PhD Scientific Days 2021

PO_II_L: Pathology and Oncology II. Lectures

Investigation of CAIX expression in non-Hodgkin lymphomas

Text of the abstract

Low tissue oxygen levels – hypoxia - have a profound effect on the basic cellular adaptation mechanism. One of the well-studied pathways is the Hypoxia Inducible transcriptional factor 1α (HIF1α) related signaling pathway. The activation of HIF1α induces the expression of several factors that contribute to the survival of neoplastic cells in a hypoxic niche. One of these factors is the carbonic anhydrase IX (CAIX), an endogenous hypoxia marker, which is thought to have a significant role in the pH regulation of the malignant cells. Due to the CAIX enzymatic activity, the extracellular pH becomes acidotic, while the intracellular pH shifts towards a near physiologic alkalic range. The pH change contributes to the degradation of the extracellular matrix and metastasis formation. Primary central nervous system lymphoma (PCNSL) is a rare type of extranodal Non-Hodgkin's lymphoma (NHL), which accounts for approximately 5% of all central nervous system (CNS) tumors. Morphologically, majority of the cases are diagnosed as Diffuse Large B-Cell Lymphoma (CNS-DLBCL). Follicular lymphoma (FL) is an indolent type of lymphoma with B-cell origin.
In our study we aimed the examine the expression of CAIX in FL and in CNS-DLBCL.
Histological samples were taken from patients diagnosed with CNS-DLBCL and FL between 2009-2020 in the Pathology Department, University of Debrecen, Hungary. Tissue samples were examined with routine pathological staining (e.g. H&E, BCL6, MUM1) and CAIX immunohistochemistry. Our investigation also included the examination of MYD88 mutation and c-myc status and CD8 expression in CNS-DLBCL cases. After the preliminary examination with light-microscope (Leica DM2000), the slides were also digitalized with Pannoramic Slide Scanner MIDI (3D Histech Ltd, Budapest, Hungary). Clinical data was exported from the Clinics healthcare IT system (Medsol).
The expression of CAIX showed a trend towards an inverse correlation with CD8 expression in our CNS-DLBCL cases, however, the function of CAIX remains unclear in FL, therefore further research should be considered.
THE PUBLICATION IS SUPPORTED BY THE EFOP-3.6.1-16-2016-00022, EFOP-3.6.3-VEKOP-16-2017-00009 and the ÚNKP-20-3-II-DE-488 NEW NATIONAL EXCELLENCE PROGRAM OF THE MINISTRY FOR INNOVATION AND TECHNOLOGY FROM THE SOURCE OF THE NATIONAL RESEARCH, DEVELOPMENT AND INNOVATION FUND (OM).

University and Doctoral School

Debrecen University Faculty of Medicine, Doctoral School of Clinical Medicine