Clinical antiangiogenic effect of recombinant adenovirus-p53 combined with hyperthermia for advanced cancer

Objective： To assess the safety and clinical antiangiogenic effect of recombinant adenovirus-p53 （rAd-p53） combined with hyperthermia plus or not plus radiotherapy in advanced cancer. Methods： Expression of Vascular epithelial growth factor （VEGF） after intratumoral injection of rAd-p53 was assayed by immunohistochemistry （IHC） imaging. Forty-four patients with advanced cancer were enrolled into this clinical study. The patients were intratumorally injected with rAd-p53 （Gendicine） at a dose of 1×1012 vp once a week, with a total of 4-54 （mean 7.7） times. Total of 4-29 （mean 8.5） times of hyperthermia was given to the patients. Among the 44 patients, 30 patients were concurrently added with radiotherapy of a total dose 30-76 Gy/15-38 f/3-8 w （mean 58 Gy）. Results： Before and after intratumoral injection of rAd-p53, the VEGF IHC positive cell scores were 2.80 and 1.50, respectively （P=0.031）. The treatment of rAd-p53 combined with hyperthermia plus or not plus radiotherapy in advanced cancer achieved CR rate of 13.60% （6/44）, and PR rate of 29.6% （13/44）, and thus the effective rate was 43.2%. In addition to 6 patients with CR, 19 patients （19/38, 50.0%） had low density area （LDA） of more than 50% area on CT image within tumor indicating tumor tissue necrosis. Conclusions： Our data indicate that rAd-p53 inhibits VEGF expression and angiogenesis, and promotes tumor necrosis and shrinkage induced by hyperthermia plus or not plus radiotherapy in advanced cancer.

Combination of Recombinant Adenovirus-p53 with Radiochemotherapy in Unresectable Pancreatic Carcinoma

Objective：To assess the safety and efficacy of the combination of recombinant adenovirus-p53 （rAd-p53） with radiochemotherapy for treating unresectable pancreatic carcinoma.Methods：The eligible patients received concurrent rAd-p53 intratumoral injection and radiochemotherapy.Intratumoral injection of rAd-p53 was guided by B ultrasound.Radiochemotherapy consisted of intensity-modulated radiotherapy （IMRT） at two dose levels and intravenous gemcitabine （Gem）.For radiotherapy,gross target volume （GTV） and clinical target volume （CTV） were 55-60 Gy and 45-55 Gy in 25-30 fractions,respectively.Concurrent intravenous gemcitabine was administered at 350 mg/m2,weekly,for 6 weeks.The primary end points included toxicity,clinical benefit response （CBR） and disease control rate （DCR）.The secondary end points included progression-free survival （PFS） and overall survival （OS）.Results：Fifteen eligible patients were enrolled.Eight patients （53.3%） were evaluated as CBR and 12 （80%） achieved DCR.The median PFS and OS were 6.7 and 13.8 months,respectively.One-year PFS and OS were 40.0% and 51.1%,respectively.There were 8 （53.3%） patients reported grade 3 toxicities including neutropenia （6 patients,40%）,fever （1 patient,6.7%） and fatigue （1 patient,6.7%）.There was no grade 4 toxicity reported.Conclusion：Combination of rAd-p53 in unresectable pancreatic carcinoma showed encouraging efficacious benefit and was well tolerated.Long-term follow-up is needed to confirm the improvement of PFS and OS.

Recombinant adenovirus-p53(Gendicine) sensitizes a pancreatic carcinoma cell line to radiation

Objective： In this study, we examine the effects of recombinant adenovirus-p53 （rAd-p53） on the pancreatic carcinoma cell line SW1990. Specifically, we determine if expression of rAd-p53 sensitizes these cells to radiation. Methods： Following transfection of SW1990 cells with rAd-p53, we measured expression of P53, P21 and Bax by immunocytochemistry. Both transfected and control cell lines were irradiated with a range of doses, and the survival fractions （SF） were calculated. Dose survival cttrves were constructed and modeled for comparison. Results： Transfection of SW1990 cells with rAd-p53 resulted in increased expression of P53, P21 and Bax in a time-dependent manner. At 96 h after transfection, 89.92% of cells expressed P53, 56.8% expressed P21, and 76.50% expressed Bax. The SF following radiation was lower in the rAd-p53 transfected cells compared to the control cells, suggesting that rAd-p53 sensitizes SW1990 cells to radiation （Do for the experimental and control groups was 2.199 and 2.462, respectively）. Conclusions： Use of the adenoviral vector is an effective means of transfecting SW1990 cells with wild-type P53, and this sensitizes the cell line to irradiation. This work suggests that combining rAd-p53 with radiation therapy in pancreatic cancer may be therapeutically beneficial.

重组P_(53)基因在HepG-2中的表达及作用

为进一步探索正常Ｐ５３ 对肿瘤细胞增殖的抑制作用，本文用磷酸钙ＤＮＡ共沉淀法，将本室构建的ＰＸＴ１Ｐ５３ 真核表达细胞转移至ＨｅｐＧ２ 肝癌细胞系内，经斑点杂交技术和间接免疫荧光技术证实，外源性Ｐ５３ 基因已在ＨｅｐＧ２ 细胞中稳定表达，导入的Ｐ５３基因亦能抑制ＨｅｐＧ２ 肝癌细胞系增殖并诱导其凋亡。实验结果提示正常Ｐ５３ 基因可成为治疗不同肿瘤的重要靶分子之一。

p53基因治疗对鼻咽癌患者CD34标记的微血管密度和血小板计数的影响

目的观察放化疗联合重组人p53腺病毒注射液(rAd-p53)治疗鼻咽癌后对原发灶中CD34标记的微血管密度(CD34-MVD)及血小板(PLT)计数的影响,探讨其与预后的关系。方法 63例中晚期鼻咽癌患者随机分为两组,基因组32例给予rAd-p53瘤内注射+同步放化疗;常规组31例仅给予同步放化疗。采用免疫组化二步法检测两组患者癌组织中CD34-MVD水平,并检测PLT。结果治疗后基因组鼻咽癌原发灶CD34-MVD明显低于治疗前(P<0.05),而常规组治疗前后CD34-MVD比较差异无统计学意义(P>0.05);治疗后两组PLT均显著下降(P均<0.05),并且基因组下降更明显(P<0.05)。随访3年,基因组和常规组局部复发、远处转移率比较差异无统计学意义(P>0.05);但CD34-MVD表达增加组远处转移率(38.5%)明显高于表达下降组(13.5%)(P<0.05),3年总生存率、无瘤生存率低于表达下降组(P<0.05);PLT增加组与PLT下降组的局部复发率、远处转移率、3年总生存率、无瘤生存率差异均无统计学意义(P均>0.05)。结论放化疗联合基因治疗中晚期鼻咽癌,可使CD34-MVD、PLT计数明显下降。CD34-MVD过度表达可作为评估远处转移和预后不良的参考指标。

Au^(q+)(q=53-47)激光等离子体的辐射复合速率系数

辐射复合过程在超组态碰撞辐射(SCROLL)模型中真实模拟非局域热动力学平衡(non-LTE)高Z材料Au激光等离子体M带谱5f-3d跃迁中各种复杂离子的电离态特性是一个主要过程.基于准相对论多组态Hartree-Fock理论和扭曲波近似,采用组态平均的方法,从头计算了金M带类铁金离子-类锗金离子的辐射复合速率系数,计算过程中包含了大量的单激发和双激发态,结果表明高Z元素由于自电离能级的广泛分布和复杂的级联效应,致使高Z元素的辐射复合系数不同于低Z元素的,其计算结果可用来模拟Au的激光等离子体M带5f-3d跃迁的平均电离度和电荷态分布及能级布居数.

重组P_(53)真核表达载体的构建

为进一步探索Ｐ５３基因与机体发育、肿瘤发生的关系及其与细胞周期中其它调控因子的相互作用，我们采用粘性末端连接法构建了重组野生型Ｐ５３－ＰＸＴ１真核表达载体，并成功地转化Ｃａｃｌ２处理的ＲＲ１细胞，经多种方法鉴定表明其连接率为６９％，转化率为３９×１０３／μｇＤＮＡ。该重组载体的构建无疑将为肿瘤。

Synergistic anticancer effect of exogenous wild-type p53 gene combined with 5-FU in human colon cancer resistant to 5-FU in vivo

AIM To investigate the anticancer effect of a recombinant adenovirus-mediated p53(r Ad-p53) combined with 5-fluorouracil(5-FU) in human colon cancer resistant to 5-FU in vivo and the mechanism of r Ad-p53 in reversal of 5-FU resistance.METHODS nude mice bearing human colon cancer SW480/5-FU(5-FU resistant) were randomly assigned to four groups(n = 25 each): control group, 5-FU group, r Ad-p53 group, and r Ad-p53 + 5-FU group. At 24 h, 48 h, 72 h, 120 h and 168 h after treatment, 5 mice were randomly selected from each group and sacrificed using an overdose of anesthetics. The tumors were removed and the protein expressions of p53, protein kinase C(PKC), permeability-glycoprotein(P-gp) and multidrug resistance-associated protein 1(MRP1)(Western blot) and apoptosis(TUNEL) were determined.RESULTS The area ratios of tumor cell apoptosis were larger in the r Ad/p53 + 5-FU group than that in the control, 5-FU and r Ad/p53 groups(P < 0.05), and were larger in the r Ad/p53 group than that of the control group(P < 0.05) and the 5-FU group at more than 48 h(P < 0.05). The p53 expression was higher in the r Ad/p53 and the r Ad/p53 + 5-FU groups than that of the control and 5-FU groups(P < 0.05), and were higher in the r Ad/p53 + 5-FU group than that of the r Ad/p53 group(P < 0.05). Overexpression of PKC, P-gp and MRP1 was observed in the 5-FU and control groups. In the r Ad/p53 + 5-FU group, the expression of P-gp and MRP1 was lower that of the control and 5-FU groups(P < 0.05), and the expression of PKC was lower than that of the control, 5-FU and r Ad/p53 groups at more than 48 h(P < 0.05). In the r Ad/p53 group, the expression of P-gp and MRP1 was lower that of the control and 5-FU groups at more than 48 h(P < 0.05), and the expression of PKC was lower than that of the control and 5-FU groups at more than 120 h(P < 0.05).CONCLUSION5-FU combined with r Ad-p53 has a synergistic anticancer effect in SW480/5-FU(5-FU resistance), which contributes to reversal of 5-FU resistance.

Twenty years of Gendicine?rAd-p53 cancer gene therapy:The first-in-class human cancer gene therapy in the era of personalized oncology

Genetic mutations in TP53 contribute to human malignancies through various means.To date,there have been a variety of therapeutic strategies targeting p53,including gene therapy to restore normal p53 function,mutant p53 rescue,inhibiting the MDM2-p53 interaction,p53-based vaccines,and a number of other approaches.This review focuses on the functions of TP53 and discusses the aberrant roles of mutant p53 in various types of cancer.Recombinant human p53 adenovirus,trademarked as Gendicine,which is the first anti-tumor gene therapy drug,has made tremendous progress in cancer gene therapy.We herein discuss the biological mechanisms by which Gendicine exerts its effects and describe the clinical re-sponses reported in clinical trials.Notably,the clinical studies suggest that the combination of Gendicine with chemotherapy and/or radiotherapy may produce more pronounced efficacy in slowing tumor growth and progression than gene therapy/chemotherapy alone.Finally,we summarize the methods of administration of recombinant human p53 adenovirus for different cancer types to provide a reference for future clinical trials.

酵母双杂交技术筛选宫颈癌HeLa细胞cDNA文库中FAM92A1-289关联蛋白

目的应用酵母双杂交技术从宫颈癌He La细胞c DNA文库中筛选FAM92A1-289关联蛋白。方法构建酵母双杂交p GBKT7-FAM92A1-289诱饵载体,转化至酵母AH109感受态细胞中。利用Clontech GAL4酵母双杂交系统筛选He La细胞c DNA文库中与FAM92A1-289相互作用的蛋白质,用营养缺陷型培养基和X-a-Gal双重筛选实验进行筛选,对筛选结果进行生物信息学分析,对克隆重复率较高的蛋白进行回转验证,将β-半乳糖苷酶活性阳性的克隆进行测序并分析。结果成功构建酵母双杂交p GBKT7-FAM92A1-289诱饵载体,可在酵母细胞中正常表达FAM92A1-289,且对酵母细胞无毒性,不存在自激活现象。筛选出在SD/-Ade/-His/-Leu/-Trp四缺培养基及含X-a-Gal的SD/-Ade/-His/-Leu/-Trp四缺培养基上均能生长且β-半乳糖苷酶活性阳性的克隆9个。经生物信息学分析发现4种蛋白重复率较高,即增殖细胞核抗原(PCNA)、半乳糖凝集素1(Galectin-1)、内质网高尔基体中间室标记物53(ERGIC-53)、重组人BCL2相关永生基因1(BAG1),并均与FAM92A1-289存在相互作用。结论利用酵母双杂交技术在Hela细胞c DNA文库中成功筛选出与FAM92A1-289相互作用的蛋白,为进一步研究FAM92A1-289的功能提供了新线索。

重组旋毛虫53000抗原蛋白通过激活M2型巨噬细胞减轻脂多糖对肝脏的损害

目的 研究重组旋毛虫53 000抗原蛋白（rTsP53）是否通过激活M2巨噬细胞减轻脂多糖（LPS）所致肝损害.方法 60只雄性BALB/c小鼠,按随机数字表法分为LPS组、LPS＋磷酸盐缓冲液（PBS）组及rTsP53干预组,每组20只.3组动物禁食8h后腹腔注射15 μg/kg LPS;LPS＋ PBS组在注射LPS后1h注射等量PBS;rTsP53干预组在注射LPS后1h注射5 mg/kg rTsP53蛋白.干预后48 h处死小鼠,提取腹腔巨噬细胞,用流式细胞仪检测巨噬细胞标志物CCR7（M1型）及CD206（M2型）表达变化;取肝脏组织制作切片,苏木素-伊红（HE）染色观察病理改变,双染色免疫荧光检测F4/80（＋）HLA-DR（＋）及F4/80（＋）CD163（＋）表达情况;取外周血,检测血清天冬氨酸转氨酶（AST）及丙氨酸转氨酶（ALT）水平.结果 与LPS组、LPS＋ PBS组比较,rTsP53干预组小鼠生存率明显提高（90％比25％、30％,均P＜0.01）;肝脏病理损害减轻,组织结构明显改善;血清ALT、AST水平明显降低[ALT （U/L）：97.7±8.5比181.7±19.5、173.7±17.2,AST（U/L）：142.7±12.1比235.7±9.9、213.7±6.7,均P＜0.05];腹腔巨噬细胞FITC-CD206（＋）比例明显升高[（17.75±0.30）％比（1.38±0.13）％、（1.36±0.05）％,均P＜0.05],腹腔巨噬细胞PE-CCR7（＋）比例明显下降[（6.89±0.11）％比（15.30±0.64）％、（14.96±0.93）％,均P＜ 0.05];肝组织切片内F4/80（＋）CD163（＋）细胞表达荧光强度明显增强（0.36±0.01比0.29±0.02、0.31±0.01,均P＜0.05）,而F4/80（＋）HLA-DR（＋）荧光强度则无明显差异（0.30±0.01比0.30±0.02、0.31±0.01,均P＞0.05）.LPS组与LPS＋ PBS组各指标比较差异均无统计学意义（均P＞0.05）.结论 rTsP53蛋白可以通过促进体内M2型巨噬细胞活化,减轻LPS所致肝组织损害,提高动物生存率.

重组旋毛虫53000抗原蛋白联合亚胺培南对多细菌感染脓毒症小鼠的保护作用

目的观察重组旋毛虫53000抗原蛋白（rTsP53）联合亚胺培南（IMP）对脓毒症小鼠的保护作用，初步探讨其可能机制。方法按随机数字表法将雄性BALB／e小鼠分为5组，采用盲肠结扎穿孔术（CLP）构建多细菌感染小鼠脓毒症模型（CLP组），假手术（Sham）组仅开腹、关腹，不进行结扎。CLP＋IMP组、CLP＋rTsP53组、cLP＋IMP＋rTsP53组分别于术后6h起腹腔注射IMP20mg／kg＋0．1mL白蛋白、rTsP53蛋白6mg／kg＋0．1mL生理盐水（Ns）、IMP20mg／kg＋rTsP53蛋白6mg／kg；Sham组、CLP组则给予0．1mL白蛋白＋0．1mLNS；12h重复1次，至实验结束。各组取20只小鼠观察72h存活情况；并于术后0、6、12、24、36、48、72h各取3只小鼠血标本，采用酶联免疫吸附试验（ELISA）检测血清细胞因子水平，全血培养进行活菌菌落计数。24h处死小鼠取小肠组织，透射电镜下观察小肠黏膜上皮细胞超微结构。结果①cLP＋IMP＋rTsP53组小鼠存活率明显高于CLP组、CLP＋IMP组、CLP＋rTsP53组（85％比20％、55％、25％，均P〈0．05o②Sham组各时间点全血均未培养出细菌；各实验组术后6h活菌计数均显著升高，CLP组呈先升后降趋势，于24h达峰值（×10^6cfu／L：12．74±2．33）；CLP＋rTsP53组12h起显著高于CLP组，于36h达峰值（×10^6cfu／L：22．13±4．28）后逐渐下降；CLP＋IMP组、CLP＋IMP＋rTsP53组于6h达峰值（×10^6cfu／L：5．72±0．50、5．49±0．59）后呈逐渐下降趋势，12h起即显著低于CLP组。③各实验组术后6h起血清细胞因子水平均明显高于Sham组。CLP组肿瘤坏死因子-α（TNF-α）呈先升后降趋势，于36h达峰值（ng／L：1422：67±72．19），CLP＋IMP组、CLP＋rTsP53组、cIJP＋IMP＋rTsP53组达峰值时间提前至12h（nglL：1376．29＋44．67、929．36±40．42、809．61±22．61oCLP组和CLP＋IMP组白细胞介素-6（IL-6）于24h达峰值（ng/L：215．39±16．05、191．63±8．99），CLP＋rTsP53组、cLP＋IMP＋rTsP53组达峰值时间提前至12h（ng／L：113．01±12．11、92．43±6．11℃ LP组IL-4、IL-10均逐渐升高至72h达峰值（ng／L：366．25±24．25、923．14±30．36），CLP＋IMP组IL-4、IL-10分别于12h、24h达峰值（ng／L：281．47±16．33、555．67±13．57）后逐渐下降，CLP＋rTsP53组、cLP＋IMP＋rTsP53组IL-4、IL—10均逐渐升高至72h达峰值[IL-4（ng／L）分别为453．14±18．53、410．43±15．75，IL-10（ng/L）分别为1185．61±16．74、1006．77±36．91]。cLP＋IMP＋rTsP53组12h起各炎性因子水平均显著低于CLP＋IMP组、CLP＋rTsP53组。④术后24h，cLP＋IMP＋rTsP53组小肠黏膜上皮微绒毛、细胞连接、线粒体等超微结构损伤较CLP组、CLP＋IMP组、cLP＋rTsP53组明显减轻。结论rTsP53蛋白联合IMP干预可使多细菌感染脓毒症小鼠促炎因子水平降低、抑炎因子升高、存活率提高；而rTsP53蛋白单独干预未能显现出保护作用，且血细菌计数升高。

重组旋毛虫53000蛋白在M0型巨噬细胞极化中的作用及机制

目的探讨重组旋毛虫53000蛋白在M0型巨噬细胞极化中的作用及机制。方法获取骨髓来源的M0型巨噬细胞为研究对象,以650、700、750和800μg/mL浓度的重组旋毛虫53000蛋白干预M0型巨噬细胞,检测比较不同浓度干预24、48和72 h后的细胞因子信号传导抑制因子3(SOCS3)、M1型巨噬细胞表面特异性标记物诱导型一氧化氮合酶(iNOS)及M2型巨噬细胞标志物(FIZZ1)等mRNA表达量的变化,分析三者表达水平之间的关系。重组旋毛虫53000蛋白干预72 h后采用流式细胞仪分别检测各组巨噬细胞标志物CCR7(M1型)及CD206(M2型)比例。结果随着重组旋毛虫53000蛋白干预时间的延长,各组SOCS3表达量升高而iNOS和FIZZ1表达量降低,且同一时间点随着重组旋毛虫53000蛋白浓度升高,SOCS3表达量升高而iNOS和FIZZ1表达量降低(P<0.05)。Pearson线性相关分析结果显示,各浓度重组旋毛虫53000蛋白干预M0型巨噬细胞的SOCS3与其iNOS和FIZZ1表达量均呈负相关(P<0.05)。重组旋毛虫53000蛋白干预72 h后,流式细胞仪检测结果显示随着重组旋毛虫53000蛋白浓度的升高,FITCCD206(+)巨噬细胞比例亦不断升高,各浓度间比较差异具有统计学意义(P<0.05)。结论重组旋毛虫53000蛋白可能通过调控SOCS3表达诱导M0型巨噬细胞向M2型巨噬细胞极化且极化趋势具有一定的剂量依赖性。

Regulation of DNA double-strand break repair pathway choice:a new focus on 53BP1

Maintenance of cellular homeostasis and genome integrity is a critical responsibility of DNA double-strand break(DSB)signaling.P53-binding protein 1(53BP1)plays a critical role in coordinating the DSB repair pathway choice and promotes the non-homologous end-joining(NHEJ)-mediated DSB repair pathway that rejoins DSB ends.New insights have been gained into a basic molecular mechanism that is involved in 53BP1 recruitment to the DNA lesion and how 53BP1 then recruits the DNA break-responsive effectors that promote NHEJ-mediated DSB repair while inhibiting homologous recombination(HR)signaling.This review focuses on the up-and downstream pathways of 53BP1 and how 53BP1 promotes NHEJ-mediated DSB repair,which in turn promotes the sensitivity of poly(ADP-ribose)polymerase inhibitor(PARPi)in BRCA1-deficient cancers and consequently provides an avenue for improving cancer therapy strategies.

Mitsugumin 53 protects the kidney from severe burn injury in mice

Mitsugumin 53 (MG53), a newly identified muscle-specific protein, is an essential component of the cell membrane repair machinery in skeletal and cardiac muscle. However, the role of MG53 after burns in other tissues remains unclear. This study aims to investigate the possible roles of MG53 in the protection of the kidney after severe burn injury, and an animal scalding model of 30% of total body surface area (TBSA) was used. Recombinant human MG53 (rhMG53) or bovine serum albumin (BSA) was injected intravenously via the tail vein. Data showed that the mortality in the MG53-treated group was lower than that in control group. Administration of rhMG53 may alleviate histological alterations in renal tubular epithelial cells after burn injury. Renal tubular injury scores and the average optical density score of kidney injury molecule-1 (KIM-1) immunohistochemical staining in the MG53-treated group were significantly lower than those in control group (P < 0.001). Exogenous rhMG53 was found to be located in renal tubular epithelial cells. Numerous polymerase I and transcript release factor (PTRF) were expressed in the mouse kidney after severe scalding. In conclusion, our data indicate that MG53 protein protects the kidney by involving local PTRF after severe burn injury.

Functional analysis of the acetylation of human p53 in DNA damage responses

As a critical tumor suppressor, p53 is inactivated in human cancer cells by somatic gene mutation or disruption of pathways required for its activation. Therefore, it is critical to elucidate the mechanism underlying p53 activation after genotoxic and cellular stresses. Accumulating evidence has indicated the importance of posttranslational modifications such as acetylation in regulating p53 stability and activity. However, the physiological roles of the eight identified acetylation events in regulating p53 responses remain to be fully understood. By employing homologous recombination, we introduced various combinations of missense mutations （lysine to arginine） into eight acetylation sites of the endogenous p53 gene in human embryonic stem cells （hESCs）. By determining the p53 responses to DNA damage in the p53 knock-in mutant hESCs and their derivatives, we demonstrate physiological importance of the acetylation events within the core domain （Kt20 and K164） and at the C-terminus （K370/372/373/381/382/ 386） in regulating human p53 responses to DNA damage.

DCAF1 (VprBP): emerging physiological roles for a unique dual-service E3 ubiquitin ligase substrate receptor

Cullin-RING ligases(CRLs)comprise a large group of modular eukaryotic E3 ubiquitin ligases.Within this family,the CRL4 ligase(consisting of the Cullin4[CUL4]scaffold protein,the Rbxl RING finger domain protein,the DNA damage-binding protein 1[DDB1],and one of many DDBl-associated substrate receptor proteins)has been intensively studied in recent years due to its involvement in regulating various cellular processes,its role in cancer development and progression,and its subversion by viral accessory proteins.Initially discovered as a target for hijacking by the human immunodeficiency virus accessory protein r,the normal targets and function of the CRL4 substrate receptor protein DDBl-Cul4-associated factor 1(DCAF1;also known as VprBP)had remained elusive,but newer studies have begun to shed light on these questions.Here,we review recent progress in understanding the diverse physiological roles of this DCAF1 in supporting various general and cell type-specific cellular processes in its context with the CRL4 E3 ligase,as well as another HECT-type E3 ligase with which DCAF1 also associates,called EDD/UBR5.We also discuss emerging questions and areas of future study to uncover the dynamic roles of DCAF1 in normal physiology.