Four New Limonoids from the Barks of Toona ciliata.

Four new limonoids, toonayunnanaes F - I (1 - 4), and six known compounds (5 - 10) were isolated from the barks of Toona ciliata. Their structures were elucidated by thoroughly analyzing of NMR and HRMS data, and single-crystal X-ray diffraction of 1. The oxetane ring moiety in 1 was rare in limonoids and other natural products.

MS diagnostic model and rapid distinguishing of bioactive limonoids in fruits of Melia toosendan using solid-phase extraction coupled with LC-MS/MS.

Introduction: Melia toosendan Sieb. et Zucc. has been used as a Chinese folk medicine for roundworm treatment since ancient times.

Ciliatasecones A-C, three rearranged limonoids from Toona ciliata var. yunnanensis.

Ciliatasecones A-C (1-3), three rearranged limonoids with a novel ring-seco model and an unprecedented cycle system, were isolated from the root bark of Toona ciliata var. yunnanensis. Ciliatasecones A-B (1-2) share a novel cyclopenta[b]furan ring C/D system through C-9/11-seco and C-11/14 ether linkage.

[Mechanism of polycomb Bmi1-targeted therapy for colorectal cancer].

Objective: To investigate the Bmi1 protein level in human colorectal cancer specimen and associated clinicopathological parameters, and to determine the influence of Bmi1 on the proliferation and apoptosis of colorectal cancer cells.

Methods: Bmi1 protein level was assessed in 85 patients with colorectal cancer and adjacent normal tissue by immunohistochemistry. SW480 cells were transfected with Bmi siRNA plasmid.

[Clinical value of screening hereditary nonpolyposis colorectal cancer in China with protocol recommended by NCCN guidelines].

Objective: To investigate the effect of the protocol recommended by NCCN-2007 on the diagnosis of hereditary nonpolyposis colorectal cancer (HNPCC) in China.

Methods: NCCN protocol consists of identifying HNPCC characteristics according to the revised Bethesda Guidelines,genetic counseling with immunohistochemistry and finally genetic testing. Four hundred and nineteen patients diagnosed as colorectal cancer from January 2002 to February 2006 were selected.

The role of cyclooxygenase-2/prostanoid pathway in visceral pain induced liver stress response in rats.

Background: Cyclooxygenase (COX) is the rate-limiting enzyme in the production of prostanoids from arachidonic acid. COX-2 is the inducible enzyme in the COX family, together with the prostanoids forms the COX-2/prostanoid pathway. Research showed that the COX-2/prostanoid pathway is activated in hepatic diseases and liver stress reaction, such as fibrogenesis, portal hypertension, carcinogenesis, and ischemic/reperfusion injury.

[Effect of tumor burden on differentiation of T lymphocytes in the peripheral blood of patients with colorectal cancer].

Objective: To analyze the effect of tumor burden on the differentiation of T1 and T2 cells and its implication in patients with colorectal cancer.

Methods: Peripheral venous blood samples were obtained from 20 patients with primary colorectal cancer before and 7 days after the operation, radical operation in 17 patients and palliative resection in 3 patients. Twenty sex and age-matched patients with benign diseases treated in the same period were used as controls.

[Correlation between Stat3 signal transduction pathway and expression of cyclooxygenase-2 in colorectal cancer cells].

Objective: To explore the expression of Stat3 signal transduction pathway and expression of cyclooxygenase-2 (COX-2) in colorectal cancer cells and their correlation with the clinicopathological parameters of colorectal cancer, and to reveal the mechanism of Stat3 signal transduction pathway regulating the expression of cCOX-2 in colorectal cancer cells.

Methods: RT-PCR was used to detect the mRNA expression of Stat3 and COX-2 and immunohistochemistry was used to detect the protein expression of Stat3 and COX-2 in 50 specimens excised during operation from 50 patients with colorectal cancer aged 58 (37-75). Human colorectal cancer cells of the HT-29 strain were cultured.

[Molecular mechanism of cyclooxygenase-2 inhibitor in inhibition of proliferation of colon cancer cells by modulating Stat5 signal transduction pathway].

Objective: To investigate the role of NS398, a selective cyclooxygenase (COX)-2 inhibitor, in proliferation and apoptosis of colorectal cancer, and to reveal the mechanism of inhibiting colon cancer by NS-398 Independent of COX-2.

Methods: Human colon cancer cells of the line SW480 were cultured and then divided into 2 groups: experimental group and control group. NS398 of the concentrations of 12.

[Change in apoptosis and its mechanism in intestinal epithelial cells under oxidative stress].

Objective: To investigate change in apoptosis level and its mechanism of intestinal epithelial cells under oxidative stress.

Methods: HT-29 cells were cultured in vitro, which were treated with hydrogen peroxide (H2O2), to simulate the intestinal epithelial cells injured by reactive oxidative species. The cells viability was observed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

[The effect of transfecting Stat3beta cDNA on human breast cancer].

Objective: To study the effect of transfecting Stat3beta cDNA on human breast cancer.

Methods: Human breast cancer cells of the line SK-BR-3 were cultured and divided into 3 groups: Stat3beta transfection group (to be transfected with plasmid pIRES-Stat3beta containing Stat3beta by transient transfection technique), lipofectin reagent transfection group pIRES-EGFP transfection group, and control group. The positively transfected cells were isolated by fluorescence-activated cell sorter.

[Expression and significance of estrogen receptor isoforms in the development of human breast carcinoma].

Objective: To investigate the estrogen receptors (ER)alpha and ERbeta expression and their relationship with clinicopathological parameters in human breast carcinoma.

Methods: Samples were obtained from 30 breast carcinoma, reverse transcriptase polymerase chain reaction was used to measure the expression of ERalpha and ERbeta mRNA.

Results: ERalpha mRNA level was up-regulated in breast carcinoma tissue compared with adjacent normal tissue (t = 7.

Constitutive activation of Stat3 signaling pathway in human colorectal carcinoma.

Aim: Signal transducers and activators of transcription (STATs) are a family of transcription factors activated in response to cytokines and growth factors. Constitutive activation of Stat3 has been observed in a growing number of tumor-derived cell lines, as well as tumor specimens from human cancers. The purpose of this study was to investigate the expression of p-Stat3, activated form of Stat3, and its downstream mediators including cyclin D1 and Bcl-x(L) in colorectal carcinoma (CRC), and to explore the possible mechanism of Stat3 signaling pathway in the tumorigenesis of colorectal carcinoma.

[Effects of selective cyclooxygenase-2 inhibitor NS-398 on 5-fluorouracil chemotherapy and progression of colon cells: an experimental study].

Objective: To investigate the effects of selective cyclooxygenase-2 (COX-2) inhibitor NS-398 on 5-fluorouracil (5-Fu) chemotherapy and on the progression of colon cells.

Methods: Colon cancer cells of HT-29 and SW480 lines were cultured. Selective COX-2 inhibitor NS-398, 5-Fu, or NS-398 combining with 5-Fu were added into the cultures to be co-cultured for 24, 48, and 72 hours respectively.

[Relationship of Stat3 and its target gene products with malignancy in human colorectal carcinoma].

Background & Objective: Signal transducers and activators of transcription 3 (Stat3) pathway can be activated by cytokines and growth factors, and activation of Stat3 is involved in modulating cell proliferation, differentiation, and apoptosis. Stat3 has been classified as an oncogene because Stat3 can mediate malignant transformation of cultured cells. This study was conducted to investigate the expression of Stat3 and its target gene products including Cyclin D1 and Bcl-x(L) in human colorectal carcinoma (CRC) tissues and cells, and to explore the mechanisms in tumorigenesis of CRC.