Exogenous CLASP2 protein treatment enhances wound healing in vitro and in vivo

TNF-α drives bladder cancer metastasis via METTL3-mediated m6A modification to promote CLASP2/IQGAP1-dependent cytoskeleton remodeling

BACKGROUND

Bladder cancer (BCa) metastasis is a multi-step process triggered by cytoskeleton reorganization. However, the regulation mechanism of cytoskeleton reorganization in BCa remains ambiguous. This study elucidated the influence of tumor necrosis factor-alpha (TNF-α) in cytoskeleton remodeling during BCa metastasis and its possible mechanisms.

METHODS

Colony formation, scratch, transwell, and the nude mouse model were adopted to evaluate the growth and metastasis. Molecular expression was assessed by immunohistochemical staining, quantitative real-time PCR (qRT-PCR), and Western blotting. The N6-methyladenosine (m6A) level was detected by methylated RNA immunoprecipitation (MeRIP). Protein interaction was validated by Co-immunoprecipitation (Co-IP). Immunofluorescence staining was used to identify rearrangement of actin filament fibers (F-actin) and protein colocalization.

RESULTS

TNF-α facilitated cytoplasmic linker associated protein 2 (CLASP2) and methyltransferase like 3 (METTL3) expression in a dose (10-50 ng/mL)-dependent manner in BCa. CLASP2 high expression suggested a shorter overall survival of BCa patients. CLASP2 deficiency suppressed BCa cell proliferation, migration, and invasion via disrupting F-actin cytoskeleton. Mechanistically, TNF-α promoted METTL3-mediated m6A modification of CLASP2 to enhance CLASP2 mRNA stability. Moreover, CLASP2 directly interplayed with IQ motif containing GTPase activating protein 1 (IQGAP1) to regulate F-actin cytoskeleton remodeling. In vivo data demonstrated that inhibition of METTL3/CLASP2 axis delayed lung metastasis in nude mice.

CONCLUSION

TNF-α favors BCa cell metastasis, which involves METTL3-mediated m6A modification of CLASP2 that interacts with IQGAP1, thus leading to F-actin cytoskeleton remodeling. Our findings suggest targeting TNF-α/METTL3/CLASP2/IQGAP1 axis as a potential avenue for promising treatment for BCa.

Transcriptome Profile in the Mouse Brain of Hepatic Encephalopathy and Alzheimer's Disease

Hepatic encephalopathy (HE) is a chronic metabolic disease accompanied by neuropathological and neuropsychiatric features, including memory deficits, psychomotor dysfunction, depression, and anxiety. Alzheimer's disease (AD), the most common neurodegenerative disease, is characterized by tau hyperphosphorylation, excessive amyloid beta (Aβ) accumulation, the formation of fibrillary tangles, hippocampus atrophy, and neuroinflammation. Recent studies have suggested a positive correlation between HE and AD. Some studies reported that an impaired cholesterol pathway, abnormal bile acid secretion, excessive ammonia level, impaired Aβ clearance, astrocytic dysfunction, and abnormal γ-aminobutyric acid GABAergic neuronal signaling in HE may also be involved in AD pathology. However, the mechanisms and related genes involved in AD-like pathology in the HE brain are unclear. Thus, we compared the cortical transcriptome profile between an HE mouse model, bile duct ligation (BDL), and an AD mouse model, the 5×FAD. Our study showed that the expression of many genes implicated in HE is associated with neuronal dysfunction in AD mice. We found changes in various protein-coding RNAs, implicated in synapses, neurogenesis, neuron projection, neuron differentiation, and neurite outgrowth, and non-coding RNAs possibly associated with neuropathology. Our data provide an important resource for further studies to elucidate AD-like pathophysiology in HE patients.

Recent advances of the nanocomposite hydrogel as a local drug delivery for diabetic ulcers

Diabetic ulcer is a serious complication of diabetes. Compared with that of healthy people, the skin of patients with a diabetic ulcer is more easily damaged and difficult to heal. Without early intervention, the disease will become increasingly serious, often leading to amputation or even death. Most current treatment methods cannot achieve a good wound healing effect. Numerous studies have shown that a nanocomposite hydrogel serves as an ideal drug delivery method to promote the healing of a diabetic ulcer because of its better drug loading capacity and stability. Nanocomposite hydrogels can be loaded with one or more drugs for application to chronic ulcer wounds to promote rapid wound healing. Therefore, this paper reviews the latest progress of delivery systems based on nanocomposite hydrogels in promoting diabetic ulcer healing. Through a review of the recent literature, we put forward the shortcomings and improvement strategies of nanocomposite hydrogels in the treatment of diabetic ulcers.