The nuclear import receptor Kpnβ1 and its potential as an anticancer therapeutic target.

Many proteins require transport across the nuclear envelope, the physical barrier separating the nucleus from the cytoplasm. Karyopherin β (Kpnβ1) proteins are the major nuclear receptor proteins in the cell that cargo proteins across the nuclear envelope, allowing them to enter and exit the cell nucleus. Karyopherin β1, a major nuclear import receptor, plays an integral role in importing transcription factors, cell signaling proteins, cell cycle proteins, and so forth, into the nucleus, thus playing a crucial role in maintaining normal cell homeostasis. However, cancer cells appear to differentially regulate the expression of the Karyopherin β proteins, presumably in order to maintain increased nuclear transport rates, thus implicating this protein family as a target for cancer therapy. The role of Kpnβ1 in cancer is only now being elucidated, and recent work points to its potential usefulness as an anti-cancer target.