Immunophenotyping is essential for diagnosis and classification of most hematopoietic malignancies, and often followed by ancillary studies to understand the predictive and prognostic value of biomarkers. Immunohistochemistry (IHC) provides in-situ coupling of antigen expression with morphology of precursor B- from precursor T-lymphoblastic leukemia/lymphoma. The number of different IHC antibodies that can be applied to bone marrow (BM) biopsies is increasing concurrently with development of flow cytometry and molecular diagnostic methods.

IHC detects scattered tumor cells in Hodgkin’s Lymphoma, Multiple Myeloma (MM) and Acute Myelogenous Leukemia (AML), where key biomarkers may not be detectable by current flow cytometry methods. The goal of this study was to detect BCL-2, Bcl-xL and MCL-1 that are able to predict pre-clinical sensitivity to the drug Venetoclax. We examined the expression of these biomarkers in MM bone samples decalcified using commercially available reagents to determine whether decalcification methods impact BCL-2 family IHC Staining.

Results: MM bone samples (n=59) decalcified in Decal STAT® for 20 min, stained for BCL-2 (124) and Bcl-xL (54H6). MM bone samples (n=7) decalcified in Decal STAT® for 60 min stained for BCL-2 and Bcl-xL. Finally, eleven MM bone samples decalcified in Richard Allan Decal Solution® stained for BCL-2 and Bcl-xL. MCL-1 stained poorly with commercially available decalcification solutions. For MCL-1 to be used, additional staining optimization is required. Conclusion: BCL-2 and BCL-xL proteins can be detected in MM bone samples decalcified with commercially available solutions. With these preliminary results, future studies will pursue the potential for sensitivity to "Venetoclax (ABT-199/GDC-0199)".

Citation Format: Ashley Streator, Eneida C. Villanueva, Burton F. Holmes, Liping Zhang. Assessment of BCL-2, BCL-xL and MCL-1 in bone marrow biopsy samples using VENTANA BenchMark XT automated slide stainer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4656. doi:10.1158/1538-7445.AM2017-4656

©2017 American Association for Cancer Research.
2017
American Association for Cancer Research.