Non-Coding RNAs as Potential Targets for Diagnosis and Treatment of Oral Lichen Planus: A Narrative Review.

Oral lichen planus (OLP) is a chronic inflammatory disease that is characterized by the infiltration of T cells into the oral mucosa, causing the apoptosis of basal keratinocytes. OLP is a multifactorial disease of unknown etiology and is not solely caused by the malfunction of a single key gene but rather by various intracellular and extracellular factors. Non-coding RNAs play a critical role in immunological homeostasis and inflammatory response and are found in all cell types and bodily fluids, and their expression is closely regulated to preserve normal physiologies. The dysregulation of non-coding RNAs may be highly implicated in the onset and progression of diverse inflammatory disorders, including OLP. This narrative review summarizes the role of non-coding RNAs in molecular and cellular changes in the oral epithelium during OLP pathogenesis.

Anti­tumor properties of FoxO1 in YD­9 oral squamous cell carcinoma cells.

Oral squamous cell carcinoma (OSCC) is a tumor with a poor prognosis and a high recurrence rate. Despite its high annual incidence worldwide, appropriate therapeutic strategies have not yet been developed. Consequently, the 5­year survival rate for OSCC is low when advanced stages or recurrence is diagnosed. Forkhead transcriptional factor O1 (FoxO1) is a key mediator for maintaining cellular homeostasis. FoxO1 can function as a tumor suppressor as well as an oncogene depending on the cancer type. Therefore, the precise molecular functions of FoxO1 need to be validated, considering intracellular factors and the extracellular environment. To the best of our knowledge, however, the roles of FoxO1 in OSCC have not yet been defined. The present study examined FoxO1 levels under pathological conditions (oral lichen planus and oral cancer) and selected an appropriate OSCC cell line (YD­9). Crispr/Cas9 was used to generate FoxO1­deficient YD­9 cells in which the protein levels of phospho ERK and phospho STAT3 were upregulated, promoting cancer proliferation and migration. In addition, FoxO1 reduction increased the levels of the cell proliferation markers phospho H3 (Ser10) and PCNA. FoxO1 loss significantly reduced cellular ROS levels and apoptosis in YD­9 cells. Collectively, the present study demonstrated that FoxO1 exerted an anti­tumor effect by suppressing proliferation and migration/invasion but promoting oxidative stress­linked cell death in YD­9 OSCC cells.

Antioxidant and Antiproliferative Activity of Finasteride against Glioblastoma Cells.

Glioblastoma is an actively growing and aggressive brain tumor with a high propensity of recurrence. Although the surgical removal of tumor mass is the primary therapeutic option against glioblastoma, supportive pharmacotherapy is highly essential due to incredibly infiltrative characteristic of glioblastoma. Temozolomide, an FDA-approved alkylating agent, has been used as a first-line standard pharmacological approach, but several evident limitations were repeatedly reported. Despite additional therapeutic options suggested, there are no medications that successfully prevent a recurrence of glioblastoma and increase the five-year survival rate. In this study, we tested the possibility that finasteride has the potential to be developed as an anti-glioblastoma drug. Finasteride, an FDA-approved medication for the treatment of benign prostate hyperplasia and androgenic alopecia, is already known to pass through the blood-brain barrier and possess antiproliferative activity of prostate epithelial cells. We showed that finasteride inhibited the maintenance of glioma stem-like cells and repressed the proliferation of glioblastoma. Mechanistically, finasteride lowered intracellular ROS level by upregulating antioxidant genes, which contributed to inefficient ß-catenin accumulation. Downregulated ß-catenin resulted in the reduction in stemness and cell growth in glioblastoma.

Ginsenoside F2 induces cellular toxicity to glioblastoma through the impairment of mitochondrial function.

BACKGROUND: Glioblastoma (GBM) is the most aggressive tumor residing within the central nervous system, with extremely poor prognosis. Although the cytotoxic effects of ginsenoside F2 (GF2) on GBM were previously suggested, the precise anti-GBM mechanism of GF2 remains unclear. The aim of this study was to explore the anti-cancer molecular mechanism of GF2 toward human GBM. METHODS: GF2-driven cellular toxicity was confirmed in two different GBM cells, U373 and Hs683. To test mitochondrial impairment driven by GF2, we examined the mitochondrial membrane potential, OCR, and ATP production. An intracellular redox imbalance was identified by measuring the relative ratio of reduced glutathione to oxidized glutathione (GSH/GSSG), glutaredoxin (GLRX) mRNA expression, intracellular NAD+ level, and AMPK phosphorylation status. RESULTS: GF2 increased the percentage of cleaved caspase 3-positive cells and γH2AX signal intensities, confirming that GF2 shows the cytotoxicity against GBM. GO enrichment analysis suggested that the mitochondrial function could be negatively influenced by GF2. GF2 reduced the mitochondrial membrane potential, basal mitochondrial respiratory rate, and ATP production capacity. Our results showed that GF2 downregulated the relative GSH/GSSG, intracellular NAD+ level, and GLRX expression, suggesting that GF2 may alter the intracellular redox balance that led to mitochondrial impairment. CONCLUSION: GF2 reduces mitochondrial membrane potential, inhibits cellular oxygen consumption, activates AMPK signaling, and induces cell death. Our study examined the potential vulnerability of mitochondrial activity in GBM, and this may hold therapeutic promise.

Effect of Aging on Homeostasis in the Soft Tissue of the Periodontium: A Narrative Review.

Aging is characterized by a progressive decline or loss of physiological functions, leading to increased susceptibility to disease or death. Several aging hallmarks, including genomic instability, cellular senescence, and mitochondrial dysfunction, have been suggested, which often lead to the numerous aging disorders. The periodontium, a complex structure surrounding and supporting the teeth, is composed of the gingiva, periodontal ligament, cementum, and alveolar bone. Supportive and protective roles of the periodontium are very critical to sustain life, but the periodontium undergoes morphological and physiological changes with age. In this review, we summarize the current knowledge of molecular and cellular physiological changes in the periodontium, by focusing on soft tissues including gingiva and periodontal ligament.

The MAO Inhibitor Tranylcypromine Alters LPS- and Aß-Mediated Neuroinflammatory Responses in Wild-type Mice and a Mouse Model of AD.

Monoamine oxidase (MAO) has been implicated in neuroinflammation, and therapies targeting MAO are of interest for neurodegenerative diseases. The small-molecule drug tranylcypromine, an inhibitor of MAO, is currently used as an antidepressant and in the treatment of cancer. However, whether tranylcypromine can regulate LPS- and/or Aß-induced neuroinflammation in the brain has not been well-studied. In the present study, we found that tranylcypromine selectively altered LPS-induced proinflammatory cytokine levels in BV2 microglial cells but not primary astrocytes. In addition, tranylcypromine modulated LPS-mediated TLR4/ERK/STAT3 signaling to alter neuroinflammatory responses in BV2 microglial cells. Importantly, tranylcypromine significantly reduced microglial activation as well as proinflammatory cytokine levels in LPS-injected wild-type mice. Moreover, injection of tranylcypromine in 5xFAD mice (a mouse model of AD) significantly decreased microglial activation but had smaller effects on astrocyte activation. Taken together, our results suggest that tranylcypromine can suppress LPS- and Aß-induced neuroinflammatory responses in vitro and in vivo.