Multiple myeloma (MM) is a hematologic malignancy characterized by clonal proliferation of plasma cells within the bone marrow, with pathological features including abnormal secretion of monoclonal immunoglobulins, osteolytic bone disease, and multi-organ dysfunction. Despite significant advancements in therapeutic approaches that have markedly extended patient survival, primary drug resistance and relapse remain major obstacles to clinical cure. The pathogenesis and progression of MM are intricately regulated by the bone marrow microenvironment (BMME), a dynamic network composed of diverse cellular and non-cellular components. The BMME not only supports the survival and proliferation of MM cells but also plays a pivotal role in disease progression by modulating bone metabolic homeostasis, mediating immune escape, and promoting drug resistance. In recent years, groundbreaking therapeutic strategies targeting the BMME have emerged, including immunomodulatory drugs, bispecific antibodies, CAR T-cell therapies, and microenvironment-modulating agents. These approaches have significantly improved objective response rates and survival outcomes in relapsed/refractory MM by disrupting cytokine signaling, reprogramming the immunosuppressive microenvironment, or inhibiting tumor-stromal interactions. However, challenges such as drug resistance, treatment-related toxicity, and tumor heterogeneity persist in clinical practice. This review systematically delineates the roles of BMME components in MM pathogenesis, analyzes the molecular mechanisms underlying MM cell-BMME interactions, and explores innovative strategies to enhance therapeutic efficacy and prognosis through targeted modulation of the BMME. These insights provide a foundation for developing novel therapeutic paradigms aimed at overcoming current limitations in MM treatment.
Multiple myeloma (MM) is a hematologic malignancy originating from plasma cells in the bone marrow. In recent years, the use of novel drugs and hematopoietic stem cell transplantation (HSCT) has significantly improved the prognosis of MM patients. However, MM remains challenging to cure and is prone to relapse and resistance. For patients with relapsed/refractory multiple myeloma (RRMM), there is an urgent need to explore novel therapeutic approaches. Bispecific antibodies (BsAbs) are a promising class of immunotherapeutics that functions by simultaneously binding to tumor cell antigens and endogenous effector cells, thereby forming an immunological synapse. This interaction facilitates the activation of effector cells, leading to the targeted lysis of tumor cells. Numerous clinical studies have demonstrated the significant efficacy of BsAbs, either as monotherapy or in combination with other treatment regimens, in patients with RRMM. This article summarizes the mechanisms of action, efficacy, and safety of BsAbs, and discusses optimal sequencing strategies in immunotherapy, aiming to provide new perspectives for the treatment of MM.
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by impairments in social interaction, communication, and repetitive behaviors. Accumulating evidence suggests that neuroimmune inflammatory responses may contribute to the pathogenesis of ASD. Within the central nervous system, microglia, as the key innate immune cells, play a pivotal role in shaping the neuroimmune inflammatory microenvironment. This review systematically synthesizes findings regarding alterations in microglial number and morphology across two major categories of ASD mouse models, considering both genetic and environmental dimensions. Specifically, it examines changes in dendritic spine density and neurotransmission function in gene mutation-induced models and environmentally triggered models, such as maternal immune activation models. Furthermore, this article highlights comparative analyses of shared mechanisms, including the interleukin-17 receptor A signaling pathway and the mammalian target of rapamycin signaling pathway, between MIA models and genetically induced BTBR T+Itpr3tf/J mouse models. Building on these insights, the review elaborates on cytokine dysregulation in abnormally activated microglia, mitochondrial oxidative phosphorylation dysfunction, and elevated reactive oxygen species levels within ASD mouse brains, elucidating their implications for cellular function. Finally, the article summarizes how microglia influence neurodevelopment through neurogenesis and synaptic formation and function, exploring potential pathways underlying autism-like behavioral phenotypes and identifying novel therapeutic targets for clinical ASD intervention.
Nucleic acid detection technology has been widely applied in fields such as pathogen detection due to its characteristics of rapidity, sensitivity, and specificity. With the numerous nucleic acid markers related to diseases, the demand for multiplex nucleic acid detection is gradually increasing. Multiplex polymerase chain reaction (PCR) can simultaneously amplify multiple targets, but there are problems such as easy contamination when opening the tube during the analysis process after amplification and high technical requirements. With the continuous advancement of detection technology, a series of simple, reliable single-tube multiplex PCR detection technologies that do not require opening the tube have emerged successively. A common technology is the single-closed tube multiplex PCR detection method based on fluorescent probes, which mainly uses different fluorescent labels to distinguish multiple targets. Combined with different specific enzymatic digestion reactions, it can achieve multiplex detection of rare tumor mutations and single nucleotide-specific genotyping. In addition, the monochromatic melting curve analysis method based on differences in melting temperatures enables parallel detection of multiple targets within a single fluorescence channel. When performed within multiple fluorescence channels, it is called the multicolor melting curve analysis method, which can increase the number of detected targets to dozens, greatly breaking through the limitation of the number of fluorescence channels on the multiplexity of detection. At the same time, the fluorescence coding method using different combinations of fluorescent labels also provides new ideas for single-closed tube multiplex PCR detection. These include encoding the sequence of signals generated by different fluorescent labels corresponding to the same target, using a combination of two fluorescent labels to identify specific targets, and controlling the amplitude of fluorescent signals of different targets, all of which can also improve the multiplexity of detection.This article summarizes and prospects the research progress of single-closed tube multiplex PCR detection technology in recent years from multiple dimensions such as principles, applications, and the advantages and disadvantages of the methods, providing valuable references for subsequent scientific research exploration and application.
tRNA is one of the RNA molecules with the most diverse post-transcriptional modifications. It not only functions as an adaptor molecule transporting amino acids during translation but also relies on its extensive post-transcriptional modifications to regulate gene expression, thereby influencing numerous biological processes. These modifications are dynamically regulated by tRNA methyltransferases and demethylases, which collaboratively maintain a balance—the former catalyze methyl group addition, while the latter remove methyl groups, ensuring reversible control. Mutations or dysregulation of these enzymes are closely associated with tumorigenesis and other diseases, constituting a major research focus. They promote tumor progression through two distinct pathways: cytoplasmic tRNA (ctRNA) methylation enhances the translation of oncogenes, whereas mitochondrial tRNA (mtRNA) methylation optimizes mitochondrial protein synthesis to reprogram energy metabolism. From the dual dimensions of"enzyme supply" and"energy provision", tRNA methylation establishes a material foundation for tumor cell growth and directly contributes to cell cycle dysregulation. The cell cycle, an orderly process governing cell division, is tightly controlled by checkpoint proteins to guarantee accurate genetic information transmission. Notably, aberrant cell cycle activation is not only a hallmark of cancer but also a pivotal therapeutic target. tRNA methyltransferases and demethylases exert multidimensional control over both cell cycle progression and metabolic adaptation. Elucidating the mechanisms underlying tRNA modification mediated cell cycle regulation will not only accelerate the discovery of novel therapeutic targets but may also overcome the constraints of conventional cell cycle targeted therapies. Within this context, we systematically review the molecular mechanisms by which tRNA methylation-modifying enzymes regulate the cell cycle, with an emphasis on their translational potential.
Premature ovarian insufficiency (POI), also known as premature ovarian failure (POF), is one of the major causes of female infertility. Its incidence has been increasing year by year, seriously affecting women’s reproductive health and becoming an increasingly serious public health problem worldwide. The pathogenesis of POI is complex and may be related to genetic, immune and environmental factors, but in recent years, oxidative stress (OS) has received widespread attention as a key factor that can affect the function of ovarian granulosa cells (GCs), which can lead to the occurrence of POI. Reactive oxygen species (ROS) regulate the proliferation, survival and apoptosis of GCs through multiple signaling pathways, such as PI3K-Akt, MAPK, TGF-β/Smad, Notch, etc. AMPK and mitochondrial autophagy play important roles in attenuating the ROS damage and protecting the ovarian function. Excessive ROS disrupts the autophagy and lysosomal functions, leading to the accumulation of intracellular waste products, thus affecting the physiological function and endocrine stability of GCs. In addition, OS can increase the risk of POI by affecting hormone synthesis and disrupting the function of GCs, leading to an imbalance in estrogen and progesterone levels. Herein we review the mechanism of OS in POI, explore how OS affects ovarian decline through the regulation of signaling pathways and cellular functions, and provide a theoretical basis for the clinical treatment of POI, which in turn provides new research ideas for its early diagnosis and prevention.
Pancreatic cancer is a malignant tumor with a very poor prognosis, characterized by early metastasis and high invasiveness, and is unresponsive to traditional treatments like chemotherapy and radiotherapy. In recent years, the study of metabolic products has become a new hotspot in pancreatic cancer research, showing that the metabolic reprogramming of tumor cells is a key factor for their growth and proliferation, and that regulatory factors of metabolic pathways may serve as new therapeutic targets. Metabolic reprogramming primarily manifests as alterations in three major nutrient metabolic pathway and oxidative phosphorylation processes. Additionally, the tumor microenvironment of pancreatic cancer exhibits unique metabolic features. Mechanistic studies are actively underway, and future research may focus on integrating omics, artificial intelligence, and other novel research techniques to further explore how metabolic changes drive the development of pancreatic cancer and to improve treatment strategies, including the development of targeted drugs and metabolomics-based diagnostic tools.
Gefitinib, a first-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), exerts significant therapeutic efficacy in the treatment of non-small cell lung cancer (NSCLC) by selectively targeting mutant forms of EGFR. However, the development of acquired resistance significantly limits its long-term clinical benefits. Cell division cycle 20 (CDC20), a key regulator of cell cycle progression, has been implicated in the tumorigenesis and progression of various malignancies. Nevertheless, its role and underlying regulatory mechanisms in the acquisition of drug resistance in NSCLC remain largely unexplored. This study aimed to elucidate the molecular mechanisms by which CDC20 contributes to gefitinib resistance in NSCLC. Gefitinib-resistant cell lines, HCC827/GR (IC50 0.05 ± 0.01 μmol/L vs 36.24 ± 6.21 μmol/L) and PC9/GR (IC50 0.02 ± 0.01 μmol/L vs 25.36 ± 5.57 μmol/L), were established through stepwise drug induction, exhibiting markedly increased IC50 values compared to their parental counterparts. Bioinformatics analysis revealed that the transcriptional level of CDC20 is significantly upregulated in lung cancer tissues and is associated with poor patient prognosis. Western blotting analysis confirmed elevated CDC20 protein levels in the resistant HCC827/GR and PC9/GR cells relative to the parental HCC827 and PC9 cells. To further investigate the functional role of CDC20 in NSCLC gefitinib resistance, CDC20 was knocked out using CRISPR/Cas9 technology. This genetic intervention significantly restored gefitinib sensitivity in resistant cells (IC50 37.08 ± 6.15 μmol/L vs 10.49 ± 1.83 μmol/L, 7.23 ± 1.55 μmol/L), while concurrently promoting apoptosis and inducing G2/M phase cell cycle arrest. Conversely, CDC20 overexpression decreased drug sensitivity in parental cells and notably attenuated gefitinib-induced apoptosis and cell cycle arrest. Mechanistically, CDC20 depletion was found to inhibit activation of the PI3K/Akt/mTOR signaling pathway, upregulate pro-apoptotic proteins such as cleaved-Caspase 3 and Bax, and downregulate the anti-apoptotic protein Bcl-2. Collectively, these findings demonstrate that CDC20 mediates gefitinib resistance in NSCLC through modulation of the PI3K/Akt/mTOR signaling pathway, thereby identifying CDC20 as a potential therapeutic target for overcoming resistance to EGFR-targeted therapies.
Progressive symmetric erythrokeratodermia (PSEK) is a rare hereditary skin disease characterized by symmetrical erythema, hyperkeratosis and multiorgan lesions. Its clinical phenotypes are highly heterogeneous and may be accompanied by symptoms such as thrombocytopenia, which can be fatal in severe cases. The genotype-phenotype association mechanism of PSEK is extremely complex. Currently, it is known that mutations in multiple genes such as GJB3, KDSR, and KRT83 can cause the disease. Among them, 3-ketodihydrosphingosine reductase (KDSR) has been found to harbor nearly 20 clinical mutations. These mutations interfere with the de novo ceramide synthesis pathway, disrupt the homeostasis of the skin barrier, and cause platelet production disorders and multi-organ lesions, making it a current research hotspot in the molecular mechanism of PSEK. The pathogenic mutations of KDSR are widely and uniformly distributed throughout the entire protein, rather than being limited to the traditionally recognized active center, suggesting that the impairment of the KDSR enzymatic activity is not the only cause of PSEK. In view of this, this study selected four typical mutants of KDSR (KDSRQG55-56R, KDSRF138C, KDSRY186F, KDSRG182S), and first used recombinant expression technology to prepare pure and homogeneous mutant proteins. Subsequently, thermal stability experiments as well as oligomerization analysis were conducted on these four mutant proteins. The results showed that the Tm values of the four mutants were significantly lower than that of the wild type. Particularly, KDSRF138C and KDSRQG55-56R were nearly completely denatured at physiological temperature. This result was perfectly consistent with the further Rosetta energy analysis. In conclusion, this study took several pathological mutations of the PSEK pathogenic factor KDSR as the research object and discovered that the conformational stability of KDSR might be closely related to the occurrence of PSEK pathogenicity, indicating that the imbalance of conformational homeostasis is very likely to be one of the common contributing factors of many genetic diseases, including PSEK. This provides a new theoretical basis and reference for explaining the molecular mechanism of genotype-phenotype heterogeneity in many genetic diseases.
This study systematically investigated the molecular mechanisms underlying the involvement of mesoderm development-associated genes in melanoma progression through integrated bioinformatics analysis and experimental validation. Utilizing the GSVA (gene set variation analysis) algorithm to perform enrichment analysis of 7 752 biological functions in 406 skin cutaneous melanoma (SKCM) cases, we identified for the first time the significant activation of mesoderm development pathways during SKCM pathogenesis. Four core regulatory genes (SMAD4, NODAL, BMPR1A, and ZFP36L1) were screened using LASSO-COX regression analysis and a prognostic risk-scoring system was established. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed predominant enrichment of these genes in mRNA metabolic processes and TGF-β signaling pathways. Experimental validation through Quantitative Polymerase Chain Reaction (qPCR), Western blotting, and immunohistochemistry (IHC) demonstrated that: (1) Downregulation of SMAD4 and BMPR1A in tumor tissues was significantly correlated with poor prognosis (P<0.05); (2) NODAL promoted tumor invasion and metastasis by regulating epithelial-mesenchymal transition (EMT); (3) High ZFP36L1 expression was associated with enhanced chemotherapy sensitivity. Further analyses revealed significant correlations between core gene expression levels and tumor immune infiltration characteristics as well as immune checkpoint molecules. By integrating multi-omics analysis with experimental validation, this study elucidates the critical roles of mesoderm development-associated genes in SKCM progression, particularly clarifying the molecular mechanisms through which SMAD4/NODAL/BMPR1A/ZFP36L1 influence tumor biological behaviors via immune microenvironment regulation and EMT processes. These findings provide novel theoretical foundations for molecular subtyping and targeted therapy in melanoma.
Programmed cell death protein 1 (PD-1) and its ligand, programmed cell death 1 ligand 1 (PD-L1), represent a pair of prototypical immune checkpoint that plays a critical role in tumor immune evasion. However, the development of targeted therapeutics against these two proteins is limited by their low levels and high glycosylation modifications in eukaryotic cells. In this study, we designed two functional but truncated variants of PD-1 (PD-133-150) and PD-L1 (PD-L119-239); and subcloned them into eukaryotic expression vectors using golden gate assembly technology. Using these vectors, we achieved high level yields of these two proteins in transiently-transfected HEK-293T cells. After one-step affinity purification, the yields of PD-133-150 and PD-L119-239 proteins reached 5mg and 3mg per liter of cell culture medium, with over 95% purity. Using biolayer interferometry and flow cytometry analysis, we determined the binding kinetics, equilibrium constants, and the cellular binding activities of these proteins. Compared with the PD-1 extracellular domain expressed in insect or E. coli cells, the PD-133-150 purified from HEK-293T cells has a 24-fold and a 50-fold increase in its binding affinity to PD-L1. In addition, the dissociation rate of the binding decreased to less than 1/400th of the original rate. Thus, we speculate that N-glycosylation could modulate the PD-1/PD-L1 interactions. Together, we established an effective eukaryotic expression and purification platform for functional characterization of PD-133-150/PD-L119-239 interactions, thereby providing high-quality molecular tools for PD-1/PD-L1 antibody screening and immune checkpoint research.
SHI Chao, YE Zhao-Yang, XU Fei , DU Xiang-Ning, CHEN Zhang-Xin, GU Ming-Yue, DENG Jie, WANG Wei , LIU Liang-Yu , WANG Mei-Ying , SU Xiao-Dong , LIU He-Li , SHANG Ming-Ying , HUANG Li-Xin, CHANG Zhen-Zhan
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits. Isoflavone synthase (IFS) is a membrane-associated cytochrome P450 enzyme (CYP450) which carries out the unique aryl-ring migration and hydroxylation. So far, few crystal structures of plant P450s have been obtained. We determined the crystal structure of IFS from Medicago truncatula at 1.9 by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study. The structure of IFS complexed with imidazole exhibits the helix Iα-loop-helix Iβ motif which corresponds to helix I of otherP450s. Compared with structures of common P450s, IFS/imidazole structure contains an extra domain, i.e., the γ-domain. The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another. The plane of heme group makes an angle of approximately 40° with the helix Iα-loop-helix Iβ motif. Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recognition. Phe-301, Ser-303 and Gly-305 from the helix Iα-loop-helix Iβ motif may play important roles in the aryl-ring migration. These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.
Aberrant expression of Colgalt1 is closely associated with tumorigenesis and tumor progression; however, the mechanism by which it regulates macrophages to influence tumor development remains poorly understood. This study aimed to establish a macrophage-specific Colgalt1 gene knockout mouse model to delve into the mechanisms through which Colgalt1 modulates macrophage function and subsequently affects the occurrence and progression of tumor-related diseases. Initially, Colgalt1flox+ mice were generated using gene editing techniques, followed by crossing with Lyz2-Cre+ mice, which exhibit tissue-specific expression in the myeloid lineage (including monocytes and mature macrophages). Through this strategy, mice with the genotype Colgalt1-/- Lyz2-Cre+ were successfully obtained, achieving conditional knockout of the Colgalt1 gene in macrophages. Colgalt1flox/flox Lyz2-Cre- mice were used as control. PCR and agarose gel electrophoresis were employed to identify the Flox and Cre genotypes of the knockout mice. RT-qPCR and Western Blot techniques were utilized to detect the expression levels of Colgalt1 in BMDMs from knockout mice at both the mRNA and protein levels, respectively. Western Blot results revealed a significant downregulation of Colgalt1 expression in BMDMs from knockout mice compared to controls (P<0.01). RT-qPCR results demonstrated a significant reduction in Colgalt1 mRNA levels in BMDMs from knockout mice compared to controls (P<0.001), while no significant differences in Colgalt1 mRNA expression were observed in liver, lung, or spleen tissues between the two groups. Additionally, immunohistochemistry was employed to detect Colgalt1 expression in liver-specific macrophages, revealing an absence of Colgalt1-positive staining in liver macrophages from knockout mice. HE staining was used to observe cellular morphology in liver tissues from both groups of mice, showing no significant differences in cellular morphology or obvious pathological changes in tissues and organs. Moreover, the overall survival of the mice was not affected. Finally, RT-qPCR was used to assess the expression of macrophage-related inflammatory factors in BMDMs from both groups of mice. The results indicated that compared to controls, knockout mice exhibited downregulated expression of TNF-α (P<0.05) and significantly upregulated expression of IL-10 (P<0.01), Arginase1 (P<0.001), and CD206 (P<0.001) in BMDMs, suggesting an anti-inflammatory trend and M2 polarization of macrophages following Colgalt1 knockout. In summary, this study successfully established a macrophage-specific Colgalt1 gene knockout mouse model, providing a more reliable experimental animal model for in-depth exploration of the specific roles of Colgalt1 in macrophage functional regulation and the pathogenesis of tumor-related diseases. This model holds promise for identifying novel therapeutic targets and strategies for tumors and other diseases.
The case teaching mode, as an important practical way of teaching reform in graduate education, plays a positive role in stimulating learning interest and improving comprehensive ability. As a core course in biology, advanced immunology is characterised by the depth of its theoretical system and the boundaries of its research scope. In this paper, we first analyzed the significance and current situation of case library construction at home and abroad, and pointed out the key issues that need to be further optimised in the existing case teaching mode. Based on the construction strategy of "Advanced Immunology", three typical teaching cases, namely tumour treatment strategy, gene editing technology to overcome organ transplant rejection, and synthetic immunology, are selected for empirical research, focusing on graduate students’ innovative ability to raise questions and solve problems. The effectiveness of teaching practice was summarized from the improvement of teachers’ ability, the award-winning of students’ disciplinary competitions, and the co-construction between the university and enterprises, which has a significant effect and guarantees the benign optimization of the teaching reform of immunology, and also has the popularization value and exemplary effect on the high-quality development of immunology-related courses.
Monthly journal, established in 1985 Sponsored by：
Chinese Society of Biochemistry and Molecular Biology
Peking University Undertaken by:
Peking University Health Science Center Edited by:
Editorial Office of Chinese Journal of Biochemistry and Molecular Biology Editor-in-Chief:
ZHOU Chun-Yan
ISSN 2097-4329 (Online)
ISSN 1007-7626 (Print)
CN 11-3870/Q
