hnRNPK-IN-1 is a heterogeneous nuclear ribonucleoprotein K (hnRNPK) binding ligand with Kd values of 4.6 μM and 2.6 μM measured with SPR and MST, respectively. hnRNPK-IN-1 inhibits c-myc transcription by disrupting the binding of hnRNPK and c-myc promoter. hnRNPK-IN-1 induces Hela cells apoptosis and has strongly anti-tumor activities.