Mutation-Agnostic Detection of Colorectal Cancer Using Liquid Biopsy-Based Methylation-Specific Signatures.

Detection of methylation patterns in circulating tumor DNA (ctDNA) can offer a novel approach for cancer diagnostics given the unique signature for each tumor type. We developed a next-generation sequencing (NGS)-based assay targeting 32 CpG sites to detect colorectal cancer-specific ctDNA. NGS was performed on bisulfite-converted libraries and status dichotomization was done using median methylation ratios at all targets. We included plasma samples from patients with metastatic colorectal (n = 20) and non-colorectal cancers (n = 8); and healthy volunteers (n = 4). Median methylation ratio was higher in colorectal cancer compared with non-colorectal cancers (P = .001) and normal donors (P = .005). The assay detected ctDNA in 85% of patients with colorectal cancer at a specificity of 92%. Notably, we were able to detect methylated ctDNA in 75% of patients in whom ctDNA was not detected by other methods. Detection of methylated ctDNA was associated with shorter median progression-free survival compared to non-detection (8 weeks versus 54 weeks; P = .027).

Clinical Significance of Immunohistochemical Expression of Neuropeptide Y1 Receptor in Patients With Breast Cancer in Egypt.

Breast cancer (BC) is the most common malignancy in female individuals worldwide. It constitutes about 38.8% of all malignant tumors among Egyptian female individuals. Neuropeptide Y1 receptor (NPY1R) is one of the most abundant peptides in the central and peripheral nervous systems of mammals. It has been found to promote proliferation, vascularization, and stimulate migration in several cell types and tissues and some types of tumor. This the first immunohistochemical study to evaluate the expression of NPY1R in BC and its correlation with clinicopathologic parameters and patient survival. This study included 92 patients with BC. Immunohistochemical staining for NPY1R was done on paraffin-embedded formalin-fixed tissue sections. Statistically significant increases in NPY1R expression was seen in malignant (46/92; 50%) versus non-neoplastic tissue (12/29; 20.7%) (P<0.001). The receiver operating characteristic curve showed that NPY1R is a poor diagnostic test for BC (P<0.001, area under the curve=0.686) in breast tissue. Membranous was the most common pattern of positivity in carcinoma cases (24/46; 52.2%). Statistically significant associations were found between positive NPY1R expression and the presence of metastatic disease (P<0.001), clinical stage (P=0.0003), perineurial invasion (P=0.003), estrogen receptor expression (P=0.004), molecular subtype (P=0.015), Nottingham Prognostic Index risk group (P=0.04), radiotherapy treatment (P=0.01), hormonal treatment (P=0.015), and type of endocrine therapy (P=0.011). Although no significant association was detected between NPY1R-positive and NPY1R-negative cases regarding overall survival and progression-free survival, cases with non-nuclear (membranous+cytoplasmic) expression showed near significantly shorter survival (P=0.063). This study shows that NPY1R was identified in about 50% of malignant BC cases. Its expression correlates with some features of the aggressive disease being associated with metastasis, perineurial invasion, advanced stages, and poor Nottingham Prognostic Index. This suggests a potential prognostic role of NPY1R in BC. Non-nuclear expression of NPY1R seems to be more important in terms of prognosis of BC.

Biochemical study on modifying role of variants of leptin gene and its receptor on serum leptin levels in breast cancer.

The leptin is discharged from breast adipose tissue and is overexpressed in breast cancer (BC). Conflicting relation of leptin with BC was reported. We investigated this association and its impact on leptin level and disease characteristics. The study included 70 females (40 women with pathological proof of invasive BC patients and 30 controls). LEP and LEPR polymorphisms were evaluated by real-time PCR. Serum leptin was estimated by ELISA. Both LEPR and LEP disturbances increase the danger of BC where GG genotype and G allele frequencies of LEPR were higher in patients vs. control. GG genotype increases BC risk with OR (9.1) while G allele predisposes to disease with OR (3.8). Furthermore, LEP A allele was uniquely elevated in patients than healthy ones with OR (2.06). Precise relation of circulating leptin and its polymorphisms with predicting BC may authorize its utilization in early screening.

Leptin receptor gene (A/G) polymorphism rs1137101 and renal cell carcinoma.

Leptin plays an important role in carcinogenesis as leptin/leptin receptor signaling promotes the angiogenesis, proliferation, and inhibits epithelial cell apoptosis. Variants in the leptin receptor gene have potential associations with renal cell carcinoma (RCC). We aimed to investigate association of rs1137101 (A/G) polymorphism at LEPR gene with risk of RCC and patients survival. 123 individuals were classified into group I: 73 RCC patients and group II: 50 healthy controls. Genotyping of the Gln223Arg (A/G) polymorphism rs1137101 at LEPR gene was analyzed using allelic discrimination assay by Real-Time PCR technique. GG genotype was the most frequent among RCC patients (67.1%), while AA genotype was the most frequent in controls (60%); (p < 0.001). By univariate cox regression: gene polymorphism (GG versus GA +AA), stage, histopathologic subtype, and grade were found to affect survival significantly; however, the multivariate analysis showed that only gene polymorphism (GG versus GA +AA) and tumor stage significantly affect survival. LEPR gene variants rs1137101 might be a candidate risk factor for RCC in Egypt. GG genotype is associated with more aggressive tumor behavior and shorter survival compared with GA & AA genotypes so, genotyping of Gln223Arg (A/G) rs1137101 could also predict RCC outcome.