Comparison of 35 trace elements content in malignant breast tumors with their content in the normal female mammary gland: Original data and a mini-review

Abstract

Objective: In many countries, including Russia, breast cancer ranks first in the incidence of cancers in women. The etiology of this disease remains largely unclear, but there is evidence indicating that disturbances in the somatic homeostasis of trace elements may be involved in the process of oncogenesis. Therefore, this study was aimed at identifying changes in the content of trace elements during malignant transformation of breast tissue.
Methods: For this purpose, an effective method of small sample analysis by means of inductively coupled plasma mass spectrometry was developed. The method makes it possible to determine the content of 35 trace elements in microsamples (with mass ≥ 10 mg) of breast tissue obtained by puncture biopsy. With the help of this technique, the samples of cancerous (n = 43) and normal (n = 38) breast tissue were studied.
Results: In malignant breast tissue, the content of Al, As, B, Cd, Co, Cs, Cu, Mg, Mn, Mo, Ni, Rb, Se, Sr, Ti, Tl, U, V, Zn, and Zr was higher, while the content of Ge, Pb, Sb and Th was lower than in healthy gland tissue. All the identified differences were statistically significant.
Conclusions: The significant disruption of somatic homeostasis of trace elements resulting from malignant transformation of breast tissue has been described, but its cause has not been determined, so additional research is required. Further the method we employ, which we have developed and described here, requires tissue samples weighing only a few milligrams, so it is possible to use it with tissue obtained from puncture tissue biopsies.

Keywords

Breast cancer / Mammary gland of health females / Trace elements / Inductively coupled plasma mass spectrometry

ACKNOWLEDGEMENTS

The authors are extremely grateful to the late head of the thoracic department of the Medical Radiological Research Center, Prof., Dr. P.P. Firsova, and the doctor of this depart-ment, F.V. Medvedev for supplying breast samples.

AUTHORS CONTRIBUTIONS

Vladimir Zaichick: Concept of the study, collection of breast tissue samples, freeze-drying of tissue samples, statistical processing of results, writing and translation of the article. Denis Dogadkin: Samples preparation for ICP-AES, pro-cessing and compilation of the analysis results, discussion of the manuscript text. Irina Gromyak, Dmitry Tyuri: Sam-ples analysis by ICP-AES. Vladimir Kolotov: Development of methodology, critical analysis of the experimental data, discussion of the manuscript text.

FUNDING

This work was supported by the Ministry of Science and Higher Education of the Russian Federation, within the bud-get theme of the Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences.

CONFLICTS OF INTEREST DISCLOSURE

The authors declare they have no conflicts of interest.

INFORMED CONSENT

Obtained.

ETHICS APPROVAL

The Publication Ethics Committee of the Sciedu Press. The journal’s policies adhere to the Core Practices established by the Committee on Publication Ethics (COPE).

PROVENANCE AND PEER REVIEW

Not commissioned; externally double-blind peer reviewed.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are not pub-licly available due to privacy or ethical restrictions.

DATA SHARING STATEMENT

No additional data are available.

OPEN ACCESS

This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/).

COPYRIGHTS

Copyright for this article is retained by the author(s), with first publication rights granted to the journal.

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