Use of selenium as micronutrients and for future anticancer drug: a review

Selenium suppressed growth of Ehrlich solid tumor and improved health of tumor-bearing mice

Selenium (Se) is an important micronutritional biomolecule in cancer therapy. The current work evaluated the anticancer effect of Se and its ability to improve health of mice with solid Ehrlich carcinoma implanted subcutaneously. Four groups of five female BALB/c mice each were assembled. Ehrlich tumor cells were engrafted into two of them, either with or without Se therapy. The other groups served as control groups, either with or without Se treatment. Se treatment resulted in a notable decrease in both tumor volume and animal body mass in tumor-bearing mice. Treatment with Se markedly increased oxidative stress in tumor while ameliorating oxidative stress in sera of tumors-bearing mice. Similarly, treatment with Se resulted in downregulation of inflammatory cytokines (TNF-α and IL-6) while increasing IL-10 in serum of tumor-bearing mice. Conversely, selenium increased TNF- α and IL-6 and decreased IL-10 in tumor suggesting disruption of tumor immunity. The increased oxidative stress and inflammation in tumor tissue dysregulated cell cycle phases with increase apoptotic tumor cells population in G0/G1 phase. This is supported by the increased levels apoptotic regulating proteins (Bax and caspase-3 and P-53) while decreasing Bcl-2 in the tumor tissue. Treatment with Se also resulted in increased comet parameters indicating DNA damage of tumor cells. Histopathological examination revealed a significant decrease in a number of neoplastic cells within tumor of mice that treated with Se. In conclusion, these findings suggest that Se therapy significantly suppressed solid tumor proliferation and growth while mitigating the health status of tumor-bearing mice.

Doxorubicin encapsulated blend of sitagliptin-lignin polymeric drug delivery system for effective combination therapy against cancer

In this research, a sitagliptin-lignin biopolymer (SL) containing zinc selenide quantum dots (ZnSe QDs) and doxorubicin (doxo) was synthesized. The fabricated polymeric drug delivery system was characterized via FTIR, XRD, SEM, TGA, IR, and DSC. SLQD-Doxo exhibited an irregular surface with a 32 nm diameter and well-defined surface chemistry. Drug loading efficiency was assessed at different concentrations, pH levels, time intervals, and temperatures, and drug kinetics were calculated. Maximum drug release was observed at 6 μmol concentration after 24 h, pH of 6.5 and 45 °C. The maximum drug encapsulation efficiency was 81.75 %. SLQD-Doxo demonstrated 24.4 ± 1.04 % anti-inflammatory activity, and the maximum lipoxygenase inhibition in a concentration-dependent manner was 71.45 ± 2.02 %, compared to indomethacin, a standard anticancer drug. The designed system was applied to breast cancer MCF-7 cells to evaluate anticancer activity. Cytotoxicity of SLQD-Doxo resulted in 24.48 ± 1.64 dead cells and 74.39 ± 4.12 viable cells. Lignin's polyphenolic nature resulted in good antioxidant activity of LLQD-Doxo. The combination of SLQD-Doxo was appropriate for drug delivery at high temperatures and acidic pH of tumor cells compared to healthy cells.

Development of trisubstituted thiophene-3-arboxamide selenide derivatives as novel EGFR kinase inhibitors with cytotoxic activity

Overexpression of EGFR is one of the eminent oncogenic drivers detected in the development of several human cancers. The increasing incidences of mutation-based resistance in the tyrosine kinase domain call upon the need for the development of a newer class of small-molecule TK inhibitors. Accordingly, a new series of symmetrical trisubstituted thiophene-3-carboxamide selenide derivatives was developed via the hybridization of complementary pharmacophores. Most of the compounds showed a modest to excellent antiproliferative action at 20 μM concentration. The utmost antiproliferative activity was portrayed by compound 16e on the selected cancer cell lines with IC50 < 9 μM, the lowest being 3.20 ± 0.12 μM in the HCT116 cell line. Further, it also displayed an impressive EGFR kinase inhibition with an IC50 value of 94.44 ± 2.22 nM concentration. As a corollary of the reported EGFR inhibition, the nature, energy, and stability of the binding interactions were contemplated via in silico studies.

Small-molecule organoselenocyanates: Recent developments toward synthesis, anticancer, and antioxidant activities

Cellular redox homeostasis is very important for the overall cellular development, function, and oxidative stress often disrupts the process. Small-molecule organoselenium compounds exert key roles in maintaining the redox homeostasis during oxidative stress and cancer owing to their notable antioxidant activities. Among different organoselenium compounds, small-molecule organoselenocyanates have attracted much research attention due to their synthetic utilities and therapeutic potentials. Therefore, the development of convenient synthetic methodologies to different classes of organoselenocyanates from various precursors was explored over the years as useful synthetic building blocks. Additionally, considering their inherent redox and antioxidant properties, the development of biologically relevant organoselenocyanates upon their conjugation with the existing drugs and natural products has been chosen for enhancing the drug potencies and in ameliorating the drug-induced side-effects. In the present report, we have discussed some of the very recent and relevant developments on these aspects in a very concise manner.

Progress in the Surface Functionalization of Selenium Nanoparticles and Their Potential Application in Cancer Therapy

As an essential micronutrient, selenium participates in numerous life processes and plays a key role in human health. In the past decade, selenium nanoparticles (SeNPs) have attracted great attention due to their excellent functionality for potential applications in pharmaceuticals. However, the utilization of SeNPs has been restricted by their instability and low targeting ability. Since the existing reviews mainly focused on the applications of SeNPs, this review highlights the synthesis of SeNPs and the strategies to improve their stability and targeting ability through surface functionalization. In addition, the utilization of functionalized SeNPs for the single and co-delivery of drugs or genes to achieve the combination of therapy are also presented, with the emphasis on the potential mechanism. The current challenges and prospects of functionalized SeNPs are also summarized. This review may provide valuable information for the design of novel functionalized SeNPs and promote their future application in cancer therapy.

Therapeutic Benefits of Selenium in Hematological Malignancies

Supplementing chemotherapy and radiotherapy with selenium has been shown to have benefits against various cancers. This approach has also been shown to alleviate the side effects associated with standard cancer therapies and improve the quality of life in patients. In addition, selenium levels in patients have been correlated with various cancers and have served as a diagnostic marker to track the efficiency of treatments or to determine whether these selenium levels cause or are a result of the disease. This concise review presents a survey of the selenium-based literature, with a focus on hematological malignancies, to demonstrate the significant impact of selenium in different cancers. The anti-cancer mechanisms and signaling pathways regulated by selenium, which impart its efficacious properties, are discussed. An outlook into the relationship between selenium and cancer is highlighted to guide future cancer therapy development.

Protective effect of food derived nutrients on cisplatin nephrotoxicity and its mechanism

Platinum-based metal complexes, especially cisplatin (cis-diamminedichloroplatinum II, CDDP), possess strong anticancer properties and a broad anticancer spectrum. However, the clinical application of CDDP has been limited by its side effects including nephrotoxicity, ototoxicity, and neurotoxicity. Furthermore, the therapeutic effects of current clinical protocols are imperfect. Accordingly, it is essential to identify key targets and effective clinical protocols to restrict CDDP-induced nephrotoxicity. Herein, we first analyzed the relevant molecular mechanisms during the process of CDDP-induced nephrotoxicity including oxidative stress, apoptosis, and inflammation. Evidence from current studies was collected and potential targets and clinical protocols are summarized. The evidence indicates an efficacious role of nutrition-based substances in CDDP-induced renal injury.

The Effect of Organoselenium Compounds on Histone Deacetylase Inhibition and Their Potential for Cancer Therapy

Genetic and epigenetic changes alter gene expression, contributing to cancer. Epigenetic changes in cancer arise from alterations in DNA and histone modifications that lead to tumour suppressor gene silencing and the activation of oncogenes. The acetylation status of histones and non-histone proteins are determined by the histone deacetylases and histone acetyltransferases that control gene transcription. Organoselenium compounds have become promising contenders in cancer therapeutics. Apart from their anti-oxidative effects, several natural and synthetic organoselenium compounds and metabolites act as histone deacetylase inhibitors, which influence the acetylation status of histones and non-histone proteins, altering gene transcription. This review aims to summarise the effect of natural and synthetic organoselenium compounds on histone and non-histone protein acetylation/deacetylation in cancer therapy.

Selenium Biofortification of Crop Food by Beneficial Microorganisms

Selenium (Se) is essential for human health, however, Se is deficient in soil in many places all around the world, resulting in human diseases, such as notorious Keshan disease and Keshin–Beck disease. Therefore, Se biofortification is a popular approach to improve Se uptake and maintain human health. Beneficial microorganisms, including mycorrhizal and root endophytic fungi, dark septate fungi, and plant growth-promoting rhizobacteria (PGPRs), show multiple functions, especially increased plant nutrition uptake, growth and yield, and resistance to abiotic stresses. Such functions can be used for Se biofortification and increased growth and yield under drought and salt stress. The present review summarizes the use of mycorrhizal fungi and PGPRs in Se biofortification, aiming to improving their practical use.