[Effect of Wnt signaling suppression on gefitinib in non small cell lung cancer cell lines].

OBJECTIVE: To explore the effect of Wnt signaling suppression on proliferation of non small cell lung cancer to gefitinib, and its related mechanisms. METHODS: PC9 and PC9/AB2 cells of both gefitinib sensitive and resistant were treated with different concentrations of gefitinib, and the proliferation index was measured using CCK8 kit. The members of Wnt signaling pathway were detected by Western blot. Dual luciferase reportor gene assay (TOP Flash) was used to document the transcriptional level of ß-catenin. ß-catenin siRNA was transfected into PC9/AB2 cells to suppress the Wnt signaling transcription, followed by treatment with different concentrations of gefitinib. Western blot was then used to detect the expression of EGFR and its downstream signaling after inhibit the expression of ß-catenin. RESULTS: Treating with different concentrations of gefitinib, the resistance of PC9/AB2 cells to gefitinib was significantly increased (P < 0.05). The members of Wnt signaling expressed at higher level in PC9/AB2 cells than in PC9 cells (t = 24.590, P = 0.000). TOP Flash examination showed that the endogenous transcriptional activity of Wnt signaling was higher in PC9/AB2 cell than that in PC9 cell (t = 4.983, P = 0.008). Compared with the negative control group, apoptotic rate and sensitivity to gefitinib significantly increased in interfered group (P < 0.05). The expression of p-ERK1/2 significantly decreased after Wnt signaling suppression, although other proteins showed no significant alterations. CONCLUSION: Suppressing the activity of Wnt signaling can partly reverse the celluar resistance to gefitinib in non small cell lung cancer.

[Effects of 1, 25 (OH)2D3 on bleomycin-induced pulmonary fibrosis in mice].

OBJECTIVE: To observe the effects of 1, 25(OH)2D3 on bleomycin-induced pulmonary fibrosis in mice and to explore its mechanisms. METHODS: Ninety male C57BL/6 mice, 6 to 8 weeks old, were randomly divided into 3 groups according to the table of random numbers: a control group, a model group and a treatment group(n = 30 each). Bleomycin was injected to the mice in the latter 2 groups by single intratracheal injection to duplicate the pulmonary fibrosis model, while the control group was injected with saline. From the next day, the mice in the treatment group received 1, 25 (OH) 2D3 (0.5 µg·kg(-1)·d(-1)) diluted in olive oil by gavage daily, while the other groups were treated with equivalent olive oil. Ten mice in each group were killed randomly on day 14, 21 and 28 after surgery respectively. Pulmonary alveolitis and fibrosis were evaluated by using hematoxylin-eosin and Masson stain method. The content of hydroxyproline was measured by acid hydrolysis method. The mRNA levels of collagen1α1, α-SMA, Wnt3a, Wnt4, and Wnt7a in the lung tissues were measured by real-time RT-PCR, while the protein expression of α-SMA and ß-catenin were assessed by immunohistochemistry. RESULTS: Pulmonary alveolitis at day 14, 21 and fibrosis at day14, 21, 28 in the treatment group were remarkably reduced compared to the model group (all P < 0.05). Compared with the model group, the treatment group showed decreased content of hydroxyproline, decreased mRNA levels of collagen1α1, α-SMA, Wnt3a, Wnt4 and decreased protein expression of α-SMA and ß-catenin at the 3 time points (all P < 0.05). The content of hydroxyproline and the mRNA levels of collagen1α1, α-SMA, Wnt3a, Wnt4, Wnt7a in the treatment group at 28 d were 0.67 ± 0.14, 1.66 ± 0.34, 1.37 ± 0.41, 1.43 ± 0.27, 1.29 ± 0.19, 1.18 ± 0.20, respectively, all of which were significantly lower than those in the model group (1.10 ± 0.16, 3.50 ± 0.74, 2.68 ± 0.61, 2.60 ± 0.58, 2.23 ± 0.45, 1.93 ± 0.36, respectively). Protein expression of α-SMA and ß-catenin in the treatment group were 0.44 ± 0.13 and 0.25 ± 0.05, respectively, which were also significantly lower than those of the model group(0.98 ± 0.20, 0.58 ± 0.06, respectively). CONCLUSION: 1, 25 (OH) 2D3 was shown to reduce pulmonary fibrosis induced by bleomycin in mice, and its mechanisms might be associated with Wnt signaling suppression.

[A study on the efficacy of glucocorticoid therapy for idiopathic nonspecific interstitial pneumonia].

OBJECTIVE: To investigate the efficacy of glucocorticoid therapy in idiopathic nonspecific interstitial pneumonia (INSIP). METHODS: Twenty-nine cases of INSIP confirmed by clinical- radiological-pathological (CRP) diagnosis were collected and classified into 2 groups according to the degree of fibrosis: INSIP-1 (including 9 cases of cellular type) and INSIP-2 (20 cases of mixed and fibrotic type). Thirty cases of usual interstitial pneumonia (UIP) confirmed by CRP diagnosis served as the control. Clinical and pathological features, therapeutic effects of glucocorticoids and the follow-up results were retrospectively analyzed and the survival curves were evaluated by Kaplan-Meier method. RESULTS: The mean age at onset of INSIP-1 group [(48 ± 5) years] was significantly younger than INSIP-2 group [(52 ± 11) years] and the UIP group [(57 ± 14) years]. The course of disease in INSIP-1 group [(60 ± 28) months] was longer than that in INSIP-2 group [(48 ± 33) months] and that in the UIP group [(44 ± 23) months], but the differences were not statistically significant (F = 1.22, all P > 0.05). The efficacy rate of glucocorticoid treatment in INSIP-1 group (9/9) was higher than that in INSIP-2 group (11/20) and that in the UIP group (2/30), the differences being statistically significant (all P < 0.05). The follow-up period for INSIP-1 group [(56 ± 27) months] was significantly longer than for INSIP-2 group [(23 ± 18) months] and for the UIP group [(25 ± 17) months], and the rate of significant improvement (6/9) was higher than that of the INSIP-2 group (9/20) and the UIP group (0/30), the differences being statistically significant (F = 9.224, all P < 0.05). The mortality of INSIP-1 group (0/9) was lower than that in INSIP-2 group (4/20) and the UIP group (16/30), the difference being statistically significant (exact probability value 0.000 - 0.005, P < 0.05). CONCLUSIONS: The degree of fibrosis of INSIP is closely correlated with the effect of glucocorticoid therapy and prognosis. The cellular type has a favorable reaction to glucocorticoid therapy and a better prognosis as compared to the fibrotic type.