A Novel mRNA-Mediated and MicroRNA-Guided Approach to Specifically Eradicate Drug-Resistant Hepatocellular Carcinoma Cell Lines by Se-Methylselenocysteine

Abstract

Despite progress in the treatment of non-visceral malignancies, the prognosis remains poor for malignancies of visceral organs and novel therapeutic approaches are urgently required. We evaluated a novel therapeutic regimen based on treatment with Se-methylselenocysteine (MSC) and concomitant tumor-specific induction of Kynurenine aminotransferase 1 (KYAT1) in hepatocellular carcinoma (HCC) cell lines, using either vector-based and/or lipid nanoparticle-mediated delivery of mRNA. Supplementation of MSC in KYAT1 overexpressed cells resulted in significantly increased cytotoxicity, due to ROS formation, as compared to MSC alone. Furthermore, microRNA antisense-targeted sites for miR122, known to be widely expressed in normal hepatocytes while downregulated in hepatocellular carcinoma, were added to specifically limit cytotoxicity in HCC cells, thereby limiting the off-target effects. KYAT1 expression was significantly reduced in cells with high levels of miR122 supporting the concept of miR-guided induction of tumor-specific cytotoxicity. The addition of alpha-ketoacid favored the production of methylselenol, enhancing the cytotoxic efficacy of MSC in HCC cells, with no effects on primary human hepatocytes. Altogether, the proposed regimen offers great potential to safely and specifically target hepatic tumors that are currently untreatable.

Identification of differentially expressed HERV-K(HML-2) loci in colorectal cancer

“…KYAT1 uses MSCs as substrates to generate two metabolites, MS and MSP, both of which have antitumor and antiproliferative properties ( Rooseboom et al, 2001 ; Lee et al, 2009 ; Zeng, 2009 ). MicroRNA-guided tumor-specific induction of KYAT1 combined with the MSC has great potential in treating cancers beyond cure ( Selvam et al, 2021 ). As part of the complement system, CR1 was a master regulator of complement activation, chronic inflammation, and innate immune responses ( Jurianz et al, 1999 ).…”

Lacticaseibacillus rhamnosus dfa1 Attenuate Cecal Ligation-Induced Systemic Inflammation through the Interference in Gut Dysbiosis, Leaky Gut, and Enterocytic Cell Energy

“…Notably, TEER values in media culture without Caco-2 cells were used as a blank and were subtracted from the values for the measurements. For measurement of malondialdehyde (MDA; an indicator of reactive oxygen species of lipid peroxidation) [ 105 ], the activated Caco-2 cells were homogenized by the Ultra-Turrax homogenizer (IKA, Staufen, Germany) and centrifuged at 12,000× g for 15 min at 4 °C to separate the supernatant. Then, malondialdehyde (MDA) in the supernatant was measured by an MDA assay kit (colorimetric) (Abcam, Cambridge, UK) according to the manufacturer’s protocol and representing the intracellular reactive oxygen species (ROS).…”

Metabolic Heterogeneity, Plasticity and Adaptation to “Gluta-mine Addiction” in Cancer Cells: The Role of Glutaminase and the GTωA [Glutamine Transaminase – ω-Amidase (Glutaminase II)] Pathway.

“…MSC is both a transaminase and β-lyase substrate of GTK, although transamination is somewhat more favored over the β-lyase reaction [42][43][44]. It was suggested that part of the chemopreventive effect of MSC is due to β-elimination of methylselenol [CH 3 SeH] from MSC [45]. Transamination of MSC yields βmethylselenopyruvate [MSP; CH 3 SeCH 2 C(O)(CO 2 − )] [42].…”

“…In a recent publication, Selvam et al showed that introduction of high levels of GTK into hepatocellular carcinoma cell lines greatly enhanced the cytotoxicity of MSC, possibly as a result of increased oxidative stress [45]. The effect was even more pronounced in the presence of α-keto acid substrates of GTK/GTL, namely, phenylpyruvate and αketo-γ-methiolbutyrate (KMB; synonyms: 4-methylthio-2-oxobutanoate, 4-methylthio-2oxobutyrate) [45].…”