MicroRNA Expression Profile in Early-Stage Breast Cancers.

BACKGROUND: Breast cancer is one of the leading causes of cancer deaths in women. Early diagnosis offers the best hope for a cure. Ductal carcinoma in situ is considered a precursor of invasive ductal carcinoma of the breast. In this study, we carried out microRNA sequencing from 7 ductal carcinoma in situ (DCIS), 6 infiltrating ductal carcinomas (IDC Stage IIA) with paired normal, and 5 unpaired normal breast tissue samples. We identified 76 miRNAs that were differentially expressed in DCIS and IDC. METHODS: Additionally, we provide preliminary evidence of miR-365b-3p and miR-7-1-3p being overexpressed, and miR-6507-5p, miR-487b-3p, and miR-654-3p being downregulated in DCIS relative to normal breast tissue. We also identified a miRNA miR-766-3p that was overexpressed in early-stage IDCs. The overexpression of miR-301a-3p in DCIS and IDC was confirmed in 32 independent breast cancer tissue samples. RESULTS: Higher expression of miR-301a-3p is associated with poor overall survival in The Can-cer Genome Atlas Breast Cancer (TCGA-BRCA) dataset, indicating that it may be associated with DCIS at high risk of progressing to IDC and warrants deeper investigation. CONCLUSION: We also analyzed competing endogenous networks associated with differentially expressed miRNAs and identified LRRC75A-AS1 and MAGI2-AS3 as lncRNAs that potentially play an important role in early-stage breast cancers.

Metaplastic carcinoma of the breast: real-world outcome from a tertiary cancer centre in India.

Metaplastic carcinoma (MPC) is a rare subgroup of breast tumours accounting for <5% of all invasive breast cancers. Histologically confirmed 40 MPC from January 2001 to December 2018 were identified from our electronic database: stage I 2.5% (n = 1), stage II 40% (n = 16), stage III 45% (n = 18) and stage IV 12.5% (n = 5). The mean tumour size was 6 cm, node-negative in 60%, and hormone receptor-negative in 75%. Among the 35 non-metastatic patients, 17 (48.6%) received initial neoadjuvant treatment (NAT), followed by surgery, and only 1 had a complete pathological response. At a median follow-up of 60 months, 17% (n = 6) had a recurrence. All six of them had lung metastasis. The 5-year overall survival (OS) and disease-free survival were 64.4% and 66.3%, respectively. Age more than 46 years (p = 0.027), tumour size more than 5 cm (p = 0.037), and nodal positivity (p = 0.001) were predictors of OS. In node-positive patients, the 5-year OS in those who underwent initial surgery was 80% and after NAT was 21.4% (p = 0.069). In node-negative patients, the 5-year OS after initial surgery was 83.3% and after NAT was 90% (p = 0.380). A statistical significance could not be demonstrated due to the small number of patients. Due to chemoresistance, the concept of initial NAT in MPC of the breast is a subject to be studied in the future. Upfront surgery should be considered for operable diseases (including stage III), followed by a decision on adjuvant therapy. Optimal treatment and effective systemic therapy regimens are yet to be defined.

Role of Circulating Cell-Free DNA in Cancers.

Liquid biopsy is a term used to describe non-invasive tests, which provide information about disease conditions through analysis of circulating cell-free DNA and circulating tumor cells from peripheral blood samples. In patients with cancer, the concentration of cell-free DNA increases, and structural, sequence, and epigenetic changes to DNA can be observed through the disease process and during therapy. Furthermore, cell-free DNA released by the tumor contains the same variants as those in the tumor cells. Therefore, cell-free DNA allows non-invasive assessment of cancer in real time. This review summarizes the origin of cell-free DNA, recent advancements in the detection of cell-free DNA, a possible role in metastasis, and its importance as a non-invasive diagnostic assay for cancer.