Caspase 12 degrades IκBα protein and enhances MMP-9 expression in human nasopharyngeal carcinoma cell invasion

Cigarette smoking induces the activation of RIP2/caspase-12/NF-κB axis in oral squamous cell carcinoma

Cigarette smoking is one of the major risk factors for the occurrence and progression of oral squamous cell carcinoma (OSCC). Receptor-interacting protein 2 (RIP2) has been involved in mucosal immunity and homeostasis via a positive regulation of nuclear factor κB (NF-κB) transcription factor activity. Caspase-12 can bind to RIP2 and dampen mucosal immunity. However, the roles of RIP2/NF-κB and caspase-12 in OSCC induced by cigarette smoking remain unknown. Herein, we investigated the effects of cigarette smoking on the RIP2/NF-κB and caspase-12 in human OSCC tissues and OSCC cell lines (HSC-3). We first observed that RIP2 mediated NF-κB activation and caspase-12 upregulation in OSCC patients with cigarette smoking and cigarette smoke extract (CSE)-treated HSC-3 cells, respectively. Moreover, we confirmed that the downregulation of RIP2 by siRNA resulted in the reduction of caspase-12 expression and NF-κB activity in the presence of CSE treatment in vitro. In summary, our results indicated that cigarette smoking induced the activation of the RIP2/caspase-12/NF-κB axis and it played an important role in the development of OSCC. The RIP2/caspase-12/NF-κB axis could be a target for OSCC prevention and treatment in the future.

Human Caspase 12 Enhances NF-κB Activity through Activation of IKK in Nasopharyngeal Carcinoma Cells

Human nasopharyngeal carcinoma (NPC) is a highly invasive cancer associated with proinflammation. Caspase-12 (Casp12), an inflammatory caspase, is implicated in the regulation of NF-κB-mediated cellular invasion via the modulation of the IκBα protein in NPC cells. However, the effect mechanisms of Casp12 need to be elucidated. NPC cells were transfected with the full length of human Casp12 cDNA (pC12) and the effect of human Casp12 (hCasp12) on the NF-κB activity was investigated. We found ectopic expression of hCasp12 increased the NF-κB activity accompanied by an increased p-IκBα expression and a decreased IκBα expression. Treatment of BMS, a specific IKK inhibitor, and pC12-transfected cells markedly decreased the NF-κB activity and ameliorated the expression level of IκBα reduced by hCasp12. Co-immunoprecipitation assays validated the physical interaction of hCasp12 with IKKα/β, but not with NEMO. Furthermore, the NF-κB activity of ΔCasp12-Q (a mutated catalytic of hCasp12) transfected cells was concentration-dependently induced, but lower than that of hCasp12-transfected cells. Importantly, the hCasp12-mediated NF-kB activity was enhanced by TNFα stimulation. That indicated a role of the catalytic motif of hCasp12 in the regulation of the NF-κB activity. This study indicated hCasp12 activated the NF-κB pathway through the activation of IKK in human NPC cells.

Analysis of CASP12 diagnostic and prognostic values in cervical cancer based on TCGA database

The present study aims to find a differential protein-coding gene caspase 12 (CASP12) in cervical cancer (CC) based on the (TCGA) database and verify its clinical diagnostic and prognostic values. The transcriptome and clinicopathological data of CC were downloaded from the TCGA database and through screening, we found that PDE2A and CASP12 were independent prognostic factors for CC patients. According to the median expression, the patients were divided into groups with high and low CASP12 and PDE2A expression. There was no difference in survival between PDE2A high and low expression groups (P=0.099), whereas there was a significant difference between CASP12 high and low expression groups (P=0.033). The serum from 68 CC patients (experimental group) and 50 healthy people (control group) was collected to detect the relative expression of CASP12 using qRT-PCR and plotted the ROC curve. The relative expression of CASP12 in the experimental group was significantly lower than in the control group (P<0.05). The area under the curve (AUC) of CASP12 was 0.865. There were statistically significant differences between CASP12 groups with high and low expression in terms of differentiation, lymph node metastasis, tumor size, FIGO staging, and clinical outcomes (P<0.05), but not in terms of age, HPV types and pathological types (P>0.05). The 3-year survival in the CASP12 low expression group was significantly worse than in the CASP12 high expression group (P=0.028). In conclusion, the expression level of CASP12 can be used as a diagnostic and prognostic biomarker for patients with CC.

A Co-Culture System of Three-Dimensional Tumor-Associated Macrophages and Three-Dimensional Cancer-Associated Fibroblasts Combined with Biomolecule Release for Cancer Cell Migration

The objective of this study is to design a cancer invasion model by making use of cancer-associated fibroblasts (CAF) or tumor-associated macrophages (TAM) and gelatin hydrogel microspheres (GM) for the sustained release of drugs. The GM containing adenosine (A) (GM-A) were prepared and cultured with TAM to obtain three-dimensional (3D) TAM aggregates incorporating GM-A (3D TAM-GM-A). The GM-A incorporation enabled TAM to enhance the secretion level of vascular endothelial growth factor. When co-cultured with HepG2 liver cancer cells in an invasion assay, the 3D TAM-GM-A promoted the invasion rate of cancer cells. In addition, the E-cadherin expression level decreased to a significantly greater extent compared with that co-cultured with TAM aggregates incorporating GM, whereas the significantly higher expression of N-cadherin and Vimentin was observed. This indicates that the epithelial-mesenchymal transition event was induced. The GM containing transforming growth factor-β1 (TGF-β1) were prepared to incorporate into 3D CAF (3D CAF-GM-TGF-β1). Following a co-culture of mixed 3D CAF-GM-TGF-β1 and 3D TAM-GM-A and every HepG2, MCF-7 breast cancer cell, or WA-hT lung cancer cell, the invasion rate of every cancer cell enhanced depending on the mixing ratio of 3D TAM-GM-A and 3D CAF-GM-TGF-β1. The amount of matrix metalloproteinase-2 (MMP-2) secreted also enhanced, and the enhancement was well corresponded with that of cancer cell invasion rate. The higher MMP secretion assists the breakdown of basement membrane, leading to the higher rate of cancer cell invasion. This model is a promising 3D culture system to evaluate the invasion ability of various cancer cells in vitro. Impact statement This study proposes a cell culture system to enhance the tumor-associated macrophage function based on the combination of three-dimensional (3D) cell aggregates and gelatin hydrogel microspheres (GM) for adenosine delivery. An additional combination of 3D cancer-associated fibroblasts incorporating GM containing transforming growth factor-β1 allowed cancer cells to enhance their invasion rate. This co-culture system is promising to evaluate the ability of cancer cell invasion for anticancer drug screening.

Common Nevus and Skin Cutaneous Melanoma: Prognostic Genes Identified by Gene Co-Expression Network Analysis

Skin cutaneous melanoma (SCM) is a common malignant tumor of the skin and its pathogenesis still needs to be studied. In this work, we constructed a co-expression network and screened for hub genes by weighted gene co-expression network analysis (WGCNA) using the GSE98394 dataset. The relationship between the mRNA expression of hub genes and the prognosis of patients with melanoma was validated by Gene Expression Profiling Interactive Analysis (GEPIA) database. Furthermore, immunohistochemistry in the Human Protein Atlas was used to validate hub genes and grayscale analysis was performed using ImageJ software. It was found that the yellow module was most significantly associated with the difference between common nevus and SCM, and 13 genes whose expression correlation >0.9 were candidate hub genes. The expression of three genes (STK26, KCNT2, CASP12) was correlated with the prognosis of SCM. STK26 (P = 0.0024) and KCNT2 (P < 0.0001) were significantly different between normal skin and SCM. These three hub genes have potential value as predictors for accurate diagnosis and prognosis of SCM in the future.

Dual role of Endoplasmic Reticulum Stress-Mediated Unfolded Protein Response Signaling Pathway in Carcinogenesis

Cancer constitutes a grave problem nowadays in view of the fact that it has become one of the main causes of death worldwide. Poor clinical prognosis is presumably due to cancer cells metabolism as tumor microenvironment is affected by oxidative stress. This event triggers adequate cellular response and thereby creates appropriate conditions for further cancer progression. Endoplasmic reticulum (ER) stress occurs when the balance between an ability of the ER to fold and transfer proteins and the degradation of the misfolded ones become distorted. Since ER is an organelle relatively sensitive to oxidative damage, aforementioned conditions swiftly cause the activation of the unfolded protein response (UPR) signaling pathway. The output of the UPR, depending on numerous factors, may vary and switch between the pro-survival and the pro-apoptotic branch, and hence it displays opposing effects in deciding the fate of the cancer cell. The role of UPR-related proteins in tumorigenesis, such as binding the immunoglobulin protein (BiP) and inositol-requiring enzyme-1α (IRE1α), activating transcription factor 6 (ATF6) or the protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), has already been specifically described so far. Nevertheless, due to the paradoxical outcomes of the UPR activation as well as gaps in current knowledge, it still needs to be further investigated. Herein we would like to elicit the actual link between neoplastic diseases and the UPR signaling pathway, considering its major branches and discussing its potential use in the development of a novel, anti-cancer, targeted therapy.

Integrative analysis of BSG expression in NPC through immunohistochemistry and public high-throughput gene expression data

BACKGROUND

Though basigin (BSG) was reported to be overexpressed in nasopharyngeal carcinoma (NPC) and correlate with the development of NPC, the molecular basis of BSG in NPC remained elusive. The aim of the research was to investigate BSG expression in NPC and the potential molecular mechanism underlying it.

MATERIALS AND METHODS

BSG expression in NPC tissues was detected with immunohistochemistry. Chi-square test, Kruskal-Wallis test and Spearman correlation test were performed to examine the relationship between BSG expression and the clinico-pathological features as well as EGFR and P-53 expression in NPC. In addition, data from the Human Protein Atlas (HPA) database and oncomine were collected to validate BSG expression in NPC. Meta-analysis was conducted to investigate the association between BSG expression and the clinico-pathological variables of NPC. The prognostic value and the alteration of BSG gene status were also analyzed with data from The Cancer Genome Atlas (TCGA).

RESULTS

BSG presented notably higher expression in NPC tissues than in non-cancer tissues. Moreover, IHC results showed that BSG expression was significantly correlated with tumor progression. A positive correlation was also found between BSG expression and EGFR, P53 expression. Meta-analysis confirmed that BSG was indicative of lymph node metastasis and TNM stage in NPC. Additionally, data from cBioPortal indicated that alteration of BSG gene existed in 5% of NPC cases and BSG correlative genes were obtained from the Co-expression Analysis in TCGA.

CONCLUSION

BSG was overexpressed in NPC and might have an oncogenic effect on the tumorigenesis and progression of NPC.

The association of matrix metalloproteinase-9 promoter polymorphisms with gastric cancer risk: a meta-analysis

Purpose

A variety of studies have observed that the single nucleotide polymorphisms (SNPs) matrix metalloproteinase-9 (MMP-9) gene may be associated with the risk of gastric cancer(GC), and a cytosine (C) to thymine (T) mutation at the -1562 site of the MMP-9 gene promoter is reported to be closely related to the susceptibility. However, because of the conflicting results of these studies, we undertook a systematic meta-analysis to assess the association between the SNPs and the risk of gastric cancer.

Materials and Methods

A computerised literature search was conducted within the databases of PubMed, EMBASE, and ISI Web of Knowledge for studies on the genetic association of MMP-9-1562C/T and gastric cancer published from 2004 to 2015. The pooled odds ratio (OR) and 95% confidence intervals (CI) were estimated for each genotype using the dominant, recessive, co-dominant, and allelic models of the matrix metalloproteinase 9.

Results

Our analysis indicated a significant association of MMP-9-1562C/T with gastric cancer (dominant model [CT+TT/CC]: OR = 1.121, 95% CI = 0.965–1.304; recessive model [CC+CT/TT]: OR = 1.663, 95% CI = 1.148–2.408; co-dominant model [TT/CC]: OR = 1.666, 95% CI = 1.127–2.461; [CT/CC]: OR = 1.078, 95% CI = 0.923–1.259; allelic model [T/C]: OR = 1.150, 95% CI =1.014–1.304).

Conclusions

Our meta-analysis results demonstrated that MMP-9-1562C/T promoter polymorphisms increase the risk of developing gastric cancer.