18F-FDG PET/CT代谢的可重复性研究进展

18F-脱氧葡萄糖(18F-FDG)PET／CT在恶性肿瘤的早期诊断、临床分期、疗效评价、监测复发及肿瘤放疗靶区定位中具有重要价值。为了使PET/CT能够更准确地进行恶性肿瘤的疗效评价，18F-FDG PET／CT代谢的可重复性研究显得尤为重要。本文就传统临床代谢参数值标准化摄取值（SUV）、代谢活性肿瘤体积（MATV）、总病灶糖酵解（TLG）、肿瘤与肝脏比率（TLR）、肿瘤与血液比率(SUR)及近年新兴的PET图像纹理分析等方面的可重复性研究进行概述。     

4′‐Bromo‐resveratrol,a dual Sirtuin‐1 and Sirtuin‐3 inhibitor,inhibits melanoma cell growth through mitochondrial metabolic reprogramming

Sirtuin‐1 and ‐3 (SIRT1 and SIRT3) are important nicotinamide adenine dinucleotide (NAD⁺)‐dependent deacetylases known to regulate a variety of cellular functions. Studies have shown that SIRT1 and SIRT3 were overexpressed in human melanoma cells and tissues and their inhibition resulted in a significant antiproliferative response in human melanoma cells and antitumor response in a mouse xenograft model of melanoma. In this study, we determined the antiproliferative efficacy of a newly identified dual small molecule inhibitor of SIRT1 and SIRT3, 4′‐bromo‐resveratrol (4′‐BR), in human melanoma cell lines (G361, SK‐MEL‐28, and SK‐MEL‐2). Our data demonstrate that 4′‐BR treatment of melanoma cells resulted in (a) decrease in proliferation and clonogenic survival; (b) induction of apoptosis accompanied by a decrease in procaspase‐3, procaspase‐8, and increase in the cleavage of caspase‐3 and poly (ADP‐ribose) polymerase (PARP); (c) marked downregulation of proliferating cell nuclear antigen (PCNA); and (d) inhibition of melanoma cell migration. Further, 4′‐BR caused a G0/G1 phase arrest of melanoma cells that was accompanied by an increase in WAF‐1/P21 and decrease in Cyclin D1/Cyclin‐dependent kinase 6 protein levels. Furthermore, we found that 4′‐BR causes a decrease in lactate production, glucose uptake, and NAD⁺/NADH ratio. These responses were accompanied by downregulation in lactate dehydrogenase A and glucose transporter 1 in melanoma cells. Collectively, our data suggest that dual inhibition of SIRT1 and SIRT3 using 4′‐BR imparted antiproliferative effects in melanoma cells through a metabolic reprogramming and affecting the cell cycle and apoptosis signaling. Therefore, concomitant pharmacological inhibition of SIRT1 and SIRT3 needs further investigation for melanoma management.     

Colon and rectal cancer risk after bariatric surgery in a multicountry Nordic cohort study

Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980–2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28–1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92–1.39) and 1.55 (95% CI 1.04–2.31) 10–14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83–1.52; HR 1.08, 95% CI 0.79–1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker.     

利胆软坚方降脂减肥作用及其对胆汁酸代谢轮廓谱的影响

目的:基于肥胖“从胆论治”的学术观点,研究利胆软坚方对高脂饮食诱导肥胖大鼠的降脂减肥作用及其对血清胆汁酸轮廓谱的影响,探讨其作用机制。方法:42只大鼠高脂饲料喂养9周建立肥胖大鼠模型,取24只造模成功大鼠随机分为模型组、利胆软坚方高、低剂量组(30,15 g·kg^-1),每组8只,另取8只正常大鼠作为正常组,模型组和正常组给予生理盐水,给药组给予相应剂量药物,灌胃4周。测定大鼠体质量、肝脏质量、脂肪质量等肥胖指标;胆管插管术引流监测2 h内胆汁流量;全自动生化仪测定血清总胆固醇(TC),甘油三酯(TG),高密度脂蛋白胆固醇(HDL-C),低密度脂蛋白胆固醇(LDL-C)水平;超高效液相色谱-质谱联用(UPLC-MS/MS)法测定大鼠血清胆汁酸代谢轮廓谱中各胆汁酸的含量。结果:与正常组比较,模型组体质量、肝脏质量、脂肪质量均显著升高(P<0.01),血清TC,TG,LDL-C水平明显上升(P<0.05,P<0.01),2 h内胆汁总分泌量及各测试点胆汁流量均降低,初级胆汁酸占比明显下降(P<0.05),血清总胆汁酸含量显著降低(P<0.01),血清胆汁酸轮廓谱中胆酸(CA),脱氧胆酸(DCA),鹅去氧胆酸(CDCA),猪去氧胆酸(HDCA),牛磺胆酸(TCA),牛磺去氧胆酸(TDCA),牛磺鹅去氧胆酸(TCDCA),牛磺猪去氧胆酸(THDCA),甘氨去氧胆酸(GDCA)含量明显降低(P<0.05,P<0.01);与模型组比较,利胆软坚方高、低剂量组体质量、肝脏质量明显降低(P<0.05,P<0.01),利胆软坚方高剂量组血清TC,TG,LDL-C水平明显下降(P<0.05,P<0.01),低剂量组TG水平明显下降(P<0.05),高剂量组在给药后1~1.5 h胆汁流量明显增加(P<0.05),高、低剂量组初级胆汁酸占比明显升高(P<0.05),利胆软坚方高剂量组TCA,DCA,甘氨胆酸(GCA),GDCA水平明显升高(P<0.05,P<0.01),低剂量组仅TCA,TCDCA水平明显升高(P<0.05)。结论:利胆软坚方具有降脂减肥作用,其机制可能与其增加胆汁分泌量,增加初级胆汁酸合成及调节胆汁酸轮廓谱有关。     

扁塑藤素调控Notch信号通路诱导人肺癌条件重编程细胞死亡的作用机制研究

目的：应用条件性重编程细胞（conditionally reprogrammed cells，CRCs）技术建立人肺癌细胞体外长期培养体系，研究扁塑藤素对人肺癌CRCs增殖和迁移能力的影响，并探讨相关作用机制。方法：免疫组化法检测Notch 1、HES1和Cyclin D3在肿瘤组织和癌旁组织中的表达水平；使用CRCs技术分离培养非小细胞肺癌原代细胞；使用2，4，8，16 μmol·L^-1的扁塑藤素处理人肺癌CRCs，MTS法检测细胞活力，Annexin V/PI流式细胞术检测细胞凋亡，Transwell法检测细胞迁移能力，Western Blot检测细胞中Notch信号通路相关蛋白Notch 1、HES1和Cyclin D3的表达水平。结果：在非小细胞肺癌患者肿瘤组织中Notch 1、HES1和Cyclin D3的表达水平高于癌旁组织；扁塑藤素能够诱导人肺癌CRCs死亡，并在一定范围内呈现时间和浓度依赖性（P<0.05）；随着扁塑藤素作用浓度的增高，人肺癌CRCs凋亡率明显增高（P<0.05），细胞迁移能力下降（P<0.05）；扁塑藤素能够下调人肺癌CRCs中Notch 1、HES1和Cyclin D3的蛋白表达水平。结论：扁塑藤素可能通过调控Notch信号通路相关蛋白的表达水平，抑制人肺癌CRCs的增殖和迁移，并诱导其凋亡，为肺癌的治疗提供新的实验数据和理论依据。