PLPP2: Potential therapeutic target of breast cancer in PLPP family

PLPPs (Phospholipid phosphatases) are widely expressed in different human tissues, regulate cell signal transduction, and are overexpressed in cancers such as gliomas, pancreatic adenocarcinoma, lung adenocarcinoma, and so on. As a member of the PLPP family, PLPP2 (phospholipid phosphatase 2) plays a vital role in the occurrence and development of breast cancer, but its mechanism is still unclear. Our research found that PLPP2 was overexpressed in breast cancer, and the higher expression level of PLPP2 showed a worse prognosis for breast cancer patients. Further analysis showed that overexpression of PLPP2 affected the expression of CDC34 (cell-division cycle 34), LSM7 (Like-Smith 7), and SGTA (small glutamine-rich tetratricopeptide repeat-containing protein alpha) through EMT (epigenetic-mesenchymal transition) related pathways to promote the occurrence and development of breast cancer. In vitro, silencing PLPP2 significantly reduced the proliferation, invasion, and migration abilities of human breast cancer cells MDA-MB-231. ER+ is a common subtype of breast cancer. Furthermore, we found that the overexpression of PLPP2 was significantly related to the poor prognosis of ER+ breast cancer. These results indicate that PLPP2 has value as a potential therapeutic target for breast cancer, especially for ER+ breast cancer.     

施万细胞和一氧化氮合酶抑制剂对大鼠脊髓损伤后背核神经元存活及其轴突再生的影响

目的探讨施万细胞(SCs)和一氧化氮合酶(NOS)抑制剂L-NNA联合应用能否促进脊髓损伤后背核神经元存活及其轴突再生。方法20只成年大鼠分为对照组、SCs组、L-NNA组和SCs L-NNA组。在SCs L-NNA组动物T11脊髓段半横断后在损伤处植入施万细胞，术后腹腔内注射L-NNA。结果脊髓半横断后30d，对照组L1脊髓段损伤侧背核神经元数量减少，其胞体皱缩，NOS表达阳性。SCs组存活的神经元增加的同时其NOS表达增强，胞体也发生皱缩。L-NNA组和SCs L-NNA组存活的神经元也增加，但NOS表达降低，其胞体皱缩得到改善。各组中仅在SCs L-NNA组L1脊髓损伤侧背核观察到有被FG标记的神经元胞体，提示其再生轴突穿越损伤区到达头端脊髓组织。结论SCs和L-NNA都可促进脊髓半横断背核受损伤神经元的存活；两者联合应用能更好地促进受损伤背核神经元存活及其轴突再生。     

施万细胞对大鼠脊髓半横切后背核神经元存活及其表达NOS的影响

目的：探讨移植的施万细胞对大鼠脊髓半横切后背核神经元存活及其表达NOS的影响。方法：50只成年SD大鼠被分为实验组和对照组。在胸11脊髓段半横切后立即在损伤处移植入施万细胞。结果：脊髓半横切后，15d和25d对照组L1脊髓段损伤侧背核神经元的存活数均比未损伤侧的明显减少。存活的神经元胞体出现明显皱缩，有些神经元呈现NADPH－d阳性。15d和25d施万细胞组L1脊髓段损伤侧背核神经元的存活数则比同期对照组的明显增加，表达NOS的存活神经元数也随之增多。但存活的神经元胞体仍然是皱缩的。结论：移植的SCs可促进受损伤的背核神经元存活及其表达NOS，但不能阻止其胞体出现皱缩。     

CD40靶向小干扰RNA抑制大鼠异体肢体移植急性排斥反应后细胞凋亡及P53、P21表达

目的探讨CD40靶向小干扰RNA（即短发夹RNA，shRNA）对大鼠异体肢体移植急性排斥反应及细胞凋亡的影响。方法以纯系SD大鼠为供体，纯系Wistar大鼠为受体，行同种异体右后肢移植。27只大鼠肢体移植后随机分为3组：实验组．注射梭华一Sofast（15μl）-siCD40—2，pSilencer（100μg）载体复合物600μl；空载体对照组，在肢体移植后，即注射Sofast（15μl）-pSilencer4．1-CMVneo（100μg）空载体复合物600μl；生理盐水对照组，在肢体移植注射生理盐水600μl。观察移植物排斥反应征象及存活情况，并于第7天对产生免疫耐受大鼠进行混合淋巴细胞反应（MLR），同时进行组织学检查。结果与其他组相比．实验组移植物发生排斥反应的时间及存活时间均显著延长（P〈0．01）（〉13d），未见排斥反应征象，其他组均于术后近期发生排斥反应；实验组大鼠对供体的淋巴细胞呈现低反应性，移植的供体同系大鼠的肢体得以存活。实验组移植物细胞凋亡率低于其他组。结论在术后不应用免疫抑制剂的情况下，CD40靶向的shRNA干扰可以抗大鼠异体肢体移植急性排斥反应。     

TAC-101, a benzoic acid derivative, inhibits liver metastasis of human gastrointestinal cancer and prolongs the life-span

We examined the anti-tumor effect of a novel benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl) benzamide] benzoic acid) on models with liver metastasis. Oral administration of TAC-101 significantly inhibited spontaneous liver metastasis of AZ-521 (human gastric cancer ) by orthotopic implan-tation to athymic nude mice. It also inhibited both the liver metastasis of AZ-521 induced by intrasplenic injection and the secondary lung metastasis from the liver. In addition, TAC-101 inhibited the proliferation of Co-3 (human colon adenocarcinoma) that formed a single nodule in the liver of athymic nude mice by intrahepatic implantation. The growth inhibitory effect of TAC-101 on AZ-521 experimental liver metastasis was observed when treatment was started on day 7, 14, or 21 which may correspond to the progressive stage of liver metastasis in clinical settings. Multiple administration of TAC-101 (8 mg/kg/day) significantly prolonged survival time of the animals with liver met astasis by intrasplenic injection of AZ-521 (T/C = 230%) and A549 (human lung adenocarcinoma; T/C = 186%). These effects of TAC-101 were stronger than those of 5-FU, CDDP or ATRA. Furthermore, TAC-101 inhibited the binding of AP-1 to DNA on electrophoretic mobility shift assay using nuclear extract of AZ-521 cells, although ATRA did not inhibit. These findings suggested that TAC-101 may be a candidate for a new class of anti-cancer agents for liver metastasis. © Rapid Science Ltd.     

Laser-assisted zona pellucida thinning prior to routine ICSI

BACKGROUND: In MII oocytes showing difficult oolemma breakage, ICSI can cause an increase in the degeneration rate. This may be overcome by laser-assisted ICSI using a 5-10 micro m opening in the zona pellucida for injection. However, such a small opening might impair the hatching process, especially if assisted hatching is applied in addition. In order to prevent this, the present study used routine injection through an area of zona pellucida in which laser zona thinning had been applied, providing for both a reduced mechanical stress to the oocyte and assisted hatching. METHODS: This prospective study involved 100 cycles with 1016 MII oocytes. Conventional ICSI (control group) was compared with a modified laser-assisted ICSI (study group) in sibling oocytes. In the latter group oocytes were injected through an extended area of zona thinning. RESULTS: Degeneration rate was significantly lower in the study group (P < 0.004). There were no differences in fertilization, or formation and quality of blastocysts. In the study group embryo quality on day 2 was significantly better (P = 0.004) and herniation of day 5 blastocysts was increased (P = 0.005). Rates of implantation and pregnancy were not affected. However, on day 3 laser-assisted ICSI proved beneficial (P = 0.038) in terms of clinical pregnancy rate. CONCLUSIONS: The new method combines a less invasive ICSI technique with assisted hatching. Our preliminary data indicate that in addition to an improved oocyte survival, this new approach increases the hatching rate in vitro, which may explain the increase in pregnancy rate, at least in day 3 transfers.     

瘦素(leptin)对ECV-304细胞氧化应激的保护作用

目的:研究外源性瘦素(leptin)在细胞氧化应激中对细胞存活率的影响,探讨leptin在抗氧化应激方面的作用.方法:利用H2O2诱导人脐静脉内皮细胞系ECV-304细胞建立细胞氧化应激模型,设立正常对照、单纯损伤和不同浓度leptin干预组,每组7例,采用噻唑蓝(MTT)比色法检测细胞存活率;比色法测定细胞上清液中丙二醛(MDA)和乳酸脱氢酶(LDH)的含量.结果:与正常对照组相比,加入外源性leptin的三组正常ECV-304细胞存活率无显著变化,但25μg/L leptin组有升高的趋势,100μg/L leptin组有降低的趋势.与单纯损伤组相比,加入外源性leptin的三组损伤ECV-304细胞存活率显著升高(P均＜0.05).与单纯损伤组相比,加入外源性leptin的三组ECV-304细胞上清液中MDA生成量和LDH释放量显著下降(P均＜0.05).结论:leptin对ECV-304细胞的氧化应激具有剂量依赖性的保护作用.     

Differential assessment of angiogenic activity and of vascular survival ability (VSA) in breast cancer

Recent reports provide evidence that some growth factors behave as inhibitors of the apoptosis of the endothelial cells, bringing forward the concept of vascular survival as a post-angiogenesis process. At least two different vasculature development processes occur within a tumor: the angiogenic (formation of new vessels) and the vascular survival pathway, which is devoted to the preservation of the newly-formed vessels in layers that lose contact with the adjacent normal tissue. We developed a method to assess these processes in tissue samples. We noted that differences among tumors may exist not only in the tumor angiogenic activity (TAA) but also in the vascular survival ability (VSA). One third of the highly angiogenic breast cancer cases examined had a poor ability to maintain high vessel density in inner tumor areas. Both parameters are independently related to prognosis, while VSA was directly related to tumor dimensions and node involvement. Patients with high TAA and VSA had a particularly poor prognosis. It is suggested that although cancer angiogenic activity is important for the local invasion and dissemination into vessels and lymphatics, the VSA may be important for the effective formation of viable tumor foci in lymph nodes or distant organs. Recognition and quantification of the vascular survival ability in human tumors may significantly improve the prognostic value of the assessment of tumor vasculature, and may help to stratify patients for clinical trials with novel anti-angiogenic or angiotoxic drugs. Elucidation of the pathways may provide additional targets for antiangiogenic therapy. This revised version was published online in July 2006 with corrections to the Cover Date.     

中晚期重型乙型肝炎血浆置换与内科治疗生存率的比较

观察血浆置换、内科治疗对中晚期重型乙型病毒性肝炎生存率的影响,探索中晚期重型肝炎的治疗方法。方法观察在内科治疗基础上给予血浆置换患者的肝功能、并发症及疾病的转归,与同期仅予内科综合治疗的患者相比较,对相应的临床资料进行统计学分析,从而了解两种治疗方法的疗效。结果血浆置换组36例,18例好转、18例死亡,内科治疗组32例,13例好转、19例死亡,两组之间患者生存情况无统计学差异;肝功能指标(ALT、AST、SB、ALB、TC、ChE和凝血酶原时间(PT)也无统计学差异。结论与内科治疗相比较,在其基础上给予血浆置换并不能提高中晚期重型病毒性肝炎生存率;中晚期重型肝炎患者的预后决定于其肝功能衰竭的程度。     

视网膜祖细胞干细胞特性及移植入视网膜后的研究

目的：研究视网膜祖细胞的干细胞特性及移植入视网膜后的存活和迁移。方法：体外培养胎龄18d 大鼠的视网膜细胞,用 RT-PCR、细胞免疫荧光方法鉴定其增殖分化；成年 SD 大鼠腹腔注射 N-甲基-N-亚硝基脲形成视网膜感光细胞退化的动物模型,培养的视网膜祖细胞用 CM-Di(?) 标记后,移植入模型鼠的玻璃体腔。结果：视网膜祖细胞体外表达中间神经丝蛋白 nestin；表达 Flk-1、Pax6及 Notchl 的 mRNA；能掺入 BrdU；分化后表达视网膜各类细胞特异性蛋白；移植后在实验组大鼠视网膜能存活及迁移,而在对照组中仅聚集在玻璃体腔。结论：视网膜祖细胞具有干细胞特性,移植入受损伤视网膜后,能存活、整合及迁移。