PYGB Promoted Tumor Progression by Regulating Wnt/β-Catenin Pathway in Gastric Cancer

Population-enriched innate immune variants may identify candidate gene targets at the intersection of cancer and cardio-metabolic disease

Both cancer and cardio-metabolic disease disparities exist among specific populations in the US. For example, African Americans experience the highest rates of breast and prostate cancer mortality and the highest incidence of obesity. Native and Hispanic Americans experience the highest rates of liver cancer mortality. At the same time, Pacific Islanders have the highest death rate attributed to type 2 diabetes (T2D), and Asian Americans experience the highest incidence of non-alcoholic fatty liver disease (NAFLD) and cancers induced by infectious agents. Notably, the pathologic progression of both cancer and cardio-metabolic diseases involves innate immunity and mechanisms of inflammation. Innate immunity in individuals is established through genetic inheritance and external stimuli to respond to environmental threats and stresses such as pathogen exposure. Further, individual genomes contain characteristic genetic markers associated with one or more geographic ancestries (ethnic groups), including protective innate immune genetic programming optimized for survival in their corresponding ancestral environment(s). This perspective explores evidence related to our working hypothesis that genetic variations in innate immune genes, particularly those that are commonly found but unevenly distributed between populations, are associated with disparities between populations in both cancer and cardio-metabolic diseases. Identifying conventional and unconventional innate immune genes that fit this profile may provide critical insights into the underlying mechanisms that connect these two families of complex diseases and offer novel targets for precision-based treatment of cancer and/or cardio-metabolic disease.

Brain-Type Glycogen Phosphorylase (PYGB) in the Pathologies of Diseases: A Systematic Review

Glycogen metabolism is a form of crucial metabolic reprogramming in cells. PYGB, the brain-type glycogen phosphorylase (GP), serves as the rate-limiting enzyme of glycogen catabolism. Evidence is mounting for the association of PYGB with diverse human diseases. This review covers the advancements in PYGB research across a range of diseases, including cancer, cardiovascular diseases, metabolic diseases, nervous system diseases, and other diseases, providing a succinct overview of how PYGB functions as a critical factor in both physiological and pathological processes. We present the latest progress in PYGB in the diagnosis and treatment of various diseases and discuss the current limitations and future prospects of this novel and promising target.

RHBDD1 Promotes the Growth and Stemness Characteristics of Gastric Cancer Cells by Activating Wnt/β-catenin Signaling Pathway

BACKGROUNDS

Gastric cancer (GC) is threatening public health, with at least one million new cases reported each year. Rhomboid domain-containing protein 1 (RHBDD1) has been identified to regulate the proliferation, migration, and metastasis of cancer cells. However, the role of RHBDD1 in GC has not been elucidated.

OBJECTS

This study aimed to investigate the role of RHBDD1 on the growth, metastasis, and stemness characteristics of GC.

METHODS

RHBDD1 expression was analyzed from the TCGA databank. qRT-PCR was conducted to evaluate the transcription level of RHBDD1. Western blots were used to evaluate the protein expression of RHBDD1, CD133, CD44, Nanog, β-catenin and c-myc. Colony formation assay and transwell assay were conducted to evaluate the growth and metastasis of NCI-N87 cells, respectively. Sphere-forming assay was performed to study the stemness characteristics. The nude mice xenotransplantation model and immunohistochemistry (IHC) were performed to evaluate the growth of GC in vivo. Results: RHBDD1 expression is elevated in GC cells and clinical tissues. RHBDD1 expression is positively associated with cell proliferation and metastasis of GC cells. RHBDD1 knockdown suppresses the expression of CD133, CD44 and Nanog and attenuates sphere-forming ability. RHBDD1 activates the Wnt/β-catenin pathway via promoting the expression of β-catenin / c-myc and inducing β-catenin translocation into nuclear. RHBDD1 knockdown inhibits the growth of GC in nude mice xenotransplantation model.

CONCLUSION

RHBDD1 is highly expressed in GC, and its knockdown inhibits the growth, metastasis and stemness characteristics of GC cells through activating the Wnt/β-catenin pathway, suggesting that RHBDD1 has the potential to be a novel therapeutic target for GC treatment.

METTL3-mediated m6A methylation of PYGB facilitates pancreatic ductal adenocarcinoma progression through the activation of NF-κB signaling

Brain Type Glycogen Phosphorylase (PYGB) has been revealed to participate in the progression of multiple human cancers. Nevertheless, the clinical significance and biological function of PYGB in pancreatic ductal adenocarcinoma (PAAD) remains unclarified. This study first analyzed the expression pattern, diagnostic value, and prognostic significance of PYGB in PAAD using the TCGA database. Subsequently, western blot assessed the protein expression of genes in PAAD cells. The viability, apoptosis, migration, and invasion of PAAD cells were assessed by CCK-8, TUNEL, and Transwell assays. Finally, in vivo experiment evaluated the effect of PYGB on PAAD tumor growth and metastasis. Through our investigation, it was revealed that PYGB had extremely high expression in PAAD and predicted a worse prognosis in patients with PAAD. Besides, the aggressiveness of PAAD cells could be suppressed or enhanced by depleting or supplementing PYGB. In addition, we demonstrated that METTL3 enhanced the translation of PYGB mRNA in an m6A-YTHDF1-dependent manner. Moreover, PYGB was revealed to regulate the malignant behaviors of PAAD cells by the mediation of the NF-κB signaling. Finally, PYGB depletion suppressed the growth and distant metastasis of PAAD in vivo. To conclude, our results indicated that METTL3-mediated m6A modification of PYGB exerted the tumor-promotive effect on PAAD through NF-κB signaling, suggesting PYGB is a potential therapeutic target in PAAD.

Identification of a necroptosis-related gene signature as a novel prognostic biomarker of cholangiocarcinoma

Background

Cholangiocarcinoma (CHOL) is the most prevalent type of malignancy and the second most common form of primary liver cancer, resulting in high rates of morbidity and mortality. Necroptosis is a type of regulated cell death that appears to be involved in the regulation of several aspects of cancer biology, including tumorigenesis, metastasis, and cancer immunity. This study aimed to construct a necroptosis-related gene (NRG) signature to investigate the prognosis of CHOL patients using an integrated bioinformatics analysis.

Methods

CHOL patient data were acquired from the Gene Expression Omnibus (GEO) (GSE89748, GSE107943) and The Cancer Genome Atlas (TCGA) databases, with NRGs data from the necroptosis pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Univariate and multivariate regression analyses were performed to establish the NRG signatures. Kaplan-Meier (KM) curves were used to evaluate the prognosis of patients with CHOL. Functional enrichment analysis was performed to identify key NRG-associated biological signaling pathways. We also applied integrative multi-omics analysis to the high- and low-risk score groups. Spearman's rank correlation was used to clarify the relationship between the NRG signature and immune infiltration.

Results

65 differentially expressed (DE) NRGs were screened, five of which were selected to establish the prognostic signature of NRG_S based on multivariate Cox regression analysis. We observed that low-risk patients survived significantly longer than high-risk patients. We found that patients with high-risk scores experienced higher immune cell infiltration, drug resistance, and more somatic mutations than patients with low-risk scores. We further found that sensitivities to GW843682X, mitomycin C, rapamycin, and S-trityl-L-cysteine were significantly higher in the low-risk group than in the high-risk group. Finally, we validated the expression of five NRGs in CHOL tissues using the TCGA database, HPA database and our clinical data.

Conclusion

These findings demonstrate that the five-NRG prognostic signature for CHOL patients is reasonably accurate and valid, and it may prove to be of considerable value for the treatment and prognosis of CHOL patients in the future.

PYGL-mediated glucose metabolism reprogramming promotes EMT phenotype and metastasis of pancreatic cancer

Epithelial-mesenchymal transition (EMT) is closely associated with tumor invasion and metastasis. However, key regulators of EMT in pancreatic ductal adenocarcinoma (PDAC) need to be further studied. Bioinformatics analyses of pancreatic cancer public datasets showed that glycogen phosphorylase L (PYGL) expression is elevated in quasimesenchymal PDAC (QM-PDAC) and positively associated with EMT. In vitro cellular experiments further confirm PYGL as a crucial EMT regulator in PDAC cells. Functionally, PYGL overexpression promotes cell migration and invasion in vitro and facilitates liver metastasis in vivo, while PYGL knockdown has opposite effects. Mechanically, hypoxia induces PYGL expression in a hypoxia inducible factor 1α (HIF1α)-dependent manner and promotes glycogen accumulation. Elevated PYGL mobilizes accumulated glycogen to fuel glycolysis via its activity as a glycogen phosphorylase, thus inducing the EMT process, which could be suppressed by the glycolysis inhibitor 2-deoxy-D-glucose (2-DG). Clinically, PYGL expression is upregulated in PDAC and correlates with its malignant features and poor prognosis. Collectively, the data from our study reveal that the hypoxia/PYGL/glycolysis-induced EMT promotes PDAC metastasis, which establishes the rational for targeting hypoxia/PYGL/glycolysis/EMT signaling pathway against PDAC.

A Proteomic Platform Unveils the Brain Glycogen Phosphorylase as a Potential Therapeutic Target for Glioblastoma Multiforme

In the last few years, several efforts have been made to identify original strategies against glioblastoma multiforme (GBM): this requires a more detailed investigation of the molecular mechanism of GBM so that novel targets can be identified for new possible therapeutic agents. Here, using a combined biochemical and proteomic approach, we evaluated the ability of a blood–brain barrier-permeable 2,3-benzodiazepin-4-one, called 1g, to interfere with the activity and the expression of brain glycogen phosphorylase (PYGB) on U87MG cell line in parallel with the capability of this compound to inhibit the cell growth and cycle. Thus, our results highlighted PYGB as a potential therapeutic target in GBM prompting 1g as a capable anticancer drug thanks to its ability to negatively modulate the uptake and metabolism of glucose, the so-called “Warburg effect”, whose increase is considered a common feature of cancer cells in respect of their normal counterparts.

Liver glycogen phosphorylase is upregulated in glioblastoma and provides a metabolic vulnerability to high dose radiation

Channelling of glucose via glycogen, known as the glycogen shunt, may play an important role in the metabolism of brain tumours, especially in hypoxic conditions. We aimed to dissect the role of glycogen degradation in glioblastoma (GBM) response to ionising radiation (IR). Knockdown of the glycogen phosphorylase liver isoform (PYGL), but not the brain isoform (PYGB), decreased clonogenic growth and survival of GBM cell lines and sensitised them to IR doses of 10-12 Gy. Two to five days after IR exposure of PYGL knockdown GBM cells, mitotic catastrophy and a giant multinucleated cell morphology with senescence-like phenotype developed. The basal levels of the lysosomal enzyme alpha-acid glucosidase (GAA), essential for autolysosomal glycogen degradation, and the lipidated forms of gamma-aminobutyric acid receptor-associated protein-like (GABARAPL1 and GABARAPL2) increased in shPYGL U87MG cells, suggesting a compensatory mechanism of glycogen degradation. In response to IR, dysregulation of autophagy was shown by accumulation of the p62 and the lipidated form of GABARAPL1 and GABARAPL2 in shPYGL U87MG cells. IR increased the mitochondrial mass and the colocalisation of mitochondria with lysosomes in shPYGL cells, thereby indicating reduced mitophagy. These changes coincided with increased phosphorylation of AMP-activated protein kinase and acetyl-CoA carboxylase 2, slower ATP generation in response to glucose loading and progressive loss of oxidative phosphorylation. The resulting metabolic deficiencies affected the availability of ATP required for mitosis, resulting in the mitotic catastrophy observed in shPYGL cells following IR. PYGL mRNA and protein levels were higher in human GBM than in normal human brain tissues and high PYGL mRNA expression in GBM correlated with poor patient survival. In conclusion, we show a major new role for glycogen metabolism in GBM cancer. Inhibition of glycogen degradation sensitises GBM cells to high-dose IR indicating that PYGL is a potential novel target for the treatment of GBMs.

Analysis of the expression, function and signaling of glycogen phosphorylase isoforms in hepatocellular carcinoma

Glycogen phosphorylase (GP) is an essential enzyme for glycolysis via the glycogen degradation pathway. It consists of three isoforms: PYGB (brain form), PYGL (liver form) and PYGM (muscle form). Although the abnormal expression of GP is associated with a variety of tumors, its relationship with hepatocellular carcinoma (HCC) and whether it can be used as a prognostic marker of HCC remains unclear. In the present study, the expression levels of PYGB, PYGL and PYGM were analyzed. It was found that the expression levels of PYGB in tumor tissues were higher than those in normal tissues, particularly in HCC. The high expression of PYGB (hazard ratios=1.801; 95% confidence interval: 1.266-2.562) could predict the poor prognosis of HCC patients but not PYGL and PYGM. Inhibition of PYGB with GP inhibitor CP91149 significantly suppressed the HCC cell proliferation in the HCC cell model. In addition, combination treatment with sorafenib, a standard treatment for HCC, showed a great inhibition on tumor growth and angiogenesis. These findings suggested that PYGB may be used as a therapeutic and prognostic indicator for HCC.

Identification of shared and disease-specific host gene-microbiome associations across human diseases using multi-omic integration

While gut microbiome and host gene regulation independently contribute to gastrointestinal disorders, it is unclear how the two may interact to influence host pathophysiology. Here we developed a machine learning-based framework to jointly analyse paired host transcriptomic (n = 208) and gut microbiome (n = 208) profiles from colonic mucosal samples of patients with colorectal cancer, inflammatory bowel disease and irritable bowel syndrome. We identified associations between gut microbes and host genes that depict shared as well as disease-specific patterns. We found that a common set of host genes and pathways implicated in gastrointestinal inflammation, gut barrier protection and energy metabolism are associated with disease-specific gut microbes. Additionally, we also found that mucosal gut microbes that have been implicated in all three diseases, such as Streptococcus, are associated with different host pathways in each disease, suggesting that similar microbes can affect host pathophysiology in a disease-specific manner through regulation of different host genes. Our framework can be applied to other diseases for the identification of host gene-microbiome associations that may influence disease outcomes.

Formation and physicochemical properties of glycogen phosphorylase in complex with a cationic polyelectrolyte

The accumulation of rabbit muscle glycogen phosphorylase b (RMGPb) in electrostatic complexes with the cationic polyelectrolyte poly 2-(dimethylamino) ethyl methacrylate in its quenched form (QPDMAEMA) was studied in two buffer solutions. In the N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES) buffer, large complexes of RMGPb-QPDMAEMA were formed which adopted smaller sizes as QPDMAEMA concentration increased. However, in N-(2-hydroxyethyl)piperazine-N'-(2-ethanesulfonic acid) (HEPES) buffer, the hydrodynamic radius of the formed complexes gradually increased as the polymer concentration increased. Zeta potential measurements (ζ_p) showed that RMGPb significantly changed the ζ_p of the QPDMAEMA aggregates. Fluorescence studies showed that the interaction between RMGPb and QPDMAEAMA was enhanced as polymer concentration increased. Specifically, 8-anilinonaphthalene-1-sulfonic acid (ANS) fluorescence indicated that in the BES buffer the aggregates became denser as more QPDMAEMA was added, while in the HEPES buffer the density of the formed structures decreased. RMGPb's secondary structure was examined by Attenuated Total Reflection - Fourier Transform Infrared (ATR-FTIR) and Circular Dichroism (CD) showing that QPDMAEMA interaction with RMGPb does not induce any changes to the secondary structure of the enzyme. These observations suggest that cationic polyelectrolytes may be utilized for the formulation of RMGPb in multifunctional nanostructures and be further exploited in innovative biotechnology applications and bioinspired materials development.

Identification of a glycolysis-related gene signature for survival prediction of ovarian cancer patients

Background

Ovarian cancer (OV) is deemed the most lethal gynecological cancer in women. The aim of this study was to construct an effective gene prognostic model for predicting overall survival (OS) in patients with OV.

Methods

The expression profiles of glycolysis‐related genes (GRGs) and clinical data of patients with OV were extracted from The Cancer Genome Atlas (TCGA) database. Univariate, multivariate, and least absolute shrinkage and selection operator Cox regression analyses were conducted, and a prognostic signature based on GRGs was constructed. The predictive ability of the signature was analyzed using training and test sets.

Results

A gene risk signature based on nine GRGs (ISG20, CITED2, PYGB, IRS2, ANGPTL4, TGFBI, LHX9, PC, and DDIT4) was identified to predict the survival outcome of patients with OV. The signature showed a good prognostic ability for OV, particularly high‐grade OV, in the TCGA dataset, with areas under the curve (AUC) of 0.709 and 0.762 for 3‐ and 5‐year survival, respectively. Similar results were found in the test sets, and the AUCs of 3‐, 5‐year OS were 0.714 and 0.772 in the combined test set. And our signature was an independent prognostic factor. Moreover, a nomogram combining the prediction model and clinical factors was developed.

Conclusion

Our study established a nine‐GRG risk model and nomogram to better predict OS in patients with OV. The risk model represents a promising and independent prognostic predictor for patients with OV. Moreover, our study on GRGs could offer guidance for the elucidation of underlying mechanisms in future studies.

Identification and validation of a novel glycolysis-related gene signature for predicting the prognosis in ovarian cancer

Background

Ovarian cancer (OC) is the most lethal gynaecological tumor. Changes in glycolysis have been proven to play an important role in OC progression. We aimed to identify a novel glycolysis-related gene signature to better predict the prognosis of patients with OC.

Methods

mRNA and clinical data were obtained from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Genotype Tissue Expression (GTEx) database. The “limma” R package was used to identify glycolysis-related differentially expressed genes (DEGs). Then, a multivariate Cox proportional regression model and survival analysis were used to develop a glycolysis-related gene signature. Furthermore, the TCGA training set was divided into two internal test sets for validation, while the ICGC dataset was used as an external test set. A nomogram was constructed in the training set, and the relative proportions of 22 types of tumor-infiltrating immune cells were evaluated using the “CIBERSORT” R package. The enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were determined by single-sample gene set enrichment analysis (ssGSEA) with the “GSVA” R package. Finally, the expression and function of the unreported signature genes ISG20 and SEH1L were explored using immunohistochemistry, western blotting, qRT-PCR, proliferation, migration, invasion and xenograft tumor assays.

Results

A five-gene signature comprising ANGPTL4, PYGB, ISG20, SEH1L and IRS2 was constructed. This signature could predict prognosis independent of clinical factors. A nomogram incorporating the signature and three clinical features was constructed, and the calibration plot suggested that the nomogram could accurately predict the survival rate. According to ssGSEA, the signature was associated with KEGG pathways related to axon guidance, mTOR signalling, tight junctions, etc. The proportions of tumor-infiltrating immune cells differed significantly between the high-risk group and the low-risk group. The expression levels of ISG20 and SEH1L were lower in tumor tissues than in normal tissues. Overexpression of ISG20 or SEH1L suppressed the proliferation, migration and invasion of Caov3 cells in vitro and the growth of xenograft tumors in vivo.

Conclusion

Five glycolysis-related genes were identified and incorporated into a novel risk signature that can effectively assess the prognosis and guide the treatment of OC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02045-0.