Can BATF Expression Serve as a Predictive Marker for Treatment Necessity in Chronic Lymphocytic Leukemia?

Chronic lymphocytic leukemia (CLL) is the most common leukemia in Western countries. The clinical outcome of CLL is heterogeneous and is affected by immunogenic properties. The basic leucine zipper transcription factor (BATF) is a key regulator of Th17 and TFH cells, and plays an important role in B cell activation. The role of BATF in CLL pathogenesis remains unclear. This study aimed to evaluate BATF mRNA expression in whole blood and intracellular BATF levels in different lymphocyte subsets of CLL patients and to investigate their potential association with clinical outcomes. Long-term clinical follow-up data were used to compare BATF levels between patients who required treatment and those managed without therapy. BATF mRNA expression in whole blood was significantly higher in patients than in healthy subjects. Similarly, elevated BATF levels were found in CD19+ B, CD3+ T, CD3+CD4+ T helper, CD8+ T, and TFH cells of CLL patients by flow cytometry. A positive correlation was observed between BATF levels and the count of CD5+CD19+ B-CLL cells. Notably, BATF levels in lymphocytes, CD4+T, CD8+ T and TFH cells were lower in CLL patients who required treatment than the levels in patients who required no treatment. Elevated BATF expression in CLL patients suggests its potential role in CLL pathogenesis. Reduced levels of BATF in CD8+ T cells in patients who required treatment may indicate a reduced cytotoxic response against malignant cells. These findings might indicate that BATF expression could serve as a potential biomarker for predicting disease progression and treatment necessity in CLL.