Why subclinical involvement is prescribed the same high dose as gross tumor volume: A study on high-dose clinical target volume in intensity-modulated radiotherapy plan of nasopharyngeal carcinoma.

BACKGROUND: Most nasopharyngeal carcinoma (NPC) protocols define primary gross tumor volume (GTVnx) plus a range from 2 to 5 mm as the high-dose clinical target volume (hd-CTV). However, in China, hd-CTV is defined as GTVnx plus 0 mm. METHODS: A total of 40 patients with newly diagnosed nonmetastatic NPC (T1-T4 ten cases each) treated with IMRT were consecutively enrolled. Real and virtual treatment plans were designed according to the definitions of hd-CTV recommended by China and Radiation Therapy Oncology Group (RTOG), respectively. RESULTS: The hd-CTV in China was significantly smaller than that of RTOG. Exposure doses to 5 mm subclinical involvement and OARs as well as NTCP in the China treatment plan were significantly lower than those of RTOG. CONCLUSION: It could be recommended to divide the hd-CTV into GTV and subclinical target volume and to prescribe different doses for the GTV and subclinical involvement in the IMRT plan of NPC.

Survival outcomes, hematologic complications and growth impairment after sequential chemoradiotherapy in intracranial NGGCTs: a retrospective study.

PURPOSE: This study aimed to evaluate the clinical features, prognostic factors, and survival outcomes for patients with intracranial nongerminomatous germ cell tumors (NGGCTs), with a particular focus on treatment toxicity for long-term survivors. METHODS: Intracranial NGGCTs treated with platinum-based chemotherapy and craniospinal irradiation (CSI) in our institution were retrospectively analyzed. Hematological complications following sequential chemoradiotherapy as well as height and weight in childhood survivors were evaluated. Plasma growth hormone (GH) concentrations prior to and after radiotherapy were obtained for the comparisons. RESULTS: A total of 111 intracranial NGGCTs were included. The 3­year overall survival (OS) and event-free survival (EFS) rates were 83.5% ± 3.9% and 71.0% ± 4.8%, respectively. A combined treatment modality consisting of ≥ 4 cycles of platinum-based chemotherapy and CSI was associated with an improved OS (P = 0.003) and EFS (P < 0.001). Thrombocytopenia of any grade occurred in 35.4% (34/96) of patients, and the threshold age for an increased risk of thrombocytopenia was 14 years (area under the curve AUC = 0.752, P < 0.0001) as derived from receiver operating characteristic (ROC) analysis. Growth impediment was found in 8 of 56 (14%) patients. The age for receiving radiotherapy was found to inversely correlate with height development, revealing a cut-off age of 11.5 years for risking growth impairment (AUC = 0.806, P = 0.004). Consistently, a significant decline in plasma growth hormone after radiotherapy was observed in patients ≤ 11.5 years (P < 0.01) but not patients > 11.5 years. (P > 0.05). CONCLUSION: Our study suggested that a combined treatment modality with at least four cycles of chemotherapy and CSI was safe and effective for patients with intracranial NGGCTs. Radiotherapy should be used with caution for patients < 11.5 years due to growth impairment.

Prognostic Value of E2F Transcription Factor Expression in Pancreatic Adenocarcinoma.

BACKGROUND Pancreatic adenocarcinoma (PAAD) is one of the deadliest types of cancer. In the early stages, patients often have atypical symptoms, making diagnosis difficult. The prognosis of diagnosed patients is very poor and treating PAAD is challenging. Therefore, determining reliable risk factors related to PAAD development is critical for improving patient prognosis. E2F family transcription factors (TFs) are essential regulators of DNA synthesis and cell cycle progression in eukaryotic cells, and they have been identified as prognostic biomarkers associated with multiple cancer types. However, further research is necessary to establish the prognostic relevance of these TFs in PAAD patients. MATERIAL AND METHODS We assessed PAAD patient transcriptional and outcome data using the TIMER, ONCOMINE, STRING, GEPIA, cBioPortal, Kaplan-Meier Plotter, GSCALite, and starBase databases. RESULTS PAAD tumor tissues exhibited increased expression of E2F1/3/5/7/8 relative to that in normal tissues, while the expression of E2F2/3/6/8 was associated with a more advanced tumor stage. Survival analyses indicated that PAAD patients expressing higher levels of E2F1/2/3/7/8 exhibited shorter overall survival (OS) and disease-free survival (DFS) than patients expressing lower levels of these TFs. In addition, E2F4 and E2F6 overexpression was associated with poorer DFS and OS, respectively. We also found that the expression of E2Fs was significantly correlated with immune infiltrates, including CD8+ T cells, CD4+ T cells, B cells, dendritic cells, neutrophils, and macrophages. CONCLUSIONS Our study may provide new insights into the optimal choice of immunotherapy and promising novel targets for therapeutic intervention in PAAD patients.

Absolute quantification of 2-hydroxyglutarate on tissue by matrix-assisted laser desorption/ionization mass spectrometry imaging for rapid and precise identification of isocitrate dehydrogenase mutations in human glioma.

Isocitrate dehydrogenase (IDH) gene mutations are important predictive molecular markers to guide surgical strategy in brain cancer therapy. Herein, we presented a method using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) for absolute quantification of 2-hydroxyglutarate (2-HG) on tissues to identify IDH mutations and evaluate tumor residue. This analytical method was tested among 34 glioma patients and validated with gold standard clinical technologies. The cut-off value of 2-HG was set as 0.81 pmol/µg to identify IDH mutant (IDHmt) gliomas with 100% specificity and sensitivity. In addition, 2-HG levels and tumor cell density (TCD) showed positive correlation in IDHmt gliomas by this spatial method. This MALDI MSI-based absolute quantification method has great potentiality for incorporating into surgical workflow in the future.

Individualized Nomogram for Predicting Survival in Patients with Brain Metastases After Stereotactic Radiosurgery Utilizing Driver Gene Mutations and Volumetric Surrogates.

It is well-known that genomic mutational analysis plays a significant role in patients with NSCLC for personalized treatment. Given the increasing use of stereotactic radiosurgery (SRS) for brain metastases (BM), there is an emerging need for more precise assessment of survival outcomes after SRS. Patients with BM and treated by SRS were eligible in this study. The primary endpoint was overall survival (OS). Cox regression models were used to identify independent prognostic factors. A survival predictive nomogram was developed and evaluated by Concordance-index (C-index), area under the curve (AUC), and calibration curve. From January 2016 to December 2019, a total of 356 BM patients were eligible. The median OS was 17.7 months [95% confidence interval (CI) 15.5-19.9] and the actual OS at 1- and 2-years measured 63.2 and 37.6%, respectively. A nomogram for OS was developed by incorporating four independent prognostic factors: Karnofsky Performance Score, cumulative tumor volume, gene mutation status, and serum lactate dehydrogenase. The nomogram was validated in a separate cohort and demonstrated good calibration and good discriminative ability (C-index = 0.780, AUC = 0.784). The prognostic accuracy of the nomogram (0.792) was considerably enhanced when compared with classical prognostic indices, including the Graded Prognostic Assessment (0.708), recursive partitioning analysis (0.587), and the SRS (0.536). Kaplan-Meier curves showed significant differences in OS among the stratified low-, median- and high-risk groups (P < 0.001). In conclusion, we developed and validated an individualized prognostic nomogram by integrating physiological, volumetric, clinical chemistry, and molecular biological surrogates. Although this nomogram should be validated by independent external study, it has a potential to facilitate more precise risk-stratifications to guide personalized treatment for BM.

YBX1 mediates autophagy by targeting p110ß and decreasing the sensitivity to cisplatin in NSCLC.

Y-box binding protein 1 (YBX1) is involved in the development of multiple types of tumors. However, the relationship between YBX1 and autophagy in non-small cell lung cancer (NSCLC) remains unclear. In this study, we analyzed the expression and clinical significance of YBX1 and markers of autophagy (LC3I/II) in NSCLC and examined their roles in regulating sensitivity to cisplatin in NSCLC. The retrospective analysis of patients with NSCLC indicated that YBX1 was positively correlated with autophagy. Increased levels of YBX1 or autophagy also observed in NSCLC cells compared with those in 16HBE cells. Compared to the controls, the knockdown of YBX1 expression suppressed autophagy, increased drug sensitivity and promoted apoptosis in response to cisplatin in NSCLC cells by targeting the p110ß promoter and inhibiting p110ß/Vps34/beclin1 signaling pathways. We also demonstrated in an in vivo study that the overexpressed YBX1 effectively increased NSCLC growth and progression and decreased the sensitivity to cisplatin by inducing autophagy in a xenograft tumor model, and these effects were concomitant with the increasing of p110ß and beclin1 expression. Collectively, these results show that YBX1 plays an essential role in autophagy in NSCLC.

α1,6-Fucosyltransferase (FUT8) regulates the cancer-promoting capacity of cancer-associated fibroblasts (CAFs) by modifying EGFR core fucosylation (CF) in non-small cell lung cancer (NSCLC).

Cancer-associated fibroblasts (CAFs) are the main cancer-promoting component in the tumor microenvironment (TME) of non-small cell lung cancer (NSCLC). α1,6-Fucosyltransferase (FUT8), the key enzyme catalyzing core α1,6-fucosylation (CF), plays a promoting role in multiple malignancies. In the current study, we investigated the function of FUT8 in CAFs and elucidated the mechanism through which FUT8 regulates the cancer-promoting capacity of CAFs in NSCLC. A bioinformatics analysis was performed to reveal the relationship between FUT8 and CAFs. Resected specimens from NSCLC patients were analyzed to assess the expression of FUT8 in CAFs. Primary CAFs and normal lung fibroblasts (NLFs) were extracted from NSCLC patient specimens and were co-cultured with NSCLC cell lines in a novel 3D-printed non-contact co-culture device. An In vivo CAF/NSCLC co-injection tumorigenesis assay was performed using nude mice to study the function of FUT8/CF in TME formation. The current study revealed that FUT8-mediated CF in CAFs plays a positive role in the cancer-promoting capacity of these cells. FUT8 overexpression was observed in CAFs isolated from some lung adenocarcinoma cases. Further investigation showed that FUT8/CF in CAFs promoted the formation of an invasive and malignant TME in vivo and in vitro, and the resulting NSCLC cells exhibited faster proliferation and increased invasiveness. EGFR signaling exerts a catalytic effect on the cancer-promoting capacity of CAFs and is regulated by the CF modification of the EGFR protein.

MicroRNA-30e inhibits proliferation and invasion of non-small cell lung cancer via targeting SOX9.

Previous studies have reported that microRNA-30e (miR-30e) is dysregulated in multiple human cancers. However, the expression, functions and molecular mechanism of miR-30e in NSCLC remain unknown. In this study, we found that miR-30e was expressed at a low level in NSCLC tissues and cell lines. In NSCLC cell lines, enforced expression of miR-30e could inhibit cell proliferation and invasion in vitro. In addition, miR-30e negatively regulated SOX9 expression through directly binding to the 3'UTR of SOX9, and an inverse correlation was found between miR-30e and SOX9 mRNA expression in NSCLC tissues. Moreover, knockdown of SOX9 led to decreased proliferation and invasion of NSCLC cells. Taken together, miR-30e acts as a tumor suppressor in NSCLC, and inhibits cell proliferation and invasion possibly by directly targeting SOX9. These findings might provide novel therapeutic targets for NSCLC.

BPTF cooperates with p50 NF-κB to promote COX-2 expression and tumor cell growth in lung cancer.

Cyclooxygenase-2 (COX-2) is overexpressed in most human cancers, but its precise regulatory mechanism in cancer cells remains unclear. The aims of this study are to discover and identify the new regulatory factors which bind to the COX-2 promoter and regulate COX-2 expression and cancer cell growth, and to elucidate the mechanisms of action of these factors in lung cancer. In this study, the COX-2 promoter-binding protein BPTF (bromodomain PHD finger transcription factor) was detected, identified and verified by biotin-streptavidin-agarose pulldown, mass spectrum analysis and chromatin immunoprecipitation (ChIP) in lung cancer cells, respectively. The expressions of COX-2 and BPTF in lung cancer cell lines, mouse tumor tissues and human clinical samples were detected by RT-PCR, Western blot and immunohistochemistry assays. The interaction of BPTF with NF-kB was analyzed by immunoprecipitation and confocal immunofluorescence assays. We discovered and identified BPTF as a new COX-2 promoter-binding protein in human lung cancer cells. Knockdown of BPTF inhibited COX-2 promoter activity and COX-2 expression in lung cancer cells in vitro and in vivo. We also found that BPTF functioned as a transcriptional regulator through its interaction with the p50 subunit of NF-kB. Knockdown of BPTF abrogated the binding of p50 to the COX-2 promoter, while the inhibition of p50 activity abolished the decreased trend of COX-2 expression and lung cancer cell proliferation caused by BPTF silencing. Moreover, we showed that the expressions of BPTF and COX-2 in tumor tissues of lung cancer patients were positively correlated, and high co-expression of BPTF and COX-2 predicted poor prognosis in lung cancer patients. Collectively, our results indicated that BPTF cooperated with p50 NF-κB to regulate COX-2 expression and lung cancer growth, suggesting that the BPTF/p50/COX-2 axis could be a potential therapeutic target for lung cancer.

Functional role of RBM10 in lung adenocarcinoma proliferation.

Lung cancer is one of the most common causes of morbidity and mortality among malignant tumors worldwide. The poor prognosis of patients with lung adenocarcinomas is primarily due to its strong ability to invade and metastasize. Recent research has indicated that RNA­binding protein 10 (RBM10) is mutated in lung adenocarcinoma, and is closely associated with tumor proliferation and apoptosis; however, the precise role of RBM10 in lung adenocarcinoma remains unclear. Our preliminary experiments (unpublished data) revealed that RBM10 expression was upregulated in lung adenocarcinoma cell lines and tissues. In this study, we first detected the protein expression level of RBM10 in lung adenocarcinoma cells and tissues, and we then examined the effects of RBM10 overexpression and downregulation (via small interfering RNA) on the proliferation and apoptosis of stable lung adenocarcinoma cells, along with its possible mechanisms of action. We also used clinical samples of lung adenocarcinomas to verify our results. We found that RBM10 protein was overexpressed in lung adenocarcinoma cells and tissues, and it reduced p53 expression (as detected by immunofluorescence assay and western blot analysis) in A549 cells and inhibited apoptosis (as shown by flow cytometric assay). RBM10 also promoted cell growth and proliferation in vitro and increased cell migration in a cell wound scratch assay. Furthermore, we found that RBM10 activated key proliferative signaling pathways [such as the epidermal growth factor receptor (EGFR), mitogen­activated protein kinase (MAPK) and phosphoinositide 3­kinase (PI3K)­AKT pathways] and inhibited apoptotic pathways. In addition, we demonstrated that a high expression of RBM10 protein in patient tissue samples was associated with a shorter overall survival time and a poor prognosis. On the whole, the findings of this study indicate that RBM10 may function as an oncogene in lung cancer, and may thus prove to be a novel therapeutic target for the prophylaxis and treatment of lung adenocarcinomas.

p38 MAPK is Crucial for Wnt1- and LiCl-Induced Epithelial Mesenchymal Transition.

Idiopathic pulmonary fibrosis (IPF) is characterized by myofibroblast foci in lung parenchyma. Myofibroblasts are thought to originate from epithelial-to-mesenchymal transition (EMT). Wnt1 and lithium chloride (LiCl) induce EMT in alveolar epithelial cells (AECs), but the mechanisms are unclear. AECs were treated with Wnt1 and LiCl, respectively; morphological change and molecular changes of EMT, including E-cadherin, fibronectin, and vimentin, were observed. SB203580 was administrated to test the role of p38 МАРК signaling in EMT. Then AECs were treated with siRNAs targeting p38 МАРК to further test the effects of p38 МАРК, and the role was further confirmed by re-expression of p38 МАРК. At last P-catenin siRNA was used to test the role of ß-catenin in the EMT process and relationship of ß-catenin and p38 МАРК was concluded. Exposure of AECs to Wnt1 and LiCl resulted in upregulation of vimentin and fibronectin with subsequent downregulation of E-cadherin. Wnt1 and LiCl stimulated the p38 МАРК signaling pathways. Perturbing the p38 МАРК pathway either by SB203580 or through p38 МАРК siRNA blocked EMT and inhibited fibronetin synthesis, which were reversed by transfection of p38 МАРК expression plasmid. ß-catenin siRNA attenuated the EMT process and decreased p38 МАРК phosphorylation, indicating that ß-catenin is involved in the EMTrelated changes through regulation of p38 МАРК phosphorylation. These findings suggest that p38 МАРК participates in the pathogenesis of EMT through Wnt pathway and that p38 МАРК may be a novel target for IPF therapy.

Novel Mechanism of the Pericyte-Myofibroblast Transition in Renal Interstitial Fibrosis: Core Fucosylation Regulation.

Pericytes have been identified as a major source of myofibroblasts in renal interstitial fibrosis (RIF). The overactivation of several signaling pathways, mainly the TGF-ß and PDGF pathways, initiates the pericyte-myofibroblast transition during RIF. Key receptors in these two pathways have been shown to be modified by fucosyltransferase 8 (FUT8), the enzyme that catalyzes core fucosylation. This study postulated that core fucosylation might play an important role in regulating the pericyte transition in RIF. The data showed that core fucosylation increased with the extent of RIF in patients with IgA nephropathy (IgAN). Similarly, core fucosylation of pericytes increased in both a unilateral ureteral occlusion (UUO) mouse model and an in vitro model of pericyte transition. Inhibition of core fucosylation by adenoviral-mediated FUT8 shRNA in vivo and FUT8 siRNA in vitro significantly reduced pericyte transition and RIF. In addition, the activation of both the TGF-ß/Smad and PDGF/ERK pathways was blocked by core fucosylation inhibition. In conclusion, core fucosylation may regulate the pericyte transition in RIF by modifying both the TGF-ß/Smad and PDGF/ERK pathways. Glycosylation might be a novel "hub" target to prevent RIF.

Mechanisms of pulmonary fibrosis induced by core fucosylation in pericytes.

Pulmonary fibrosis is a common outcome of a variety of pulmonary interstitial diseases, and myofibroblasts are the main culprit for this process. Recent studies have found that pericytes are one of the major sources of myofibroblasts; the transformation of which involves a complex process of activation of TGF-ß/Smad2/3 and PDGFß/Erk signaling pathways. We have reported that the transforming growth factor-ß receptor and platelet-derived growth factor-ß receptor (TGF-ßR I and PDGFßR, respectively) are modified by glycosylation. Thus, we hope to regulate the above-mentioned signal pathways through core fucosylation (CF) catalyzed by α-1,6-fucosyltransferase (FUT8). Previous work has confirmed that TGF-ß1 can induce the transformation of pericytes into myofibroblasts, while FUT8siRNA can inhibit such transformation. In the present study, we used an adenovirus packaging FUT8 shRNA to infect a bleomycin-induced pulmonary fibrosis mouse model and determined the effect of CF on pulmonary fibrosis by analyzing the mechanism of CF-mediated pericyte transformation. Our findings may shed new light on the mechanism of pulmonary interstitial fibrosis and provide a novel therapeutic target for clinical applications.

BPTF promotes tumor growth and predicts poor prognosis in lung adenocarcinomas.

BPTF, a subunit of NURF, is well known to be involved in the development of eukaryotic cell, but little is known about its roles in cancers, especially in non-small-cell lung cancer (NSCLC). Here we showed that BPTF was specifically overexpressed in NSCLC cell lines and lung adenocarcinoma tissues. Knockdown of BPTF by siRNA significantly inhibited cell proliferation, induced cell apoptosis and arrested cell cycle progress from G1 to S phase. We also found that BPTF knockdown downregulated the expression of the phosphorylated Erk1/2, PI3K and Akt proteins and induced the cleavage of caspase-8, caspase-7 and PARP proteins, thereby inhibiting the MAPK and PI3K/AKT signaling and activating apoptotic pathway. BPTF knockdown by siRNA also upregulated the cell cycle inhibitors such as p21 and p18 but inhibited the expression of cyclin D, phospho-Rb and phospho-cdc2 in lung cancer cells. Moreover, BPTF knockdown by its specific shRNA inhibited lung cancer growth in vivo in the xenografts of A549 cells accompanied by the suppression of VEGF, p-Erk and p-Akt expression. Immunohistochemical assay for tumor tissue microarrays of lung tumor tissues showed that BPTF overexpression predicted a poor prognosis in the patients with lung adenocarcinomas. Therefore, our data indicate that BPTF plays an essential role in cell growth and survival by targeting multiply signaling pathways in human lung cancers.

RFPL3 and CBP synergistically upregulate hTERT activity and promote lung cancer growth.

hTERT is the key component of telomerase and its overactivation contributes to maintaining telomere length and cell immortalization. Previously, we identified RFPL3 as a new transcription activator of hTERT in lung cancers. However, the exact mechanism of RFPL3 in mediating hTERT activation and its associated signal regulatory network remain unclear. In this study, we found that RFPL3 colocalized and interacted directly with CBP in the nucleus of lung cancer cells. Immunohistochemical analysis of tissue microarrays of lung cancers revealed the simultaneous overexpression of both RFPL3 and CBP predicted relatively poor prognosis. Furthermore, we confirmed their synergistic stimulation on hTERT expression and tumor cell growth. The binding of RFPL3 to hTERT promoter was reduced markedly when CBP was knocked down by its specific siRNA or suppressed by its inhibitor in lung cancer cells with stable overexpression of RFPL3. When one of the two proteins RFPL3 and CBP was upregulated or downregulated, whereas the another remains unchanged, hTERT expression and telomerase activity were activated or repressed accordingly. In the meantime, the growth of lung cancer cells was also promoted or attenuated accordingly. Furthermore, we also found that RFPL3 coordinated with CBP to upregulate hTERT through the CBP-induced acetylation of RFPL3 protein and their co-anchoring at hTERT promoter region. Collectively, our results reveal a new mechanism of hTERT regulation in lung cancer cells and suggest the RFPL3/CBP/hTERT signaling pathway may be a new targets for lung cancer treatment.

Tanshinone IIA ameliorates bleomycin-induced pulmonary fibrosis and inhibits transforming growth factor-beta-ß-dependent epithelial to mesenchymal transition.

BACKGROUND: Epithelial to mesenchymal transition (EMT) of alveolar epithelial cells occurs in lung fibrotic diseases. Tanshinone IIA (Tan IIA) has been reported to exert anti-inflammatory effects in pulmonary fibrosis. Nonetheless, whether Tan IIA affects lung fibrosis-related EMT remains unknown and requires for further investigations. MATERIALS AND METHODS: A single intratracheal instillation of saline containing bleomycin (BLM; 5 mg/kg body weight) was performed to induce pulmonary fibrosis in Sprague-Dawley rats. Rats receiving an instillation of equivoluminal normal saline served as controls. Then, these rats were given a daily intraperitoneal administration of Tan IIA (15 mg/kg body weight) for 28 d before sacrifice. In vitro, recombinant transforming growth factor-beta 1 (TGF-ß1; 10 ng/mL) was used to treat human alveolar epithelial A549 cells for 48 h. Tan IIA (10 µM) or control DMSO was used to pretreat cells for 2 h before TGF-ß1 stimulation. Rat lung tissue samples and A549 cells were then subjected to further assessments. RESULTS: Tan IIA was noted to alleviate BLM-induced pulmonary collagen deposition and macrophage infiltration in rats. Epithelial-cadherin expression was decreased after BLM stimulation, whereas α-smooth muscle actin, fibronectin, and vimentin were increased. These expression alterations were partially reversed by Tan IIA. Moreover, Tan IIA suppressed BLM-induced increases in TGF-ß1, phosphorylated Smad-2, and -3 in rats. Additionally, pretreatment of Tan IIA inhibited TGF-ß1-triggered EMT, reduced collagen Ⅰ production, and blocked TGF-ß signal transduction in A549 cells. CONCLUSIONS: Our research suggests that Tan IIA mitigates BLM-induced pulmonary fibrosis and suppresses TGF-ß-dependent EMT of lung alveolar epithelial cells.

Ku80 cooperates with CBP to promote COX-2 expression and tumor growth.

Cyclooxygenase-2 (COX-2) plays an important role in lung cancer development and progression. Using streptavidin-agarose pulldown and proteomics assay, we identified and validated Ku80, a dimer of Ku participating in the repair of broken DNA double strands, as a new binding protein of the COX-2 gene promoter. Overexpression of Ku80 up-regulated COX-2 promoter activation and COX-2 expression in lung cancer cells. Silencing of Ku80 by siRNA down-regulated COX-2 expression and inhibited tumor cell growth in vitro and in a xenograft mouse model. Ku80 knockdown suppressed phosphorylation of ERK, resulting in an inactivation of the MAPK pathway. Moreover, CBP, a transcription co-activator, interacted with and acetylated Ku80 to co-regulate the activation of COX-2 promoter. Overexpression of CBP increased Ku80 acetylation, thereby promoting COX-2 expression and cell growth. Suppression of CBP by a CBP-specific inhibitor or siRNA inhibited COX-2 expression as well as tumor cell growth. Tissue microarray immunohistochemical analysis of lung adenocarcinomas revealed a strong positive correlation between levels of Ku80 and COX-2 and clinicopathologic variables. Overexpression of Ku80 was associated with poor prognosis in patients with lung cancers. We conclude that Ku80 promotes COX-2 expression and tumor growth and is a potential therapeutic target in lung cancer.

Tanshinone IIA attenuates bleomycin-induced pulmonary fibrosis in rats.

Idiopathic pulmonary fibrosis is a chronic and progressive fibrotic lung disorder with unknown etiology and a high mortality rate. Tanshinone â…¡A (Tan â…¡A) is a lipophilic diterpene extracted from the Chinese herb Salvia miltiorrhiza Bunge with diverse biological functions. The present study was conducted to evaluate the effects of Tan â…¡A on bleomycin (BLM)­induced pulmonary fibrosis in rats. Rats received an intraperitoneal injection of Tan â…¡A and normal rats were used as controls. Severe pulmonary edema, inflammation and fibrosis were observed in the BLM­treated rats and the counts of total cells, neutrophils and lymphocytes were significantly increased in the bronchoalveolar lavage fluids of those rats. These pathological changes were markedly attenuated by subsequent treatment with Tan â…¡A. In addition, BLM­induced increased expression of tumor necrosis factor­α, interleukin (IL)­1ß, IL­6, cyclooxygenase­2, prostaglandin E2, malondialdehyde, inducible nitric oxide synthase and nitric oxide in rats, which was also suppressed by Tan â…¡A injection. The present findings suggest therapeutic potential of Tan â…¡A for pulmonary fibrosis.

Ret finger protein-like 3 promotes tumor cell growth by activating telomerase reverse transcriptase expression in human lung cancer cells.

In this study, we identified ret finger protein-like 3 (RFPL3) as a hTERT promoter binding protein in lung cancer cells. The high hTERT promoter-binding activity of RFPL3 was detected in lung cancer cells compared to normal cells. Chromatin immunoprecipitation confirmed RFPL3 as a tumor-specific hTERT promoter binding protein. Overexpression of RFPL3 activated hTERT promoter and up-regulated hTERT expression and telomerase activity. Inhibition of RFPL3 expression by siRNA suppressed hTERT promoter activation and telomerase activity. Inhibition of RFPL3 by siRNA or shRNA also significantly inhibited tumor cell growth in vitro and in a xenograft mouse model in vivo. Immunohistochemical analysis of 181 human lung adenocarcinomas specimens showed a significant correlation between RFPL3 and hTERT expression. The overexpression of RFPL3 was also associated significantly with lymph node metastasis. Univariate and multivariate Cox model analyses of NSCLC clinical specimens revealed a strong correlation between RFPL3 expression and overall survival. These results demonstrate that RFPL3 is an important cellular factor which promotes lung cancer growth by activating hTERT expression and may be a potential novel therapeutic target for lung cancer.

Transcriptional coactivator CBP upregulates hTERT expression and tumor growth and predicts poor prognosis in human lung cancers.

Upregulated expression and activation of human telomerase reverse transcriptase (hTERT) is a hallmarker of lung tumorigenesis. However, the mechanism underlying the aberrant hTERT activity in lung cancer cells remains poorly understood. In this study, we found the transcriptional co-activator CBP as a new hTERT promoter-binding protein that regulated hTERT expression and tumor growth in lung adenocarcinoma cells using a biotin-streptavidin-bead pulldown technique. Chromatin immunoprecipitation assay verified the immortalized cell and tumor cell-specific binding of CBP on hTERT promoter. Overexpression of exogenous CBP upregulated the expression of the hTERT promoter-driven luciferase and endogenous hTERT protein in lung cancer cells. Conversely, inhibition of CBP by CBP-specific siRNA or its chemical inhibitor repressed the expression of hTERT promoter-driven luciferase and endogenous hTERT protein as well as telomerase activity. Moreover, inhibition of CBP expression or activity also significantly reduced the proliferation of lung cancer cells in vitro and tumor growth in an xenograft mouse model in vivo. Immunohistochemical analysis of tissue microarrays of lung cancers revealed a positive correlation between CBP and hTERT. Importantly, the patients with high CBP and hTERT expression had a significantly shorter overall survival. Furthermore, CBP was found to interact with and acetylate transactivator Sp1 in lung cancer cells. Inhibition of CBP by CBP-specific siRNA or its chemical inhibitor significantly inhibited Sp1 acetylation and its binding to the hTERT promoter. Collectively, our results indicate that CBP contributes to the upregulation of hTERT expression and tumor growth, and overexpression of CBP predicts poor prognosis in human lung cancers.