Aging is the result of the accumulation of various molecular and cellular damages over time, encompassing 12 characteristic hallmarks divided into three categories. These include primary hallmarks such as genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, and disabled macroautophagy; antagonistic hallmarks like deregulated nutrient sensing, mitochondrial dysfunction, and cellular senescence; and integrative hallmarks including stem cell exhaustion, altered intercellular communication, chronic inflammation and dysbiosis. Therefore, investigating cellular signaling factors within a single pathway is insufficient to comprehensively understand the complex mechanisms underlying aging. Casein kinase II (CK2), one of the earliest identified protein kinases, is capable of phosphorylating serine/threonine/tyrosine residues on hundreds of substrates. It exhibits highly constitutive expression and activity, and is extensively involved in the regulation of cellular processes such as proliferation, differentiation, apoptosis, stress response, metabolism, and immune function. CK2 plays a unique role in coordinating the cross-talk and integration of various signaling pathways, which is crucial for maintaining cell survival and homeostasis. Recent studies have revealed that CK2 exhibits perturbations in both expression levels and enzymatic activity during aging process, with notable heterogeneity observed across different animals, tissues and cellular models. Overall, the downregulation of CK2 expression not only promotes the development of primary hallmarks but also alleviates antagonistic hallmarks and ameliorates integrative hallmarks of aging, demonstrating dual effect and interconnected mechanisms. Notably, aberrant activation in CK2 expression and activity are associated with various aging-related diseases, including cancer, cardiovascular diseases, chronic metabolic disorders, neurodegenerative diseases and skeletal degenerative conditions. Therefore, maintaining CK2 homeostasis may represent an effective strategy for delaying aging. This review summarizes the latest advances in CK2 and aging research, providing not only deeper insights into the common mechanisms underlying aging and aging-related diseases, but also a theoretical foundation for identifying potential targets for the early prevention of aging-related diseases.

Circular RNA (circRNA) is a single-stranded RNA with a covalently closed loop structure, which has a more stable structure and lower immunogenicity than linear RNA. Many studies have shown that circRNA has characteristics such as conservation, stability, and tissue specificity, and can act as a microRNA (miRNA) sponge to interact with proteins and translation templates, and regulate biological functions such as gene expression and signal transduction. Based on the characteristics and various biological functions of circRNA, some endogenous circRNA plays an important regulatory role in the occurrence and development of tumors and has the potential to be used as biomarkers and therapeutic targets. In addition, mRNA drugs have limitations such as instability, easy degradation, low translation efficiency, and immunogenicity in practical applications. Engineered translatable exogenous circRNA can solve some of the limitations of linear mRNA application and become a new type of potential efficient drug. In this paper, we introduce the circRNA biogenesis mechanisms, specific biological functions, and the current status of diagnosis and treatment applications in tumors. This includes the diagnostic application of endogenous circRNA in tumors, the design and synthesis strategies of exogenous circRNA, and the current progress in the design and application of engineered circRNA vaccines using their stable and efficient protein expression functions in the treatment of tumors. Finally, we discuss the current clinical diagnostic application problems of circRNA, the challenges of exogenous circRNA therapeutic applications, and the prospects of the field.

Ferroptosis is a new form of programmed cell death with iron-dependent lipid peroxidation as its core. A variety of metabolites are involved in the regulation of ferroptosis, among which lipid metabolism plays an important role. The most classic lipid metabolism-mediated ferroptosis mechanism is that phospholipids containing polyunsaturated fatty acyl chain (PUFA-PLs) located on biological membranes undergo super-threshold peroxidation, which leads to the destruction of membrane structure and function. In addition, special lipids containing polyunsaturated fatty acid (PUFA), such asphospholipid withdiacyl-PUFA tails (PL-PUFA₂), polyunsaturated ether phospholipid (PUFA-ePL), cholesterol ester containing polyunsaturated fatty acyl chain (PUFA-CE) have also been found to be involved in the ferroptosis process by providing PUFA for peroxidation. Lipid droplets was also found to regulate the sensitivity of ferroptosis through storing and releasing PUFA. Intermediates and derivatives of cholesterol metabolism are mainly involved in the negative regulation of ferroptosis, whereas different classes of sphingolipids were reported to have inconsistent regulatory directions for ferroptosis. A large number of previous studies have confirmed that ferroptosis is closely related to the metastasis and drug resistance of gastrointestinal tumors, therefore, we further summarized the lipid metabolism mechanisms related to ferroptosis resistance in gastrointestinal tumor cells, such as weakening the anabolism and peroxidation processes of PUFA-PLs, enhancing the ferroptosis defense system and so on. At the same time, we elaborated on the relationship between cholesterol metabolism, lipid drop metabolism, sphingolipid metabolism, and ferroptosis resistance in gastrointestinal tumors. Targeting these specific lipids, metabolic enzymes, and pathways to regulate ferroptosis has important clinical potential value. It is expected to provide new ideas for finding new diagnostic and prognostic markers, therapeutic drugs, and reversing chemotherapy resistance for gastrointestinal tumors.

The emergence of CRISPR/Cas system has greatly promoted the progress in the field of gene editing, especially CRISPR/Cas9 system, which has become a core tool in biomedical research. Long noncoding RNAs (lncRNAs) play a key role in gene regulation, cell differentiation and the development of a variety of diseases. Especially in cancer research, lncRNAs have important application prospects as cancer biomarkers and therapeutic targets. However, lncRNAs are generally characterized by low abundance and poor conservation, which limits the study of their functions by traditional means. CRISPR/Cas9 technology provides an efficient, flexible and accurate tool for lncRNA research, which significantly accelerates the progress in this field. This paper first reviews the basic principles of CRISPR/Cas9 system and its wide applications in gene editing, including CRISPR knockout, knock-in, interference, activation and other functional systems. These technologies can not only screen key lncRNAs in specific biological processes, but also be used for gene function research to explore their roles in diseases. This article focuses on the analysis of CRISPR/Cas9 technology in the study of lncRNA functions, regulatory mechanisms, and its key applications in tumor research. In addition, the article also summarizes the methods of genome-wide screening by CRISPR/Cas9 to identify functional lncRNAs, and discusses the roles of these lncRNAs in cancer cell proliferation, migration, invasion and drug resistance. CRISPR/Cas9 knockout system can efficiently knock down lncRNA genes and reveal their specific functions in gene regulation. At the same time, CRISPR activation and interference technology provide a new idea for the research of noncoding genes, and further explore its clinical application in cancer and other diseases by regulating the expression level of lncRNAs. The article also discusses the potential of CRISPR technology in future lncRNA research, especially the progress in solving technical problems such as genome complexity, targeting efficiency and off-target effects. As mentioned in the review, CRISPR/Cas9 technology not only provides a powerful tool for studying lncRNAs, but also provides new ideas and opportunities for developing new means of cancer diagnosis and treatment in the future.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths, and although considerable progress has been made in the clinical diagnosis and treatment of HCC, the prognosis for patients remains poor, with a 5-year survival rate of only about 18%. The development of HCC is driven by the occurrence of mutations in driver genes that can directly promote cell proliferation, survival and metastasis. With the development of molecular biology and genomics technologies, researchers have elucidated that driver mutations that give HCC cells a selective growth advantage, the ability of the cells to resist apoptosis, maintain proliferative signals, initiate invasion and metastasis, induce angiogenesis, enable metabolic remodeling and immune escape. Exploring the key drivers of HCC development to further elucidate the pathogenesis of HCC may provide new directions for the diagnosis and treatment of HCC as well as improving the prognosis. In this paper, we summarize the driver gene mutations in HCC from various biological pathways such as telomere maintenance, cell cycle, the Wnt signaling pathway, oxidative stress, and epigenetic modifications. We also summarize the application prospects of driver gene mutations in the diagnosis and treatment of HCC. We aim to provide a reference for the diagnosis, treatment and research of HCC.

Liquid-liquid phase separation (LLPS) is the process where intracellular biomolecules rapidly form reversible high concentrations of liquid-phase condensates, resulting in the compartmentalization and the formation of intracellular membraneless organelles. LLPS is involved in various biological processes and pathologic processes, such as neurodegenerative diseases and cancers. Long noncoding RNAs (lncRNAs) have been revealed to be closely related to phase separation. It has become a research hotspot in life science recently, because it provides new insight into the mechanism of lncRNAs. In this review, we focuses on the effect of lncRNA SLERT on the phase separation of nucleolar fibrillar center/dense fibrillar component (FC/DFC) by interacting with DDX21 protein as a molecular chaperone; LINC00657 (NORAD) forms NP bodies with PUM proteins, which drives PUM protein liquid droplets and inhibits its activity, and promotes genomic stability; DilncRNA regulates DNA damage response small RNAs (DDRNAs) and LLPS of p53 binding protein 1 (53BP1) in response to DNA damage, and lncRNA LINP1 phase separation droplets bind to Ku protein to promote DNA damage repair; LncRNA SNHG9, MELTF-AS1 and MALR drive LATS1, YBX1 and ILF3 protein LLPS respectively to promote cancer, while GIRGL and lncFASA act as tumor suppressor genes in cancer development through regulating the phase separation of CAPRIN1 and PRDX1 respectively; LncRNA XIST drives X chromosome inactivation by LLPS. In a word, we summarize the latest research progress about the functional roles of lncRNAs in FC/DFC nucleolus, genomic stability and DNA damage and repair, cancer and X-chromosome inactivation through regulating LLPS. This paper shows that lncRNAs can participate in multiple pathophysiological processes by regulating LLPS, which is expected to provide a new direction for the treatment of LLPS-mediated diseases.

A mounting body of research suggests that circRNAs significantly contribute to the development of myocardial fibrosis. The microarray results of human circular RNA expression profile indicated that circHERC4_041 expression increased in the myocardium of patients with heart failure, RT-qPCR analysis confirmed that the myocardial expression level of circHERC4_041 in individuals with heart failure were considerably elevated compared to that in healthy organ donors. Fluorescence in situ hybridization (FISH) confirmed that circHERC4_041 was abundant in the cytoplasm of human cardiomyocyte AC16. Overexpression of circHERC4_041 in mouse myocardial fibroblasts (mCFs) mediated by adenovirus inhibited the expression of fibrosis-related proteins in mCFs. Experiments involving cell proliferation, wound healing, andTranswell assays demonstrated that overexpression of circHERC4_041 suppressed the growth and mobility of mCFs(P<0.001). Sequence analysis results suggested that circHERC4_041 contains potential ribosome entry sequence (IRES) and open reading frame (ORF). Western blot confirmed that circHERC4_041 could translate the 516 amino acid HERC4-516aa protein, which was mainly located in the cytoplasm of the cell. Cell functional experiments confirmed that circHERC4_041 inhibited the fibrotic phenotype of mCFs by specifically translating HERC4-516aa (P<0.05). The specific interaction between HERC4-516aa and transglutaminase 2 (TGM2) was confirmed by IP-MS screening and Co-IP identification. Further results found that the degradation of TGM2 was promoted through proteasome pathway. The overexpression of TGM2 in mCFs facilitated by adenoviral vectors could counteract the suppressive effects of HERC4-516aa on the fibrotic phenotype of mCFs. Therefore, this study confirmed that the HERC4-516aa protein translated by circHERC4_041 can specifically bind to TGM2 to inhibit the fibrotic phenotype of myocardial fibroblasts.

Protein-protein interactions play an extremely important role in the biochemical functions of cells, and in-depth analysis of protein interactions is the key to understanding cellular life activities. In this study, we systematically mined the interacting proteins of Golgi protein 73 (GP73) using classical immunoprecipitation combined with mass spectrometry, and sought to further analyze the molecular function of GP73. Hepatocellular carcinoma cell line HepG2 was selected, and a stable cell line overexpressing GP73-3Flag was constructed using lentiviral infection technology. A total of 78 high-confidence GP73 interacting proteins were identified by immunoprecipitation coupled with mass spectrometry. Bioinformatics analyses suggested that GP73 interacted with nearly 40 cytosolic proteins and participated in the biological processes of RNA transport, splicing, and translation. Further immunofluorescence and cytosolic protein isolation experiments confirmed the cytosolic localization of GP73 in a variety of tumor cells. Based on the 78 interacting proteins, we further screened protein interaction networks related to mRNA splicing and verified the existence of interactions between GP73 and seven proteins, including HNRNPH3, SMN1, RBM14, and NCBP1, by co-immunoprecipitation experiments. In addition, minigene splicing assay results indicated that GP73 inhibited the splicing efficiency of pre-mRNA by cells. This study contributes to the expansion of knowledge regarding the function of GP73 and aids in elucidating its critical role in cell biology and its potential association with diseases.

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase It mediates trimethylation of lysine 27 on histone H3, thereby facilitating the epigenetic silencing of downstream genes. In conjunction with SUZ12, EED, and other components, it constitutes the polycomb repressive complex 2 (PRC2) complex. While EZH2 is intricately involved in cellular proliferation and cardiac development, the changes in its expression during cardiac terminal differentiation remain elusive. In this study, we employed differential gene expression analysis of embryonic and adult myocardial cells using the GEO database, and found that EZH2 is highly expressed in embryonic myocardium, but is present at very low levels in adult myocardium (P<0.0001). Conversely, the expression changes of PRC2 members SUZ12 and EED are not as pronounced. Online analysis through the Tabula Muris database indicates that under physiological conditions, various cell subpopulations in the adult mouse heart exhibit negligible expression of EZH2. Immunohistochemical staining of mouse cardiac tissues shows that EZH2 is highly expressed in embryonic and neonatal myocardium but declines progressively from the first day after birth (P<0.0001), becoming almost undetectable by the third day. Western blotting further confirms the rapid disappearance of EZH2 expression post-birth (P<0.05), with EZH1 compensating for the downregulation of EZH2 to maintain H3K27me3 modification levels. Additionally, using the P19 teratocarcinoma stem cell model for cardiomyocyte differentiation, it is observed that EZH2 is significantly upregulated during the transition from cardiac progenitor cells to spontaneously beating cardiomyocytes, correlating with the expression of the cardiomyocyte transcription factor Gata4 (P<0.01). Targeted degradation of EZH2 using the small molecule drug MS1943 significantly inhibits the proliferation of induced cardiomyocytes, as evidenced by 5-ethynyl-2’-deoxyuridine (EdU) incorporation assays (P<0.01), and RT-qPCR reveals a marked increase in the expression of the proliferation inhibitor CDKN1A (P<0.01). In summary, the high expression of EZH2 in embryonic myocardial cells is associated with enhanced cell proliferation. The rapid loss of EZH2 expression postnatally correlates with the loss of proliferative capacity in cardiomyocytes, marking it as a key indicator of cardiac terminal differentiation.

AKT, also known as Protein Kinase B (PKB), plays a critical role in cell proliferation and metabolism. There are three isoforms of AKT: AKT1, AKT2, and AKT3. The effects of these isoforms on the pluripotency and differentiation of mouse embryonic stem cells (mESCs) remain unclear. This study aims to explore the impact of three AKT isoform-specific knockouts on the self-renewal and differentiation of mouse embryonic stem cells. Using CRISPR/Cas9 gene-editing technology, AKT isoform-specific knockout cell lines were established. The phenotypic and molecular changes were analyzed through Western blotting, flow cytometry, qRT-PCR, CCK-8 assays, Alkaline Phosphatase (AP) staining, and RNA-seq. The construction of AKT isoform-specific knockout cell lines was successful. The loss of AKT1 and AKT2 inhibited the proliferation of mESCs. The knockout of any single AKT isoform did not affect the expression of pluripotency genes at both mRNA or protein levels. However, during embryoid body formation, the deletion of any of the three AKT isoforms affected the mRNA expression levels of genes in all three germ layers. Transcriptome analysis showed that compared to wild-type mESCs, 995, 547, and 429 differentially expressed genes (|log2FC|≧1, P<0.05) were identified in AKT1, AKT2, and AKT3 isoform-specific knockout cells, respectively. There was some overlap in the differentially expressed genes regulated by these three isoforms. In conclusion, the independent knockout of AKT isoforms does not affect the maintenance of pluripotency in mouse embryonic stem cells, but they are crucial for differentiation. The three AKT isoforms can collectively regulate gene expression while retaining their own regulatory specificity. This study provides a foundation for understanding the unique and overlapping roles of AKT isoforms in stem cell biology, highlighting their importance in maintaining stem cell function and differentiation.

Metabolic reprogramming is a crucial feature of cancer. Among various metabolic processes, oxidative phosphorylation (OXPHOS) metabolism serves as the primary biochemical pathway for energy production and significantly influences tumorigenesis and tumor development. Therefore, this study aims to explore the impact of the metabolic characteristics of lung squamous cell carcinoma (LUSC) on its malignant properties. By analyzing the single-cell transcriptome sequencing data of LUSC, lung adenocarcinoma, and normal lung tissues from the gene expression profile database, it was found that the OXPHOS signaling pathway and molecules related to ATP synthesis were remarkably enriched in LUSC tissues. Based on the OXPHOS signal intensity score, LUSC cells were classified into OXPHOS^high and OXPHOS^low groups. Bioinformatics analysis revealed that 126 transcription factors were highly expressed in both LUSC tumor tissues and the OXPHOS^high group. Notably, the expression levels of cancer stem cell-related signals (such as SOX2, SOX9, POU2F1, CDX1, ARID3A, EZH2, and KLF5) were significantly enhanced in the OXPHOS^high cell subset (P<0.05). Treatment of LUSC cells with an OXPHOS antagonist significantly inhibited the sphere formation rate of H520 and SKMES-1 cells, which is a key characteristic of cancer stemness (P <0.05). Analysis of cell-cell communication data from the LUSC single-cell transcriptome indicated that the signal emission and reception in OXPHOS^high cells were stronger than those in OXPHOS^low cells. Moreover, fibroblasts showed significant interaction with OXPHOS^high-LUSC cells. Co-culture of LUSC cell lines H520 and SKMES-1 with human lung fibroblast-like cell lines significantly increased the sphere formation rate of tumor cells (P <0.05). Additionally, the levels of ATP, NADH-active enzymes, and reactive oxygen species (ROS) in co-cultured H520 and SKMES-1 cells were significantly elevated (P <0.05). The results of this study confirm that the OXPHOS pathway is a key signal involved in LUSC metabolism, which is closely associated with the characteristics of cancer stem cells and the regulatory signals of fibroblast interactions. This finding holds promises for providing novel strategies for tumor treatment.

The ocean plays a critical role in the global carbon cycle, and base on the "dual carbon" goals, ocean carbon sinks have received widespread attention. Shellfish aquaculture is one of the most important sources of carbon sinks in fisheries, which has an important impact on the offshore carbon cycle. As global temperature rises and ocean acidification intensifies, the capacity of the ocean to absorb CO₂ will change. However, the effects of high temperature on the physiology and transcriptome related to carbon metabolism in Mytilus coruscus are not clear enough. This study investigated the effects of high temperatures on the total carbon content, carbon metabolism, antioxidant-related enzyme activities, and the transcriptome of Mytilus coruscus. The results showed that high temperature significantly inhibited the activities of hexokinase and pyruvate kinase, increased carbonic anhydrase activity (P＜0.05), decreased the ATP content of digestive glands (P＜0.05), and affected glycolysis and the tricarboxylic acid cycle, leading to a significant decrease in the mussel’s ability to sequester carbon. High temperature resulted in significant (P<0.05) increases in the levels of reactive oxygen species and malondialdehyde, and enhanced the activities of superoxide dismutase and catalase. Observations by transmission electron microscopy showed that high temperatures damaged the subcellular structure of the digestive gland in Mytilus coruscus, resulting in the shrinkage of the nucleolus, swelling of the endoplasmic reticulum, and a significant reduction in the mitochondrial cristae. Comparative transcriptomic analysis showed that the upregulated DEGs were mainly enriched in protein processing in the endoplasmic reticulum, antigen processing and presentation, and MAPK signaling pathway. The downregulated DEGs were mainly enriched in necroptosis, DNA replication, and the NF-kappa B signaling pathway. In antioxidant-related DEGs, the upregulated DEGs include vitamin K epoxide reductase, peroxidases, heat shock protein 105 kD, heat shock protein 70 kD, and superoxide dismutase; The downregulated DEGs mainly included NADPH oxidase, glutathione reductase, cytochrome b-245, cytochrome P450, and quinone reductase. The upregulated genes enriched in the carbon metabolism pathway included chitinase, phosphatidylinositol 4, 5-bisphosphate 3-kinase, phosphoenolpyruvate carboxykinase, galactokinase, and inositol trisphosphate 3-kinase. The downregulated genes included aldose-1-epimerase, carbonic anhydrase, galactose mutarotase, acyl-CoA synthetase, alcohol dehydrogenase, and hexokinase. In conclusion, high temperature has an inhibitory effect on the activities of enzymes and the expression of genes related to carbon metabolism in Mytilus coruscus. The results of this study are intended to provide a scientific basis for the healthy development of mussel aquaculture and the assessment of carbon sinks.

Subunit 5B of constitutively photomorphogenic 9 signalosome (CSN5B) is an inhibitory factor for the biosynthesis of vitamin C in the L-galactose synthesis pathway in plants. To create mutants with richer vitamin C in tomato fruits, a dual-target vector of pKSE402-SlCSN5B was constructed and transformed into the breeding parent of 1912. Based on the molecular biological assay and DNA sequencing, 17 transgenic positive lines were determined, and 6 lines of them were genetically mutated at the target site of SlCSN5B, with an editing efficiency of 35.3%. Among the mutants, 2 lines were homozygous mutants, csn5b-6 with 180 bp deletion and csn5b-8 with 3 bp deletion. The biological traits of two types of deficiency homozygotes without exogenous T-DNA insertion derived from the T₁ generation were observed, and there were no significant differences in phenotypes of the plant and fruit. Through physiological testing of red-ripe fruits from T₁ generation lines of csn5b-6, the GMPase activity and the vitamin C content significantly increased by 43% and 37.8%, respectively, the content of hydrogen peroxide significantly decreased by 25.9%, and the content of soluble solids did not obviously change, compared with the wild type. There were no significant differences in plant traits and physiological characteristics between T₁ generation lines of csn5b-8 and the wild type. Based on gene expression analysis and protein structure prediction, the results showed that the gene of SlCSN5B normally transcribed, and the loss of large peptide segments of CSN5B encoded by SlCSN5B caused changes in its structure to affect functioning, which led to an increase of vitamin C content in the line of csn5b-6-11. The findings suggest that the vitamin C content of tomato fruit can be improved by CRISPR/Cas9-mediated SlCSN5B gene editing, which provides the valuable resources for high-quality breeding in tomato.

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives. Cultivating outstanding medical students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals. Our investigation revealed that within the imperfections of the cultivating model, some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities, which hinder the progression of scientific research activities. Consequently, we initiated a teaching practice and exploratory study on the “tutorial system” aimed at fostering medical students′ scientific research and innovation abilities. Based on the principle of "research informing teaching, teaching and research advancing together," this study implements a “tutorial system” coordinated by tutors, supplemented by graduate and undergraduate student mentors, to cultivate innovative thinking, stimulate interest in scientific research, and enhance practical and research skills among medical students. Through collaborative efforts within "scientific research innovation teams," various educational methods—including preliminary research, in-class and extracurricular activities, intra-group and inter-group interactions, and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students′ scientific research and innovation abilities. This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.