The tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) provokes a prolonged morphologic response and ERK activation in Tsc2-null renal tumor cells.

Loss of tumor suppressor function dramatically alters the cellular response to chemicals. The phorbol ester tumor promoter, 12-O-tetradecanoylphorbol 13-acetate (TPA), stimulates cell proliferation through rapid activation of protein kinase C (PKC), followed by gradual degradation of the kinase. TPA also activates the GTPase Rap1 in some cell types. The tumor suppressor protein Tsc2 has a proposed GTPase activating protein (GAP) function for Rap1, providing a common mechanistic target for Tsc2 and TPA. We compared the cellular response of Tsc2-null (ERC-18) and Tsc2-competent (NRK-52E) renal epithelial cells to TPA treatment. Treatment of ERC-18 cells with 100 ng/ml TPA for 24 h resulted in loss of cell-cell contact, retraction of the cell periphery and rounding. These changes were reversed 1 h after treatment in NRK-52E cells and were apparent 24 h after treatment of ERC-18 cells. Expression of Tsc2 in ERC-18 cells abrogated the prolonged morphologic response. TPA treatment rapidly increased phosphorylation of ERK, a reported downstream effector of both PKC and Rap1, in ERC-18 cells, but induced weak Rap1 activation. TPA-induced ERK phosphorylation was prolonged in ERC-18 cells compared to NRK-52E cells and expression of Tsc2 in ERC-18 cells did not inhibit prolonged ERK activation. The selective PKC inhibitor, bisindolylmaleimide VIII, however, inhibited TPA-induced changes in morphology and ERK activation. These results imply that TPA-induced changes in morphology and ERK activation are mediated primarily through PKC and not Rap1 in renal epithelial cells. These data also imply that Tsc2 expression modulates TPA-induced changes in renal epithelial cell morphology via an ERK-independent mechanism.     

白藜芦醇及其类似物的合成及抗TPA促癌作用研究

目的设计合成白藜芦醇类似物 ,并测试其抗佛波酯 (TPA)促癌作用。方法以 3,5 二羟基苯甲酸为原料经多步反应合成目标化合物 ,采用TPA致小鼠耳肿胀促癌法确定目标化合物抗TPA促癌作用。结果所有合成的目标化合物通过1H NMR确认其结构 ,大部分化合物具有明显的抗TPA促癌作用。结论白藜芦醇及其类似物具有较强抗TPA促癌作用。     

Carotid cutdown for mechanical thrombectomy in the setting of intravenous tissue plasminogen activator: A technical report

Acute ischemic stroke (AIS) is a leading cause of mortality and morbidity in the world. Patients are usually treated with endovascular methods and access is often gained trans-femoral or trans-radial. In patients with difficult anatomy, in rare cases the approach must be done trans-cervical. Our case illustrates a patient who received IVTPA prior to attempted endovascular treatment, leading to a direct carotid cutdown for mechanical thrombectomy. Our patient presented with a left M1 occlusion and had received intravenous thrombolytic at the presentation of his symptoms. Due to unfavorable anatomy and tortuous aortic arch, conventional access could not be obtained. In order to achieve reperfusion while maintaining hemostasis, a decision was made to perform an open carotid cutdown to catherize the left internal carotid artery to successfully retrieve the thrombus. This resulted in a TICI2B revascularization. This is the first reported case of direct carotid access in the setting of acute ischemic stroke with IVTPA. Open technique allowed us to maintain hemostasis while bypassing the tortuous arch and achieving reperfusion and give the patient the best chance for a functional recovery.     

血清CA153、CEA和TPA联检在术前乳腺肿瘤鉴别诊断中的价值

目的:本文探讨血清CA153、CEA和TPA联检在术前乳腺肿瘤鉴别诊断中价值,以期为乳腺癌患者即时手术提供帮助.方法:采用放射免疫分析,检测乳腺肿瘤患者和健康人群血清CA153、CEA和TPA含量.结果:在CA153、CEA和TPA血清学检测中,术前乳腺癌组与乳腺良性肿瘤和健康人群组表达水平存在明显差异.术前乳腺癌组阳性率:CA153为63.8%,CEA为22.4%,TPA为62.1%;术前乳腺癌组联检阳性率:CA153和CEA为69.8%,CA153和TPA为87.1%,三者联检为90.5%;术前乳腺癌组检测特异性:CA153为77.9%,CA153和CEA联检为77.9%,CA153和TPA联检为71.9%,三者联检为73.4%.结论:当CA153、CEA和TPA三者联检时,术前乳腺癌组诊断阳性率显著提高,阳性组特异性无明显下降,值得临床推广应用.     

人成骨细胞株HOS TE85致瘤性转化的研究

目的建立人成骨细胞株HOS TE85致瘤性转化的模型, 作为骨肉瘤癌变过程细胞分子生物学研究的模型.方法通过克隆形成率实验确定N-甲基-N′-硝基-N-亚硝基胍(N-methyl-N′-nitro-N-nitrosoguanidine, MNNG)对HOS TE85细胞转化浓度后,以MNNG作启动剂,佛波酯(12-0-Te-tradecanoyl phorbol 13-acetate, TPA)作促进剂对其进行转化,66 d后通过细胞形态、软琼脂集落形成实验和裸鼠体内致瘤实验鉴定细胞转化程度.结果经MNNG和TPA协同处理HOS TE85细胞66 d后,细胞中出现形态异常的转化灶,转化灶细胞失去接触抑制;转化细胞凝集性增强;软琼脂克隆形成率明显增加;转化细胞在裸鼠皮下成瘤,病理组织学证实为低分化骨肉瘤.结论模拟人体细胞发生恶性转化的过程,建立了HOS TE85的恶性转化模型.     

Silibinin prevents TPA-induced MMP-9 expression by down-regulation of COX-2 in human breast cancer cells

Ethnopharmacological relevance

The expression of matrix metalloproteinase-9 (MMP-9) and cyclooxygenase-2 (COX-2) are pivotal steps in breast cancer pathogenesis. In a previous study, we reported that silibinin suppresses TPA-induced MMP-9 expression through the Raf/MEK/ERK pathway.

Aims of the study

Herein we determined the co-relationship between MMP-9 and COX-2, as well as the effect of silibinin on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and COX-2 expression in the human breast cancer cells, MCF-7 and MDA-MB231.

Methods

The toxicity of silibinin was evaluated by Quick Cell Proliferation Assay Kit II. MMP-9 and COX-2 expression were analyzed by Zymography and Western blotting, respectively. Adenoviral constitutively active (CA)-MEK was used to activate MEK/ERK pathway.

Results

The expression of MMP-9 and COX-2 in response to TPA was increased, whereas TPA-induced MMP-9 and COX-2 expression was decreased by silibinin. Our results showed that TPA-induced MMP-9 expression was inhibited by celecoxib in a dose-dependent fashion, but not MMP-1-expression. Both MMP-9 and COX-2 expression were significantly increased by CA-MEK overexpression. In contrast, TPA-induced MMP-9 and COX-2 expression was decreased by UO126 (MEK1/2 inhibitor).

Conclusion

Silibinin down-regulates TPA-induced MMP-9 expression through inhibition of COX-2 expression in breast cancer cells.     

Infection of undifferentiated and differentiated promyelocytic cells (HL-60) with varicella-zoster virus

HL-60 cells can be induced to differentiate into macrophage-like cells by treatment with 12-O-tetra-decanoylphorbol-13-acetate (TPA). The relationship between virus replication and cell differentiation was investigated using HL-60 cells that had been induced to differentiate by TPA (dHL-60 cells) and undifferentiated cells (udHL-60 cells). On infection of these cells with cell-free varicella-zoster virus (VZV), virus antigens were detected in dHL-60 cells but not in udHL-60 cells, and the percentage of antigen-positive dHL-60 cells increased during incubation. Similar results were obtained by infectious center assay, and the percentage of antigen-positive cells correlated with the stage of cell differentiation. No significant difference was found in the binding of VZV to dHL-60 cells and udHL-60 cells. Furthermore, trypsin treatment after adsorption suggested that VZV penetrated into udHL-60 cells. These findings indicate that VZV may be able to replicate in mature monocytes but may be harbored in immature monocytes in vivo.     

Analgesic, anti-inflammatory and antioxidant properties of Buddleja globosa, Buddlejaceae

ETHNOPHARMACOLOGICAL RELEVANCE: Buddleja globosa, known as "matico", is employed in Chile for wound healing. AIM OF THE STUDY: To validate the traditional use of the crude drug through in vivo and in vitro evaluation of the anti-inflammatory, analgesic and antioxidant properties of its extracts. MATERIALS AND METHODS: Sequential hexane, dichloromethane, methanol and total methanol extracts were studied using bioguided fractionation. The following activities were investigated: analgesic (writhing test), oral and topic anti-inflammatory (paw- and ear-induced edema), free radical scavenging and antioxidant activities (1,1-diphenyl-2-picrylhydrazyl, DPPH, superoxide anion, lipid peroxidation and xanthine oxidase inhibition). Sodium naproxen, nimesulide, indomethacin were used as reference drugs for in vivo, quercetin and allopurinol for in vitro assays. RESULTS: A mixture of alpha- and beta-amyrins was isolated from the hexane extract that showed 41.2% of analgesic effect at 600 mg/kg, inhibited by 47.7 and 79.0% the arachidonic acid (AA) and 12-deoxyphorbol-13-decanoate (TPA)-induced inflammation at 3mg/20 microL/ear, respectively. A mixture of beta-sitosterol, stigmasterol, stigmastenol, stigmastanol and campesterol was isolated from the fraction CD4-N and beta-sitosterol-glycoside from the fraction CD5-N, reducing TPA-induced inflammation by 78.2 and 83.7% at 1mg/20 microL/ear, respectively. The fraction CD4-N at 300 mg/kg also showed analgesic activity (38.7%). The methanol extract at 600mg/kg per os showed anti-inflammatory effect (61.4%), topic anti-inflammatory (56.7% on TPA) and analgesic activity (38.5%). Verbascoside and luteolin-7-O-glucoside were the major components of the methanol extract; apigenin 7-O-glucoside was also detected. Inhibition of superoxide anion, lipoperoxidation, and DPPH bleaching effect was found in the methanol serial and global extracts. CONCLUSIONS: The present report demonstrate the analgesic and anti-inflammatory properties of Buddleja globosa and validate its use in Chilean traditional medicine.