The rapid proliferation of cancer cells and dysregulated vasculature within the tumor leads to limited nutrient accessibility. Cancer cells often rewire their metabolic pathways for adaption to nutrient stress, and the underlying mechanism remains largely unknown. Glutamate dehydrogenase 1 (GDH1) is a key enzyme in glutaminolysis that converts glutamate to α-ketoglutarate (α-KG). Here, we show that, under low glucose, GDH1 is phosphorylated at serine (S) 384 and interacts with RelA and IKKβ. GDH1-produced α-KG directly binds to and activates IKKβ and nuclear factor κB (NF-κB) signaling, which promotes glucose uptake and tumor cell survival by upregulating GLUT1, thereby accelerating gliomagenesis. In addition, GDH1 S384 phosphorylation correlates with the malignancy and prognosis of human glioblastoma. Our finding reveals a unique role of α-KG to directly regulate signal pathway, uncovers a distinct mechanism of metabolite-mediated NF-κB activation, and also establishes the critical role of α-KG-activated NF-κB in brain tumor development.

6-Phosphogluconate dehydrogenase (6PGD) is a key enzyme that converts 6-phosphogluconate into ribulose-5-phosphate with NADP+ as cofactor in the pentose phosphate pathway (PPP). 6PGD is commonly upregulated and plays important roles in many human cancers, while the mechanism underlying such roles of 6PGD remains elusive. Here we show that upon EGFR activation, 6PGD is phosphorylated at tyrosine (Y) 481 by Src family kinase Fyn. This phosphorylation enhances 6PGD activity by increasing its binding affinity to NADP+ and therefore activates the PPP for NADPH and ribose-5-phosphate, which consequently detoxifies intracellular reactive oxygen species (ROS) and accelerates DNA synthesis. Abrogating 6PGD Y481 phosphorylation (pY481) dramatically attenuates EGF-promoted glioma cell proliferation, tumor growth and resistance to ionizing radiation. In addition, 6PGD pY481 is associated with Fyn expression, the malignancy and prognosis of human glioblastoma. These findings establish a critical role of Fyn-dependent 6PGD phosphorylation in EGF-promoted tumor growth and radiation resistance.

Recent studies have revealed that neurons can promote glioma growth through activity-dependent secretion of neurotrophins, especially neuroligin-3. It has therefore been suggested that blocking neuron-derived neurotrophins may serve as a therapeutic intervention for gliomas. Carbonic anhydrase-related proteins 11 and 10 (CA11 and CA10) are secreted synaptic proteins which function as neurexin ligands, and the gene-encoding CA11 is part of a gene signature associated with radiotherapy and prognosis in gliomas. We therefore hypothesized that CA11/CA10 might participate in the neuronal activity-dependent regulation of glioma growth. In this study, we report that CA11 secreted by depolarized cultured neurons within conditioned medium (CM) inhibited the growth of glioma cell lines. CM from depolarized neurons inhibited CA11 expression in glioma cell lines via the Akt signaling pathway. Consistently, CA11 expression was also reduced in clinical glioma samples and negatively associated with high histological grade. Low CA11 expression of gliomas was associated with short survival in four independent datasets [repository of brain neoplasia data (REMBRANDT), The Cancer Genome Atlas (TCGA) lower grade glioma (LGG), GSE4271, and GSE42669]. CA11 knockdown promoted cell growth, clone formation, and migration; inhibited apoptosis; and increased tumor size in xenografted nude mice. Similarly, CA10 and CA10 secreted by depolarized cultured neurons also inhibited the growth of glioma cell lines. Low CA10 expression was associated with short survival in REMBRANDT, TCGA LGG, and GEO GSE4271 datasets. Our results suggest that CA11 and CA10 negatively regulate neuronal activity-dependent glioma growth and inhibit glioma aggression. Thus, CA11/CA10 may represent a potential therapeutic target for the treatment of gliomas.

Pyruvate kinase M2 isoform (PKM2) catalyzes the last step of glycolysis and plays an important role in tumor cell proliferation. Recent studies have reported that PKM2 also regulates apoptosis. However, the mechanisms underlying such a role of PKM2 remain elusive. Here we show that PKM2 translocates to mitochondria under oxidative stress. In the mitochondria, PKM2 interacts with and phosphorylates Bcl2 at threonine (T) 69. This phosphorylation prevents the binding of Cul3-based E3 ligase to Bcl2 and subsequent degradation of Bcl2. A chaperone protein, HSP90α1, is required for this function of PKM2. HSP90α1's ATPase activity launches a conformational change of PKM2 and facilitates interaction between PKM2 and Bcl2. Replacement of wild-type Bcl2 with phosphorylation-deficient Bcl2 T69A mutant sensitizes glioma cells to oxidative stress-induced apoptosis and impairs brain tumor formation in an orthotopic xenograft model. Notably, a peptide that is composed of the amino acid residues from 389 to 405 of PKM2, through which PKM2 binds to Bcl2, disrupts PKM2-Bcl2 interaction, promotes Bcl2 degradation and impairs brain tumor growth. In addition, levels of Bcl2 T69 phosphorylation, conformation-altered PKM2 and Bcl2 protein correlate with one another in specimens of human glioblastoma patients. Moreover, levels of Bcl2 T69 phosphorylation and conformation-altered PKM2 correlate with both grades and prognosis of glioma malignancy. Our findings uncover a novel mechanism through which mitochondrial PKM2 phosphorylates Bcl2 and inhibits apoptosis directly, highlight the essential role of PKM2 in ROS adaptation of cancer cells, and implicate HSP90-PKM2-Bcl2 axis as a potential target for therapeutic intervention in glioblastoma.

Many types of human tumour cells overexpress the dual-specificity phosphatase Cdc25A. Cdc25A dephosphorylates cyclin-dependent kinase and regulates the cell cycle, but other substrates of Cdc25A and their relevant cellular functions have yet to be identified. We demonstrate here that EGFR activation results in c-Src-mediated Cdc25A phosphorylation at Y59, which interacts with nuclear pyruvate kinase M2 (PKM2). Cdc25A dephosphorylates PKM2 at S37, and promotes PKM2-dependent β-catenin transactivation and c-Myc-upregulated expression of the glycolytic genes GLUT1, PKM2 and LDHA, and of CDC25A; thus, Cdc25A upregulates itself in a positive feedback loop. Cdc25A-mediated PKM2 dephosphorylation promotes the Warburg effect, cell proliferation and brain tumorigenesis. In addition, we identify positive correlations among Cdc25A Y59 phosphorylation, Cdc25A and PKM2 in human glioblastoma specimens. Furthermore, levels of Cdc25A Y59 phosphorylation correlate with grades of glioma malignancy and prognosis. These findings reveal an instrumental function of Cdc25A in controlling cell metabolism, which is essential for EGFR-promoted tumorigenesis.

DNA repair confers the resistance of tumor cells to DNA-damaging anticancer therapies, while how reprogrammed metabolism in tumor cells contributes to such process remains poorly understood. Pyruvate kinase M2 isoform (PKM2) catalyzes the conversion of phosphoenolpyruvate to pyruvate and regulates the last rate-limiting step of glycolysis. Here it is shown that the glycolytic metabolite pyruvate enhances DNA damage repair by facilitating chromatin loading of γH2AX, thereby promoting the radiation resistance of glioma cells. Mechanistically, PKM2 is phosphorylated at serine (S) 222 upon DNA damage and interacts with FACT complex, a histone chaperone comprising SPT16 and SSRP1 subunit. The pyruvate produced by PKM2 directly binds to SSRP1, which increases the association of FACT complex with γH2AX and subsequently facilitates FACT-mediated chromatin loading of γH2AX, ultimately promoting DNA repair and tumor cell survival. Intriguingly, the supplementation of exogenous pyruvate can also sufficiently enhance FACT-mediated chromatin loading of γH2AX and promotes tumor cell survival upon DNA damage. The levels of PKM2 S222 phosphorylation correlate with the malignancy and prognosis of human glioblastoma. The finding demonstrates a novel mechanism by which PKM2-produced pyruvate promotes DNA repair by regulating γH2AX loading to chromatin and establishes a critical role of this mechanism in glioblastoma radiation resistance.

Recent breakthroughs in therapies with immune checkpoint inhibitors (ICIs) have revolutionized the treatment of lung cancer. However, only 15-25% of patients respond to the ICIs therapy, and methods to identify those responsive patients are currently a hot research topic. PD-L1 expression measured on tumor tissues using immunohistochemistry (IHC) was approved as one of the companion diagnostic methods, but it is invasive and cannot be used to monitor dynamic changes in PD-L1 expression during treatments.

Circulating extracellular vesicles (EVs) were recognized as a promising source of diagnostic biomarker. However, there are limited studies published in this area, partly due to the limited number of detection platforms capable of detecting extracellular vesicles. In this study, extracellular vesicle immunoassays were developed using the Single Molecule array technology (SiMoa) and their clinical applications to cancer diagnosis were evaluated. Two extracellular vesicle detection assays, CD9-CD63 and Epcam-CD63, were designed to detect universal extracellular vesicles and tumour-derived extracellular vesicles, respectively. Our results show that CD9-CD63 and Epcam-CD63 SiMoa assays specifically detect extracellular vesicles but not free proteins with high sensitivities. The Epcam-CD63 levels detected in cancer cell culture media were consistent with levels of Epcam-expressing EVs isolated from the same cancer cell lines and detected by Western blot. Furthermore, the assays distinguish cancerous from non-cancerous plasma samples. The highest CD9-CD63 and Epcam-CD63 signals were observed in colorectal cancer patients comparing to healthy and benign controls. Both assays showed superior diagnostic performance for colorectal cancer. In addition, our results show that CD9-CD63 detection is an independent prognosis factor for both progression free survival and overall survival, while Epcam-CD63 detectionis an independent prognosis factor for OS.

Glioma is one of the most common primary brain tumors with poor prognosis. Although radiotherapy is an important treatment method for gliomas, the efficacy is still limited by the high occurrence of radioresistance and the underlying molecular mechanism is unclear. Here, we performed a data mining work based on four glioma expression datasets. These datasets were classified into training set and validation set. Radiotherapy-induced differential expressed genes and prognosis-associated genes were screened using different classifiers. The Kaplan-Meier curves along with the two-sided Log Rank (Mantel-Cox) test were used to evaluate overall survival. We found the gene expression profiles of gliomas between those patients received radiotherapy and those patients without received radiotherapy were quite different. A 20-gene signature was identified, which was associated with radiotherapy.Furthermore, a novel 5-gene signature (HOXC10, LOC101928747, CYB561D2, RPL36A and RPS4XP2) as an independent predictor of glioma patients' prognosis was further derived from the 20-gene signature. These findings provided a new insight into the molecular mechanism of radioresistance in gliomas. The 5-gene signature might represent therapeutic target for gliomas.

Macrophages are a dominant leukocyte population in the tumor microenvironment and actively promote cancer progression. However, the molecular mechanism underlying the role of macrophages remains poorly understood. Here we show that polarized M2 macrophages enhance 3-phosphoinositide-dependent protein kinase 1 (PDPK1)-mediated phosphoglycerate kinase 1 (PGK1) threonine (T) 243 phosphorylation in tumor cells by secreting interleukin-6 (IL-6). This phosphorylation facilitates a PGK1-catalyzed reaction toward glycolysis by altering substrate affinity. Inhibition of PGK1 T243 phosphorylation or PDPK1 in tumor cells or neutralization of macrophage-derived IL-6 abrogates macrophage-promoted glycolysis, proliferation, and tumorigenesis. In addition, PGK1 T243 phosphorylation correlates with PDPK1 activation, IL-6 expression, and macrophage infiltration in human glioblastoma multiforme (GBM). Moreover, PGK1 T243 phosphorylation also correlates with malignance and prognosis of human GBM. Our findings demonstrate a novel mechanism of macrophage-promoted tumor growth by regulating tumor cell metabolism, implicating the therapeutic potential to disrupt the connection between macrophages and tumor cells by inhibiting PGK1 phosphorylation.

Determining the mechanism of treatment failure of VEGF signaling inhibitors for malignant glioma patients would provide insight into approaches to overcome therapeutic resistance. In this study, we demonstrate that human glioblastoma tumors failing bevacizumab have an increase in the mean percentage of p-STAT3-expressing cells compared to samples taken from patients failing non-antiangiogenic therapy containing regimens. Likewise, in murine xenograft models of glioblastoma, the mean percentage of p-STAT3-expressing cells in the gliomas resistant to antiangiogenic therapy was markedly elevated relative to controls. Administration of the JAK/STAT3 inhibitor AZD1480 alone and in combination with cediranib reduced tumor hypoxia and the infiltration of VEGF inhibitor-induced p-STAT3 macrophages. Thus, the combination of AZD1480 with cediranib markedly reduced tumor volume, and microvascular density, indicating that up regulation of the STAT3 pathway can mediate resistance to antiangiogenic therapy and combinational approaches may delay or overcome resistance.

Tumor-specific pyruvate kinase M2 (PKM2) is essential for the Warburg effect. In addition to its well-established role in aerobic glycolysis, PKM2 directly regulates gene transcription. However, the mechanism underlying this nonmetabolic function of PKM2 remains elusive. We show here that PKM2 directly binds to histone H3 and phosphorylates histone H3 at T11 upon EGF receptor activation. This phosphorylation is required for the dissociation of HDAC3 from the CCND1 and MYC promoter regions and subsequent acetylation of histone H3 at K9. PKM2-dependent histone H3 modifications are instrumental in EGF-induced expression of cyclin D1 and c-Myc, tumor cell proliferation, cell-cycle progression, and brain tumorigenesis. In addition, levels of histone H3 T11 phosphorylation correlate with nuclear PKM2 expression levels, glioma malignancy grades, and prognosis. These findings highlight the role of PKM2 as a protein kinase in its nonmetabolic functions of histone modification, which is essential for its epigenetic regulation of gene expression and tumorigenesis.

To study the kinetic profile and clinicopathological implications of squamous cell carcinoma antigen (SCC-Ag) in cervical cancer patients who underwent surgery by a self-developed SCC-Ag single molecule assay (Simoa) prototype immunoassay.

Fine tuned balance of reactive oxygen species (ROS) is essential for tumor cells and tumor cells use immune checkpoints to evade attack form immunity system. However, it's unclear whether there is any crosstalk between these two pathways. CYB561D2, an antioxidant protein, is part of 5-gene prognosis signature in gliomas and its involvement in gliomas is unknown. Here, we aim to provide a detailed characterization of CYB561D2 in gliomas.

The clinical prognosis of malignant gliomas is poor and PCDH9 down-regulation is strongly associated with its poor prognosis. But the mechanism of PCDH9 down-regulation is unknown. Abnormal miRNAs profiles regulate tumor phenotypes through inhibiting their target genes and miRNAs could inhibit target genes more efficiently by binding to both the promoter and 3'UTR of target genes. In this study, to search the dual inhibitory miRNAs which suppress PCDH9 expression in gliomas, we performed an integrative analysis of databases including miRDB, TargetScan, microPIR and miRCancer. We identified three candidate miRNAs which were predicted to bind both the promoter and 3'UTR of PCDH9 and up-regulated in gliomas. Then, we validated miR-215-5p up-regulation and PCDH9 down-regulation in glioma samples and demonstrated that miR-215-5p could inhibit the mRNA and protein levels of PCDH9 in glioma cell lines by targeting its promoter and 3' UTR at the same time. Moreover, miR-215-5p could increase glioma cell proliferation, clone formation, in-vitro migration and reduce apoptosis via inhibiting PCDH9 expression. Our study provides evidence for a novel dual inhibition of PCDH9 by miR-215-5p in gliomas and suggests that miR-215-5p might be a therapeutic target for the treatment of gliomas.

Antiangiogenic therapy is commonly being used for the treatment of glioblastoma. However, the benefits of angiogenesis inhibitors are typically transient and resistance often develops. Determining the mechanism of treatment failure of the VEGF monoclonal antibody bevacizumab for malignant glioma would provide insight into approaches to overcome therapeutic resistance.

Hepatocellular carcinoma (HCC) is one of the most common and lethal malignancies. Early detection of HCC could largely reduce mortalities. Ultrasonography (US) and serum Alpha Fetoprotein (AFP) test are the screening methods that are most frequently applied to high-risk populations. Due to the poor performance of AFP testing, and the highly operator-dependent nature of US, a biomarker for HCC early diagnosis is highly sought after. We developed a method for HCC screening using a 22-gene expression signature.

Inflammasome contributes to ischemic brain injury by inducing pyroptosis and inflammation. The aim of this study is to unravel the mechanism of long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3)-mediated regulation of absent in melanoma 2 (AIM2) inflammasome during cerebral ischemia/reperfusion (I/R).

Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the rate-limiting step in tryptophan catabolism along the kynurenine (Kyn) pathway and exerts immunosuppressive properties mainly via activation of transcription factor aryl hydrocarbon receptor (AhR) pathway. IDO1 induces NK cells dysfunction via downregulation of the activating receptor NKG2D on NK cells, but whether and how it affects the expression of NKG2D Ligand (NKG2DL) on tumor cells remains unclear. Since a disintegrin and metalloprotease 10 (ADAM10) plays a potential role in the shedding of NKG2DL and the releasing of soluble NKG2DL (sNKG2DL), we investigated how IDO1 modulates the expression of NKG2DL via ADAM10 in non-small cell lung cancer (NSCLC). We found that IDO1 expression was negatively correlated with NKG2DL expression while positively correlated with ADAM10 expression with human lung cancer brain metastasis tissue, NSCLC cells and LLC tumor-bearing mice. IDO1 could regulate ADAM10 expression via IDO1-Kyn-AhR signaling pathway and subsequently regulate NKG2DL expression. IDO1 deficiency led to retarded tumor growth and improved NK cells function in NSCLC mice. IDO1 inhibitors improved NK cells function in vitro and in vivo. The combo of IDO1 inhibitor and NK cells exhibited more therapeutic efficacy than either of the single IDO1 inhibitor or NK cells treatment.