Technical Articles

This article focuses on the molecular characteristics and immunoregulatory functions of programmed cell death protein 1 (PD-1) and its ligand PD-L1, systematically elaborating on the domain composition of both as type I transmembrane proteins and the protein-protein interaction interface formed by their extracellular regions, analyzing the expression characteristics of PD-1 induced after T cell activation and PD-L1 under the multiple regulation of inflammatory cytokines and non-inflammatory factors, and exploring the dual role of this pathway in the maintenance of physiological immune tolerance and tumor immune evasion, as well as its structural basis as a therapeutic target for immune checkpoint therapy.

This article focuses on the molecular localization and signal transduction mechanisms of the epidermal growth factor receptor (EGFR), systematically elaborating its structural characteristics as a transmembrane glycoprotein and its chromosomal localization as a member of the HER family, analyzing the molecular process by which six ligands bind to the EGFR extracellular domain to induce dimerization and tyrosine kinase activation, and exploring the cascade logic through which activated EGFR transmits proliferation and anti-apoptotic signals to the nucleus via downstream pathways such as PI3K-AKT-mTOR and Ras-Raf-MEK-ERK1/2.

This article focuses on the molecular characteristics and clinical pathogenic mechanisms of human epidermal growth factor receptor 2 (HER2), systematically elaborating on its receptor properties as a HER family member that has no known ligand and relies on dimerization for activation, analyzing the differences between two types of pathogenic mechanisms—protein overexpression caused by HER2 gene amplification and HER2 mutations (including exon 20 insertion mutations)—in terms of cancer type distribution and molecular consequences, and exploring the logic of targeted therapeutic strategies based on mechanism-based classification.

This article focuses on the molecular structure, expression regulation, and immune functions of B7-H3 (CD276), systematically elaborating on the separation phenomenon between its gene encoding and widespread transcript distribution as a type I transmembrane protein of the immunoglobulin superfamily and its highly restricted protein expression, analyzing its expression characteristics on immune cells and its bidirectional regulatory effects on NK cells, cytotoxic T cells, and conventional T cells, and exploring its association with overexpression and poor prognosis in solid tumors such as bladder cancer, prostate cancer, and melanoma, as well as diverse therapeutic strategies including monoclonal antibodies, bispecific antibodies, ADCs, and CAR-T.

This article focuses on the molecular composition and mechanism of action of the PD-1/PD-L1 immune checkpoint pathway, systematically elaborating the immune evasion pathway by which tumor cells inhibit T cell killing function through the binding of PD-L1 to PD-1 on the T cell surface, analyzing the therapeutic principle by which PD-1 antibodies block this ligand-receptor interaction to restore T cell antitumor activity, and exploring the biological basis for this pathway being the most closely watched target in current tumor immunotherapy.

This article focuses on the protein structure, signaling activation mechanisms, and kinase domain mutation spectrum of the epidermal growth factor receptor (EGFR), systematically elaborating its functional architecture composed of the extracellular ligand-binding domain, transmembrane domain, intracellular tyrosine kinase domain, and ATP-binding site, analyzing the molecular differences between ligand-dependent dimerization activation under normal physiological conditions and ligand-independent constitutive activation under mutant states, and exploring the functional classification of various mutations in exons 18 to 21 and their determining role in targeted therapeutic strategies.

This article focuses on the protein structure and signaling regulation functions of human epidermal growth factor receptor 2 (HER2), systematically elaborating its composition as an EGFR family transmembrane glycoprotein comprising extracellular, transmembrane, and intracellular domains, as well as its activation characteristics in the absence of known ligands. It analyzes the differential downstream signals driven by HER2 forming heterodimers with family members across different cancer types, and explores the clinical association of HER2 overexpression with tumor aggressiveness and poor prognosis, along with targeted therapeutic strategies.

This article focuses on the molecular structure, expression distribution, and tumor immunological functions of B7-H3 (CD276), systematically elaborating its composition as a type I transmembrane protein with extracellular immunoglobulin domains and the characteristics of its intracellular region lacking clear signaling motifs, analyzing its distribution pattern of widespread mRNA expression but relatively restricted protein expression as well as its association with overexpression and poor prognosis in multiple tumors, and exploring the development logic of therapeutic strategies targeting B7-H3 under the condition that its receptor has not yet been clearly identified.

This article focuses on the molecular characteristics of the PD-1/PD-L1 immune checkpoint pathway and the mechanisms of action of its inhibitors, systematically elaborating the balance between T cell activation signals and inhibitory signals as well as the molecular pathways by which tumor cells utilize PD-L1 to achieve immune evasion, analyzing the differences between PD-1 and PD-L1 in terms of expressing cell types and expression regulatory conditions, and exploring the systematic differences between PD-1 inhibitors and PD-L1 inhibitors in antibody structure, mechanisms of action, and incidence of adverse reactions.

This article focuses on the molecular structure of the epidermal growth factor receptor (EGFR) protein and the clinical significance of exon 20 mutations, systematically elaborating on the structural organization of the EGFR kinase domain and the conformational change mechanisms underlying exon 20 mutations, analyzing the essential differences in structure-function relationships between exon 20 insertion mutations and point mutations, and exploring the sensitivity patterns of different mutation types to various targeted drugs as well as the corresponding therapeutic strategies.