Analysis of Essential Elements and Heavy Metals Concentrations in Farm Produce and Investigation of the Influence of Heavy Metal Ions on Triple Negative Breast Cancer Cell Viability.

摘要

Fresh fruits, vegetables, herbs, and processed foods continue to be the major sources of essential and macro elements in humans' diet required for proper body development and function. However, food products can inadvertently be contaminated by toxic heavy metals (HMs) from environmental contamination or during industrial food processing. The deleterious health implications of essential trace and macro elements' deficiency and toxic consequences of heavy metal ions (HMIs) in humans necessitate proactive monitoring of the essential and macro elements and HMIs concentrations in the human diet. The hazardous consequences of HMIs on humans also necessitate the need to fundamentally probe the interactions and possible cytotoxic effects of HMIs on human organs for biomedical study and clinical diagnosis. However, there is no prior study that has investigated the influence of several potentially toxic HMIs on human triple negative breast cancer (TNBC) cells.;Human triple negative breast cancer cells are of great health concern as it disparately and most aggressively affect approximately 20-40% of African American women who have been diagnosed with breast cancer compared to their Caucasian American counterparts. Accordingly, this study investigated a comparative analysis of iron (Fe), calcium (Ca), magnesium (Mg), nickel (Ni), zinc (Zn), copper (Cu), lead (Pb), cadmium (Cd), and chromium (Cr) concentrations in a total of 49 food samples in the Greensboro metropolis, NC, USA by flame atomic absorption spectroscopy (FAAS). A survey questionnaire was further administered to 396 participants in the Greensboro metropolis to evaluate the food consumption pattern and a daily/weekly dietary estimate intake of vegetables, fruits, herbs and processed foods. Additionally, this study investigated the influence of five potentially toxic HMIs (arsenic (As (III)), cadmium (Cd (II)), chromium (Cr (VI)), mercury (Hg (II)), and lead (Pb (II)) on human TNBC (HCC 1806) cell 2 viability using optical microscopy, trypan blue dye-exclusion assays, and Western Blot analysis protocols. The results of the food analysis showed high variability in the concentrations of elements in the fresh fruits, vegetables, herbs and processed foods.;The overall average concentrations Ca (1501 mug/g), Mg (186.5 mug/g), Fe (55.8 mug/g), Zn (22.2 mug/g), Pb (10.2 mug/g), Cu (5.8 mug/g), Cr (<0.1 mug/g), Cd (<0.1 mug/g), and Ni (<0.04 mug/g) were obtained in all food categories. The elements concentrations were generally poorly correlated in the food samples. However, a strong inter-element association between Cu and Fe concentrations (R2 = 1.00) and a weak association between Ca and Fe (R2 = 0.561) were found in the food samples. The results of the food survey analysis showed that the amount of vegetables, fruits, herbs, and processed foods dietary intake varied widely. The results of the TNBC study indicated that the influence of HMIs on TNBC cell viability is highly dependent on the type of HMI, HMI concentration, and duration of TNBC cells exposure to the HMIs treatment. The following results;77%, 66%, 65%, 44%, and 9% TNBC cell deaths, respectively, were observed for As (III), Cd (II), Hg (II), Cr(IV), and Pb (II) ions TNBC treated cells. Light microscopy and cell viability assays revealed that As (III) showed the greatest cytotoxic cell death response while Pb (II) showed the least or relatively insignificant cell death response. The Cd (II), Hg (II), and Cr (VI) ions also showed significant cell death responses. These studies revealed that HMIs cause a differential cytotoxic cell death response in TNBC cells and suggests that they have very different genotoxic targets and implications in their mutagenic potential.