Total RNA was extracted from cultured H4 cells using TRIzol reagent according to the manufacturer's protocol. Briefly, cells were lysed directly in TRIzol, and phase separation was performed by addition of chloroform followed by centrifugation. The aqueous phase was recovered, and RNA was precipitated with isopropanol, washed with 75% ethanol, and resuspended in nuclease-free water. RNA quantity and quality were assessed prior to library preparation. RNA-seq libraries were prepared from total RNA using the Illumina TruSeq RNA Library Preparation Kit v2 according to the manufacturer's protocol, including poly(A) selection, fragmentation, cDNA synthesis, adapter ligation, and PCR amplification.