Stathmin 1 (STMN1) is a microtubule-binding cytoplasmic phosphoprotein that promotes microtubule depolymerization or inhibits microtubule assembly, thereby regulating cytoskeletal organization and cell cycle progression. STMN1 is upregulated in a variety of malignant tumors, where it drives proliferation, invasion, metastasis, and angiogenesis through classic pathways such as nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), and ferroptosis. STMN1 can also modulate the function of immune cells, thereby influencing antitumor immunity. Clinical data show that its high expression correlates positively with tumor drug resistance and poor prognosis, suggesting that STMN1 has potential as a tumor biomarker and therapeutic molecular target with important clinical significance.
Humans ; Stathmin/metabolism* ; Neoplasms/genetics* ; Biomarkers, Tumor/metabolism* ; NF-kappa B/metabolism* ; Cell Proliferation ; Drug Resistance, Neoplasm

We studied the aggregation of a recombinant engineering antibody (chA21). Anti-ErbB2 antibody chA21 was produced by fusing single-chain Fv (scFv) with human IgG1 Fc fragment, and it was proved to be a drug candidate for cancer therapy. We characterized the aggregation of chA21 by high performance sized-exclusive chromatography (HPSEC), dynamic light scattering (DLS), SDS-PAGE, indirect ELISA assay, and compared the influence of temperature and additive on the level of aggregation and binding activity. Conformation changes of different levels of aggregation were also analyzed via circular dichroism (CD). Finally, we analyzed which part of chA21 was involved in aggregation by cleaving it into scFv and Fc fragments. The results showed that chA21 could form aggregates in the storage solution. The aggregates interacted through non-covalent bonds and remained binding activity. Temperature and additive could slightly affect the level of aggregation and binding activity, while the conformations of chA21 were stable. Aggregation propensity of scFv fragment was almost same as chA21, indicating that scFv may be the major part to form the aggregates. The research on aggregation may be helpful to develop a suitable formulation for chA21 clinical application as well as provide direction for future antibody design and reconstruction.
Antibodies ; chemistry ; metabolism ; Humans ; Immunoglobulin Fc Fragments ; chemistry ; metabolism ; Immunoglobulin Variable Region ; chemistry ; metabolism ; Protein Conformation ; Protein Engineering ; methods ; Receptor Aggregation ; immunology ; Receptor, ErbB-2 ; chemistry ; immunology ; Recombinant Proteins ; biosynthesis ; chemistry ; genetics ; immunology