Extremely Low-Frequency Electromagnetic Field (ELF-EMF) Induced Alterations in Gene Expression and Cytokine Secretion in Clear Cell Renal Carcinoma Cells.

BACKGROUND: The study aimed to investigate the influence of extremely low-frequency electromagnetic fields (ELF-EMF) on clear cell renal cell carcinoma (ccRCC) by assessing alterations in gene expression and the secretion of cytokines and chemokines. MATERIAL AND METHODS: Three ccRCC cell lines (786-O, 769-P, and CAKI-1) and a healthy HEK293 cell line were subjected to ELF-EMF exposure (frequency 50 Hz, magnetic field strength 4.5 mT) for 30 min daily for 5 days. The study examined the expression of ADAM28, NCAM1, and VEGFC genes, along with the secretion of 30 cytokines and chemokines. RESULTS: Notably, primary tumor-derived cell lines, but not those from metastatic sites, exhibited ADAM28 gene expression, which increased following ELF-EMF exposure. A statistically significant reduction in VEGFC gene expression was observed in 769-P cells after ELF-EMF exposure. Additionally, NCAM1 gene expression was upregulated in HEK293, 769-P, and 786-O cells, representing normal embryonic kidney cells and primary tumor cells, but not in CAKI-1 cells, which model metastatic sites. After EMF exposure, there was a statistically significant decrease in transforming growth factor ß1 (TGF-ß1) concentration in the cell culture supernatants of HEK293 and CAKI-1 cell lines, with no other significant changes in the secretion of tested cytokines. CONCLUSIONS: Given the study's findings and available research, caution is warranted when drawing conclusions about the potential inhibitory effect of ELF-EMF on ccRCC progression. Standardization of experimental models is imperative when assessing the effects of EMF in a human context.

Choosing the Right Cell Line for Acute Myeloid Leukemia (AML) Research.

Immortalized cell lines are widely used in vitro tools in oncology and hematology research. While these cell lines represent artificial systems and may accumulate genetic aberrations with each passage, they are still considered valuable models for pilot, preliminary, and screening studies. Despite their limitations, cell lines are cost-effective and provide repeatable and comparable results. Choosing the appropriate cell line for acute myeloid leukemia (AML) research is crucial for obtaining reliable and relevant results. Several factors should be considered when selecting a cell line for AML research, such as specific markers and genetic abnormalities associated with different subtypes of AML. It is also essential to evaluate the karyotype and mutational profile of the cell line, as these can influence the behavior and response to the treatment of the cells. In this review, we evaluate immortalized AML cell lines and discuss the issues surrounding them concerning the revised World Health Organization and the French-American-British classifications.

Clinical and Molecular Aspects of Iron Metabolism in Failing Myocytes.

Heart failure (HF) is a common disease that causes significant limitations on the organism's capacity and, in extreme cases, leads to death. Clinically, iron deficiency (ID) plays an essential role in heart failure by deteriorating the patient's condition and is a prognostic marker indicating poor clinical outcomes. Therefore, in HF patients, supplementation of iron is recommended. However, iron treatment may cause adverse effects by increasing iron-related apoptosis and the production of oxygen radicals, which may cause additional heart damage. Furthermore, many knowledge gaps exist regarding the complex interplay between iron deficiency and heart failure. Here, we describe the current, comprehensive knowledge about the role of the proteins involved in iron metabolism. We will focus on the molecular and clinical aspects of iron deficiency in HF. We believe that summarizing the new advances in the translational and clinical research regarding iron deficiency in heart failure should broaden clinicians' awareness of this comorbidity.

Regulation and Function of Metal Uptake Transporter NtNRAMP3 in Tobacco.

Natural resistance-associated macrophage protein (NRAMP) genes encode proteins with low substrate specificity, important for maintaining metal cross homeostasis in the cell. The role of these proteins in tobacco, an important crop plant with wide application in the tobacco industry as well as in phytoremediation of metal-contaminated soils, remains unknown. Here, we identified NtNRAMP3, the closest homologue to NRAMP3 proteins from other plant species, and functionally characterized it. A NtNRAMP3-GFP fusion protein was localized to the plasma membrane in tobacco epidermal cells. Expression of NtNRAMP3 in yeast was able to rescue the growth of Fe and Mn uptake defective Δfet3fet4 and Δsmf1 mutant yeast strains, respectively. Furthermore, NtNRAMP3 expression in wild-type Saccharomyces cerevisiae DY1457 yeast strain increased sensitivity to elevated concentrations of iron (Fe), manganese (Mn), copper (Cu), cobalt (Co), nickel (Ni), and cadmium (Cd). Taken together, these results point to a possible role in the uptake of metals. NtNRAMP3 was expressed in the leaves and to a lesser extent in the roots of tobacco plants. Its expression occurred mainly under control conditions and decreased very sharply in deficiency and excess of the tested metals. GUS-based analysis of the site-specific activity of the NtNRAMP3 promoter showed that it was primarily expressed in the xylem of leaf blades. Overall, our data indicate that the main function of NtNRAMP3 is to maintain cross homeostasis of Fe, Mn, Co, Cu, and Ni (also Cd) in leaves under control conditions by controlling xylem unloading.

Expression of Iron Metabolism Proteins in Patients with Chronic Heart Failure.

In heart failure, iron deficiency is a common comorbid disease that negatively influences exercise tolerance, number of hospitalizations and mortality rate, and this is why iron iv supplementation is recommended. Little is known about the changes in iron-related proteins in the human HF myocardium. The purpose of this study was to assess iron-related proteins in non-failing (NFH) vs. failing (FH) human myocardium. The study group consisted of 58 explanted FHs; control consisted of 31 NFHs unsuitable for transplantation. Myocardial proteins expressions: divalent metal transporter (DMT-1); L-type calcium channel (L-CH); transferrin receptors (TfR-1/TfR-2); ferritins: heavy (FT-H) or light (FT-L) chain, mitochondrial (FT-MT); ferroportin (FPN), regulatory factors and oxidative stress marker: 4-hydroxynonenal (4-HNE). In FH, the expression in almost all proteins responsible for iron transport: DMT-1, TfR-1, L-CH, except TfR-2, and storage: FT-H/-L/-MT were reduced, with no changes in FPN. Moreover, 4-HNE expression (pg/mg; NFH 10.6 ± 8.4 vs. FH 55.7 ± 33.7; p < 0.0001) in FH was increased. HNE-4 significantly correlated with DMT-1 (r = -0.377, p = 0.036), L-CH (r = -0.571, p = 0.001), FT-H (r = -0.379, p = 0.036), also FPN (r = 0.422, p = 0.018). Reducing iron-gathering proteins and elevated oxidative stress in failing hearts is very unfavorable for myocardiocytes. It should be taken into consideration before treatment with drugs or supplements that elevate free oxygen radicals in the heart.

Effects of 445 nm, 520 nm, and 638 nm Laser Irradiation on the Dermal Cells.

Background: The invention of non-ionizing emission devices revolutionized science, medicine, industry, and the military. Currently, different laser systems are commonly used, generating the potential threat of excessive radiation exposure, which can lead to adverse health effects. Skin is the organ most exposed to laser irradiation; therefore, this study aims to evaluate the effects of 445 nm, 520 nm, and 638 nm non-ionizing irradiation on keratinocytes and fibroblasts. Methods: Keratinocytes and fibroblasts were exposed to a different fluency of 445 nm, 520 nm, and 638 nm laser irradiation. In addition, viability, type of cell death, cell cycle distribution, and proliferation rates were investigated. Results: The 445 nm irradiation was cytotoxic to BJ-5ta (≥58.7 J/cm2) but not to Ker-CT cells. Exposure influenced the cell cycle distribution of Ker-CT (≥61.2 J/cm2) and BJ-5ta (≥27.6 J/cm2) cells, as well as the Bj-5ta proliferation rate (≥50.5 J/cm2). The 520 nm irradiation was cytotoxic to BJ-5ta (≥468.4 J/cm2) and Ker-CT (≥385.7 J/cm2) cells. Cell cycle distribution (≥27.6 J/cm2) of Ker-CT cells was also affected. The 638 nm irradiation was cytotoxic to BJ-5ta and Ker-CT cells (≥151.5 J/cm2). The proliferation rate and cell cycle distribution of BJ-5ta (≥192.9 J/cm2) and Ker-CT (13.8 and 41.3 J/cm2) cells were also affected. Conclusions: At high fluences, 455 nm, 520 nm, and 638 nm irradiation, representing blue, green, and red light spectra, are hazardous to keratinocytes and fibroblasts. However, laser irradiation may benefit the cells at low fluences by modulating the cell cycle and proliferation rate.

Suppression of NtZIP4A/B Changes Zn and Cd Root-to-Shoot Translocation in a Zn/Cd Status-Dependent Manner.

In tobacco, the efficiency of Zn translocation to shoots depends on Zn/Cd status. Previous studies pointed to the specific contribution of root parts in the regulation of this process, as well as the role of NtZIP4A/B (from the ZIP family; Zrt Irt-like Proteins). Here, to verify this hypothesis, NtZIP4A/B RNAi lines were generated. Then, in plants exposed to combinations of Zn and Cd concentrations in the medium, the consequences of NtZIP4A/B suppression for the translocation of both metals were determined. Furthermore, the apical, middle, and basal root parts were examined for accumulation of both metals, for Zn localization (using Zinpyr-1), and for modifications of the expression pattern of ZIP genes. Our results confirmed the role of NtZIP4A/B in the control of Zn/Cd-status-dependent transfer of both metals to shoots. Furthermore, they indicated that the middle and basal root parts contributed to the regulation of this process by acting as a reservoir for excess Zn and Cd. Expression studies identified several candidate ZIP genes that interact with NtZIP4A/B in the root in regulating Zn and Cd translocation to the shoot, primarily NtZIP1-like in the basal root part and NtZIP2 in the middle one.

Retinoic Acid and Its Derivatives in Skin.

The retinoids are a group of compounds including vitamin A and its active metabolite all-trans-retinoic acid (ATRA). Retinoids regulate a variety of physiological functions in multiple organ systems, are essential for normal immune competence, and are involved in the regulation of cell growth and differentiation. Vitamin A derivatives have held promise in cancer treatment and ATRA is used in differentiation therapy of acute promyelocytic leukemia (APL). ATRA and other retinoids have also been successfully applied in a variety of dermatological conditions such as skin cancer, psoriasis, acne, and ichthyosis. Moreover, modulation of retinoic acid receptors and retinoid X (or rexinoid) receptors function may affect dermal cells. The studies using complex genetic models with various combinations of retinoic acid receptors (RARs) and retinoid X (or rexinoid) receptors (RXRs) indicate that retinoic acid and its derivatives have therapeutic potential for a variety of serious dermatological disorders including some malignant conditions. Here, we provide a synopsis of the main advances in understanding the role of ATRA and its receptors in dermatology.

Identification and characterization of a tobacco metal tolerance protein, NtMTP2.

Metal tolerance proteins (MTPs) from the CDF (Cation Diffusion Facilitator) family are efflux transporters that play a crucial role in metal homeostasis by maintaining optimal metal concentrations in the cytoplasm. Here, a novel tobacco NtMTP2 transporter was cloned and characterized. It encodes a 512 aa protein containing all specific CDF family domains. A GFP-NtMTP2 fusion protein localizes to the tonoplast in tobacco cells. NtMTP2 expression in yeast conferred tolerance to Co and Ni, indicating that the protein mediates transport of both metals, but not Zn, Mn, Cu, Fe, or Cd. Nonetheless, the expression level was not affected by Co or Ni, except for an increase in leaves at high Co concentrations. Its expression in plant parts remained stable during development, but increased in the leaves of older plants. Analysis of tobacco expressing a promoter-GUS construct indicates that the main sites of promoter activity are the conductive tissue throughout the plant and the palisade parenchyma in leaves. Our results suggest that NtMTP2 is a tonoplast transporter mediating sequestration of Co and Ni into vacuoles and an important housekeeping protein that controls the basal availability of micronutrients and plays a role in the sequestration of metal excess, specifically in leaves.

Zn/Cd status-dependent accumulation of Zn and Cd in root parts in tobacco is accompanied by specific expression of ZIP genes.

BACKGROUND: Root-to-shoot translocation of zinc (Zn) and cadmium (Cd) depends on the concentrations of both metals in the medium. A previous study on tobacco (Nicotiana tabacum) pointed to the contribution of NtZIP1, NtZIP2, NtZIP4 and NtIRT1-like in the regulation of this phenomenon. To learn more, Zn and Cd accumulation, root/shoot distribution and the expression of ZIP genes were investigated in the apical, middle and basal root parts. RESULTS: We show that Zn/Cd status-dependent root-shoot distribution of both metals was related to distinct metal accumulation in root parts. At low Zn and Cd in the medium, the apical part contained the highest metal level; at higher concentrations, the middle and basal parts were the major sink for excess metal. The above were accompanied by root part-specific expression pattern modifications of ZIPs (NtZIP1-like, NtZIP2, NtZIP4A/B, NtZIP5A/B, NtZIP5-like, NtZIP8, NtZIP11, NtIRT1, and NtIRT1-like) that fell into four categories with respect to the root part. Furthermore, for lower Zn/Cd concentrations changes were noted for NtZIP5A/B and NtZIP5-like only, but at higher Zn and Cd levels for NtZIP1-like, NtZIP5-like, NtZIP8, NtZIP11, NtIRT1, and NtIRT1-like. NtZIP1, here renamed to NtZIP5B, was cloned and characterized. We found that it was a zinc deficiency-inducible transporter involved in zinc and cadmium uptake from the soil solution primarily by the middle root part. CONCLUSIONS: We conclude that regulation of the longitudinal distribution of Zn and Cd is highly specific, and that the apical, middle and basal root parts play distinct roles in Zn/Cd status-dependent control of metal translocation efficiency to shoots, including the stimulation of Zn translocation to shoots in the presence of Cd. These results provide new insight into the root part-specific unique role of NtZIP5B and other ZIP genes in the longitudinal distribution of zinc and cadmium and their contribution to the regulation of root-to-shoot translocation.

Contribution of NtZIP1-Like to the Regulation of Zn Homeostasis.

Tobacco has frequently been suggested as a candidate plant species for use in phytoremediation of metal contaminated soil but knowledge on the regulation of its metal-homeostasis is still in the infancy. To identify new tobacco metal transport genes that are involved in Zn homeostasis a bioinformatics study using the tobacco genome information together with expression analysis was performed. Ten new tobacco metal transport genes from the ZIP, NRAMP, MTP, and MRP/ABCC families were identified with expression levels in leaves that were modified by exposure to Zn excess. Following exposure to high Zn there was upregulation of NtZIP11-like, NtNRAMP3, three isoforms of NtMTP2, three MRP/ABCC genes (NtMRP5-like, NtMRP10-like, and NtMRP14 like) and downregulation of NtZIP1-like and NtZIP4. This suggests their involvement in several processes governing the response to Zn-related stress and in the efficiency of Zn accumulation (uptake, sequestration, and redistribution). Further detailed analysis of NtZIP1-like provided evidence that it is localized at the plasma membrane and is involved in Zn but not Fe and Cd transport. NtZIP1-like is expressed in the roots and shoots, and is regulated developmentally and in a tissue-specific manner. It is highly upregulated by Zn deficiency in the leaves and the root basal region but not in the root apical zone (region of maturation and absorption containing root hairs). Thus NtZIP1-like is unlikely to be responsible for Zn uptake by the root apical region but rather in the uptake by root cells within the already mature basal zone. It is downregulated by Zn excess suggesting it is involved in a mechanism to protect the root and leaf cells from accumulating excess Zn.

Functional Analysis of NtZIP4B and Zn Status-Dependent Expression Pattern of Tobacco ZIP Genes.

Tobacco is frequently considered as a plant useful for phytoremediation of metal-contaminated soil, despite the mechanisms for regulation of uptake and accumulation being largely unknown. Here we cloned and characterized a new tobacco Zn and Cd transporter NtZIP4B from the ZIP family (ZRT-IRT-Like proteins). It complemented the Zn-uptake defective yeast mutant zrt1zrt2, and rendered the wild type DY1457 yeast more sensitive to Cd. Bioinformatic analysis and transient expression of the NtZIP4B-GFP fusion protein in tobacco leaves indicated its localization to the plasma membrane. Real-time q-PCR based analysis showed that it is expressed in all vegetative organs with the highest level in leaves. The Zn status determined transcript abundance; NtZIP4B was upregulated by Zn-deficiency and downregulated by Zn excess. At the tissue level, in roots NtZIP4B is expressed in the vasculature of the middle part of the roots and in surrounding tissues including the root epidermis; in leaves primarily in the vasculature. Bioinformatic analysis identified two copies of ZIP4 in tobacco, NtZIP4A and NtZIP4B with 97.57% homology at the amino acid level, with the same expression pattern for both, indicating a high degree of functional redundancy. Moreover, the present study provides new insights into the coordinated function of NtZIP1, NtZIP2, NtZIP4, NtZIP5, NtZIP8, NtIRT1, and NtIRT1-like in response to low-to-high Zn status. Leaves were the major site of NtZIP4, NtZIP5, and NtZIP8 expression, and roots for NtZIP1, NtZIP2, NtIRT1, and NtIRT1-like. Contrasting expression level in the apical and basal root parts indicates distinct roles in root-specific processes likely contributing to the regulation of Zn root-to-shoot translocation. In summary, new insight into the role of ZIP genes in Zn homeostasis pointing to their overlapping and complementary functions, offers opportunities for strategies to modify Zn and Cd root/shoot partition in tobacco.

Control of seed dormancy in Arabidopsis by a cis-acting noncoding antisense transcript.

Seed dormancy is one of the most crucial process transitions in a plant's life cycle. Its timing is tightly controlled by the expression level of the Delay of Germination 1 gene (DOG1). DOG1 is the major quantitative trait locus for seed dormancy in Arabidopsis and has been shown to control dormancy in many other plant species. This is reflected by the evolutionary conservation of the functional short alternatively polyadenylated form of the DOG1 mRNA. Notably, the 3' region of DOG1, including the last exon that is not included in this transcript isoform, shows a high level of conservation at the DNA level, but the encoded polypeptide is poorly conserved. Here, we demonstrate that this region of DOG1 contains a promoter for the transcription of a noncoding antisense RNA, asDOG1, that is 5' capped, polyadenylated, and relatively stable. This promoter is autonomous and asDOG1 has an expression profile that is different from known DOG1 transcripts. Using several approaches we show that asDOG1 strongly suppresses DOG1 expression during seed maturation in cis, but is unable to do so in trans Therefore, the negative regulation of seed dormancy by asDOG1 in cis results in allele-specific suppression of DOG1 expression and promotes germination. Given the evolutionary conservation of the asDOG1 promoter, we propose that this cis-constrained noncoding RNA-mediated mechanism limiting the duration of seed dormancy functions across the Brassicaceae.