To study the expression of cyclooxygenase 2 (COX-2) gene and its relationship with clinicopathological characteristics of lung cancer, expression of the COX-2 mRNA was evaluated by reverse transcription polymerase chain reaction (RT-PCR) in cancerous tissues and paired adjacent non-cancerous tissues from 56 patients and benign lesions from 12 patients. Our results showed that expression of COX-2 gene was detected in a significantly greater proportion of cancerous tissues (60.7%) than adjacent noncancerous tissues (10.7%, P<0.01) and benign lesions (3/12, P<0.05). Expression of COX-2 gene was higher in adenocarcinoma than in squamous carcinoma (P<0.01). There was no significant relationship between COX-2 gene expression and patients' age, sex, histological type of tumors, differentiation degree and TNM stages (P>0.05). The up-regulation of COX-2 gene in lung cancer tissues especially in adenocarcinoma suggested that COX-2 may play a role in the lung carcinogenesis and COX-2 gene may serve as a potential therapeutic target in lung cancer.
Adenocarcinoma/*enzymology ; Cyclooxygenase 2 ; Lung Neoplasms/*enzymology ; Membrane Proteins ; Prostaglandin-Endoperoxide Synthases/*biosynthesis ; Prostaglandin-Endoperoxide Synthases/genetics ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study the expression of cyclooxygenase-2 (COX-2) gene in breast cancer and its clinicopathologic characteristics.

METHODSWith beta-actin gene as reference, the COX-2 mRNA was monitored in 30 specimens of breast cancer tissue and adjacent normal breast tissue by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSThe COX-2 mRNA expression was significantly upregulated in most breast cancer tissues with range of 0.05 - 0.91 (median 0.56), which was rare in normal breast tissue with range of 0 - 0.09 (median 0). The difference of COX-2 mRNA expression between cancer and normal breast tissue was significant (rank sum test, P < 0.05). COX-2 overexpression in breast cancer was related to its lymph node metastasis (P < 0.05) but not to age, tumor size, pathologic grade or pathologic type (P > 0.05).

CONCLUSIONThe level of COX-2 mRNA expression is obviously higher in the breast cancer tissue than that in normal breast tissue. COX-2 overexpression may play a crucial role in the carcinogenesis, development of cancer and lymph node metastasis in breast cancer patients.

Adult ; Biomarkers, Tumor ; biosynthesis ; genetics ; Breast Neoplasms ; enzymology ; metabolism ; Cyclooxygenase 2 ; Female ; Gene Expression ; Humans ; Isoenzymes ; biosynthesis ; genetics ; physiology ; Membrane Proteins ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; physiology ; RNA, Messenger ; biosynthesis ; RNA, Neoplasm ; analysis ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo observe the changes in gene expression of cyclooxygenase (COX) during spontaneous recovery from stress ulcer in rats exposed to water immersion and restraint stress (WRS).

METHODSA rat model of stress ulcer was established by means of WRS, in which the changes in COX expression were detected with immunohistochemistry and reverse transcription (RT)-PCR.

RESULTSVery low levels of COX-2 expression were detected in the gastric mucosa of the control rats, and the expression increased significantly during the healing process of the stress ulcer (P<0.05). COX-1 expression in the gastric mucosa showed no significant difference between the control group and the stress ulcer groups during healing (P>0.05).

CONCLUSIONCOX-1 and COX-2 expressions in rat gastric mucosa during the recovery from stress ulcer participate in the recovery of the damaged mucosa possibly by mediating prostaglandin secretion.

Animals ; Cyclooxygenase 1 ; biosynthesis ; genetics ; Cyclooxygenase 2 ; biosynthesis ; genetics ; Gastric Mucosa ; enzymology ; Male ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Remission, Spontaneous ; Stomach Ulcer ; enzymology ; Stress, Physiological ; complications

OBJECTIVETo study the effects of sinomenine (Sin) on cell proliferation, intracellular expression of cyclooxygenase-2 (COX-2), and production of PGE2 in lipopolysaccharide-induced PC-12 cells, To explore the Sin's mechanism on nerve cell.

METHODPC-12 cells were cultured with nerve growing factors (NGF), and pretreated with Sin at various concentrations (0, 3 x 10(-6), 30 x 10(-6), 150 x 10(-6) mol x L(-1)) for 2 hours, then with or without stimulation of lipopolysaccharide (LPS). The proliferation activity of PC-12 cells was determined by 3H-TdR incorporation, and the production of PGE2 in culture supernatants of PC-12 cells was detected with competitive ELISA. Expression of COX-2 mRNA in PC-12 cells was analyzed by semi-quantitative RT-PCR, and expression of COX-2 protein was estimated by Western blot method and cellular enzyme immunoassay. Nuclear factor-kappa B (NF-kappaB) activity in whole-cell extract of PC-12 cells was also measured by an ELISA-based method.

RESULTThe data showed that Sin down-regulated the expression of COX-2 mRNA and protein, and reduced the production of PGE2 in the LPS-stimulated PC-12 cells which correlated with Sin's concentrations positively. In addition, NF-kappaB activity in LPS-stimulated cells was suppressed significantly by Sin. No inhibition of proliferation of PC-12 cells due to Sin treatment was observed.

CONCLUSIONSin mediates the down-regulation of expression of COX-2 and production of induced PGE2 in PC-12 cells by suppressing the activity of NF-kappaB.

Animals ; Cell Proliferation ; drug effects ; Cyclooxygenase 2 ; Dinoprostone ; biosynthesis ; Down-Regulation ; Lipopolysaccharides ; Morphinans ; isolation & purification ; pharmacology ; NF-kappa B ; metabolism ; PC12 Cells ; Plants, Medicinal ; chemistry ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Sinomenium ; chemistry

OBJECTIVETo observe in vitro the effect of Sinomenine, a pure alkaloid extracted from the chinese medical plant Sinomenium acutum on the activity of cyclooxygenase (COX-1 and COX-2) and the expression of COX-1 and COX-2 mRNA.

METHODMononuclear leukocytes were obtained from healthy adults. Isolated mononuclear leucocytes from human peripheral blood (PBMC) were incubated (1 x 10(6).mL-1) with or without sinomenine (or indomethacin), after incubated for 24 hours at 37 degrees C with 5% CO2; the media were assayed for the PGE2 by radioimmunoassay (RIA). LPS was used to stimulate the monocytes at a concentration of 5 micrograms.mL-1. And by RT-PCR, both COX-1 and COX-2 mRNAs were detected in Mononuclear leukocytes after incubation for different hours with drug (sinomenine or indomethacin) or not.

RESULTLPS (stimulated) induced the production of PGE2 in PBMC increasing with high expression of COX-2 mRNA; sinomenine reduced PGE2 production in LPS stimulated human monocytes more than in non-stimulated human monocytes. In comparative experiments, indomethacin, a non selective COX inhibitor, reduced the production of PGE2 equally in both states. Meanwhile, neither sinomenine(0.1-1 mmol.L-1) nor indomethacin(0.5-10 mumol.L-1) inhibited the expression of both COX-1 and COX-2 mRNAs by RT-PCR with beta-actin as reference.

CONCLUSIONIn contrast with indomethacin, Sinomenine shows a preferential inhibitory effect on COX-2 over COX-1, These results suggest that Sinomenine is a selective COX-2 inhibitor, which may be directly related to suppressing cyclooxygenase activity.

Adult ; Cyclooxygenase 1 ; Cyclooxygenase 2 ; Dinoprostone ; blood ; Humans ; Isoenzymes ; biosynthesis ; Leukocytes, Mononuclear ; enzymology ; Membrane Proteins ; Morphinans ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; metabolism ; RNA, Messenger ; biosynthesis ; Sinomenium ; chemistry

OBJECTIVETo investigate the changes of the mRNA expression and the intestinal mucosal cyclooxygenase (COXs) activity in scalded rats.

METHODSWistar rats inflicted with 30% TBSA III degree scalding were employed as the model. The changes of COX-1, COX-2 activities were determined by substrate fluorescence analysis and the mRNA expressions of COX-1 and COX-2 by RT-PCR.

RESULTSThe mRNA expressions and the activities of COX-2 in rat intestinal mucosa increased obviously after injury. But those of COX-1 exhibited lower range of change.

CONCLUSIONThe pathological mechanism of rat intestinal mucosa injury after scalding might be closely related to the COXs participation by different styles between the two enzymes.

Animals ; Burns ; enzymology ; genetics ; pathology ; Cyclooxygenase 1 ; Cyclooxygenase 2 ; Female ; Gene Expression ; Intestinal Mucosa ; enzymology ; Isoenzymes ; biosynthesis ; genetics ; metabolism ; Male ; Membrane Proteins ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; metabolism ; RNA, Messenger ; biosynthesis ; Rats ; Rats, Wistar

OBJECTIVETo study the expressions and the significance of interleukin-8 (IL-8) and cyclooxygenase-2 (COX-2) in the remnant stomach.

METHODSFifty-eight patients with gastrectomy were examined by upper gastrointestinal endoscopy. Two biopsy specimens were obtained from the stoma and the upper corpus gastric mucosa in the remnant stomach. mRNA was extracted from biopsy specimens to measure the IL-8 and COX-2 gene mRNA levels by real-time PCR method.

RESULTSIL-8 and COX-2 levels were higher in stoma than in corpus, IL-8 levels in BI anastomosis were significantly higher in stoma than in corpus (P< 0.05). In Hp-negative patients, IL-8 and COX-2 levels in stoma were significantly higher in BII anastomosis than in BI anastomosis (P < 0.05). In Hp-positive patients, IL-8 and COX-2 levels in stoma showed no significant differences between BII anastomosis and BI anastomosis. In corpus, IL-8 and COX-2 levels in Hp-positive patients were significantly higher than those in Hp-negative patients, (P < 0.05), including in BI anastomosis and in BII anastomosis.

CONCLUSIONSThe risk of the secondary stomach carcinogenesis in stoma after distal gastrectomy is higher than that in corpus; The types of anastomosis may influence the risk for the secondary stomach carcinogenesis in the remnant stomach mucosa.

Adult ; Aged ; Aged, 80 and over ; Female ; Gastric Mucosa ; metabolism ; microbiology ; Gastric Stump ; surgery ; Gastroenterostomy ; adverse effects ; methods ; Helicobacter Infections ; Helicobacter pylori ; Humans ; Interleukin-8 ; biosynthesis ; genetics ; Male ; Middle Aged ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; Stomach Neoplasms ; etiology

OBJECTIVETo observe the effect of tetramethylpyrazine (TMP) on lipopolysaccharides (LPS) induced macrophage cyclo-oxidase-2 (COX-2) gene expression and activity in RAW264.7 mice, and to further investigate the effect and mechanism of TMP on LPS induced apoptosis of cardiac myocytes in suckling mice.

METHODSRT-PCR and Western Blot (WB) were used to investigate the macrophage COX-2 gene expression, ELISA was used to measure its activity, fluorescence microscopy was used to determine the apoptosis of murine neonatal cardiac myocyte, and fluorescence spectrophotometry was used to detect the concentration of intracellular calcium ion (Ca2+).

RESULTSTMP of 10(-6) mol/L could significantly reduce the COX-2 mRNA and protein expression (P < 0.05), in 10(-5) mol/L and 10(-4) mol/L could significantly decrease the COX-2 expression (P < 0.01) stimulated by LPS, but couldn't influence the activity of COX-2 by different TMP concentration. TMP in 10(-5) mol/L could significantly lower the concentration of intracellular Ca2+ in cardiac myocyte, and antagonize the LPS induced apoptosis of cardiac myocyte in suckling mice (P < 0.05).

CONCLUSIONTMP has the pharmacological effect in inhibiting LPS induced macrophage COX-2 expression and apoptosis of cardiac myocyte in suckling mice.

Animals ; Animals, Newborn ; Apoptosis ; drug effects ; Cells, Cultured ; Cyclooxygenase 2 ; Isoenzymes ; biosynthesis ; genetics ; Lipopolysaccharides ; Macrophages ; enzymology ; Mice ; Myocytes, Cardiac ; cytology ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; Pyrazines ; pharmacology ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVESTo investigate the expression of cyclooxygenase-2 (cox-2) protein in normal squamous epithelium, squamous dysplasia and squamous cell carcinoma of the esophagus, and to elucidate the role of cox-2 in esophageal carcinogenesis.

METHODSBiopsy specimens of atypical esophageal dysplasia (n = 47) and surgical resection of squamous cell carcinoma (n = 86) were compared with normal esophageal specimens (n = 42) and the expression of cox-2 in those specimens was analyzed by immunohistochemistry and western blotting.

RESULTSA significant elevated cox-2 expression was shown in atypical esophageal squamous dysplasia and squamous cell carcinoma, as compared to that in normal esophageal squamous epithelium, with immunohistochemical stain scores of 2.67 +/- 1.77, 2.19 +/- 1.79 and 0.71 +/- 0.46, respectively. Results of western blotting analysis confirmed those obtained by immunohistochemistry. Cox-2 expression significantly correlated with proliferation activity assessed by proliferating cell nuclear antigen index in dysplastic and carcinomous lesions, respectively, and no such correlation could be found in normal esophageal mucosa. Elevated cox-2 expression was not associated with clinical-pathological features of esophageal squamous carcinoma, including age, gender, tumor size, histological grade, lymph node metastasis and clinical stage.

CONCLUSIONElevated expression of cox-2 in atypical squamous dysplasia and squamous cell carcinoma of the esophagus, which correlated with cell proliferation activity, indicated that cox-2 may be involved in the early stage of squamous carcinogenesis of the esophagus, and may be a target of prevention and treatment for esophageal squamous cell carcinoma.

Adult ; Aged ; Blotting, Western ; Cyclooxygenase 2 ; Esophageal Neoplasms ; enzymology ; pathology ; Female ; Humans ; Immunohistochemistry ; Isoenzymes ; biosynthesis ; Male ; Membrane Proteins ; Middle Aged ; Neoplasms, Squamous Cell ; enzymology ; pathology ; Prostaglandin-Endoperoxide Synthases ; biosynthesis

To investigate the effect of N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 on the formalin-induced cyclooxygenase-2 (COX-2) expression in the dorsal horn of the rat spinal cord. Forty-eight male Sprague-Dawley rats were divided into 4 groups: control, formalin, formalin+normal saline (NS) and formalin+MK-801 groups. Rats in formalin, formalin+NS and formalin+MK-801 groups were subcutaneously injected with 0.2 ml 5% formalin into the plantar surface of the right hind paw. NS or MK-801 solution (10 microl) was intrathecally injected under transient ether anesthesia 15 min prior to the formalin injection in the formalin+NS and formalin+MK-801 groups, respectively. Flinch reflex was measured within 1 h after the formalin injection and expression of COX-2 in the dorsal horn of the L(5) segment of the spinal cord was assayed 24 h after the formalin injection using immunohistochemistry. Formalin evoked a biphasic flinch reflex. MK-801 produced a limited effect on the flinch reflex of phase 1, but produced significant and dose-dependent suppression on the flinch reflex of phase 2. The number and immunostaining density, shown by grey degree which was inversely proportional to the immunostaining density, of immunoreactive soma in the superficial (mainly I-II) and deep (IV-VI) laminae of the L(5) spinal cord in formalin and formalin+NS groups increased significantly, in contrast to those in the control group (p<0.01). The number and immunostaining density of immunoreactive soma decreased significantly in formalin+MK-801 group, in comparison with the formalin+NS group (p<0.05). The degree of the decrease was proportional to the dosage of MK-801 used. In addition, there were some immunoreactive processes especially in the superficial laminae, which extended as a continuous band across the dorsal horn after the formalin injection. Change in immunostaining density of the processes after administration of MK-801 was similar to that in the immunoreactive soma. The results showed that intrathecal injection of MK-801 significantly inhibited the increase of COX-2 expression in the spinal dorsal horn induced by the formalin injection in a dose-dependent manner, suggesting that the activation of NMDA receptor is one of the mechanisms for the formalin-induced increase of COX-2 expression in the spinal dorsal horn.
Animals ; Cyclooxygenase 2 ; Dizocilpine Maleate ; pharmacology ; Formaldehyde ; Isoenzymes ; biosynthesis ; genetics ; Posterior Horn Cells ; enzymology ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; antagonists & inhibitors ; Spinal Cord ; enzymology