Intertwining of Activin A and TGFβ Signaling: Dual Roles in Cancer Progression and Cancer Cell Invasion

Maternal malnutrition associated with postnatal sugar consumption increases inflammatory response and prostate disorders in rat offspring

Maternal malnutrition can alter developmental biology, programming health and disease in offspring. The increase in sugar consumption during the peripubertal period, a worldwide concern, also affects health through adulthood. Studies have shown that maternal exposure to a low protein diet (LPD) is associated with an increase in prostate disease with aging. However, the combined effects of maternal LPD and early postnatal sugar consumption on offspring prostate disorders were not investigated. The effects on aging were evaluated using a maternal gestational model with lactational LPD (6% protein) and sugar consumption (10%) from postnatal day (PND) 21-90, associating the consequences on ventral prostate (VP) rats morphophysiology on PND540. An increase was shown in mast cells and in the VP of the CTR + SUG and Gestational and Lactational Low Protein (GLLP) groups. In GLLP + SUG, a significant increase was shown in TGF-β1 expression in both the systemic and intra-prostatic forms, and SMAD2/3p had increased. The study identified maternal LPD and sugar consumption as risk factors for prostatic homeostasis in senility, activating the TGFβ1-SMAD2/3 pathway, a signaling pathway with potential markers for prostatic disorders.

Activin A levels are raised during human tuberculosis and blockade of the activin signaling axis influences murine responses to M. tuberculosis infection

Activin A strongly influences immune responses; yet, few studies have examined its role in infectious diseases. We measured serum activin A levels in two independent tuberculosis (TB) patient cohorts and in patients with pneumonia and sarcoidosis. Serum activin A levels were increased in TB patients compared to healthy controls, including those with positive tuberculin skin tests, and paralleled severity of disease, assessed by X-ray scores. In pneumonia patients, serum activin A levels were also raised, but in sarcoidosis patients, levels were lower. To determine whether blockade of the activin A signaling axis could play a functional role in TB, we harnessed a soluble activin type IIB receptor fused to human IgG1 Fc, ActRIIB-Fc, as a ligand trap in a murine TB model. The administration of ActRIIB-Fc to Mycobacterium tuberculosis-infected mice resulted in decreased bacterial loads and increased numbers of CD4 effector T cells and tissue-resident memory T cells in the lung. Increased frequencies of tissue-resident memory T cells corresponded with downregulated T-bet expression in lung CD4 and CD8 T cells. Altogether, the results suggest a disease-exacerbating role of ActRIIB signaling pathways. Serum activin A may be useful as a biomarker for diagnostic triage of active TB or monitoring of anti-tuberculosis therapy.

IMPORTANCE

Tuberculosis remains the leading cause of death by a bacterial pathogen. The etiologic agent of tuberculosis, Mycobacterium tuberculosis, can remain dormant in the infected host for years before causing disease. Significant effort has been made to identify biomarkers that can discriminate between latently infected and actively diseased individuals. We found that serum levels of the cytokine activin A were associated with increased lung pathology and could discriminate between active tuberculosis and tuberculin skin-test-positive healthy controls. Activin A signals through the ActRIIB receptor, which can be blocked by administration of the ligand trap ActRIIB-Fc, a soluble activin type IIB receptor fused to human IgG1 Fc. In a murine model of tuberculosis, we found that ActRIIB-Fc treatment reduced mycobacterial loads. Strikingly, ActRIIB-Fc treatment significantly increased the number of tissue-resident memory T cells. These results suggest a role for ActRIIB signaling pathways in host responses to Mycobacterium tuberculosis and activin A as a biomarker of ongoing disease.

MET exon 14 skipping mutation drives cancer progression and recurrence via activation of SMAD2 signalling

BACKGROUND

c-Met encoded by the proto-oncogene MET, also known as hepatocyte growth factor (HGF) receptor, plays a crucial role in cellular processes. MET exon 14 skipping alteration (METΔ14EX) is a newly discovered MET mutation. SMAD2 is an important downstream transcription factor in TGF-β pathway. Unfortunately, the mechanisms by which METΔ14EX leads to oncogenic transformation are scarcely understood. The relationship between METΔ14EX and SMAD2 has not been studied yet.

METHODS

We generate METΔ14EX models by CRISPR-Cas9. In vitro transwell, wound-healing, soft-agar assay, in vivo metastasis and subcutaneous recurrence assay were used to study the role of METΔ14EX in tumour progression. RNA-seq, Western blotting, co-immunoprecipitation (CO-IP) and immunofluorescent were performed to explore the interaction between c-Met and SMAD2.

RESULTS

Our results demonstrated that METΔ14EX, independent of HGF, can prolong the constitutive activation of c-Met downstream signalling pathways by impeding c-Met degradation and facilitating tumour metastasis and recurrence. Meanwhile, METΔ14EX strengthens the interaction between c-Met and SMAD2, promoting SMAD2 phosphorylation. Therapeutically, MET inhibitor crizotinib impedes METΔ14EX-mediated tumour metastasis by decreasing SMAD2 phosphorylation.

CONCLUSIONS

These data elucidated the previously unrecognised role of METΔ14EX in cancer progression via activation of SMAD2 independent of TGF-β, which helps to develop more effective therapies for such patients. METΔ14EX alteration significantly triggers tumour progression via activation of SMAD2 signalling that are involved in activating tumour invasion, metastasis and recurrence. On the left, in the MET wild-type (METWT), the juxtamembrane (JM) domain is involved in the regulation of tyrosine kinase activity, receptor degradation, and caspase cleavage. On the right, the METΔ14EX mutation leads to the loss of the juxtamembrane domain, resulting in an abnormal MET protein lacking a CBL-binding site. This causes the accumulation of truncated MET receptors followed by constitutive activation of the MET signalling pathway. Thus, the METΔ14EX-mutated protein has strong binding and phosphorylation to SMAD2, which results in the phosphorylation of a large number of SMAD2/3 proteins that combine with SMAD4 to form a complex in the nucleus, activating downstream signalling pathways, such as EMT and ECM remodelling, resulting in tumour progression and recurrence. TF transcription factor.

The Role of SOX2 and SOX9 in Radioresistance and Tumor Recurrence

Head and neck squamous cell carcinoma (HNSCC) exhibits considerable variability in patient outcome. It has been reported that SOX2 plays a role in proliferation, tumor growth, drug resistance, and metastasis in a variety of cancer types. Additionally, SOX9 has been implicated in immune tolerance and treatment failures. SOX2 and SOX9 induce treatment failure by a molecular mechanism that has not yet been elucidated. This study explores the inverse association of SOX2/SOX9 and their distinct expression in tumors, influencing the tumor microenvironment and radiotherapy responses. Through public RNA sequencing data, human biopsy samples, and knockdown cellular models, we explored the effects of inverted SOX2 and SOX9 expression. We found that patients expressing SOX2LowSOX9High showed decreased survival compared to SOX2HighSOX9Low. A survival analysis of patients stratified by radiotherapy and human papillomavirus brings additional clinical relevance. We identified a gene set signature comprising newly discovered candidate genes resulting from inverted SOX2/SOX9 expression. Moreover, the TGF-β pathway emerges as a significant predicted contributor to the overexpression of these candidate genes. In vitro findings reveal that silencing SOX2 enhances tumor radioresistance, while SOX9 silencing enhances radiosensitivity. These discoveries lay the groundwork for further studies on the therapeutic potential of transcription factors in optimizing HNSCC treatment.

Inhibition of anti-tumor immunity by melanoma cell-derived Activin-A depends on STING

The transforming growth factor-β (TGF-β) family member activin A (hereafter Activin-A) is overexpressed in many cancer types, often correlating with cancer-associated cachexia and poor prognosis. Activin-A secretion by melanoma cells indirectly impedes CD8+ T cell-mediated anti-tumor immunity and promotes resistance to immunotherapies, even though Activin-A can be proinflammatory in other contexts. To identify underlying mechanisms, we here analyzed the effect of Activin-A on syngeneic grafts of Braf mutant YUMM3.3 mouse melanoma cells and on their microenvironment using single-cell RNA sequencing. We found that the Activin-A-induced immune evasion was accompanied by a proinflammatory interferon signature across multiple cell types, and that the associated increase in tumor growth depended at least in part on pernicious STING activity within the melanoma cells. Besides corroborating a role for proinflammatory signals in facilitating immune evasion, our results suggest that STING holds considerable potential as a therapeutic target to mitigate tumor-promoting Activin-A signaling at least in melanoma.

Potential Roles of Activin in Head and Neck Squamous Cell Carcinoma Progression and Mortality

BACKGROUND/AIM

Activin, a member of the TGF-β super family of cytokines, is involved in head and neck squamous cell carcinoma (HNSCC). This study examined the constituents of the activin axis in order to further elucidate the role of activin A in HNSCC progression.

MATERIALS AND METHODS

Immunohistochemistry (IHC), reverse transcription polymerase chain reaction (RT-PCR), MTT, and matrigel invasion assays, in addition to analysis of the tumor cancer genome atlas (TCGA), were employed.

RESULTS

IHC in HNSCC and oral leukoplakia (OPL) lesions demonstrated increased expression of the inhibin subunit βA (INHBA) (p<0.0001), as well as activin receptor type IB (ACVR1B) (p<0.0032) compared to normal mucosa. TCGA analysis revealed increased INHBA expression was associated with lymph node positive tumors (p=0.024), decreased overall survival (p=0.0167), and decreased promoter methylation (p<0.0001). Concomitant up-regulated expression of gene pathways strongly correlated with INHBA expression demonstrated further deleterious effects on survival (p<0.0148).

CONCLUSION

Activin may be an important component of early carcinogenesis in OPL and HNSCC with unfavorable effects on clinical end-points such as survival.

Clinicopathological and prognostic significance of SMAD4 in non-small cell lung cancer: A meta-analysis and database validation

BACKGROUND

The relationship between SMAD family member 4 (SMAD4) and the clinicopathological and prognostic significance of non-small cell lung cancer (NSCLC) patients is unclear. Our aim was to investigate the association between SMAD4 expression and clinicopathological parameters and NSCLC prognosis.

METHODS

We searched articles in databases from inception to July 2022 to retrieve literature related to SMAD4 expression and the clinicopathological and/or prognostic significance of NSCLC patients. Odds ratios (ORs), hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. We evaluated the expression of SMAD4 and overall survival (OS) in NSCLC using the Kaplan-Meier plotter database.

RESULTS

Eight articles with 1461 NSCLC patients were included. SMAD4 expression was related to tumor differentiation (OR = 0.359, 95% CI: 0.238-0.543, P = .000), lymph node metastasis (OR = 0.469, 95% CI: 0.04-0.725, P = .001), tumor node metastasis stage (OR = 0.238, 95% CI: 0.156-0.362, P = .000) and good OS (HR = 0.592, 95% CI: 0.332-0.853, P = .000) in NSCLC. There was no significant association between SMAD4 expression and age (OR = 0.822, 95% CI: 0.515-1.312, P = .411) or sex (OR = 1.056, 95% CI: 0.675-1.653, P = .811). Furthermore, SMAD4 expression was lower in NSCLC, and a good prognosis in NSCLC (HR = 0.6, 95% CI = 0.51-0.72, P = 4.2 e-9) was shown to correlate with higher SMAD4 expression using the Kaplan-Meier Plotter database.

CONCLUSION

SMAD4 expression is lower in NSCLC and correlated with lymph node metastasis, tumor differentiation, tumor node metastasis stage and good OS for NSCLC patients.

Embryo-derive TNF promotes decidualization via fibroblast activation

Decidualization is a process in which endometrial stromal fibroblasts differentiate into specialized secretory decidual cells and essential for the successful establishment of pregnancy. The underlying mechanism during decidualization still remains poorly defined. Because decidualization and fibroblast activation share similar characteristics, this study was to examine whether fibroblast activation is involved in decidualization. In our study, fibroblast activation-related markers are obviously detected in pregnant decidua and under in vitro decidualization. ACTIVIN A secreted under fibroblast activation promotes in vitro decidualization. We showed that arachidonic acid released from uterine luminal epithelium can induce fibroblast activation and decidualization through PGI₂ and its nuclear receptor PPARδ. Based on the significant difference of fibroblast activation-related markers between pregnant and pseudopregnant mice, we found that embryo-derived TNF promotes CPLA_2α phosphorylation and arachidonic acid release from luminal epithelium. Fibroblast activation is also detected under human in vitro decidualization. Similar arachidonic acid-PGI₂-PPARδ-ACTIVIN A pathway is conserved in human endometrium. Collectively, our data indicate that embryo-derived TNF promotes CPLA_2α phosphorylation and arachidonic acid release from luminal epithelium to induce fibroblast activation and decidualization.

Uncovering Tumor-Promoting Roles of Activin A in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with high incidence rates of metastasis and cachexia. High circulating activin A, a homodimer of inhibin βA subunits that are encoded by INHBA gene, predicts poor survival among PDAC patients. However, it still raises the question of whether activin A suppression renders favorable PDAC outcomes. Here, the authors demonstrate that activin A is abundantly detected in tumor and stromal cells on PDAC tissue microarray and mouse PDAC sections. In orthotopic male mice, activin A suppression, which is acquired by tumor-targeted Inhba siRNA using cholesterol-modified polymeric nanoparticles, retards tumor growth/metastasis and cachexia and improves survival when compared to scramble siRNA-treated group. Histologically, activin A suppression coincides with decreased expression of proliferation marker Ki67 but increased accumulation of α-SMAhigh fibroblasts and cytotoxic T cells in the tumors. In vitro data demonstrate that activin A promotes KPC cell proliferation and induces the downregulation of α-SMA and upregulation of IL-6 in pancreatic stellate cells (PSC) in the SMAD3-dependent mechanism. Moreover, conditioned media from activin A-stimulated PSC promoted KPC cell growth. Collectively, our data provide a mechanistic basis for tumor-promoting roles of activin A and support therapeutic potentials of tumor activin A suppression for PDAC.

Immunostaining of βA-Activin and Follistatin Is Decreased in HPV(+) Cervical Pre-Neoplastic and Neoplastic Lesions

The activin-follistatin system regulates several cellular processes, including differentiation and tumorigenesis. We hypothesized that the immunostaining of βA-activin and follistatin varies in neoplastic cervical lesions. Cervical paraffin-embedded tissues from 162 patients sorted in control (n = 15), cervical intraepithelial neoplasia (CIN) grade 1 (n = 38), CIN2 (n = 37), CIN3 (n = 39), and squamous cell carcinoma (SCC; n = 33) groups were examined for βA-activin and follistatin immunostaining. Human papillomavirus (HPV) detection and genotyping were performed by PCR and immunohistochemistry. Sixteen samples were inconclusive for HPV detection. In total, 93% of the specimens exhibited HPV positivity, which increased with patient age. The most detected high-risk (HR)-HPV type was HPV16 (41.2%) followed by HPV18 (16%). The immunostaining of cytoplasmatic βA-activin and follistatin was higher than nuclear immunostaining in all cervical epithelium layers of the CIN1, CIN2, CIN3, and SCC groups. A significant decrease (p < 0.05) in the cytoplasmic and nuclear immunostaining of βA-activin was detected in all cervical epithelial layers from the control to the CIN1, CIN2, CIN3, and SCC groups. Only nuclear follistatin immunostaining exhibited a significant reduction (p < 0.05) in specific epithelial layers of cervical tissues from CIN1, CIN2, CIN3, and SCC compared to the control. Decreased immunostaining of cervical βA-activin and follistatin at specific stages of CIN progression suggests that the activin-follistatin system participates in the loss of the differentiation control of pre-neoplastic and neoplastic cervical specimens predominantly positive for HPV.

Inactivating the Uninhibited: The Tale of Activins and Inhibins in Pulmonary Arterial Hypertension

Advances in technology and biomedical knowledge have led to the effective diagnosis and treatment of an increasing number of rare diseases. Pulmonary arterial hypertension (PAH) is a rare disorder of the pulmonary vasculature that is associated with high mortality and morbidity rates. Although significant progress has been made in understanding PAH and its diagnosis and treatment, numerous unanswered questions remain regarding pulmonary vascular remodeling, a major factor contributing to the increase in pulmonary arterial pressure. Here, we discuss the role of activins and inhibins, both of which belong to the TGF-β superfamily, in PAH development. We examine how these relate to signaling pathways implicated in PAH pathogenesis. Furthermore, we discuss how activin/inhibin-targeting drugs, particularly sotatercep, affect pathophysiology, as these target the afore-mentioned specific pathway. We highlight activin/inhibin signaling as a critical mediator of PAH development that is to be targeted for therapeutic gain, potentially improving patient outcomes in the future.

Exploration the role of INHBA in Hu sheep granulosa cells using RNA-Seq

Activin/inhibin is an important factor for the fecundity of Hu sheep, and it is involved in follicular development in ovaries. Inhibin subunit beta A (INHBA) participates in the synthesis of activin A and inhibin A. In this study, we also noted a positive correlation between INHBA level and the secretion of both activin A and inhibin A in culture medium. Nevertheless, both knockdown and overexpression of INHBA downregulated the expression of Inhibin Subunit Alpha (INHA). Based on RNA-Sequencing, we further examined the effect and molecular mechanism of INHBA knockdown in GCs on mRNA expression. A total of 1,687 differentially expressed genes (DEGs) were identified (Fold change ≥ 2; False-discovory-rates (FDR) ≤ 0.01), of which 602 genes were upregulated and 1,087 genes were downregulated in the INHBA interference group compared with the control groups. Gene Ontology (GO) enrichment indicated that these DEGs were mainly involved in the regulation of cell cycle, protein serine/threonine kinase activity, and actin cytoskeleton reorganization. Moreover, DEGs were significantly enriched in 40 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including P53, progesterone-mediated oocyte maturation, and PI3K-AKT signaling pathways. We also noted a positive correlation between INHBA level and many PI3K/Akt/mTOR pathway-related genes at the gene or/and protein expression. Overall, this study may contribute to a better understanding of the roles of INHBA on GCs of prolific sheep, as well as the molecular effect of low INHBA expression on GCs, clarifying some reproductive failures.

CoQ10 reduces glioblastoma growth and infiltration through proteome remodeling and inhibition of angiogenesis and inflammation

PURPOSE

Most monotherapies available against glioblastoma multiforme (GBM) target individual hallmarks of this aggressive brain tumor with minimal success. In this article, we propose a therapeutic strategy using coenzyme Q10 (CoQ10) as a pleiotropic factor that crosses the blood-brain barrier and accumulates in cell membranes acting as an antioxidant, and in mitochondrial membranes as a regulator of cell bioenergetics and gene expression.

METHODS

Xenografts of U251 cells in nu/nu mice were used to assay tumor growth, hypoxia, angiogenesis, and inflammation. An orthotopic model was used to explore microglial infiltration, tumor growth, and invasion into the brain parenchyma. Cell proliferation, migration, invasion, proteome remodeling, and secretome were assayed in vitro. Conditioned media were used to assay angiogenesis, monocyte chemoattraction, and differentiation into macrophages in vitro.

RESULTS

CoQ10 treatment decreased tumor volume in xenografts and orthotopic models, although its effect on tumor cell proliferation was not direct. Tumors from mice treated with CoQ10 were less hypoxic and vascularized, having less infiltration from inflammatory cells. Treatment-induced downregulation of HIF-1α and NF-kB led to a complete remodeling of the tumor cells proteome and secretome, impacting angiogenesis, monocyte infiltration, and their differentiation into macrophages. Besides, tumor cell migration and invasion were drastically restricted by mechanisms involving modulation of the actin cytoskeleton and downregulation of matrix metalloproteases (MMPs).

CONCLUSIONS

CoQ10 has a pleiotropic effect on GBM growth, targeting several hallmarks simultaneously. Thus, its integration into current treatments of this fatal disease should be considered.

EBV dUTPase: A Novel Modulator of Inflammation and the Tumor Microenvironment in EBV-Associated Malignancies

There is increasing evidence that put into question the classical dogma that the Epstein-Barr virus (EBV) exists in cells as either a lytic virus in which new progeny is produced or in a latent state in which no progeny is produced. Notably, a third state has now been described, known as the abortive-lytic phase, which is characterized by the expression of some immediate early (IE) and early (E) genes, but no new virus progeny is produced. While the function of these IE and E gene products is not well understood, several recent studies support the concept they may contribute to tumor promotion by altering the tumor microenvironment (TME). The mechanisms by which these viral gene products may contribute to tumorigenesis remain unclear; however, it has been proposed that some of them promote cellular growth, immune evasion, and/or inhibit apoptosis. One of these EBV early gene products is the deoxyuridine triphosphate nucleotidohydrolase (dUTPase) encoded by BLLF3, which not only contributes to the establishment of latency through the production of activin A and IL-21, but it may also alter the TME, thus promoting oncogenesis.

Activin B and Activin C Have Opposing Effects on Prostate Cancer Progression and Cell Growth

Current prognostic and diagnostic tests for prostate cancer are not able to accurately distinguish between aggressive and latent cancer. Members of the transforming growth factor-β (TGFB) family are known to be important in regulating prostate cell growth and some have been shown to be dysregulated in prostate cancer. Therefore, the aims of this study were to examine expression of TGFB family members in primary prostate tumour tissue and the phenotypic effect of activins on prostate cell growth. Tissue cores of prostate adenocarcinoma and normal prostate were immuno-stained and protein expression was compared between samples with different Gleason grades. The effect of exogenous treatment with, or overexpression of, activins on prostate cell line growth and migration was examined. Activin B expression was increased in cores containing higher Gleason patterns and overexpression of activin B inhibited growth of PNT1A cells but increased growth and migration of the metastatic PC3 cells compared to empty vector controls. In contrast, activin C expression decreased in higher Gleason grades and overexpression increased growth of PNT1A cells and decreased growth of PC3 cells. In conclusion, increased activin B and decreased activin C expression is associated with increasing prostate tumor grade and therefore have potential as prognostic markers of aggressive prostate cancer.

A critical ETV4/Twist1/Vimentin axis in Ha-RAS-induced aggressive breast cancer

RAS oncogenes are major drivers of diverse types of cancer. However, they are largely not druggable, and therefore targeting critical downstream pathways and dependencies is an attractive approach. We have isolated a tumorigenic cell line (FE1.2), which exhibits mesenchymal characteristics, after inoculating Ha-Ras-expressing retrovirus into mammary glands of rats, and subsequently isolated a non-aggressive revertant cell line (FC5). This revertant has lost the rat Ha-Ras driver and showed a more epithelial morphology, slower proliferation in culture, and reduced tumorigenicity in vivo. Re-expression of human Ha-RAS in these cells (FC5-RAS) reinduced mesenchymal morphology, higher proliferation rate, and tumorigenicity that was still significantly milder than parental FE1.2 cells. RNA-seq analysis of FC5-RAS vs FC5-Vector cells identified multiple genes whose expressions were regulated by Ha-RAS. This analysis also identified many genes including those controlling cell growth whose expression was altered by loss of HA-Ras in FC5 cells but remained unchanged upon reintroduction of Ha-RAS. These results suggest that targeting the Ha-Ras driver oncogene induces partial tumor regression, but it still denotes strong efficacy for cancer therapy. Among the RAS-responsive genes, we identified Twist1 as a critical mediator of epithelial-to-mesenchymal transition through the direct transcriptional regulation of vimentin. Mechanistically, we show that Twist1 is induced by the ETS gene, ETV4, downstream of Ha-RAS, and that inhibition of ETV4 suppressed the growth of breast cancer cells driven by the Ha-RAS pathway. Targeting the ETV4/Twist1/Vimentin axis may therefore offer a therapeutic modality for breast tumors driven by the Ha-RAS pathway.

Bone morphogenetic proteins, activins, and growth and differentiation factors in tumor immunology and immunotherapy resistance

The TGF-β superfamily is a group of secreted polypeptides with key roles in exerting and regulating a variety of physiologic effects, especially those related to cell signaling, growth, development, and differentiation. Although its central member, TGF-β, has been extensively reviewed, other members of the family-namely bone morphogenetic proteins (BMPs), activins, and growth and differentiation factors (GDFs)-have not been as thoroughly investigated. Moreover, although the specific roles of TGF-β signaling in cancer immunology and immunotherapy resistance have been extensively reported, little is known of the roles of BMPs, activins, and GDFs in these domains. This review focuses on how these superfamily members influence key immune cells in cancer progression and resistance to treatment.

Cytomegalovirus microRNAs level determination in kidney recipients post transplantation

BACKGROUND

Human cytomegalovirus (CMV) can establish a latent infection with periodic or sporadic reactivation after the first infection happens. Primary and recurrent infection, results in different problems in patients with impaired or immature immune systems, such as kidney transplant recipients (KTRs). MicroRNAs (miRNAs, miRs) are important regulatory molecules in the outcome of CMV-infected KTRs. Therefore, in this study the expression level of CMV miRNAs were evaluated in active vs. latent CMV infected KTRs.

METHODS

Expression of viral miRNAs were studied in 61 KTRs which were divided into 30 active CMV and 31 latent CMV infected individuals. In order to study the expression level of selected miRNAs, SYBR Green Real-time PCR technique was exploited. Also, mature miRNAs expression level that were produced from one precursor, studied both in active and latent situations.

RESULTS

Among studied miRNAs' expression level, CMV miR-UL112-3p/5p, -UL22A-3p/5p, -US25-1-5p, -US25-2-3p/5p, -UL36-3p/5p and -UL70-3p showed significant increase in active CMV infected KTRs in comparison to latent ones. The ROC curve analysis results for miR-UL112-3p, -UL22A-3p, -US25-2-3p, -UL36-3p and -UL70-3p showed significant difference between two studied patient groups.

CONCLUSION

This study revealed an extremely high expression level in CMV miR-UL112-3p/5p, -UL22A-3p/5p, -US25-1-5p, -US25-2-3p/5p, -UL36-3p/5p and -UL70-3p in active CMV infected KTRs in comparison to latent ones. Further studies might help in finding the capability of miRNAs to differentiate active from latent stage of CMV infection in KTRs.

Prognostic impact of activin subunit inhibin beta A in gastric and esophageal adenocarcinomas

PURPOSE

Adenocarcinomas of the esophagus (AEG) and stomach (AS) are among the most common cancers worldwide. Novel markers for risk stratification and guiding treatment are strongly needed. Activin is a multi-functional cytokine with context specific pro- and anti-tumorigenic effects. We aimed to investigate the prognostic role of activin tumor protein expression in AEG/ASs.

METHODS

Tissue from a retrospective cohort of 277 patients with AEG/AS treated primarily by surgery at the Charité - Universitätsmedizin Berlin was collected and analyzed by immunohistochemistry using a specific antibody to the activin homodimer inhibin beta A. Additionally, we evaluated T-cell infiltration and PD1 expression as well as expression of PD-L1 by immunohistochemistry as possible confounding factors. Clinico-pathologic data were collected and correlated with activin protein expression.

RESULTS

Out of 277 tumor samples, 72 (26.0%) exhibited high activin subunit inhibin beta A protein expression. Higher expression was correlated with lower Union for International Cancer Control (UICC) stage and longer overall survival. Interestingly, activin subunit expression correlated with CD4+ T-cell infiltration, and the correlation with higher overall survival was exclusively seen in tumors with high CD4+ T-cell infiltration, pointing towards a role of activin in the tumor immune response in AEG/ASs.

CONCLUSION

In our cohort of AEG/AS, higher activin subunit levels were correlated with longer overall survival, an effect exclusively seen in tumors with high CD4+ cell infiltration. Further mechanistic research is warranted discerning the exact effect of this context specific cytokine.

Gene Mutational Clusters in the Tumors of Colorectal Cancer Patients With a Family History of Cancer

Introduction

Family history is a high-risk factor for colorectal cancer (CRC). The risk comes not only from known germline mutations but also from the other family-related mechanisms. Uncovering them would be an important step to improve the diagnosis and treatment of these patients.

Method

Samples from 168 patients with advanced CRC were collected and applied to next-generation sequencing of 624 pan-cancer genes. Genomic mutations and significantly mutated genes were identified. Significantly mutated genes and co-mutated genes were used to cluster patients. For each cluster of patients, mutational signatures were extracted. The identified mutational signatures were further validated in the other independent cohort.

Result

Significantly mutated genes including TP53, APC, KRAS, and SMAD4 were found associated with tumor mutational burden and microsatellite instability. LRP1, ACVR2A, and SETBP1 were found co-mutated. Patients with mutations in LRP1, ACVR2A, and SETBP1 tend to have a family history of cancer. Those patients tended to have right-sided tumors with high tumor mutational burden and microsatellite instability. Among them, signature analysis identified two possible etiologies, SBS10a (defective polymerase epsilon exonuclease domain) and SBS6 (defective DNA mismatch repair and microsatellite unstable tumors). These signatures were also found in another independent cohort.

Conclusion

The gene cluster (LRP1, ACVR2A, and SETBP1) could be a good biomarker of these patients with a family risk, which was characterized by right-sidedness, high tumor mutational burden, and high microsatellite instability.

INHBA is a mediator of aggressive tumor behavior in HER2+ basal breast cancer

Background

Resistance to HER2-targeted therapeutics remains a significant clinical problem in HER2+ breast cancer patients with advanced disease. This may be particularly true for HER2+ patients with basal subtype disease, as recent evidence suggests they receive limited benefit from standard of care HER2-targeted therapies. Identification of drivers of resistance and aggressive disease that can be targeted clinically has the potential to impact patient outcomes.

Methods

We performed siRNA knockdown screens of genes differentially expressed between lapatinib-responsive and -resistant HER2+ breast cancer cells, which corresponded largely to luminal versus basal subtypes. We then validated hits in 2-d and 3-d cell culture systems.

Results

Knockdown of one of the genes, INHBA, significantly slowed growth and increased sensitivity to lapatinib in multiple basal HER2+ cell lines in both 2-d and 3-d cultures, but had no effect in luminal HER2+ cells. Loss of INHBA altered metabolism, eliciting a shift from glycolytic to oxidative phosphorylative metabolism, which was also associated with a decrease in tumor invasiveness. Analysis of breast cancer datasets showed that patients with HER2+ breast cancer and high levels of INHBA expression had worse outcomes than patients with low levels of INHBA expression.

Conclusions

Our data suggest that INHBA is associated with aggressiveness of the basal subtype of HER2+ tumors, resulting in poor response to HER2-targeted therapy and an invasive phenotype. We hypothesize that targeting this pathway could be an effective therapeutic strategy to reduce invasiveness of tumor cells and to improve therapeutic response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-022-01512-4.

Activin A Sustains the Metastatic Phenotype of Tumor-Associated Macrophages and Is a Prognostic Marker in Human Cutaneous Melanoma

Tumor cells attract and dynamically interact with monocytes/macrophages to subvert their differentiation into tumor-associated macrophages (TAMs), which mainly promote immune suppression and neoplastic progression, but the pathways and microenvironmental cues governing their protumoral deviation are not completely understood. To identify the molecular pathways responsible for TAM differentiation, we screened the biomarkers secreted during melanoma‒macrophage interactions using Quantibody microarrays and RNA sequencing of macrophages. We found that activin A, a member of the transforming GF family, plays an instrumental role in the cross-talk between melanoma cells and monocytes/macrophages, which results in the upregulation of distinct tumor-sustaining genes and the achievement of proinvasive and immunosuppressive functions of TAMs. Blockade of activin reduces the upregulation of part of these genes and prevents the acquisition of protumoral functions, facilitating human melanoma rejection by transferred human lymphocytes in a xenograft mouse model. Remarkably, screening of two independent cutaneous primary melanoma collections showed that activin A is enriched in TAMs and melanoma cells from patients with worse outcomes and constitutes a new and independent prognostic marker. Thus, we identify activin A as a key intermediary in the protumoral and immunosuppressive functions of TAMs, with significant potential as a disease biomarker as well as an immunotherapeutic target.

Anti-Metastatic Function of Extracellular Vesicles Derived from Nanog-Overexpressing Melanoma

A metastatic melanoma cell line B16-F10 (F10) was modified to a more undifferentiated state by Nanog overexpression. The produced cell line Nanog⁺F10 showed a higher metastatic potential than F10. Instead of whole cells, the extracellular vesicles (EVs) therefrom were investigated about their possible role as an autovaccine against metastasis. EVs from Nanog⁺F10 cells (Nanog⁺F10-EVs) could suppress the metastasis, contrasting the EVs from less metastatic F10 cells (F10-EVs) enhanced metastasis. The involvement of TGF-β1 in the role of Nanog⁺F10-EVs was analyzed, as TGF-β1 was a secretory cytokine being affected most intensively by Nanog overexpression. It was suggested to be crucial that the TGF-β1 concentration in Nanog⁺F10-EVs should be as low as 1.6 pg/μg for its metastasis-suppressive role. In response to Nanog⁺F10-EVs, immunoreaction was observed in liver, indicating the specific decrease in the number of tumor-promotive CD163-positive macrophages. These indicate a possibility of Nanog⁺F10-EVs as a novel autovaccine candidate against melanoma metastasis.

INHBA is a Prognostic Biomarker and Correlated With Immune Cell Infiltration in Cervical Cancer

Background: Inhibin A (INHBA), a member of the TGF-β superfamily, has been shown to be differentially expressed in various cancer types and is associated with prognosis. However, its role in cervical cancer remains unclear.

Methods: We aimed to demonstrate the relationship between INHBA expression and pan-cancer using The Cancer Genome Atlas (TCGA) database. Next, we validated INHBA expression in cervical cancer using the Gene Expression Omnibus (GEO) database, including GSE7803, GSE63514, and GSE9750 datasets. Enrichment analysis of INHBA was performed using the R package “clusterProfiler.” We analyzed the association between immune infiltration level and INHBA expression in cervical cancer using the single-sample gene set enrichment analysis (ssGSEA) method by the R package GSVA. We explored the association between INHBA expression and prognosis using the R package “survival”.

Results: Pan-cancer data analysis showed that INHBA expression was elevated in 19 tumor types, including cervical cancer. We further confirmed that INHBA expression was higher in cervical cancer samples from GEO database and cervical cancer cell lines than in normal cervical cells. Survival prognosis analysis indicated that higher INHBA expression was significantly associated with reduced Overall Survival (p = 0.001), disease Specific Survival (p = 0.006), and Progression Free Interval (p = 0.001) in cervical cancer and poorer prognosis in other tumors. GSEA and infiltration analysis showed that INHBA expression was significantly associated with tumor progression and some types of immune infiltrating cells.

Conclusion:INHBA was highly expressed in cervical cancer and was significantly associated with poor prognosis. Meanwhile, it was correlated with immune cell infiltration and could be used as a promising prognostic target for cervical cancer.

Profiling Activins and Follistatin in Colorectal Cancer According to Clinical Stage, Tumour Sidedness and Smad4 Status

This study explored the roles of activins and follistatin in colorectal cancers. Paired malignant and normal colonic tissues were collected from archived paraffin-embedded (n = 90 patients) alongside fresh (n = 40 patients) specimen cohorts. Activin β-subunits, follistatin and Smad4 mRNAs and proteins were measured by real-time PCR and immunohistochemistry (IHC). Mature activin-A, -B, -AB and follistatin proteins were measured by ELISA. Cancer tissues having ≤ the 20th percentile of the Smad4 IHC score were considered as low (L-S4) group. The Smad4-intact SW480 and Smad4-null HT29 colon cancer cell lines were treated with activins and follistatin, and cell cycle was analysed by flow cytometry. The cell cycle inducing (CCND1/CCND3) and inhibitory (p21/p27) proteins alongside the survival (survivin/BCL2) and pro-apoptosis (Casp-8/Casp-3) markers were measured by immunofluorescence. Thirty-nine patients had right-sided cancers (30%) and showed higher rates of L-S4 tumours (n = 17; 13.1%) alongside worse clinicopathological characteristics relative to left-sided cancers. The βA-subunit and activin-A increased, whilst βB-subunit and activin-AB decreased, in malignant sites and the late-stage cancers revealed the greatest abnormalities. Interestingly, follistatin declined markedly in early-stage malignant tissues, whilst increased significantly in the advanced stages. All activin molecules were comparable between the early stage right- and left-sided tumours, whereas the late-stage right-sided cancers and L-S4 tumours showed more profound deregulations. In vitro, activin-A increased the numbers of the SW480 cells in sub-G1 and G0/G1-phases, whereas reduced the HT29 cell numbers in the sub-G1 phase with simultaneous increases in the G0/G1 and S phases. The p21/p27/Casp-8/Casp-3 proteins escalated, whilst CCND1/CCND3/BCL2/survivin declined in the SW480 cells following activin-A, whereas activin-A only promoted p21 and p27 alongside reduced CCND3 in the HT29 cells. By contrast, activin-AB increased the numbers of SW480 and HT29 cells in Sub-G1 and G0/G1-phases and promoted the anti-cancer and reduced the oncogenic proteins in both cell lines. In conclusion, activins and follistatin displayed stage-dependent dysregulations and were markedly altered during the advanced stages of right-sided and L-S4 cancers. Moreover, the activin-A actions in CRC could be Smad4-dependent, whereas activin-AB may act as a Smad4-independent tumour suppressor protein.

Clinical relevance of circulating activin A and follistatin in small cell lung cancer

OBJECTIVES

Circulating levels of activin A (ActA) and follistatin (FST) have been investigated in various disorders including malignancies. However, to date, their diagnostic and prognostic relevance is largely unknown in small cell lung cancer (SCLC). Our aim was to evaluate circulating ActA and FST levels as potential biomarkers in this devastating disease.

METHODS

Seventy-nine Caucasian SCLC patients and 67 age- and sex-matched healthy volunteers were included in this study. Circulating ActA and FST concentrations were measured by ELISA and correlated with clinicopathological parameters and long-term outcomes.

RESULTS

Plasma ActA and FST concentrations were significantly elevated in SCLC patients when compared to healthy volunteers (p < 0.0001). Furthermore, extensive-stage SCLC patients had significantly higher circulating ActA levels than those with limited-stage disease (p = 0.0179). Circulating FST concentration was not associated with disease stage (p = 0.6859). Notably, patients with high (≥548.8 pg/ml) plasma ActA concentration exhibited significantly worse median overall survival (OS) compared to those with low (<548.8 pg/ml) ActA levels (p = 0.0009). Moreover, Cox regression analysis adjusted for clinicopathological parameters revealed that high ActA concentration is an independent predictor of shorter OS (HR: 1.932; p = 0.023). No significant differences in OS have been observed with regards to plasma FST levels (p = 0.1218).

CONCLUSION

Blood ActA levels are elevated and correlate with disease stage in SCLC patients. Measurement of circulating ActA levels might help in the estimation of prognosis in patients with SCLC.

KDM6A Regulates Cell Plasticity and Pancreatic Cancer Progression by Noncanonical Activin Pathway

BACKGROUND & AIMS

Inactivating mutations of KDM6A, a histone demethylase, were frequently found in pancreatic ductal adenocarcinoma (PDAC). We investigated the role of KDM6A (lysine demethylase 6A) in PDAC development.

METHODS

We performed a pancreatic tissue microarray analysis of KDM6A protein levels. We used human PDAC cell lines for KDM6A knockout and knockdown experiments. We performed bromouridine sequencing analysis to elucidate the effects of KDM6A loss on global transcription. We performed studies with Ptf1a^Cre; LSL-Kras^G12D; Trp53^R172H/+; Kdm6a^{fl/fl or fl/Y}, Ptf1a^Cre; Kdm6a^{fl/fl or fl/Y}, and orthotopic xenograft mice to investigate the impacts of Kdm6a deficiency on pancreatic tumorigenesis and pancreatitis.

RESULTS

Loss of KDM6A was associated with metastasis in PDAC patients. Bromouridine sequencing analysis showed up-regulation of the epithelial-mesenchymal transition pathway in PDAC cells deficient in KDM6A. Loss of KDM6A promoted mesenchymal morphology, migration, and invasion in PDAC cells in vitro. Mechanistically, activin A and subsequent p38 activation likely mediated the role of KDM6A loss. Inhibiting either activin A or p38 reversed the effect. Pancreas-specific Kdm6a-knockout mice pancreata showed accelerated PDAC progression, developed a more aggressive undifferentiated type of PDAC, and increased metastases in the background of Kras and p53 mutations. Kdm6a-deficient pancreata in a pancreatitis model had a delayed recovery with increased PDAC precursor lesions compared with wild-type pancreata.

CONCLUSIONS

Loss of KDM6A accelerates PDAC progression and metastasis, most likely by a noncanonical p38-dependent activin A pathway. KDM6A also promotes pancreatic tissue recovery from pancreatitis. Activin A might be used as a therapeutic target for KDM6A-deficient PDACs.

Inhibin βA is an independent prognostic factor that promotes invasion via Hippo signaling in non‑small cell lung cancer

Inhibin βA (INHBA) serves a prognostic and tumor-promoting role in numerous types of cancer. The present study aimed to determine the clinical significance of INHBA in non-small cell lung cancer (NSCLC) and the mechanisms underlying its potential tumor-promoting effect. INHBA expression was detected in clinical NSCLC samples using immunohistochemistry. In vivo loss- and gain-of-function studies were performed to determine the effects of INHBA on NSCLC invasion. In addition, protein and mRNA expression levels of INHBA, yes-associated protein (YAP), large tumor suppressor 1/2 kinase (LATS1/2), connective tissue growth factor, cysteine rich angiogenic inducer 61 and Merlin were assessed using western blotting and reverse transcription-quantitative PCR, respectively, to investigate the mechanism by which INHBA may affect the invasion of NSCLC. The present study revealed that INHBA was significantly upregulated in 238 clinical NSCLC samples compared with its expression levels in paired adjacent non-cancerous tissues, and in metastatic nodules compared with in primary tumors. Notably, high INHBA expression was statistically associated with clinicopathological features, including poor differentiation and advanced tumor stage. INHBA positivity was statistically related to decreased 5-year overall survival, for which INHBA was an independent prognostic factor. Furthermore, INHBA promoted NSCLC invasion in vitro. In NSCLC, INHBA expression was associated with the nuclear levels of YAP and INHBA overexpression enhanced the invasive abilities of NSCLC cells via inhibiting the Hippo pathway. Mechanistically, INHBA inhibited l LATS1/2 phosphorylation and induced YAP nuclear translocation by downregulating the protein expression levels of Merlin. In conclusion, INHBA may negatively regulate the Hippo pathway to act as a tumor promotor, and could represent a marker of prognosis in NSCLC.

Application of iPSCs derived pancreatic β-like cells using pancreatic bio-scaffold

This study aimed toengineer a pancreatic tissue. Intact rat pancreases were successfully decellularized, and were reseeded with human-induced pluripotent stem cells using different 2D and 3D culture growth factors. The differentiation process was assessed for the presence of a pancreas-like tissue. The histology and SEM analysis revealed cell attachment in all samples, except for the Exp4, and the Flow-cytometry provided 87% viability for the differentiated cells. In Exp1, PDX1 with the positive expression of 2.87±0.06 was dramatically higher than Exp2 with a 2.44±0.06 reaction. NGN3-reactions were 8±0.1 and 6.6±0.2 in Exp1 and Exp2 at P < 0.05, respectively. C-peptide with the expression of 7.5±0.7 in Exp3 was almost equal to that in Exp1 and Exp2. Glucagon (5.1±1) and PDX1 (3.2±0.82) in Exp3 indicated no significant difference. The significant upregulations of pancreatic endocrine markers (PDX1 and NGN3), and the cell-specific glucose transporter (GLUT2) were observed in the differentiated IPCs in the 3D culture of Exp2 after 21 days. The highest insulin and C-peptide concentrations were observed in Exp2. In Exp3, insulin secretion in response to high glucose and 10 mM arginine was 42.43 ±6.34 μU/ml. A decellularized pancreas in the presence of hiPSCs and growth factors could be efficiently used as a natural scaffold.

Emerging role of tumor microenvironment derived exosomes in therapeutic resistance and metastasis through epithelial-to-mesenchymal transition

The tumor microenvironment (TME) constitutes multiple cell types including cancerous and non-cancerous cells. The intercellular communication between these cells through TME derived exosomes may either enhance or suppress the tumorigenic processes. The tumor-derived exosomes could convert an anti-tumor environment into a pro-tumor environment by inducing the differentiation of stromal cells into tumor-associated cells. The exosomes from tumor-associated stromal cells reciprocally trigger epithelial-to-mesenchymal transition (EMT) in tumor cells, which impose therapeutic resistance and metastasis. It is well known that these exosomes contain the signals of EMT, but how these signals execute chemoresistance and metastasis in tumors remains elusive. Understanding the significance and molecular signatures of exosomes transmitting EMT signals would aid in developing appropriate methods of inhibiting them. In this review, we focus on molecular signatures of exosomes that shuttle between cancer cells and their stromal populations in TME to explicate their impact on therapeutic resistance and metastasis through EMT. Especially Wnt signaling is found to be involved in multiple ways of exosomal transport and hence we decipher the biomolecules of Wnt signaling trafficked through exosomes and their potential in serving as therapeutic targets.

Relevance of plasma bone marrow Activin-A and CXCL-12 concentration levels as a biomarker in acute myeloid leukemia

BACKGROUND

Acute myeloid leukemia changes the bone marrow (BM) niche to support leukemia cells by modulating the stromal microenvironment. The aim is to assess Activin-A as a biomarker in acute myeloid leukemia (AML).

METHODS

The level of Activin-A and CXCL-12 protein concentration levels in the plasma of bone marrow aspirate samples of eighty AML patients at diagnosis, after induction and at relapse were determined by ELISA.

RESULTS

We found that Activin-A concentration levels was significantly up regulated in AML cases at diagnosis, and down regulated at complete remission and rise again at relapse (P< 0.001). In contrast; the CXCL-12 gene expression was significantly down regulated in AML cases at diagnosis; relapse, and up regulated after complete remission (P< 0.001). Multivariate analysis showed that high Activin-A levels at diagnosis is significant predictor of induction of remission response OR 1.006 (CI: 1.002-1.010) (P= 0.003); AML relapse OR 1.002 (CI: 1.0-1.004) (P= 0.043) as well as patients' outcome OR 1.33 (CI: 1.004-1.062) (P= 0.024).

CONCLUSION

Activin-A level at diagnosis is a new simple easily assessed biomarker that could predict AML patient's response to therapy as well as patient's outcome.

Inhibitory effect of activin A on IL-9 production by mouse NK cells through Smad3 signaling

Interleukin-9 (IL-9) is a cytokine secreted by T-helper (Th)9 cells, and activin A can enhance Th9 cell differentiation. However, whether activin A affects IL-9 production by natural killer (NK) cells remains unclear. Herein, we found that not only Th cells, but also CD3-CD49b+NKp46+ NK cells of Balb/c mice produced IL-9. Although activin A promoted IL-9 expression in CD4+ Th cells, it inhibited IL-9 production by CD49b+NKp46+ NK cells in mice. Furthermore, the enzyme-linked immunosorbent assay (ELISA) results showed that mouse NK cells could secrete mature IL-9 protein, and activin A inhibited IL-9 release by NK cells. Additionally, activin A inhibited interferon (IFN)-γ production in splenic NK cells in mice, but promoted IL-2 production, and did not alter the production of IL-10. Western blotting results showed that levels of activin type IIA receptor (ActRIIA), Smad3 and phosphorylated-Smad3 (p-SMAD3) protein increased in activin A-treated splenic NK cells, compared with that in control NK cells. The inhibitory effects of activin A on IL-9 production by NK cells were attenuated in the presence of activin antagonist follistatin (FST) or Smad3 knockdown to NK cells. These data suggest that although activin A up-regulates IL-9 expression in Th cells, it inhibits IL-9 production in NK cells through Smad3 signaling.

Effect of Hesperidin against Induced Colon Cancer in Rats: Impact of Smad4 and Activin A Signaling Pathway

SCOPE

To evaluate the chemopreventive efficacy of hesperidin (Hsd) in 1,2-dimethylhydrazine (DMH)-induced colorectal cancer (CRC) and demonstrate its role in mothers against decapentaplegic homolog 4(Smad4) and activin A signaling pathways.

METHODS AND RESULTS

A CRC rat model was established by DMH exposure, and the animals were randomly divided into five groups: Control group, Hsd, DMH, DMH + Hsd, and DMH followed by Hsd. The resected colon was subjected to macroscopic, microscopic, molecular, histopathological, and immunohistochemical examination. Activin A, Smad4, malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), and superoxide dismutase (SOD) levels in tissues were also measured. The DMH group exhibited a significant increase in the gene and protein expression of activin A as well as MDA and NO levels in tissues. There was a significant reduction in the gene and protein expression of Smad4 as well as GSH and SOD levels in tissues. Administration of Hsd significantly upregulated Smad4 and activin A gene expressions in both the DMH + Hsd and DMH followed by Hsd groups. Moreover, Hsd improved the antioxidant status of the former two groups.

CONCLUSION

This study demonstrated the chemopreventive effect of Hsd against CRC by modulating Smad4 and activin A signaling in vivo. Further studies are needed to demonstrate its clinical value and explore its possible role in advanced malignancy.

Abnormal bone marrow microenvironment: the “harbor” of acute lymphoblastic leukemia cells

Bone marrow (BM) microenvironment regulates and supports the production of blood cells which are necessary to maintain homeostasis. In analogy to normal hematopoiesis, leukemogenesis is originated from leukemic stem cells (LSCs) which gives rise to more differentiated malignant cells. Leukemia cells occupy BM niches and reconstruct them to support leukemogenesis. The abnormal BM niches are the main sanctuary of LSCs where they can evade chemotherapy-induced death and acquire drug resistance. In this review, we focus on the protective effects of BM niche cells on acute lymphoblastic leukemia cells.

Radiotherapy: An immune response modifier for immuno-oncology

The ability of radiotherapy to enhance antigenicity and adjuvanticity of an irradiated tumor has stimulated the interest for its combination with immuno-oncology agents. However, radiotherapy often generates multiple layers of host responses which likely depends on the tumor biology, the immune cell infiltration and the induction of immunosuppressive signals post radiotherapy. Consequently, translation of preclinical findings to the clinic is more convoluted than anticipated which underscore the need to decipher molecular and cellular mechanisms elicited by radiotherapy. Here we review pro-inflammatory and immunosuppressive mechanisms triggered by radiotherapy that impact the outcome of antigen specific T cell killing and discuss how radiation-induced immunostimulatory mechanisms can be exploited to reactivate the host's immune system, especially in the context of immunotherapy.

Activin A backs-up TGF-ß to promote regulatory T cells

The mechanisms accountable for the infiltration of regulatory T cells into an irradiated tumor remain elusive. In our recent study, we demonstrate that activin A promotes regulatory T cells in tumors, and impairs anti-tumor immune responses induced by radiotherapy and TGF-β blockade. Dual blockade of activin A and TGF-β may be necessary to reduce regulatory T cells mediated immunosuppression driven by radiation therapy.

Botter S. Inhibition of the activin receptor signaling pathway: A novel intervention against osteosarcoma

Osteosarcoma is a cancer of pathological bone remodeling with high mortality and severe comorbidity. New therapies are urgently needed. Activin A, a member of the transforming growth factor β (TGFβ) superfamily, has been suggested to stimulate proliferation and invasion of osteosarcoma cells in vitro, thus representing a potential therapeutic target. In this study, inhibition of the activin receptor signaling pathway was explored as a therapy for osteosarcoma. In a murine intratibial osteosarcoma xenograft model, two types of inhibitors were tested: (a) a soluble activin type IIA decoy receptor (ActRIIA-mFc), or (b) a modified variant of follistatin (FSTΔHBS -hFc), either alone or in combination with a bisphosphonate. Both inhibitors reduced primary tumor development by nearly 50% compared to vehicle treatment. When ActRIIA-mFc was combined with bisphosphonate, the effect on tumor size became even more pronounced (78% reduction vs. vehicle). Moreover, FSTΔHBS -hFc increased body weight in the face of tumor progression (14% increase vs. vehicle), and ActRIIA-mFc reduced the number of lung metastases when combined with bisphosphonate. The present study demonstrates a novel approach to treating osteosarcoma and encourages further investigation of inhibition of the activin receptor signaling pathway as an intervention against the disease.

Metallothionein-1G suppresses pancreatic cancer cell stemness by limiting activin A secretion via NF-κB inhibition

Resistance to chemotherapy is a long-standing problem in the management of cancer, and cancer stem cells are regarded as the main source of this resistance. This study aimed to investigate metallothionein (MT)-1G involvement in the regulation of cancer stemness and provide a strategy to overcome chemoresistance in pancreatic ductal adenocarcinoma (PDAC). Methods: MT1G was identified as a critical factor related with gemcitabine resistance in PDAC cells by mRNA microarray. Its effects on PDAC stemness were evaluated through sphere formation and tumorigenicity. LC-MS/MS analysis of conditional medium revealed that activin A, a NF-κB target, was a major protein secreted from gemcitabine resistant PDAC cells. Both loss-of-function and gain-of-function approaches were used to validate that MT1G inhibited NF-κB-activin A pathway. Orthotopic pancreatic tumor model was employed to explore the effects on gemcitabine resistance with recombinant follistatin to block activin A. Results: Downregulation of MT1G due to hypermethylation of its promoter is related with pancreatic cancer stemness. Secretome analysis revealed that activin A, a NF-κB target, was highly secreted by drug resistant cells. It promotes pancreatic cancer stemness in Smad4-dependent or independent manners. Mechanistically, MT1G negatively regulates NF-κB signaling and promotes the degradation of NF-κB p65 subunit by enhancing the expression of E3 ligase TRAF7. Blockade of activin A signaling with follistatin could overcome gemcitabine resistance. Conclusions: MT1G suppresses PDAC stemness by limiting activin A secretion via NF-κB inhibition. The blockade of the activin A signaling with follistatin may provide a promising therapeutic strategy for overcoming gemcitabine resistance in PDAC.

Identifying Common Genes Related to Platelet and Immunity for Lung Adenocarcinoma Prognosis Prediction

Background

Although 1000s of immune-related and platelet receptor-related genes have been identified in lung adenocarcinoma, their role in prognosis prediction remains unclear.

Methods

We downloaded mRNA data from the Cancer Genome Atlas Dataset (TCGA), and GSE68465 or GSE14814 data sets from the Gene Expression Omnibus (GEO) database.

Results

The high-risk group’s overall survival (OS) time was lower than that of the low-risk group’s in TCGA (p = 1.15e-03). Additionally, the risk score was an independent prognostic survival factor for lung adenocarcinoma patients in TCGA (HR = 2.136, 95%CI = 1.553–2.937, p < 0.001). The model’s prognostic performance was verified with two independent GEO cohorts (GSE68465 and GSE14814). We also developed a nomogram and provided free webpage prediction tools.¹ The mechanism of the high-risk group in this risk score may be have been related to somatic mutations and copy number changes. In addition, this risk score can distinguish the prognosis of the other two cancers (ACC, p < 0.001 and KIRP, p < 0.001). Also, among the other seven cancers, the OS prognosis for high and low risk groups show wide variation (p < 0.05).

Conclusion

Our research demonstrates that CCNA2 and TGFB2 are potential diagnostic and prognostic biomarkers, as well as therapeutic targets in lung adenocarcinoma (LUAD). We also determined a novel and reliable prognostic score for lung adenocarcinoma prognosis. The online nomogram prediction tool that contains this risk score may also help clinical medical staff.

Activin A Promotes Regulatory T-cell-Mediated Immunosuppression in Irradiated Breast Cancer

Increased regulatory T cells (Treg) after radiotherapy have been reported, but the mechanisms of their induction remain incompletely understood. TGFβ is known to foster Treg differentiation within tumors and is activated following radiotherapy. Thus, we hypothesized that TGFβ blockade would result in decreased Tregs within the irradiated tumor microenvironment. We found increased Tregs in the tumors of mice treated with focal radiotherapy and TGFβ blockade. This increase was mediated by upregulation of another TGFβ family member, activin A. In vitro, activin A secretion was increased following irradiation of mouse and human breast cancer cells, and its expression was further enhanced upon TGFβ blockade. In vivo, dual blockade of activin A and TGFβ was required to decrease intratumoral Tregs in the context of radiotherapy. This resulted in an increase in CD8⁺ T-cell priming and was associated with a reduced tumor recurrence rate. Combination of immune checkpoint inhibitors with the dual blockade of activin A and TGFβ led to the development of tumor-specific memory responses in irradiated breast cancer. Supporting the translational value of activin A targeting to reduce Treg-mediated immunosuppression, retrospective analysis of a public dataset of patients with breast cancer revealed a positive correlation between activin A gene expression and Treg abundance. Overall, these results shed light on an immune escape mechanism driven by activin A and suggest that dual targeting of activin A and TGFβ may be required to optimally unleash radiation-induced antitumor immunity against breast cancer.

Heterogeneity of the bone marrow niche in patients with myeloproliferative neoplasms: ActivinA secretion by mesenchymal stromal cells correlates with the degree of marrow fibrosis

Mesenchymal stromal cells (MSCs) represent an essential component of the bone marrow (BM) niche and display disease-specific alterations in several myeloid malignancies. The aim of this work was to study possible MSC abnormalities in Philadelphia-negative myeloproliferative neoplasms (MPNs) in relationship to the degree of BM fibrosis. MSCs were isolated from BM of 6 healthy donors (HD) and of 23 MPN patients, classified in 3 groups according to the diagnosis and the grade of BM fibrosis: polycythemia vera and essential thrombocythemia (PV/ET), low fibrosis myelofibrosis (LF-MF), and high fibrosis MF (HF-MF). MSC cultures were established from 21 of 23 MPN patients. MPN-derived MSCs did not exhibit any functional impairment in their adipogenic/osteogenic/chondrogenic differentiation potential and displayed a phenotype similar to HD-derived MSCs but with a decreased expression of CD146. All MPN-MSC lines were negative for the patient-specific hematopoietic clone mutations (JAK2, MPL, CALR). MSCs derived from HF-MF patients displayed a reduced clonogenic potential and a lower growth kinetic compared to MSCs from HD, LF-MF, and PV/ET patients. mRNA levels of hematopoiesis regulatory molecules were unaffected in MSCs from HF-MF compared to HD. Finally, in vitro ActivinA secretion by MSCs was increased in HF-MF compared to LF-MF patients, in association with a lower hemoglobin value. Increased ActivinA immunolabeling on stromal cells and erythroid precursors was also observed in HF-MF BM biopsies. In conclusion, higher grade of BM fibrosis is associated with functional impairment of MSCs and the increased secretion of ActivinA may represent a suitable target for anemia treatment in MF patients.

Leveraging genetic data to investigate molecular targets and drug repurposing candidates for treating alcohol use disorder and hepatotoxicity

BACKGROUND

Novel treatments for alcohol use disorder (AUD) and alcohol-related liver disease (ALD) are greatly needed. Genetic information can improve drug discovery rates by facilitating the identification of novel biological targets and potential drugs for repurposing.

METHODS

The present study utilized a recently developed Bayesian approach, Integrative Risk Gene Selector (iRIGS), to identify additional risk genes for alcohol consumption using SNPs from the largest alcohol consumption GWAS to date (N = 941,280). iRIGS incorporates several genomic features and closeness of these genes in network space to compute a posterior probability for protein coding genes near each SNP. We subsequently used the Target Central Resource Database to search for drug-protein interactions for these newly identified genes and previously identified risk genes for alcohol consumption.

RESULTS

We identified several genes that are novel contributions to the previously published alcohol consumption GWAS. Namely, ACVR2A, which is critical for liver function and linked to anxiety and cocaine self-administration, and PRKCE, which has been linked to alcohol self-administration. Notably, only a minority of the SNPs (18.4 %) were linked to genes with confidence (>0.75), underscoring the need to apply multiple methods to assign function to loci. Finally, some previously identified risk genes for alcohol consumption code for proteins that are implicated in liver function and are targeted by drugs, some of which are candidates for managing hepatotoxicity.

CONCLUSIONS

This study demonstrates the value of incorporating regulatory information and drug-protein interaction data to highlight additional molecular targets and drug repurposing candidates for treating AUD and ALD.

Activin A: an emerging target for improving cancer treatment?

INTRODUCTION

Activin A is involved in the regulation of a surprisingly broad number of processes that are relevant for cancer development and treatment; it is implicated in cell autonomous functions and multiple regulatory functions in the tumor microenvironment.

AREAS COVERED

This article summarizes the current knowledge about activin A in cell growth and death, migration and metastasis, angiogenesis, stemness and drug resistance, regulation of antitumor immunity, and cancer cachexia. We explore the role of activin A as a biomarker and discuss strategies for using it as target for cancer therapy. Literature retrieved from Medline until 25 June 2020 was considered.

EXPERT OPINION

While many functions of activin A were investigated in preclinical models, there is currently limited experience from clinical trials. Activin A has growth- and migration-promoting effects, contributes to immune evasion and cachexia and is associated with shorter survival in several cancer types. Targeting activin A could offer the chance to simultaneously limit tumor growth and spreading, improve drug response, boost antitumor immune responses and improve cancer-associated or treatment-associated cachexia, bone loss, and anemia. Nevertheless, defining which patients have the highest likelihood of benefiting from these effects is challenging and will require further work.

BMP4-mediated autophagy is involved in the metastasis of hepatocellular carcinoma via JNK/Beclin1 signaling

The role of autophagy in tumor development is complicated. More signaling mechanisms of bone morphogenetic protein 4 (BMP4) involving in hepatocellular carcinoma (HCC) are needed to be clarified. The present study aimed to identify whether BMP4 contributes to the regulation of autophagy in the progression of HCC. We found that increased BMP4 expression was significantly correlated with TNM stage and metastasis. BMP4 treatment promoted HCC cells invasion and induced autophagy. Blocking autophagy by 3-MA or silenced Beclin1 attenuated BMP4-induced autophagy and cell invasion. Further study revealed that JNK/Beclin1 pathway participated in the process of autophagy and JNK inhibitor SP600125 could attenuate autophagy and reduce the invasive ability of HCC cells induced by BMP4. In a word, BMP4-induced autophagy facilitates invasion of HCC by JNK/Beclin1 signaling pathway.

Activin A triggers angiogenesis via regulation of VEGFA and its overexpression is associated with poor prognosis of oral squamous cell carcinoma

Poor prognosis associated with the dysregulated expression of activin A in a number of malignancies has been related to with numerous aspects of tumorigenesis, including angiogenesis. The present study investigated the prognostic significance of activin A immunoexpression in blood vessels and cancer cells in a number of oral squamous cell carcinoma (OSCC) cases and applied in vitro strategies to determine the impact of activin A on angiogenesis. In a cohort of 95 patients with OSCC, immunoexpression of activin A in both blood vessels and tumor cells was quantified and the association with clinicopathological parameters and survival was analyzed. Effects of activin A on the tube formation, proliferation and migration of human umbilical vein endothelial cells (HUVECs) were evaluated in gain‑of‑function (treatment with recombinant activin A) or loss‑of‑function [treatment with activin A‑antagonist follistatin or by stable transfection with short hairpin RNA (shRNA) targeting activin A] conditions. Conditioned medium from an OSCC cell line with shRNA‑mediated depletion of activin A was also tested. The profile of pro‑ and anti‑angiogenic factors regulated by activin A was assessed with a human angiogenesis quantitative PCR (qPCR) array. Vascular endothelial growth factor A (VEGFA) and its major isoforms were evaluated by reverse transcription‑qPCR and ELISA. Activin A expression in blood vessels demonstrated an independent prognostic value in the multivariate analysis with a hazard ratio of 2.47 [95% confidence interval (CI), 1.30‑4.71; P=0.006) for disease‑specific survival and 2.09 (95% CI, 1.07‑4.08l: P=0.03) for disease‑free survival. Activin A significantly increased tubular formation of HUVECs concomitantly with an increase in proliferation. This effect was validated by reduced proliferation and tubular formation of HUVECs following inhibition of activin A by follistatin or shRNA, as well as by treatment of HUVECs with conditioned medium from activin A‑depleted OSCC cells. Activin A‑knockdown increased the migration of HUVECs. In addition, activin A stimulated the phosphorylation of SMAD2/3 and the expression and production of total VEGFA, significantly enhancing the expression of its pro‑angiogenic isoform 121. The present findings suggest that activin A is a predictor of the prognosis of patients with OSCC, and provide evidence that activin A, in an autocrine and paracrine manner, may contribute to OSCC angiogenesis through differential expression of the isoform 121 of VEGFA.

Fallopian tube initiation of high grade serous ovarian cancer and ovarian metastasis: Mechanisms and therapeutic implications

Ovarian cancer is the most lethal gynecologic malignancy and the fifth leading cause of cancer-related death in women. Although outcomes have improved in recent years, there remains an unmet clinical need to understand the early pathogenesis of ovarian cancer in order to identify new diagnostic approaches and agents of chemoprevention and chemotherapy. While high grade serous ovarian cancer (HGSOC), the most abundant histotype, was initially thought to arise from the ovarian surface epithelium, there is an increasing body of evidence suggesting that HGSOC originates in the fallopian tube. With this new understanding of cell of origin, understanding of disease development requires analysis with a novel perspective. Currently, factors that drive the initiation and migration of dysplastic tubal epithelial cells from the fallopian tube to the ovary are not yet fully defined. These factors include common mutations to fallopian tube epithelial cells, as well as factors originating from both the fallopian tube and ovary which are capable of inducing transformation and dissemination in said cells. Here, we review these changes, their causative agents, and various potential means of intervention.

Increased stiffness of the tumor microenvironment in colon cancer stimulates cancer associated fibroblast-mediated prometastatic activin A signaling

Colorectal cancer (CRC) is the second deadliest cancer in the US due to its propensity to metastasize. Stromal cells and especially cancer-associated fibroblasts (CAF) play a critical biophysical role in cancer progression, but the precise pro-metastatic mechanisms are not clear. Activin A, a TGF-β family member, is a strong pro-metastatic cytokine in the context of CRC. Here, we assessed the link between biophysical forces and pro-metastatic signaling by testing the hypothesis that CAF-generated mechanical forces lead to activin A release and associated downstream effects. Consistent with our hypothesis, we first determined that stromal activin A secretion increased with increasing substrate stiffness. Then we found that stromally-secreted activin A induced ligand-dependent CRC epithelial cell migration and epithelial to mesenchymal transition (EMT). In addition, serum activin A levels are significantly increased in metastatic (stage IV) CRC patients (1.558 ng/ml versus 0.4179 ng/ml, p < 0.05). We propose that increased tumor microenvironment stiffness leads to stromal cell-mediated TGF-β family signaling relying on the induction and utilization of activin A signaling.

TGF-β and microRNA Interplay in Genitourinary Cancers

Genitourinary cancers (GCs) include a large group of different types of tumors localizing to the kidney, bladder, prostate, testis, and penis. Despite highly divergent molecular patterns, most GCs share commonly disturbed signaling pathways that involve the activity of TGF-β (transforming growth factor beta). TGF-β is a pleiotropic cytokine that regulates key cancer-related molecular and cellular processes, including proliferation, migration, invasion, apoptosis, and chemoresistance. The understanding of the mechanisms of TGF-β actions in cancer is hindered by the "TGF-β paradox" in which early stages of cancerogenic process are suppressed by TGF-β while advanced stages are stimulated by its activity. A growing body of evidence suggests that these paradoxical TGF-β actions could result from the interplay with microRNAs: Short, non-coding RNAs that regulate gene expression by binding to target transcripts and inducing mRNA degradation or inhibition of translation. Here, we discuss the current knowledge of TGF-β signaling in GCs. Importantly, TGF-β signaling and microRNA-mediated regulation of gene expression often act in complicated feedback circuits that involve other crucial regulators of cancer progression (e.g., androgen receptor). Furthermore, recently published in vitro and in vivo studies clearly indicate that the interplay between microRNAs and the TGF-β signaling pathway offers new potential treatment options for GC patients.

Follistatin impacts Tumor Angiogenesis and Outcome in Thymic Epithelial Tumors

Tumor angiogenesis is a key factor in the progression of thymic epithelial tumors (TETs). Activin A, a member of the TGFβ family, and its antagonist Follistatin are involved in several human malignancies and angiogenesis. We investigated Activin A and Follistatin in serum and tumor tissue of patients with TETs in relation to microvessel density (MVD), WHO histology classification, tumor stage and outcome. Membranous Activin A expression was detected in all tumor tissues of TETs, while Follistatin staining was found in tumor nuclei and cytoplasm. Patients with TETs presented with significantly higher Activin A and Follistatin serum concentrations compared to healthy volunteers, respectively. Follistatin serum concentrations correlated significantly with tumor stage and decreased to physiologic values after complete tumor resection. Follistatin serum concentrations correlated further with MVD and were associated with significantly worse freedom from recurrence (FFR). Low numbers of immature tumor vessels represented even an independent worse prognostic factor for FFR at multivariable analysis. To conclude, the Activin A - Follistatin axis is involved in the pathogenesis of TETs. Further study of Follistatin and Activin A in TETs is warranted as the molecules may serve as targets to inhibit tumor angiogenesis and tumor progression.