CD9 as a Potential Prognostic Biomarker in Paediatric B-Cell Acute Lymphoblastic Leukaemia

Area of Science:

• Hematology
• Oncology
• Molecular Biology

Background:

• B-cell acute lymphoblastic leukemia (B-ALL) is a significant hematologic malignancy in children.
• Identifying prognostic markers is crucial for tailoring treatment strategies and improving patient outcomes.
• CD9, a cell surface protein, has emerged as a potential biomarker in various cancers.

Purpose of the Study:

• To investigate the role of CD9 expression in predicting specific gene fusions (ETV6::RUNX1, BCR::ABL1, KMT2A) in pediatric B-ALL.
• To evaluate CD9 as a prognostic marker for disease progression and patient outcomes in B-ALL.
• To correlate CD9 expression with clinical features such as lymphadenopathy and white blood cell counts.

Main Methods:

• An observational study involving 488 pediatric B-ALL patients diagnosed via flow cytometry.
• Retrospective analysis of recurrent genetic abnormalities including BCR::ABL1, ETV6::RUNX1, and KMT2A fusion genes.
• Statistical analyses included Fisher's Exact, Pearson's Chi-Square, Mann-Whitney U tests, and univariate/multivariate analyses.

Main Results:

• BCR::ABL1 fusion gene was observed in 9.01% of patients.
• ETV6::RUNX1 gene rearrangement was found in 37.0% of CD9+ and 52.6% of CD9- groups.
• KMT2A gene rearrangement occurred in 8.52% of CD9+ and 10.5% of CD9- groups.
• Lymphadenopathy was significantly associated with the CD9+ group, while higher bone marrow blast counts were noted in the CD9- group.
• No significant difference in survival rates was observed between CD9+ and CD9- groups.

Conclusions:

• CD9 can serve as a surrogate biomarker for predicting B-ALL prognosis.
• CD9 expression helps identify patients with high-risk factors, including lymphadenopathy and potential BCR::ABL1.
• CD9 positivity is associated with a lower frequency of ETV6::RUNX1, suggesting a less favorable genetic profile in this group.