Are trace element concentrations suitable biomarkers for the diagnosis of cancer?

Abstract

Despite advances in cancer research, cancer is still one of the leading causes of death worldwide. An early diagnosis substantially increases the survival rate and treatment success. Thus, it is important to establish biomarkers which could reliably identify cancer patients. As cancer is associated with changes in the systemic trace element status and distribution, serum concentrations of selenium, iron, copper, and zinc could contribute to an early diagnosis. To test this hypothesis, case control studies measuring trace elements in cancer patients vs. matched controls were selected and discussed focusing on lung, prostate, breast, and colorectal cancer. Overall, cancer patients had elevated serum copper and diminished zinc levels, while selenium and iron did not show consistent changes for all four cancer types. Within the tumor tissue, mainly copper and selenium are accumulating. Whether these concentrations also predict the survival probability of cancer patients needs to be further investigated.

Modulation of Intracellular Copper Levels as the Mechanism of Action of Anticancer Copper Complexes: Clinical Relevance

“…Since copper plays an important role in the cellular function and metabolism, the question arises as to whether there are significant differences in Cu levels in cancer patients in comparison with healthy cohorts, and if yes, whether Cu levels can be used as a reliable biomarker of disease progression and response to treatment [ 15 ]. Cu concentrations were determined from emission spectrograms or by flame atomic absorption spectrometry in whole blood, plasma [ 16 ] or serum [ 15 ], toenail [ 17 ], hair [ 18 ], saliva [ 19 ], and tissues [ 20 ]. Many studies reported a positive correlation between circulating Cu levels and cancer progression, in particular breast cancer.…”

The emerging role of selenium metabolic pathways in cancer: New therapeutic targets for cancer

“…6 These results suggest that the Se present in Plasmax protects cells from impairment by lipid peroxidation and ferroptosis. The concentration of Se in tumor tissue is almost fourfold higher compared to that in normal cells, 22,23 in particular, drug-resistant cancer cells, suggesting that cancer cells utilize selenoenzymes to protect themselves from ROS-producing anticancer agents. 1,24 Although the scientific community has known about ferroptosis, a type of programmed cell death, for quite a long time, Stockwell's group coined the term ferroptosis and described its key features.…”

Zinc Signaling in the Mammary Gland: For Better and for Worse

“…However, treatment of cancerous prostate tumors by elevating dietary or serum Zn 2+ , which does not directly affect the “free” Zn 2+ content of prostate cells, proved controversial, and more specific tools were sought [ 98 , 99 ]. In breast cancer patients, measurement of total Zn 2+ in the serum or within the malignant cells demonstrated abnormal concentrations, suggesting the involvement of Zn 2+ dysregulation in progression of this malignancy as well [ 100 , 101 ]. While serum Zn 2+ levels are reduced in most cancers, breast and lung tumor tissues have elevated levels of “free” Zn 2+ when compared to the normal tissue [ 102 , 103 ].…”