Utility of Circulating Cell-Free DNA in Assessing Microsatellite Instability and Loss of Heterozygosity in Breast Cancer Using Human Identification Approach

Abstract

The diagnostic and prognostic utility of circulating cell-free DNA (cfDNA) in breast cancer (BC) patients was recently reported. Here, we investigated the use of cfDNA to examine microsatellite instability (MSI) and loss of heterozygosity (LOH) for early BC diagnosis. cfDNA and genomic DNA from 41 female BC patients and 40 healthy controls were quantified using NanoDrop spectrophotometry and real-time PCR. The stability of genomic and cfDNA was assessed using a high-resolution AmpFlSTR MiniFiler human identification kit. Significant increases in cfDNA plasma concentrations were observed in BC patients compared to controls. The genotype distribution of the eight autosomal short tandem repeat (STR) loci D7S820, D13S317, D21S11, D2S1338, D18S51, D16S539, FGA, and CSF1PO were in Hardy–Weinberg equilibrium. Significant differences in the allele frequencies of D7S820 allele-8, D21S11 allele-29, allele-30.2, allele-32.2, and CSF1PO allele-11 were seen between BC patients and controls. LOH and MSI were detected in 36.6% of the cfDNA of patients compared to genomic DNA. This study highlights the utility of plasma-derived cfDNA for earlier, less invasive, and cost-effective cancer diagnosis and molecular stratification. It also highlights the potential value of cfDNA in molecular profiling and biomarkers discovery in precision and forensic medicine.

Circulating tumor DNA: from discovery to clinical application in breast cancer

“…Another study showed that the incidence of LOH was significantly correlated with lymph node status in terms of the relative concentration of DNA in preoperative serum in patients with breast cancer, in patients with benign breast disease, and in healthy women ( 36 ). In addition, a study of the differences in MSI and LOH between breast cancer and healthy women showed significant differences in some alleles ( 65 ). These collective findings underscore the value of comprehensive ctDNA studies in the early diagnosis of breast cancer.…”

Advances in Polymeric Colloids for Cancer Treatment

“…Consequently, we have to prepare ourselves more strongly to fight this lethal ailment. Among many approaches, chemotherapy is gaining importance as a way to treat different types of cancers [2][3][4][5][6] but it has been associated with several side effects. The most serious side effects are lymphedema, severe pain, fatigue, loss of appetite, swelling and drainage from the site of surgery, bleeding, infection, and organ dysfunction [7][8][9][10][11][12][13].…”