The Myc/Max/Mad network regulates cell proliferation, differentiation, and apoptosis through bHLH-ZIP domain-mediated dimerization and DNA binding. Max serves as a central hub, forming homodimers or heterodimers with Myc and Mad families, which exert opposing transcriptional effects. The Myc family (c-Myc, N-Myc, L-Myc) shows distinct expression and amplification patterns in cancers, including mutually exclusive amplifications in neuroblastoma (N-Myc) and small cell lung cancer (L-Myc). Phosphorylation of c-Myc at Ser62 and Thr58 controls its proteasomal degradation. Key antibodies and references are also summarized.

The reagent contains the water-soluble tetrazolium salt WST-8 [chemical name: 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium monosodium salt]. Under the mediation of an electron carrier—1-methoxy-5-methylphenazinium methylsulfate (1-Methoxy PMS)—this salt is reduced by mitochondrial dehydrogenases within viable cells into a highly water-soluble yellow formazan dye. The amount of formazan produced is directly proportional to the number of viable cells. By measuring the optical density (OD) value at a wavelength of 450 nm using a microplate reader, one can indirectly quantify the number of viable cells.

Vesicle trafficking is an integral cellular process and the associated proteins involved also play major roles in other signaling pathways. Caveolins are involved in diverse biological functions including vesicular trafficking, cholesterol homeostasis, cell adhesion, apoptosis, and are also indicated in neurodegenerative disease (1). It is believed that caveolins serve as scaffolding proteins for the integration of signal transduction. Phosphorylation at Tyr14 is essential for caveolin association with SH2 or PTB domain-containing adaptor proteins, such as GRB7 (2-4).

The cytoskeleton consists of three types of cytosolic fibers: microfilaments (actin filaments), intermediate filaments, and microtubules. Major types of intermediate filaments are distinguished by their cell-specific expression: cytokeratins (epithelial cells), glial fibrillary acidic protein (GFAP) (glial cells), desmin (skeletal, visceral, and certain vascular smooth muscle cells), vimentin (mesenchyme origin), and neurofilaments (neurons).

The Wnt family includes several secreted glycoproteins that play important roles in animal development. β-catenin is a key downstream effector of the Wnt signaling pathway that research studies have shown is implicated in early embryonic development and tumorigenesis in vertebrates (1-3). Following binding of Wnt family proteins to the Frizzled receptor, β-catenin translocates to the nucleus where it interacts with LEF1 and TCF1 to activate canonical targets (4). Accepted canonical targets include CD44, cyclin D1, c-Jun, c-Myc, Met, and MMP-7 (5-11).

This study aimed to systematically analyze the immune microenvironment of lung cancer brain metastasis under different genetic backgrounds and TKI treatment states using single-cell transcriptome sequencing and multiplex immunohistochemistry, confirm CTLA4 as a key target to overcome TKI resistance, and demonstrate in mouse models of EGFR-sensitive and resistant mutant lung cancer brain metastasis that sequential use of EGFR-TKI and CTLA4 blockade is significantly more effective than TKI monotherapy or TKI combined with PD-1 blockade, providing a novel therapeutic strategy for overcoming TKI resistance in lung cancer brain metastasis.

This study, published in Nature Communications and led by the Zhong Qing team at Shanghai Jiao Tong University School of Medicine, for the first time fully elucidates the molecular mechanism of Necrosis by Sodium Overload (NECSO): Na⁺ is not a passive consequence of cell death, but triggers cell death by disrupting mitochondrial energy metabolism. Na⁺ acts as an active initiator of necrosis, rather than merely a late participant in osmotic disruption.