Chromatin Marks H3K4me3 and H3K9me3 in Triple-Negative Breast Cancer Cell Lines

Triple-negative breast cancer (TNBC) is the most lethal and aggressive breast cancer among all the breast cancer subtypes. Despite several attempts, to date, there is an extensive lack of therapeutic intervention. Hence, there is a dire need for an effective biomarker to timely diagnose TNBC. Here, utilizing super-resolution microscopy, the remodeling structural aspects of euchromatin and heterochromatin in TNBC are studied and the results are compared with non-cancerous and non-TNBC cell lines. The nanoscopic visualization reveals a distinct difference in chromatin remodeling in TNBC in comparison to the other two cell lines. While the euchromatin density is found to increase, the heterochromatin is found to decrease. A complete switching of the heterochromatin-euchromatin ratio is observed in TNBC cells thus proposing that chromatin remodeling and chromatin morphological changes can be pursued as one of the targets for diagnostic purposes. Increased expression of structure specific recognition protein-1(SSRP-1) protein supports the increased rate of chromatin remodeling in breast cancer cell lines. The results may lead to developing a new strategy for diagnosing TNBC patients.