The in vitro and in vivo anticancer activities of Antrodia salmonea through inhibition of metastasis and induction of ROS-mediated apoptotic and autophagic cell death in human glioblastoma cells

Naringin Induces ROS-Stimulated G1 Cell-Cycle Arrest and Apoptosis in Nasopharyngeal Carcinoma Cells

Naringin, a bioflavonoid compound from grapefruit or citrus, exerts anticancer activities on cervical, thyroid, colon, brain, liver, lung, thyroid, and breast cancers. The present investigation addressed exploring the anticancer effects of naringin on nasopharyngeal carcinoma (NPC) cells. Naringin exhibits a cytotoxic effect on NPC-TW 039 and NPC-TW 076 cells with IC50 372/328 and 394/307 μM for 24 or 48 h, respectively, while causing little toxicity toward normal gingival epithelial (SG) cells (>500/500 μM). We established that naringin triggered G1 arrest is achieved by suppressing cyclin D1, cyclin A, and CDK2, and upregulating p21 protein in NPC cells. Exposure of NPC cells to naringin caused a series of events leading to apoptosis including morphology change (cell shrinkage and membrane blebbing) and chromatin condensation. Annexin V and PI staining indicated that naringin treatment promotes necrosis and late apoptosis in NPC cells. DiOC6 staining showed a decline in the mitochondrial membrane potential by naringin treatment, which was followed with cytochrome c release, Apaf-1/caspase-9/-3 activation, PARP cleavage, and EndoG expression in NPC cells. Naringin upregulated proapoptotic Bax and decreased antiapoptotic Bcl-xL expression, and dysregulated Bax/Bcl-xL ratio in NPC cells. Notably, naringin enhanced death receptor-related t-Bid expression. Furthermore, an increased Ca2+ release by naringin treatment which instigated endoplasmic reticulum stress-associated apoptosis through increased IRE1, ATF-6, GRP78, GADD153, and caspase-12 expression in NPC cells. In addition, naringin triggers ROS production, and inhibition of naringin-induced ROS generation by antioxidant N-acetylcysteine resulted in the prevention of G1 arrest and apoptosis in NPC cells. Naringin-induced ROS-mediated G1 arrest and mitochondrial-, death receptor-, and endoplasmic reticulum stress-mediated apoptosis may be a promising strategy for treating NPC.

CK1δ/ε inhibition induces ULK1-mediated autophagy in tumorigenesis

INTRODUCTION

Autophagy is an important mechanism of cell homeostasis maintenance. As essential serine/threonine-protein kinases, casein kinase I family members affect tumorigenesis by regulating a variety of cellular progression. However, the mechanism by which they regulate autophagy remains unclear.

MATERIALS AND METHODS

We silenced CK1δ/ε in cancer cells and observed cell morphology, the expression of autophagy-related genes, and its impact on cancer cell growth and viability. By inhibiting CK1δ/ε-induced upregulation of autophagy genes, we profiled the regulatory mechanism of CK1δ/ε on autophagy and cancer cell growth. The impact of CK1δ/ε inhibition on tumor cell growth was also assessed in vivo.

RESULTS

Here, we found that CK1δ/ε played an important role in ULK1-mediated autophagy regulation in both lung cancer and melanoma cells. Mechanically, silencing CK1δ/ε increased ULK1 expression with enhanced autophagic flux and suppressed cancer cell proliferation, while ULK1 knockdown blocked the activation of autophagy caused by CK1δ/ε inhibition. By silencing CK1δ/ε in syngeneic mouse model bearing LLC1 murine lung cancer cells in vivo, we observed tumor growth suppression mediated by CK1δ/ε inhibition.

CONCLUSION

Our results provide evidence for the role of CK1δ/ε in the regulation of tumorigenesis via the ULK1-mediated autophagy, and also suggest the impact of CK1δ/ε inhibition on tumor growth and its significance as a potential therapeutic target.

Antrodia salmonea suppresses epithelial-mesenchymal transition/metastasis and Warburg effects by inhibiting Twist and HIF-1α expression in Twist-overexpressing head and neck squamous cell carcinoma cells

ETHNOPHARMACOLOGICAL RELEVANCE

Antrodia salmonea (AS), linked to the genus Taiwanofungus, is a medicinal fungus, and exhibits anti-inflammatory, anti-oxidant, and tumor inhibiting properties.

AIM OF THE STUDY

In this study, we investigated the metabolic reprogramming and anti-metastasis/epithelial-mesenchymal transition (EMT) effects of AS exposure in Twist-overexpressing head and neck squamous cell carcinoma (HNSCC, OECM-1 and FaDu-Twist) cells.

MATERIALS AND METHODS

MTT assay, Western blot, migration/invasion assay, immunofluorescence, glucose uptake assay, lactate assay, oxygen consumption rate (OCR)/Extracellular acidification rate (ECAR) assay, Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS), and qRT-PCR experimental techniques were used to evaluate the therapeutic potential of AS treatment in HNSCC cells.

RESULTS

This study showed that AS exhibits anti-EMT and anti-metastatic effects as well as metabolic reprogramming in Twist-overexpressing HNSCC cells. AS exposure inhibited Twist and hypoxia-inducible factor-1α (HIF-1α) protein and/or mRNA expression in Twist-overexpressing OECM-1 and FaDu-Twist cells. AS markedly suppressed EMT by enhancing the expression of E-cadherin; while the N-cadherin was suppressed. Furthermore, glucose uptake and lactate accumulation, together with HIF-1α-regulated glycolysis genes were diminished by AS in OECM-1 cells. AS decreased the ECAR, and enhanced the OCR together with basal respiration, ATP production, maximal respiration, and spare respiratory capacity under normoxia and hypoxia (CoCl2) in OECM-1 cells. There was a marked reduction in the level of glycolytic intermediate's; while TCA cycle metabolites were increased by AS treatment in OECM-1 cells.

CONCLUSIONS

We concluded that AS treatment suppresses EMT/metastasis and Warburg effects through Twist and HIF-1α inhibition in Twist-overexpressing HNSCC cells.

Inhibition of miR-144-3p/FOXO1 Attenuates Diabetic Keratopathy Via Modulating Autophagy and Apoptosis

Purpose

Diabetic keratopathy (DK) is a vision-threatening disease that occurs in people with diabetes. Mounting evidence indicates that microRNAs (miRNAs) are indispensable in nerve regeneration within DK. Herein, the role of miRNAs associated with DK, especially focusing on autophagy and apoptosis regulation, was investigated.

Methods

To identify differentially expressed miRNAs, we performed miRNA sequencing on trigeminal ganglion (TG) tissues derived from streptozotocin-induced type 1 diabetic mellitus (T1DM) and normal mice. MiR-144-3p was chosen for the subsequent experiments. To explore the regulatory role of miR-144-3p in DK, miRNA antagomir was utilized to inhibit miR-144-3p expression. Bioinformatic tools were used to predict the target genes of miR-144-3p, and a dual-luciferase reporter assay was then applied for validation. Autophagy and apoptosis activities were measured utilizing TUNEL staining, immunofluorescence staining, and Western blotting.

Results

Overall, 56 differentially expressed miRNAs were detected in diabetic versus control mice. In the diabetic mouse TG tissue, miR-144-3p expression was aberrantly enhanced, whereas decreasing its expression contributed to improved diabetic corneal re-epithelialization and nerve regeneration. Fork-head Box O1 (FOXO1) was validated as a target gene of miR-144-3p. Overexpression of FOXO1 could prevent both inadequate autophagy and excessive apoptosis in DK. Consistently, a specific miR-144-3p inhibition enhanced autophagy and prevented apoptosis in DK.

Conclusions

In this study, our research confirmed the target binding relationship between miR-144-3p and FOXO1. Inhibiting miR-144-3p might modulate autophagy and apoptosis, which could generate positive outcomes for corneal nerves via targeting FOXO1 in DK.