent interaction(s) with immune surveillance. In this study, we carried out a pan-cancer analysis of the NFAT family and found that NFAT2 is an independent prognostic factor for BLCA. We then screened for differentially expressed genes (DEGs) and further analyzed such candidate gene loci using gene ontology enrichment to curate the KEGG database. We then used Lasso and multivariate Cox regression to identify 4 gene loci (FER1L4, RNF128, EPHB6, and FN1) which were screened together with NFAT2 to construct a prognostic model based on using Kaplan-Meier analysis to predict the overall survival of BLCA patients. Moreover, the accuracy of our proposed model is supported by deposited datasets in the Gene Expression Omnibus (GEO) database. Finally, a nomogram of this prognosis model for BLCA was established which could help to provide better disease management and treatment.

AKT3 is a key regulator of head and neck squamous cell carcinoma

The phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway plays a vital role in cell proliferation, apoptosis, metabolism, and angiogenesis in various human cancers, including head and neck squamous cell carcinoma (HNSCC). In the present study, we aimed to clarify the role of AKT, which is a major downstream effector of the PI3K‐AKT‐mTOR pathway, in HNSCC. We first investigated the mRNA expression of AKT isoforms using RNA‐sequencing data from The Cancer Genome Atlas database. We observed a specific elevation of AKT3 expression in HNSCC tissues when compared with that in normal tissues. Furthermore, AKT3 expression correlated with genes related to the immunosuppressive microenvironment more than the other AKT isoforms and PIK3CA. Accordingly, we focused on AKT3 and performed a knockdown approach using an HNSCC cell line. AKT3 knockdown cells exhibited impaired proliferation, a shift in the cell cycle from G2/M to G1/G0 phase, an increase in apoptotic cells, and downregulation of gene expression related to immunosuppression, as well as the knockdown of its upstream regulator PIK3CA. We also performed immunohistochemistry for both AKT3 and PIK3CA using surgical specimens from 72 patients with HNSCC. AKT3 expression in tumor cells correlated with immune cell infiltration and unfavorable prognosis when compared with PIK3CA. These findings suggested that AKT3 expression is a potential biomarker for predicting the immunoreactivity and prognosis of HNSCC. Furthermore, the isoform‐specific inhibition of AKT3 could be developed as a novel cancer therapy that efficiently suppresses the PI3K‐AKT‐mTOR pathway.

The Transcriptional Co-factor IRF2BP2: A New Player in Tumor Development and Microenvironment

Interferon regulatory factor 2-binding protein 2 (IRF2BP2) encodes a member of the IRF2BP family of transcriptional regulators, which includes IRF2BP1, IRF2BP2, and IRF2BPL (EAP1). IRF2BP2 was initially identified as a transcriptional corepressor that was dependent on Interferon regulatory factor-2 (IRF-2). The IRF2BP2 protein is found in different organisms and has been described as ubiquitously expressed in normal and tumor cells and tissues, indicating a possible role for this transcriptional cofactor in different cell signaling pathways. Recent data suggest the involvement of IRF2BP2 in the regulation of several cellular functions, such as the cell cycle, cell death, angiogenesis, inflammation and immune response, thereby contributing to physiological cell homeostasis. However, an imbalance in IRF2BP2 function may be related to the pathophysiology of cancer. Some studies have shown the association of IRF2BP2 expression in hematopoietic and solid tumors through mechanisms based on gene fusion and point mutations in gene coding sequences, and although the biological functions of these types of hybrid and mutant proteins are not yet known, they are thought to be involved in an increase in the likelihood of tumor development. In this review, we address the possible involvement of IRF2BP2 in tumorigenesis through its regulation of important pathways involved in tumor development.

Expression, Prognosis and Gene Regulation Network of NFAT Transcription Factors in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. The nuclear factor of activated T cells (NFAT) family is implicated in tumorigenesis and progression in various types of cancer. However, little is known about their expression patterns, distinct prognostic values, and potential regulatory networks in NSCLC. In this study, we comprehensively analyzed the distinct expression and prognostic value of NFATs in NSCLC through various large databases, including the Oncomine, UCSC Xena Browser, UALCAN databases, Kaplan–Meier Plotter, cBioPortal, and Enrichr. In lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), NFAT1/2/4/5 mRNA expression levels were significantly decreased and NFAT3 mRNA expression level was significantly increased. The cBioPortal database analysis showed that the mRNA dysregulation was one of the single most important factors for NFAT alteration in LUAD and LUSC and that both LUAD and LUSC cases with the alterations in the mRNA expression of NFATs had significantly better overall survival (OS). High expression levels of NFAT1/2/4/5 were significantly associated with better OS in LUAD, whereas high NFAT3 expression led to a worse OS. Overexpression of NFAT1/2 predicted better OS in LUSC, whereas high NFAT5 expression led to a worse OS. The networks for NFATs and the 50 most frequently altered neighbor genes in LUAD and LUSC were also constructed. NFATs and genes significantly associated with NFAT mRNA expression in LUAD and LUSC were significantly enriched in the cGMP-dependent protein kinase and Wnt signaling pathways. These results showed that the NFAT family members displayed varying degrees of abnormal expressions, suggesting that NFATs may be therapeutic targets for patients with NSCLC. Aberrant expression of NFATs was found to be associated with OS in the patients with NSCLC; among NFATs, NFAT3/4 may be new biomarkers for the prognosis of LUAD. However, further studies are required to validate our findings.

Combined inhibition of ACK1 and AKT shows potential toward targeted therapy against KRAS-mutant non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) with Kirsten RAt Sarcoma 2 viral oncogene homolog (KRAS) mutation has become a clinical challenge in cancer treatment as KRAS-mutant tumors are often resistant to conventional anti-tumor therapies. Activated CDC42-associated kinase 1 (ACK1), an activator of protein kinase B (AKT), is a promising target for KRAS-mutant tumor therapy, but the downstream ACK1 signaling remains poorly understood. The aim of this study was to evaluate the effectiveness of combined ACK1/AKT inhibition on the proliferation, migration, invasion, and apoptosis of KRAS-mutant NSCLC cell lines (NCI-H23, NCI-H358, and A549). The cells were treated with an inhibitor of either ACK1 (dasatinib or sunitinib) or AKT (MK-2206 or GDC-0068), and the optimal concentrations of the two yielding synergistic tumor-killing effects were determined by applying the Chou-Talalay equation for drug combinations. We showed that combined administration of ACK1 and AKT inhibitors at the optimal concentrations effectively suppressed NSCLC cell viability and promoted apoptosis while inducing cell cycle arrest at the G2 phase. Moreover, NSCLC cell migration and invasion were inhibited by combined ACK1/AKT inhibition. These phenomena were associated with the reduced phosphorylation levels of ACK1 and AKT (at Ser473 and Thr308), as well as alterations in caspase-dependent apoptotic signaling. Collectively, our results demonstrate the promising therapeutic potential of combined ACK1/AKT inhibition as a strategy against KRAS-mutant NSCLC. Our findings provide the basis for the clinical translation of biological targeted drugs (ACK1 and AKT inhibitors) and their rational combination in cancer treatment.

Integrated analysis of lncRNA, miRNA and mRNA profiles reveals potential lncRNA functions during early HIV infection

Background

Long noncoding RNAs (lncRNAs) can regulate gene expression in a cis-regulatory fashion or as “microRNA sponges”. However, the expression and functions of lncRNAs during early human immunodeficiency virus (HIV) infection (EHI) remain unclear.

Methods

3 HAART-naive EHI patients and 3 healthy controls (HCs) were recruited in this study to perform RNA sequencing and microRNA (miRNA) sequencing. The expression profiles of lncRNAs, mRNAs and miRNAs were obtained, and the potential roles of lncRNAs were analysed based on discovering lncRNA cis-regulatory target mRNAs and constructing lncRNA–miRNA–mRNA competing endogenous RNA (ceRNA) networks. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on 175 lncRNA-associated differentially expressed (DE) mRNAs to investigate the potential functions of DE lncRNAs in ceRNA networks.

Results

A total of 242 lncRNAs, 1240 mRNAs and 21 mature known miRNAs were determined as differentially expressed genes in HAART-naive EHI patients compared to HCs. Among DE lncRNAs, 44 lncRNAs were predicted to overlap with 41 target mRNAs, and 107 lncRNAs might regulate their nearby DE mRNAs. Two DE lncRNAs might regulate their cis-regulatory target mRNAs BTLA and ZAP70, respectively, which were associated with immune activation. In addition, the ceRNA networks comprised 160 DE lncRNAs, 21 DE miRNAs and 175 DE mRNAs. Seventeen DE lncRNAs were predicted to regulate HIF1A and TCF7L2, which are involved in the process of HIV-1 replication. Twenty DE lncRNAs might share miRNA response elements (MREs) with FOS, FOSB and JUN, which are associated with both immune activation and HIV-1 replication.

Conclusions

This study revealed that lncRNAs might play a critical role in HIV-1 replication and immune activation during EHI. These novel findings are helpful for understanding of the pathogenesis of HIV infection and provide new insights into antiviral therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02802-9.

Regulation of Circular RNA CircNFATC3 in Cancer Cells Alters Proliferation, Migration, and Oxidative Phosphorylation

Circular RNAs were once considered artifacts of transcriptome sequencing but have recently been identified as functionally relevant in different types of cancer. Although there is still no clear main function of circRNAs, several studies have revealed that circRNAs are expressed in various eukaryotic organisms in a regulated manner often independent of their parental linear isoforms demonstrating conservation across species. circNFATC3, an abundant and uncharacterized circular RNA of exon 2 and 3 from NFATC3, was identified in transcriptomic data of solid tumors. Here we show that circNFATC3 gain- and loss-of-function experiments using RNAi-mediated circRNA silencing and circular mini vector-mediated overexpression of circularized constructs in breast and ovarian cancer cell lines affect molecular phenotypes. The knockdown of circNFATC3 induces a reduction in cell proliferation, invasion, migration, and oxidative phosphorylation. Gain-of-function of circNFATC3 in MDA-MB-231 and SK-OV-3 cells show a significant increase in cell proliferation, migration, and respiration. The above results suggest that circNFATC3 is a functionally relevant circular RNA in breast and ovarian cancer.

Small Extracellular Vesicles: A Novel Avenue for Cancer Management

Extracellular vesicles are small membrane particles derived from various cell types. EVs are broadly classified as ectosomes or small extracellular vesicles, depending on their biogenesis and cargoes. Numerous studies have shown that EVs regulate multiple physiological and pathophysiological processes. The roles of small extracellular vesicles in cancer growth and metastasis remain to be fully elucidated. As endogenous products, small extracellular vesicles are an ideal drug delivery platform for anticancer agents. However, several aspects of small extracellular vesicle biology remain unclear, hindering the clinical implementation of small extracellular vesicles as biomarkers or anticancer agents. In this review, we summarize the utility of cancer-related small extracellular vesicles as biomarkers to detect early-stage cancers and predict treatment outcomes. We also review findings from preclinical and clinical studies of small extracellular vesicle-based cancer therapies and summarize interventional clinical trials registered in the United States Food and Drug Administration and the Chinese Clinical Trials Registry. Finally, we discuss the main challenges limiting the clinical implementation of small extracellular vesicles and recommend possible approaches to address these challenges.

Isoform-Selective NFAT Inhibitor: Potential Usefulness and Development

Nuclear factor of activated T cells (NFAT), which is the pharmacological target of immunosuppressants cyclosporine and tacrolimus, has been shown to play an important role not only in T cells (immune system), from which their name is derived, but also in many biological events. Therefore, functional and/or structural abnormalities of NFAT are linked to the pathogenesis of diseases in various organs. The NFAT protein family consists of five isoforms, and each isoform performs diverse functions and has unique expression patterns in the target tissues. This diversity has made it difficult to obtain ideal pharmacological output for immunosuppressants that inhibit the activity of almost all NFAT family members, causing serious and wide-ranging side effects. Moreover, it remains unclear whether isoform-selective NFAT regulation can be achieved by targeting the structural differences among NFAT isoforms and whether this strategy can lead to the development of better drugs than the existing ones. This review summarizes the role of the NFAT family members in biological events, including the development of various diseases, as well as the usefulness of and problems associated with NFAT-targeting therapies, including those dependent on current immunosuppressants. Finally, we propose a novel therapeutic strategy based on the molecular mechanisms that enable selective regulation of specific NFAT isoforms.

The DEAD-box protein family of RNA helicases: sentinels for a myriad of cellular functions with emerging roles in tumorigenesis

DEAD-box RNA helicases comprise a family within helicase superfamily 2 and make up the largest group of RNA helicases. They are a profoundly conserved family of RNA-binding proteins, carrying a generic Asp-Glu-Ala-Asp (D-E-A-D) motif that gives the family its name. Members of the DEAD-box family of RNA helicases are engaged in all facets of RNA metabolism from biogenesis to decay. DEAD-box proteins ordinarily function as constituents of enormous multi-protein complexes and it is believed that interactions with other components in the complexes might be answerable for the various capacities ascribed to these proteins. Therefore, their exact function is probably impacted by their interacting partners and to be profoundly context dependent. This may give a clarification to the occasionally inconsistent reports proposing that DEAD-box proteins have both pro- and anti-proliferative functions in cancer. There is emerging evidence that DEAD-box family of RNA helicases play pivotal functions in various cellular processes and in numerous cases have been embroiled in cellular proliferation and/or neoplastic transformation. In various malignancy types, DEAD-box RNA helicases have been reported to possess pro-proliferation or even oncogenic roles as well as anti-proliferative or tumor suppressor functions. Clarifying the exact function of DEAD-box helicases in cancer is probably intricate, and relies upon the cellular milieu and interacting factors. This review aims to summarize the current data on the numerous capacities that have been ascribed to DEAD-box RNA helicases. It also highlights their diverse actions upon malignant transformation in the various tumor types.

Differentially methylated regions within lung cancer risk loci are enriched in deregulated enhancers

Genome-wide association studies (GWAS) have identified SNPs linked with lung cancer risk. Our aim was to discover the genes, non-coding RNAs, and regulatory elements within GWAS-identified risk regions that are deregulated in non-small cell lung carcinoma (NSCLC) to identify novel, clinically targetable genes and mechanisms in carcinogenesis. A targeted bisulphite-sequencing approach was used to comprehensively investigate DNA methylation changes occurring within lung cancer risk regions in 17 NSCLC and adjacent normal tissue pairs. We report differences in differentially methylated regions between adenocarcinoma and squamous cell carcinoma. Among the minimal regions found to be differentially methylated in at least 50% of the patients, 7 candidates were replicated in 2 independent cohorts (n = 27 and n = 87) and the potential of 6 as methylation-dependent regulatory elements was confirmed by functional assays. This study contributes to understanding the pathways implicated in lung cancer initiation and progression, and provides new potential targets for cancer treatment.

REL Domain of NFATc2 Binding to Five Types of DNA Using Protein Binding Microarrays

NFATc2 is a DNA binding protein in the Rel family transcription factors, which binds a CGGAA motif better when both cytosines in the CG dinucleotide are methylated. Using protein binding microarrays (PBMs), we examined the DNA binding of NFATc2 to three additional types of DNA: single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) with either 5-methylcytosine (5mC, M) or 5-hydroxymethylcytosine (5hmC, H) in one strand and a cytosine in the second strand. ATTTCCAC, the complement of the core GGAA motif, is better bound as ssDNA compared to dsDNA. dsDNA containing the 5-mer CGGAA with either 5mC or 5hmC in one DNA strand is bound stronger than CGGAA. In contrast, the reverse complement TTCCG is bound weaker when it contains 5mC. Analysis of the available NFATc2:dsDNA complexes rationalizes these PBM data.

AKT3 Expression in Mesenchymal Colorectal Cancer Cells Drives Growth and Is Associated with Epithelial-Mesenchymal Transition

Simple Summary

Colorectal cancer can be subdivided into four distinct subtypes that are characterised by different clinical features and responses to therapies currently used in the clinic to treat this disease. One of those subtypes, called CMS4, is associated with a worse prognosis and poor response to therapies compared to other subtypes. We therefore set out to explore what proteins are differentially expressed and used in CMS4 to find potential new targets for therapy. We found that protein AKT3 is highly expressed in CMS4, and that active AKT3 inhibits a protein that stalls growth of cancer cells (p27^KIP1). We can target AKT3 with inhibitors which leads to strongly reduced growth of cancer cell lines that are categorised as CMS4. Furthermore, our data suggests that high AKT3 expression in tumour cells may be used to identify poor prognosis colorectal cancer patients. Future research should point out if high AKT3 expression can be used to select colorectal cancer patients that have a poor prognosis but that could benefit from AKT3-targeted treatment.

Abstract

Colorectal cancer (CRC) is a heterogeneous disease that can currently be subdivided into four distinct consensus molecular subtypes (CMS) based on gene expression profiling. The CMS4 subtype is marked by high expression of mesenchymal genes and is associated with a worse overall prognosis compared to other CMSs. Importantly, this subtype responds poorly to the standard therapies currently used to treat CRC. We set out to explore what regulatory signalling networks underlie the CMS4 phenotype of cancer cells, specifically, by analysing which kinases were more highly expressed in this subtype compared to others. We found AKT3 to be expressed in the cancer cell epithelium of CRC specimens, patient derived xenograft (PDX) models and in (primary) cell cultures representing CMS4. Importantly, chemical inhibition or knockout of this gene hampers outgrowth of this subtype, as AKT3 controls expression of the cell cycle regulator p27^KIP1. Furthermore, high AKT3 expression was associated with high expression of epithelial-mesenchymal transition (EMT) genes, and this observation could be expanded to cell lines representing other carcinoma types. More importantly, this association allowed for the identification of CRC patients with a high propensity to metastasise and an associated poor prognosis. High AKT3 expression in the tumour epithelial compartment may thus be used as a surrogate marker for EMT and may allow for a selection of CRC patients that could benefit from AKT3-targeted therapy.

Novel partners of USP6 gene in a spectrum of bone and soft tissue lesions

Nodular fasciitis, primary aneurysmal bone cyst, myositis ossificans, and their related lesions are benign tumors that share common histological features and a chromosomal rearrangement involving the ubiquitin-specific peptidase 6 (USP6) gene. The identification of an increasing number of new partners implicated in USP6 rearrangements demonstrates a complex tumorogenesis of this tumor spectrum. In this study on a series of 77 tumors (28 nodular fasciitis, 42 aneurysmal bone cysts, and 7 myositis ossificans) from the database of the French Sarcoma Group, we describe 7 new partners of the USP6 gene. For this purpose, rearrangements were first researched by multiplexed RT-qPCRs in the entire population. A targeted RNA sequencing was then used on samples selected according to a high USP6-transcription level expression estimated by RT-qPCR. Thanks to this multistep approach, besides the common USP6 fusions observed, we detected novel USP6 partners: PDLIM7 and MYL12A in nodular fasciitis and TPM4, DDX17, GTF2I, KLF3, and MEF2A in aneurysmal bone cysts. In order to try to bring to light the role played by the recently identified USP6 partners in this lesional spectrum, their functions are discussed. Taking into account that a traumatic participation has long been mentioned in the histogenesis of most of these lesions and because of their morphological resemblance to organizing granulation reparative tissue or callus, a focus is placed on their relationship with tissue remodeling and, to a lesser extent, with bone metabolism.

NFAT5 Regulated by STUB1, Facilitates Malignant Cell Survival and p38 MAPK Activation by Upregulating AQP5 in Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is a clonal proliferative disease of mature B lymphocytes. To further improve the prognosis of patients, it is necessary to further elucidate the pathogenesis of CLL and find more effective therapeutic targets. Nuclear Factor of Activated T cells 5 (NFAT5) is the major activated transcription factor (TF) upon osmotic pressure increase in mammalian cells, and it also regulates many target genes to affect various cellular functions. The effects of NFAT5 on tumor growth and metastasis have also been widely revealed. However, the effects of NFAT5 on the progression of CLL are still unclear. In this study, we found abnormally high expression of NFAT5 in human CLL patients. Additionally, NFAT5 depletion suppressed proliferation and stimulated apoptosis of CLL cells. Our data further confirmed NFAT5 regulated AQP5 expression and the phosphorylation of p38 MAPK. We also found that AQP5 overexpression reversed the inhibitory effect of NFAT5 depletion on cell proliferation in CLL cells. Furthermore, we revealed STUB1 directly bound to NFAT5 and promoted its degradation. Taken together, our results indicate the involvement of NFAT5 in CLL progression and suggest that NFAT5 could serve as a promising therapeutic target for CLL treatment.

TonEBP regulates the hyperosmotic expression of aquaporin 1 and 5 in the intervertebral disc

The central region of the intervertebral disc (IVD) is rich in proteoglycans, leading to a hyperosmotic environment, which fluctuates with daily loading. The cells of the nucleus pulposus (NP cells) have adapted to this environment via the function of tonicity enhancer binding protein (TonEBP), and NP cells have been shown to express several water channels known as aquaporins (AQP). We have previously shown that AQP1 and 5 decrease during IVD degeneration. Here, the regulation of AQP1 and 5 by hyperosmotic conditions and the role of TonEBP in this regulation was investigated. AQP1 and 5 gene expression was upregulated by hyperosmotic conditions mimicking the osmolality of the healthy IVD, which was abrogated by TonEBP knockdown. Furthermore, AQP1 and 5 immunopositivity was significantly reduced in TonEBP^Δ/Δ E17.5 mice when compared with wildtype controls, indicating in vivo expression of AQP1 and 5 is controlled at least in part by TonEBP. This hyperosmotic regulation of AQP1 and 5 could help to explain the decreased AQP1 and 5 expression during degeneration, when the osmolality of the NP decreases. Together this data suggests that TonEBP-regulated osmo-adaptation may be disrupted during IVD degeneration when the expression of both AQPs is reduced.