Cancer cell-derived long pentraxin 3 (PTX3) promotes melanoma migration through a toll-like receptor 4 (TLR4)/NF-κB signaling pathway

Obesity-associated metabolic inflammation promotes triple-negative breast cancer progression through the interleukin-6/STAT3/pentraxin 3/matrix metalloproteinase 7 axis

BACKGROUND

This study aimed to investigate the regulatory mechanism of the adipose factor interleukin (IL)-6 in promoting pentraxin 3 (PTX3) expression in triple-negative breast cancer (TNBC).

METHODS

We established an in vitro coculture model of mature adipocytes and TNBC cells using a Transwell system. Cell scratch, Transwell migration, and matrix invasion assays were used to evaluate the migration and invasion abilities of TNBC cells cocultured with adipocytes. Next, we used lentivirus-mediated functional depletion experiments to study PTX3's role in the adipocyte-dependent migration of TNBC cells.

RESULTS

After coculturing TNBC cells with adipocytes, PTX3 expression was upregulated, which accompanied enhanced cell migration and invasion. Using GEO data and RNA-seq analysis, we identified PTX3 as a key target gene influenced by the adipose TNBC microenvironment. IL-6 upregulation in the conditioned medium of mature adipocytes and in the serum of high-fat diet mice was associated with this effect, and the recombinant protein IL-6 significantly promoted the migration and invasion of TNBC cells along with the phosphorylation of intracellular STAT3 and the upregulation of PTX3. PTX3 knockdown inhibited TNBC cell migration and eliminated the enhanced migration caused by coculturing with adipocytes. Furthermore, in vivo experiments confirmed that the PTX3 knockdown reduced obesity-induced lung metastasis. Subsequent experiments with cytokines and drug inhibitors confirmed that adipocyte-derived IL-6 promoted PTX3 expression by activating the STAT3 signaling pathway. Additionally, bioinformatic analysis indicated that PTX3 promotes TNBC metastasis by regulating the matrix metalloproteinase (MMP) family.

CONCLUSION

Our study elucidated Obesity-related metabolic inflammation promotes the progression via the IL-6/STAT3/PTX3/MMP7 axis.

Neutrophil-secreted S100A8/A9 participates in fatty liver injury and fibrosis by promoting myofibroblast migration

Fatty liver, which is induced by abnormal lipid metabolism, is one of the most common causes of chronic liver disease globally and causes liver fibrosis. During this process, bone marrow-derived mesenchymal stromal cells (BMSCs) and hepatic stellate cells (HSCs) migrate toward the injured liver and participate in fibrogenesis by transdifferentiating into myofibroblasts. S100A8/A9 is a powerful inducer of cell migration and is involved in liver injury. But there are few reports about the effects of S100A8/A9 on BMSC/HSC migration. In the current study, we found that S100A8/A9 expression was increased during fatty liver injury/fibrogenesis. Moreover, S100A8/A9 expression had a positive correlation with fibrosis marker gene expressions in the injured liver. S100A8/A9 was mainly produced by neutrophils in the fibrotic liver. In vitro, neutrophil-secreted S100A8/A9 promoted BMSC/HSC migration via remodeling of microfilaments. Using specific siRNA and inhibitor, we proved that S100A8/A9-induced BMSC/HSC migration is dependent on TLR4/Rho GTPases signaling. Moreover, S100A8/A9 knock-down alleviated liver injury and fibrogenesis in vivo, while injection of S100A9 neutralizing antibody performed similar roles. We proved that S100A8/A9 was involved in liver injury and fibrogenesis via inducing BMSC/HSC migration. Our research reveals a new mechanism underlying BMSC/HSC migration in liver fibrosis and suggests S100A8/A9 as a potential therapeutic target of liver fibrosis. KEY MESSAGES: S100A8/A9 is secreted by neutrophils and increased in fatty liver injury. Neutrophil-secreted S100A8/A9 is a mediator of BMSC/HSC migration in vitro. S100A8/A9-induced BMSC/HSC migration is dependent on TLR4/Rho GTPases signaling. S100A8/A9 blockade alleviates liver injury and fibrogenesis in vivo.

Pentraxin 3: A Main Driver of Inflammation and Immune System Dysfunction in the Tumor Microenvironment of Glioblastoma

Brain tumors are a heterogeneous group of brain neoplasms that are highly prevalent in individuals of all ages worldwide. Within this pathological framework, the most prevalent and aggressive type of primary brain tumor is glioblastoma (GB), a subtype of glioma that falls within the IV-grade astrocytoma group. The death rate for patients with GB remains high, occurring within a few months after diagnosis, even with the gold-standard therapies now available, such as surgery, radiation, or a pharmaceutical approach with Temozolomide. For this reason, it is crucial to continue looking for cutting-edge therapeutic options to raise patients' survival chances. Pentraxin 3 (PTX3) is a multifunctional protein that has a variety of regulatory roles in inflammatory processes related to extracellular matrix (ECM). An increase in PTX3 blood levels is considered a trustworthy factor associated with the beginning of inflammation. Moreover, scientific evidence suggested that PTX3 is a sensitive and earlier inflammation-related marker compared to the short pentraxin C-reactive protein (CRP). In several tumoral subtypes, via regulating complement-dependent and macrophage-associated tumor-promoting inflammation, it has been demonstrated that PTX3 may function as a promoter of cancer metastasis, invasion, and stemness. Our review aims to deeply evaluate the function of PTX3 in the pathological context of GB, considering its pivotal biological activities and its possible role as a molecular target for future therapies.

PTX3 activates POSTN and promotes the progression of glioblastoma via the MAPK/ERK signalling axis

BACKGROUND

Intrinsic brain tumours such as glioblastoma (GBM) are believed to develop from neuroglial stem or progenitor cells. GBM accounts for approximately half of gliomas. GBM has a poor prognosis and a low 5-year survival rate. Pentraxin 3 (PTX3) is overexpressed in GBM, but the potential mechanism is unclear.

METHODS

Glioblastoma data from the TCGA and CGGA databases were used to analyse PTX3 expression. Subsequently, in vivo and in vitro experiments were conducted to verify the effect of PTX3 silencing in glioma cells on EMT like process and GSC maintenance. The JASPAR database was used to predict the downstream genes of PTX3. POSTN is a novel target gene of PTX3 in gliomas, and this finding was validated using a luciferase reporter gene assay. Western blotting and KEGG enrichment analysis were used to predict the downstream pathway of POSTN, and it was found that the MAPK/ERK pathway might be related to the function of POSTN.

RESULTS

GBM tissues have higher levels of PTX3 expression than normal brain tissues (NBTs). In functional tests, PTX3 promoted the EMT like process of GBM cells while maintaining the stem cell characteristics of GBM stem cells and enhancing their self-renewal. Moreover, we performed a dual luciferase reporter experiment to confirm that PTX3 binds to the POSTN promoter region. In addition, the expression of key proteins in the MAPK/ERK signalling pathway was increased after PTX3 overexpression.

CONCLUSION

POSTN is a direct target of PTX3 that promotes GBM growth via the MAPK/ERK signalling pathway.

Inactivation of pentraxin 3 suppresses M2-like macrophage activity and immunosuppression in colon cancer

BACKGROUND

The tumor microenvironment is characterized by inflammation-like and immunosuppression situations. Although cancer-associated fibroblasts (CAFs) are among the major stromal cell types in various solid cancers, including colon cancer, the interactions between CAFs and immune cells remains largely uncharacterized. Pentraxin 3 (PTX3) is responsive to proinflammatory cytokines and modulates immunity and tissue remodeling, but its involvement in tumor progression appears to be context-dependent and is unclear.

METHODS

Open-access databases were utilized to examine the association of PTX3 expression and the fibroblast signature in colon cancer. Loss-of-function assays, including studies in tamoxifen-induced Ptx3 knockout mice and treatment with an anti-PTX3 neutralizing antibody (WHC-001), were conducted to assess the involvement of PTX3 in colon cancer progression as well as its immunosuppressive effect. Finally, bioinformatic analyses and in vitro assays were performed to reveal the downstream effectors and decipher the involvement of the CREB1/CEBPB axis in response to PTX3 and PTX3-induced promotion of M2 macrophage polarization.

RESULTS

Clinically, higher PTX3 expression was positively correlated with fibroblasts and inflammatory response signatures and associated with a poor survival outcome in colon cancer patients. Blockade of PTX3 significantly reduced stromal cell-mediated tumor development. The decrease of the M2 macrophage population and an increase of the cytotoxic CD8+ T-cell population were observed following PTX3 inactivation in allografted colon tumors. We further revealed that activation of cyclic AMP-responsive element-binding protein 1 (CREB1) mediated the PTX3-induced promotion of M2 macrophage polarization.

CONCLUSIONS

PTX3 contributes to stromal cell-mediated protumor immunity by increasing M2-like macrophage polarization, and inhibition of PTX3 with WHC-001 is a potential therapeutic strategy for colon cancer.

RPLP2 activates TLR4 in an autocrine manner and promotes HIF-1α-induced metabolic reprogramming in hepatocellular carcinoma

Metabolic reprogramming is a major feature of cancer, and aerobic glycolysis is one of the most widely studied metabolic reprogramming processes. Acidic ribosome protein P2 (RPLP2) is associated with both tumorigenesis and endoplasmic reticulum stress. However, limited knowledge exists regarding the role of RPLP2 in hepatocellular carcinoma (HCC) progression. In the present study, we observed a significant upregulation of RPLP2 in HCC tissues. Moreover, RPLP2 expression is closely correlated with patient prognosis and survival. The subsequent experimental validation demonstrated that RPLP2 exerted a regulatory effect on the expression of glycolytic enzymes and lactate production, thereby facilitating HCC cell proliferation. Mechanistically, the PI3K/AKT signalling pathway was found to play an important role in the regulation of hypoxia-inducible factor-1α (HIF-1α)-mediated aerobic glycolysis and cell growth. RPLP2 activates TLR4 on the surface of HCC cells and the downstream PI3K/AKT pathway through autocrine signalling. This activation then facilitates the entry of HIF-1α into the nucleus, enabling it to fulfil its transcriptional function. In conclusion, our findings suggested that RPLP2 induces a metabolic shift towards aerobic glycolysis and facilitates the progression of HCC through TLR4-dependent activation of the PI3K/AKT/HIF-1α pathway. Our study revealed the novel mechanism by which the ribosomal protein RPLP2 regulates glycolysis to promote HCC progression. These findings may offer a potential therapeutic target for HCC treatment.

Role of long pentraxin PTX3 in cancer

Cancer has become a leading cause of death and disease burden worldwide, closely related to rapid socioeconomic development. However, the fundamental reason is the lack of comprehensive understanding of the mechanism of cancer, accurate identification of preclinical cancer, and effective treatment of the disease. Therefore, it is particularly urgent to study specific mechanisms of cancer and develop effective prediction and treatment methods. Long Pentraxin PTX3 is a soluble pattern recognition molecule produced by various cells in inflammatory sites, which plays a role as a promoter or suppressor of cancer in multiple tumors through participating in innate immune response, neovascularization, energy metabolism, invasion, and metastasis mechanisms. Based on this, this article mainly reviews the role of PTX3 in various cancers.

Knockdown of LRRK2 inhibits the progression of lung cancer by regulating TLR4/NF-κB pathways and NLRP3 inflammasome

Leucine-rich repeat kinase 2 (LRRK2) plays an important role in a variety of inflammatory diseases, as well as peripheral and central immune responses. At present, there are few reports about the role of LRRK2 in lung cancer, and need to be further explored. The main purpose of this study is to explore the role and mechanism of LRRK2 in lung cancer. The results revealed that the expression of LRRK2 was increased in the tissues of lung cancer patient and lung cancer cells. Further studies found that interference with LRRK2 expression significantly induced the apoptosis, and promoted the expression of caspase-3, caspase-9, and Bax. More importantly, si-LRRK2 inhibited the expression of VEGF and P-gp, indicating inhibition of cell proliferation and drug resistance. What's more, LRRK2 regulated TLR4/NF-κB signaling pathways and NLRP3 inflammasome, and TLR4/NF-κB pathways was involved in the molecular mechanism of LRRK2 on lung cancer cells. In conclusion, this study suggested that the mechanism of si-LRRK2 inhibiting the progression of lung cancer is to regulate the TLR4/NF-κB signaling pathways and NLRP3 inflammasome.

The PTX3/TLR4 autocrine loop as a novel therapeutic target in triple negative breast cancer

BACKGROUND

The pattern recognition receptor long pentraxin-3 (PTX3) plays conflicting roles in cancer by acting as an oncosuppressor or as a pro-tumor mediator depending on tumor context. Triple negative breast cancer (TNBC) represents the most aggressive histotype of breast cancer, characterized by the lack of efficacious therapeutic targets/approaches and poor prognosis. Thus, the characterization of new molecular pathways and/or alternative druggable targets is of great interest in TNBC.

METHODS

The expression of PTX3 in BC tumor samples and in BC cell lines has been analyzed using the Gene Expression-Based Outcome for Breast Cancer Online (GOBO), qPCR, Western blot and ELISA assay. The contribution of tumor and stromal cells to PTX3 production in TNBC was assessed by analyzing single cell RNA sequencing data and RNAscope performed on TNBC tumor samples. In order to investigate the effects of PTX3 in TNBC, different cell lines were engineered to knock-down (MDA-MB-231 and BT549 cells) or overexpress (MDA-MB-468 and E0771 cells) PTX3. Finally, using these engineered cells, in vitro (including gene expression profiling and gene set enrichment analyses) and in vivo (orthotopic tumor models in immune-compromised and immune competent mice) analyses were performed to assess the role and the molecular mechanism(s) exerted by PTX3 in TNBC.

RESULTS

In silico and experimental data indicate that PTX3 is mainly produced by tumor cells in TNBC and that its expression levels correlate with tumor stage. Accordingly, gene expression and in vitro results demonstrate that PTX3 overexpression confers a high aggressive/proliferative phenotype and fosters stem-like features in TNBC cells. Also, PTX3 expression induces a more tumorigenic potential when TNBC cells are grafted orthotopically in vivo. Conversely, PTX3 downregulation results in a less aggressive behavior of TNBC cells. Mechanistically, our data reveal that PTX3 drives the activation of the pro-tumorigenic Toll-like receptor 4 (TLR4) signaling pathway in TNBC, demonstrating for the first time that the PTX3/TLR4 autocrine stimulation loop contributes to TNBC aggressiveness and that TLR4 inhibition significantly impacts the growth of PTX3-producing TNBC cells.

CONCLUSION

Altogether, these data shed light on the role of tumor-produced PTX3 in TNBC and uncover the importance of the PTX3/TLR4 axis for therapeutic and prognostic exploitation in TNBC.

Serum Pentraxin 3 as Promising Biomarker for the Long-Lasting Inflammatory Response of COVID-19

Currently, biological markers for COVID-19 disease severity still constitute the main goal of enhancing an efficient treatment to reduce critical consequences such as an abnormal systemic inflammatory response. In this regard, the latest research has shown that Pentraxin 3 (PTX3), a highly conserved innate immunity protein, may serve as a valuable biochemical marker. Based on this evidence, we conducted a case-control study to compare the PTX3 serum levels and several immune-inflammatory mediators of 80 healthcare workers who were subdivided into subjects who were previously infected with SARS-CoV-2 (n = 40) and individuals who were never infected (n = 40). Using a commercially available Enzyme-Linked Immunosorbent Assay (ELISA), PTX3 and various immune-inflammatory protein levels were assessed in serum samples, while also considering possible variables (e.g., gender-related differences). We have shown elevated levels of PTX3 and other inflammatory proteins in previously infected COVID-19-positive subjects (p < 0.001). Moreover, the obtained data also indicate a degree of severity influenced by gender, as shown by the subgroup analysis, in which PTX3 expression was more pronounced in previously COVID-19-positive males (p < 0.001) than in females (p < 0.05) compared to the respective controls. In addition, our data further validate, through a direct comparison of previously COVID-19-positive subjects, greater pro-inflammatory levels in males than in females. Overall, our results may support the validity of PTX3 as a systemic biomarker in prolonged systemic inflammatory responses in the context of COVID-19. Thus, PTX3 modulation could constitute an effective therapeutic strategy for improving the recovery from COVID-19 and its systemic long-term consequences.

MTAP-ANRIL gene fusion promotes melanoma epithelial-mesenchymal transition-like process by activating the JNK and p38 signaling pathways

Gene fusions caused by cytogenetic aberrations play important roles in the initiation and progression of cancers. The recurrent MTAP-ANRIL fusion gene was reported to have a frequency of greater than 7% in melanoma in our previous study. However, its functions remain unclear. Truncated MTAP proteins resulting from point mutations in the last three exons of MTAP can physically interact with the wild-type MTAP protein, a tumor suppressor in several human cancers. Similarly, MTAP-ANRIL, which is translated into a truncated MTAP protein, would influence wild-type MTAP to act as an oncogene. Here, we found that MTAP-ANRIL gene fusion downregulated the expression of wild-type MTAP and promoted epithelial-mesenchymal transition-like process through the activation of JNK and p38 MAPKs in vitro and in vivo. Our results suggest that MTAP-ANRIL is a potential molecular prognostic biomarker and therapeutic target for melanoma.

A new immune checkpoint-associated nine-gene signature for prognostic prediction of glioblastoma

Glioblastoma (GBM) is a highly malignant neurological tumor that has a poor prognosis. While pyroptosis affects cancer cell proliferation, invasion and migration, function of pyroptosis-related genes (PRGs) in GBM as well as the prognostic significance of PRGs remain obscure. By analyzing the mechanisms involved in the association between pyroptosis and GBM, our study hopes to provide new insights into the treatment of GBM. Here, 32 out of 52 PRGs were identified as the differentially expressed genes between GBM tumor versus normal tissues. And all GBM cases were assigned to 2 groups according to the expression of the differentially expressed genes using comprehensive bioinformatics analysis. The least absolute shrinkage and selection operator analysis led to the construction of a 9-gene signature, and the cancer genome atlas cohort of GBM patients were categorized into high risk and low risk subgroups. A significant increase in the survival possibility was found in low risk patients in comparison with the high risk ones. Consistently, low risk patients of a gene expression omnibus cohort displayed a markedly longer overall survival than the high risk counterparts. The risk score calculated using the gene signature was found to be an independent predictor of survival of GBM cases. Besides, we observed significant differences in the expression levels of immune checkpoints between the high risk versus low risk GBM cases, providing instructive suggestions for immunotherapy of GBM. Overall, the present study developed a new multigene signature for prognostic prediction of GBM.

The mechanical phenotypic plasticity of melanoma cell: an emerging driver of therapy cross-resistance

Advanced cutaneous melanoma is the deadliest form of skin cancer and one of the most aggressive human cancers. Targeted therapies (TT) against BRAF mutated melanoma and immune checkpoints blockade therapies (ICB) have been a breakthrough in the treatment of metastatic melanoma. However, therapy-driven resistance remains a major hurdle in the clinical management of the metastatic disease. Besides shaping the tumor microenvironment, current treatments impact transition states to promote melanoma cell phenotypic plasticity and intratumor heterogeneity, which compromise treatment efficacy and clinical outcomes. In this context, mesenchymal-like dedifferentiated melanoma cells exhibit a remarkable ability to autonomously assemble their own extracellular matrix (ECM) and to biomechanically adapt in response to therapeutic insults, thereby fueling tumor relapse. Here, we review recent studies that highlight mechanical phenotypic plasticity of melanoma cells as a hallmark of adaptive and non-genetic resistance to treatment and emerging driver in cross-resistance to TT and ICB. We also discuss how targeting BRAF-mutant dedifferentiated cells and ECM-based mechanotransduction pathways may overcome melanoma cross-resistance.

SPON2 promotes the bone metastasis of lung adenocarcinoma via activation of the NF-κB signaling pathway

Bone metastasis severely affects the life span and quality of life of survivors of lung adenocarcinoma (ADC). There is a pressing need to identify viable biomarkers for this incurable, fatal disease. Spondin-2 (SPON2) has been reported to be involved in metastasis and cancer progression, but its role in bone metastasis in patients with lung ADC has rarely been studied. Here, we showed that the upregulation of SPON2 increased the migration, invasion, and epithelial-to-mesenchymal transition of ADC cells in vitro, whereas silencing SPON2 repressed these processes. Consistently, silencing SPON2 significantly reduced the bone metastasis of ADC cells in vivo. Mechanistically, SPON2 activated the nuclear factor-κB (NF-κB) signaling pathway and increased the expression levels of MMP2 and MMP9. Blocking NF-κB using an inhibitor attenuated the SPON2-induced migration and invasion of ADC cells. In addition, we found that SPON2 expression levels were increased in metastatic bone tissues compared to primary ADC tissues. The upregulation of SPON2 was positively correlated with MMP2 and MMP9 expression levels in metastatic bone tissues. In conclusion, these results illustrate that SPON2 plays a key role in ADC by activating the NF-κB pathway to promote bone metastasis, which suggests that it may be a target for future drug development.

Identifying the Transcriptional Drivers of Metastasis Embedded within Localized Melanoma

In melanoma, predicting which tumors will ultimately metastasize guides treatment decisions. Transcriptional signatures of primary tumors have been utilized to predict metastasis, but which among these are driver or passenger events remains unclear. We used data from the adjuvant AVAST-M trial to identify a predictive gene signature in localized tumors that ultimately metastasized. Using a zebrafish model of primary melanoma, we interrogated the top genes from the AVAST-M signature in vivo. This identified GRAMD1B, a cholesterol transfer protein, as a bona fide metastasis suppressor, with a majority of knockout animals rapidly developing metastasis. Mechanistically, excess free cholesterol or its metabolite 27-hydroxycholesterol promotes invasiveness via activation of an AP-1 program, which is associated with increased metastasis in humans. Our data demonstrate that the transcriptional seeds of metastasis are embedded within localized tumors, suggesting that early targeting of these programs can be used to prevent metastatic relapse.

SIGNIFICANCE

We analyzed human melanoma transcriptomics data to identify a gene signature predictive of metastasis. To rapidly test clinical signatures, we built a genetic metastasis platform in adult zebrafish and identified GRAMD1B as a suppressor of melanoma metastasis. GRAMD1B-associated cholesterol overload activates an AP-1 program to promote melanoma invasion. This article is highlighted in the In This Issue feature, p. 1.

PARP Inhibitor Inhibits the Vasculogenic Mimicry through a NF-κB-PTX3 Axis Signaling in Breast Cancer Cells

Poly (ADP-ribose) polymerase inhibitors (PARPi) are targeted therapies that inhibit PARP proteins which are involved in a variety of cell functions. PARPi may act as modulators of angiogenesis; however, the relationship between PARPi and the vasculogenic mimicry (VM) in breast cancer remains unclear. To determine whether PARPi regulate the vascular channel formation, we assessed whether the treatment with olaparib, talazoparib and veliparib inhibits the vascular channel formation by breast cancer cell lines. Here, we found that PARPi act as potent inhibitors of the VM formation in triple negative breast cancer cells, independently of the BRCA status. Mechanistically, we find that PARPi trigger and inhibit the NF-κB signaling, leading to the inhibition of the VM. We further show that PARPi decrease the expression of the angiogenic factor PTX3. Moreover, PTX3 rescued the PARPi-inhibited VM inhibition. In conclusion, our results indicate that PARPi, by targeting the VM, may provide a new therapeutic approach for triple negative breast cancer.

TLR4 Blockade Using Docosahexaenoic Acid Restores Vulnerability of Drug-Tolerant Tumor Cells and Prevents Breast Cancer Metastasis and Postsurgical Relapse

Nonmutational mechanisms were recently discovered leading to reversible drug tolerance. Despite the rapid elimination of a majority of tumor cells, a small subpopulation of "'drug-tolerant"' cells remain viable with lethal drug exposure, which may further lead to resistance or tumor relapse. Several signaling pathways are involved in the local or systemic inflammatory responses contributing to drug-induced phenotypic switch. Here, we report that Toll-like receptor 4 (TLR4)-interacting lipid docosahexaenoic acid (DHA) restores the cytotoxic effect of doxorubicin (DOX) in the lipopolysaccharide-treated breast tumor cell line 4T1, preventing the phenotypic switch to drug-tolerant cells, which significantly reduces primary tumor growth and lung metastasis in both 4T1 orthotopic and experimental metastasis models. Importantly, DHA in combination with DOX delays and inhibits tumor recurrence following surgical removal of the primary tumor. Furthermore, the coencapsulation of DHA and DOX in a nanoemulsion significantly prolongs the survival of mice in the postsurgical 4T1 tumor relapse model with significantly reduced systemic toxicity. The synergistic antitumor, antimetastasis, and antirecurrence effects of DHA + DOX combination are likely mediated by attenuating TLR4 activation, thus sensitizing tumor cells to standard chemotherapy.

A pyroptosis-associated signature plays a role in prognosis prediction in clear cell renal cell carcinoma

Background

Approximately 90% of renal malignancies are RCCs (renal cell carcinomas), and the primary subtype in histology is ccRCC (clear cell RCC). In recent years, pyroptosis has been considered a kind of inflammation-related programmed cell death that participates in the invasion, metastasis, and proliferation of tumour cells, thereby influencing tumour prognosis. Nonetheless, the expression level of pyroptosis-associated genes in RCCs and their relationship with prognosis remain obscure.

Results

In our research, 44 regulators of pyroptosis that were differentially expressed between normal kidney and ccRCC tissues were identified. ccRCC cases were categorized into 2 subgroups according to prognostic-related DEGs (differentially expressed genes), and there was a significant difference in OS (overall survival) between them. The prognostic value of pyroptosis-associated genes was assessed as a signature based on a cohort from TCGA (The Cancer Genome Atlas). Following Cox regression with DEGs and LASSO (least absolute shrinkage and selection operator), a 6-gene signature was established, and all ccRCC cases in the cohort from TCGA were categorized into an LR (low-risk) or HR (high-risk) group (P < 0.001). In combination with clinical features, risk scores were considered a predictive factor of OS in ccRCC. KEGG (Kyoto Encyclopedia of Genes and Genomes) and GO (Gene Ontology) analyses suggest increased immunity and enrichment of genes related to immunity in the HR group.

Conclusions

Our findings indicate that genes related to pyroptosis have an important role in tumour immunity and may be used to predict the prognosis of ccRCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01339-0.

Role of extracellular matrix architecture and signaling in melanoma therapeutic resistance

The extracellular matrix (ECM) is critical for maintaining tissue homeostasis therefore its production, assembly and mechanical stiffness are highly regulated in normal tissues. However, in solid tumors, increased stiffness resulting from abnormal ECM structural changes is associated with disease progression, an increased risk of metastasis and poor survival. As a dynamic and key component of the tumor microenvironment, the ECM is becoming increasingly recognized as an important feature of tumors, as it has been shown to promote several hallmarks of cancer via biochemical and biomechanical signaling. In this regard, melanoma cells are highly sensitive to ECM composition, stiffness and fiber alignment because they interact directly with the ECM in the tumor microenvironment via cell surface receptors, secreted factors or enzymes. Importantly, seeing as the ECM is predominantly deposited and remodeled by myofibroblastic stromal fibroblasts, it is a key avenue facilitating their paracrine interactions with melanoma cells. This review gives an overview of melanoma and further describes the critical roles that ECM properties such as ECM remodeling, ECM-related proteins and stiffness play in cutaneous melanoma progression, tumor cell plasticity and therapeutic resistance. Finally, given the emerging importance of ECM dynamics in melanoma, future perspectives on therapeutic strategies to normalize the ECM in tumors are discussed.

Construction of an immune-related gene signature for the prognosis and diagnosis of glioblastoma multiforme

Background

Increasing evidence has suggested that inflammation is related to tumorigenesis and tumor progression. However, the roles of immune-related genes in the occurrence, development, and prognosis of glioblastoma multiforme (GBM) remain to be studied.

Methods

The GBM-related RNA sequencing (RNA-seq), survival, and clinical data were acquired from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Chinese Glioma Genome Atlas (CGGA), and Gene Expression Omnibus (GEO) databases. Immune-related genes were obtained from the Molecular Signatures Database (MSigDB). Differently expressed immune-related genes (DE-IRGs) between GBM and normal samples were identified. Prognostic genes associated with GBM were selected by Kaplan–Meier survival analysis, Least Absolute Shrinkage and Selection Operator (LASSO)-penalized Cox regression analysis, and multivariate Cox analysis. An immune-related gene signature was developed and validated in TCGA and CGGA databases separately. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to explore biological functions of the signature. The correlation between immune cell infiltration and the signature was analyzed by single-sample gene set enrichment analysis (ssGSEA), and the diagnostic value was investigated. The gene set enrichment analysis (GSEA) was performed to explore the potential function of the signature genes in GBM, and the protein–protein interaction (PPI) network was constructed.

Results

Three DE-IRGs [Pentraxin 3 (PTX3), TNFSF9, and bone morphogenetic protein 2 (BMP2)] were used to construct an immune-related gene signature. Receiver operating characteristic (ROC) curves and Cox analyses confirmed that the 3-gene-based prognostic signature was a good independent prognostic factor for GBM patients. We found that the signature was mainly involved in immune-related biological processes and pathways, and multiple immune cells were disordered between the high- and low-risk groups. GSEA suggested that PTX3 and TNFSF9 were mainly correlated with interleukin (IL)-17 signaling pathway, nuclear factor kappa B (NF-κB) signaling pathway, tumor necrosis factor (TNF) signaling pathway, and Toll-like receptor signaling pathway, and the PPI network indicated that they could interact directly or indirectly with inflammatory pathway proteins. Quantitative real-time PCR (qRT-PCR) indicated that the three genes were significantly different between target tissues.

Conclusion

The signature with three immune-related genes might be an independent prognostic factor for GBM patients and could be associated with the immune cell infiltration of GBM patients.

Lupeol protects against cardiac hypertrophy via TLR4-PI3K-Akt-NF-κB pathways

Inflammation and apoptosis are main pathological processes that lead to the development of cardiac hypertrophy. Lupeol, a natural triterpenoid, has shown anti-inflammatory and anti-apoptotic activities as well as potential protective effects on cardiovascular diseases. In this study we investigated whether lupeol attenuated cardiac hypertrophy and fibrosis induced by pressure overload in vivo and in vitro, and explored the underlying mechanisms. Cardiac hypertrophy was induced in mice by transverse aortic constriction (TAC) surgery, and in neonatal rat cardiomyocytes (NRCMs) by stimulation with phenylephrine (PE) in vitro. We showed that administration of lupeol (50 mg ·kg^-1· d^-1, i.g., for 4 weeks) prevented the morphological changes and cardiac dysfunction and remodeling in TAC mice, and treatment with lupeol (50 μg/mL) significantly attenuated the hypertrophy of PE-stimulated NRCMs, and blunted the upregulated hypertrophic markers ANP, BNP, and β-MHC. Furthermore, lupeol treatment attenuated the apoptotic and inflammatory responses in the heart tissue. We revealed that lupeol attenuated the inflammatory responses including the reduction of inflammatory cytokines and inhibition of NF-κB p65 nuclear translocation, which was mediated by the TLR4-PI3K-Akt signaling. Administration of a PI3K/Akt agonist 740 Y-P reversed the protective effects of lupeol in TAC mice as well as in PE-stimulated NRCMs. Moreover, pre-treatment with a TLR4 agonist RS 09 abolished the protective effects of lupeol and restored the inhibition of PI3K-Akt-NF-κB signaling by lupeol in PE-stimulated NRCMs. Collectively, our results demonstrate that the lupeol protects against cardiac hypertrophy via anti-inflammatory mechanisms, which results from inhibiting the TLR4-PI3K-Akt-NF-κB signaling.

Neuropilin-2 axis in regulating secretory phenotype of neuroendocrine-like prostate cancer cells and its implication in therapy resistance

Neuroendocrine (NE)-like tumors secrete various signaling molecules to establish paracrine communication within the tumor milieu and to create a therapy-resistant environment. It is important to identify molecular mediators that regulate this secretory phenotype in NE-like cancer. The current study highlights the importance of a cell surface molecule, Neuropilin-2 (NRP2), for the secretory function of NE-like prostate cancer (PCa). Our analysis on different patient cohorts suggests that NRP2 is high in NE-like PCa. We have developed cell line models to investigate NRP2's role in NE-like PCa. Our bioinformatics, mass spectrometry, cytokine array, and other supporting experiments reveal that NRP2 regulates robust secretory phenotype in NE-like PCa and controls the secretion of factors promoting cancer cell survival. Depletion of NRP2 reduces the secretion of these factors and makes resistant cancer cells sensitive to chemotherapy in vitro and in vivo. Therefore, targeting NRP2 can revert cellular secretion and sensitize PCa cells toward therapy.

Polymorphisms in toll-like receptor 3 and 4 genes as prognostic and outcome biomarkers in melanoma patients

Melanoma is one of the most aggressive tumors, and in the setting of rising incidence and mortality, there is an urgent need to identify new prognostic markers. Toll-like receptors (TLRs), are aberrantly expressed in numerous cancers, including melanoma. TLR signaling provides a microenvironment that is involved in antitumor immune response, chronic inflammation, cancer cell proliferation and evasion of immune destruction. In the present study, we investigated whether single nucleotide polymorphisms (SNPs) in TLR3 and TLR4 genes are associated with clinicopathologic features, progression and survival of melanoma patients. The study was conducted on 120 melanoma patients. DNA extracted from peripheral blood was genotyped for TLR3 polymorphisms rs5743312 and rs3775291 (L412F) and TLR4 polymorphisms rs4986790 (D299G) and rs4986791 (T399I), by TaqMan Real-Time PCR Assays. Kaplan-Meier survival curves were compared by the log-rank test. TLR3 polymorphism L412F was associated with a higher mitotic index (P = 0.035). TLR4 D299G and T399I polymorphisms were associated with indicators of melanoma severity, nodal metastases (P = 0.005 and P = 0.007, respectively) and advanced stage III (P = 0.005 and P = 0.004, respectively). Cox regression analysis showed that the presence of tumor-infiltrating lymphocytes (TILs) predicted better overall survival (HR = 0.318; P = 0.004). TLR4 T399I polymorphism was significantly associated with worse survival, P = 0.025. The overall survival rates were significantly lower for patients carrying variant allele T of TLR4 T399I SNP (TC and TT genotypes combined) (P = 0.008, log-rank test), compared to wild-type genotype CC. Our findings indicate that TLR4 polymorphisms T399I (rs4986791) and D299G (rs4986790) could be potential prognostic and survival markers for melanoma patients.

Oxidative Stress and Inflammation Markers Associated with Multiple Peripheral Artery Occlusions in Elderly Patients

Background: Pro-oxidative stress and pro-inflammatory responses can influence each other in the development of atherosclerosis. This study evaluated the relationship between oxidative stress, inflammation, and multiple peripheral artery occlusions in elderly patients (age mean 71.2 ± 8.1 years). Methods: A total of 723 participants were enrolled: 67 healthy subjects, 214 patients with common iliac artery occlusions, 224 patients with popliteal artery occlusions, and 218 patients with femoral artery occlusions. We measured oxidative stress biomarkers (malondialdehyde [MDA], F2-isoprostane [F2-isoP], total oxidant status [TOS], and ischemia-modified albumin [IMA]) and the expressions of molecules in mimecan (MIME)/nuclear factor kappa B (NF-κB)/P53/Toll-like receptor 4 (TLR4) signaling pathway in older patients with multiple peripheral artery occlusions. Results: The levels of MDA, F2-isoP, TOS, IMA, MIME, NF-κB, P53, and TLR4 were increased in the single-site peripheral artery occlusive group when compared with healthy controls (P < .001) and were further increased in the multiple-site peripheral artery occlusive group compared with the single-site peripheral artery occlusive group (P < .001). Conclusion: Oxidative stress may promote inflammatory signaling pathways and lead to multiple peripheral artery occlusions in elderly patients.

STAT3 Activates the Pentraxin 3 Gene in Chronic Lymphocytic Leukemia Cells

Pentraxin-related protein 3 (PTX3), commonly produced by myeloid and endothelial cells, is a humoral pattern recognition protein of the innate immune system. Because PTX3 plasma levels of patients with chronic lymphocytic leukemia (CLL) are high and most circulating cells in patients with CLL are CLL cells, we reasoned that CLL cells produce PTX3. Western immunoblotting revealed that low-density cells from seven of seven patients with CLL produce high levels of PTX3, flow cytometry analysis revealed that the PTX3-producing cells are B lymphocytes coexpressing CD19 and CD5, and confocal microscopy showed that PTX3 is present in the cytoplasm of CLL cells. Because STAT3 is constitutively activated in CLL cells, and because we identified putative STAT3 binding sites within the PTX3 gene promoter, we postulated that phosphorylated STAT3 triggers transcriptional activation of PTX3. Immunoprecipitation analysis of CLL cells' chromatin fragments showed that STAT3 Abs precipitated PTX3 DNA. STAT3 knockdown induced a marked reduction in PTX3 expression, indicating a STAT3-induced transcriptional activation of the PTX3 gene in CLL cells. Using an EMSA, we established and used a dual-reporter luciferase assay to confirm that STAT3 binds the PTX3 gene promoter. Downregulation of PTX3 enhanced apoptosis of CLL cells, suggesting that inhibition of PTX3 might benefit patients with CLL.

PTX3 Protects Intestinal Mucosal Barrier Damage in Sepsis Through Toll-Like Receptor Signaling Pathway

This study aims to confirm the protective effect of Pentraxin 3 (PTX3) on intestinal mucosal barrier damage in sepsis in animal and cell models and explore its mechanism. Analysis of the GSE147775 gene set revealed that the level of PTX3 was upregulated in the lipopolysaccharide (LPS)-induced rat sepsis model. The mice sepsis model was established by cecal ligation perforation (CLP), and the cell inflammation model was induced by LPS. Cell apoptosis and the expression of apoptosis-related protein were detected by flow cytometry and Western blotting. The PTX3 level was significantly upregulated in the mice sepsis model. Intestinal mucosal barrier damage was aggravated and inflammatory factor expression was upregulated after PTX3 downregulation in sepsis mice. After upregulation of PTX3, intestinal mucosal barrier damage was alleviated and inflammatory factor expression was decreased in sepsis mice. Further data mining suggested that the anti-inflammatory effect of PTX3 might be realized through inhibition of the toll-like receptor (TLR) signaling pathway. Moreover, compared with the LPS group, downregulation of PTX3 increased cell apoptosis and the levels of BCL2-associated X (Bax), myeloperoxidase (MPO), tumor necrosis factor-alfa (TNF-α), interleukin 1 beta (IL-1β), and interferon-gamma (IFN-γ), and decreased the levels of B-cell lymphoma-2 (Bcl-2), zona occludens (ZO)-1, and occludin. On the contrary, overexpression of PTX3 reduced cell apoptosis and the levels of Bax, MPO, TNF-α, IL-1β, and IFN-γ. Moreover, downregulation of PTX3 reversed the inhibitive effects on cell apoptosis and inflammation and promotive effects on the levels of Zo-1 and occludin induced by CLI-095 (a TLR signaling pathway inhibitor). In the CLP-induced mice sepsis model and LPS-induced cell inflammation model, PTX3 inhibits inflammatory response and reduces intestinal mucosal barrier damage through the TLR signaling pathway.

NF-κB as a regulator of cancer metastasis and therapy response: A focus on epithelial-mesenchymal transition

Metastasis of tumor cells is a complex challenge and significantly diminishes the overall survival and prognosis of cancer patients. The epithelial-to-mesenchymal transition (EMT) is a well-known mechanism responsible for the invasiveness of tumor cells. A number of molecular pathways can regulate the EMT mechanism in cancer cells and nuclear factor-kappaB (NF-κB) is one of them. The nuclear translocation of NF-κB p65 can induce the transcription of several genes involved in EMT induction. The present review describes NF-κB and EMT interaction in cancer cells and their association in cancer progression. Due to the oncogenic role NF-κB signaling, its activation enhances metastasis of tumor cells via EMT induction. This has been confirmed in various cancers including brain, breast, lung and gastric cancers, among others. The ZEB1/2, transforming growth factor-β, and Slug as inducers of EMT undergo upregulation by NF-κB to promote metastasis of tumor cells. After EMT induction driven by NF-κB, a significant decrease occurs in E-cadherin levels, while N-cadherin and vimentin levels undergo an increase. The noncoding RNAs can potentially also function as upstream mediators and modulate NF-κB/EMT axis in cancers. Moreover, NF-κB/EMT axis is involved in mediating drug resistance in tumor cells. Thus, suppressing NF-κB/EMT axis can also promote the sensitivity of cancer cells to chemotherapeutic agents.

Secretion of IL1 by Dedifferentiated Melanoma Cells Inhibits JAK1-STAT3-Driven Actomyosin Contractility of Lymph Node Fibroblastic Reticular Cells

Fibroblastic reticular cells (FRC) are immunologically specialized myofibroblasts that control the elasticity of the lymph node, in part through their contractile properties. Swelling of tumor-draining lymph nodes is a hallmark of lymphophilic cancers such as cutaneous melanoma. Melanoma displays high intratumoral heterogeneity with the coexistence of melanoma cells with variable differentiation phenotypes from melanocytic to dedifferentiated states. Factors secreted by melanoma cells promote premetastatic lymph node reprograming and tumor spreading. Elucidating the impact of the melanoma secretome on FRC could help identify approaches to prevent metastasis. Here we show that melanocytic and dedifferentiated melanoma cells differentially impact the FRC contractile phenotype. Factors secreted by dedifferentiated cells, but not by melanocytic cells, strongly inhibited actomyosin-dependent contractile forces of FRC by decreasing the activity of the RHOA-RHO-kinase (ROCK) pathway and the mechano-responsive transcriptional coactivator Yes1 associated transcriptional regulator (YAP). Transcriptional profiling and biochemical analyses indicated that actomyosin cytoskeleton relaxation in FRC is driven by inhibition of the JAK1-STAT3 pathway. This FRC relaxation was associated with increased FRC proliferation and activation and with elevated tumor invasion in vitro. The secretome of dedifferentiated melanoma cells also modulated the biomechanical properties of distant lymph node in premetastatic mouse models. Finally, IL1 produced by dedifferentiated cells was involved in the inhibition of FRC contractility. These data highlight the role of the JAK1-STAT3 and YAP pathways in spontaneous contractility of resting FRC. They also suggest that dedifferentiated melanoma cells specifically target FRC biomechanical properties to favor tumor spreading in the premetastatic lymph node niche. Targeting this remote communication could be an effective strategy to prevent metastatic spread of the disease.

SIGNIFICANCE

Communication between dedifferentiated melanoma cells and lymph node fibroblasts reprograms the biomechanical properties of the premetastatic lymph node niche to promote tumor invasion. See related commentary by Lund, p. 1692.

The Role of Extracellular Matrix Remodeling in Skin Tumor Progression and Therapeutic Resistance

The extracellular matrix remodeling in the skin results from a delicate balance of synthesis and degradation of matrix components, ensuring tissue homeostasis. These processes are altered during tumor invasion and growth, generating a microenvironment that supports growth, invasion, and metastasis. Apart from the cellular component, the tumor microenvironment is rich in extracellular matrix components and bound factors that provide structure and signals to the tumor and stromal cells. The continuous remodeling in the tissue compartment sustains the developing tumor during the various phases providing matrices and proteolytic enzymes. These are produced by cancer cells and stromal fibroblasts. In addition to fostering tumor growth, the expression of specific extracellular matrix proteins and proteinases supports tumor invasion after the initial therapeutic response. Lately, the expression and structural modification of matrices were also associated with therapeutic resistance. This review will focus on the significant alterations in the extracellular matrix components and the function of metalloproteinases that influence skin cancer progression and support the acquisition of therapeutic resistance.

ADCK2 Knockdown Affects the Migration of Melanoma Cells via MYL6

Simple Summary

Melanoma is a growing health issue in the 21st century. Due to early metastasis and the development of resistance, it still goes along with a poor prognosis. ADCK protein kinases have been shown to play a role during cancer development and metastasis. Here, we investigated the role of ADCK2 in melanoma. In our study, we showed that higher levels of intratumoral ADCK2 benefit patient survival, while a low expression of ADCK2 was associated with a higher motility and a dedifferentiated state of melanoma cells, which facilitates metastasis. Our results could give new insights into melanoma metastasis, and ADCK2 could qualify as a prognostic marker or a target for melanoma therapy in the future.

Abstract

Background: ADCK2 is a member of the AarF domain-containing kinase family, which consists of five members, and has been shown to play a role in CoQ metabolism. However, ADCKs have also been connected to cancer cell survival, proliferation and motility. In this study, we investigated the role of ADCK2 in melanoma. Methods: The effect of ADCK2 on melanoma cell motility was evaluated by a scratch assay and a transwell invasion assay upon siRNA-mediated knockdown or stable overexpression of ADCK2. Results: We found that high levels of intratumoral ADCK2 and MYL6 are associated with a higher survival rate in melanoma patients. Knocking down ADCK2 resulted in enhanced cell migration of melanoma cells. Moreover, ADCK2-knockdown cells adopted a more dedifferentiated phenotype. A gene expression array revealed that the expression of ADCK2 correlated with the expressions of MYL6 and RAB2A. Knocking down MYL6 in ADCK2-overexpressing cells could abrogate the effect of ADCK2 overexpression and thus confirm the functional connection between ADCK2 and MYL6. Conclusion: ADCK2 affects melanoma cell motility, most probably via MYL6. Our results allow the conclusion that ADCK2 could act as a tumor suppressor in melanoma.

Blockade of the pro-fibrotic reaction mediated by the miR-143/-145 cluster enhances the responses to targeted therapy in melanoma

Lineage dedifferentiation toward a mesenchymal‐like state displaying myofibroblast and fibrotic features is a common mechanism of adaptive and acquired resistance to targeted therapy in melanoma. Here, we show that the anti‐fibrotic drug nintedanib is active to normalize the fibrous ECM network, enhance the efficacy of MAPK‐targeted therapy, and delay tumor relapse in a preclinical model of melanoma. Acquisition of this resistant phenotype and its reversion by nintedanib pointed to miR‐143/‐145 pro‐fibrotic cluster as a driver of this mesenchymal‐like phenotype. Upregulation of the miR‐143/‐145 cluster under BRAFi/MAPKi therapy was observed in melanoma cells in vitro and in vivo and was associated with an invasive/undifferentiated profile. The 2 mature miRNAs generated from this cluster, miR‐143‐3p and miR‐145‐5p, collaborated to mediate transition toward a drug‐resistant undifferentiated mesenchymal‐like state by targeting Fascin actin‐bundling protein 1 (FSCN1), modulating the dynamic crosstalk between the actin cytoskeleton and the ECM through the regulation of focal adhesion dynamics and mechanotransduction pathways. Our study brings insights into a novel miRNA‐mediated regulatory network that contributes to non‐genetic adaptive drug resistance and provides proof of principle that preventing MAPKi‐induced pro‐fibrotic stromal response is a viable therapeutic opportunity for patients on targeted therapy.

Screening of Autophagy-Related Prognostic Genes in Metastatic Skin Melanoma

Cutaneous melanoma refers to a common skin tumor that is dangerous to health with a great risk of metastasis. Previous researches reported that autophagy is associated with the progression of cutaneous melanoma. Nevertheless, the role played by genes with a relation to autophagy (ARG) in the prediction of the course of metastatic cutaneous melanoma is still largely unknown. We observed that thirteen ARGs showed relations to overall survival (OS) in the Cox regression investigation based on a single variate. We developed 2-gene signature, which stratified metastatic cutaneous melanoma cases to groups at great and small risks. Cases suffering from metastatic cutaneous melanoma in the group at great risks had power OS compared with cases at small risks. The risk score, T phase, N phase, and age were proved to be individual factors in terms of the prediction of OS. Besides, the risk scores identified by the two ARGs were significantly correlated with metastatic cutaneous melanoma. Receiver operating characteristic (ROC) curve analysis demonstrated accurate predicting performance exhibited by the 2-gene signature. We also found that the immunization and stromal scores achieved by the group based on large risks were higher compared with those achieved by the group based on small risks. The metastatic cutaneous melanoma cases achieving the score based on small risks acquired greater expression of immune checkpoint molecules as compared with the high-risk group. In conclusion, the 2-ARG gene signature indicated a novel prognostic indicator for prognosis prediction of metastatic cutaneous melanoma, which served as an important tool for guiding the clinical treatment of cutaneous melanoma.

Tumor cell intrinsic Toll-like receptor 4 signaling promotes melanoma progression and metastatic dissemination

Most melanoma-associated deaths result from the early development of metastasis. Toll-like receptor 4 (TLR4) expression on nontumor cells is well known to contribute to tumor development and metastatic progression. The role of TLR4 expression on tumor cells however is less well understood. Here we describe TLR4 as a driver of tumor progression and metastatic spread of melanoma cells by employing a transplantable mouse melanoma model. HCmel12 melanoma cells lacking functional TLR4 showed increased sensitivity to tumor necrosis factor α induced cell killing in vitro compared to cells with intact TLR4. Interestingly, TLR4 knockout melanoma cells also showed impaired migratory capacity in vitro and a significantly reduced ability to metastasize to the lungs after subcutaneous transplantation in vivo. Finally, we demonstrate that activation of TLR4 also promotes migration in a subset of human melanoma cell lines. Our work describes TLR4 as an important mediator of melanoma migration and metastasis and provides a rationale for therapeutic inhibition of TLR4 in melanoma.

Targeting Discoidin Domain Receptors DDR1 and DDR2 overcomes matrix-mediated tumor cell adaptation and tolerance to BRAF-targeted therapy in melanoma

Resistance to BRAF/MEK inhibitor therapy in BRAF^V600‐mutated advanced melanoma remains a major obstacle that limits patient benefit. Microenvironment components including the extracellular matrix (ECM) can support tumor cell adaptation and tolerance to targeted therapy; however, the underlying mechanisms remain poorly understood. Here, we investigated the process of matrix‐mediated drug resistance (MMDR) in response to BRAF^V600 pathway inhibition in melanoma. We demonstrate that physical and structural cues from fibroblast‐derived ECM abrogate anti‐proliferative responses to BRAF/MEK inhibition. MMDR is mediated by drug‐induced linear clustering of phosphorylated DDR1 and DDR2, two tyrosine kinase collagen receptors. Depletion and pharmacological targeting of DDR1 and DDR2 overcome ECM‐mediated resistance to BRAF‐targeted therapy. In xenografts, targeting DDR with imatinib enhances BRAF inhibitor efficacy, counteracts drug‐induced collagen remodeling, and delays tumor relapse. Mechanistically, DDR‐dependent MMDR fosters a targetable pro‐survival NIK/IKKα/NF‐κB2 pathway. These findings reveal a novel role for a collagen‐rich matrix and DDR in tumor cell adaptation and resistance. They also provide important insights into environment‐mediated drug resistance and a preclinical rationale for targeting DDR signaling in combination with targeted therapy in melanoma.

Diagnostic biomarkers of dilated cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) is a condition involving dilation of cardiac chambers, which results in contraction impairment. Besides invasive and non-invasive diagnostic procedures, cardiac biomarkers are of great importance in both diagnosis and prognosis of the disease. These biomarkers are categorized into three groups based on their site; cardiomyocyte biomarkers, microenvironmental biomarkers and macroenvironmental biomarkers.

AIMS

In this review, an overview of characteristics, epidemiology, etiology and clinical manifestations of DCM is provided. In addition, the most important biomarkers, of all three categories, and their diagnostic and prognostic values are discussed.

CONCLUSION

Considering the association of DCM with conditions such as infections and autoimmunity, which are prevalent among the population, introducing efficient diagnostic tools is of high value for the early detection of DCM to prevent its severe complications. The three discussed classes of biomarkers are potential candidates for the detection of DCM. However, further studies are necessary in this regard.

Autophagic secretion of HMGB1 from cancer-associated fibroblasts promotes metastatic potential of non-small cell lung cancer cells via NFκB signaling

Tumor progression requires the communication between tumor cells and tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are major components of stromal cells. CAFs contribute to metastasis process through direct or indirect interaction with tumor cells; however, the underlying mechanism is largely unknown. Here, we reported that autophagy was upregulated in lung cancer-associated CAFs compared to normal fibroblasts (NFs), and autophagy was responsible for the promoting effect of CAFs on non-small cell lung cancer (NSCLC) cell migration and invasion. Inhibition of CAFs autophagy attenuated their regulation on epithelial–mesenchymal transition (EMT) and metastasis-related genes of NSCLC cells. High mobility group box 1 (HMGB1) secreted by CAFs mediated CAFs’ effect on lung cancer cell invasion, demonstrated by using recombinant HMGB1, HMGB1 neutralizing antibody, and HMGB1 inhibitor glycyrrhizin (GA). Importantly, the autophagy blockade of CAFs revealed that HMGB1 release was dependent on autophagy. We also found HMGB1 was responsible, at least in part, for autophagy activation of CAFs, suggesting CAFs remain active through an autocrine HMGB1 loop. Further study demonstrated that HMGB1 facilitated lung cancer cell invasion by activating the NFκB pathway. In a mouse xenograft model, the autophagy specific inhibitor chloroquine abolished the stimulating effect of CAFs on tumor growth. These results elucidated an oncogenic function for secretory autophagy in lung cancer-associated CAFs that promotes metastasis potential, and suggested HMGB1 as a novel therapeutic target.

Circular RNA ZNF609 drives tumor progression by regulating the miR-138-5p/SIRT7 axis in melanoma

Melanoma serves as a prevailing and lethal skin malignancy with high mortality and a growing number of patients globally. Circular RNAs (circRNAs), as a type of emerging cellular regulator, are involved in the modulation of melanoma. Nevertheless, the function of circZNF609 in melanoma development remains obscure. In this study, we were interested in the effect and the underlying mechanism of circZNF609 on DNA damage during melanoma progression. The circZNF609 depletion significantly suppressed melanoma cell invasion, migration, and proliferation, and stimulated apoptosis. Meanwhile, comet assays showed that the tail length and γH2AX levels were elevated by circZNF609 depletion. Mechanically, circZNF609 sponged miR-138-5p and miR-138-5p targeted SIRT7 in the melanoma cells. The SIRT7 overexpression and miR-138-5p inhibitor could reverse circZNF609 depletion-mediated DNA damage and malignant progression in melanoma cells. Functionally, CircZNF609 promoted cell growth of melanoma in the nude mice. Consequently, we conclude that circZNF609 suppresses DNA damage and potentially enhances melanoma progression at the experimental condition by modulating the miR-138-5p/SIRT7 axis. Our finding provides new insights into the mechanism by which circZNF609 modulates the development of melanoma. CircZNF609 and miR-138-5p may be utilized as therapeutic targets for melanoma.

Development of a Four-mRNA Expression-Based Prognostic Signature for Cutaneous Melanoma

We aim to find a biomarker that can effectively predict the prognosis of patients with cutaneous melanoma (CM). The RNA sequencing data of CM was downloaded from The Cancer Genome Atlas (TCGA) database and randomly divided into training group and test group. Survival statistical analysis and machine-learning approaches were performed on the RNA sequencing data of CM to develop a prognostic signature. Using univariable Cox proportional hazards regression, random survival forest algorithm, and receiver operating characteristic (ROC) in the training group, the four-mRNA signature including CD276, UQCRFS1, HAPLN3, and PIP4P1 was screened out. The four-mRNA signature could divide patients into low-risk and high-risk groups with different survival outcomes (log-rank p < 0.001). The predictive efficacy of the four-mRNA signature was confirmed in the test group, the whole TCGA group, and the independent GSE65904 (log-rank p < 0.05). The independence of the four-mRNA signature in prognostic prediction was demonstrated by multivariate Cox analysis. ROC and timeROC analyses showed that the efficiency of the signature in survival prediction was better than other clinical variables such as melanoma Clark level and tumor stage. This study highlights that the four-mRNA model could be used as a prognostic signature for CM patients with potential clinical application value.

Pyroptosis-Related Gene Signatures Can Robustly Diagnose Skin Cutaneous Melanoma and Predict the Prognosis

Skin cutaneous melanoma (SKCM) is a chronically malignant tumor with a high mortality rate. Pyroptosis, a kind of pro-inflammatory programmed cell death, has been linked to cancer in recent studies. However, the value of pyroptosis in the diagnosis and prognosis of SKCM is not clear. In this study, it was discovered that 20 pyroptosis-related genes (PRGs) differed in expression between SKCM and normal tissues, which were related to diagnosis and prognosis. Firstly, based on these genes, nine machine-learning algorithms were shown to perform well in constructing diagnostic classifiers, including K-Nearest Neighbor (KNN), logistic regression, Support Vector Machine (SVM), Artificial Neural Network (ANN), decision tree, random forest, XGBoost, LightGBM, and CatBoost. Secondly, the least absolute shrinkage and selection operator (LASSO) Cox regression analysis was applied and the prognostic model was constructed based on 9 PRGs. Subgroups in low and high risks determined by the prognostic model were shown to have different survival. Thirdly, functional enrichment analyses were performed by applying the gene set enrichment analysis (GSEA), and results suggested that the risk was related to immune response. In conclusion, the expression signatures of pyroptosis-related genes are effective and robust in the diagnosis and prognosis of SKCM, which is related to immunity.

The Analysis of Inflammation-Related Proteins in a Cargo of Exosomes Derived from the Serum of Uveal Melanoma Patients Reveals Potential Biomarkers of Disease Progression

Simple Summary

Uveal melanoma (UM) is the most common intraocular tumour in adults with a poor prognosis and extremely high mortality rate due to the development of metastatic disease. Despite good knowledge of the histological and genetic background of metastases formation, there is still a lack of specific biomarkers which would allow early detection of UM progression. Due to their unique molecular cargo consisting of proteins and nucleic acids, exosomes have been widely studied as carriers of biomarkers for cancer development and progression. In this study, we analyzed the inflammation-related protein cargo of exosomes derived from the serum of primary and metastatic UM patients and healthy donors using multiplex immunoassay technology. We showed a significant correlation between the disease stage and the concentration of inflammation-related proteins from exosomal cargo. Based on the obtained results, we propose the panel of exosomal proteins for early detection of uveal melanoma progression into metastatic disease.

Abstract

Background: Uveal melanoma (UM) is the most common intraocular tumour in adults with a poor prognosis and extremely high mortality rate due to the development of metastatic disease. However, despite relatively good knowledge about the histological and genetic risk factors for metastasis development, there is no specific biomarker that would allow early detection of UM progression. Recently, exosomes and their molecular cargo have been widely studied in the search for potential biomarkers in several cancers. The purpose of this study was to analyze the inflammation-related protein cargo of exosomes derived from the serum of primary and metastatic UM patients and healthy donors. Methods: The exosomes were isolated from the serum of primary and metastatic UM patients and healthy donors. Using multiplex immunoassay technology, we analyzed the concentration of 37 inflammation-related proteins in obtained exosomes. Results: The analysis of protein cargo showed several molecules related to inflammation, such as interferon-gamma, interleukin 2, 22 and 12(p40), Pentraxin-3, TNFSF13B and TNFSF8 which were significantly enriched in metastatic UM exosomes. We showed a significant correlation between the disease stage and the concentration of these inflammation-related proteins from exosomal cargo. Conclusions: Based on the obtained results, we propose the panel of exosomal proteins for early detection of uveal melanoma progression into metastatic disease.

Establishment of a Novel In Vitro Model of Endometriosis with Oncogenic KRAS and PIK3CA Mutations for Understanding the Underlying Biology and Molecular Pathogenesis

Simple Summary

Endometriosis is a common gynecological condition that causes pelvic pain and infertility. Despite having normal histological features, several cells bear cancer-associated somatic mutations that result in local tissue invasion but rarely metastasize. Several cancer-associated genes, such as KRAS and PIK3CA, are frequently mutated in the endometriotic epithelium. However, the functional behavior and molecular pathogenesis of this disorder remain unclear. In this study, we developed an immortalized endometriotic epithelial cell line with mutations in KRAS and PIK3CA, which are genes associated with aggressive behaviors, such as increased cell migration, invasion, and proliferation. Through microarray analysis, the KRAS- and PIK3CA-specific gene signatures were identified; LOX and PTX3 were found to be responsible for this metastatic behavior. Knockdown of these two genes by siRNA markedly reduced the metastatic ability of the cells. Our findings suggest that inhibition of LOX and PTX3 may be an alternative therapeutic strategy to reduce the incidence of endometriosis.

Abstract

Endometriosis-harboring cancer-associated somatic mutations of PIK3CA and KRAS provides new opportunities for studying the multistep processes responsible for the functional and molecular changes in this disease. We aimed to establish a novel in vitro endometriosis model to clarify the functional behavior and molecular pathogenesis of this disorder. Immortalized HMOsisEC10 human ovarian endometriotic epithelial cell line was used in which KRAS and PIK3CA mutations were introduced. Migration, invasion, proliferation, and microarray analyses were performed using KRAS and PIK3CA mutant cell lines. In vitro assays showed that migration, invasion, and proliferation were significantly increased in KRAS and PIK3CA mutant cell lines, indicating that these mutations played causative roles in the aggressive behavior of endometriosis. Microarray analysis identified a cluster of gene signatures; among them, two significantly upregulated cancer-related genes, lysyl oxidase (LOX) and pentraxin3 (PTX3), were associated with cell proliferation, invasion, and migration capabilities. Furthermore, siRNA knockdown of the two genes markedly reduced the metastatic ability of the cells. These results suggest that endometriosis with KRAS or PIK3CA mutations can significantly enhance cell migration, invasion, and proliferation by upregulating LOX and PTX3. We propose that LOX and PTX3 silencing using small molecules could be an alternative therapeutic regimen for severe endometriosis.

In-depth proteomics analysis of sentinel lymph nodes from individuals with endometrial cancer

Endometrial cancer (EC) is one of the most common gynecological cancers worldwide. Sentinel lymph node (SLN) status could be a major prognostic factor in evaluation of EC, but several prospective studies need to be performed. Here we report an in-depth proteomics analysis showing significant variations in the SLN protein landscape in EC. We show that SLNs are correlated to each tumor grade, which strengthens evidence of SLN involvement in EC. A few proteins are overexpressed specifically at each EC tumor grade and in the corresponding SLN. These proteins, which are significantly variable in both locations, should be considered potential markers of overall survival. Five major proteins for EC and SLN (PRSS3, PTX3, ASS1, ALDH2, and ANXA1) were identified in large-scale proteomics and validated by immunohistochemistry. This study improves stratification and diagnosis of individuals with EC as a result of proteomics profiling of SLNs.

Pentraxin 3 acts as a functional effector of Akt/NF-κB signaling to modulate the progression and cisplatin-resistance in non-small cell lung cancer

Pentraxin 3 (PTX3) has been documented to be involved in the development of chemoresistance, however, the mechanisms by which it regulates cisplatin (DDP) resistance in non-small cell lung cancer (NSCLC) have never been elucidated. Quantitative reverse transcriptase polymerase chain reaction and Western blot were carried to determine the expression of PTX3, ATP-binding cassette sub-family B member 1 (ABCB1)/P-glycoprotein 1 (p-gp), protein kinase B (Akt), phosphorylated Akt and nuclear factor-kappa B (NF-кB) p65. The biological roles of PTX3 in NSCLC progression and NSCLC cell resistance to DDP were evaluated using enzyme-linked immunosorbent assay, cell count kit-8, colony formation assay, flow cytometry, as well as xenograft tumor assay. The expression of PTX3 was increased in the serum of NSCLC patients as well as in NSCLC cell lines. Lower PTX3 level was associated with longer overall survival in lung adenocarcinoma and lung squamous cell carcinoma patients. Furthermore, PTX3 expression was greatly higher in DDP-resistant NSCLC cells than that in NSCLC cells. Silencing of PTX3 restrained the proliferation and promoted the apoptosis of NSCLC cells, as well as sensitized DDP-resistant NSCLC cells to DDP. Additionally, knockdown of PTX3 inhibited the growth of NSCLC tumors in vivo. Upregulation of PTX3 expression was dependent on the activation of Akt/NF-κB signaling. The induction of apoptosis by PTX3 knockdown was enhanced by MK-2206 or JSH-23. In conclusion, knockdown of PTX3 restrained the progression of NSCLC and sensitized NSCLC cells towards DDP, which provides a potential target to restore DDP chemoresponse.

Integrated Bioinformatics Analysis Exhibits Pivotal Exercise-Induced Genes and Corresponding Pathways in Malignant Melanoma

Malignant melanoma represents a sort of neoplasm deriving from melanocytes or cells developing from melanocytes. The balance of energy and energy-associated body composition and body mass index could be altered by exercise, thereby directly affecting the microenvironment of neoplasm. However, few studies have examined the mechanism of genes induced by exercise and the pathways involved in melanoma. This study used three separate datasets to perform comprehensive bioinformatics analysis and then screened the probable genes and pathways in the process of exercise-promoted melanoma. In total, 1,627 differentially expressed genes (DEGs) induced by exercise were recognized. All selected genes were largely enriched in NF-kappa B, Chemokine signaling pathways, and the immune response after gene set enrichment analysis. The protein-protein interaction network was applied to excavate DEGs and identified the most relevant and pivotal genes. The top 6 hub genes (Itgb2, Wdfy4, Itgam, Cybb, Mmp2, and Parp14) were identified, and importantly, 5 hub genes (Itgb2, Wdfy4, Itgam, Cybb, and Parp14) were related to weak disease-free survival and overall survival (OS). In conclusion, our findings demonstrate the prognostic value of exercise-induced genes and uncovered the pathways of these genes in melanoma, implying that these genes might act as prognostic biomarkers for melanoma.

Venom peptides in cancer therapy: An updated review on cellular and molecular aspects

Based on the high incidence and mortality rates of cancer, its therapy remains one of the most vital challenges in the field of medicine. Consequently, enhancing the efficacy of currently applied treatments and finding novel strategies are of great importance for cancer treatment. Venoms are important sources of a variety of bioactive compounds including salts, small molecules, macromolecules, proteins, and peptides that are defined as toxins. They can exhibit different pharmacological effects, and in recent years, their anti-tumor activities have gained significant attention. Several different compounds are responsible for the anti-tumor activity of venoms, and peptides are one of them. In the present review, we discuss the possible anti-tumor activities of venom peptides by highlighting molecular pathways and mechanisms through which these molecules can act effectively. Venom peptides can induce cell death in cancer cells and can substantially enhance the efficacy of chemotherapy and radiotherapy. Also, the venom peptides can mitigate the migration of cancer cells via suppression of angiogenesis and epithelial-to-mesenchymal transition. Notably, nanoparticles have been applied in enhancing the bioavailability of venom peptides and providing targeted delivery, thereby leading to their elevated anti-tumor activity and potential application for cancer therapy.

Hypoxia-Inducible Ubiquitin Specific Peptidase 13 Contributes to Tumor Growth and Metastasis via Enhancing the Toll-Like Receptor 4/Myeloid Differentiation Primary Response Gene 88/Nuclear Factor-κB Pathway in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. The activation of the toll-like receptor 4/myeloid differentiation primary response gene 88/nuclear factor-κB (TLR4/MyD88/NF-κB) pathway contributes to the development and progression of HCC. The ubiquitin-proteasome system regulates TLR4 expression. However, whether ubiquitin specific peptidase 13 (USP13) stabilizes TLR4 and facilitates HCC progression remains unclear. Here, quantitative real-time PCR (qRT-PCR) and immunohistochemistry analysis revealed that USP13 expression in HCC tissues was higher than in non-tumor liver tissues. Moreover, the elevated expression of USP13 was detected in HCC cells (SK-HEP-1, HepG2, Huh7, and Hep3B) compared to LO2 cells. Interestingly, the positive staining of USP13 was closely correlated with tumor size ≥ 5 cm and advanced tumor stage and conferred to significantly lower survival of HCC patients. Next, USP13 knockdown prominently reduced the proliferation, epithelial-mesenchymal transition (EMT), migration, and invasion of Hep3B and Huh7 cells, while USP13 overexpression enhanced these biological behaviors of HepG2 and LO2 cells. The silencing of USP13 significantly restrained the growth and lung metastasis of HCC cells in vivo. Mechanistically, the USP13 depletion markedly inhibited the TLR4/MyD88/NF-κB pathway in HCC cells. USP13 interacted with TLR4 and inhibited the ubiquitin-mediated degradation of TLR4. Significantly, TLR4 re-expression remarkably reversed the effects of USP13 knockdown on HCC cells. USP13 expression was markedly upregulated in HCC cells under hypoxia conditions. Notably, USP13 knockdown repressed hypoxia-induced activation of the TLR4/MyD88/NF-κB pathway in HCC cells. In conclusion, our study uncovered that hypoxia-induced USP13 facilitated HCC progression via enhancing TLR4 deubiquitination and subsequently activating the TLR4/MyD88/NF-κB pathway.

Single-cell transcriptome atlas of lung adenocarcinoma featured with ground glass nodules

As an early type of lung adenocarcinoma, ground glass nodule (GGN) has been detected increasingly and now accounts for most lung cancer outpatients. GGN has a satisfactory prognosis and its characteristics are quite different from solid adenocarcinoma (SADC). We compared the GGN adenocarcinoma (GGN-ADC) with SADC using the single-cell RNA sequencing (scRNA-seq) to fully understand GGNs. The tumor samples of five patients with lung GGN-ADCs and five with SADCs underwent surgery were digested to a single-cell suspension and analyzed using 10× Genomic scRNA-seq techniques. We obtained 60,459 cells and then classified them as eight cell types, including cancer cells, endothelial cells, fibroblasts, T cells, B cells, Nature killer cells, mast cells, and myeloid cells. We provided a comprehensive description of the cancer cells and stromal cells. We found that the signaling pathways related to cell proliferation were downregulated in GGN-ADC cancer cells, and stromal cells had different effects in GGN-ADC and SADC based on the analyses of scRNA-seq results. In GGN-ADC, the signaling pathways of angiogenesis were downregulated, fibroblasts expressed low levels of some collagens, and immune cells were more activated. Furthermore, we used flow cytometry to isolate the cancer cells and T cells in 12 GGN-ADC samples and in an equal number of SADC samples, including CD4+ T and CD8+ T cells, and validated the expression of key molecules by quantitative real-time polymerase chain reaction analyses. Through comprehensive analyses of cell phenotypes in GGNs, we provide deep insights into lung carcinogenesis that will be beneficial in lung cancer prevention and therapy.