FADD protein release mirrors the development and aggressiveness of human non-small cell lung cancer

FADD amplification is associated with CD8+ T-cell exclusion and malignant progression in HNSCC

OBJECTIVE

This study aimed to clarify the relationship between FADD amplification and overexpression and the tumor immune microenvironment.

METHODS

Immunohistochemical staining and bioanalysis were used to analyze the association between FADD expression in tumor cells and cells in tumor microenvironment. RNA-seq analysis was used to detect the differences in gene expression upon FADD overexpression. Flow cytometry and multicolor immunofluorescence staining (mIHC) were used to detect the differences in CD8+ T-cell infiltration in FADD-overexpressed cells or tumor tissues.

RESULTS

Overexpression of FADD significantly promoted tumor growth. Cells with high FADD expression presented high expression of CD276 and FGFBP1 and low expression of proinflammatory factors (such as IFIT1-3 and CXCL8), which reduced the percentage of CD8+ T cells and created a "cold tumor" immune microenvironment, thus promoting tumor progression. In vivo and in vitro experiment confirmed that tumor tissues with excessive FADD expression exhibited CD8+ T-cell exclusion in the microenvironment.

CONCLUSION

Our preliminary investigation has discovered the association between FADD expression and the immunosuppressive microenvironment in HNSCC. Due to the high frequent amplification of the chromosomal region 11q13.3, where FADD is located, targeting FADD holds promise for improving the immune-inactive state of tumors, subsequently inhibiting HNSCC tumor progression.

The PANoptosis-related signature indicates the prognosis and tumor immune infiltration features of gliomas

Background

Gliomas are the most common primary tumors of the central nervous system, with high heterogeneity and highly variable survival rates. Accurate classification and prognostic assessment are key to the selection of treatment strategies. One hallmark of the tumor is resistance to cell death. PANoptosis, a novel mode of programmed cell death, has been frequently reported to be involved in the innate immunity associated with pathogen infection and played an important role in cancers. However, the intrinsic association of PANoptosis with glioma requires deeper investigation.

Methods

The genetics and expression of the 17 reported PANoptosome-related genes were analyzed in glioma. Based on these genes, patients were divided into two subtypes by consensus clustering analysis. After obtaining the differentially expressed genes between clusters, a prognostic model called PANopotic score was constructed after univariate Cox regression, LASSO regression, and multivariate Cox regression. The expression of the 5 genes included in the PANopotic score was also examined by qPCR in our cohort. The prognostic differences, clinical features, TME infiltration status, and immune characteristics between PANoptotic clusters and score groups were compared, some of which even extended to pan-cancer levels.

Results

Gene mutations, CNVs and altered gene expression of PANoptosome-related genes exist in gliomas. Two PANoptotic clusters were significantly different in prognosis, clinical features, immune characteristics, and mutation landscapes. The 5 genes included in the PANopotic score had significantly altered expression in glioma samples in our cohort. The high PANoptotic score group was inclined to show an unfavorable prognosis, lower tumor purity, worse molecular genetic signature, and distinct immune characteristics related to immunotherapy. The PANoptotic score was considered as an independent prognostic factor for glioma and showed superior prognostic assessment efficacy over several reported models. PANopotic score was included in the nomogram constructed for the potential clinical prognostic application. The associations of PANoptotic score with prognostic assessment and tumor immune characteristics were also reflected at the pan-cancer level.

Conclusion

Molecular subtypes of glioma based on PANoptosome-related genes were proposed and PANoptotic score was constructed with different clinical characteristics of anti-tumor immunity. The potential intrinsic association between PANoptosis and glioma subtypes, prognosis, and immunotherapy was revealed.

Prognostic significance and immune correlates of FADD in penile squamous cell carcinoma

Penile squamous cell carcinoma (PSCC) with a poor prognosis lacks reliable biomarkers for stratifying patients. Fas-associated death domain (FADD) could regulate cell proliferation and has shown promising diagnostic and prognostic significance in multiple cancers. However, researchers have not determined how FADD exerts its effect on PSCC. In this study, we set out to investigate the clinical features of FADD and the prognostic impact of PSCC. Additionally, we also assessed the role of affecting the immune environment in PSCC. Immunohistochemistry was carried out to evaluate the protein expression of FADD. The difference between FADD^high and FADD^low was explored by RNA sequencing from available cases. The immune environment evaluation of CD4, CD8, and Foxp3 was performed by immunohistochemical. In this study, we found that FADD was overexpressed in 19.6 (39/199) patients, and the overexpression of FADD was associated with phimosis (p=0.007), N stage (p<0.001), clinical stage (p=0.001), and histologic grade (p=0.005). The overexpression of FADD was an independent prognostic factor for both PFS (HR 3.976, 95% CI 2.413-6.553, p<0.001) and OS (HR 4.134, 95% CI 2.358-7.247, p<0.001). In addition, overexpression of FADD was mainly linked to T cell activation and PD-L1 expression combined with PD-L1 checkpoint in cancer. Further validation demonstrated that overexpression of FADD was positively correlated with the infiltration of Foxp3 in PSCC (p=0.0142). It is the first time to show that overexpression of FADD is an adjunct biomarker with poor prognosis in PSCC and could also serve as a tumor immune environment regulator.

A Dual Role for FADD in Human Precursor T-Cell Neoplasms

A reduction in FADD levels has been reported in precursor T-cell neoplasms and other tumor types. Such reduction would impact on the ability of tumor cells to undergo apoptosis and has been associated with poor clinical outcomes. However, FADD is also known to participate in non-apoptotic functions, but these mechanisms are not well-understood. Linking FADD expression to the severity of precursor T-cell neoplasms could indicate its use as a prognostic marker and may open new avenues for targeted therapeutic strategies. Using transcriptomic and clinical data from patients with precursor T-cell neoplasms, complemented by in vitro analysis of cellular functions and by high-throughput interactomics, our results allow us to propose a dual role for FADD in precursor T-cell neoplasms, whereby resisting cell death and chemotherapy would be a canonical consequence of FADD deficiency in these tumors, whereas deregulation of the cellular metabolism would be a relevant non-canonical function in patients expressing FADD. These results reveal that evaluation of FADD expression in precursor T-cell neoplasms may aid in the understanding of the biological processes that are affected in the tumor cells. The altered biological processes can be of different natures depending on the availability of FADD influencing its ability to exert its canonical or non-canonical functions. Accordingly, specific therapeutic interventions would be needed in each case.

FADD as a key molecular player in cancer progression

Cancer is a leading disease-related cause of death worldwide. Despite advances in therapeutic interventions, cancer remains a major global public health problem. Cancer pathogenesis is extremely intricate and largely unknown. Fas-associated protein with death domain (FADD) was initially identified as an adaptor protein for death receptor-mediated extrinsic apoptosis. Recent evidence suggests that FADD plays a vital role in non-apoptotic cellular processes, such as proliferation, autophagy, and necroptosis. FADD expression and activity of are modulated by a complicated network of processes, such as DNA methylation, non-coding RNA, and post-translational modification. FADD dysregulation has been shown to be closely associated with the pathogenesis of numerous types of cancer. However, the detailed mechanisms of FADD dysregulation involved in cancer progression are still not fully understood. This review mainly summarizes recent findings on the structure, functions, and regulatory mechanisms of FADD and focuses on its role in cancer progression. The clinical implications of FADD as a biomarker and therapeutic target for cancer patients are also discussed. The information reviewed herein may expand researchers’ understanding of FADD and contribute to the development of FADD-based therapeutic strategies for cancer patients.

Analyzing integrated network of methylation and gene expression profiles in lung squamous cell carcinoma

Gene expression, DNA methylation, and their organizational relationships are commonly altered in lung squamous cell carcinoma (LUSC). To elucidate these complex interactions, we reconstructed a differentially expressed gene network and a differentially methylated cytosine (DMC) network by partial information decomposition and an inverse correlation algorithm, respectively. Then, we performed graph union to integrate the networks. Community detection and enrichment analysis of the integrated network revealed close interactions between the cell cycle, keratinization, immune system, and xenobiotic metabolism gene sets in LUSC. DMC analysis showed that hypomethylation targeted the gene sets responsible for cell cycle, keratinization, and NRF2 pathways. On the other hand, hypermethylated genes affected circulatory system development, the immune system, extracellular matrix organization, and cilium organization. By centrality measurement, we identified NCAPG2, PSMG3, and FADD as hub genes that were highly connected to other nodes and might play important roles in LUSC gene dysregulation. We also found that the genes with high betweenness centrality are more likely to affect patients’ survival than those with low betweenness centrality. These results showed that the integrated network analysis enabled us to obtain a global view of the interactions and regulations in LUSC.

AK2 Promotes the Migration and Invasion of Lung Adenocarcinoma by Activating TGF-β/Smad Pathway In vitro and In vivo

Adenylate kinase 2 (AK2) is a wide-spread and highly conserved protein kinase whose main function is to catalyze the exchange of nucleotide phosphate groups. In this study, we showed that AK2 regulated tumor cell metastasis in lung adenocarcinoma. Positive expression of AK2 is related to lung adenocarcinoma progression and poor survival of patients. Knockdown or knockout of AK2 inhibited, while overexpression of AK2 promoted, human lung adenocarcinoma cell migration and invasion ability. Differential proteomics results showed that AK2 might be closely related to epithelial-mesenchymal transition (EMT). Further research indicated that AK2 regulated EMT occurrence through the Smad-dependent classical signaling pathways as measured by western blot and qPCR assays. Additionally, in vivo experiments showed that AK2-knockout in human lung tumor cells reduced their EMT-like features and formed fewer metastatic nodules both in liver and in lung tissues. In conclusion, we uncover a cancer metastasis-promoting role for AK2 and provide a rationale for targeting AK2 as a potential therapeutic approach for lung cancer.

Overexpression of FADD and Bcl-XS proteins as novel prognostic biomarkers for surgically resected non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is one of the most widespread cancer with increasing morbidity and mortality. FAS-associated protein with death domain (FADD) is considered as an essential instrument in cell death, whereas Bcl-XS promotes apoptosis through inhibiting the activity of Bcl-2 and Bcl-XL.

OBJECTIVE AND METHODS

We detected the expression of FADD and Bcl-XS in resected NSCLC tissues by immunohistochemistry, and investigated their association with clinicopathological characteristics and prognostic significance of NSCLC patients.

RESULTS

Bcl-XS expression was significantly increased in well and moderate differentiated lung SCC (P= 0.004). Lung ADC patients with overexpression of FADD and lung SCC patients with low expression of Bcl-XS had importantly lower overall survival rates by Kaplan-Meier analysis (P= 0.033, P= 0.02, respectively). Multivariate analysis confirmed that elevated expression of FADD was an independent poor prognostic factor for patients with surgically resected lung ADC (P= 0.027) and increased expression of Bcl-XS was an independent good prognostic factor for patients with surgically resected lung SCC (P= 0.016)CONCLUSION: Elevated expression of FADD was identified as independent poor prognostic factor for patients with surgically resected lung ADC, however, increased expression of Bcl-XS was an independent good prognostic biomarker for patients with surgically resected lung SCC.

Development and biological evaluation of[18F]FMN3PA & [18F]FMN3PU for leucine-rich repeat kinase 2 (LRRK2) in vivo PET imaging

PURPOSE

Among all genetic mutations of LRRK2, the G2019S mutation is the most commonly associated with the late-onset of Parkinson's disease (PD). Hence, one potential therapeutic approach is to block the hyperactivity of mutated LRRK2 induced by kinase inhibition. To date, only a few LRRK2 kinase inhibitors have been tested for in vivo quantification of target engagement by positron emission tomography (PET). In this study, we performed biological evaluations of two radiolabeled kinase inhibitors i.e. [¹⁸F]FMN3PA (14) and [¹⁸F]FMN3PU for LRRK2 (15).

PROCEDURES

Radiosyntheses of [¹⁸F]FMN3PA (14) and [¹⁸F]FMN3PU (15) were performed using K[¹⁸F]-F-K222 complex in a TRACERlab FXN module and purification was carried out via C18 plus (Sep-Pak) cartridges. In vitro specific binding assays were performed in rat brain striatum and kidney tissues using GNE-0877 as a blocking agent (K_i = 0.7 nM). For in vivo blocking, 3 mg/kg of GNE-0877 was injected 30 min before radiotracer injection via tail vein in wild-type (WT) mice (n = 4). Dynamic scans by PET/CT (Siemens Inveon) were performed in WT mice (n = 3).

RESULTS

Radiofluorinations resulted in radiochemical yields (RCYs) of 25 ± 1.3% (n = 6) ([¹⁸F]FMN3PU, 15) and 37 ± 1.6% (n = 6) ([¹⁸F]FMN3PA, 14) with ≥96% radiochemical purity (RCP) and a molar activity (MA) of 3.55 ± 1.6 Ci/μmol (131 ± 56 GBq/μmol) for [¹⁸F]FMN3PU (15) and 4.57 ± 1.7 Ci/μmol (169 ± 63 GBq/μmol) for [¹⁸F]FMN3PA (14), respectively. Saturation assays showed high specific binding for rat brain striatum with K_d 20 ± 1.3 nM ([¹⁸F]FMN3PA, 14) and 23.6 ± 4.0 nM ([¹⁸F]FMN3PU, 15). In vivo blocking data for [¹⁸F]FMN3PA (14) was significant for brain (p < 0.0001, 77% blocking) and kidney (p = 0.0041, 65% blocking). PET images showed uptake in mouse brain striatum.

CONCLUSION

In the presence of GNE-0877 as a blocking agent, the specific binding of [¹⁸F]FMN3PA (14) and [¹⁸F]FMN3PU (15) was significant in vitro. [¹⁸F]FMN3PA (14) showed good brain uptake in vivo, though fast clearance from brain was observed (within 10-15 min).

Cell-Penetrable Peptide-Conjugated FADD Induces Apoptosis and Regulates Inflammatory Signaling in Cancer Cells

Dysregulated expression of Fas-associated death domain (FADD) is associated with the impediment of various cellular pathways, including apoptosis and inflammation. The adequate cytosolic expression of FADD is critical to the regulation of cancer cell proliferation. Importantly, cancer cells devise mechanisms to suppress FADD expression and, in turn, escape from apoptosis signaling. Formulating strategies, for direct delivery of FADD proteins into cancer cells in a controlled manner, may represent a promising therapeutic approach in cancer therapy. We chemically conjugated purified FADD protein with cell permeable TAT (transactivator of transcription) peptide, to deliver in cancer cells. TAT-conjugated FADD protein internalized through the caveolar pathway of endocytosis and retained in the cytosol to augment cell death. Inside cancer cells, TAT-FADD rapidly constituted DISC (death inducing signaling complex) assembly, which in turn, instigate apoptosis signaling. The apoptotic competency of TAT-FADD showed comparable outcomes with the conventional apoptosis inducers. Notably, TAT-FADD mitigates constitutive NF-κB activation and associated downstream anti-apoptotic genes Bcl2, cFLIP_L, RIP1, and cIAP2, independent of pro-cancerous TNF-α priming. In cancer cells, TAT-FADD suppresses the canonical NLRP3 inflammasome priming and restricts the processing and secretion of proinflammatory IL-1β. Our results demonstrate that TAT-mediated intracellular delivery of FADD protein can potentially recite apoptosis signaling with simultaneous regulation of anti-apoptotic and proinflammatory NF-κB signaling activation in cancer cells.

Development of an autophagy-related gene prognostic signature in lung adenocarcinoma and lung squamous cell carcinoma

Purpose

There is plenty of evidence showing that autophagy plays an important role in the biological process of cancer. The purpose of this study was to establish a novel autophagy-related prognostic marker for lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC).

Methods

The mRNA microarray and clinical data in The Cancer Genome Atlas (TCGA) were analyzed by using a univariate Cox proportional regression model to select candidate autophagy-related prognostic genes. Bioinformatics analysis of gene function using the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) platforms was performed. A multivariate Cox proportional regression model helped to develop a prognostic signature from the pool of candidate genes. On the basis of this prognostic signature, we could divide LUAD and LUSC patients into high-risk and low-risk groups. Further survival analysis demonstrated that high-risk patients had significantly shorter disease-free survival (DFS) than low-risk patients. The signature which contains six autophagy-related genes (EIF4EBP1, TP63, BNIP3, ATIC, ERO1A and FADD) showed good performance for predicting the survival of LUAD and LUSC patients by having a better Area Under Curves (AUC) than other clinical parameters. Its efficacy was also validated by data from the Gene Expression Omnibus (GEO) database.

Conclusion

Collectively, the prognostic signature we proposed is a promising biomarker for monitoring the outcomes of LUAD and LUSC.

Association between ANGPTL-4 and the proinflammatory process in cancer cachexia patients

Background

Contradictory results are reported for the role of angiopoietin-like 4 (ANGPTL-4) in the development of cancer-cachexia and inflammation, given its importance in angiogenesis and inflammatory signaling. Our aim was to analyze the levels of ANGPTL-4 in colorectal cancer patients with a stable weight and those with cachexia in order to establish a relationship between ANGPTL-4 and the inflammatory process.

Results

Plasma and tumor levels of ANGPTL-4 were higher in CC in comparison to other groups. A positive association was verified between plasmatic ANGPTL-4 and NFκB levels in tumor from CC. In WSC, we identified an association between the plasmatic ANGPTL-4, IL-15, and IL-10 in tumor and IL-15 in MES. Increased levels of NFκB and TNF-R1 in MES were detected in CC in comparison to WSC. Specifically in CC-group, a positive correlation was found between ANGPTL-4 levels and those of IL-1β, TNF-α, and NFκB in tumor, along with an association between ANGPTL-4 levels with IL-1β and MCP-1 levels in tumor; and ANGPTL-4 and IL-1β levels in MES.

Methods

We studied 102 patients, who were divided into three groups: control patients (C, n=37), cancer patients with a stable weight (WSC, n=23), and cancer-cachexia patients (CC, n=42). Samples of plasma, tumor, mesenteric (MES) and subcutaneous adipose tissue were removed for the determination of ANGPTL-4 levels and other proinflammatory factors.

Conclusions

ANGPTL-4 levels were higher in plasma and tumor of CC-group, and positively associated with pro-inflammatory and pro-tumorigenic factors. Our results suggest an opposite effect of ANGPTL-4 depending on the concentration and presence of cachexia.

FADD in Cancer: Mechanisms of Altered Expression and Function, and Clinical Implications

FADD was initially described as an adaptor molecule for death receptor-mediated apoptosis, but subsequently it has been implicated in nonapoptotic cellular processes such as proliferation and cell cycle control. During the last decade, FADD has been shown to play a pivotal role in most of the signalosome complexes, such as the necroptosome and the inflammasome. Interestingly, various mechanisms involved in regulating FADD functions have been identified, essentially posttranslational modifications and secretion. All these aspects have been thoroughly addressed in previous reviews. However, FADD implication in cancer is complex, due to pleiotropic effects. It has been reported either as anti- or protumorigenic, depending on the cell type. Regulation of FADD expression in cancer is a complex issue since both overexpression and downregulation have been reported, but the mechanisms underlying such alterations have not been fully unveiled. Posttranslational modifications also constitute a relevant mechanism controlling FADD levels and functions in tumor cells. In this review, we aim to provide detailed, updated information on alterations leading to changes in FADD expression and function in cancer. The participation of FADD in various biological processes is recapitulated, with a mention of interesting novel functions recently proposed for FADD, such as regulation of gene expression and control of metabolic pathways. Finally, we gather all the available evidence regarding the clinical implications of FADD alterations in cancer, especially as it has been proposed as a potential biomarker with prognostic value.

Prognostic value of biomarkers EpCAM and αB-crystallin associated with lymphatic metastasis in breast cancer by iTRAQ analysis

Background

Metastasis is responsible for the majority of deaths in a variety of cancer types, including breast cancer. Although several factors or biomarkers have been identified to predict the outcome of patients with breast cancer, few studies have been conducted to identify metastasis-associated biomarkers.

Methods

Quantitative iTRAQ proteomics analysis was used to detect differentially expressed proteins between lymph node metastases and their paired primary tumor tissues from 23 patients with metastatic breast cancer. Immunohistochemistry was performed to validate the expression of two upregulated (EpCAM, FADD) and two downregulated (NDRG1, αB-crystallin) proteins in 190 paraffin-embedded tissue samples. These four proteins were further analyzed for their correlation with clinicopathological features in 190 breast cancer patients.

Results

We identified 637 differentially regulated proteins (397 upregulated and 240 downregulated) in lymph node metastases compared with their paired primary tumor tissues. Data are available via ProteomeXchange with identifier PXD013931. Furthermore, bioinformatics analysis using GEO profiling confirmed the difference in the expression of EpCAM between metastases and primary tumors tissues. Two upregulated (EpCAM, FADD) and two downregulated (NDRG1, αB-crystallin) proteins were associated with the progression of breast cancer. Obviously, EpCAM plays a role in the metastasis of breast cancer cells to the lymph node. We further identified αB-crystallin as an independent biomarker to predict lymph node metastasis and the outcome of breast cancer patients.

Conclusion

We have identified that EpCAM plays a role in the metastasis of breast cancer cells to the lymph node. αB-crystallin, a stress-related protein that has recently been shown to be important for cell invasion and survival, was identified as a potential prognostic biomarker to predict the outcome of breast cancer patients.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-6016-3) contains supplementary material, which is available to authorized users.

Effect of food intake on 92 oncological biomarkers by the Proseek Oncology II panel

Objective

To evaluates the effect of food intake on 92 oncological biomarkers to evaluate whether the timing of blood sampling could be relevant. Twenty-two healthy subjects were investigated. A total of 92 biomarkers were measured before a standardised meal as well as 30 and 120 min afterwards with the Proseek Multiplex Oncology II kit.

Results

The levels of 6 biomarkers decreased significantly (P < 0.001) 30 min after food intake, and 4 biomarkers remained decreased (P < 0.001) 120 min after food intake. One biomarker was significantly increased (P < 0.001) at both 30 and 120 min after food intake. Some changes were less than 10%. Those biomarkers that showed a difference of more than 10% include: Granzyme H (13%), Methionine aminopeptidase 2 (14%), Secretory carrier-associated membrane protein 3 (39%), FAS-associated death domain protein (41%), and Pancreatic prohormone (79%). This study shows that food intake has a very modest effect on 92 different oncological biomarkers.

Trial registration National Library of Medicine trial registration number NCT01027507 (retrospectively registered on December 8, 2009)

S194-P-FADD as a marker of aggressiveness and poor prognosis in human T-cell lymphoblastic lymphoma

T-cell lymphoblastic lymphoma is a haematological disease with an urgent need for reliable prognostic biomarkers that allow therapeutic stratification and dose adjustment. The scarcity of human samples is responsible for the delayed progress in the study and the clinical management of this disease, especially compared with T-cell acute lymphoblastic leukaemia, its leukemic counterpart. In the present work, we have determined by immunohistochemistry that S194-P-FADD protein is significantly reduced in a cohort of 22 samples from human T-cell lymphoblastic lymphoma. Notably, the extent of such reduction varies significantly among samples and has revealed determinant for the outcome of the tumour. We demonstrate that Fas-associated protein with death domain (FADD) phosphorylation status affects protein stability, subcellular localization and non-apoptotic functions, specifically cell proliferation. Phosphorylated FADD would be more stable and preferentially localized to the cell nucleus; there, it would favour cell proliferation. We show that patients with higher levels of S194-P-FADD exhibit more proliferative tumours and that they present worse clinical characteristics and a significant enrichment to an oncogenic signature. This supports that FADD phosphorylation may serve as a predictor for T-cell lymphoblastic lymphoma aggressiveness and clinical status. In summary, we propose FADD phosphorylation as a new biomarker with prognostic value in T-cell lymphoblastic lymphoma.

The classical NLRP3 inflammasome controls FADD unconventional secretion through microvesicle shedding

Fas-associated death domain (FADD) is a key adaptor molecule involved in numerous physiological processes including cell death, proliferation, innate immunity and inflammation. Therefore, changes in FADD expression have dramatic cellular consequences. In mice and humans, FADD regulation can occur through protein secretion. However, the molecular mechanisms accounting for human FADD secretion were still unknown. Here we report that canonical, non-canonical, but not alternative, NLRP3 inflammasome activation in human monocytes/macrophages induced FADD secretion. NLRP3 inflammasome activation by the bacterial toxin nigericin led to the proinflammatory interleukin-1β (IL-1β) release and to the induction of cell death by pyroptosis. However, we showed that FADD secretion could occur in absence of increased IL-1β release and pyroptosis and, reciprocally, that IL-1β release and pyroptosis could occur in absence of FADD secretion. Especially, FADD, but not IL-1β, secretion following NLRP3 inflammasome activation required extracellular glucose. Thus, FADD secretion was an active process distinct from unspecific release of proteins during pyroptosis. This FADD secretion process required K⁺ efflux, NLRP3 sensor, ASC adaptor and CASPASE-1 molecule. Moreover, we identified FADD as a leaderless protein unconventionally secreted through microvesicle shedding, but not exosome release. Finally, we established human soluble FADD as a new marker of joint inflammation in gout and rheumatoid arthritis, two rheumatic diseases involving the NLRP3 inflammasome. Whether soluble FADD could be an actor in these diseases remains to be determined. Nevertheless, our results advance our understanding of the mechanisms contributing to the regulation of the FADD protein expression in human cells.

Foxo3a-dependent miR-633 regulates chemotherapeutic sensitivity in gastric cancer by targeting Fas-associated death domain

The development of chemotherapeutic drugs resistance such as doxorubicin (DOX) and cisplatin (DDP) is the major barrier in gastric cancer therapy. Emerging evidences reveal that microRNAs (miRNAs) contribute to chemosensitivity. In this study, we investigated the role of miR-633, an oncogenic miRNA, in gastric cancer chemoresistance. In gastric cancer tissue and cell lines, miR-633 expression was highly increased and correlated with down regulation of Fas-associated protein with death domain (FADD). Inhibition of miR-633 significantly increased FADD protein level and enhanced DOX/DDP induced apoptosis in vitro. MiR-633 antagomir administration remarkably decreased tumor growth in combination with DOX in vivo, suggesting that miR-633 targets FADD to block gastric cancer cell death. We found that the promoter region of miR-633 contained putative binding sites for forkhead box O 3 (Foxo3a), which can directly repress miR-633 transcription. In addition, we observed that DOX-induced nuclear accumulation of Foxo3a leaded to the suppression of miR-633 transcription. Together, our study revealed that miR-633/FADD axis played a significant role in the chemoresistance and Foxo3a regulated this pathway in gastric cancer. Thus, miR-633 antagomir resensitized gastric cancer cells to chemotherapy drug and had potentially therapeutic implication.

FADD at the Crossroads between Cancer and Inflammation

Initially described as an adaptor molecule for death receptor (DR)-mediated apoptosis, Fas-associated death domain (FADD) was later implicated in nonapoptotic cellular processes. During the last decade, FADD has been shown to participate and regulate most of the signalosome complexes, including necrosome, FADDosome, innateosome, and inflammasome. Given the role of these signaling complexes, FADD has emerged as a new actor in innate immunity, inflammation, and cancer development. Concomitant to these new roles, a surprising number of mechanisms deemed to regulate FADD functions have been identified, including post-translational modifications of FADD protein and FADD secretion. This review focuses on recent knowledge of the biological roles of FADD, a pleiotropic molecule having multiple partners, and its impact in cancer, innate immunity, and inflammation.

Deregulated FADD expression and phosphorylation in T-cell lymphoblastic lymphoma

In the present work, we show that T-cell lymphoblastic lymphoma cells exhibit a reduction of FADD availability in the cytoplasm, which may contribute to impaired apoptosis. In addition, we observe a reduction of FADD phosphorylation that inversely correlates with the proliferation capacity and tumor aggressiveness. The resultant balance between FADD-dependent apoptotic and non-apoptotic abilities may define the outcome of the tumor. Thus, we propose that FADD expression and phosphorylation can be reliable biomarkers with prognostic value for T-LBL stratification.

Is mitochondrial dysfunction a driving mechanism linking COPD to nonsmall cell lung carcinoma?

Chronic obstructive pulmonary disease (COPD) patients are at increased risk of developing nonsmall cell lung carcinoma, irrespective of their smoking history. Although the mechanisms behind this observation are not clear, established drivers of carcinogenesis in COPD include oxidative stress and sustained chronic inflammation. Mitochondria are critical in these two processes and recent evidence links increased oxidative stress in COPD patients to mitochondrial damage. We therefore postulate that mitochondrial damage in COPD patients leads to increased oxidative stress and chronic inflammation, thereby increasing the risk of carcinogenesis.The functional state of the mitochondrion is dependent on the balance between its biogenesis and degradation (mitophagy). Dysfunctional mitochondria are a source of oxidative stress and inflammasome activation. In COPD, there is impaired translocation of the ubiquitin-related degradation molecule Parkin following activation of the Pink1 mitophagy pathway, resulting in excessive dysfunctional mitochondria. We hypothesise that deranged pathways in mitochondrial biogenesis and mitophagy in COPD can account for the increased risk in carcinogenesis. To test this hypothesis, animal models exposed to cigarette smoke and developing emphysema and lung cancer should be developed. In the future, the use of mitochondria-based antioxidants should be studied as an adjunct with the aim of reducing the risk of COPD-associated cancer.

A multiplex platform for the identification of ovarian cancer biomarkers

Background

Currently, there are no FDA approved screening tools for detecting early stage ovarian cancer in the general population. Development of a biomarker-based assay for early detection would significantly improve the survival of ovarian cancer patients.

Methods

We used a multiplex approach to identify protein biomarkers for detecting early stage ovarian cancer. This new technology (Proseek^® Multiplex Oncology Plates) can simultaneously measure the expression of 92 proteins in serum based on a proximity extension assay. We analyzed serum samples from 81 women representing healthy, benign pathology, early, and advanced stage serous ovarian cancer patients.

Results

Principle component analysis and unsupervised hierarchical clustering separated patients into cancer versus non-cancer subgroups. Data from the Proseek^® plate for CA125 levels exhibited a strong correlation with current clinical assays for CA125 (correlation coefficient of 0.89, 95% CI 0.83, 0.93). CA125 and HE4 were present at very low levels in healthy controls and benign cases, while higher levels were found in early stage cases, with highest levels found in the advanced stage cases. Overall, significant trends were observed for 38 of the 92 proteins (p < 0.001), many of which are novel candidate serum biomarkers for ovarian cancer. The area under the ROC curve (AUC) for CA125 was 0.98 and the AUC for HE4 was 0.85 when comparing early stage ovarian cancer versus healthy controls. In total, 23 proteins had an estimated AUC of 0.7 or greater. Using a naïve Bayes classifier that combined 12 proteins, we improved the sensitivity corresponding to 95% specificity from 93 to 95% when compared to CA125 alone. Although small, a 2% increase would have a significant effect on the number of women correctly identified when screening a large population.

Conclusions

These data demonstrate that the Proseek^® technology can replicate the results established by conventional clinical assays for known biomarkers, identify new candidate biomarkers, and improve the sensitivity and specificity of CA125 alone. Additional studies using a larger cohort of patients will allow for validation of these biomarkers and lead to the development of a screening tool for detecting early stage ovarian cancer in the general population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12014-017-9169-6) contains supplementary material, which is available to authorized users.

Increased Expression of Phosphorylated FADD in Anaplastic Large Cell and Other T-Cell Lymphomas

FAS-associated protein with death domain (FADD) is a major adaptor protein involved in extrinsic apoptosis, embryogenesis, and lymphocyte homeostasis. Although abnormalities of the FADD/death receptor apoptotic pathways have been established in tumorigenesis, fewer studies have analyzed the expression and role of phosphorylated FADD (pFADD). Our identification of FADD as a lymphoma-associated autoantigen in T-cell lymphoma patients raises the possibility that pFADD, with its correlation with cell cycle, may possess role(s) in human T-cell lymphoma development. This immunohistochemical study investigated pFADD protein expression in a range of normal tissues and lymphomas, particularly T-cell lymphomas that require improved therapies. Whereas pFADD was expressed only in scattered normal T cells, it was detected at high levels in T-cell lymphomas (eg, 84% anaplastic large cell lymphoma and 65% peripheral T cell lymphomas, not otherwise specified). The increased expression of pFADD supports further study of its clinical relevance and role in lymphomagenesis, highlighting phosphorylation of FADD as a potential therapeutic target.

FAS system deregulation in T-cell lymphoblastic lymphoma

The acquisition of resistance towards FAS-mediated apoptosis may be required for tumor formation. Tumors from various histological origins exhibit FAS mutations, the most frequent being hematological malignancies. However, data regarding FAS mutations or FAS signaling alterations are still lacking in precursor T-cell lymphoblastic lymphomas (T-LBLs). The available data on acute lymphoblastic leukemia, of precursor origin as well, indicate a low frequency of FAS mutations but often report a serious reduction in FAS-mediated apoptosis as well as chemoresistance, thus suggesting the occurrence of mechanisms able to deregulate the FAS signaling pathway, different from FAS mutation. Our aim at this study was to determine whether FAS-mediated apoptotic signaling is compromised in human T-LBL samples and the mechanisms involved. This study on 26 T-LBL samples confirms that the FAS system is impaired to a wide extent in these tumors, with 57.7% of the cases presenting any alteration of the pathway. A variety of mechanisms seems to be involved in such alteration, in order of frequency the downregulation of FAS, the deregulation of other members of the pathway and the occurrence of mutations at FAS. Considering these results together, it seems plausible to think of a cumulative effect of several alterations in each T-LBL, which in turn may result in FAS/FASLG system deregulation. Since defective FAS signaling may render the T-LBL tumor cells resistant to apoptotic cell death, the correct prognosis, diagnosis and thus the success of anticancer therapy may require such an in-depth knowledge of the complete scenario of FAS-signaling alterations.

A Fas-associated via death domain promoter polymorphism (rs10898853, -16C/T) as a risk factor for papillary thyroid cancer

PURPOSE

To determine whether a Fas-associated via death domain (FADD) promoter single-nucleotide polymorphism (SNP) is associated with susceptibility to papillary thyroid cancer (PTC) and clinicopathological features of PTC.

METHODS

To identify a possible association with PTC, 94 patients with PTC and 346 healthy controls were recruited. One promoter SNP (rs10898853, -16C/T) was analyzed by direct sequencing. Multiple logistic regression models (co-dominant, dominant, recessive, and log-additive models) were applied, and odds ratios (ORs), 95% confidence intervals (CIs), and p values were calculated.

RESULTS

The genotype of the promoter SNP (rs10898853) of FADD was found to be significantly associated with PTC in the co-dominant model 2 (T/T vs. C/C; p = 0.002, OR = 2.80, 95% CI = 1.39-5.65), the recessive model (p = 0.003, OR = 2.21, 95% CI = 1.31-3.71), and the log-additive model (p = 0.002, OR = 1.71, 95% CI = 1.20-2.44). Allele frequency analysis showed that the C allele of rs10898853 was significantly associated with an increased risk of PTC (p = 0.002, OR = 1.67, 95% CI = 1.21-2.32).

CONCLUSIONS

Our results suggest that the FADD promoter polymorphism is associated with susceptibility to PTC.