The G‐protein‐coupled receptor 126 (GPR126) may play an important role in tumor development, although its role remains poorly understood. We found that GPR126 had higher expression in most colorectal cancer cell lines than in normal colon epithelial cell lines, and higher expression levels in colorectal cancer tissues than in normal adjacent colon tissues. GPR126 knockdown induced by shRNA inhibited cell viability and colony formation in HT‐29, HCT116, and LoVo cells, decreased BrdU incorporation into newly synthesized proliferating HT‐29 cells, led to an arrest of cell cycle progression at the G1 phase in HCT‐116 and HT‐29 cells, and suppressed tumorigenesis of HT‐29, HCT116, and LoVo cells in nude mouse xenograft models. GPR126 knockdown engendered decreased transcription and translation of histone deacetylase 2 (HDAC2), previously implicated in the activation of GLI1 and GLI2 in the Hedgehog signaling pathway. Ectopic expression of HDAC2 in GPR126‐silenced cells restored cell viability and proliferation, GLI2 luciferase reporter activity, partially recovered GLI2 expression, and reduced the cell cycle arrest. HDAC2 regulated GLI2 expression and, along with GLI2, it bound to the PTCH1 promoter, as evidenced by a chip assay with HT‐29 cells. Purmorphamine, a hedgehog agonist, largely restored the cell viability and expression of GLI2 proteins in GPR126‐silenced HT‐29 cells, whereas GANT61, a hedgehog inhibitor, further enhanced the GPR126 knockdown‐induced inhibitory effects. Our findings demonstrate that GPR126 regulates colorectal cancer cell proliferation by mediating the expression of HDAC2 and GLI2, therefore it may represent a suitable therapeutic target for colorectal cancer treatment.

Adhesion G protein-coupled receptors (aGPCRs) are the second largest diverse group within the GPCR superfamily, which play critical roles in many physiological and pathological processes through cell–cell and cell–extracellular matrix interactions. The adhesion GPCR Adgrg6, also known as GPR126, is one of the better-characterized aGPCRs. GPR126 was previously found to have critical developmental roles in Schwann cell maturation and its mediated myelination in the peripheral nervous system in both zebrafish and mammals. Current studies have extended our understanding of GPR126-mediated roles during development and in human diseases. In this review, we highlighted these recent advances in GPR126 in expression profile, molecular structure, ligand–receptor interactions, and associated physiological and pathological functions in development and diseases.

Precise, noninvasive drug delivery to small but important brain regions is challenging and highly desired given the brain’s inherent complexity and heterogeneous nature. Here, we report an approach utilizing focused ultrasound (FUS) combined with nanobubbles to successfully navigate this challenge. Compared to traditional microbubbles, nanobubbles exhibit superior acoustic properties. The nanobubbles, when exposed to FUS, induce a highly localized and reversible opening of the blood–brain barrier (BBB) with significantly enhanced precision (up to fourfolds compared to microbubbles, as measured by the precision loss metric). Repeated multitarget FUS-NB precisely delivers macromolecular human-derived anti-N-methyl-D-aspartate receptors monoclonal antibodies (HuMAbs) into the small brain region within a 2-h half-life window per opening. Fluorescence images confirm HuMAb retention in the brain parenchyma for at least 10 d postadministration. With this approach, we targeted the lateral habenula, a small but effective brain target for antidepressant treatments, and significantly alleviated depression-like symptoms at least 2 wk in a mouse model (tail suspension test/forced swim test: P < 0.01/0.05). Moreover, minimal red blood cell extravasation (0.9‱ affected area) was observed in the treated region after multiple FUS treatments, indicating the safety and tolerability of FUS-nanobubble-mediated BBB opening. The enhanced delivery precision, coupled with a favorable safety profile, positions our approach as a promising strategy for antibody therapy with significant clinical translation potential.

Mutations in the neuroblastoma amplified sequence (NBAS) gene correlate with infantile acute liver failure (ALF). Herein, we identified a novel NBAS mutation in a female infant diagnosed with recurrent ALF. Whole-exome and Sanger sequencing revealed that the proband carried a compound heterozygous mutation (c.938_939delGC and c.1342 T > C in NBAS). NBAS c.938_939delGC was presumed to encode a truncated protein without normal function, whereas NBAS c.1342 T > C encoded NBAS harboring the conserved Cys448 residue mutated to Arg448 (p.C448R). The proportion of CD4 + T cells decreased in the patient’s peripheral CD45 + cells, whereas that of CD8 + T cells increased. Moreover, upon transfecting the same amount of DNA expression vector (ectopic expression) encoding wild-type NBAS and p.C448R NBAS, the group transfected with the p.C448R NBAS-expressing vector expressed less NBAS mRNA and protein. Furthermore, ectopic expression of the same amount of p.C448R NBAS protein as the wild-type resulted in more intracellular reactive oxygen species and the induction of apoptosis and expression of marker proteins correlating with endoplasmic reticulum stress in more cultured cells. This study indicated that p.C448R NBAS has a function different from that of wild-type NBAS and that the p.C448R NBAS mutation potentially affects T-cell function and correlates with ALF.

Circadian rhythm disorders are common characteristics of neurodegenerative diseases. The pathological aggregation of transactive response DNA-binding protein 43 (TDP-43) is associated with multiple neurodegenerative diseases, such as amyotrophic lateral sclerosis. However, the relationship between TDP-43 and circadian rhythm remains unknown. Here, we found that TDP-43 is rhythmically expressed both in vivo and in vitro. TDP-43 knockdown affected the expression of circadian genes, including BMAL1, CLOCK, CRY1, and PER2, and impaired autonomous circadian wheel behavior, cognitive functions, and balance abilities in mice. Furthermore, TDP-43 knockdown induced aberrant splicing of ubiquitin-specific peptidase 13 (USP13) and blocked USP13 rhythmic expression, enhancing the ubiquitination of BMAL1. Meanwhile, TDP-43 knockdown altered the rhythmic expression of phospho-AMPKα (Thr172) and platelet-type phosphofructokinase (PFKP), which may change cellular glucose uptake and ATP production. Our findings further the understanding of the role of TDP-43 dysfunction in circadian rhythm disruption in neurodegenerative diseases and provide new mechanistic evidence supporting the interaction between circadian rhythm disruption and neurodegeneration.