Fusions of Dendritic Cells and C6 Cells Transfected with TGF-β1 Antisense in Treatment of Intracranial Gliomas

Objective： To investigate the immunotherapy efficacy of fusion cells （dendritic-C6anti-TGF-β1 cells） in the treatment of intraeranial gliomas. Methods： Dendritic cells were isolated from rat bone-marrow precursors stimulated in vitro with granuloeyte-macrophage colony-stimulating factor （GM-CSF） and Interleukin-4 （IL-4）. C6anti-TGF-β1 cells originally from C6 cell line of a rat glioblastoma were transfected with plasmid of TGF-β1 anti-sense gene. Fusions of dendritic cells and C6anti-TGF-β1 cells were prepared by polyethylene glycol （PEG）. The DC/C6anti-TGF-β1 fusion cells were observed and confirmed by fight microscopy and scanning electron microscopy. Experimental rats were divided into three groups at random： C6 cells （Ⅰ）, dendritic-C6anti-TGF-β1 fusion cells and C6 cells （Ⅱ） and IMDM medium only （Ⅲ）. The cells were injected into right parietal lobe region of the rat with stereotaxic technique. Histology, tumor necrosis and survival time were evaluated. Results： Compared with the rats that received C6 cells （survival median time was less than 20 days, tumor region was seen in all fields of observed）, the rats injected with dendritic-C6anti-TGF-β1 fusion cells and C6 cells got a more prolonged life span （more than 59 days）, as well as less tumor region （5.01%-6.2%）. There was no tumor necrosis, but some glias were seen in surroundings. All rats were survived and no necrosis was observed in negative control group. Statistical analysis showed that group Ⅱ had significant difference compared with group Ⅰ. Conclusions： Dendritic-C6anti-TGF-β1 fusion cells could prolong the life span of rats, providing a strategy to achieve an antitumor response against tumors in the central nervous system.

Effect of a cancer vaccine prepared by fusions of hepatocarcinoma cells with dendritic cells

AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine spleen, which suggests that the fusion cells have already obtained the function of antigen presenting of parental DC and could present H(22)specific antigen which has not been identified yet, and H(22)-DC could induce antitumor immune response; although simply mixed H(22) cells with DC could stimulate the specific CTL activity which could inhibit the growth of tumor in some degree, it could not prevent the generation of tumor. It shows that the DC vaccine is likely to become a helpful approach in immunotherapy of hepatocarcinoma.

Effect of cell fusion on metastatic ability of mouse hepatocarcinoma cell lines

AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations, cell fusion and limit dilution, 8 Ag resistant cells were selected, and HGPRT - Hca P cells and eight cloned hybridoma cells were obtained. To observe their metastatic ability, they were inoculated into mice foodtaps and the drainage lymph nodes were examined under microscope. RESULTS The end concentration of 8 Ag which was used to select HGPRT deficient Hca P cells was 30mg/L . All the cells selected died in HAT culture medium in one week. Fused cells appeared approximately 9 days later. They were round, transparent and a little larger than their parental cells. Eight clones of hybridoma cells were obtained and named as PSH1 PSH8. The metastatic rate of HGPRT - Hca P cells and PSH7 cells was 28 6% and 71 4% respectively, the difference being significant ( P <0 05). The metastatic rate of other clones was no more than 20% and there was no significant difference from HGPRT - Hca P cells ( P >0 05). CONCLUSION In normal mice splenic lymphocytes, there are some factors that could inhibit tumor metastasis, however, there are some other factors accelerating tumor cells to metastasize. The establishment of PSH7 provides an experimental model which could be used to study the factors involved in metastasis.

Roles of cell fusion, hybridization and polyploid cell formation in cancer metastasis

Cell-cell fusion is a normal biological process playing essential roles in organ formation and tissue differentiation,repair and regeneration.Through cell fusion somatic cells undergo rapid nuclear reprogramming and epigenetic modifications to form hybrid cells with new genetic and phenotypic properties at a rate exceeding that achievable by random mutations.Factors that stimulate cell fusion are inflammation and hypoxia.Fusion of cancer cells with non-neoplastic cells facilitates several malignancy-related cell phenotypes,e.g.,reprogramming of somatic cell into induced pluripotent stem cells and epithelial to mesenchymal transition.There is now considerable in vitro,in vivo and clinical evidence that fusion of cancer cells with motile leucocytes such as macrophages plays a major role in cancer metastasis.Of the many changes in cancer cells after hybridizing with leucocytes,it is notable that hybrids acquire resistance to chemo-and radiation therapy.One phenomenon that has been largely overlooked yet plays a role in these processes is polyploidization.Regardless of the mechanism of polyploid cell formation,it happens in response to genotoxic stresses and enhances a cancer cell’s ability to survive.Here we summarize the recent progress in research of cell fusion and with a focus on an important role for polyploid cells in cancer metastasis.In addition,we discuss the clinical evidence and the importance of cell fusion and polyploidization in solid tumors.

Fusion of bone marrow-derived cells with cancer cells: metastasis as a secondary disease in cancer

This perspective article highlights the leukocyte-cancer cell hybrid theory as a mechanism for cancer metastasis. Beginning from the first proposal of the theory more than a century ago and continuing today with the first proof for this theory in a human cancer, the hybrid theory offers a unifying explanation for metastasis. In this scenario, leukocyte fusion with a cancer cell is a secondary disease superimposed upon the early tumor, giving birth to a new, malignant cell with a leukocyte-cancer cell hybrid epigenome.

New model for cardiomyocyte sheet transplantation using a virus-cell fusion technique

AIM: To facilitate close contacts between transplanted cardiomyocytes and host skeletal muscle using cell fusion mediated by hemagglutinating virus of Japan envelope(HVJ-E) and tissue maceration. METHODS: Cardiomyocytes(1.5 × 106) from fetal rats were first cultured. After proliferation, some cells were used for fusion with adult muscle fibers using HVJ-E. Other cells were used to create cardiomyocyte sheets(area: about 3.5 cm2 including 2.1 × 106 cells), which were then treated with Nile blue, separated, and transplanted between the latissimus dorsi and intercostal muscles of adult rats with four combinations of HVJ-E and/or Na OH maceration: G1: HVJ-E(+), Na OH(+), Cardiomyocytes(+); G2: HVJ-E(-), NaO H(+), Cardiomyocytes(+); G3: HVJ-E(+),Na OH(-), Cardiomyocytes(+); G4: HVJ-E(-), Na OH(-), Cardiomyocytes(-). At 1 and 2 wk after transplantation, the four groups were compared by detection of beating domains, motion images using moving target analysis software, action potentials, gene expression of MLC-2v and Mesp1 by reverse transcription-polymerase chain reaction, hematoxylin-eosin staining, and immunostaining for cardiac troponin and skeletal myosin.RESULTS: In vitro cardiomyocytes were fused with skeletal muscle fibers using HVJ-E. Cardiomyocyte sheets remained in the primary transplanted sites for 2 wk. Although beating domains were detected in G1, G2, and G3 rats, G1 rats prevailed in the number, size, motion image amplitudes, and action potential compared with G2 and G3 rats. Close contacts were only found in G1 rats. At 1 wk after transplantation, the cardiomyocyte sheets showed adhesion at various points to the myoblast layer in the latissimus dorsi muscle. At 2 wk after transplantation, close contacts were seen over a broad area. Part of the skeletal muscle sarcoplasma seemed to project into the myocardiocyte plasma and some nuclei appeared to share both sarcoplasmas.CONCLUSION: The present results show that close contacts were acquired and facilitated the beating function, thereby providing a new cellular transplantation method using HVJ-E and NaO H maceration.

Detection of fusion gene in cell-free DNA of a gastric synovial sarcoma

Synovial sarcoma(SS) is genetically characterized by chromosomal translocation, which generates SYT-SSX fusion transcripts. Although SS can occur in any body part, primary gastric SS is substantially rare. Here we describe a detection of the fusion gene sequence of gastric SS in plasma cell-free DNA(cf DNA). A gastric submucosal tumor was detected in the stomach of a 27-year-old woman and diagnosed as SS. Candidate intronic primers were designed to detect the intronic fusion breakpoint and this fusion sequence was confirmed in intron 10 of SYT and intron 5 of SSX2 by genomic polymerase chain reaction(PCR) and direct sequencing. A locked nucleic acid(LNA) probe specificto the fusion sequence was designed for detecting the fusion sequence in plasma and the fusion sequence was detected in preoperative plasma cfD NA, while not detected in postoperative plasma cfD NA. This technique will be useful for monitoring translocation-derived diseases such as SS.

TRANSFECTION AND CELL FUSION BY FEMTOSECOND LASERS

Biophotonics is an exciting and fast-expanding frontier which involves the fusion of advanced photonics and biology.It has not only created many novel methodologies for biomedical research,but also achieved many significant results as an independentfield.Thanks to femtosecond(fs)laser technologies,important progresses have been made regarding the manipulation,imaging,and engineering of biological samples ranging from single molecules to tissues in the last 20 years.The ultrashort pulses at near-infrared band provide many advantages:high nonlinear efficiency,low absorption by biological samples,high spatial and temporal resolution and confinement,and low phototoxicity.They are noninvasive and easy to control.Although the mechanism of how fs laser pulses interact with cells remains unclear,experimental results have shown that they could open up the cell membrane and hence made optical transfection and optical cell fusion possible.In this review,some of the seminal works on transfection and cell fusion by fs lasers are presented.The ideas behind and the experimental details will be described together with a highlight on their significances.Specifically,the thermal effect is analyzed based on multiphoton excitation and plasma formation in an aqueous environment to explain the nontoxic characteristic of fs laser irradiation.Last,some applications of fs laser induced transfection and cell
cell fusion with potential major impact in biomedical sciences are proposed.

Reprogramming somatic cells by fusion with embryonic stem cells does not cause silencing of the Dlk1-Dio3 region in mice

AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined by real-time reverse transcription-polymerase chain reaction.Pyrosequencing and bisulfate sequencing were used to determine the DNA methylation level of the Dlk1-Dio3 locus imprinting control region. RESULTS:The selected hybrid clones had a near-tetraploid karyotype and were highly pluripotent judging from their capacity to generate chimeric embryos and adult chimeras.Our data clearly demonstrate that Gtl2,Rian,and Mirg,which are imprinted genes within the Dlk1-Dio3 locus,are active in all examined ES cell/fibroblast hybrid clones.In spite of interclonal variability,the expression of the imprinted genes is comparable to that of ES cells and fibroblasts.Quantitative analysis of the DNA methylation status of the intergenic differentially methylated region(IG DMR)within the Dlk1-Dio3 locus by pyrosequencing and bisulfite sequencing clearly showed that the DNA methylation status of the imprinted region in the tested hybrid clones was comparable to that of both ES cells and fibroblasts.CONCLUSION:Reprogramming process in a hybrid cell system is achieved without marked alteration of the imprinted Dlk1-Dio3 locus.

Sum Frequency Spectroscopy Studies on Cell Membrane Fusion Induced by Divalent Cations

Cell membrane fusion is a fundamental biological process involved in a number of cellular living functions. Regarding this, divalent cations can induce fusion of the lipid bilayers through binding and bridging of divalent cations to the charged lipids, thus leading to the cell membrane fusion. However, the elaborate mechanism of cell membrane fusion induced by divalent cations is still needed to be elucidated.Here, surface/interface sensitive sum frequency generation vibrational spectroscopy(SFG-VS) and dynamic light scattering(DLS) were applied in this research to study the responses of phospholipid monolayer to the exposure of divalent metal ions i.e.Ca^(2+)and Mg^(2+). According to the particle size distribution results measured by DLS experiments, it was found that Ca^(2+)could induce inter-vesicular fusion while Mg^(2+)could not. An octadecyltrichlorosilane self-assembled monolayer(OTS SAM)-lipid monolayer system was designed to model the cell membrane for the SFG-VS experiment. Ca^(2+)could interact with the lipid POO_(2)^(-)head groups more strongly, resulting in cell membrane fusion more easily, in comparison with Mg^(2+). No specific interaction between the two metal cations and the C=O groups was observed. However, the C=O orientations changed more after Ca^(2+)-PO2-binding than Mg^(2+)mediation on lipid monolayer. Meanwhile, Ca^(2+)could induce dehydration of the lipids(which should be related to the strong Ca^(2+)-PO_(2)^(-)interaction), leading to the reduced hindrance for cell membrane fusion.

Cloned s-Lap Gene Coding Area, Expression and Localization of s-Lap/GFP Fusion Protein in Mammal Cells

s-Lap is a new gene sequence from pig retinal pigment epithelial(RPE) cells, which was found and cloned in the early period of apoptosis of RPE cells damaged with visible light. We cloned the coding area sequence of the novel gene of s-Lap and constructed its recombinant eukaryotic plasmid pcDNA3.1-GFP/s-lap with the recombinant DNA technique. The expression and localization of s-lap/GFP fusion protein in CHO and B_~16 cell lines were studied with the instantaneously transfected pcDNA3.1-GFP/s-lap recombinant plasmid. ~s-Lap/GFP fusion protein can be expressed in CHO and B_~16 cells with a high rate expression in the nuclei.

Cell fusion in the liver, revisited

There is wide agreement that cell fusion is a physiological process in cells in mammalian bone, muscle and placenta. In other organs, such as the cerebellum, cell fusion is controversial. The liver contains a considerable number of polyploid cells: They are commonly believed to originate by genome endoreplication, although the contribution of cell fusion to polyploidization has not been excluded. Here, we address the topic of cell fusion in the liver from a historical point of view. We discuss experimental evidence clearly supporting the hypothesis that cell fusion occurs in the liver, specifically when bone marrow cells were injected into mice and shown to rescue genetic hepatic degenerative defects. Those experiments-carried out in the latter half of the last century-were initially interpreted to show "transdifferentiation", but are now believed to demonstrate fusion between donor macrophages and host hepatocytes, raising the possibility that physiologically polyploid cells, such as hepatocytes, could originate, at least partially, through homotypic cell fusion. In support of the homotypic cell fusion hypothesis, we present new data generated using a chimera-based model, a much simpler model than those previously used. Cell fusion as a road to polyploidization in the liver has not been extensively investigated, and its contribution to a variety of conditions, such as viral infections, carcinogenesis and aging, remains unclear.

EFFECTS OF CALM /AF10 ANTISENSES ON PRIMARY LEUKEMIC CELLS WITH CALM /AF10 FUSION TRANSCRIPTS IN VITRO

Objectives: To define the involvement of CALM and AF10 fusion transcripts in primary leukaemias with t(10; 11). Methods: The AF10 and CALM fusion in five t(10; 11) leukemia samples were checked by reverse transcriptase-polymerase chain reaction (RT-PCR), and effects of CALM/AF10 antisense phosphorothioate oligodeoxynucleotides (AS PS-ODNs) on chemotherapy sensitivity and apoptosis of leukemia cells in vitro were observed. Results: Five different-sized AF10-CALM products and four different-sized CALM/AF10 products were detected by RT-PCR. The chemotherapy sensitivity of leukemic cells with t(10; 11) to drugs in vitro was lower than that of leukemic cells without t(10; 11). AS PS-ODNs increased the chemotherapy sensitivity and apoptotic rate. There were 4 cases positive at 5 μmol/L concentration, all cases positive at 10 μmol/L and 20 μmol/L concentration, P<0.01 vs only chemotherapeutic drugs (3 cases positive), and chemotherapeutic drugs + S-PS-ODNs (10 μmol/L) (3 cases positive). After cells were treated with 10 μmol/L AS-PS-ODNs + chemotherapeutic drugs for 48 h, 72 h, 96 h, the apoptotic indexes were 14.22±2.86, 29.39±3.57, and 41.26±4.52, respectively. These were significantly higher than those of only chemotherapeutic drugs-treated cells and chemotherapeutic drugs + S-PS-ODNs-treated cells at corresponding time (P<0.01). There was no difference between only drugs group and S-PS-ODNs group at corresponding time (P>0.05). Conclusion: The CALM and AF10 fusion transcripts are involved in the pathogenesis of haematological malignancies with t(10, 11), and is associated with a poor prognosis. AS-PS-ODNs might be useful in therapy of t(10, 11) leukemia. Key words AF10 - CALM - Fusion transcript - Primary leukemia cell - In vitro sensitivity - Antisense oligodeoxynucleotide CLC number R733.7 Biography: LIU Ge-xiu (1968–), male, associate professor, Institute of Hematology, Medical College, Jinan University, majors in hematology.

局部和全局特征融合的太阳能电池片表面缺陷检测

太阳能电池片表面缺陷具有类内差异大、类间差异小和背景特征复杂等特点,因此,要实现高精度的太阳能电池片表面缺陷自动检测是一项富有挑战性的任务。针对此问题,该文提出融合局部和全局特征的卷积视觉Transformer网络(CViT-Net),首先采用Ghost聚焦(G-C2F)模块提取电池片缺陷局部特征;然后引进坐标注意力强调缺陷特征并抑制背景特征;最后构建Ghost视觉(G-ViT)模块融合电池片缺陷局部特征和全局特征。同时,针对不同检测精度和模型参数量,分别提供了CViT-Net-S和CViT-Net-L两种网络结构。实验结果表明,与经典MobileVit、MobileNetV3和GhostNet轻量级网络相比,CViT-Net-S对电池片分类准确率分别提升了1.4%、2.3%和1.3%,对电池片检测mAP50分别提升了2.7%、0.3%和0.8%;与ResNet50、RegNet网络相比,CViT-Net-L分类准确率分别提升了0.72%和0.7%,检测mAP50分别提升了3.9%、1.3%;与先进YOLOv6、YOLOv7和YOLOv8检测网络相比,作为骨干网络的CViT-Net-S、CViT-Net-L结构在mAP和mAP50指标上仍保持良好检测效果。结果证明本文算法在太阳能电池片表面缺陷检测领域具有应用价值。

Promotion of Chondrogenesis of Marrow Stromal Stem Cells by TGF-β3 Fusion Protein In Vitro

The purpose of this study was to investigate the repair of the osteoarthritis（OA）-induced car- tilage injury by transfecting the new TGF-β3 fusion protein （LAP-MMP-mTGF-β3） with targeted ther- apy function into the bone marrow-derived mesenchymal stem cells （MSCs） in rats. The recombinant of plRES-EGFP-MMP was constructed by combination of DNA encoding MMP enzyme cutting site and eukaryotic expression vector plRES-EGFP. LAP and mTGF-β3 fragments were obtained from rat em- bryos by RT-PCR and inserted into the upstream and downstream of MMP from plRES-EGFP-MMP respectively, so as to construct the recombinant plasmid ofplRES-EGFP-LAP-MMP-mTGF-β3, plRES- EGFP-LAP-MMP-mTGF-β3 was transfected into rat MSCs. The genetically modified MSCs were cul- tured in medium with MMP-1 or not. The transfected MSCs were transplanted in the rat OA models. The OA animal models were surgically induced by anterior cruciate ligament transaction （ACLT）. The pathological changes were observed under a microscope by HE staining, Alcian blue, Safranin-fast Gre- en and graded by Mankin＇s scale, plRES-EGFP-LAP-MMP-mTGF-β3 was successfully constructed by means of enzyme cutting and sequencing, and the mTGF-β3 fusion protein （39 kD） was certified by Western blotting. Those genetically modified MSCs could differentiate into chondrocytes induced by MMP and secrete the relevant-matrix. The transfected MSCs could promote chondrogenesis and matrix production in rat OA models in vivo. It was concluded that a new fusion protein LAP-MMP-mTGF-β3 was constructed successfully by gene engineering, and could be used to repair the OA-induced cartilage injury.

Anti-tumor effects of p53N15-based fusion peptide in the transfected H1299 lung cancer cells

Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung cancer cell line,and evaluate the anti-tumor effects of the fusion peptide. Methods Adeno-associated virus (AAV) vectors were used for transfecting p53N15 fusion peptide into p53-null lung adenocarcinoma H1299 cells.

Detection of TMPRSS2：ERG fusion gene in circulating prostate cancer cells

Aim： To investigate the existence of TMPRSS2：ERG fusion gene in circulating tumor cells （CTC） from prostate cancer patients and its potential in monitoring tumor metastasis. Methods- We analyzed the frequency of TMPRSS2： ERG and TMPRSS2：ETV1 transcripts in 27 prostate cancer biopsies from prostatectomies, and TMPRSS2：ERG transcripts in CTC isolated from 15 patients with advanced androgen independent disease using reverse transcription polymerase chain reaction （RT-PCR）. Fluorescence in situ hybridization （FISH） was applied to analyze the genomic truncation of ERG, which is the result of TMPRSS2：ERG fusion in 10 of the 15 CTC samples. Results： TMPRSS2： ERG transcripts were found in 44% of our samples, but we did not detect expression of TMPRSS2：ETV1. Using FISH analysis we detected chromosomal rearrangements affecting the ERG gene in 6 of 10 CTC samples, including 1 case with associated TMPRSS2：ERG fusion at the primary site. However, TMPRSS2：ERG transcripts were not detected in any of the 15 CTC samples, including the 10 cases analyzed by FISH. Conclusion： Although further study is required to address the association between TMPRSS2：ERG fusion and prostate cancer metastasis, detection of genomic truncation of the ERG gene by FISH analysis could be useful for monitoring the appearance of CTC and the potential for prostate cancer metastasis.

去氢骆驼蓬碱诱发PC12细胞凋亡时对线粒体融合分裂的影响

目的探讨去氢骆驼蓬碱(HM)对PC12细胞线粒体功能损伤和线粒体融合分裂相关蛋白表达水平的影响。方法PC12细胞分为细胞对照组、HM组、线粒体分裂抑制剂Mdivi-1组、HM+Mdivi-1组、线粒体裂变激动剂WY14643组、HM+WY14643组,药物浓度均为1、10、25、50、100μmol·L^(-1),处理24 h,噻唑蓝(MTT)法检测细胞存活率,显微镜观察细胞形态;MitoTracker Red探针染色观察线粒体形态和纵横轴长度比值,JC-1染色检测线粒体膜电位,试剂盒检测ROS、ATP水平和乳酸脱氢酶(LDH)活性,免疫荧光染色法和Western blotting检测胱天蛋白酶3(caspase-3)、促凋亡蛋白(Bax)、细胞色素C(cyt-c)和线粒体融合蛋白(Mfn2)、线粒体分裂蛋白(Drp-1)的表达水平;电穿孔法转染Drp1的干扰序列,筛选转染效果好的siRNA序列,协同药物干预,通过荧光法、MTT法、免疫印迹法检测相关指标。结果MTT结果显示,与细胞对照组比较,HM组、Mdivi-1组、HM+Mdivi-1组、WY14643组和HM+WY14643组存活率显著下降(P<0.01),EC 50分别为(11.48±2.32)、(12.35±1.67)、(14.88±2.07)、(39.14±3.25)、(20.09±1.97)μmol·L^(-1),依此后续实验选择20μmol·L^(-1)浓度的HM、Mdivi-1和HM+Mdivi-1作为构建PC12细胞模型的工作浓度;显微镜和MitoTracker Red探针染色观察发现,药物组细胞密度呈不同程度减少,树枝状突起减少变圆;线粒体形态趋向圆形,纵横轴长度比值分别为细胞对照组(3.33±0.72)、HM组(2.19±0.58)、Mdivi-1组(2.45±0.44)、HM+Mdivi-1组(1.43±0.62)。JC-1染色检测结果显示,与细胞对照组相比,HM组线粒体模电位显著下降(P<0.01);ROS显著升高(P<0.01)、ATP水平下降(P<0.01),LDH酶活性上升(P<0.01);免疫荧光染色法和Western blotting结果显示,与细胞对照组比较,HM组促凋亡蛋白Bax、细胞色素C、胱天蛋白酶3表达水平均显著上升(均P<0.01);与细胞对照组比较,HM组细胞线粒体分裂相关蛋白Drp1表达水平显著上升(P<0.01),而线粒体融合相关蛋白Mfn2的表达水平显著下降(P<0.01);特异性干扰Drp1并协同HM干预后,各干扰组较各单独药物干预组PC12细胞存活率下降,Drp1和Mfn2表达下调,均差异有统计学意义(P<0.05或P<0.01)。结论HM可通过ROS累积降低PC12细胞膜电位及ATP,进而激活caspase-3凋亡途径促使细胞凋亡,线粒体融合分裂可能参与HM造成PC12细胞的损伤,启动细胞线粒体途径凋亡。

Xp11.2易位/TFE3基因融合相关性肾细胞癌的超声表现

目的探讨Xp11.2易位/TFE3基因融合相关性肾细胞癌(Xp11.2/TFE3-tRCC)的超声表现。资料与方法回顾性分析四川大学华西医院2009年4月—2022年2月手术经病理证实Xp11.2/TFE3-tRCC的10例患者,收集其超声图像及临床资料。观察肿块的边界、形态、内部回声、血流信号情况及超声造影表现等。结果共纳入10例肿块,其中4例行超声造影。Xp11.2/TFE3-tRCC的超声表现呈多样性及多变性,肿块好发于髓质(5例)。常规超声上6例表现为类似良性病灶的边界较清楚、形态较规则的实性结节,彩色多普勒显示5例为点状血流信号。超声造影上则更倾向于恶性肿块(3例),具体表现为不均匀强化,多伴有周边不均匀增强环。结论Xp11.2/TFE3-tRCC的常规超声表现多倾向良性,而超声造影则表现为恶性病灶,因此超声造影可作为诊断可疑Xp11.2/TFE3-tRCC的潜在方法。

细胞之间线粒体转移的主要途径、主要作用及主要调控机制

背景:线粒体功能障碍导致细胞衰老凋亡,可加重组织损伤。细胞之间线粒体转移促进损伤细胞恢复线粒体功能,有助于治疗线粒体相关疾病。目的:综述细胞之间线粒体转移的作用及调控机制。方法:检索中国知网和PubMed数据库2014-2024年关于细胞之间线粒体转移的文献,以“线粒体转移,隧道纳米管,缝隙连接,微囊泡,细胞融合”为中文检索词,以“Mitochondrial transfer,Tunneling nanotubes,gap junctions,microvesicles,cell fusion”为英文检索词,最终共纳入74篇文献进行分析。结果与结论:①总结了细胞之间线粒体转移的4个主要途径:包括隧道纳米管、缝隙连接、细胞融合和微囊泡。②梳理了细胞之间线粒体转移的主要作用,包括物质交换、信息传递、改善宿主细胞线粒体功能、抑制氧化应激、提高细胞增殖活力及抗炎抗衰老等。③总结了细胞之间线粒体转移的主要调控机制,包括Miro 1促进隧道纳米管形成和线粒体转移、隧道纳米管转移线粒体依赖宿主细胞环状ADP核糖水解酶表达、氧化应激环境诱导隧道纳米管形成、缝隙连接具有Ca^(2+)依赖性、缝隙连接蛋白43影响缝隙连接形成、激活Ras1蛋白和肌动蛋白有助于细胞融合、肌动蛋白和Rab6参与调控线粒体出胞、激活肌动蛋白和NAD+-CD38-cADPR-Ca^(2+)信号通路促进线粒体入胞等。④在细胞信号传导蛋白、细胞动力学相关蛋白及氧化应激环境的影响下,细胞通过隧道纳米管、缝隙连接、微囊泡及细胞融合进行线粒体转移。⑤线粒体转移是细胞之间物质交换和信息交流的重要途径,与疾病的发生发展息息相关,可为治疗线粒体相关疾病提供新的思路,但对细胞间线粒体转移的作用及调控机制仍需进一步探究。