PIK3R1 and diffuse large B-cell lymphoma: In the primary FL tumor, we identified oncogenes with higher chromatin accessibility, including JUN, DICER1, CIITA, SAMD2, MSH6, RUNX1, PIK3R1, and MYD88. In contrast, the relapsed DLBCL tumor exhibited higher chromatin accessibility in genes such as CASP9, STAT3, REL, BCL2, NPM1, and LYN (Fig. 5j).