PTEN and Organ-Specific microRNAs in Metastatic Breast Cancer

This prospective observational study aims to evaluate serum levels of PTEN, a tumor suppressor gene, and organ-specific microRNAs (miRNAs) associated with metastatic patterns in breast cancer. Serum samples will be analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR)-based miRNA profiling and enzyme-linked immunosorbent assay (ELISA)-based PTEN quantification. Three groups will be included: patients with metastatic breast cancer (n=80), patients with non-metastatic early-stage breast cancer (n=40), and healthy controls (n=40). The primary objective is to identify serum biomarkers that differentiate metastatic from non-metastatic disease. Secondary analyses will evaluate correlations between biomarker levels and organ-specific metastatic involvement, including bone, lung, liver, and brain metastases. Findings from this study may support the development of a noninvasive serum-based tool for predicting metastatic patterns in breast cancer.