High levels of DJ-1 protein and isoelectric point 6.3 isoform in sera of breast cancer patients.
Bottom Line: Higher DJ-1 levels were significantly associated with advanced clinical grade, according to the TNM classification, negative hormone receptor status, and high Ki-67 labeling index, of biopsied materials; samples showed low DJ-1 protein expression despite upregulated DJ-1 mRNA.Conversely, in the 6 non-cancerous cases, isoforms other than the pI 6.3 isoform were highly expressed, and there was a significant difference in the isoform pattern between breast cancer cases and controls (P = 0.00025).These data indicate that high levels of DJ-1, probably of isoform at pI 6.3, is a candidate serum marker of breast cancer.
Affiliation: Department of Pathology, National Defense Medical College, Saitama, Japan.Show MeSH
Related in: MedlinePlus
Mentions: In situ hybridization of the needle biopsies revealed upregulated levels of DJ-1 mRNA in breast cancer tissue in 171 (98.8%) of 173 pre-therapeutic samples. At the protein level, low expression of DJ-1 was detected in 85 of 173 (49.1%) breast cancer cases by semiquantitative immunohistochemical analysis. Figure2 shows a breast cancer case with high DJ-1 mRNA levels and low expression of DJ-1 protein, whose expression pattern has been observed with secretion and with high DJ-1 levels in the nipple discharge, reported previously.9,10 In cases with low expression of DJ-1 protein, the mean level of DJ-1 protein in the sera was 67.0 ng/mL, significantly higher than that in cases with high expression of DJ-1 protein (23.5 ng/mL).
Affiliation: Department of Pathology, National Defense Medical College, Saitama, Japan.