Therapeutic role of vanillin receptors in cancer

Natural products play significant roles in the development of novel drugs. One of such compounds is vanillin - a natural substance commonly used in food. Anticancer potential of the substance is continually encouraging researchers to conduct further investigations. A rising number of publications describe the role of 4-hydroxy-3-methoxybenzaldehyde (vanillin) in the process of inhibiting tumor growth. Four vanilloid receptors play significant roles in the response of cancer cells to the natural compound. Each of these proteins can be individually affected by vanillin; thus, the substance either leads to inhibition of the cell proliferation or increases the Ca2+ level. The TRPV1, a non-selective cation channel permeable to calcium, acts on cancer development and progression. Thus, vanilloid receptors have the potential to become the target for therapeutical research. Moreover, selective inhibitors of the receptor have proved their efficacy in vitro. CK2α is an antiapoptotic, cancer-sustaining protein and, therefore, the inhibitor of apoptosis. Thus, drugs that exhibit allosteric and ATP-competitive inhibition of the protein might be crucial for cancer therapy. CAMK4 is a protein kinase expression associated with a wide array of cancers. Also, MARK4 is another kinase responsible for the stability of microtubules, overexpressed in many cancer types. Studies concerning this protein revealed that microtubule impairment might be a cancer therapy direction. This review aims to demonstrate the crucial role of described vanilloid receptors in inhibiting the proliferation of cancer cells and to prove the usefulness of using vanillin and its derivatives in the process of drug design.