Search

Long non-coding RNAs (lncRNAs) are associated with the occurrence, development and prognoses of non-small cell lung cancer (NSCLC). In the present study, we investigated the functional mechanisms of the lncRNA XIST in two human NSCLC cell lines, A549 and NCI-H1299. In all the 5 NSCLC cell lines (NL9980, NCI-H1299, NCI-H460, SPC-A-1 and A549) tested, the expression levels of XIST were significantly elevated, as compared with those in normal human bronchial epithelial cell line BEAS-2B. In A549 and NCI-H1299 cells, knockdown of XIST by siRNA significantly inhibited the cell proliferation, migration and invasion, and promoted cell apoptosis. Furthermore, XIST knockdown elevated the expression of E-cadherin, and suppressed the expression of Bcl-2. Moreover, knockdown of XIST significantly suppressed the tumor growth in NSCLC A549 xenograft mouse model. Bioinformatic analysis and luciferase reporter assays revealed that XIST was negatively regulated by miR-449a. We further identified reciprocal repression between XIST and miR-449a, which eventually influenced the expression of Bcl-2: XIST functioned as a miRNA sponge of miR-449a, which was a negative regulator of Bcl-2. These data show that expression of the lncRNA XIST is associated with an increased growth rate and metastatic potential in NSCLC A549 and NCI-H1299 cells partially through miR-449a, and suggest that XIST may be a potential prognostic factor and therapeutic target for patients with NSCLC.

Gefitinib is the first targeted drug approved for non-small cell lung cancer (NSCLC) treatment. Clinical trails showed that patients with certain clinical and histologic characteristics (such as women, patients of East Asian descent, no history of smoking, and adenocarcinoma) had higher rates of response and overall survival. Despite excellent clinical response to gefitinib in certain NSCLC patients, nearly all patients who respond initially to gefitinib later develop drug resistance. Isothiocyanates have been shown to possess antitumor activity, inhibiting several types of cancer cells growth. However, there are limited studies on their effects on chemoresistance of cancer cells. In this report, we found that benzyl isothiocyanate (BITC) inhibited gefitinib-resistant human NSCLC cells growth by inducing apoptosis in a dose-dependent manner, and activated caspase-3. There were no effects of BITC on epidermal growth factor receptor and multidrug resistant proteins expression. BITC caused cell cycle arrest at G2/M phase, reactive oxygen species generation, and glutathione depletion. Akt activity and NFκB transcriptional activation were suppressed; mitogen-activated protein kinase and activator protein 1 (AP-1) were activated. Our results demonstrated that BITC overcame gefitinib resistance in lung cancer cells. The further understanding of the anti-resistance mechanism of BITC would contribute to establish it as a potent lead compound for the synthesis of novel anticancer drugs.

Purpose: This study aims to explore the association of CpG island methylator phenotype (CIMP) involving tumor suppressor genes on short arm of chromosome 3 (3p) with increased risk of non-small cell lung cancer (NSCLC)., Methods and Materials: In this study, four NSCLC cell lines were cultured, and peripheral blood mononuclear cell (PBMC) specimens from 80 patients with NSCLC and 80 matched controls were collected for 3p-involved CIMP (3pCIMP) analysis. 3pCIMP was referred to as having at least three synchronously methylated genes of 3p per sample. Methylation-specific polymerase chain reaction was performed to examine the methylation status of each gene. DNA demethylation of NSCLC cell lines was achieved through the treatment with 5-aza-deoxycytidine. Logistic regression was used to assess odds ratios and 95% confidence intervals, which were adjusted for gender, age, and smoking status., Results: Demethylation experiment showed that 3pCIMP status could play an important role in NSCLC cell proliferation. A total of 97.5% of PBMC specimens from NSCLC patients presented promoter methylation of any one of six genes (hOGG1, RAR-B, SEMA3B, RASSF1A, BLU, or FHIT) on 3p. Interestingly, 3pCIMP+ was found in 43.8% of NSCLC PBMC specimens and only in 6.3% of normal PBMC samples. The data suggest that 3pCIMP status is significantly associated with NSCLC and normal PBMC samples (p 0.001). More importantly, the results show that 3pCIMP positive carriers have a 12.8-fold increased risk of NSCLC (adjusted odds ratio, 12.8; 95% confidence interval, 4.38 -37.4, p 0.001) in Chinese population., Conclusions: This is the first evidence of an association between PBMC 3pCIMP and risk for NSCLC.

CpG island methylator phenotype (CIMP) involving methylation abnormalities of tumor suppressor gene (TSG) on short arm of chromosome 3 (chromosome 3p) has not been so far epigenetically elucidated in non-small cell lung cancer (NSCLC). Using methylation-specific PCR (MSP) method, we examined methylation profiles for eight TSGs harbored in chromosome 3p in 60 NSCLC tissues and 60 paired normal tissues as well as 11 normal blood samples. CIMP positive is referred to having four or more than four synchronously methylated genes per sample. Consequently, 59 of 60 (98.3%) NSCLC presented promoter methylation of at least one gene while only one malignant tumor showed no methylation of any of eight genes. The frequency of promoter methylation for eight genes explored ranged from 12% for hMLH1 to 67% for RASSF1A given that of VHL (none) was not considered. Interestingly, CIMP+ was found in 56.7% (34/60) of NSCLC, and in 6.7% (4/60) of paired normal tissues and 0% (0/11) of normal blood samples, respectively; CIMP- was present in 43.3% (26/60) of NSCLC, 93.3% (56/60) of paired normal tissues, and 100% (11/11) of normal blood samples, respectively. The data suggest that CIMP status was significantly associated with NSCLC, paired normal tissues and normal blood samples (P<0.001). In addition, there appeared to be a significant association between CIMP status and survival prognosis of NSCLC (P=0.0166). In the present study, for the first time, we shed light on the presence of chromosome 3p-specific CIMP, which might play an important role in tumorigenesis of NSCLC.

Objective: To investigate the role of first pass dynamic 16-slice spiral computed tomography in the evaluation of tumor angiogenesis in patients with non-small cell lung cancer (NSCLC) and to assess its importance in predicting pathologic characteristics., Methods: The first pass dynamic 16-slice spiral computed tomography was performed in 33 patients with NSCLC. Their peak heights (PH) were measured with dynamic evaluation software. Their angiogenesis were labelled by anti-CD34 monoclonal antibody. The first pass peak heights (PH) in 33 patients with NSCLC were compared with their microvessel densities (MVD) and their relationships were assessed by linear regression analysis., Results: Among the 33 patients with NSCLCs, the mean first pass PH and MVD of N1-2 were significantly higher than those at stage No (P < 0.01). The first pass PH of 33 NSCLC was correlated positively with MVDs. To differentiate stage N0 from stage N1-2 with 12 HU cutoff value of the first pass PH, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 88.0%, 75.0%, 84.8%, 91.7% and 66.7%, respectively., Conclusion: The first pass dynamic contrast enhanced CT may be a predictor of tumor angiogenesis in patients with NSCLC and its pathologic characteristics, and may be helpful to improve the accuracy of lymph node staging with conventional CT.

Background & Objective: Recently, studies showed nm23, E-cadherin, and Catenins play important roles in cellular signal transduction, which enhance complexity of their functions in tumor metastasis and can partly explain the diversity of the results from different studies. This study was to investigate correlations of expressions of nm23, E-cadherin, and beta-Catenin in non-small cell lung cancer (NSCLC) to metastasis and prognosis, and their interrelations., Methods: Expressions of nm23, E-cadherin, and beta-Catenin in 112 specimens of NSCLC and 30 specimens of benign pulmonary lesion were detected by SP immunohistochemistry., Results: The expressions of nm23, E-cadherin and beta-Catenin were significantly weaker in NSCLC tissues than in adjacent non-cancerous tissues, and benign pulmonary tissues (53.0% vs. 64.8%, and 76.9%, P < 0.01; 53.1% vs. 79.7%, and 83.5%, P < 0.01; and 47.2% vs. 80.6%, and 85.6%, P < 0.01), significantly weaker in NSCLC tissues with lymph node metastasis than in those without metastasis (48.0% vs. 65.0%, P < 0.01; 47.3% vs. 60.5%, P < 0.01; and 41.8% vs. 60.3%, P < 0.01), and significantly weaker in NSCLC tissues of stage III-IV than in those of stage I-II (44.8% vs. 67.2%, P < 0.01; 46.6% vs. 64.3%, P < 0.01; 38.1% vs. 63.1%, P < 0.01). The 5-year survival rates of patients with weak expressions of nm23, E-cadherin, and beta-Catenin were significantly lower than those of patients with strong expressions (3.6% vs. 39.3%, P < 0.01; 6.8% vs. 35.8%, P < 0.01; and 3.8% vs. 37.3%, P < 0.01)., Conclusions: Down-regulations of nm23, E-cadherin, and beta-catenin closely relate to metastasis of NSCLC. Detection of nm23, E-cadherin, and beta-Catenin might be helpful to predict prognosis of NSCLC patients.

Objective: To analyze the effects and side effects of paclitaxel liposome formula on breast cancer and non-small cell lung cancer, compared with traditional taxol., Methods: 129 patients from multicenters were prospectively randomized into a test group, given paclitaxel liposome at 135 mg/m(2) each session, and a control group, given traditional taxol at 135 mg/m(2) each session. Both groups received these regimens combined with ADM or DDP for two cycles (3 weeks per cycle)., Results: Of 129 cases, 128 were eligible for the analysis of side effects and 126 for the overall response rate. The complete remission rate, partial remission rate and overall response rate were 1.6%, 33.3%, 34.9% in the test group and 6.3%, 22.2%, 28.6% in the control group. There was no significant difference between the two groups. Though there was no significant difference in hematological toxicity between the two groups, the toxicity from the mixed solvent of polyethoxylated castor oil and ethanol was significantly lower in the test group than that in the control group., Conclusion: Paclitaxel liposome combined with ADM or DDP in the treatment of advanced breast cancer and non-small-cell lung cancer, being similarly effective as taxol, can significantly lower the incidence of serious hypersensitive reactions.

Objective: To evaluate the specificity, sensitivity and their clinical significance of detecting CK19 mRNA expression by nested RT-PCR for molecular diagnosis of micrometastasis in the peripheral blood and bone marrow of patients with non-small cell lung cancer., Methods: CK19 mRNA expression was detected by nested RT-PCR in peripheral blood and bone marrow samples from 59 lung cancer patients, with samples of 11 benign pulmonary lesion patients and 20 healthy adults as control., Results: The sensitivity of nested RT-PCR was 10(-6). The positive rates of micrometastasis were 33.89% (20/59) in peripheral blood and 22.03% (13/59) in bone marrow, with a highly positive correlation existing between the two groups (P < 0.05). The micrometastasis in peripheral blood and bone marrow was closely correlated with the pathological classification and cell differentiation (P < 0.05) and P-TNM stage (P < 0.01). No CK19 mRNA expression was found in the samples from patients with benign pulmonary lesion or healthy adult volunteers., Conclusion: The peripheral blood and bone marrow from patients with non-small cell lung cancer possesses micrometastasis that can not be detected by common methods. Nested RT-PCR technique shows favorable specificity and sensitivity in detecting the condition with definite clinical prospects.