Evaluating the utility of ZNF331 promoter methylation as a prognostic and predictive marker in stage III colon cancer: results from CALGB 89803 (Alliance).

While epigenomic alterations are common in colorectal cancers (CRC), few epigenomic biomarkers that risk-stratify patients have been identified. We thus sought to determine the potential of ZNF331 promoter hypermethylation (mZNF331) as a prognostic and predictive marker in colon cancer. We examined the association of mZNF331 with clinicopathologic features, relapse, survival, and treatment efficacy in patients with stage III colon cancer treated within a randomized adjuvant chemotherapy trial (CALGB/Alliance89803). Residual tumour tissue was available for genomic DNA extraction and methylation analysis for 385 patients. ZNF331 promoter methylation status was determined by bisulphite conversion and fluorescence-based real-time polymerase chain reaction. Kaplan-Meier estimator and Cox proportional hazard models were used to assess the prognostic and predictive role of mZNF331 in this well-annotated dataset, adjusting for clinicopathologic features and standard molecular markers. mZNF331 was observed in 267/385 (69.4%) evaluable cases. Histopathologic features were largely similar between patients with mZNF331 compared to unmethylated ZNF331 (unmZNFF31). There was no significant difference in disease-free or overall survival between patients with mZNF331 versus unmZNF331 colon cancers, even when adjusting for clinicopathologic features and molecular marker status. Similarly, there was no difference in disease-free or overall survival across treatment arms when stratified by ZNF331 methylation status. While ZNF331 promoter hypermethylation is frequently observed in CRC, our current study of a small subset of patients with stage III colon cancer suggests limited applicability as a prognostic marker. Larger studies may provide more insight and clarity into the applicability of mZNF331 as a prognostic and predictive marker.

Casein kinase 1 (CK1) promotes the proliferation and metastasis of glioma cells via the phosphatidylinositol 3 kinase-matrix metalloproteinase 2 (AKT-MMP2) pathway.

BACKGROUND: Glioma is a type of tumor that usually occurs in the adult central nervous system. Protein kinases have become important targets for oncotherapy since they are closely correlated with signal transduction. The role of the casein kinase 1 (CK1) gene in glioma remains to be fully elucidated. METHODS: The mRNA and protein expression of CK1 were analyzed by Realtime PCR, Western blot and immunohistochemistry. The cell behavior was assayed by MTT, Transwell and cell scratch methods. Cell cycle and cell apoptosis were performed by flow cytometer. Construction of stable cell line was completed by lentivirus infection. The nude mouse model was used for in vivo analysis on the role of CK1 by injecting the cells into subcutaneous tissue, tail vein and cerebral cortex. The prognostic role of CK1 in glioma was evaluated using Kaplan-Meier and Cox regression analyses. RESULTS: immunohistochemical staining demonstrated that the expression of CK1 in glioma samples was correlated with the grade of glioma. Survival analysis using Kaplan-Meier and multivariate analysis by Cox regression indicated that CK1 could be used as an independent prognostic marker for glioma. The methyl thiazolyl tetrazolium (MTT), transwell, and cell scratch assays demonstrated that the CK1 gene promoted cell proliferation and invasion through the phosphatidylinositol 3 kinase/matrix metalloproteinase 2 (AKT-MMP2) signaling pathway. In vivo experiments in mice also confirmed the ability of CK1 to enhance tumor proliferation and metastasis, with the metastatic site being the small intestine. CONCLUSIONS: the expression of CK1 was correlated with glioma grade and patient survival and it may enhance glioma proliferation and metastasis via AKT-MMP2 pathway.