TNF and isolated hemihyperplasia: These results suggest that miR-452 plays a key role in post-transcriptional regulation of mRNA levels of RETN, TNFα, and CCL2. To investigate whether RETN, TNFα, and CCL2 expression in IH is regulated by miR-452, miR-452 mimic and non-specific control RNA (miR-452 mimic NC) were introduced into SW872 cells with IH/normoxia exposure, and the mRNA levels of RETN, TNFα, and CCL2 were measured by real-time RT-PCR.