Zinc Deficiency as a General Feature of Cancer: a Review of the Literature

Abstract

Trace elements are minerals that are present in very low concentrations in the human body and yet are crucial for a wide range of physiological functions. Zinc, the second most abundant trace element, is obtained primarily from the diet. After being taken up in the intestine, zinc is distributed to various target organs, where it plays key roles in processes such as immunity, protein folding, apoptosis, and antioxidant activity. Given the important role of zinc in a wide range of enzymatic reactions and physiological processes, zinc deficiency has been identified in a variety of diseases, notably cancer. In recent years, multiple meta-analyses and reviews looking at zinc levels in individual cancer types have been published, as have a plethora of primary studies demonstrating a link between low zinc levels and specific types of cancer. In this review, we summarize recent evidence implicating low zinc concentrations in serum or tissues as a characteristic in a wide range of cancers. We also discuss preliminary findings indicating that zinc level measurement could ultimately become a useful clinical tool for cancer diagnosis and predicting outcomes in patients with cancer. Finally, we suggest future directions for further elucidating the role of zinc deficiency in cancer development and progression.

Keywords: Biomarker; Cancer diagnosis; Cancer prognosis; Trace elements; Zinc deficiency.

Fig. 1

The roles of zinc in human physiology. Some of the most important functions of zinc in the human body include supporting a healthy immune response by promoting differentiation of naïve T cells into activated Th17 cells; facilitating proper folding and activity of zinc-containing proteins; acting as a cofactor for superoxide dismutase (SOD) to exert antioxidant activity; and modulating the stability and activity of p53 to regulate apoptosis. SOD, superoxide dismutase; Th17, T helper 17. References: “Protein folding” representative image from [14] CC BY 4.0. “Apoptosis” representative image from [15] CC BY-NC 4.0. “Antioxidant activity” representative image from [16] CC BY 3.0