MiR-34a functions as a tumor suppressor in oral cancer through the inhibition of the Axl/Akt/GSK-3β pathway

Silibinin-Loaded Nanoparticles for Drug Delivery in Gastric Cancer: In Vitro Modulating miR-181a and miR-34a to Inhibit Cancer Cell Growth and Migration

Silibinin (C25H22O10), a notable bioactive flavonolignans, is recognized for its anticancer properties. However, due to its poor water solubility, the objective of this study was to design and synthesize nanocarriers to enhance the solubility of silibinin for effective delivery to AGS gastric cancer cells. This study details the synthesis of PEG400-OA nanoparticles for silibinin delivery to AGS cells. Various physicochemical techniques, including FT-IR, TGA, EDX, FE-SEM, and TEM, were employed to characterize the silibinin-loaded nanoparticles (SLNs), confirming particle size, elemental composition, thermal stability, and paramagnetic properties. The anticancer effects of the SLNs were assessed using MTT assay, scratch test, and Q-RT-PCR. The SLNs exhibited particle sizes ranging from 45 to 60 nm, with thermal stability below 110°C. TEM images suggested a micelles/liposomes structure due to the low polydispersity and spherical shape of the particles. EDX analysis revealed the presence of C, O, N, and P, confirming the incorporation of phospholipids (micelle/liposome) within the SLNs. The IC50 of SLNs in AGS cells was determined to be 28.21 μg/mL. Antimigration effects of SLNs's were demonstrated through the downregulation of miR-181a and upregulation of its potential targets (TGFB, SMAD3, and β-catenin genes), as well as the upregulation of miR-34a and downregulation of its potential target (E-Cadherin antimigration gene). The findings suggest that nanoparticles serve as effective nanocarriers for the targeted delivery of silibinin to cancer cells. Silibinin-loaded micelles/liposomes nanoparticles (SLNs) appear to inhibit cancer cell proliferation and migration by modulating the expressionof miRNAs and their target mRNAs.

Impact of Long-Lasting Environmental Factors on Regulation Mediated by the miR-34 Family

The present review focuses on the interactions of newly emerging environmental factors with miRNA-mediated regulation. In particular, we draw attention to the effects of phthalates, electromagnetic fields (EMFs) and a disrupted light/dark cycle. miRNAs are small non-coding RNA molecules with a tremendous regulatory impact, which is usually executed via gene expression inhibition. To address the capacity of environmental factors to influence miRNA-mediated regulation, the miR-34 family was selected for its well-described oncostatic and neuro-modulatory properties. The expression of miR-34 is in a tissue-dependent manner to some extent under the control of the circadian system. There is experimental evidence implicating that phthalates, EMFs and the circadian system interact with the miR-34 family, in both lines of its physiological functioning. The inhibition of miR-34 expression in response to phthalates, EMFs and light contamination has been described in cancer tissue and cell lines and was associated with a decline in oncostatic miR-34a signalling (decrease in p21 expression) and a promotion of tumorigenesis (increases in Noth1, cyclin D1 and cry1 expressions). The effects of miR-34 on neural functions have also been influenced by phthalates, EMFs and a disrupted light/dark cycle. Environmental factors shifted the effects of miR-34 from beneficial to the promotion of neurodegeneration and decreased cognition. Moreover, the apoptogenic capacity of miR-34 induced via phthalate administration in the testes has been shown to negatively influence germ cell proliferation. To conclude, as the oncostatic and positive neuromodulatory functions of the miR-34 family can be strongly influenced by environmental factors, their interactions should be taken into consideration in translational medicine.