Incorporation of Functionalized Calcium Phosphate Nanoparticles in Living Cells

Intracellular calcium (Ca2+) is a key signaling element that is involved in a great variety of fundamental biological processes. Thus, Ca2+ deregulation would be involved in the cancer cell progression and damage of mitochondrial membrane and DNA, which lead to apoptosis and necrosis. In this study, we have prepared amorphous calcium phosphate nanoparticles (ACP NPs) for studied their incorporation by endocytosis or electroporation to epithelial, endothelial and fibroblast cells (MCF-7, HUVEC and COS-1 cells, respectively). Our results showed that internalized ACP NPs have cytotoxic effects as a consequence of the increase of the intracellular calcium content. The endocytosis pathways showed a greater cytotoxic effect since calcium ions could easily be released from the nanoparticles and be accumulated in the lysosomes and mitochondria. In addition, the cytotoxic effect could be reversed when calcium ion was chelated with ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA). Modification of ACP NPs by coating with different compounds based on phosphates was also evaluated. The results indicated a reduction of the cytotoxic effect, in the order polyphosphate < phosphonic acid < orthophosphate. A differential cytotoxic effect of ACP-NPs was observed in function of the cell type; the cytotoxic effect can be ordered as i.e., HUVEC > COS-1 > MCF-7. The greater cytotoxic effect caused by the increase of intracellular calcium that is observed in normal cells and the greater resistance of cancer cells suggests new perspectives for cancer research.

A Systematic Review of the Zinc Content of the Normal Human Prostate Gland

The prostate gland is subject to various disorders. The etiology and pathogenesis of these diseases are not well understood. Moreover, despite technological advancements, the differential diagnosis of prostate disorders has become progressively more complex and controversial. It was suggested that the Zn level in prostatic tissue plays an important role in prostatic carcinogenesis and its measurement may be useful as a cancer biomarker. These suggestions promoted more detailed studies of the Zn content in the prostatic tissue of healthy subjects. The present study evaluated by systematic analysis presents the published data for Zn content analyzed in prostatic tissue of "normal" glands. This evaluation reviewed 1885 studies, all of which were published in the years from 1921 to 2020 and were located by searching the databases PubMed, MEDLINE, Scopus, Web of Science, Elsevier-Embase, and Cochrane Library. In addition, the personal archive of the author collected from 1966 to 2020 was also used. The articles were analyzed and "median of means" and "range of means" were used to examine heterogeneity of the measured Zn content in prostates of apparently healthy men. The objective analysis was performed on data from the 105 studies, which included 3735 subjects. It was found that the range of means of prostatic Zn content reported in the literature for "normal" gland varies widely from 17 to 547 mg/kg with median of means 109 mg/kg on a wet mass basis. The Zn content depends on many factors such as analytical method, age, level of androgens, dietary Zn intake, and the prostatic region and fraction of prostate tissue being studied. Finally, because of small sample size and high data heterogeneity, we recommend other primary studies be performed.

Anti-Cancer Effects of 3, 3'-Diindolylmethane on Human Hepatocellular Carcinoma Cells Is Enhanced by Calcium Ionophore: The Role of Cytosolic Ca2+ and p38 MAPK

Purpose: 3,3'-Diindolylmethane (DIM), derived from indole-3-carbinol (I3C) in the Brassica species of cruciferous vegetables, has anticancer effects, but its exact underlying mechanism of action is unknown. We explored the roles of cytosolic free calcium ([Ca2+]i) and p38 MAPK in the anti-cancer effects of DIM in human hepatocellular carcinoma cells. Methods: Cell proliferation was measured with a Cell Counting Kit-8 (CCK-8) and the clonogenic formation assay. Cell apoptosis was examined by flow cytometric analysis and Hoechst dye staining. Cleaved-caspase3, cleaved-PARP, Bax, total, and phosphorylated p38 MAPK were assayed by western blotting. [Ca2+]i was measured with Fluo-3/AM by fluorescence microscopy. A23187, a calcium ionophore, was used to increase [Ca2+]i levels. Results: DIM inhibited cell proliferation in both SMMC-7721 and HepG2 cells in a concentration- and time-dependent manner. DIM also enhanced phosphorylation of p38 MAPK (p-p38), which was attenuated by SB203580. The proliferation inhibition and apoptosis induction by DIM were also blunted. In addition, DIM increased [Ca2+]i in HCC cells, and this effect was inhibited by the calcium chelator, BAPTA-AM, resulting in reduced p-p38 MAPK activation and apoptosis in DIM-treated cells, though the proliferation inhibition by DIM was unchanged. However, the DIM-induced cell proliferation inhibition and apoptosis were significantly enhanced by A23187, a selective calcium ionophore, which was attributed to exaggerated p-p38 MAPK. Conclusions: The calcium ionophore enhanced DIM-induced anti-cancer effects in hepatocellular carcinoma cells, secondary to [Ca2+]i-dependent activation of p38 MAPK. Treatment with a combination of DIM and calcium ionophore may offer a new approach to enhance the chemotherapeutic efficacy in liver cancer.

Associations between age and 50 trace element contents and relationships in intact thyroid of males

BACKGROUND

It is unclear why a prevalence of thyroid dysfunction is higher in the elderly as compared to the younger population. An excess or deficiency of trace element contents in thyroid may play important role in goitre- and carcinogenesis of gland.

AIM

To examine the variation with age of the mass fraction of 50 trace elements in intact (normal) male thyroid.

METHOD

Samples of thyroid parenchyma obtained from 72 healthy males (mean age 37.8 years, range 2-80 years) was investigated. Measurements were performed using a combination of non-destructive and destructive methods: instrumental neutron activation analysis and inductively coupled plasma mass spectrometry, respectively. Tissue samples were divided into two portions. One was used for morphological study while the other was intended for trace element analysis.

RESULTS

There is a statistically significant increase in Cd and Se mass fraction, as well as a decrease in Al, Be, Dy, Ga, Gd, Li, Mn, U, and Y mass fraction in the normal thyroid of male during a lifespan. Moreover, a disturbance of intra-thyroidal chemical element relationships (correlations) with increasing age was found.

DISCUSSION

Our findings suggest that, at least, a goitrogenic and carcinogenic effect of Cd overload and Mn deficiency in the thyroid of old males may be assumed. Many trace elements in human thyroid behave themselves as antagonists or synergists. Therefore, an age-related disturbance in correlations between Mn and other trace element mass fractions in thyroid parenchyma may also contribute to harmful effects on the gland.

CONCLUSION

Age-related changes in intra-thyroidal trace element contents and disturbances in trace element relationships are involved in goitre- and carcinogenesis.

Comparison of 66 chemical element contents in normal and benign hyperplastic prostate

Objective

The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia (BPH) and healthy male.

Methods

We evaluated the prostatic level of 66 chemical elements in 43 patients with BPH and 37 healthy males. Measurements were performed using five instrumental analytical methods.

Results

In the hyperplastic prostates, we have observed a significant increase in the mean level of Bi, Cr, Hg, K, Sb, and Se accompanied a significant decrease in the mean level of Al, Ce, Cs, Dy, Er, Gd, Ho, La, Mo, Nd, Pb, Pr, Sm, Sn, Tb, Tm, U, and Y. No differences were found in the mean prostatic level of other chemical elements including Ag, Al, Au, B, Ba, Be, Br, Ca, Cd, Co, Cu, Fe, Li, Mg, Mn, Na, Nb, Ni, P, Rb, S, Sc, Si, Th, Ti, Tl, Yb, Zn, and Zr between BPH patients and healthy males.

Conclusions

The finding of chemical element contents and correlation between pairs of chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element metabolism in BPH gland. Trace elements Bi, Cr, Hg, K, Sb, and Se may be regarded as the possible tissue biomarkers of hyperplastic transformation of prostate gland. Obtained data did not confirm a critical role of Cd and Pb accumulation in the pathogenesis of BPH. A potential age-related Zn, Fe, and Se deficiency in the prostate tissue has not been found as being involved in the etiology of BPH.