Tauroursodeoxycholic acid attenuates endoplasmic reticulum stress and protects the liver from chronic intermittent hypoxia induced injury.

Obstructive sleep apnea that characterized by chronic intermittent hypoxia (CIH) has been reported to associate with chronic liver injury. Tauroursodeoxycholic acid (TUDCA) exerts liver-protective effects in various liver diseases. The purpose of this study was to test the hypothesis that TUDCA could protect liver against CIH injury. C57BL/6 mice were subjected to intermittent hypoxia for eight weeks and applied with TUDCA by intraperitoneal injection. The effect of TUDCA on liver histological changes, liver function, oxidative stress, inflammatory response, hepatocyte apoptosis and endoplasmic reticulum (ER) stress were investigated. The results showed that administration of TUDCA attenuated liver pathological changes, reduced serum alanine aminotransferase and aspartate aminotransferase level, suppressed reactive oxygen species activity, decreased tumor necrosis factor-α and interleukin-1ß level and inhibited hepatocyte apoptosis induced by CIH. TUDCA also inhibited CIH-induced ER stress in liver as evidenced by decreased expression of ER chaperone 78 kDa glucose-related protein, unfolded protein response transducers and ER proapoptotic proteins. Altogether, the present study described a liver-protective effect of TUDCA in CIH mice model, and this effect seems at least partly through the inhibition of ER stress.

More expression of BDNF associates with lung squamous cell carcinoma and is critical to the proliferation and invasion of lung cancer cells.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) has been reported to promote tumorigenesis and progression in several human malignancies. The purpose of this study was to explore the function of BDNF in lung squamous cell carcinoma (SCC) and adenocarcinoma (ADC). METHODS: The expression of BDNF was examined in 110 samples of lung SCC and ADC by immunohistochemistry. The protein level of BDNF was examined in 25 lung SCC or ADC samples and paired non-tumors by western blot. BDNF expression was also evaluated in human bronchial epithelial cells (HBE) and 4 lung cancer cell lines using western blot. Three BDNF mRNA variants containing exons IV, VI and IX were evaluated in HBE, two SCC (SK, LK2) and two ADC (A549, LTE) cell lines by RT-PCR. The expression and secretion of BDNF were also determined in cells using western blot and ELISA. Then the shRNA specific for BDNF was transfected into LK2 or A549 cells to further elucidate the BDNF knockdown on cell proliferation, apoptosis and invasion, which were confirmed by MTT, flow cytometry and transwell examinations. RESULTS: 71.8 % (79 out of 110) of lung SCC and ADC samples were detected positive BDNF, and high expression of BDNF was significantly correlated with histological type and T stage. Compared with non-tumorous counterparts, BDNF was apparently overexpressed in SCC and ADC tissues. In cell studies, the extensive expression and secretion of BDNF were demonstrated in lung cancer cells compared with HBE cells. Interestingly, the expressions of BDNF mRNA variant IV and VI were identical in all cells examined. However, more expression of BDNF mRNA variant IX was found in SK and LK2 cells. The apoptotic cells were increased, and the cell proliferation and invasion were both attenuated once the expression of BDNF was inhibited. When retreated by rhBDNF, BDNF knockdown cells showed less apoptotic or more proliferative and invasive. CONCLUSIONS: Our data show that BDNF probably facilitates the tumorigenesis of lung SCC and ADC. The expression of BDNF mRNA variant IX is probably more helpful to the upregulation of BDNF in SCC, and intervening the production of BDNF could be a possible strategy to lung cancer therapy.

The Hedgehog signalling pathway mediates drug response of MCF-7 mammosphere cells in breast cancer patients.

BCSCs (breast cancer stem cells) have been shown to be resistant to chemotherapy. However, the mechanisms underlying BCSC-mediated chemoresistance remain poorly understood. The Hh (Hedgehog) pathway is important in the stemness maintenance of CSCs. Nonetheless, it is unknown whether the Hh pathway is involved in BCSC-mediated chemoresistance. In the present study, we cultured breast cancer MCF-7 cells in suspension in serum-free medium to obtain BCSC-enriched MCF-7 MS (MCF-7 mammosphere) cells. We showed that MCF-7 MS cells are sensitive to salinomycin, but not paclitaxel, distinct from parent MCF-7 cells. The expression of the critical components of Hh pathway, i.e., PTCH (Patched), SMO (Smoothened), Gli1 and Gli2, was significantly up-regulated in MCF-7 MS cells; salinomycin, but not paclitaxel, treatment caused a remarkable decrease in expression of those genes in MCF-7 MS cells, but not in MCF-7 cells. Salinomycin, but not paclitaxel, increased apoptosis, decreased the migration capacity of MCF-7 MS cells, accompanied by a decreased expression of c-Myc, Bcl-2 and Snail, the target genes of the Hh pathway. The salinomycin-induced cytotoxic effect could be blocked by Shh (Sonic Hedgehog)-mediated Hh signalling activation. Inhibition of the Hh pathway by cyclopamine could sensitize MCF-7 MS cells to paclitaxel. In addition, salinomycin, but not paclitaxel, significantly reduced the tumour growth, accompanied by decreased expression of PTCH, SMO, Gli1 and Gli2 in xenograft tumours. Furthermore, the expression of SMO and Gli1 was positively correlated with the expression of CD44+ / CD24-, and the expression of SMO and Gli1 in CD44+ / CD24- tissues was associated with a significantly shorter OS (overall survival) and DFS (disease-free survival) in breast cancer patients receiving chemotherapy.

Wnt3a increases the metastatic potential of non-small cell lung cancer cells in vitro in part via its upregulation of Notch3.

Metastasis is the leading cause of death in lung cancer. Understanding the mechanisms underlying the process of metastasis is crucial for identifying novel anti-metastatic therapies. Studies indicate that the highly conserved developmental pathways, such as the Wnt and Notch signaling pathways, play important roles in the non-small cell lung cancer (NSCLC) tumorigenesis. However, the roles of both pathways in NSCLC metastasis are unclear. The present study aimed to investigate whether Wnt3a and Notch3, key components of the Wnt and Notch signaling pathways, respectively, regulate the metastatic abilities of NSCLC cells and whether there is some relationship during these regulatory events. Here, we observed that Wnt3a treatment upregulated, not only the protein expression of Notch3, but also the mRNA expression of Notch3 and its downstream genes, HES1 and HEYL. In addition, Wnt3a promoted cell invasion and anchorage-independent growth. Meanwhile, Wnt3a treatment caused epithelial­mesenchymal transition (EMT)-like morphological changes and F-actin reorganization. The western blotting data showed that Wnt3a treatment decreased the expression of E-cadherin and increased the expression of N-cadherin and vimentin. Compared with Wnt3a treatment, Notch3 shRNA transfection had opposite effects. Furthermore, Notch3 shRNA weakened the effects of Wnt3a treatment on the in vitro cell invasion and EMT. Overall, these observations suggest that Wnt3a and Notch3 may promote the metastasis of NSCLC and Notch3 upregulation is required for the Wnt3a mediated increased metastatic abilities of NSCLC.

TRAF4 participates in Wnt/ß-catenin signaling in breast cancer by upregulating ß-catenin and mediating its translocation to the nucleus.

Tumor necrosis factor receptor-associated factor 4 (TRAF4) is upregulated in various subtypes of breast cancers and cell lines; however, the precise functions of TRAF4 are poorly understood. Our objective was to investigate its relationship with ß-catenin. TRAF4 participates in several signaling pathways, such as NF-κB and JNK signaling pathways. In this study, we identified ß-catenin as a TRAF4-binding protein, have shown that TRAF4 enhanced expression of ß-catenin, and found that TRAF4 mediated the translocation of ß-catenin from the cytoplasm to the nucleus, thereby facilitating activation of the Wnt signaling pathway in breast cancer.

[Application of the Ca2+ indicator fluo-3 and fluo-4 in the process of H2O2 induced apoptosis of A549 cell].

BACKGROUND AND OBJECTIVE: Lung cancer is a common malignant tumor all over the world, and Ca(2+) is a critical regulator for apoptosis of cancer cells. The monitoring of cytoplastic Ca(2+) level in real-time will contribute to further investigate the molecular mechanisms of apoptosis mediated by Ca2+ in lung cancer cells. To evaluate the Ca(2+) indicator fluo-3 and fluo-4 in the process of H2O2 induced the apoptosis of lung adenocarcinoma A549 cells. The cytoplastic Ca(2+) concentration ([Ca(2+)]i) was determined in real-time, and the correlations between [Ca(2+)]i and cell apoptosis were investigated. The differences in fluorescence intensity and measured value were compared between the two Ca(2+) indicators. METHODS: Cells were loaded with the Ca(2+) indicator fluo-3 or fluo-4 for 1 h, and then stimulated with 50 mM H2O2. Laser scanning confocal microscope was applied to perform real-time monitoring on the variation of [Ca(2+)]i in selected cells. DAPI staining was used to observe apoptosis in H2O2 treated cells. RESULTS: Our results showed that the fluorescence intensity of fluo-4 was stronger than that of fluo-3 in the same condition of dye concentration, loading time and image acquisition parameters before or after H2O2 stimulation. The cytoplastic [Ca(2+)]i was rapidly elevated in H2O2 stimulated A549 cells. The range of [Ca(2+)]i in selected cells loaded with fluo-3 was 112.2 nM-1,069.6 nM, and that in selected cells loaded with fluo-4 was 7.6 nM-505.4 nM. Moreover, the apoptotic rate was significantly increased in H2O2 treated cells, compared with untreated ones (P<0.01). CONCLUSION: In summary, H2O2 promoted Ca(2+) release in A549 cells, and induced cell apoptosis. Ca(2+) indicator fluo-4 was probably more applicable to measure [Ca(2+)]i in cells with less content of Ca(2+).

The roles of Notch3 on the cell proliferation and apoptosis induced by CHIR99021 in NSCLC cell lines: a functional link between Wnt and Notch signaling pathways.

Wnt and Notch signaling pathways both play essential roles and interact closely in development and carcinogenesis, but their interaction in non-small-cell lung cancer (NSCLC) is poorly unknown. Here we investigated the effects of CHIR99021, a Wnt signaling agonist, or Notch3-shRNA, or the combined application of CHIR99021 and Notch3-shRNA on cell proliferation and apoptosis, as well as the expressions of Notch3, its downstream genes, cyclinA and caspase-3. Our results showed that CHIR99021 up-regulated the expression of Notch3 protein and HES1 and HEYL mRNA. CHIR99021 promoted cell proliferation and the expression of cyclinA, which were inhibited by Notch3-shRNA in these three cell lines. Moreover, Notch3-shRNA significantly attenuated the positive effects of CHIR99021 on cell proliferation and cyclinA in H460 and H157. As for apoptosis, Notch3-shRNA induced cell apoptosis and increased the expression of caspase-3, whereas CHIR99021 showed the different effects in these three cell lines. The inhibitory effect of CHIR99021 on apoptosis was significantly weakened by Notch3-shRNA only in H460. Overall, although the effects of CHIR99021 and the combined application of CHIR99021 and Notch3-shRNA on the cell proliferation and apoptosis aren't completely similar in the three cell lines, our findings still indicate that Notch3 signaling can be activated by canonical Wnt signaling and a functional link between Wnt and Notch signaling pathways exists in NSCLC, at least, which partially is associated with their regulations on the expressions of cyclinA and caspase-3.

The joint effect of hOGG1, APE1, and ADPRT polymorphisms and cooking oil fumes on the risk of lung adenocarcinoma in Chinese non-smoking females.

BACKGROUND: The human 8-oxoguanine DNA glycosylase 1 (hOGG1), apurinic/apyrimidinic endonuclease 1 (APE1), and adenosine diphosphate ribosyl transferase (ADPRT) genes play an important role in the DNA base excision repair pathway. Single nucleotide polymorphisms (SNPs) in critical genes are suspected to be associated with the risk of lung cancer. This study aimed to identify the association between the polymorphisms of hOGG1 Ser326Cys, APE1 Asp148Glu, and ADPRT Val762Ala, and the risk of lung adenocarcinoma in the non-smoking female population, and investigated the interaction between genetic polymorphisms and environmental exposure in lung adenocarcinoma. METHODS: We performed a hospital-based case-control study, including 410 lung adenocarcinoma patients and 410 cancer-free hospital control subjects who were matched for age. Each case and control was interviewed to collect information by well-trained interviewers. A total of 10 ml of venous blood was collected for genotype testing. Three polymorphisms were analyzed by the polymerase chain reaction-restriction fragment length polymorphism technique. RESULTS: We found that individuals who were homozygous for the variant hOGG1 326Cys/Cys showed a significantly increased risk of lung adenocarcinoma (OR = 1.54; 95% CI: 1.01-2.36; P = 0.045). When the combined effect of variant alleles was analyzed, we found an increased OR of 1.89 (95% CI: 1.24-2.88, P = 0.003) for lung adenocarcinoma individuals with more than one homozygous variant allele. In stratified analyses, we found that the OR for the gene-environment interaction between Ser/Cys and Cys/Cys genotypes of hOGG1 codon 326 and cooking oil fumes for the risk of lung adenocarcinoma was 1.37 (95% CI: 0.77-2.44; P = 0.279) and 2.79 (95% CI: 1.50-5.18; P = 0.001), respectively. CONCLUSIONS: The hOGG1 Ser326Cys polymorphism might be associated with the risk of lung adenocarcinoma in Chinese non-smoking females. Furthermore, there is a significant gene-environment association between cooking oil fumes and hOGG1 326 Cys/Cys genotype in lung adenocarcinoma among female non-smokers.

MiR-181a enhances drug sensitivity in mitoxantone-resistant breast cancer cells by targeting breast cancer resistance protein (BCRP/ABCG2).

Breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2) mediates multidrug resistance (MDR) in breast cancers. In this study, we aimed to investigate the role of microRNAs in regulation of BCRP expression and BCRP-mediated drug resistance in breast cancer cells. Microarray analysis was performed to determine the differential expression patterns of miRNAs that target BCRP between the MX-resistant breast cancer cell line MCF-7/MX and its parental MX-sensitive cell line MCF-7. MiR-181a was found to be the most significantly down-regulated miRNA in MCF-7/MX cells. Luciferase activity assay showed that miR-181a mimics inhibited BCRP expression by targeting the 3' untranslated region (UTR) of the BCRP mRNA. Overexpression of miR-181a down-regulated BCRP expression, and sensitized MX-resistant MCF-7/MX cells to MX. In a nude mouse xenograft model, intratumoral injection of miR-181a mimics inhibited BCRP expression, and enhanced the antitumor activity of MX. In addition, miR-181a inhibitors up-regulated BCRP expression, and rendered MX-sensitive MCF-7 cells resistant to MX. These findings suggest that miR-181a regulates BCRP expression via binding to the 3'-UTR of BCRP mRNA. MiR-181a is critical for regulation of BCRP-mediated resistance to MX. MiR-181a may be a potential target for preventing and reversing drug resistance in breast cancer.

Prognostic significance of twist and N-cadherin expression in NSCLC.

BACKGROUND: Metastasis is the most common cause of disease failure and mortality for non-small cell lung cancer after surgical resection. Twist has been recently identified as a putative oncogene and a key regulator of carcinoma metastasis. N-cadherin is associated with a more aggressive behavior of cell lines and tumors. The aim of this study was to evaluate the clinical relevance of Twist and N-cadherin expression in NSCLC, and the effects of Twist1 knockdown on lung cancer cells. METHODS: We examined the expressions of Twist and N-cadherin by immunohistochemistry in 120 cases of non-small cell lung cancer (including 68 cases with follow-up records). We also analyzed Twist1 and N-cadherin mRNA expression in 30 non-small cell lung cancer tissues using quantitative reverse transcription polymerase chain reaction. The functional roles of Twist1 in lung cancer cell lines were evaluated by small interfering RNA-mediated depletion of the protein followed by analyses of cell apoptosis and invasion. RESULTS: In lung cancer tissues, the overexpression rate of Twist was 38.3% in lung cancer tissues. Overexpression of N-cadherin was shown in 40.83% of primary tumors. Moreover, Twist1 mRNA expression levels correlated with N-cadherin mRNA levels. Furthermore, overexpression of Twist1 or N-cadherin in primary non-small cell lung cancers was associated with a shorter overall survival (P<0.01, P<0.01, respectively). Depleting Twist expression inhibited cell invasion and increased apoptosis in lung cancer cell lines. CONCLUSIONS: The overexpression of Twist and N-cadherin could be considered as useful biomarkers for predicting the prognosis of NSCLC. Twist1 could inhibit apoptosis and promote the invasion of lung cancer cells, and depletion of Twist1 in lung cancer cells led to inhibition of N-cadherin expression.

Evidence of the cross talk between Wnt and Notch signaling pathways in non-small-cell lung cancer (NSCLC): Notch3-siRNA weakens the effect of LiCl on the cell cycle of NSCLC cell lines.

BACKGROUND: Aberrant activations of Wnt and Notch signaling pathways are individually reported to be associated with the pathogenesis of non-small-cell lung cancer (NSCLC). However, the data about the cross talk between the two signaling pathways are still limited. To elucidate potential Wnt/Notch cross talk within NSCLC, we examined the impact of Notch3 activity on LiCl-induced cell cycle changes. METHODS: The lung cancer cell lines were treated with LiCl, a Wnt activator, in the absence or presence of Notch3-siRNA. Cell cycles and the expression of the regulators of cell cycle, c-MYC, p21 and Skp2 (S phase kinase-associated protein 2) were measured after treatment. RESULTS: The treatment with LiCl increased the percent of cells at S phase and G phase and the expression of c-MYC and Skp2 and decreased the expression of p21. Moreover, the expression of Notch3 and its down-stream genes, HES-1 and HEYL, was up-regulated by LiCl. Notch3-siRNA weakened the effect of LiCl on the cell cycle and resulted in attenuation of the LiCl-induced increment of c-MYC and Skp2 and the LiCl-induced decrement of p21. CONCLUSIONS: These data suggest that Notch3 activation cooperatively takes part in the LiCl-induced cell cycle changes, at least partially, associated with c-MYC, Skp2 and p21.

[The study about expression of Gli2 in vein grafts].

OBJECTIVE: To study the expression of cell cycle related factor Gli2 in autogenous vein graft and its relation with neointima formation. METHOD: Autogenous vein graft model were established in 36 male wistar rats of 8 weeks old, 140 g, by transplanting the left jugular vein to intra renal abdominal aorta with microsurgical technique. Graft veins were harvest at 14, 28 days after transplantation. The IF and W-B were used to detect the protein expression in the vein graft. At the same time Gli2- mRNA was measured by RT-PCR. RESULTS: Immunofluorescent staining showed that the Gli2+ cells was only 3.2% ± 0.4% in the normal vein, but was much more in the vein graft after surgery, was 41.3% ± 0.6%, 58.3 ± 0.6% respectively; The expression of Gli2 and PCNA were both elevated in the vein graft. There is a positive correlation between them which indicated by W-B, the relation index was 0.826; the Gli2 mRNA content was also increased in vein graft, was 8.9, 13.6 fold compared with normal vein as 1 respectively. CONCLUSION: Gli2 is upregulated in autogenous vein grafts and may correlated with the proliferation of vascular smooth muscle cells.

[Relationship between the expression of PRDM14 in non-small cell lung cancer and the clinicopathologic characteristics].

BACKGROUND AND OBJECTIVE: The positive regulatory domain proteins (PRDM) are family of transcriptional regulation related to the formation of human tumor factor and play key roles in the cell differentiation and malignant transformation. PRDM14 is a member of the PRDM family. The aim of this study is to detect the expression of PRDM14 in non-small cell lung cancer (NSCLC) tissues, and analyze its relationship with clinicopathologic characteristics of NSCLC. METHODS: PRDM14 expression was detected in 70 NSCLC specimens and 7 paracancerous tissues using the immunohistochemistry (SP method). The PRDM14 protein expression was determined in 42 NSCLC specimens and 42 paracancerous tissues by Western blot. RESULTS: Among 70 NSCLC specimens, 8 specimens showed weak expression of PRDM14 (11.43%, 8/70), 62 specimens showed moderate to strong staining of PRDM14 (88.57%, 62/70), whereas 7 paracancerous specimens showed weak staining extent. PRDM14 expression level was positively correlated with differentiation (P=0.046) and histological type (P=0.047). The positive cytoplasmic expression of PRDM14 in highly differentiated NSCLC, the low expression of PRDM14 in poorly differentiated NSCLC. The results of Western blot showed that there were significant difference between the two groups (P<0.001); expression of PRDM14 was conspicuous in NSCLC specimens but low in paracancerous tissues. PRDM14 expression level was positively correlated with differentiation (P=0.017). The positive cytoplasmic expression of PRDM14 in highly differentiated NSCLC, the low expression of PRDM14 in poorly differentiated NSCLC. CONCLUSIONS: The high expression of PRDM14 in NSCLC is associated with differentiation and histological type. The PRDM14 may play an important role in the development of NSCLC.

[The expression of sonic hedgehog in rat vein grafts].

OBJECTIVE: To study the expression of cell cycle related factor sonic hedgehog (SHH) in autogenous vein graft and its relation with neointima formation. METHODS: Autogenous vein graft model were established in 24 male Wistar rats of 8 weeks old and 140 g weight, by transplanting the left jugular vein to intra renal abdominal aorta with microsurgical technique. Graft veins were harvested at 14 d and 28 d after transplantation. The immunohistochemistry and Western blot were used to detect the SHH and PCNA expression in the vein graft. At the same time SHH mRNA was measured by quantitative real-time PCR. The opposite normal veins served as control. RESULTS: Histological staining showed that the percent of SHH+ cells was only (2.0 +/- 0.5)% in the normal vein, but was much more in the vein graft after surgery, as (39.4 +/- 0.4)% and (63.0 +/- 0.3)% respectively (P < 0.01). The expression of SHH and PCNA were both elevated in the vein graft. There was a positive correlation between them which indicated by Western blot (r = 0.808, P < 0.01). The SHH mRNA content also increased in vein graft to 9.5 and 23.8 folds of that in control. CONCLUSION: SHH is upregulated in autogenous vein grafts and may correlated with the proliferation of vascular smooth muscle cells.

TrkB is highly expressed in NSCLC and mediates BDNF-induced the activation of Pyk2 signaling and the invasion of A549 cells.

BACKGROUND: Aberrant regulation in the invasion of cancer cells is closely associated with their metastatic potentials. TrkB functions as a receptor tyrosine kinase and is considered to facilitate tumor metastasis. Pyk2 is a non-receptor tyrosine kinase and integrates signals in cell invasion. However, little is known about the expression of TrkB in NSCLC and whether Pyk2 is involved in TrkB-mediated invasion of A549 cells. METHODS: The expression of TrkB was investigated in NSCLC by immunohistochemical staining. Both HBE and A549 cells were treated with BDNF. The expression of TrkB, Pyk2 and ERK phosphorylations were assessed by western blot. Besides, A549 cells were transfected with TrkB-siRNA or Pyk2-siRNA, or treated with ERK inhibitor where indicated. Transwell assay was performed to evaluate cell invasion. RESULTS: 40 cases (66.7%) of NSCLC were found higher expression of TrkB and patients with more TrkB expression had significant metastatic lymph nodes (p = 0.028). BDNF facilitated the invasion of A549 cells and the activations of Pyk2 in Tyr402 and ERK. However, the effects of BDNF were not observed in HBE cells with lower expression of TrkB. In addition, the increased Pyk2 and ERK activities induced by BDNF were significantly inhibited by blocking TrkB expression, so was the invasion of A549 cells. Knockdown studies revealed the essential role of Pyk2 for BDNF-induced cell invasion, since the invasion of A549 cells was abolished by Pyk2-siRNA. The application of ERK inhibitor also showed the suppressed ERK phosphorylation and cell invasion. CONCLUSION: These data indicated that higher expression of TrkB in NSCLC was closely correlated with lymph node metastasis, and BDNF probably via TrkB/Pyk2/ERK promoted the invasion of A549 cells.

Association between polymorphisms in DNA repair genes and survival of non-smoking female patients with lung adenocarcinoma.

BACKGROUND: Excision repair cross-complementing group 1 (ERCC1) and group 2 (ERCC2), and X-ray repair cross-complementing group 1 (XRCC1) proteins play important roles in the repair of DNA damage and adducts. Single nucleotide polymorphisms (SNPs) of DNA repair genes are suspected to influence treatment effect and survival of cancer patients. This study aimed to investigate the relationship between polymorphisms in ERCC2, ERCC1 and XRCC1 genes and survival of non-smoking female patients with lung adenocarcinoma. METHODS: We used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to evaluate SNPs in ERCC2, ERCC1 and XRCC1 genes among 257 patients. RESULTS: The overall median survival time (MST) was 13.07 months. Increasing numbers of either ERCC1 118 or XRCC1 399 variant alleles were associated with shorter survival of non-smoking female lung adenocarcinoma patients (Log-rank P < 0.001). The adjusted hazard ratios (HRs) for individuals with CT or TT genotype at ERCC1 Asn118Asn were 1.48 and 2.67 compared with those with CC genotype. For polymorphism of XRCC1 399, the HRs were 1.28 and 2.68 for GA and AA genotype. When variant alleles across both polymorphisms were combined to analysis, the increasing number of variant alleles was associated with decreasing overall survival. Using the stepwise Cox regression analysis, we found that the polymorphisms in ERCC1 and XRCC1, tumor stage and chemotherapy or radiotherapy status independently predicted overall survival of non-smoking female patients with lung adenocarcinoma. CONCLUSIONS: Genetic polymorphisms in ERCC1 and XRCC1 genes might be prognostic factors in non-smoking female patients with lung adenocarcinoma.

[Distribution and mRNA Expression of BAMBI in Non-small-cell Lung Cancer.].

BACKGROUND: BAMBI structure is similar with that of the receptor I of TGF-beta, it broadly participates in the control of TGF-beta signaling. The aim of this study is to investigate the expression and its significance of BAMBI in non-small cell lung cancer (NSCLC) and explore the relation between BAMBI and clinical and pathological factors of NSCLC. METHODS: Sixty-three cases with NSCLC and adjacent normal tissue specimens were used for immunohistochemical assay. Thirty-one fresh lung cancer tissue specimens and surrounding normal lung tissue specimens was preserved for RT-PCR in -70 (o)C after quick-frozen in liquid nitrogen immediately. RESULTS: The level of BAMBI mRNA in cancer tissues was higher than that in the corresponding adjacent tissues (0.358+/-0.135 vs 0.249+/-0.129), with the difference being statistically significant (P =0.003). BAMBI protein expressed mainly in the membrane and the cytoplasm close to the membrane, its expression in the cancer tissue was higher than that in the adjacent tissues, the difference was significant (P <0.01). Expression of BAMBI in the cancer tissue was higher than that in the adjacent tissues, and the expression of BAMBI in adenocarcinoma of lung is higher than that in squamous carcinoma. CONCLUSIONS: The expressions of BAMBI significantly increase in NSCLC. It might be a common affair in carcinogenesis of NSCLC.

[High expression of twist is positively correlated with the differentiation of lung cancer.].

BACKGROUND: Twist has been identified as a promoting factor for epithelialmesenchymal transition (EMT), which enhances the metastatic potential of cancer. The aim of this study is to detect the expression of Twist in lung cancer tissues and cell lines, and analyze its relationship with clinicopathologic characteristics and biological behavior of lung cancer. METHODS: Twist expression was examined in 68 lung cancer specimens and 8 normal lung specimens using immunohistochemistry (S-P method). Expression levels of Twist1 and Twist2 mRNA were detected using transcription-polymerase chain reaction (RT-PCR) in HBE and 8 lung cancer cell lines. Immunofluorescence was used to detect the Twist protein expression levels and subcellular localization in lung cancer cells and HBE (human normal bronchi epithelium) cells. RESULTS: Among 68 lung cancer specimens, 9 samples showed weak expression of Twist 13.24% (9 of 68), 75.00% (51 of 68) lung cancer specimens showed moderate to strong Twist staining whereas 8 corresponding normal lung specimens showed weak staining extent. Twist expression level was positively correlated with differentiation (P =0.002) and age (P =0.012). Twist1 and Twist2 mRNA expression levels were incompatible in different histology types. The fluorescence signal of Twist protein was conspicuous in lung squamous cell carcinoma cells and adencarcinoma cells, primarily in cytoplasm, but low in HBE. CONCLUSIONS: High expression of Twist in lung cancer was associated with differentiation. Twist could be used as a valuable biomarker to evaluate the progression of lung cancer.

XRCC1 polymorphisms, cooking oil fume and lung cancer in Chinese women nonsmokers.

X-ray repair cross-complementing group 1 (XRCC1) is one of the major DNA repair proteins involved in the base excision repair (BER) and single-strand break repair (SSBR) pathway. Single nucleotide polymorphisms (SNPs) in XRCC1 may alter protein function and repair capacity, thus lead to genetic instability and carcinogenesis. To establish our understanding of possible relationships between XRCC1 polymorphisms (5'UTR -77T>C, Arg194Trp, Arg280His and Arg399Gln) and the susceptibility to lung cancer among women nonsmokers, we performed a hospital-based case-control study of 350 patients with newly diagnosed lung cancer and 350 cancer-free controls, frequency matched by age. Our results showed that exposure to cooking oil fume was associated with increased risk of lung cancer in Chinese women nonsmokers [odds ratio (OR)=2.51, 95% confidence interval (CI) [1.80-3.51], P<0.001]. Individuals with homozygous XRCC1 399Gln/Gln genotype (OR=1.75, 95% CI [1.02-3.01]) and XRCC1 -77 combined TC and CC genotype (OR=1.66, 95% CI [1.13-2.42]) showed a slightly higher risk for lung cancer overall. In the subgroup of adenocarcinoma cases, adjusted ORs were increased for individuals with homozygous XRCC1 399Gln/Gln genotype (OR=2.62, 95% CI [1.44-4.79]) and XRCC1 -77 combined TC and CC genotype (OR=1.85, 95% CI [1.19-2.86]). Haplotype analysis showed that T-Trp-Arg-Gln haplotypes were associated with an increased risk of lung cancer among women nonsmokers (OR=2.26, 95% CI [1.38-3.68]), however, we did not observe a statistically significant joint effect of cooking oil fume and 399Gln or -77C variant allele on lung cancer among women nonsmokers. In conclusion, XRCC1 Arg399Gln and T-77C polymorphisms may alter the risk of lung cancer in women nonsmokers in China.

[Correlation among expression of CD44, DNA content and apoptosis in female adenocarcinoma of the lung].

BACKGROUND: Cluster of differentiation 44 (CD44) is a family of transmembrane glycoproteins. As cell surface hyaluronate receptor, it has been found to be widely expressed in a variety of cells. The aim of this study is to assess the relationship among CD44 expression, DNA content, proliferation index (PI) and apoptosis in female adenocarcinoma of the lung. METHODS: The expression of CD44, DNA index (DI), PI and apoptotic rate were studied in 61 cases of female adenocarcinoma of the lung, paracancerous tissues and 45 cases of benign lesions by flow cytometry. RESULTS: The percent of DNA aneuploidy was 75.41% in adenocarcinoma. The expression of CD44, DI and PI in adenocarcinoma were significantly higher than those in paracancerous and benign controls (P < 0.01), however the apoptotic rate was obviously lower in adenocarcinoma than that in paracancerous and benign controls (P < 0.01). There was a positive correlation between CD44 and DI (P < 0.01), and a negative correlation between apoptosis and DI in adenocarcinoma (P < 0.01). CONCLUSIONS: The expression of CD44, DNA content, proliferation and apoptosis may play important regulating roles in oncogenesis, development and metastasis of female adenocarcinoma of the lung.