Effects of Glucocorticoid on IL-13-induced Muc5ac Expression in Airways of Mice

Summary: To study the effects of glucocorticoid on the IL-13-induced Muc5ac expression in airways of mice, and investigate its role in mucus secretion of airways, 24 pathogen-free BALB/c mice were randomly divided into 3 groups. IL-13 group received an nasal instillation of 100 μg of recombinant murine IL-13 solution on days 1, 3 and 5. In dexamethasone group, dexamethasone (0.5 mg/kg) was administered intraperitoneally 24 h before and 1 h before the first instillation of IL-13 and on 4 consecutive days (day 0 to day 5, 6 consecutive days in total), while control group was not treated with IL-13 or dexamethasone. Bronchoalveolar lavage fluid (BALF) was collected and eosinophils were counted, and expression of Muc5ac mRNA and protein in lungs were detected by reverse transcription-polymerase chain reaction (RT-PCR) technology and immunohistochemical assay respectively. Our results showed that the number of mice, with positve Muc5ac protein expression, expression of Muc5ac mRNA and eosinophils in BALF after IL-13 treatment were all significantly higher than that of control group ( all P<0.01). Despite eosinophils reduced (P<0.01), the number of mice with positive Muc5ac protein expression, expression of Muc5ac mRNA after dexamethasone treatment didn't decreas significantly as compared with that of IL-13 group. It is concluded that IL-13 can up-regulate the expression of Muc5ac mRNA and protein, which may play a pivotal role in the mucus overproduction of airways. Dexamethasone can suppress IL-13-induced eosinophilic infiltration in lung but can't inhibit the mucus overproduction.

The Effects of Nimesulide Combined with Cisplatin on Lung Cancer

To study the effects of cyclooxygenase 2 selective inhibitor Nimesulide (NIM) combined with Cisplatin (DDP) on human lung cancer and the possible mechanisms, the proliferation and apoptosis of human lung cancer cell line A549 were evaluated by MTT reduction assay and flow cytometry respectively. The inhibitory effect on neoplasia in vivo was tested on nude mice subcutaneously implanted tumor. Our results showed that NIM and DDP could inhibit A549 cell proliferation in a concentration-dependent pattern; this action was enhanced when NIM (25 μmol/L) was given in combination with DDP and they worked in a synergistic or additive pattern as DDP concentration ≥1 μg/ml. NIM and DDP could induce A549 cells apoptosis and the action was augmented when used in combination (P<0.01). NIM and DDP could inhibit the growth of subcutaneously implanted tumors on nude mice (P<0.05,P<0.01) and the inhibitory rate of NIM combined with DDP was significantly higher than that of NIM or DDP group (P<0.01, P<0.01). It is concluded that combined use of NIM and DDP has significant synergistic antitumor effects on lung cancer cell line A549 and in animals in vivo. The synergy may be achieved by growth inhibition and apoptosis induction.

Expression of Angiopoietin-2 Gene in Non-small Cell Lung Cancer

To study the expression of Angiopoietin 2 (Ang 2) gene and its relationship with clinical pathological characteristics of non small cell lung cancer (NSCLC), expression of the Ang 2 mRNA was evaluated by employing reverse transcription polymerase chain reaction (RT PCR) in cancerous tissues and paired adjacent noncancerous tissues from 52 patients. The expression of Ang 2 gene was detected in a significantly greater proportion of cancerous tissues (80.8 %) than paired adjacent noncancerous tissues (53.8 %, P <0.01). No significant relationship was found between Ang 2 gene expression and patients' age, sex, histology of tumors, differentiation and TNM stages ( P >0.05). It is concluded that the up regulation of Ang 2 gene may play a role in the pathway of NSCLC carcinogenesis and Ang 2 may be used as a potential therapeutic agent for lung cancer.

Expression and Significance of Cyclooxygenase 2 Gene in Lung Cancer

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.