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Updated: Aug 23, 2026

Optimization of a Multiplex RNA-based Expression Assay Using Breast Cancer Archival Material
Published on: August 1, 2018
Reduced expression of PTEN correlates with breast cancer progression
Shikha Bose1, Allison Crane, Hanina Hibshoosh
1Department of Pathology, University of California, Los Angeles, California 90048, USA.
Abstract:
PTEN is a tumor-suppressor gene with phosphatase activity that is mutated in a variety of cancers. We analyzed a series of 34 invasive and 18 in situ breast cancers with known molecular status of the PTEN genotype using immunohistochemistry. Reduced PTEN protein expression was seen in 38% of invasive cancers and in 11% of in situ cancers. The frequency of reduced expression was highest in stage II and III cancers. Reduced expression also correlated with aneuploidy. In addition, in tumors with both in situ and invasive components, expression within the ductal carcinoma in situ portion tended to reflect the expression pattern of the invasive component. These data suggest that PTEN expression is frequently reduced in advanced breast cancers.
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