Zinc, an essential trace element, is critical for maintaining the normal cardiac structure and function by regulating oxidative stress, mitochondrial homeostasis, and intracellular signaling pathways. Zinc homeostasis is maintained by a tightly coordinated network of zinc transporters and zinc-responsive sensors. Zinc transporters are classified into two functionally opposing families: the SLC39A/ZIP family imports zinc into the cytosol, whereas the SLC30A/ZnT family promotes zinc efflux from the cytosol. Dys-expression or dys-functions of these transporters is implicated in the pathology of various cardiovascular diseases, including ischemia/reperfusion (I/R) injury, diabetic cardiomyopathy (DCM)), hypertrophy, and atrial fibrillation. Key transporters such as ZIP2, ZIP7, ZIP8, ZIP13, ZIP14, ZnT1, and ZnT5 perform distinct and context-dependent functions in cardiac physiology and pathpysiology. In addition, zinc-responsive sensors such as PIAS3 sense fluctuations in intracellular free zinc levels and rapidly trigger adaptive transcriptional programs that modulate expression of zinc transporters to restore zinc homeostasis. This review summarizes current advances in the understanding of zinc dyshomeostasis in cardiac pathophysiology, and highlights the emerging roles of zinc transporters as potential modulators and therapeutic targets in cardiovascular diseases.

Aims: While ferroptosis is involved in the pathogenesis of myocardial ischemia/reperfusion (I/R) injury, the exact mechanism underlying the induction of ferroptosis by I/R remains elusive. Since downregulation of Zrt, Irt-like protein 13 (ZIP13) plays a role in I/R injury by targeting mitochondria, we hypothesized that ZIP13 downregulation during I/R leads to ferroptosis through a mitochondria-dependent mechanism. Results: ZIP13 cKO (cardiac-specific conditional knockout) induced ferroptosis and suppressed mitochondrial iron-sulfur cluster (ISC) biosynthesis. ZIP13 cKO also reduced glutathione levels as well as solute carrier family 7 member 11 (SLC7A11) expression. Moreover, cKO increased mitochondrial Fe2+ levels. Similar to the action of cKO, I/R led to ZIP13 downregulation, ferroptosis, mitochondrial Fe2+ accumulation, and suppression of ISC biosynthesis. In support, cKO of ZIP13 aggravated I/R-induced ferroptosis and mitochondrial Fe2+ accumulation. In contrast, ZIP13 overexpression prevented I/R-induced ferroptosis, mitochondrial Fe2+ accumulation, and suppression of ISC biosynthesis. Finally, ferrostatin-1, a ferroptosis inhibitor, alleviated I/R-induced ferroptosis as well as cardiac injury in cKO mice. Innovation: This study proposes a previously unknown mechanism by which ZIP13 downregulation contributes to ferroptosis in the setting of myocardial I/R. Conclusions: These findings highlight that ZIP13 downregulation at reperfusion triggers ferroptosis by suppressing the mitochondrial ISC biosynthesis followed by mitochondrial Fe2+ accumulation. Downregulation of SLC7A11 may also contribute to the action of ZIP13 downregulation. Antioxid. Redox Signal. 43, 328-344.

Immune checkpoint inhibitors (ICIs) are emerging promising agents for the treatment of patients with esophageal squamous cell carcinoma (ESCC), however, there are only a small proportion respond to ICI therapy. Therefore, selecting candidate patients who will benefit the most from these drugs is critical. However, validated biomarkers for predicting immunotherapy response and overall survival are lacking. As the fundamental principle of ICI therapy is T cell-mediated tumor killing (TTK), we aimed to develop a unique TTK-related gene prognostic index (TTKPI) for predicting survival outcomes and responses to immune-based therapy in ESCC patients. Transcriptomic and clinical information of ESCC patients were from the GSE53625, GSE53624, GSE47404 and TCGA datasets. TTK-related genes were from the TISIDB database. The LASSO Cox regression model was employed to create the TTKPI. The prediction potential of the TTKPI was evaluated using the KM curve and time-dependent ROC curve analysis. Finally, the relationship between TTKPI and immunotherapy efficacy was investigated in clinical trials of ICIs (GSE91061, GSE135222, IMvigor210 cohort). The role of KIF11 in accelerating tumor progression was validated via a variety of functional experiments, including western blot, CCK-8, colony formation, wound healing scratch, and xenograft tumor model. The KIF11 expression was detected by multiplex fluorescent immunohistochemistry on tissue microarray from ESCC patients. We constructed the TTKPI based on 8 TTK-related genes. The TTKPI low-risk patients exhibited better overall survival. TTKPI was significantly and positively correlated with the main immune checkpoint molecules levels. Furthermore, the low-risk patients were more prone to reap the benefits of immunotherapy in the cohort undergoing anti-PD-L1 therapy. Moreover, we performed functional experiments on KIF11, which ranked as the most significant prognostic risk gene among the 8 TTK-related genes. Our findings identified that KIF11 knockdown significantly hindered cell proliferation and mobility in ESCC cells. The KIF11 expression was negatively related with CD8+ T cell infiltration in ESCC patient samples. The TTKPI is a promising biomarker for accurately determining survival and predicting the effectiveness of immunotherapy in ESCC patients. This risk indicator can help patients receive timely and precise early intervention, thereby advancing personalized medicine and facilitating precise immuno-oncology research. KIF11 plays a crucial role in driving tumor proliferation and migration and may act as a potential tumor biomarker of ESCC.

Alterations in zinc transporter expression in response to zinc loss protect cardiac cells from ischemia/reperfusion (I/R) injury. However, the underlying molecular mechanisms how cardiac cells sense zinc loss remains unclear. Here, we found that zinc deficiency induced ubiquitination and degradation of the protein inhibitor of activated STAT3 (PIAS3), which can alleviate myocardial I/R injury by activating STAT3 to promote the expression of ZIP family zinc transporter genes. The RING finger domain within PIAS3 is vital for PIAS3 degradation, as PIAS3-dRing (missing the RING domain) and PIAS3-Mut (zinc-binding site mutation) were resistant to degradation in the setting of zinc deficiency. Meanwhile, the RING finger domain within PIAS3 is critical for the inhibition of STAT3 activation. Moreover, PIAS3 knockdown increased cardiac Zn2+ levels and reduced myocardial infarction in mouse hearts subjected to I/R, whereas wild-type PIAS3 overexpression, but not PIAS3-Mut, reduced cardiac Zn2+ levels, and exacerbated myocardial infarction. These findings elucidate a unique mechanism of zinc sensing, showing that fast degradation of the zinc-binding regulatory protein PIAS3 during zinc deficiency can correct zinc dyshomeostasis and alleviate reperfusion injury.

目的:通过深入挖掘肿瘤公共数据库中的基因信息,分析ZIP转运蛋白家族成员在肝细胞癌(hepa-tocellular carcinoma,HCC)中的表达情况及与临床预后的相关性.方法:通过Oncomine和UCSC Xena等肿瘤学公共数据库对ZIP转运蛋白在HCC中的表达情况进行分析;使用cBioPortal数据库探究ZIP家族基因在HCC样本中的遗传改变;利用Kaplan-Meier plotter数据库分析ZIP家族成员表达水平与HCC患者临床预后的关系,探讨其潜在的临床意义.结果:HCC组织中ZIP1、ZIP6和ZIP10 mRNA表达水平明显上调,而ZIP5、ZIP8、ZIP9和ZIP14 mRNA表达水平却明显低于正常组织.进一步分析发现,基因拷贝数改变是引起ZIP1和ZIP14异常表达的重要原因,并且ZIP1扩增的患者的总生存期(OS)显著缩短.Kaplan-Meier分析结果表明,ZIP1、ZIP6和ZIP10高表达的HCC患者,其预后较差,而ZIP2、ZIP11和ZIP12高表达则提示HCC患者预后良好.此外,ZIP表达水平在携带不同类型危险因素的HCC患者预后中具有差异性,例如ZIP4基因高表达可能与肝炎病毒阴性患者的不良预后相关,而ZIP14基因高表达的肝炎病毒阴性或饮酒的HCC患者则预后良好.结论:ZIP转运蛋白表达与肝细胞癌患者临床预后相关,并且具有一定的差异性.

Zinc homeostasis has been known to play a role in myocardial ischemia/reperfusion (I/R) injury, but the precise molecular mechanisms regulating the expression of ZIP transporters during reperfusion are still unclear. The aim of this study was to determine whether ER Stress/CaMKII/STAT3 pathway plays a role in the regulation of cellular zinc homeostasis. Zinc deficiency increased mRNA and protein expressions of the ER stress relevant markers Chop and Bip, and STAT3 phosphorylation in H9c2 or HL-1 cells, an effect that was abolished by ZnCl2. ER calcium concentration [(Ca2+)(ER)] was decreased and cytosolic calcium concentration [(Ca2+)(I)] was increased at the condition of normoxia or ischemia/reperfusion, indicating that zinc deficiency triggers ER stress and Ca2+ leak. Further studies showed that upregulation of STAT3 phosphorylation was reversed by Ca2+ chelator, indicating that intracellular Ca2+ is important for zinc deficiency-induced STAT3 activation. In support, zinc deficiency enhanced ryanodine receptors (RyR), a channel in the ER that mediate Ca2+ release, and Ca2+-calmodulin-dependent protein kinase (CaMKII) phosphorylation, implying that zinc deficiency provoked Ca2+ leak from ER via RyR and p-CaMKII is involved in STAT3 activation. Moreover, inhibition of STAT3 activation blocked zinc deficiency induced ZIP9 expression, and resulted in increased Zn2+ loss in cardiomyocytes, further confirming that STAT3 activation during reperfusion promotes the expression of ZIP9 zinc transporter to correct the imbalance in zinc homeostasis. In addition, suppressed STAT3 activation aggravated reperfusion injury. These data suggest that the ER Stress/CaMKII/STAT3 axis may be an endogenous protective mechanism, which increases the resistance of the heart to I/R.

目的:探讨锌转运体ZIP13(SLC39A13)在肝脏缺血再灌注损伤中的作用及机制.方法:通过结扎肝左叶和肝中叶的门静脉及肝动脉共干,建立小鼠在体肝脏缺血再灌注模型,将小鼠分组如下:(1)ZIP13fl/fl-Sham组、ZIP13fl/fl+I1R12组和ZIP13LKO+I1R12组.(2)ZIP13fl/fl-Sham组、ZIP13fl/fl+I1R24组和ZIP13LKO+I1R24组.(3)Vector-Sham组、Vector+I1R12组和ZIP13OE+I1R12组.(4)Vector-Sham组、Vector+I1R24组和ZIP13OE+I1R24组,上述每组小鼠3～4只.采用电感耦合离子发射光谱仪(ICP-OES)测量肝组织的锌含量;试剂盒检测丙氨酸转氨酶(ALT)和门冬氨酸转氨酶(AST)水平;HE染色观察病理学改变;原位末端转移酶标记法(TUNEL法)检测细胞凋亡;Western印迹检测CHOP、GRP78和凋亡蛋白表达.结果:与ZIP13fl/fl小鼠相比,ZIP13LKO小鼠肝脏中ZIP13表达明显下降(t=6.26,P<0.01),而与Vector感染对照小鼠相比,ZIP13OE小鼠肝脏ZIP13蛋白表达明显增加(t=4.17,P<0.05).与ZIP13fl/fl-Sham组相比,ZIP13fl/fl+I1R12组血清ALT、AST水平升高(t=11.43、13.70,均P<0.001),ZIP13fl/fl+I1R24组小鼠肝组织锌含量明显降低(t=13.49,P<0.001),内质网应激蛋白CHOP和GRP78表达增强(t=4.76、4.54,均P<0.05),凋亡蛋白Cleaved Caspase9和Cleaved Caspase3表达升高(t=4.56、3.73,均P<0.05).与相应的ZIP13fl/fl缺血再灌注组相比,ZIP13LKO+I1R12组血清ALT、AST水平进一步升高(t=2.95、3.20,均P<0.05),ZIP13LKO+I1R24组肝组织中锌含量显著降低(t=3.29,P<0.05),内质网应激蛋白表达上调(t=2.60、2.98,均P<0.05),凋亡蛋白表达也明显升高(t=3.44、2.49,均P<0.05).与相应的Vector感染缺血再灌注组相比,ZIP13OE+I1R12组血清ALT、AST水平明显下降(t=3.69、4.26,均P<0.05),ZIP13OE+I1R24组小鼠肝组织中锌含量增加(t=3.88,P<0.05),内质网应激蛋白表达下降(t=3.47、2.88,均P<0.05),凋亡蛋白的表达水平也呈现降低(t=3.02、2.96,均P<0.05).结论:肝脏缺血再灌注时,ZIP13通过维持肝脏锌稳态,减轻内质网应激和细胞凋亡.

BACKGROUND Phase I clinical trials play an important role in the follow-up clinical trials and even the drug registration and marketing. However, the screening success ratio in phase I clinical trials is low, and the screening process of the trials consumes a significant amount of human and material resources, but the results are unsatisfactory. At present, there is no large sample data analysis for screening failure in phase I clinical trials. It is therefore urgent to find the reasons for screening failure in phase I clinical trials. METHODS A total of 1,058 healthy volunteers who failed the screening in 11 phase I clinical trials were retrospectively collected from October 2018 to June 2021 in Cangzhou Central Hospital. Data on all participants who failed screening for the study were analyzed (descriptive analysis) and reasons for their non-randomization were classified, as well as the differences of main screening failures between four years. RESULTS A total of 1,466 healthy volunteers were enrolled in the 11 trials, and among them 1,058 subjects failed the screening. The total screening success ratio of our study was only 27.8%, the highest being 38.5% and the lowest being 18.2%. The top 3 reasons for non-randomization were abnormalities in blood biochemistry tests (23.3%), vital sign examination (19.3%), and electrocardiogram (ECG) (16.6%). Abnormal blood biochemistry was the main reason between 2019 and 2021, except for 2018 in which it was the second reason. CONCLUSIONS Screening failure is a burdensome issue which various clinical trial sites must contend with. Investigators can still take some effective measures by strengthening the in-depth understanding of informed consent, paying attention to the quality of test samples, a correcting definition of no clinical significance (NCS). Also, low-cost and non-invasive examinations can be arranged first to better protect the volunteers and reduce the screening costs of clinical trials. To our delight, we find people's attention to the annual physical examination may help to screen healthy volunteers. Overall, this study shows that it is crucial and professional to develop a screening plan to minimize the resultant impact on timelines and budgets of phase I clinical trials enrolling healthy volunteers.

Whereas elimination of damaged mitochondria by mitophagy is proposed to be cardioprotective, the regulation of mitophagy at reperfusion and the underlying mechanism remain elusive. Since mitochondrial Zn2+ may control mitophagy by regulating mitochondrial membrane potential (MMP), we hypothesized that the zinc transporter ZIP7 that controls Zn2+ levels within mitochondria would contribute to reperfusion injury by regulating mitophagy. Mouse hearts were subjected to ischemia/reperfusion in vivo. Mitophagy was evaluated by detecting mitoLC3II, mito-Keima, and mitoQC. ROS were measured with DHE and mitoB. Infarct size was measured with TTC staining. The cardiac-specific ZIP7 conditional knockout mice (ZIP7 cKO) were generated by adopting the CRISPR/Cas9 system. Human heart samples were obtained from donors and recipients of heart transplant surgeries. KO or cKO of ZIP7 increased mitophagy under physiological conditions. Mitophagy was not activated at the early stage of reperfusion in mouse hearts. ZIP7 is upregulated at reperfusion and ZIP7 cKO enhanced mitophagy upon reperfusion. cKO of ZIP7 led to mitochondrial depolarization by increasing mitochondrial Zn2+ and, accumulation of PINK1 and Parkin in mitochondria, suggesting that the decrease in mitochondrial Zn2+ in response to ZIP7 upregulation resulting in mitochondrial hyperpolarization may impede PINK1 and Parkin accumulation in mitochondria. Notably, ZIP7 is markedly upregulated in cardiac mitochondria from patients with heart failure (HF), whereas mitochondrial PINK1 accumulation and mitophagy were suppressed. Furthermore, ZIP7 cKO reduced mitochondrial ROS generation and myocardial infarction via a PINK1-dependet manner, whereas overexpression of ZIP7 exacerbated myocardial infarction. Our findings identify upregulation of ZIP7 leading to suppression of mitophagy as a critical feature of myocardial reperfusion injury. A timely suppression of cardiac ZIP7 upregulation or inactivation of ZIP7 is essential for the treatment of reperfusion injury.

目的 探讨血府逐瘀胶囊预处理对大鼠心肌缺血/再灌注(I/R)损伤的保护作用及机制.方法 Wistar大鼠随机分为假手术组、缺血/再灌注组(I/R组)、血府逐瘀胶囊组(Xuefu组)、血府逐瘀胶囊+LY294002组(XL组)、血府逐瘀胶囊+PD98059组(XP组).血府逐瘀胶囊预处理3 d后用全心缺血/再灌注的方式构建大鼠体外I/R模型,用TTC染色法检测心肌梗死面积,用PowerLab系统测量心脏功能,用Oxygraph-2k检测大鼠心肌线粒体呼吸功能和氧化磷酸化水平,用Western blotting技术检测大鼠心肌组织中丝氨酸-苏氨酸蛋白激酶(Akt)和细胞外信号调节激酶(ERK)磷酸化水平.结果 I/R组和Xuefu组的心肌梗死面积分别为(73.57±11.33)％,(37.44±4.64)％;假手术组、I/R组和Xuefu组左心室发展压(LVDP)比值分别为(71.31±8.31)％,(20.37±3.51)％和(32.36±5.82)％;左心室内压最大上升速率(+dp/dtmax)比值分别为(74.83±10.92)％,(15.20±4.82)％和(26.54±4.54)％;左室内压最大下降速率(-dp/dtmax)比值分别为(74.71±12.87)％,(18.86±4.95)％和(32.22±6.71)％;线粒体复合体 Ⅰ 氧化磷酸化水平分别为(131.05±21.11),(34.58±9.88)和(71.64±28.99)pmol·s-1·mL-1;线粒体复合体Ⅰ+Ⅱ氧化磷酸化水平分别为(162.71±13.77),(68.51±18.32)和(110.32±19.38)pmol·s-1·mL-1;呼吸控制率(RCR)分别为2.36±0.30,1.43±0.22和2.05±0.20;p-Akt(Ser473)的相对表达分别为0.53±0.22,0.96±0.11和1.20±0.12;p-ERK的相对表达分别为0.55±0.18,0.80±0.18和1.16±0.11.I/R组的上述指标与Sham组和Xuefu组比较,差异均有统计学意义(P<0.05,P<0.01).Xuefu组和XL组的心肌梗死面积分别为(35.30±7.01)％和(51.21±5.87)％;Xuefu组和XP组的线粒体复合体Ⅰ氧化磷酸化水平分别为(66.04±17.97)和(34.83±8.58)pmol·s-1·mL-1;线粒体复合体Ⅰ+Ⅱ氧化磷酸化水平分别为(104.39±18.05)和(70.23±16.22)pmol·s-1·mL-1;RCR分别为2.08±0.23和1.63±0.24.Xuefu组的上述指标与XL组、XP组相比较,差异均有统计学意义(P<0.05或P<0.01).结论 血府逐瘀胶囊预处理通过PI3K/Akt和ERK通路减轻大鼠心肌缺血/再灌注损伤.

Zinc transporters have been found to be associated with the pathogenesis of numerous human diseases including cancer. As the most lethal gynecologic malignancy, ovarian cancer is characterized by rapid progression and widespread metastases. However, the function and underlying mechanism of zinc transporters in ovarian cancer metastasis remain unclear. The relationship between zinc transporter gene expressions and clinical outcomes of ovarian cancer was assessed with the online database Kaplan-Meier plotter ( http://kmplot.com/analysis/ ). Immunohistochemistry was performed to investigate the prognostic importance of ZIP13. The expression of ZIP13 in ovarian cancer cell lines was depleted to explore its effect on proliferation, adhesion, migration, and invasion both in vitro and in vivo assays. RNA-Seq, quantitative RT-PCR, and western blot analysis were performed to explore ZIP13-regulated downstream target genes. The expressions of several zinc transporters were highly associated the clinical outcomes of ovarian cancer patients. Among them, high ZIP13 expression was an independent prognostic factor for poor survival in patients with ovarian cancer. ZIP13 knockout suppressed the malignant phenotypes of ovarian cancer cells both in vitro and in vivo. Further investigation revealed that ZIP13 regulated intracellular zinc distribution and then affected the expressions of genes involved in extracellular matrix organization and cytokine-mediated signaling pathway. This led to the activation of Src/FAK pathway with increased expressions of pro-metastatic genes but decreased expressions of tumor suppressor genes. ZIP13 is shown to be a novel driver of metastatic progression by modulating the Src/FAK signaling pathway, which may serve as a promising biomarker for prognostic evaluation and targeted therapy in ovarian cancer.

While Zn2+ dyshomeostasis is known to contribute to ischemia/reperfusion (I/R) injury, the roles of zinc transporters that are responsible for Zn2+ homeostasis in the pathogenesis of I/R injury remain to be addressed. This study reports that ZIP13 (SLC39A13), a zinc transporter, plays a role in myocardial I/R injury by modulating the Ca2+ signaling pathway rather than by regulating Zn2+ transport. ZIP13 is downregulated upon reperfusion in mouse hearts or in H9c2 cells at reoxygenation. Ca2+ but not Zn2+ was responsible for ZIP13 downregulation, implying that ZIP13 may play a role in I/R injury through the Ca2+ signaling pathway. In line with our assumption, knockout of ZIP13 resulted in phosphorylation (Thr287) of Ca2+-calmodulin-dependent protein kinase (CaMKII), indicating that downregulation of ZIP13 leads to CaMKII activation. Further studies showed that the heart-specific knockout of ZIP13 enhanced I/R-induced CaMKII phosphorylation in mouse hearts. In contrast, overexpression of ZIP13 suppressed I/R-induced CaMKII phosphorylation. Moreover, the heart-specific knockout of ZIP13 exacerbated myocardial infarction in mouse hearts subjected to I/R, whereas overexpression of ZIP13 reduced infarct size. In addition, knockout of ZIP13 induced increases of mitochondrial Ca2+, ROS, mitochondrial swelling, decrease in the mitochondrial respiration control rate (RCR), and dissipation of mitochondrial membrane potential (ΔΨm) in a CaMKII-dependent manner. These data suggest that downregulation of ZIP13 at reperfusion contributes to myocardial I/R injury through activation of CaMKII and the mitochondrial death pathway.

Zinc is an essential element and serves as a structural or catalytic component in many proteins. Two families of transporters are involved in maintaining cellular zinc homeostasis: the ZIP (SLC39A) family that facilitates zinc influx into the cytoplasm, and the ZnT (SLC30A) family that facilitates zinc efflux from the cytoplasm. Zinc dyshomeostasis caused by the dysfunction of zinc transporters can contribute to the initiation or progression of various cancers, including prostate cancer, breast cancer, and pancreatic cancer. In addition, intracellular zinc fluctuations lead to the disturbance of certain signaling pathways involved in the malignant properties of cancer cells. This review briefly summarizes our current understanding of zinc dyshomeostasis in cancer, and discusses the potential roles of zinc or zinc transporters in cancer therapy.

The aim of the present study was to investigate the effect of zinc transporter Zip2 (SLC39A2) on mitochondrial respiration during myocardial ischemia/reperfusion (I/R) and the underlying mechanisms. An in vivo myocardial I/R model was established in mice by ligation of left anterior descending coronary artery. Cardiac zinc concentration was measured by inductively coupled plasma-optical emission spectrometer (ICP-OES), and the mitochondrial respiratory function and oxidative phosphorylation were determined by high-resolution respirometry (Oxygraph-2K). The phosphorylation levels of STAT3 and ERK in myocardial tissue were detected by Western blot. The results showed that, compared with the sham group, cardiac zinc concentration in myocardium was decreased in wild-type mice and further reduced in Zip2 knockout mice after I/R. Mitochondrial respiratory control rate (RCR) and oxidative phosphorylation were decreased in Zip2 knockout mice and worsened by I/R. Phosphorylation levels of STAT3 (Ser727) and ERK were significantly decreased in Zip2 knockout mice after I/R. In I/R myocardial tissue, STAT3 overexpression significantly improved the mitochondrial respiratory function, while STAT3 dominant negative mutant (STAT3 S727A) inhibited mitochondrial respiratory function. Moreover, the impairment of mitochondrial function by Zip2 knockout was reversed by STAT3 overexpression. These results suggest that Zip2 regulates mitochondrial respiration via phosphorylation of STAT3 during myocardial I/R, which may represent the underlying mechanism of Zip2 cardioprotection against I/R injury.

Abstract Background Hemophilia A, a bleeding disorder resulting from F8 mutations, can only be cured by gene therapy. A promising strategy is CRISPR-Cas9-mediated precise insertion of F8 in hepatocytes at highly expressed gene loci, such as albumin (Alb). Unfortunately, the precise in vivo integration efficiency of a long insert is very low (~ 0.1%). Results We report that the use of a double-cut donor leads to a 10- to 20-fold increase in liver editing efficiency, thereby completely reconstituting serum F8 activity in a mouse model of hemophilia A after hydrodynamic injection of Cas9-sgAlb and B domain-deleted (BDD) F8 donor plasmids. We find that the integration of a double-cut donor at the Alb locus in mouse liver is mainly through non-homologous end joining (NHEJ)-mediated knock-in. We then target BDDF8 to multiple sites on introns 11 and 13 and find that NHEJ-mediated insertion of BDDF8 restores hemostasis. Finally, using 3 AAV8 vectors to deliver genome editing components, including Cas9, sgRNA, and BDDF8 donor, we observe the same therapeutic effects. A follow-up of 100 mice over 1 year shows no adverse effects. Conclusions These findings lay the foundation for curing hemophilia A by NHEJ knock-in of BDDF8 at Alb introns after AAV-mediated delivery of editing components.

Although zinc homeostasis has been demonstrated to play a role in myocardial ischemia/reperfusion (I/R) injury, the roles of zinc transporters that are critical for zinc homeostasis in I/R injury are poorly understood. The purpose of this study was to test if Zip2, an important zinc importer, plays a role in I/R injury in mouse hearts and explore the mechanism by which Zip2 expression is regulated. Zip2 expression was increased at reperfusion in in vivo mouse hearts, an effect that was abolished by ZnCl2, indicating Zip2's attempt to compensate for zinc loss at reperfusion. Further studies showed that upregulation of Zip2 expression was reversed by either pharmacological or genetic inhibition of signal transducers and activators of transcription 3 (STAT3), whereas STAT3 overexpression increased Zip2 expression, indicating that STAT3 accounts for Zip2 upregulation. In support., reperfusion enhanced STAT3 phosphorylation (Tyr(705)), which was blocked by ZnCl2, implying that STAT3 is activated in response to zinc loss. To determine the role of Zip2 in I/R injury, we assessed I/R injury by genetically disrupting Zip2 expression. Knockout of Zip2 genes (Zip(2+/-) and Zip2(-/-)) exacerbated I/R injury by increasing infarct size as well as the serum LDH, troponin I (cTnI), and CK-MB activities. In contrast, delivery of Zip2 genes reduced I/R injury. Delivery of STAT3 genes increased STAT3 phosphorylation and reduced I/R injury. However, delivery of the dominant negative STAT3 mutant did not reduce I/R injury. Moreover, delivery of STAT3 genes failed to reduce I/R injury in Zip2(-/-) mice. Zip2 upregulated upon re perfusion via STAT3 is cardioprotective and this upregulation may serve as an important intrinsic protective mechanism by which the heart is resistant to I/R injury. The factors involved in the zinc homeostasis (zinc and Zip2) are responsible STAT3 activation and its subsequent cardioprotective action.

Genetic variation (rs372883C/T) in the 3'-untranslated region of BTB and CNC homology 1 (BACH1) has been associated with pancreatic ductal adenocarcinoma (PDAC) risk in our previous genome-wide association study; however, the action roles of this genetic variation in PDAC remains unknown. Methods:BACH1 expression was measured by quantitative real-time PCR, Western blot and immunohistochemistry. The effects of BACH1 on cell proliferation and sensitivity to gemcitabine were examined by alteration of BACH1 expression in PDAC cells. Angiogenesis was determined in vitro using a human umbilical vein endothelial cell model. Reporter gene assays were conducted to compare the effects of microRNA-1257 on rs372883 variation. The associations between rs372883 variants and survival time in patients treated with gemcitabine were estimated by logistic regression. Results: We found substantially lower BACH1 expression in PDAC compared with normal pancreatic tissues and the rs372883T allele had significantly lower BACH1 levels than the rs372883C allele in both tumor and normal tissues. Knockdown of BACH1 expression provoked proliferation of PDAC cells and angiogenesis, which might result from upregulation of hemeoxygenase-1 that evokes oncogenic AKT and ERK signaling. The rs372883T>C change inhibits interaction of BACH1 with microRNA-1257, resulting in increased BACH1 expression. PDAC patients with the rs372883T allele were more resistant to gemcitabine and had shorter survival time compared with those with the rs372883C allele. Conclusion: These results shed light on the mechanism underlying the associations of BACH1 rs372883 variation with risk of developing PDAC and differential gemcitabine sensitivity in patients.

We have developed an improved episomal vector system for efficient generation of integration-free induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells. More recently, we reported that the use of an optimized CRISPR-Cas9 system together with a double-cut donor increases homology-directed repair-mediated precise gene knockin efficiency by 5- to 10-fold. Here, we report the integration of blood cell reprogramming and genome editing in a single step. We found that expression of Cas9 and KLF4 using a single vector significantly increases genome editing efficiency, and addition of SV40LT further enhances knockin efficiency. After these optimizations, genome editing efficiency of up to 40% in the bulk iPSC population can be achieved without any selection. Most of the edited cells show characteristics of iPSCs and genome integrity. Our improved approach, which integrates reprogramming and genome editing, should expedite both basic research and clinical applications of precision and regenerative medicine.

BACKGROUND: Although it is well known that remifentanil (Rem) elicits cardiac protection against ischemia/reperfusion (I/R) injury, the underlying mechanism remains unclear. This study tested if Rem can protect the heart from I/R injury by inhibiting endoplasmic reticulum (ER) stress through the maintenance of zinc (Zn2+) homeostasis. METHODS: Isolated rat hearts were subjected to 30 minutes of regional ischemia followed by 2 hours of reperfusion. Rem was given by 3 consecutive 5-minute infusions, and each infusion was followed by a 5-minute drug-free perfusion before ischemia. Total Zn2+ concentrations in cardiac tissue, cardiac function, infarct size, and apoptosis were assessed. H9c2 cells were subjected to 6 hours of hypoxia and 2 hours of reoxygenation (hypoxia/reoxygenation [H/R]), and Rem was given for 30 minutes before hypoxia. Metal-responsive transcription factor 1 (MTF1) overexpression plasmids were transfected into H9c2 cells 48 hours before hypoxia. Intracellular Zn2+ level, cell viability, and mitochondrial injury parameters were evaluated. A Zn2+ chelator N,N,N′,N′-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) or an ER stress activator thapsigargin was administrated during in vitro and ex vivo studies. The regulatory molecules related to Zn2+ homeostasis and ER stress in cardiac tissue, and cardiomyocytes were analyzed by Western blotting. RESULTS: Rem caused significant reversion of Zn2+ loss from the heart (Rem + I/R versus I/R, 9.43 ± 0.55 vs 7.53 ± 1.18; P < .05) by suppressing the expression of MTF1 and Zn2+ transporter 1 (ZnT1). The inhibited expression of ER stress markers after Rem preconditioning was abolished by TPEN. Rem preconditioning improved the cardiac function accompanied by the reduction of infarct size (Rem + I/R versus I/R, 21% ± 4% vs 40% ± 6%; P < .05). The protective effects of Rem could be reserved by TPEN and thapsigargin. Similar effects were observed in H9c2 cells exposed to H/R. In addition, MTF1 overexpression blocked the inhibitory effects of Rem on ZnT1 expression and ER stress at reoxygenation. Rem attenuated the collapse of mitochondrial membrane potential (ΔΨm) and the generation of mitochondrial reactive oxygen species by inhibiting ER stress via cardiac Zn2+ restoration (Rem + H/R versus H/R, 79.57% ± 10.62% vs 58.27% ± 4.32%; P < .05). CONCLUSIONS: Rem maintains Zn2+ homeostasis at reperfusion by inhibiting MTF1 and ZnT1 expression, leading to the attenuation of ER stress and cardiac injury. Our findings provide a promising therapeutic approach for managing acute myocardial I/R injury.