EGFR phosphorylates FAM129B to promote Ras activation

Differential proteomic expression in indolent vulvar lichen sclerosus, transforming vulvar lichen sclerosus and normal vulvar tissue

Vulvar lichen sclerosus (VLS) confers approximately 3% risk of malignant transformation to vulvar squamous cell carcinoma (VSCC). We used unbiased proteomic methods to identify differentially expressed proteins in tissue of patients with VLS who developed VSCC compared to those who did not. We used laser capture microdissection- and nanoLC-tandem mass spectrometry to assess protein expression in individuals in normal vulvar tissue (NVT, n = 4), indolent VLS (no VSCC after at least 5 years follow-up, n = 5) or transforming VSCC (preceding VSCC, n = 5). Interferon-γ and antigen-presenting pathways are overexpressed in indolent and transforming VLS compared to NVT. There was differential expression of malignancy-related proteins in transforming VLS compared to indolent VLS (CAV1 overexpression, AKAP12 underexpression), particularly in the EIF2 translation pathway, which has been previously implicated in carcinogenesis. Results of this study provide additional molecular evidence supporting the concept that VLS is a risk factor for VSCC and highlights possible future biomarkers and/or therapeutic targets.

Discerning asthma endotypes through comorbidity mapping

Asthma is a heterogeneous, complex syndrome, and identifying asthma endotypes has been challenging. We hypothesize that distinct endotypes of asthma arise in disparate genetic variation and life-time environmental exposure backgrounds, and that disease comorbidity patterns serve as a surrogate for such genetic and exposure variations. Here, we computationally discover 22 distinct comorbid disease patterns among individuals with asthma (asthma comorbidity subgroups) using diagnosis records for >151 M US residents, and re-identify 11 of the 22 subgroups in the much smaller UK Biobank. GWASs to discern asthma risk loci for individuals within each subgroup and in all subgroups combined reveal 109 independent risk loci, of which 52 are replicated in multi-ancestry meta-analysis across different ethnicity subsamples in UK Biobank, US BioVU, and BioBank Japan. Fourteen loci confer asthma risk in multiple subgroups and in all subgroups combined. Importantly, another six loci confer asthma risk in only one subgroup. The strength of association between asthma and each of 44 health-related phenotypes also varies dramatically across subgroups. This work reveals subpopulations of asthma patients distinguished by comorbidity patterns, asthma risk loci, gene expression, and health-related phenotypes, and so reveals different asthma endotypes.

Inhaled nitric oxide: role in the pathophysiology of cardio-cerebrovascular and respiratory diseases

Nitric oxide (NO) is a key molecule in the biology of human life. NO is involved in the physiology of organ viability and in the pathophysiology of organ dysfunction, respectively. In this narrative review, we aimed at elucidating the mechanisms behind the role of NO in the respiratory and cardio-cerebrovascular systems, in the presence of a healthy or dysfunctional endothelium. NO is a key player in maintaining multiorgan viability with adequate organ blood perfusion. We report on its physiological endogenous production and effects in the circulation and within the lungs, as well as the pathophysiological implication of its disturbances related to NO depletion and excess. The review covers from preclinical information about endogenous NO produced by nitric oxide synthase (NOS) to the potential therapeutic role of exogenous NO (inhaled nitric oxide, iNO). Moreover, the importance of NO in several clinical conditions in critically ill patients such as hypoxemia, pulmonary hypertension, hemolysis, cerebrovascular events and ischemia-reperfusion syndrome is evaluated in preclinical and clinical settings. Accordingly, the mechanism behind the beneficial iNO treatment in hypoxemia and pulmonary hypertension is investigated. Furthermore, investigating the pathophysiology of brain injury, cardiopulmonary bypass, and red blood cell and artificial hemoglobin transfusion provides a focus on the potential role of NO as a protective molecule in multiorgan dysfunction. Finally, the preclinical toxicology of iNO and the antimicrobial role of NO-including its recent investigation on its role against the Sars-CoV2 infection during the COVID-19 pandemic-are described.

Upregulation of FAM129B protects cardiomyocytes from hypoxia/reoxygenation-induced injury by inhibiting apoptosis, oxidative stress, and inflammatory response via enhancing Nrf2/ARE activation

Family with sequence similarity 129, member B (FAM129B) has been identified as a novel cytoprotective protein that facilitates the survival of detrimentally stimulated cells. However, whether FAM129B is involved in regulating cardiomyocyte survival after myocardial ischemia-reperfusion injury is unknown. The goal of this work was to evaluate the potential role of FAM129B in regulating hypoxia/reoxygenation (H/R)-induced cardiomyocyte injury in vitro. We demonstrated that exposure to H/R markedly downregulated the expression of FAM129B in cardiomyocytes. Functional experiments revealed that the upregulation of FAM129B improved H/R-exposed cardiomyocyte viability, and ameliorated H/R-induced cardiomyocyte apoptosis, the generation of reactive oxygen species (ROS), and pro-inflammatory cytokine release. The upregulation of FAM129B significantly increased the nuclear expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), and reinforced Nrf2/antioxidant response element (ARE) activation in H/R-exposed cardiomyocytes. Moreover, FAM129B modulates Nrf2/ARE signaling in a Kelchlike ECH-associated protein 1-dependent manner. Notably, the inhibition of Nrf2 significantly blocked FAM129B-overexpression-induced cardioprotective effects in H/R-exposed cardiomyocytes. In summary, the findings of our work demonstrate that the upregulation of FAM129B ameliorates H/R-induced cardiomyocyte injury via enhancing Nrf2/ARE activation. Thus, our study indicates that FAM129B may play a role in myocardial ischemia-reperfusion injury and has the potential to be used as a cardioprotective target.

Opposing transcriptional programs of KLF5 and AR emerge during therapy for advanced prostate cancer

Endocrine therapies for prostate cancer inhibit the androgen receptor (AR) transcription factor. In most cases, AR activity resumes during therapy and drives progression to castration-resistant prostate cancer (CRPC). However, therapy can also promote lineage plasticity and select for AR-independent phenotypes that are uniformly lethal. Here, we demonstrate the stem cell transcription factor Krüppel-like factor 5 (KLF5) is low or absent in prostate cancers prior to endocrine therapy, but induced in a subset of CRPC, including CRPC displaying lineage plasticity. KLF5 and AR physically interact on chromatin and drive opposing transcriptional programs, with KLF5 promoting cellular migration, anchorage-independent growth, and basal epithelial cell phenotypes. We identify ERBB2 as a point of transcriptional convergence displaying activation by KLF5 and repression by AR. ERBB2 inhibitors preferentially block KLF5-driven oncogenic phenotypes. These findings implicate KLF5 as an oncogene that can be upregulated in CRPC to oppose AR activities and promote lineage plasticity.

Downregulation of GLUT3 impairs STYK1/NOK-mediated metabolic reprogramming and proliferation in NIH-3T3 cells

Serine threonine tyrosine kinase 1 (STYK1)/novel oncogene with kinase domain (NOK) has been demonstrated to promote cell carcinogenesis and tumorigenesis, as well as to strengthen cellular aerobic glycolysis, which is considered to be a defining hallmark of cancer. As the carriers of glucose into cells, glucose transporters (GLUTs) are important participants in cellular glucose metabolism and even tumorigenesis. However, to the best of our knowledge, the role of GLUTs in biological events caused by STYK1/NOK has not yet been reported. The present study assessed GLUT3 as a key transporter, and glucose consumption and lactate production assays revealed that downregulation of GLUT3 impaired STYK1/NOK-induced augmented glucose uptake and lactate production, and RT-qPCR and western blotting confirmed that GLUT3 knockdown attenuated the STYK1/NOK-induced increase in the expression levels of key enzymes implicated in glycolysis. Furthermore, MTT and Transwell assays demonstrated that STYK1/NOK-triggered cell proliferation and migration were also markedly decreased following knockdown of GLUT3. To the best of our knowledge, the present study is the first to demonstrate that GLUT3 serves a prominent role in STYK1/NOK-driven aerobic glycolysis and cell proliferation characteristics. These findings may provide a clue for the investigation of the oncogenic activity of STYK1/NOK and for the identification of potential tumor therapy targets associated with GLUT3.

FAM129B-dependent activation of NRF2 promotes an invasive phenotype in BRAF mutant melanoma cells

Incidence of melanoma continues to rise in the United States with ~100,000 new cases diagnosed in 2019. While the 5-year survival rate of melanoma is 99% when localized, the rate of survival drops to 22.5% when distant disease is detected. As such, an area of great interest is understanding the mechanisms that promote melanoma metastasis so that better potential therapeutic targets can be discovered. Herein, we demonstrate that activation of NRF2 by FAM129B contributes to increased metastatic potential of BRAF V600E mutant melanoma cells. Specifically, FAM129B induces NRF2 by competing for Kelch-like ECH-associated protein 1 (KEAP1) binding (the negative regulator of NRF2) via an ETGE motif. Furthermore, we show that phosphorylation of FAM129B plays a role in mediating the interaction between FAM129B and KEAP1, as the phosphorylation status of FAM129B dictates its subcellular localization. When phosphorylated, FAM129B is found primarily in the cytosol where it can bind to KEAP1, but upon inhibition of mitogen-activated protein kinase kinase activity, FAM129B is localized to the cell membrane and no longer interacts with KEAP1. In BRAF V600E mutant melanoma, the mitogen-activated protein kinase pathway leads to hyperphosphorylation of FAM129B, and therefore FAM129B localizes to the cytosol, binds KEAP1, and upregulates NRF2. Importantly, genetic modulation or pharmacological inhibition that results in a decrease in FAM129B protein level or its phosphorylation decreases migration and invasion of mutant melanoma in an NRF2-dependent manner. Overall, these data indicate that phosphorylation of FAM129B plays a significant role in driving the metastatic potential of BRAF V600E melanoma via upregulation of the NRF2 signaling pathway.

Effect of Ras-guanine nucleotide release factor 1-mediated H-Ras/ERK signaling pathway on glioma

OBJECTIVE

To investigate the function of Ras-guanine nucleotide release factor 1 (Ras-GRF1) in glioma through mediating H-Ras/ERK signaling pathway.

METHODS

Ras-GRF1, H-Ras, K-Ras and N-Ras expressions in glioma and normal brain tissues were detected via Immunohistochemistry. Glioma cells (U87 cells, U251 cells and primary human glioma cells) were transfected with Ras-GRF1 siRNA, H-Ras siRNA and/or Ras-GRF1 lentivirus activation particles. Then, the following aspects were evaluated: cell proliferation by MTT assay, clonogenic ability by the plate clone formation experiment, cell migration and invasion by Wound-healing and Transwell assays, and cell apoptosis by Annexin-V-FITC/PI staining. The protein expressions were measured by Western blotting. Subcutaneous and orthotopic mouse models of glioma were conducted to determine the role of Ras-GRF1 in glioma tumorigenesis.

RESULTS

Ras-GRF1, H-Ras, K-Ras and N-Ras expressions were upregulated in the glioma tissues, which were correlated with the WHO grade of glioma. Besides, Ras-GRF1 expression was positively related to H-Ras expression. Ras-GRF1 siRNA could reduce the expression of H-Ras and p-ERK/ERK in glioma cell. H-Ras siRNA inhibited the proliferation, clone formation, migration and invasion, and enhance the apoptosis of glioma cells, which, however, were reversed by Ras-GRF1 lentivirus activation particles. In vivo experiments also revealed that Ras-GRF1 shRNA reduced the volume and weight of the tumors in the nude mice, with down-regulations of H-Ras and p-ERK/ERK.

CONCLUSION

Ras-GRF1 was upregulated in glioma tissues and correlated with its malignancy and prognosis. Silencing Ras-GRF1, through mediating H-Ras/ERK pathway, may suppress the growth and metastasis of glioma.

Structural Insight on Functional Regulation of Human MINERVA Protein

MINERVA (melanoma invasion by ERK), also known as FAM129B, is a member of the FAM129 protein family, which is only present in vertebrates. MINERVA is involved in key signaling pathways regulating cell survival, proliferation and apoptosis and found upregulated in many types of cancer promoting invasion. However, the exact function of the protein remains elusive. X-ray crystallographic methods were implemented to determine the crystal structure of MINERVA^ΔC, lacking C-terminal flexible region. Trypsin digestion was required before crystallization to obtain diffraction-quality crystals. While the N-terminal pleckstrin homology (PH) domain exhibits the typical fold of PH domains, lipid binding assay indicates specific affinity towards phosphatidic acid and inositol 3-phosphate. A helix-rich domain that constitutes the rest of the molecule demonstrates a novel L-shaped fold that encompasses the PH domain. The overall structure of MINERVA^ΔC with binding assays and cell-based experiments suggest plasma membrane association of MINERVA and its function seem to be tightly regulated by various motifs within the C-terminal flexible region. Elucidation of MINERVA^ΔC structure presents a novel fold for an α-helix bundle domain that would provide a binding platform for interacting partners.

EGFR activates GDH1 transcription to promote glutamine metabolism through MEK/ERK/ELK1 pathway in glioblastoma

Cancer metabolism research has recently been revived and its focus expanded from glucose and the Warburg's effects on other nutrients, such as glutamine. The underlying mechanism of oncogenic alterations of glutaminolysis remains unclear. Genetic alterations of EGFR are observed in ~50% of glioblastoma (GBM) patients, and have been found to play important roles in the metabolic abnormalities of GBM. In this study, we found that glutamine metabolism was upregulated after EGFR activation in a GDH1 (glutamate dehydrogenase 1)-dependent manner. Knockdown of GDH1 significantly reduced the cell proliferation, colony formation and tumorigenesis abilities of glioblastoma cells. Furthermore, we showed that GDH1-mediated glutaminolysis was involved in EGF-promoted cell proliferation. EGFR triggered the phosphorylation of ELK1 at Ser 383 through activating MEK/ERK signaling. Phosphorylated ELK1 enriched in the promoter of GDH1 to activate the transcription of GDH1, which then promoted glutamine metabolism. In addition, EGFR activation did not accelerate glutaminolysis in ELK1 knockdown or ELK1 Ser383-mutated cells. Collectively, our findings indicate that EGFR phosphorylates ELK1 to activate GDH1 transcription and glutaminolysis through MEK/ERK pathway, providing new insight into oncogenic alterations of glutamine metabolism.

Differential Gene Expression in Erlotinib-Treated Fibroblasts

BACKGROUND

Therapies targeting the epidermal growth factor receptor (EGFR) result in a painful rash, the most common and debilitating toxicity among patients with non-small cell lung cancer (NSCLC) who take EGFR tyrosine kinase inhibitor (TKI) therapy; however, predicting the development and the severity of the rash is difficult.

OBJECTIVE

The aim of this study was to examine how erlotinib-an EGFR TKI that NSCLC patients take to stop or slow tumor growth-altered the transcriptome of dermal fibroblasts.

METHODS

Dermal fibroblasts (ATCC PCS-201-012) were seeded in cell culture flasks, grown under standard conditions, and transferred to cell culture dishes. Cells were treated once daily for 3 days with erlotinib 100 nM (n = 5), erlotinib 1 μM (n = 5), vehicle 1 μM (dimethyl sulfoxide) (n = 5), or no treatment (n = 5). Total RNA was extracted using a standard TRIzol method and hybridized using Affymetrix GeneChip Human Genome U133 Plus 2.0 arrays. Raw intensities generated from the arrays were normalized using a Robust Multiarray Average method and analyzed using analysis of variance in Limma R software. Differentially expressed genes were analyzed using Ingenuity Pathway Analysis to identify canonical or noncanonical signaling pathways enriched in this dataset.

RESULTS

We selected genes for investigation based on their potential role in wound healing (AQP3), rash development (CCL2), fibroblast activation (PALLD), cancer and cancer progression (GDF-15, SLC7A11, MMP12, and DIRAS3), and cell cycle control (CDC6). We were able to validate four of these genes by both Western blot analysis and quantitative polymerase chain reaction (MMP12, CCL2, CDC6, and SLC7A11).

DISCUSSION

If found predictive of rash in future studies using patient samples, our findings may help to identify those at risk for severe rash so that (a) the dose of EGFR TKI therapy may be adjusted; (b) additional treatments for the rash can be developed; and/or (c) precise, patient-centered interventions can be developed so that patients with cancer can better self-manage their rash and adhere to EGFR TKI treatment.

HPD degradation regulated by the TTC36-STK33-PELI1 signaling axis induces tyrosinemia and neurological damage

Decreased expression of 4-hydroxyphenylpyruvic acid dioxygenase (HPD), a key enzyme for tyrosine metabolism, is a cause of human tyrosinemia. However, the regulation of HPD expression remains largely unknown. Here, we demonstrate that molecular chaperone TTC36, which is highly expressed in liver, is associated with HPD and reduces the binding of protein kinase STK33 to HPD, thereby inhibiting STK33-mediated HPD T382 phosphorylation. The reduction of HPD T382 phosphorylation results in impaired recruitment of FHA domain-containing PELI1 and PELI1-mediated HPD polyubiquitylation and degradation. Conversely, deficiency or depletion of TTC36 results in enhanced STK33-mediated HPD T382 phosphorylation and binding of PELI1 to HPD and subsequent PELI1-mediated HPD downregulation. Ttc36^−/− mice have reduced HPD expression in the liver and exhibit tyrosinemia, damage to hippocampal neurons, and deficits of learning and memory. These findings reveal a previously unknown regulation of HPD expression and highlight the physiological significance of TTC36-STK33-PELI1-regulated HPD expression in tyrosinemia and tyrosinemia-associated neurological disorders.

Decreased expression of 4-hydroxyphenylpyruvic acid dioxygenase (HPD) has been linked to tyrosinemia, yet the mechanism underlying the regulation of HPD expression is largely unknown. Here the authors demonstrate that molecular chaperone TTC36, which is highly expressed in liver, is associated with HPD and reduces the binding of protein kinase STK33 to HPD, thereby inhibiting STK33-mediated HPD T382 phosphorylation.

FAM129B, an antioxidative protein, reduces chemosensitivity by competing with Nrf2 for Keap1 binding

BACKGROUND

The transcription factor Nrf2 is a master regulator of antioxidant response. While Nrf2 activation may counter increasing oxidative stress in aging, its activation in cancer can promote cancer progression and metastasis, and confer resistance to chemotherapy and radiotherapy. Thus, Nrf2 has been considered as a key pharmacological target. Unfortunately, there are no specific Nrf2 inhibitors for therapeutic application. Moreover, high Nrf2 activity in many tumors without Keap1 or Nrf2 mutations suggests that alternative mechanisms of Nrf2 regulation exist.

METHODS

Interaction of FAM129B with Keap1 is demonstrated by immunofluorescence, colocalization, co-immunoprecipitation and mammalian two-hybrid assay. Antioxidative function of FAM129B is analyzed by measuring ROS levels with DCF/flow cytometry, Nrf2 activation using luciferase reporter assay and determination of downstream gene expression by qPCR and wester blotting. Impact of FAM129B on in vivo chemosensitivity is examined in mice bearing breast and colon cancer xenografts. The clinical relevance of FAM129B is assessed by qPCR in breast cancer samples and data mining of publicly available databases.

FINDINGS

We have demonstrated that FAM129B in cancer promotes Nrf2 activity by reducing its ubiquitination through competition with Nrf2 for Keap1 binding via its DLG and ETGE motifs. In addition, FAM129B reduces chemosensitivity by augmenting Nrf2 antioxidative signaling and confers poor prognosis in breast and lung cancer.

INTERPRETATION

These findings demonstrate the important role of FAM129B in Nrf2 activation and antioxidative response, and identify FMA129B as a potential therapeutic target. FUND: The Chang Gung Medical Foundation (Taiwan) and the Ministry of Science and Technology (Taiwan).

Suppression of epidermal growth factor receptor-mediated β-catenin nuclear accumulation enhances the anti-tumor activity of phosphoinositide 3-kinase inhibitor in breast cancer

Phosphoinositide 3-kinase (PI3K) signaling is frequently deregulated in breast cancer and plays a critical role in tumor progression. However, resistance to PI3K inhibitors in breast cancer has emerged, which is due to the enhanced β-catenin nuclear accumulation. Until now, the mechanisms underlying PI3K inhibition-induced β-catenin nuclear accumulation remains largely unknown. In the present study, we found inhibition of PI3K with LY294002 promoted β-catenin nuclear accumulation in MCF-7 and MDA-MB-231 breast cancer cells. Combining PI3K inhibitor LY294002 with XAV-939, an inhibitor against β-catenin nuclear accumulation, produced an additive anti-proliferation effect against breast cancer cells. Subsequent experiments suggested β-catenin nuclear accumulation induced by PI3K inhibition depended on the feedback activation of epidermal growth factor receptor (EGFR) signaling pathway in breast cancer cells. Inhibition of EGFR phosphorylation with Gefitinib enhanced anti-proliferation effect of PI3K inhibitor LY294002 in MCF-7 and MDA-MB-231 cells. Taken together, our findings may elucidate a possible mechanism explaining the poor outcome of PI3K inhibitors in breast cancer treatment.

Extracellular vesicles derived from cancer-associated fibroblasts induce the migration and invasion of oral squamous cell carcinoma

As one of the most abundant constituents of the tumour microenvironment (TME), cancer-associated fibroblasts (CAF) display critical roles during tumour progression and metastasis. Multiple classes of molecules including growth factors, cytokines, proteases and extracellular matrix proteins, are produced by CAF to act as mediators of the stroma-tumour interactions. One of the main channels for this communication is associated with extracellular vesicles (EV), which are secreted particles loaded with protein and genetic information. In this study, we evaluated the effects of EV derived from CAF primary human cell lines (n = 5) on proliferation, survival, migration, and invasion of oral squamous cell carcinoma (OSCC) cells. As controls, EV from human primary-established normal oral fibroblasts (NOF, n = 5) were used. Our in vitro assays showed that CAF-EV significantly induces migration and invasion of OSCC cells and promote a disseminated pattern of HSC-3 cell invasion in the 3D organotypic assay. Furthermore, gene expression analysis of EV-treated cancer cells revealed changes in the pathways associated with tumour metabolism and up-regulation of tumour invasion genes. Our findings suggest a significant role of CAF-EV in promoting the migration and invasion of OSCC cells, which are related to the activation of cancer-related pathways.

FAM129B promoted tumor invasion and proliferation via facilitating the phosphorylation of FAK signaling and associated with adverse clinical outcome of non-small cell lung cancer patients

Background

Family with sequence similarity 129, member B (FAM129B), also called MINERVA, is upregulated and promotes tumor invasion in multiple types of cancer. However, the mechanism and clinicopathological significance of FAM129B remains unclear.

Materials and methods

Online KM-plotter tool and immunohistochemistry were used to predict the prognostic value of FAM129B expression in lung cancer tissues. Western blotting analysis, MTT, colony formation assay and matrigel invasion assay were performed after overexpressing or depleting FAM129B.

Results

In this study, using the online KM-plotter tool, we found FAM129B was correlated with adverse outcome in non-small cell lung cancer (NSCLC) patients (P<0.001). Immunohistochemistry results revealed that FAM129B showed negative or dim expression in normal lung tissues while presented positive cytoplasmic expression in both squamous cell lung carcinoma and lung adenocarcinoma. The positive ratio of FAM129B in clinical NSCLC tissue samples (77/187, 41.2%) was significantly higher than that in normal lung tissue samples (8/68, 11.8%; P<0.001). FAM129B expression associated with advanced TNM staging (P<0.001) and positive regional lymph node metastasis (P<0.001). The results of Kaplan-Meier analysis suggested that the survival time of patients with positive FAM129B expression was significantly shorter than those with negatively FAM129B expression (P<0.001). Proliferation and invasion assay revealed that FAM129B prominently facilitated tumor proliferation and invasion in NSCLC cells. Western blotting results revealed that FAM129B upregulated the expression of MMP2 and Cyclin D1 by enhancing the phosphorylation of FAK at Tyr 397 and Tyr 925. Incorporation of FAK inhibitor in the medium significantly downregulated the phosphorylation of FAK and subsequently attenuated increasing expression of MMP2 and Cyclin D1 induced by FAM129B overexpression.

Conclusion

Our results indicated that FAM129B may be a new prognosis predictor of NSCLC patients and impact tumor invasion and proliferation of NSCLC cells through promoting the activation of FAK signaling.

Regulation of Human γδ T Cells by BTN3A1 Protein Stability and ATP-Binding Cassette Transporters

Activation of human Vγ9/Vδ2 T cells by "phosphoantigens" (pAg), the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) and the endogenous isoprenoid intermediate isopentenyl pyrophosphate, requires expression of butyrophilin BTN3A molecules by presenting cells. However, the precise mechanism of activation of Vγ9/Vδ2 T cells by BTN3A molecules remains elusive. It is not clear what conformation of the three BTN3A isoforms transmits activation signals nor how externally delivered pAg accesses the cytosolic B30.2 domain of BTN3A1. To approach these problems, we studied two HLA haplo-identical HeLa cell lines, termed HeLa-L and HeLa-M, which showed marked differences in pAg-dependent stimulation of Vγ9/Vδ2 T cells. Levels of IFN-γ secretion by Vγ9/Vδ2 T cells were profoundly increased by pAg loading, or by binding of the pan-BTN3A specific agonist antibody CD277 20.1, in HeLa-M compared to HeLa-L cells. IL-2 production from a murine hybridoma T cell line expressing human Vγ9/Vδ2 T cell receptor (TCR) transgenes confirmed that the differential responsiveness to HeLa-L and HeLa-M was TCR dependent. By tissue typing, both HeLa lines were shown to be genetically identical and full-length transcripts of the three BTN3A isoforms were detected in equal abundance with no sequence variation. Expression of BTN3A and interacting molecules, such as periplakin or RhoB, did not account for the functional variation between HeLa-L and HeLa-M cells. Instead, the data implicate a checkpoint controlling BTN3A1 stability and protein trafficking, acting at an early time point in its maturation. In addition, plasma membrane profiling was used to identify proteins upregulated in HMB-PP-treated HeLa-M. ABCG2, a member of the ATP-binding cassette (ABC) transporter family was the most significant candidate, which crucially showed reduced expression in HeLa-L. Expression of a subset of ABC transporters, including ABCA1 and ABCG1, correlated with efficiency of T cell activation by cytokine secretion, although direct evidence of a functional role was not obtained by knockdown experiments. Our findings indicate a link between members of the ABC protein superfamily and the BTN3A-dependent activation of γδ T cells by endogenous and exogenous pAg.

Comprehensive Analysis of Cancer-Proteogenome to Identify Biomarkers for the Early Diagnosis and Prognosis of Cancer

During the past century, our understanding of cancer diagnosis and treatment has been based on a monogenic approach, and as a consequence our knowledge of the clinical genetic underpinnings of cancer is incomplete. Since the completion of the human genome in 2003, it has steered us into therapeutic target discovery, enabling us to mine the genome using cutting edge proteogenomics tools. A number of novel and promising cancer targets have emerged from the genome project for diagnostics, therapeutics, and prognostic markers, which are being used to monitor response to cancer treatment. The heterogeneous nature of cancer has hindered progress in understanding the underlying mechanisms that lead to abnormal cellular growth. Since, the start of The Cancer Genome Atlas (TCGA), and the International Genome consortium projects, there has been tremendous progress in genome sequencing and immense numbers of cancer genomes have been completed, and this approach has transformed our understanding of the diagnosis and treatment of different types of cancers. By employing Genomics and proteomics technologies, an immense amount of genomic data is being generated on clinical tumors, which has transformed the cancer landscape and has the potential to transform cancer diagnosis and prognosis. A complete molecular view of the cancer landscape is necessary for understanding the underlying mechanisms of cancer initiation to improve diagnosis and prognosis, which ultimately will lead to personalized treatment. Interestingly, cancer proteome analysis has also allowed us to identify biomarkers to monitor drug and radiation resistance in patients undergoing cancer treatment. Further, TCGA-funded studies have allowed for the genomic and transcriptomic characterization of targeted cancers, this analysis aiding the development of targeted therapies for highly lethal malignancy. High-throughput technologies, such as complete proteome, epigenome, protein-protein interaction, and pharmacogenomics data, are indispensable to glean into the cancer genome and proteome and these approaches have generated multidimensional universal studies of genes and proteins (OMICS) data which has the potential to facilitate precision medicine. However, due to slow progress in computational technologies, the translation of big omics data into their clinical aspects have been slow. In this review, attempts have been made to describe the role of high-throughput genomic and proteomic technologies in identifying a panel of biomarkers which could be used for the early diagnosis and prognosis of cancer.

The Glycolytic Switch in Tumors: How Many Players Are Involved?

Reprogramming of cellular metabolism is a hallmark of cancers. Cancer cells more readily use glycolysis, an inefficient metabolic pathway for energy metabolism, even when sufficient oxygen is available. This reliance on aerobic glycolysis is called the Warburg effect, and promotes tumorigenesis and malignancy progression. The mechanisms of the glycolytic shift in tumors are not fully understood. Growing evidence demonstrates that many signal molecules, including oncogenes and tumor suppressors, are involved in the process, but how oncogenic signals attenuate mitochondrial function and promote the switch to glycolysis remains unclear. Here, we summarize the current information on several main mediators and discuss their possible mechanisms for triggering the Warburg effect.

Correlated S-palmitoylation profiling of Snail-induced epithelial to mesenchymal transition

Epithelial cells form spatially-organized adhesion complexes that establish polarity gradients, regulate cell proliferation, and direct wound healing. As cells accumulate oncogenic mutations, these key tumor suppression mechanisms are disrupted, eliminating many adhesion complexes and bypassing contact inhibition. The transcription factor Snail is often expressed in malignant cancers, where it promotes transcriptional reprogramming to drive epithelial-mesenchymal transition (EMT) and establishes a more invasive state. S-Palmitoylation describes the fatty-acyl post-translational modification of cysteine residues in proteins, and is required for membrane anchoring, trafficking, localization and function of hundreds of proteins involved in cell growth, polarity, and signaling. Since Snail-expression disrupts apico-basolateral cell polarity, we asked if Snail-dependent transformation induces proteome-wide changes in S-palmitoylation. MCF10A breast cancer cells were retrovirally transduced with Snail and correlated proteome-wide changes in protein abundance and S-palmitoylation were profiled by using stable isotope labeling in cell culture with amino acid (SILAC) mass spectrometry. This analysis identified increased levels of proteins involved in migration, glycolysis, and cell junction remodeling, and decreased levels of proteins involved in cell adhesion. Overall, protein S-palmitoylation is highly correlated with protein abundance, yet for a subset of proteins, this correlation is uncoupled. These findings suggest that Snail-overexpression affects the S-palmitoylation cycle of some proteins, which may participate in cell polarity and tumor suppression.