Role of Intracystic Cytokines and Nitric Oxide in Ovarian Neoplasms

Elevated Interleukin-6 Levels in the Circulation and Peritoneal Fluid of Patients with Ovarian Cancer as a Potential Diagnostic Biomarker: A Systematic Review and Meta-Analysis

Ovarian cancer (OC) is one of the most lethal cancers, largely due to a late diagnosis. This study aimed to provide a comprehensive meta-analysis on the diagnostic performance of IL6 in the blood and ascites separately for advanced and early-stage OC. We included 37 studies with 6948 participants detecting serum or plasma IL6. The plasma/serum IL6 mean level in the late-stage OC was 23.88 pg/mL (95% CI: 13.84-41.23), and the early-stage OC was 16.67 pg/mL (95% CI: 510.06-27.61), significantly higher than the healthy controls at 3.96 pg/mL (95% CI: 2.02-7.73), but not significantly higher than those found in the controls with benign growths in the ovary, which was 9.63 pg/mL (95% CI: 4.16-22.26). To evaluate IL6 in ascites as a diagnostic marker, we included 26 studies with 1590 participants. The mean level of ascitic IL6 in the late-stage OC was 3676.93 pg/mL (95% CI: 1891.7-7146.7), and the early-stage OC was 1519.21 pg/mL (95% CI: 604.6-3817.7), significantly higher than the benign controls at 247.33 pg/mL (95% CI: 96.2-636.0). There was no significant correlation between the levels of circulating and ascitic IL6. When pooling all OC stages for analysis, we found that serum/plasma IL6 provided 76.7% sensitivity (95% CI: 0.71-0.92) and 72% specificity (95% CI: 0.64-0.79). Ascitic IL6 provided higher sensitivity at 84% (95% CI: 0.710-0.919) and specificity at 74% (95% CI: 0.646-0.826). This study highlights the utility of ascitic IL6 for early detection of OC.

Nerve growth factor orchestrates NGAL and matrix metalloproteinases activity to promote colorectal cancer metastasis

PURPOSE

Colorectal cancer (CRC) is one most cancer type of high incidence and high mortality rate. Metastasis play an important role in survival rate and life quality of colorectal cancer patients. Nerve growth factor (NGF) has been shown to be involved in the metastasis and deterioration in many cancers, but the detail mechanisms in promoting the metastasis of colorectal cancer remain unknown. In this study, we aimed to explore the mechanism of NGF promoting colorectal cancer metastasis to provide new insights for developing NGF anti-colorectal cancer drugs.

METHODS

We examined the expression of NGF in human colorectal cancer by immunohistochemical staining, and Western blot to evaluate the relationship between NGF and colorectal cancer metastasis. Using biochemical experiments including wound healing assay, transwell migration and invasion assay, RT-PCR, Western blot and ELISA to explore the relative mechanism of NGF promoting colorectal cancer cells metastasis in vivo.

RESULTS

Our results found that the high expression of NGF was related with high incidence of metastasis. The binding of NGF to TrkA phosphorylated TrkA, which activated MAPK/Erk signaling pathway increasing the expression NGAL to enhance the activity of MMP2 and MMP9, promoted colorectal cancer metastasis.

CONCLUSION

Our finding demonstrated that NGF increased NGAL expression to enhance MMPs activity to promoted colorectal cancer cell metastasis by TrkA-MAPK/Erk axis.

Effect of m6A RNA Methylation Regulators on Malignant Progression and Prognosis in Renal Clear Cell Carcinoma

Objectives: This study aims to explore the roles of 13 m6A RNA methylation regulators in clear cell renal cell carcinoma (ccRCC), and identify a risk signature and prognostic values of m6A RNA methylation regulators in ccRCC. Materials and Methods: RNA sequence data of ccRCC was obtained from The Cancer Genome Atlas (TCGA) database. Differentially expressed of 13 m6A RNA methylation regulators in ccRCC stratified by different clinicopathological characteristics were unveiled using "limma" package in R version 3.6.0. Cox regression and LASSO analyses were conducted to identify the powerful independent prognostic factors in ccRCC associated with overall survival (OS). Protein-protein interaction (PPI) network and correlation analyses of the 13 m6A RNA methylation regulators were performed using "STRING" and R package, respectively. Principal component analysis (PCA) was also done using R. In addition, gene ontology (GO), GSEA and Kyoto Encyclopedia of Genes and Genomes pathways were used to functionally annotate the differentially expressed genes in different subgroups. Results: Most of the 13 m6A RNA methylation regulators are differentially expressed in ccRCC tissue samples stratified by different clinicopathological characteristics in 537 patients. Next, a risk signature for predicting prognosis of ccRCC patients, was established based on two powerful independent prognostic m6A RNA methylation regulators (METTL14 and METTL3). Then, two subgroups (cluster1 and 2) were identified by consensus clustering to the two powerful independent factors and the cluster1 had a poorer prognosis than cluster2. Furthermore, the genes in cluster1 were significantly enriched in cancer-related pathways, biological process, and hallmarks, including "cell adhesion molecules (CAMs)," "leukocyte migration," "Wnt/β-catenin signaling," and so on. Conclusion: M6A RNA methylation regulators play important roles in the initiation and progression of ccRCC and provide a novel sight to understand m6A RNA modification in ccRCC.

IL-8 promotes cell migration through regulating EMT by activating the Wnt/β-catenin pathway in ovarian cancer

Interleukin‐8 (IL‐8), as an inflammatory chemokine, has been previously shown to contribute to tumorigenesis in several malignancies including the ovarian cancer. However, little is known about how IL‐8 promotes the metastasis and invasion of ovarian cancers cells. In this study, we found that IL‐8 and its receptors CXCR1 and CXCR2 were up‐regulated in advanced ovarian serous cancer tissues. Furthermore, the level of IL‐8 and its receptors CXCR1 and CXCR2 expression were associated with ovarian cancer stage, grade and lymph node metastasis. In vitro, IL‐8 promoted ovarian cancer cell migration, initiated the epithelial‐mesenchymal transition (EMT) program and activated Wnt/β‐catenin signalling. However, when treated with Reparixin (inhibitor of both IL‐8 receptors CXCR1 and CXCR2), effect of both endogenous and exogenous IL‐8 was reversed. Together, our results indicated that IL‐8 triggered ovarian cancer cells migration partly through Wnt/β‐catenin pathway mediated EMT, and IL‐8 may be an important molecule in the invasion and metastasis of ovarian cancer.

IL-6 and IL-8 as Prognostic Factors in Peritoneal Fluid of Ovarian Cancer

The objectives of the study were to analyze the dosage of a cytokine panel (IL2, IL5, IL6, IL8, IL10, and TNF-α) in the peritoneal fluid and relate the dosage of these cytokines to prognostic para- meters and survival in ovarian cancer. Peritoneal fluid was collected intraopera- tively from 29 patients with primary malignant ovarian neoplasia. Cytokine panel dosing was performed with ELISA. Comparisons of cytokines with prognostic factors were performed using the Wilcoxon-Mann-Whitney test. ROC curves were used to determine the cutoff value of NLR, PLR, and IL6. Univariate and multivariate analysis of disease-free survival (DFS) or overall survival (OS) were performed (Kaplan-Meier and Cox regression). The differences were considered significant when the value of p < .05. Higher levels of IL-6 were related to a neutrophil-lymphocyte ratio (NLR) >3.18 (p = .04), a platelet-lymphocyte ratio (PLR) >219.23 (p = .0051), CA-125 levels >35 U/mL (p = .0019), stage IIIC (p = .0203), and DFS ≤ 24 months (p = .0267). For IL-8, higher levels were related to PLR > 219.23 (p = .0426), and CA-125 >35 U/mL (p = .0292). In the univariate analysis, IL-6 levels ≥87.23 in peritoneal fluid had a relationship with shorter DFS at significance threshold (p = .05), and with a shorter OS (p = .039). Multivariate survival analysis proved that IL-6 level in the peritoneal fluid was an independent predictor of OS. Therefore, IL-6 and IL-8 in peritoneal lavage were related to poor prognostic factors. These cytokines may represent new biomarkers for ovarian cancer therapies.

Fluid shear stress-induced IL-8/CXCR signaling in human ovarian cancer cells

Background

Interleukin-8 (IL-8) released from mechanosensitive cancer cells plays a key role in the inflammation and metastasis of solid carcinomas. In this study, we have explored IL-8 and its receptors signal transduction process of human ovarian cancer cells under conditions of FSS.

Methods

After the fluid shear stress was loaded, LightCycler™ system and quantitative sandwich ELISA were employed to assay the IL-8 mRNA expression and protein production, respectively. IL-8 reporter gene pEGFP1-IL8USCS was constructed for determining IL-8 gene transcriptional activation through gene transfer and flow cytometric analysis. NF-κB nuclear translocation was observed by immunocytofluorescent staining. Western blot was used to examine IκB phosphorylation and degradation. RT-PCR, Northern blot and immunofluorescence were used to determine the expression of a cell-surface chemokine receptor CXCR2 at mRNA and protein levels.

Results

IL-8 mRNA expression and protein production had biphasic responses to low shear stress (1.5 dyne/cm²), with the peaks at 1 and 2 h respectively. There was an increase in enhanced green fluorescent protein expression in pEGFP1-IL8USCS-transfected SKOV3 cells subjected to a fluid shear stress of 1.5 dyne/cm² for 2 h. Following the application of shear stress of 1.5 dyne/cm², NF-κB p65 became detectable in the cell nuclei, and Phosphorylated IκB in cell lysates increased significantly. CXCR2, which was constitutively present on the surface of SKOV3 cells, increased following exposure to fluid shear stress for 60 min.

Conclusions

Fluid shear stress triggered IL-8/CXCR2 signaling of SKOV3 cells is an early gene activation, and the activation can be mediated through NF-κB. This observation suggested that fluid shear stress-induced IL-8 activation and the downstream signal pathways may have an important contribution to the pathogenesis and development of both inflammation and metastasis of ovarian carcinomas.