Functionally selective cannabinoid receptor signalling: Therapeutic implications and opportunities

The CB₁ and CB₂ cannabinoid receptors are G protein-coupled receptors (GPCRs) recognized by a variety of endogenous ligands and activating multiple signalling pathways. This multiplicity of ligands and intracellular transduction mechanisms supports a complex control of physiological functions by the endocannabinoid system, but requires a finely tuned regulation of the signalling events triggered on receptor activation. Here we review the diverse signalling pathways activated by the cannabinoid receptors and discuss the mechanisms allowing for specificity in the associated functional responses triggered by endogenous or exogenous ligands. At variance with the classical concept that all agonists at a given GPCR induce a similar repertoire of downstream events in all tissues, we also summarize the experimental evidence supporting the existence of functional selectivity and protean agonism at cannabinoid receptors. By placing emphasis on the ligand- or constitutive activity-dependent specifications of receptor-G protein coupling, these concepts explain how distinct cannabinoid ligands may activate specific downstream mediators. Finally, although both the diversity and specificity in cannabinoid signalling are now established in vitro, few data are available from in vivo studies. Therefore, we conclude this review by examining the experimental evidence supporting the physiological relevance of this complexity in the cannabinoid system. The ability to selectively manipulate physiological functions, through activation of defined signalling cascades, will in all likelihood help in the development of efficacious and safe cannabinoid-based therapeutics for a variety of indications.     

Global patent landscape of programmed cell death 1: implications of the rapid expansion

Introduction: Inhibitors of programmed cell death 1 (PD-1) and its ligands are producing a paradigm shift in cancer treatment. The promising clinical outcomes and a multi-billion dollar market have prompted active research and development and resulted in relentless patent protection. However, the global patent landscape in this field remains unclear.

Areas covered: The patent landscape encompassing global patenting activities and developing trends in the field is discussed based on a data set of 1287 patent families. Patenting activities have expanded rapidly in the past three years. Specific trends in relevant aspects are presented, including patent filing countries, patent ownership, co-patents, technical areas, and technological connections in terms of patent citation relationships.

Expert opinion: Together with patenting momentum in recent years, fragmented ownership and dense technological connections of PD-1-related inventions raise the possibility of a patent thicket. The explosion of patent applications and complex citation relationships could also lead to considerable patent conflicts and disputes on overlapping intellectual property rights, in addition to existing legal uncertainties. Patent applicants in this field are encouraged to be aware of these concerns when developing valid patent strategies.     

Cell-derived biomimetic nanocarriers for targeted cancer therapy: cell membranes and extracellular vesicles

Nanotechnology provides synthetic carriers for cancer drug delivery that protect cargos from degradation, control drug release and increase local accumulation at tumors. However, these non-natural vehicles display poor tumor targeting and potential toxicity and are eliminated by the immune system. Recently, biomimetic nanocarriers have been widely developed based on the concept of ‘mimicking nature.’ Among them, cell-derived biomimetic vehicles have become the focus of bionics research because of their multiple natural functions, such as low immunogenicity, long circulation time and targeting ability. Cell membrane-coated carriers and extracellular vesicles are two widely used cell-based biomimetic materials. Here, this review summarizes the latest progress in the application of these two biomimetic carriers in targeted cancer therapy. Their properties and performance are compared, and their future challenges and development prospects are discussed.     

Vorinostat in autophagic cell death: A critical insight into autophagy-mediated, -associated and -dependent cell death for cancer prevention

Histone deacetylases (HDACs) inhibit the acetylation of crucial autophagy genes, thereby deregulating autophagy and autophagic cell death (ACD) and facilitating cancer cell survival. Vorinostat, a broad-spectrum pan-HDAC inhibitor, inhibits the deacetylation of key autophagic markers and thus interferes with ACD. Vorinostat-regulated ACD can have an autophagy-mediated, -associated or -dependent mechanism depending on the involvement of apoptosis. Molecular insights revealed that hyperactivation of the PIK3C3/VPS34–BECN1 complex increases lysosomal disparity and enhances mitophagy. These changes are followed by reduced mitochondrial biogenesis and by secondary signals that enable superactivated, nonselective or bulk autophagy, leading to ACD. Although the evidence is limited, this review focuses on molecular insights into vorinostat-regulated ACD and describes critical concepts for clinical translation.     

程序性死亡配体-1在人非小细胞肺癌组织中的表达及临床意义

目的：探讨程序性死亡配体‐1（PD‐L1）在人非小细胞肺癌（NSCLC）组织中的表达及临床意义。方法采用Western blot和免疫组织化学染色法检测41例NSCLC患者的肺癌组织、癌旁组织、正常肺组织和15例肺部良性病变患者的正常肺组织中的 PD‐L1表达,分析NSCLC患者PD‐L1表达的影响因素。结果 NSCLC患者肺癌组织中 PD‐L1阳性表达率为80.49％（33／41）,肺良性病变患者正常肺组织中几乎无PD‐L1表达。NSCLC患者肺癌组织中 PD‐L1表达高于癌旁组织及正常肺组织（P＜0．05）。PD‐L1的表达与肿瘤患者分期、淋巴结转移和远处转移相关（P＜0．05）,而与肿瘤病理分型、患者年龄、性别、吸烟史及肿瘤大小等无关（ P＞0．05）。结论 PD‐L1在NSCLC组织中显著高表达,在NSCLC进展中发挥重要作用,可能成为NSCLC预后的判断指标及免疫治疗的新靶点。     

Mitochondria and reactive oxygen and nitrogen species in neurological disorders and stroke: Therapeutic implications

Mitochondria represent both the main source and target of reactive oxygen and nitrogen species (RONS). In view of the large energy expenditure made by neurons during neurotransmission, an intact mitochondrial function is of paramount importance for the correct function of the brain. Accordingly, the search of therapeutic strategies against situations in which there is an abnormal brain function, such as neurological disorders and stroke, should be focused towards mitochondria. Here, we have reviewed the normal and abnormal mitochondrial bioenergetics and dynamics, highlighting the relevance that, for these processes in the brain RONS exert. Evidence suggests that disruption of mitochondrial bioenergetics and dynamics may have a critical role in the pathogenesis of these brain diseases. Drug therapies directed toward providing safer mitochondria are currently under both pre- and clinical investigations.     

Chronic nickel-induced DNA damage and cell death: the protection role of ascorbic acid

High consumption of nickel-containing products leads to more exposure of humans to nickel and its by-products. Except the lethal effect of acute nickel poison, chronic nickel exposure is also harmful to humans, but the mechanism of chronic nickel-induced cytotoxicity remains unclear. Here, we found that long-term exposure of Ni(2+) led to significant DNA fragmentation, cell death, and reactive oxygen species (ROS) generation in human leukemia HL-60 cells. Induction of Ni(2+) on DNA fragmentation and cell death could be prevented by the antioxidants ascorbic acid (ASA) or N-acetyl-cysteine (NAC), or enhanced by H(2)O(2), indicating the involvement of ROS generation in the chronic nickel cytotoxicity in cells. Long-term exposure of mice to low Ni(2+) also led to a significant increase in both the ROS generation in the serum and the DNA fragmentation in the peripheral blood mononuclear cells (PBMC), while coadministration of ASA with Ni(2+) together significantly decreased both the DNA fragmentation and the ROS generation. Collectively, these results proved that ROS generation is at least one mechanism of the cytotoxicity of chronic nickel exposure, while ASA is probably useful for people to prevent the chronic nickel cytotoxicity, especially for those who work or live near a mining area or a factory related with nickel.     

程序性细胞死亡因子5在子宫内膜癌组织中的表达及意义

目的：探讨程序性细胞死亡因子5（PDCD5）的表达与子宫内膜癌发生的相关性。方法收集行手术治疗的60例子宫内膜癌组织、40例正常增生期子宫内膜组织及28例子宫内膜不典型增生组织,实时荧光定量PCR检测PDCD5 mRNA的表达,免疫组织化学法检测蛋白的表达。结果在正常增生期子宫内膜、子宫内膜不典型增生、子宫内膜癌组织中,PDCD5 mRNA的相对定量依次降低[（1．21±0．16）、（0．83±0.07）、（0．42±0．02）,F＝5．637,P＜0．05];PDCD5蛋白的阳性表达率依次降低（82．5％、64．3％、45．0％,χ2＝27．663,P＜0．05）;PDCD5的表达水平与子宫内膜癌患者的临床分期、组织学分级、肌层浸润以及淋巴结转移有关（χ2＝20．875、11．915、9．409、11．148,均P＜0．05）,而与年龄无关（χ2＝0．287,P＞0．05）。结论PDCD5的表达下调与子宫内膜癌的发生、发展有关,有可能成为一种潜在的早期预测子宫内膜癌的标志物。     

New 1,4-benzothiazepine derivative,K201, demonstrates cardioprotective effects against sudden cardiac cell death and intracellular calcium blocking action

In order to find drugs with suppressive effects against sudden cardiac cell death due to myofibrillar overcontraction, the cardioprotective effects of a new 1,4-benzothiazepine derivative, 4-[3-{1-(4-benzyl)piperidinyl}propionyl]-7-methoxy-2,3,4,5-tetrahydro-1,4-benzothiazepine, K201, in comparison with five other compounds, including a representative α-antagonist, β-antagonist, and Ca²⁺ channel antagonists, were investigated in an experimental myofibrillar overcontraction model of isolated rat heart. In addition, the effects of K201 on the contraction of isolated vascular smooth muscle of rat aorta and on the binding of cardiac annexin V with actin were compared with those of diltiazem and KT362. The degree of myofibrillar overcontraction was histologically scored on a four-grade scale (0, 1, 2, and 3) as myocardial injury score (MIS). Suppressive effects of myofibrillar overcontraction could not be observed with nicorandil and prazosin at 10^?5 M. Propranolol at 10^?5 M, verapamil at 10^?6 M, and diltiazem at 10^?6 M demonstrated a significant suppressive effect with MIS of 1.0 ± 0.4 (P < 0.01), 1.5 ± 0.3 (P < 0.01), and 1.5 ± 0.3 (P < 0.01), respectively. K201, even at 10^?7 M, displayed significant suppression with MIS of 1.8 ± 0.2 (P < 0.01). K201 inhibited contraction of isolated vascular muscle induced by K⁺ (40 mM) and NE (1 μM) at almost the same concentration. The lC₅₀ ratio (NE/K⁺) of K201 was 2.3. The inhibition by K201 of the response to K⁺ was less marked than that by diltiazem. Its inhibition of the response to NE was greater than that by diltiazem or KT362. K201 demonstrated an inhibitory effect on binding of cardiac annexin V with actin dependent on calcium concentration, but diltiazem and KT362 did not demonstrate any action to inhibit this reaction. These results indicate that K201 was a more effective cardioprotectant than propranolol, verapamil, and diltiazem in the experimental myofibrillar overcontraction model. K201 has intracellular Ca²⁺ blocking action in addition to weak α-1 adrenergic blocking activity and Ca²⁺ blocking activity. © 1994 Wiley-Liss, Inc.     

Inhibition of LOX-1 prevents inflammation and photoreceptor cell death in retinal degeneration

PurposeTo explore the expression and role of lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) in retinal degeneration.MethodsThe retinal degeneration of BALB/c mice was induced by light exposure. BV2 cells were activated by LPS stimulation. Retinas or BV2 cells were pretreated with LOX-1 neutralizing antibody or Polyinosinic acid (PolyI) (the inhibitor of LOX-1) before light damage (LD) or LPS stimulation. LOX-1, TNF-α, IL-1β, CCL2 and NF-κB expression were detected in retinas or BV2 cells by real-time RT-PCR, western blot or ELISA. Histological analyses of retinas were performed. Photoreceptor cell death was assessed by TUNEL assay in retinas or by flow cytometry in 661W cells cultured in microglia-conditioned medium.ResultsPhotoreceptor cell death and elevated expression of LOX-1 were induced by LD in retinas of BALB/c mice. LOX-1 neutralizing antibody or PolyI pretreatment significantly reduced the elevated expression of LOX-1, TNF-α, IL-1β, CCL2 and p-NF-κB caused by LD in retinas. Inhibition of LOX-1 by LOX-1 neutralizing antibody or PolyI significantly reduced photoreceptor cell death induced by LD in retinas. Elevated levels of TNF-α, IL-1β and CCL2 caused by LPS were down-regulated by inhibition of LOX-1 in BV2 cells. Inhibition of LOX-1 reduces microglial neurotoxicity on photoreceptors.ConclusionsLOX-1 expression is increased in light induced retinal degeneration, what’s more, inhibition of LOX-1 prevents inflammation and photoreceptor cell death in retinal degeneration and reduces microglial neurotoxicity on photoreceptors. Therefore, LOX-1 can be used as a potential therapeutic target for such retinal degeneration diseases.     

Mode of cell death after acetaminophen overdose in mice: apoptosis or oncotic necrosis?

Acetaminophen (AAP) overdose can cause severe liver injury and liver failure in experimental animals and humans. Recently, several authors proposed that apoptosis might be a major mechanism of cell death after AAP treatment. To address this controversial issue, we evaluated a detailed time course of liver injury after AAP (300 mg/kg) in fasted C3Heb/FeJ mice. Apoptotic hepatocytes were quantified in H&E-stained liver sections using morphologic criteria (cell shrinkage, chromatin condensation and margination, and apoptotic bodies). The number of apoptotic hepatocytes remained at baseline (0.2 +/- 0.1 cells/10 high-power fields [HPF]) up to 2 h after AAP administration. However, between 3 and 24 h, apoptotic cell death increased significantly, e.g., 6.3 +/- 0.8 cells/10 HPF at 6 h. Despite the increase in the number of hepatocytes meeting the morphological criteria of apoptosis, this cell fraction remained well below 1% of all parenchymal cells. No evidence for caspase-3 processing or increase in enzyme activity was detected at any time. These results were compared to the overall percent of necrotic cells in liver sections. Confluent areas of centrilobular necrosis were estimated to involve 40-60% of all hepatocytes between 3 and 24 h after AAP administration. These numbers correlated with the increase in plasma alanine aminotransferase activities, which reached a peak level of 5900 +/- 1350 U/l at 24 h. A similar result was obtained with higher doses of AAP and with the use of fed animals. Thus, oncotic necrosis and not apoptosis is the principal mechanism of liver-cell death after AAP overdose in vivo.     

Nanomaterial-induced cell death in pulmonary and hepatic cells following exposure to three different metallic materials: The role of autophagy and apoptosis

Autophagy is the catabolic process involving the sequestration of the cytoplasm within double-membrane vesicles, which fuse with lysosomes to form autolysosomes in which autophagic targets are degraded. Since most endocytic routes of nanomaterial uptake converge upon the lysosome and the possibility that autophagy induction by NMs may be an attempt by the cell to self-preserve following the external challenge, this study investigated the role of autophagy following exposure to a panel of widely used metal-based NMs with high toxicity (Ag and ZnO) or low toxicity (TiO₂) in a pulmonary (A549) and hepatic (HepG2) cell line. The in vitro exposure to the Ag and ZnO NMs resulted in the induction of both apoptosis and autophagy pathways in both cell types. However, the progression of autophagy was blocked in the formation of the autolysosome, which coincided with morphologic changes in the actin cytoskeleton. This response was not observed following the exposure to low-toxicity TiO₂ NMs. Overall, the results show that high toxicity NMs can cause a dysfunction in the autophagy pathway which is associated with apoptotic cell death.     

In vitro toxicity of tetrabromobisphenol-A on cerebellar granule cells: cell death, free radical formation, calcium influx and extracellular glutamate.

Tetrabromobisphenol-A (TBBPA) is one of the worlds most widely used brominated flame retardant. The present study reports effects of TBBPA on primary cultures of cerebellar granule cells (CGC). Using the trypan blue exclusion assay, we show that TBBPA induces death of CGC at low micro molar concentrations. Cell death was reduced by the NMDA receptor antagonist MK-801 (3 microM), the antioxidant vitamin E (50 microM), and in calcium-free buffer. We further demonstrate that TBBPA's toxicity was accompanied by apoptosis-like nuclear shrinkage, chromatin condensation, and DNA fragmentation. Other hallmarks of apoptosis such as caspase activity were, however, absent, indicating an atypical form of apoptosis. TBBPA increased intracellular free calcium in a concentration-dependent manner. TBBPA also induced an increase in extracellular glutamate in a time-dependent manner. TBBPA gave a concentration-dependent increase information reactive oxygen species (ROS) of measured with 2,7-dichlorofluorescein diacetate. The ROS formation was inhibited by the extracellular signal-regulated protein kinase (ERK) inhibitor U0126 (10 microM), the tyrosine kinase inhibitor erbstatin-A (25 microM), eliminating calcium from the buffer and by the superoxide dismutase inhibitor diethyldithio-carbamic acid (DDC, 100 microM). Further analysis with Western blot confirmed phosphorylation of ERK1/2 after exposure to TBBPA. We found that TBBPA induces ROS formation, increases intracellular calcium, extracellular glutamate, and death of CGC in vitro at concentrations comparable to those of polychlorinated biphenyl. These findings implicate TBBPA as a predicted environmental toxin and bring out the importance of awareness of its hazardous effects.     

Low concentrations of paraquat induces early activation of extracellular signal-regulated kinase 1/2, protein kinase B, and c-Jun N-terminal kinase 1/2 pathways: role of c-Jun N-terminal kinase in paraquat-induced cell death.

Paraquat is a herbicide with a potential risk to induce parkinsonism due to its demonstrated neurotoxicity and its strong structural similarity to 1-methyl-4-phenylpyridinium (MPP(+)), a well-known neurotoxin which causes a clinical syndrome similar to Parkinson's disease (PD). However, at present very little is known about the signaling pathways activated by paraquat in any cell system. In this study, we have investigated the effect of paraquat on extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK), and protein kinase B (PKB) activation in E18 cells. Low concentrations of paraquat stimulated very early increases in ERK1/2, JNK1/2, and PKB phosphorylation. The phosphatidylinositol 3-kinase (PI-3K) inhibitors wortmannin and LY 294002 (2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one) inhibited early paraquat-induced increases in PKB phosphorylation. Furthermore, early paraquat-mediated increases in ERK1/2 activation were sensitive to the mitogen-activated protein kinase kinase 1 (MEK1) inhibitor PD 98059 (2'-amino-3'-methoxyflavone), whereas JNK1/2 responses were blocked by the JNK1/2 inhibitor SP 600125 (anthra[1-9-cd]pyrazol-6(2H)-one). Pretreatment with wortmannin, LY 294002, or PD 98059 had no effect on paraquat cell death in E18 cells. In contrast, SP 600125 significantly decreased paraquat-induced cell death in E18 cells. In conclusion, we have shown that low concentrations of paraquat stimulate robust very early increases in ERK1/2, JNK1/2, and PKB phosphorylation in E18 cells. Furthermore, the data presented clearly suggest that inhibition of the JNK1/2 pathway protects E18 cells from paraquat-induced cell death and support the fact that inhibition of early activation of JNK1/2 can constitute a potential strategy in PD treatment.     

Sense and sensibility: the use of cell death biomarker assays in high-throughput anticancer drug screening and monitoring treatment responses

Cell-based screening allows identification of biologically active compounds, for example, potential anticancer drugs. In this review, various screening assays are discussed in terms of what they measure and how this affects interpretation and relevance. High-throughput (HT) assays of viability based on the reduction of exogenous substrates do not always reflect viability or cell number levels. Membrane integrity assays can be used for HT quantification of cell death, but are non-specific as to the death mode. Several HT assays monitor end point apoptosis. Screening libraries at a single concentration (micromolar) can prevent detection of potent apoptosis inducers, as high concentrations may induce mainly necrosis. Using monolayer cultures limits the significance of cell-based screening as the properties of monolayer cells differ from tumours in vivo. Spheroid cultures are more physiological, but are impractical for screening by conventional methods. The authors have developed an assay quantifying accumulation of a caspase-cleaved protein specific for epithelial cells. It provides an integrated measure of apoptosis in two- and three-dimensional cultures and can be used as a blood biomarker assay for tumour apoptosis in vivo.     

Lansoprazole increases testosterone metabolism and clearance in male Sprague-Dawley rats: implications for Leydig cell carcinogenesis

Leydig cell tumours (LCTs) are frequently observed during rodent carcinogenicity studies, however, the significance of this effect to humans remains a matter of debate. Many chemicals that produce LCTs also induce hepatic cytochromes P450 (CYPs), but it is unknown whether these two phenomena are causally related. Our aim was to investigate the existence of a liver-testis axis wherein microsomal enzyme inducers enhance testosterone metabolic clearance, resulting in a drop in circulating hormone levels and a consequent hypertrophic response from the hypothalamic-pituitary-testis axis. Lansoprazole was selected as the model compound as it induces hepatic CYPs and produces LCTs in rats. Male Sprague-Dawley rats were dosed with lansoprazole (150 mg/kg/day) or vehicle for 14 days. Lansoprazole treatment produced effects on the liver consistent with an enhanced metabolic capacity, including significant increases in relative liver weights, total microsomal CYP content, individual CYP protein levels, and enhanced CYP-dependent testosterone metabolism in vitro. Following intravenous administration of [14C]testosterone, lansoprazole-treated rats exhibited a significantly smaller area under the curve and significantly higher plasma clearance. Significant reductions in plasma and testicular testosterone levels were observed, confirming the ability of this compound to perturb androgen homeostasis. No significant changes in plasma LH, FSH, or prolactin levels were detected under our experimental conditions. Lansoprazole treatment exerted no marked effects on testicular testosterone metabolism. In summary, lansoprazole treatment induced hepatic CYP-dependent testosterone metabolism in vitro and enhanced plasma clearance of radiolabelled testosterone in vivo. These effects may contribute to depletion of circulating testosterone levels and hence play a role in the mode of LCT induction in lansoprazole-treated rats.     

The metalloporphyrin FeTPPS but not by cyclosporin A antagonizes the interaction of peroxynitrate and hydrogen peroxide on cardiomyocyte cell death

The objective of this study was to determine whether the metalloporphyrin, 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrinato iron (III) chloride (FeTPPS), antagonized the effect of peroxynitrite, oxygen-free radicals, and the combination of the two, on cardiomyocyte cell viability. We further sought to compare the effects of FeTPPS to an inhibitor of the mitochondrial transmembrane permeability transition pores (PTP)—cyclosporin A. Cardiomyocytes from embryonic chick heart were treated with 3-morpholinosydnonimine (SIN-1), which decomposes to liberate NO and superoxide anion (O₂ ⁻) which in turn generates peroxynitrite. FeTPPS antagonized cell death induced by either SIN-1 or H₂O₂. The combination of H₂O₂ plus SIN-1 further enhanced the amount of cell death over SIN-1 alone. FeTPPS rescued cells from almost complete cell death with the combination of SIN-1 plus H₂O₂. SIN-1 induced cardiac protein nitration, including mitochondrial proteins as demonstrated by Western blotting with nitrotyrosine-specific antibodies. FeTPPS reduced cellular protein nitration. SIN-1-induced loss of mitochondrial transmembrane permeability transition pores potential was visualized with fluorescent dye staining and was reversed by FeTPPS. In contrast, the mitochondrial PTP blocker cyclosporin A did not alter SIN-1-induced cell death. In summary, these data demonstrate the enhanced cellular lethality of the combination of peroxynitrite and reactive oxygen species from hydrogen peroxide. A mitochondrial death pathway was implicated as nitration of mitochondrial proteins was induced by peroxynitrite that also induced a loss of ΔΨm that was prevented by FeTPPS. In contrast, cyclosporin did not antagonize the effects of SIN-1. The ability of FeTPPS to reduce reactive nitrogen-induced cell death, and protein nitration suggests that FeTPPS is a useful agent to maintain cell viability and is better than cyclosporin in this situation.     

程序性死亡因子-1、程序性死亡配体-1、TNF家族B细胞活化因子-R在弥漫性大B细胞淋巴瘤组织中的表达

目的 分析程序性死亡因子-1(programmed death factor-1,PD-1)、程序性死亡配体-1(programmed death-ligand-1,PD-L1)、TNF家族B细胞活化因子-R(B cell-activating factor-R belonging to the TNF family,...     

正常人肝细胞和肝癌细胞对力达霉素诱导的有丝分裂性细胞死亡的差异

[摘要]目的：探讨力达霉素（lidamycin, LDM）诱导人肝癌BEL-7402和正常人肝L-02细胞出现的有丝分裂性细胞死亡的差异。方法：采用MTT法观察LDM对BEL-7402和L-02细胞生长曲线的影响;使用Giemsa染色和流式细胞术观察有丝分裂性细胞死亡特征;用Western blot法检测蛋白表达变化。结果：LDM抑制BEL-7402和L-02细胞的生长,二者均表现出有丝分裂性细胞死亡的特征,即细胞体积增大、G2/M期阻滞、出现多核化,但BEL-7402细胞对LDM更敏感。在LDM处理的BEL-7402和L-02细胞中,与凋亡相关的Bax和Smac的蛋白表达水平没有增加,caspase-3和caspase-9未被活化,但L-02细胞的Akt通路被激活。结论：人正常L-02细胞对LDM引起的有丝分裂性细胞死亡明显低于人肝癌BEL-7402细胞,对LDM的反应敏感性存在差异的原因可能与Akt信号通路有关。     

Doxorubicin,mesenchymal stem cell toxicity and antitumour activity: implications for clinical use

Objectives

The use of doxorubicin, an antineoplastic medication used for the treatment of cancers via mechanisms that prevent replication of cells or lead to their death, can result in damage to healthy cells as well as malignant. Among the affected cells are mesenchymal stem cells (MSCs), which are involved in the maintenance and repair of tissues in the body. This review explores the mechanisms of biological effects and damage attributed to doxorubicin on MSCs. The PubMed database was used as a source of literature for this review.

Key findings

Doxorubicin has the potential to lead to significant and irreversible damage to the human bone marrow environment, including MSCs. The primary known mechanism of these changes is through free radical damage and activation of apoptotic pathways. The presence of MSCs in culture or in vivo appears to either suppress or promote tumour growth. Interactions between doxorubicin and MSCs have the potential to increase chemotherapy resistance.

Summary

Doxorubicin‐induced damage to MSCs is of concern clinically. However, MSCs also have been associated with resistance of tumour cells to drugs including doxorubicin. Further studies, particularly in vivo, are needed to provide consistent results of how the doxorubicin‐induced changes to MSCs affect treatment and patient health.