Combination of CA19-9 and Blood Free-Circulating Methylated RUNX3 May Be Useful to Diagnose Stage I Pancreatic Cancer.

BACKGROUND: Although serum carbohydrate antigen 19-9 (CA19-9) is widely used as a useful biomarker of pancreatic cancer for monitoring the response to therapy, it is not recommended for screening of early pancreatic cancer because of its limited sensitivity for small tumors. Thus, it is critical to discover novel serum biomarkers to complement CA19-9 in order to improve sensitivity. Although methylated runt-related transcription factor 3 (RUNX3) is a biomarker of pancreatic cancer, its detection by conventional bisulfite-based methylation assays from a small serum sample amount is very difficult. Therefore, we developed a new methylation assay, the combined restriction digital PCR (CORD) assay, that enables counting of even one copy of a methylated gene in a small DNA sample amount without DNA bisulfite treatment. OBJECTIVES: We evaluated the sensitivity and specificity of serum DNA testing of methylated RUNX3 by the CORD assay in combination with and without CA19-9 for the detection of pancreatic cancer in 55 patients with pancreatic cancer, 12 patients with benign pancreatic disease, and 80 healthy individuals. RESULTS: The CORD assay of methylated RUNX3 had a sensitivity of 50.9% (28/55) and specificity of 93.5% (86/92). Combination of the CORD assay of methylated RUNX3 and CA19-9 resulted in a sensitivity of 85.5% (47/55) and specificity of 93.5% (86/92) for all stages of pancreatic cancer and a sensitivity of 77.8% (7/9) for stage I pancreatic cancer. CONCLUSIONS: ombination of the CORD assay and CA19-9 may provide an alternative screening strategy for detecting early-stage pancreatic cancer.

Methylation analysis of p16, SLIT2, SCARA5, and Runx3 genes in hepatocellular carcinoma.

This study is to investigate the methylation status of multiple tumor suppressor 1 (p16), secreted glycoprotein 2 (SLIT2), scavenger receptor class A, member 5 putative (SCARA5), and human runt-related transcription factor 3 (Runx3) genes in the peripheral blood of hepatocellular carcinoma (HCC).This is a case-control study. The peripheral blood samples were collected from 25 HCC patients, 25 patients with high risk of HCC (defined as "internal control group"), and 25 healthy individuals (defined as "external control group"), respectively. Then the methylation status of p16, SLIT2, SCARA5, and Runx3 genes in the blood samples were analyzed by pyrosequencing. The relationship between the methylation and the clinical features of HCC patients were evaluated.The methylation levels in the 7 CpG loci of p16 gene in HCC patients were low and without statistically significant difference (P > .05) compared to the control groups. Although the methylation levels of CpG3 and CpG4 in SLIT2 gene loci were higher than those of the control groups, there was no statistically significant difference (P > .05). However, the methylation rate of CpG2 locus in SCARA5 gene in HCC patients was significantly higher (P < .05). And the methylation rates of CpG1, CpG2, CpG3, CpG4, CpG5, and CpG8 in Runx3 gene in HCC patients were significantly different to that of control groups (P < .05). We also have analyzed the correlations between the CpG islands methylation of Runx3 or SCARA5 genes and the age, gender, hepatitis B, liver cirrhosis, alpha fetal protein, or hepatitis B surface antigen (HBsAg) of the HCC patients, which all showed no significant correlations (P > .05).The methylation status of SCARA5 and Runx3 genes are abnormal in HCC patients, which may further be used as molecular markers for early auxiliary diagnosis of liver cancer.

An Observational Study on Aberrant Methylation of Runx3 With the Prognosis in Chronic Atrophic Gastritis Patients.

The aim of this study is to discuss whether the methylation levels of Runx3 could be used as the early biomarker for predicting the prognosis in chronic atrophic gastritis (CAG) patients. A total of 200 subjects including 60 controls without CAG (Group 1), 70 patients with mild CAG (Group 2), and 70 patients with moderate and severe CAG (Group 3) were recruited for this cross-sectional investigation in the Department of Gastroenterology in Daqing Oilfield General Hospital from July 2013 to May 2014. The MlALDI-TOF-MS was used to measure the methylation levels of Runx3 in all of the subjects. Real-time quantitative reverse transcription polymerase chain reaction and western blotting were chosen to determine the expression levels of Runx3. The correlations between methylation levels of Runx3 among these CAG patients and their prognosis were shown by logistic regression models. The results demonstrated that the methylation levels of CpG13, CpG14, and CpG15 in Runx3 were higher in Group 3 than those in Groups 1 and 2 (P <0.05), whereas the mRNA and protein expression levels of Runx3 were lower in Group 3 than those in Groups 1 and 2 (P <0.05). There were significantly negative correlations between the methylation levels of Runx3 with its expression and the healing prognosis of CAG patients. In brief, this study proved that the hypermethylation modifications of CpG13, CpG14, and CpG15 in the promoter region of Runx3 could result in the down regulation of Runx3 expression to affect the prognosis of CAG. So the methylation levels of these CpG sites in Runx3 in the peripheral blood can be used as the biomarker for predicting the healing prognosis of CAG patients.

Stepwise cumulation of RUNX3 methylation mediated by Helicobacter pylori infection contributes to gastric carcinoma progression.

BACKGROUND: Helicobacter pylori has been recognized as a definite carcinogen for gastric cancer (GC); however, the pathogenesis of H. pylori infection remains unclear. Runt-related transcription factor 3 (RUNX3) is a candidate tumor suppressor gene whose deficiency is causally related to GC. However, in H. pylori infection-associated GC, the role of RUNX3 has not been studied. METHODS: The authors used real-time methylation-specific polymerase chain reaction analysis to determine methylation status of the RUNX3 promoter in a spectrum of gastric lesions, including 220 samples of chronic atrophic gastritis, 196 samples of intestinal metaplasia, 134 samples of gastric adenoma, 102 samples of dysplasia, and 202 samples of GC with paired noncancerous mucosa tissues and corresponding blood specimens. The association of abnormal methylation with precancerous gastric lesions was evaluated along with the association between RUNX3 methylation and H. pylori infection, and the concordance of methylation levels was investigated between serum and tissues. RESULTS: The results indicated that increasing RUNX3 promoter methylation was correlated with distinct stages of GC progression. GC tissues had the highest methylation proportion (75.2%) compared with precancerous gastric lesions, including chronic atrophic gastritis (15.9%), intestinal metaplasia (36.7%), gastric adenoma (41.8%), and dysplasia (54.9%). H. pylori infection, a major risk factor for GC, contributed to the inactivation of RUNX3 in gastric epithelial cells through promoter hypermethylation. The levels of RUNX3 methylation in serum were in significant concordance with the methylation levels observed in GC tissues (P = .887). CONCLUSIONS: The current findings supported RUNX3 methylation as a risk factors for the carcinogenesis of chronic atrophic gastritis with H. pylori infection and indicated that circulating RUNX3 methylation is a valuable biomarker for the detection of early GC.

RUNX3 promoter methylation in colorectal cancer: its relationship with microsatellite instability and its suitability as a novel serum tumor marker.

BACKGROUND/AIM: RUNX3 is a novel gastric cancer tumor suppressor. RUNX3 promoter hypermethylation is associated with many types of cancer, including colorectal cancer. Furthermore, the RUNX3 promotor is one of the CpG island methylator phenotype (CIMP)-specific promotors. CIMP is a distinct phenotype associated with microsatellite instability (MSI) in colorectal cancer. In this study, the suitability of the quantitative analysis of RUNX3 promoter hypermethylation as a novel serum tumor marker was investigated. Moreover, we investigated the relationship between RUNX3 promoter methylation and MSI in colorectal cancer. PATIENTS AND METHODS: A RUNX3 real-time quantitative methylation-specific PCR (RTQ-MSP) technique we developed was used to analyze the CpG sites in the RUNX3 promoter of 119 colorectal tumors and 344 sera from colorectal cancer patients. MSI analysis of 119 colorectal tumors was performed with five microsatellite markers (BAT25, BAT26, D5S346, D2S123, and D17S250). RESULTS: Proximal colon tumors exhibited significantly higher RUNX3 methylation than their paired normal tissues (p=0.0438). Analysis of the clinicopathological parameters revealed that a proximal location (p=0.0054), lymphatic invasion (p<0.0001), and an advanced pathological stage (p=0.0018) were associated with significantly higher RUNX3 methylation. Assessment of the relationship between RUNX3 methylation and tumor MSI revealed 11 out of 13 tumors with high-frequency MSI (85%) were positive for RUNX3 hypermethylation, significantly more than the tumors with low-frequency MSI or which were microsatellite stable (34%, p=0.0070). In preoperative sera from 344 colorectal cancer patients, significantly higher RUNX3 methylation was associated with lymphatic invasion (p=0.0487) and an advanced pathological stage (p=0.0466). Post-operative follow-up data revealed that recurrence cases exhibited significantly higher preoperative serum RUNX3 methylation than non-recurrence cases (p=0.0003). Concomitant analysis of carcinoembryonic antigen (CEA) levels in the preoperative sera showed that 17.7% (61/344) were CEA-negative but RUNX3 methylation-positive, which means assessing both serum RUNX3 methylation and CEA should improve diagnosis of colorectal carcinoma. CONCLUSION: RTQ-MSP-based quantification of serum RUNX3 methylation is useful for the detection and monitoring of colorectal cancer.

Quantitative analysis of tumor-derived methylated RUNX3 sequences in the serum of gastric cancer patients.

PURPOSE AND EXPERIMENTAL DESIGN: Using real-time quantitative methylation-specific PCR (RTQ-MSP), methylated RUNX3 sequences were quantified and the fractional concentrations of circulating tumor DNA in serum were determined, along with peripheral blood cells collected preoperatively, intraoperatively and postoperatively from 65 patients with gastric cancer. RESULTS: RTQ-MSP was sufficiently sensitive to detect RUNX3 methylation. Quantitative MSP data were expressed in terms of the methylation index, which was defined as the relative amount of methylated RUNX3 sequences divided by the concentration of methylated actin. High levels of methylated RUNX3 sequences were detected in the peripheral circulation of 29% (19 of 65) of the gastric cancer patients. The RUNX3 methylation index was concordant with cancer stage, histology, lymphatic and vascular invasion, and was more sensitive than carcinoembryonic antigen (CEA) as a biomarker. Twenty-nine percent (19 out of 65) of preoperative serum samples had methylated RUNX3 sequences, ranging from 5.2 to 1625955 (median quantity=43 m-index, sensitivity 95.5%, specificity 62.5%, AUC 0.8651). After surgical resection, the median RUNX3 methylation index in serum significantly decreased. These results demonstrate the clinical usefulness and effectiveness of peripheral blood RTQ-MSP for detecting and monitoring gastric cancer after treatment. Furthermore, 5 out of the 30 preoperative control samples of benign disease (cases of panperitonitis due to acute appendicitis or cholecystitis) showed transient RUNX3 methylation which decreased after the operation in accordance with recovery. CONCLUSION: Quantification of epigenetic changes in serum RUNX3 methylation using RTQ-MSP is useful for the detection and monitoring of gastric cancer.