design: Total RNA was extracted from mouse tumor tissues using the RNeasy Mini Kit; Messenger RNA was purified from total RNA using poly-T oligo-attached magnetic beads. After fragmentation, first-strand cDNA was synthesized using random hexamer primers, followed by second-strand cDNA synthesis. The double-stranded cDNA underwent end repair, A-tailing, adapter ligation, size selection, amplification, and purification.