Our results verified the reliability of using serum RUNX3 and SFRP1 methylation status as a noninvasive biomarker for diagnosis of CRC and that combined detection of RUNX3/SFRP1/CEA panel might be a promising strategy for early detection of CRC.
<i>TP53, KRAS, APC</i>) has limited diagnostic sensitivity (40-60%), however, methylated DNA including <i>SEPT9, SFRP1, SDC2</i> can be applied with higher sensitivity (up to 90%) for CRC.Circulating miRNAs (e.g. miR-21, miR-92, miR-141) provide comparably high sensitivity for CRC as the circulating tumor cell mRNA markers (e.g.EGFR, CK19, CK20, CEA).
The Wnt inhibitors were frequently inactivated by promoter methylation in colorectal cancer; however analysis of TCGA data base showed that only the expression of SFRP1 was significantly reduced in tumors compared to normal tissues.
Among the six CRC cell lines (sw-480, sw1116, caco-2, ht-29, colo-205, and hct-116), RT-PCR revealed that sw1116 cells had the lowest expression of SFRP1, while caco-2 cells had the highest SFRP1 expression.
We evaluated the presence and integrity of plasma cfDNA by ALU-based qPCR and the methylation profile of OSMR and SFRP1 genes promoter in a large cohort of colorectal cancer (CRC) patients (n = 114) in comparison to healthy subjects (n = 56) and patients with adenomatous lesions (n = 22).
In MS-HRM analysis, the SFRP1 promoter region was significantly hypermethylated in CRC (55.0% ± 8.4 %) and adenoma tissue samples (49.9% ± 18.1%) compared to normal adult (5.2% ± 2.7%) and young (2.2% ± 0.7%) colonic tissue (<i>P</i> < 0.0001).
Hypermethylation of the selected markers (MAL, PRIMA1, PTGDR and SFRP1) can result in reduced gene expression and may contribute to the formation of colorectal cancer.
In a recent study, we identified frequently methylated genes for cholangiocarcinoma (CDO1, DCLK1, SFRP1 and ZSCAN18), where one of these genes, DCLK1, was also confirmed to be highly methylated in colorectal cancer.
Our results suggest that the myofibroblast-derived SFRP1 protein might be a paracrine inhibitor of epithelial proliferation in NAT areas and loss of this signal may support tumor proliferation in CRC.
The mRNA levels of SFRP1 and SFRP5 were significantly downregulated in 85 and 80% of CRC, respectively; but SFRP4 was overexpressed in 16 of 20 CRC samples.
Similarly, methylation levels of RASSF1A and SFRP1 in the normal-appearing mucosae of distal CRC cases were significantly higher than those in the proximal CRC cases (p < 0.05).
The Wnt/APC/beta-catenin signaling pathway, which includes frizzled-related protein (FRZB), plays a critical role in the development of colorectal cancer, and recent evidence suggests that the functional polymorphism, FRZB Arg324Gly, may be associated with risk for this disease.
This study identifies sFRP1 inactivation at the premalignant stage of colorectal cancer development, indicating that these pathways may be useful targets for chemoprevention strategies in this common solid tumour.
Epigenetic inhibition of sFRP1 transcription was investigated, and increased methylation of the promotor region was demonstrated in an additional cohort of 51 locally advanced colorectal cancers.
One of these genes, SFRP1, belongs to a gene family; we show that hypermethylation of four genes in this family occurs very frequently in colorectal cancer, providing for (i) a unique potential mechanism for loss of tumor-suppressor gene function and (ii) construction of a molecular marker panel that could detect virtually all colorectal cancer.