Reduction of AZGP1 predicts poor prognosis in esophageal squamous cell carcinoma patients in Northern China

Zinc-alpha-2-glycoprotein overexpression and maintaining anti-apoptotic function in oral squamous cell carcinoma

OBJECTIVE

Overexpression of zinc-alpha-2-glycoprotein (ZAG) can be induced by various factors and has potential to be a biomarker in certain malignancies. However, in oral squamous cell carcinoma (OSCC), the risks and effects associated with ZAG overexpression are still poorly known. Here, we investigated the effect of HPV16 oncogenes and arecoline on the expression levels of ZAG and the possible effects of ZAG in OSCC cell lines.

DESIGN

The level of ZAG expression was determined in protein extracted from exfoliated buccal cells from cancer-free control individuals and oral lesion cells from OSCC. Oral cell lines expressing HPV16E6/E7, and treated with arecoline were prepared to investigate ZAG expression. The effects of ZAG on cell biological activity and its targeting of UCP1 were determined in ZAG-overexpressing and ZAG-knockdown cells.

RESULTS

The expression of ZAG protein was significantly increased in oral lesion cells from OSCC relative to controls. Notably, the expression level of ZAG in OSCC positive for HPV, betel-quid chewing, and combination of both factors, was slightly higher than in cancer-free controls. ZAG expression was upregulated in oral cells treated with HPV16 oncoproteins E6 and/or E7, and treatment with arecoline (25 μg/ml). Interestingly, ZAG overexpression significantly increased UCP1 and decreased apoptosis, whereas decreased UCP1 and increased apoptosis were found in ZAG-knockdown cells. The mRNA expression levels of TP53, STAT3, BCL2, and NFKB1 corresponded to observed anti-apoptosis function.

CONCLUSIONS

HPV oncoproteins and high doses of arecoline are risk factors for an overexpressed ZAG protein that has an anti-apoptotic function in OSCC.

AZGP1 deficiency promotes angiogenesis in prostate cancer

BACKGROUND

Loss of AZGP1 expression is a biomarker associated with progression to castration resistance, development of metastasis, and poor disease-specific survival in prostate cancer. However, high expression of AZGP1 cells in prostate cancer has been reported to increase proliferation and invasion. The exact role of AZGP1 in prostate cancer progression remains elusive.

METHOD

AZGP1 knockout and overexpressing prostate cancer cells were generated using a lentiviral system. The effects of AZGP1 under- or over-expression in prostate cancer cells were evaluated by in vitro cell proliferation, migration, and invasion assays. Heterozygous AZGP1± mice were obtained from European Mouse Mutant Archive (EMMA), and prostate tissues from homozygous knockout male mice were collected at 2, 6 and 10 months for histological analysis. In vivo xenografts generated from AZGP1 under- or over-expressing prostate cancer cells were used to determine the role of AZGP1 in prostate cancer tumor growth, and subsequent proteomics analysis was conducted to elucidate the mechanisms of AZGP1 action in prostate cancer progression. AZGP1 expression and microvessel density were measured in human prostate cancer samples on a tissue microarray of 215 independent patient samples.

RESULT

Neither the knockout nor overexpression of AZGP1 exhibited significant effects on prostate cancer cell proliferation, clonal growth, migration, or invasion in vitro. The prostates of AZGP1-/- mice initially appeared to have grossly normal morphology; however, we observed fibrosis in the periglandular stroma and higher blood vessel density in the mouse prostate by 6 months. In PC3 and DU145 mouse xenografts, over-expression of AZGP1 did not affect tumor growth. Instead, these tumors displayed decreased microvessel density compared to xenografts derived from PC3 and DU145 control cells, suggesting that AZGP1 functions to inhibit angiogenesis in prostate cancer. Proteomics profiling further indicated that, compared to control xenografts, AZGP1 overexpressing PC3 xenografts are enriched with angiogenesis pathway proteins, including YWHAZ, EPHA2, SERPINE1, and PDCD6, MMP9, GPX1, HSPB1, COL18A1, RNH1, and ANXA1. In vitro functional studies show that AZGP1 inhibits human umbilical vein endothelial cell proliferation, migration, tubular formation and branching. Additionally, tumor microarray analysis shows that AZGP1 expression is negatively correlated with blood vessel density in human prostate cancer tissues.

CONCLUSION

AZGP1 is a negative regulator of angiogenesis, such that loss of AZGP1 promotes angiogenesis in prostate cancer. AZGP1 likely exerts heterotypical effects on cells in the tumor microenvironment, such as stromal and endothelial cells. This study sheds light on the anti-angiogenic characteristics of AZGP1 in the prostate and provides a rationale to target AZGP1 to inhibit prostate cancer progression.

Zinc-alpha 2 glycoprotein a diagnostic Biomarker for early stage oral Squamous Cell Carcinoma

Objectives

In this study, we investigated the expression of zinc alpha-2 glycoprotein in oral squamous cell carcinoma tissue samples. Additionally, ascertained its association to the oral cancer stage and subscale parameters (TNM).

Methods

This observational study was conducted at Ziauddin University from January to December 2020. Using the Open-Epi software, the sample size of 120 oral squamous cell carcinomas was calculated at 95% confidence interval and a 5% margin of error. Ethical approval was taken from the Institutional Ethical Review Committee. Histologically diagnosed cases of oral squamous cell carcinoma were obtained from the Histopathology Department of Ziauddin University, Karachi. Study data was analyzed through SPSS version-20 and p-value ≤0.05 considered as significant. One-way ANOVA and Multiple linear regression were applied for analysis of data.

Result

In the study, none of the oral squamous cell carcinoma tissue samples from the later stages were stained for ZAG. However 71% (35/49) of the early stage OSCC samples showed positive IHC results for ZAG expression in the cytoplasm. One-way ANOVA indicates that high ZAG expression was significantly associated with smaller tumor size (p<0.001), lymph node involvement (p=0.002), early stages of OSCC (p<0.001) and less differentiated tumor (p=0.001). The site of the tumor was also significantly associated with ZAG staining (p<0.001).

Conclusion

Zinc alpha-2 glycoprotein expressed in the early stages of oral cancer development so that effective treatment modalities can be planned as per the patient's status. This may also assist a clinician to achieve tumor-free surgical margins and monitor the post treatment outcomes.

The Immune-related ceRNA Network in Prognosis of Cervical Cancer

BACKGROUND

Immunotherapy is gaining attention and it is being included as one of the treatment strategies for cancer patients. However, the molecular mechanisms of immune-related genes and their affinity for cervical cancer progression remain unclear. In this study, we have developed an immune-related competing endogenous RNA [ceRNA] network and assessed the tumour infiltrating immune cells towards the prognosis of cervical cancer.

METHODS

Differential RNA expression pattern between stages I and II-IV of cervical cancer patients from The Cancer Genome Atlas [TCGA] was analyzed. Immune-related ceRNA network based on the immune gene signatures were retrieved and their targets were predicted using miRwalk 3.0. CIBERSORT was employed to identify the immune cell types based on their respective transcripts. The prognostic significance of RNAs in the ceRNA network and immune cell subsets was analyzed.

RESULTS

Significant differences in 22 long non-coding RNAs [lncRNAs], 15 microRNAs [miRNAs], and 252 messenger RNAs [mRNAs] between stages I and II-IV of cervical cancer were observed. Further, we shortlisted the 49 immune-related mRNAs based on immune gene signature and predicted their target miRNAs and lncRNAs. A potential ceRNA network of 4 lncRNAs, 10 miRNAs, and 11 mRNAs had a strong correlation for prognosis. Out of 11 protein-coding immune mRNAs, IRF4 and AZGP1 had high degrees of interaction. In addition, the evaluation of immune cell subsets showed increased infiltration of M1 macrophages had better survival outcome.

CONCLUSIONS

We have identified an immune-related ceRNA network based on differentially expressed transcripts between stages I and II-IV which may help predict the prognosis of cervical cancer.

Robust Principal Component Analysis Based On Hypergraph Regularization for Sample Clustering and Co-Characteristic Gene Selection

Extracting genes involved in cancer lesions from gene expression data is critical for cancer research and drug development. The method of feature selection has attracted much attention in the field of bioinformatics. Principal Component Analysis (PCA) is a widely used method for learning low-dimensional representation. Some variants of PCA have been proposed to improve the robustness and sparsity of the algorithm. However, the existing methods ignore the high-order relationships between data. In this paper, a new model named Robust Principal Component Analysis via Hypergraph Regularization (HRPCA) is proposed. In detail, HRPCA utilizes L2,1-norm to reduce the effect of outliers and make data sufficiently row-sparse. And the hypergraph regularization is introduced to consider the complex relationship among data. Important information hidden in the data are mined, and this method ensures the accuracy of the resulting data relationship information. Extensive experiments on multi-view biological data demonstrate that the feasible and effective of the proposed approach.

Identification of potential salivary biomarker panels for oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers worldwide with the maximum number of incidences and deaths reported from India. One of the major causes of poor survival rate associated with OSCC has been attributed to late presentation due to non-availability of a biomarker. Identification of early diagnostic biomarker will help in reducing the disease morbidity and mortality. We validated 12 salivary proteins using targeted proteomics, identified initially by relative quantification of salivary proteins on LC-MS, in OSCC patients and controls. Salivary AHSG (p = 0.0041**) and KRT6C (p = 0.002**) were upregulated in OSCC cases and AZGP1 (p ≤ 0.0001***), KLK1 (p = 0.006**) and BPIFB2 (p = 0.0061**) were downregulated. Regression modelling resulted in a significant risk prediction model (p < 0.0001***) consisting of AZGP1, AHSG and KRT6C for which ROC curve had AUC, sensitivity and specificity of 82.4%, 78% and 73.5% respectively for all OSCC cases and 87.9%, 87.5% and 73.5% respectively for late stage (T3/T4) OSCC. AZGP1, AHSG, KRT6C and BPIFB2 together resulted in ROC curve (p < 0.0001***) with AUC, sensitivity and specificity of 94%, 100% and 77.6% respectively for N0 cases while KRT6C and AZGP1 for N+ cases with ROC curve (p < 0.0001***) having AUC sensitivity and specificity of 76.8%, 73% and 69.4%. Our data aids in the identification of biomarker panels for the diagnosis of OSCC cases with a differential diagnosis between early and late-stage cases.

KRT 15 as a prognostic biomarker is highly expressed in esophageal carcinoma

Aim: To investigate the expression and prognostic value of KRT 15 in esophageal carcinoma. Materials & methods: The expression levels of KRT 15 were measured in 128 cases of esophageal carcinoma and matched adjacent normal tissues by immunohistochemistry and Western blot assays. Results & conclusion: Western blot analysis shown the expression levels of KRT 15 in esophageal carcinoma were significantly higher compared with those in matched adjacent normal tissues (p < 0.001). immunohistochemistry result shown the high-expression rate of KRT 15 in esophageal carcinoma were 56.3%, which was significantly higher than those in normal tissues (35.9%; p = 0.002). KRT 15 high-expression correlated with T stage, lymph node metastasis, tumor node metastasis stage and prognosis (p < 0.05). These data indicate KRT 15 as a prognostic biomarker is highly expressed in esophageal carcinoma.

Overexpression of the zinc-α2-glycoprotein accelerates apoptosis and inhibits growth via the mTOR/PTEN signaling pathway in gastric carcinoma cells

Adipocytokine alpha-2-glycoprotein 1 (AZGP1) is a 41-kDa protein which regulates insulin sensitivity and glycolipid metabolism. Recently, mounting evidence has indicated that AZGP1 plays a vital role in the progression and prognosis of many types of tumors, including hepatocellular carcinoma. Also, previous research has reported that AZGP1 levels are reduced significantly in patients with gastric carcinoma (GC). Here, we aim to assess the potential role and molecular mechanism underlying AZGP1-mediated regulation of GC progression. Both RT-PCR and Western blot methods demonstrated that AZGP1 levels were decreased in all GC cell lines tested, which included AGS, NCI-N87, MKN-28, SGC-7901 and MKN-45, relative to the normal human gastric mucosa epithelial (GES-1) cell line. Cell survival and proliferation rates were correspondingly were reduced, while cell apoptosis and caspase-3 activity were increased in NCI-N87 and SGC-7901 cells with high levels of AZGP1. Additionally, the mTOR signaling pathway was suppressed, whereas PTEN expression was elevated following transfection of NCI-N87 and SGC-7901 cells with an AZGP1 overexpressing plasmid. PTEN inhibition reversed the effects of AZGP1 on cell growth and apoptosis in SGC-7901 cells. Therefore, we conclude that AZGP1 induced apoptosis and growth inhibition in GC cells via the regulation of the mTOR/PTEN signaling pathway.

Elemental Zn and its Binding Protein Zinc-α2-Glycoprotein are Elevated in HPV-Positive Oropharyngeal Squamous Cell Carcinoma

Human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) is biologically distinct from HPV-negative HNSCC. Outside of HPV-status, few tumor-intrinsic variables have been identified that correlate to improved survival. As part of exploratory analysis into the trace elemental composition of oropharyngeal squamous cell carcinoma (OPSCC), we performed elemental quanitification by X-ray fluorescence microscopy (XFM) on a small cohort (n = 32) of patients with HPV-positive and -negative OPSCC and identified in HPV-positive cases increased zinc (Zn) concentrations in tumor tissue relative to normal tissue. Subsequent immunohistochemistry of six Zn-binding proteins—zinc-α2-glycoprotein (AZGP1), Lipocalin-1, Albumin, S100A7, S100A8 and S100A9—revealed that only AZGP1 expression significantly correlated to HPV-status (p < 0.001) and was also increased in tumor relative to normal tissue from HPV-positive OPSCC tumor samples. AZGP1 protein expression in our cohort significantly correlated to a prolonged recurrence-free survival (p = 0.029), similar to HNSCC cases from the TCGA (n = 499), where highest AZGP1 mRNA levels correlated to improved overall survival (p = 0.023). By showing for the first time that HPV-positive OPSCC patients have increased intratumoral Zn levels and AZGP1 expression, we identify possible positive prognostic biomarkers in HNSCC as well as possible mechanisms of increased sensitivity to chemoradiation in HPV-positive OPSCC.

Prognostic alternative splicing signatures and underlying regulatory network in esophageal carcinoma

Alternative splicing (AS) has been widely reported to play an important role in cancers, including esophageal carcinoma (ESCA). However, no study has comprehensively investigated the clinical use of combination of prognostic AS events and clinicopathological parameters. Therefore, we collected 165 ESCA patients including 83 esophageal adenocarcinoma (EAC) and 82 esophageal squamous cell carcinoma (ESCC) patients from The Cancer Genome Atlas to explore the survival rate associated with seven types of AS events. Prognostic predictors for the clinical outcomes of ESCA patients were built. Predictive prognosis models of the alternative acceptor site in ESCA (area under the curve [AUC] = 0.83), alternative donor site in EAC (AUC = 0.99), and alternative terminator site in ESCC (AUC = 0.974) showed the best predictive efficacy. A novel combined prognostic model of AS events and clinicopathological parameters in ESCA was also constructed. Combined prognostic models of ESCA all showed better predictive efficacy than independent AS models or clinicopathological parameters model. Through constructing splicing regulatory network, the expression of AS factor was found to be negatively correlated with the most favorable AS events. Moreover, gene amplification, mutation, and copy number variation of AS genes were commonly observed, which may indicate the molecular mechanism of how the AS events influence survival. Conclusively, the constructed prognostic models based on AS events, especially the combined prognostic models of AS signatures and clinicopathological parameters could be used to predict the outcome of ESCA patients. Moreover, the splicing regulatory network and genomic alteration in ESCA could be used for illuminating the potential molecular mechanism.