RUNX3 and CAMK2N1 hypermethylation as prognostic marker for epithelial ovarian cancer

Abstract

Treatment of epithelial ovarian cancer consists of surgery plus platinum-taxane based chemotherapy. Neither prognostic nor predictive serum or tissue markers except BRCA1/2 mutations are available thus precluding individualized treatment. Aim of this study is the identification and validation of DNA-methylation markers with prognostic value. Genome-wide array analyses were used to determine methylation patterns in groups of serous EOC with different outcome (PFS < vs. > 3 years, each n 5 6) but comparable clinical parameters. Two hundred and twenty differentially methylated regions in tumor tissue of patients with short vs. long PFS (106 hypo-and 114 hypermethylated regions) were identified. Thirty-five of 37 selected CpG islands were validated by MSP using the same samples as for microarray analyses. Six of these regions were analyzed by targeted nextgeneration bisulfite-sequencing confirming array and MSP results. Validation experiments with an enlarged patient group of Type II EOC samples (PFS <3 years n 5 30; >3 years n 5 18) revealed the CpG island of RUNX3 as significantly more often methylated in patients with short PFS (10/30 vs. 0/18; p < 0.01). Marker combinations with significantly different methylation frequencies in patient groups reached an increased sensitivity with equal specificity (RUNX31CAMK2N1; sens 40%; spec 100%; p < 0.01). RUNX3/CAMK2N1 methylation-positive patients of the array-independent subset (n 5 36) showed a significantly lower PFS (p < 0.01) but no other difference in clinical parameters compared to methylation-negative patients. Genomewide methylation analyses reliably identified markers of potentially prognostic value. Hypermethylation of RUNX3/CAMK2N1 is associated with poor clinical outcome in Type II EOC, also after macroscopic complete resection.

Epigenetics in ovarian cancer

“…Higher resolution methylation arrays: Illumina’s Human Methylation 27 K, Human Methylation 450 K, and custom microarrays, have been utilized in the past seven years in studies with larger sample numbers [11,12,20,69–71] (Table 1). The Cancer Genome Atlas (TCGA), collaboration between the National Cancer Institute and National Human Genome Research Institute, has profiled the genomes of 33 types of cancer, including ovarian cancer.…”

“…Huang et al [95] identified differential methylated regions (DMR) associated with progression-free survival (PFS), and validated the DMR in platinum resistant and sensitive cell lines. Hafner et al [71] evaluated DNA methylation difference between pools of HGSOC DNA with poor or good survival followed by validation in an independent set of samples revealing two genes, RUNX3 and CAM21, to be associated with PFS. In cell lines, increased methylation of these two genes was associated with reduced gene expression.…”

miR-182-5p Promotes Growth in Oral Squamous Cell Carcinoma by Inhibiting CAMK2N1

“…Our study is the first to outline a role for miR-182-5p in the proliferation of OSCC cells. The CAMK2N1 gene, a calcium/calmodulin-dependent protein kinase II inhibitor, is a known potent modulator of tumorigenesis and subsequent tumor growth [15]. CAMK2N1 expression may have a tumor suppressing role in certain cancers, and its dysregulation has been linked to tumorigenesis [25].…”

“…miR-182-5p and U6 primers were designed by and purchased from RiboBio Co., Ltd. (Guangzhou, China). CAMK2N1 primer sequences were designed following the procedures described in Hafner et al [15].…”

Epigenetic loss of heparan sulfate 3‐O‐sulfation sensitizes ovarian carcinoma to oncogenic signals and predicts prognosis

“…Abnormal DNA methylation may serve as a biomarker for early detection, outcome prediction, and individualized treatment . Hypermethylation of several genes, including those involved in DNA repair, AKT/mTOR, redox, apoptosis, cell adhesion and cancer stem cell signaling pathways, was reported to correlate with poor prognosis in ovarian cancer patients. Those epigenetics signatures revealed EOC heterogeneity and prognostic carcinogenesis that probably initiate by the diversity of genetic mutations .…”