Inhibition of integrin ß3, a binding partner of kallistatin, leads to reduced viability, invasion and proliferation in NCI-H446 cells.

BACKGROUND: Kallistatin is a serine proteinase inhibitor and heparin-binding protein. It is considered an endogenous angiogenic inhibitor. In addition, multiple studies demonstrated that kallistatin directly inhibits cancer cell growth. However, the molecular mechanisms underlying these effects remain unclear. METHODS: Pull-down, immunoprecipitation, and immunoblotting were used for binding experiments. To elucidate the mechanisms, integrin ß3 knockdown (siRNA) or blockage (antibody treatment) on the cell surface of small the cell lung cancer NCI-H446 cell line was used. RESULTS: Interestingly, kallistatin was capable of binding integrin ß3 on the cell surface of NCI-H446 cells. Meanwhile, integrin ß3 knockdown or blockage resulted in loss of antitumor activities induced by kallistatin. Furthermore, kallistatin suppressed tyrosine phosphorylation of integrin ß3 and its downstream signaling pathways, including FAK/-Src, AKT and Erk/MAPK. Viability, proliferation and migration of NCI-H446 cells were inhibited by kallistatin, with Bcl-2 and Grb2 downregulation, and Bax, cleaved caspase-9 and caspase 3 upregulation. CONCLUSIONS: These findings reveal a novel role for kallistatin in preventing small cell lung cancer growth and mobility, by direct interaction with integrin ß3, leading to blockade of the related signaling pathway.

Two novel phenanthraquinones with anti-cancer activity isolated from Bletilla striata.

7-Hydroxy-2-methoxy-phenanthrene-3,4-dione and 3',7',7-trihydroxy-2,2',4'-trimethoxy-[1,8'-biphenanthrene]-3,4-dione, two novel compounds and four known compounds were isolated from Bletilla striata. The structures of the compounds were established on the basis of extensive spectroscopic analysis. The two compounds exhibited antiproliferative effects using the MTT test; these effects may be due to cell cycle arrest and inducing ROS generation.

Kallistatin, a new and reliable biomarker for the diagnosis of liver cirrhosis.

Kallistatin, which protects organs and cells against inflammation, fibrosis and oxidative stress, is mainly synthesized and secreted in liver. However, its relationship to human liver disease remains unclear. The purpose of this study was to explore the relationship between serum kallistatin and clinical evidence of both cirrhosis and hepatocellular carcinoma (HCC), and to determine if serum kallistatin levels could be used as a diagnostic indicator of hepatic health status, especially human liver cirrhosis (LC). Our cohort consisted of 115 patients with clinically proven liver fibrosis (LF), LC, or HCC by liver biopsies, and 31 healthy controls (CON). Serum kallistatin levels were quantified by ELISA. Results of the present study demonstrated that irrespective of the underlying etiology, serum kallistatin levels were significantly lower in the LF/LC group when compared with the CON group. A decrease in serum kallistatin levels appeared to reflect the extent of cirrhosis, with the lowest levels associated with higher grades of cirrhosis. Patients with LC had a noticeable correlation between serum kallistatin levels and other serum biochemical indicators. The area under the curve (AUC) for LC, viral liver cirrhosis (VLC) and alcoholic liver cirrhosis (ALC) was 0.845, 0.757 and 0.931, respectively. In conclusion, our findings demonstrated that kallistatin, a plasma protein produced by the liver, can be a useful and reliable diagnostic indicator of hepatic health status, especially for LC.

Cytotoxic activity of the alkaloids from Broussonetia papyrifera fruits.

CONTEXT: Broussonetia papyrifera (L.) Vent. (Moraceae), a traditional Chinese medicinal herb, has been extensively applied for many years to treat various diseases. Recently, a number of compounds with biological and pharmacological activities have been extracted from the plant and used as chemotherapeutic candidates to treat a range of diseases such as cancer. OBJECTIVE: The current study was designed to isolate the alkaloid compounds from ethyl acetate extraction of Broussonetia papyrifera fruits, and to evaluate the cytotoxic activity of total alkaloids as well as individual isoquinoline alkaloids from B. papyrifera fruits. METHODS: Alkaloid compounds were isolated from the ethyl acetate extraction by silica gel column chromatography methods using CHCl3/MeOH as eluents. The compounds' structures were determined by detailed analysis of NMR, MS spectral data, and chemical methodology. Cytotoxic activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods against human A375, Hela, BEL-7402 cancer cells, and non-cancer cells. RESULTS: Two isoquinonline alkaloids were isolated and characterized as N-norchelerythrine and dihydrosanguinarine. The total alkaloids and seven individual alkaloids had higher activities on BEL-7402 and Hela cell lines with low IC50 values 6.61-47.41 and 5.97-40.17 µg/mL (<50 µg/mL). Nitidine, broussonpapyrine, and chelerythrine had strong toxic on non-cancer cells with IC50 value 18.01, 19.91, and 22.31 µg/mL, respectively. DISCUSSION: N-Norchelerythrine and dihydrosanguinarine were isolated from this plant for the first time. Our data implicated that seven isoquinoline alkaloids had cytotoxity with structure-activity relationships, which provided fundamental information for further modification of their anticancer effect.

[Studies on chemical constituents of fructus broussonetiae].

OBJECTIVE: To study the chemical constituents of Fructus Broussonetiae. METHODS: Column chromatography with silic gel was employed to isolate and purify the 80% alcohol extract of Fructus Broussonetia, and the constituents were identified by spectral methods. RESULTS: Six compounds were isolated from 80% ethanol extract. Their structures were identified as Isoterihanine (1), Chelerythrine (2), Trillin (3), Sucrose (4), beta-sitosterol (5) and Fucosterol (6). CONCLUSION: These compounds are isolated from Fructus Broussonetiae for the first time.

[Cytoxic activities of total alkaloids isolated from fructus broussonetiae in vitro].

OBJECTIVE: To observe the cytoxic activities of total alkaloids isolated from Fructus Broussonetiae on the growth inhibition in five carcinoma cell lines. METHODS: The growth inhibition was analyzed by MTT, Cell colony in the Hela, BEL-7402, A375, SMM1990, Saos-2 cell lines. RESULTS: The growth of all tumor cells were inhibited by total alkaloids isolated from Fructus Broussonetiae. CONCLUSION: The results show that total alkaloids isolated from Fructus Broussonetiae possess the role of antitumors in cell culture.

[Antioxidation activities of Fructus Broussonetia haematochrome in vitro].

OBJECTIVE: To investigate the antioxidative effects of Fructus Broussonetia Haematochrome. METHODS: NADH-PMS-NBT system was used to produce supetoxide free radical (O2-*), Fe(2+) -H2O2 system to generate hydroxyl free radical (*OH), H2O2 to stimulate oxidative hemolysis of erythrocytes of mice. MDA production in liver homogenate induced by auto-oxidation was measured by MDA kits method. RESULTS: FBH not only scavenged O2-* and *OH produced by the experimental systems directly, but also inhibited H2O2 stimulated oxidative hemolysis of erythrocytes of mice, depressed MDA production in mice liver homogenate by auto-oxidation and hepatic mitochondria expanded induced by Vit C-Fe2+ system. CONCLUSION: FBH possess an antioxidative activity.