HIV-negative plasmablastic lymphoma: report of 8 cases and a comprehensive review of 394 published cases.

BACKGROUND: Human immunodeficiency virus (HIV)-negative plasmablastic lymphoma (PBL) is a rare entity of diffuse large B-cell lymphoma (DLBCL). The clinicopathological features of and optimal treatment for HIV-negative PBL remain largely unknown. METHODS: To gain insight into this distinct lymphoma, we summarized the clinicopathologic characteristics of 8 unpublished HIV-negative PBLs and performed a comprehensive review of 394 published cases. RESULTS: Of the 8 unpublished PBLs, the median patient age was 53.0 years. Four patients presented with stage IV disease. All 8 patients showed a plasma cell-like immunophenotype. Of the six patients who received anthracycline-based chemotherapy, including two who received bortezomib, three patients achieved a continuous complete response, two patients died due to disease progression, and one patient was lost to follow-up. The other two patients achieved continuous complete response after receiving chemotherapy combined with radiotherapy and surgery. Of the 402 patients, the majority were male, with a mean age of 58.0 years. EBV infection was detected in 55.7% of the patients. The median survival times of the patients who received CHOP or CHOP-like regimens and intensive regimens were not reached and 23.0 months, respectively, and the intensive regimen did not improve the survival outcome (P=0.981). Multivariate analysis showed that EBER remained the only independent factor affecting overall survival (OS). CONCLUSION: HIV-negative PBL is a distinct entity with a predilection for elderly and immunosuppressed individuals. Intensive chemotherapy had no apparent survival benefits over the CHOP regimen in terms of OS; the prognosis of this disease is poor with current chemotherapy methods, and treatment remains a challenge.

Cathepsin L interacts with CDK2-AP1 as a potential predictor of prognosis in patients with breast cancer.

Cathepsin L (CTSL) is a lysosomal acid cysteine protease that has been implicated in tumorigenesis and malignant progression. In the present study, the role of CTSL in tumorigenesis and prognosis of breast cancer was evaluated. The prognostic value of CTSL was analyzed using immunohistochemistry in patients with breast cancer, as well as online microarray datasets. CTSL expression was knocked down in the breast cancer cell line T-47D using RNA interference. MTT and colony formation assays were performed to assess the role of CTSL in the proliferation of breast cancer cells. Cell cycle progression and apoptosis were measured using flow cytometry. A physical interaction of CTSL and cyclin dependent kinase 2 associated protein 1 (CDK2-AP1) was determined using a glutathione S-transferase pull-down assay. Endogenous CTSL expression was high in breast cancer cells and exhibited an inverse association with CDK2-AP1 expression; aberrant expression of CTSL in breast cancer tissues predicted an improved clinical outcome and prognosis. In addition, CTSL knockdown decelerated the progression of breast cancer cells by arresting cell cycle progression and increasing apoptosis. Thus, CTSL may be a potential therapeutic target for treating patients with breast cancer.

linc01088 promotes cell proliferation by scaffolding EZH2 and repressing p21 in human non-small cell lung cancer.

AIMS: Non-small cell lung cancer (NSCLC), characterized by extensive metastasis and poor prognosis, is the most common type of lung cancer. Dysregulation of certain lncRNAs is known to be linked to the tumorigenesis of NSCLC. However, the specific roles in NSCLC for many other lncRNAs, such as linc01088, remain largely unknown. MATERIALS AND METHODS: The expression patterns of linc01088, p21 and EZH2 were examined both in NSCLC tissues and cell lines using RT-qPCR assay. CCK-8, colony formation, immunofluorescence staining, and flow cytometry assays were employed to evaluate the effects of linc01088 on NSCLC cell proliferation properties. RNA immunoprecipitation (RIP) assay was performed to determine the direct binding relationship between linc01088 and zeste homolog 2 (EZH2). Western blot and RT-qPCR analysis were performed to assess p21 level within knockdown of either linc01088 or EZH2. Nude mouse subcutaneous NSCLC models were constructed for further validating the effects and mechanisms of linc01088 in vivo. KEY FINDINGS: linc01088 and EZH2 were highly expressed both in NSCLC tissues and cell lines. Knockdown of linc01088 suppressed the proliferation of NSCLC cells, and prolonged the G1 phase while shortened S and G2-M phases. RIP assay revealed the direct binding relationship between linc01088 and EZH2. Knockdown of either linc01088 or EZH2 induced up-regulation of p21 expression, which subsequently inhibited the tumor growth. SIGNIFICANCE: We demonstrated that linc01088 could promote cell proliferation via binding with EZH2 to repress p21, which aggravates the tumorigenesis of NSCLC. Therefore, linc01088 might be a potential oncogene and target for novel anti-tumor therapies.

Cyclin-dependent kinase 1-mediated phosphorylation of YES links mitotic arrest and apoptosis during antitubulin chemotherapy.

YES is a member of the SRC family kinase (SFK) group of non-receptor tyrosine kinases, which are implicated in multiple key cellular processes involved in oncogenesis. Antitubulin agents have been widely used as chemotherapeutics for cancer patients and these drugs arrest cells in mitosis, leading to subsequent cell death. In the present study, we define a mechanism for phospho-regulation of YES that is critical for its role in response to antitubulin agents. Specifically, we found that YES is phosphorylated at multiple sites on its N-terminal unique domain by the cell cycle kinase CDK1 during antitubulin drug-induced mitotic arrest. Phosphorylation of YES occurs during normal mitosis. Deletion of YES causes arrest in prometaphase and polyploidy in a p53-independent manner. We further show that YES regulates antitubulin chemosensitivity. Importantly, mitotic phosphorylation is essential for these effects. In support of our findings, we found that YES expression is high in recurrent ovarian cancer patients. Finally, through expression profiling, we documented that YES phosphorylation affects expression of multiple cell cycle regulators. Collectively, our results reveal a previously unrecognized mechanism for controlling the activity of YES during antitubulin chemotherapeutic treatment and suggest YES as a potential target for the treatment of antitubulin-resistant cancer.

Roles of flotillins in tumors.

The identification and use of molecular biomarkers have greatly improved the diagnosis and treatment of malignant tumors. However, a much deeper understanding of oncogenic proteins is needed for the benefit to cancer patients. The lipid raft marker proteins, flotillin-1 and flotillin-2, were first found in goldfish retinal ganglion cells during axon regeneration. They have since been found in a variety of cells, mainly on the inner surface of cell membranes, and not only act as a skeleton to provide a platform for protein-protein interactions, but also are involved in signal transduction, nerve regeneration, endocytosis, and lymphocyte activation. Previous studies have shown that flotillins are closely associated with tumor development, invasion, and metastasis. In this article, we review the functions of flotillins in relevant cell processes, their underlying mechanisms of action in a variety of tumors, and their potential applications to tumor molecular diagnosis and targeted therapy.

The role of aldehyde dehydrogenase 1A1 in B-cell non-Hodgkin's lymphoma.

Previously we showed that aldehyde dehydrogenase 1A1 (ALDH1A1) is a new mediator for resistance of DLBCL to CHOP and a facility predictor of clinical prognosis. In the present study, knockdown and inhibitor of ALDH1A1 were applied to identify the role of ALDH1A1 in Raji cells. CCK-8 and clone formation assay were applied to determine the CHOP sensitivity and clone formation ability. Caspase colorimetric assay and Annexin V/FITC staining was performed to determine the degree of apoptosis. Western blot analysis was used to detect the NF-κB/STAT3 signaling proteins and apoptotic-associated proteins. Real-time quantitative PCR (RT-PCR) was used to identify the differential expression of ALDH1A1 between NHL patients and healthy donors. We demonstrated that inhibition of ALDH1A1 increased the sensitivity of Raji cells to CHOP, as indicated by increased cytotoxicity, reduced clonogenicity, activated caspase-3/-9, decreased NF-κB/STAT3 signaling and increased pro-apoptosis signaling, ad increased apoptosis rate. Moreover, we found high ALDH1A1 expression was associated with poor prognosis in NHL patients. Our data revealed the critical role of ALDH1A1 in NHL and provides a theoretical basis for the use of ALDH1A1 inhibitors in NHL patients.

Efficacy and tolerance of GELOXD/P-GEMOXD in newly diagnosed nasal-type extranodal NK/T-cell lymphoma: A multicenter retrospective study.

OBJECTIVES: Nasal-type extranodal natural killer NK/T-cell lymphoma (ENKTCL) is a distinct type of non-Hodgkin lymphoma with poor prognosis. This research aimed to evaluate the efficacy and safety of the GELOXD or P-GEMOXD regimens in patients with ENKTCL. METHODS: Newly diagnosed ENKTCL patients treated with either the GELOXD or the P-GEMOXD regimen were identified from three cancer centers between January 2010 and December 2016. Kaplan-Meier and Cox regression analyses were used to calculate overall survival (OS) and progression-free survival (PFS) and to investigate prognostic factors. RESULTS: One hundred and eighty-four cases were identified from three cancer centers. After 1-5 treatment cycles of GELOXD or P-GEMOXD chemotherapy, 155 (84%) patients showed a complete response (CR). The 3-year OS (73.0% vs 38.2%, P = .001) and PFS (72.8% vs 32.4%, P = .000) rates were significantly higher in early-stage patients compared with advanced-stage patients. A multivariate analysis revealed that patient CR status was a significant independent factor in disease prognosis. Grade 3/4 leukopenia occurred in 43 (23.4%) patients. Major non-hematological toxicities included nausea (n = 117, 63.6%) and vomiting (n = 66, 35.9%). CONCLUSIONS: The GELOXD and P-GEMOXD chemotherapy regimens are well tolerated and provide favorable survival outcomes in patients with ENKTCL.

Endoplasmic Reticulum Stress Promotes Autophagy and Apoptosis and Reduces Chemotherapy Resistance in Mutant p53 Lung Cancer Cells.

BACKGROUND/AIMS: Lung cancer (LC) continues to be one of the most prevalent cancers around the world. During this study we aimed to investigate the involvement of endoplasmic reticulum stress (ERS) in autophagy, apoptosis, and chemotherapy resistance of mutant p53 LC cells. METHODS: Immunohistochemistry was employed to help determine the p53 mutation status of cancer cells from 92 primary LC patients, who were subsequently assigned to either the mutant p53 (n = 39) or wild-type p53 group (n = 53). RESULTS: Mutant p53 cells exhibited increased expression of the C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78), and inositol-requiring enzyme-1α (IRE1α). The Mutant p53 cells were also found to be sensitive to chemotherapy and displayed decreased expression of PI3K, Akt, and mTOR. The mutant p53 cell lines were treated with tunicamycin to induce ERS and rapamycin in order to inhibit mTOR. Both agents increased the expression of CHOP, GRP78, IRE1α, LC3-II/LC3-I, Atg5, Atg7, caspase-3, caspase-12, cleaved caspase-3, cleaved caspase-12, as well as decreases in cell proliferation as well as the expression levels of PI3K, Akt, and mTOR. Enhanced levels of cell apoptosis and reduced chemotherapy resistance were also detected. CONCLUSION: The findings of our study suggest that ERS promotes autophagy and apoptosis, while acting to reduce chemotherapy resistance in mutant p53 LC cells by downregulating the PI3K/Akt/mTOR signaling pathway.

TUSC3 induces autophagy in human non-small cell lung cancer cells through Wnt/ß-catenin signaling.

We investigated the effects of tumor suppressor candidate 3 (TUSC3) on autophagy in human non-small cell lung cancer (NSCLC) cells. A total of 118 NSCLC patients (88 males and 30 females) who underwent surgery at our institute were enrolled in the study. Immunohistochemical analysis revealed that TUSC3 protein expression was lower in NSCLC specimens than adjacent normal tissue. Correspondingly, there was greater methylation of TUSC3 in NSCLC than adjacent normal tissue. After transient transfection of A549 NSCLC cells with constructs designed to up-regulate or down-regulate TUSC3 expression, we analyzed the effects of inhibiting the Wnt pathway (XAV939) and autophagy (chloroquine, CQ) on the behavior of NSCLC cells. We also performed TOP/FOP-Flash reporter assays, MTT assays, Annexin V-FITC/propidium iodide staining, and acridine orange staining to evaluate Wnt/ß-catenin signaling, cell proliferation, apoptosis, and autophagy, respectively. Expression of Wnt/ß-catenin pathway components and autophagy-related proteins was analyzed using qRT-PCR and Western blotting. We found that TUSC3 inhibited cell proliferation and promoted both apoptosis and autophagy in A549 cells. In addition, TUSC3 increased expression of autophagy-related proteins. It also increased expression of Wnt/ß-catenin signaling pathway components and promoted nuclear transfer of ß-catenin, resulting in activation of Wnt/ß-catenin signaling. TUSC3 thus induces autophagy in human NSCLC cells through activation of the Wnt/ß-catenin signaling pathway.

Silencing platelet-derived growth factor receptor-ß enhances the radiosensitivity of C6 glioma cells in vitro and in vivo.

Platelet-derived growth factor receptor (PDGFR)-ß is an important tyrosine kinase and its downregulation has been reported to alter the radiosensitivity of glioma cells, although the underlying mechanism is unclear. In order to investigate the effect of PDGFR-ß on the radiosensitivity of glioblastoma, the present study transfected C6 glioma cells with a PDGFR-ß-specific small interfering (si)RNA expression plasmid, and downregulation of the expression of PDGFR-ß in C6 glioma cells was confirmed by western blotting and immunohistochemical analysis. Clone formation assays and xenograft growth curves demonstrated that PDGFR-ß-siRNA enhanced the radiosensitivity of C6 glioma cells in vitro and in vivo. Furthermore, MTT and xenograft growth curves demonstrated that PDGFR-ß-siRNA inhibited the proliferation of C6 glioma cells in vitro and in vivo, and terminal deoxynucleotidyl transferase dUTP nick end-labeling and immunohistochemical analyses demonstrated that PDGFR-ß-siRNA induced apoptosis and inhibited the expression of Ki-67, cyclin B1 and vascular endothelial growth factor in C6 glioma cell xenografts. Taken together, these results suggested that PDGFR-ß may be used as a target for the radiosensitization of glioblastoma.

Overexpression of ANLN contributed to poor prognosis of anthracycline-based chemotherapy in breast cancer patients.

PURPOSE: To investigate the associations of ANLN expression with prognosis of breast cancer and clinical outcome of anthracycline-based chemotherapy. METHODS: This study enrolled 308 breast cancer patients in which 264 of them received anthracycline-based chemotherapy. Immunohistochemistry was used to detect ANLN expression level of the patients. Clinical characteristics of the patients were collected, and associations of ANLN expression with prognosis were analyzed. RESULTS: Our results showed that ANLN expression was associated with survival of breast cancer patients, and it was also related to clinical outcome of patients received anthracycline-based chemotherapy. Breast cancer patients with high expression of ANLN would have poor prognosis and poor clinical outcome to anthracycline-based chemotherapy. CONCLUSION: ANLN could be an independent prognosis predictor for breast cancer, and its expression might be used to predict the anthracycline-based chemotherapy clinical outcome in breast cancer patients.

Pretreatment of Shaoyao Gancao Decoction () alters pharmacokinetics of intravenous paclitaxel in rats.

OBJECTIVE: To investigate the effect of Shaoyao Gancao Decoction (, SGD) on the pharmacokinetics of intravenously administered paclitaxel in rats. METHODS: Paclitaxel was intravenously administered to rats (3 mg/kg) with or without the concomitant administration of SGD (752 mg/kg, a single day or 14 consecutive days pretreatment). The paclitaxel in the serum was quantified using a simple and rapid ultra performance liquid chromatography (UPLC) method for the pharmacokinetic study. The pharmacokinetic parameters were calculated via a non-compartment model using the computer program DAS 2.0. RESULTS: The pharmacokinetic parameters of paclitaxel were significantly altered in response to 14 consecutive days of pretreatment with SGD. The area under the curve (AUC0-t, from 4 820±197 to 4 205±186 ng·mL-1·-1) and AUC0-∞ (from 5 237±280 to 4 514±210 ng·mL-1·-1) significantly decreased in response to the 14-day pretreatment with SGD. The values of Vdss (L/kg) were 10.74±1.08 and 9.35±0.49, those of CL (L/kg) were 0.67±0.03 and 0.57±0.03 and the t1/2 (h) values were 11.17±0.84 and 11.32±0.93, respectively, for the 14-day SGD pretreatment and intravenous paclitaxel alone. The AUC0-t and AUC0-∞ values decreased by 13% and 14% (P<0.01), respectively. The area under the curve decreased signifificantly (P<0.01), and the total clearance increased by 1.2-fold (P<0.01), after 14 consecutive days of pretreatment with SGD. A single-day pretreatment with SGD did not signifificantly affect the pharmacokinetic parameters of paclitaxel. CONCLUSIONS: SGD administration for 14 consecutive days increased the metabolism of paclitaxel, while a 1-day pretreatment had little effect. The results would contribute important information to the study on interaction between Chinese medicines and chemotherapy and also help to utilize SGD better in the adjunctive therapy of cancer patients.

Multiple Roles of WNT5A in Breast Cancer.

Breast cancer is one of the most common malignant tumors of women. Modern combinatorial therapeutic regimens can reduce patient tumor burdens to undetectable levels, yet in many cases these tumors will relapse. Understanding of breast cancer biology, developing more potent therapeutic approaches, and overcoming resistance are of great importance. WNT5A is a non-canonical signaling member of the WNT family. Its role in breast cancer still remains unclear. Most of the evidence shows that WNT5A is a suppressor in breast cancer and loss of its expression is associated with poor prognosis, while some evidence suggests the tumorigenicity of WNT5A. WNT signaling molecules are potent targets for treatment of cancer. Therefore, understanding the role of WNT5A in breast cancer may provide new ideas and methods for breast cancer treatment. We review the evidence concerning WNT5A and breast cancer involving the signaling pathways and the molecular-targeted therapy of WNT5A. Our results show that the role WNT5A plays depends on the availability of key receptors and intercellular interactions among different cell types.

Inhibition of microRNA-196a might reverse cisplatin resistance of A549/DDP non-small-cell lung cancer cell line.

We aimed to explore the possible mechanism of microRNA-196a (miR-196a) inhibition and reversion of drug resistance to cisplatin (DDP) of the A549/DDP non-small-cell lung cancer (NSCLC) cell line. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect expression differences of miR-196a in the drug-resistant A549/DDP NLCLC cell line and the parental A549 cell line, and expressions of miR-196a in the A549/DDP NLCLC cell line transfected with miR-196a inhibitor (anti-miR-196a group) and the miR-196a negative control (miR-NC) group and blank group (without transfection). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was applied in examining the cell viability of A549/DDP cell line before and after transfection. Clonogenic assay was used to detect cell proliferation ability. Flow cytometry was applied in detecting apoptosis rate of assayed tumor cell and rhodamine-123 changes in cells. Western blot was applied in detecting proteins of drug-resistant related gene in A549/DDP cell line. Significantly higher expression of miR-196a was detected in the drug-resistant A549/DDP cell line than that in the parental A549 cell line (P < 0.05). However, miR-196a expression in the anti-miR-196a group decreased obviously compared to that in the blank group and the miR-NC group (both P < 0.05); The value of IC50 in the anti-miR-196a group showed remarkably lower than that in the blank group and the miR-NC group (both P < 0.05); Rh-123 absorbing ability in the anti-miR-196a group increased 2.51 times and 2.49 times respectively compared to that in the blank group and the miR-NC group (both P < 0.05). No statistical differences in the apoptosis rate of A549/DDP cell line in the early stage were found among the three groups (all P > 0.05), but the late-stage apoptosis rate in the anti-miR-196a group was significantly higher than that in the blank group and the miR-NC group (both P < 0.05); The expressions of human multidrug resistance 1 (MDR1), multidrug resistance protein 1 (MRP1), excision repair cross-complementation 1 (ERCC1), survivin, and B cell lymphoma 2 (Bcl-2) decreased significantly while RhoE increased significantly in the anti-miR-196a group than the blank group and the miR-NC group (all P < 0.05). Inhibition of miR-196a could reverse cisplatin resistance of A549/DDP cell lines, which might relate with inhibition of drug efflux, down-regulation of drug-resistant protein expression, cell apoptosis, and cell proliferation suppression.

S-1 plus cisplatin versus fluorouracil plus cisplatin in advanced gastric or gastro-esophageal junction adenocarcinoma patients: a pilot study.

The safety and efficacy of S-1 plus cisplatin in Chinese advanced gastric cancer patients in first line setting is unknown. In this pilot study, patients with advanced gastric or gastro-esophageal junction adenocarcinoma were enrolled and randomly assigned in a 1:1 ratio to receive S-1 plus cisplatin (CS group) or 5-FU plus cisplatin (CF group). The primary endpoint was time to progression (TTP). Secondary end points included overall survival (OS) and safety. This study was registered on ClinicalTrials. Gov, number NCT01198392. A total of 236 patients were enrolled. Median TTP was 5.51 months in CS group compared with 4.62 months in CF group [hazard ratio (HR) 1.028, 95% confidential interval (CI) 0.758-1.394, p = 0.859]. Median OS was 10.00 months and 10.46 months in CS and CF groups (HR 1.046, 95%CI 0.709-1.543, p = 0.820), respectively. The most common adverse events in both groups were anemia, leukopenia, neutropenia, nausea, thrombocytopenia, vomiting, anorexia and diarrhea. We find that S-1 plus cisplatin is an effective and tolerable option for advanced gastric or gastro-esophageal junction adenocarcinoma patients in China.

ALDH1A1 mediates resistance of diffuse large B cell lymphoma to the CHOP regimen.

Although there have been substantial advances in our knowledge of the resistance of diffuse large B cell lymphoma (DLBCL) to chemotherapy, there are few efficient treatment strategies for recurrent/refractory DLBCL. The aim of this study was to investigate the role of aldehyde dehydrogenase (ALDH) 1A1 in the resistance of diffuse large B cell lymphoma to the chemotherapeutic mixture consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). The involvement of ALDH1A1 in DLBCL was elucidated by knockdown and pharmacologic inhibition; Cell Counting Kit-8 (CCK-8) and clone formation assays were used to determine its role in CHOP sensitivity and clone formation ability. Caspase colorimetric assay was used to measure the extent of apoptosis. Western blot analysis was used to measure signal transducer and activator of transcription 3 (STAT3)/nuclear factor kappa B (NF-κB) signaling proteins, and quantitative real-time PCR (RT-PCR) was used to measure the differential expression of ALDH1A1 of DLBCL patients and healthy donors. ALDH1A1 showed a 5.64-fold higher expression in malignant B cells than in normal B cells. Diethylaminobenzaldehyde (DEAB) decreased the half maximal inhibitory concentration (IC50) of the CHOP regimen in Farage cells from 344.78 ± 65.75 to 183.88 ± 49.75 ng/ml (P = 0.004). Both knockdown and inhibition of ALDH1A1 reduced clonogenicity, increased caspase-3/caspase-9 activity, and attenuated the phosphorylation status of STAT3/NF-κB. The prognosis of patients with a high level of ALDH1A1 expression was poor compared with that of patients with low levels of expression (P = 0.044). ALDH1A1 is a new mediator for resistance of DLBCL to CHOP; it is a predictor of clinical prognosis and may serve as a potential target to improve chemotherapy responsiveness of human DLBCL.

[Metabolic changes in abnormal savda patients with different types of tumor: a clinical observation].

OBJECTIVE: To explore in vivo metabolic changes in abnormal savda patients with different types of tumor. METHODS: A total of 142 abnormal savda patients with common cancer types were enrolled in this study, and 50 healthy volunteers were recruited as the control group. For each sample, the H Nuclear Magnetic Resonance (NMR) based metabonomic analysis was performed. The free attenuation signal was computed subsection integral. Data obtained were analyzed by the Orthogonal Partial Least-Squares Discriminant Analysis (OPLS-DA). RESULTS: Compared with the control group, leucine, isoleucine, valine, histidine, phenylalanine, tyrosine, alanine, creatine, lactic acid, inositol, alpha-and beta-glucose, unsaturated lipids, very low density lipoprotein (VLDL) significantly decreased (P <0.05), while glycoprotein and carnitine significantly increased (P <0. 05) in the abnormal Savda group. CONCLUSION: Abnormal savda patients with different types of tumor had similar metabonomics changes.

High expression of Toll-like receptor 5 correlates with better prognosis in non-small-cell lung cancer: an anti-tumor effect of TLR5 signaling in non-small cell lung cancer.

PURPOSE: Toll-like receptor 5 (TLR5) is a pattern recognition receptor and plays key roles in inflammatory responses against pathogen infection. Recent evidence suggests that TLR5 is expressed in a wide variety of tumors and exhibits either pro-tumor or anti-tumor activities. In this study, we explored expression of TLR5 in the context of non-small-cell lung cancer (NSCLC) and evaluated the effects of TLR5 signaling in NSCLC cells. METHODS: The lung carcinoma samples were collected from 113 patients diagnosed as NSCLC at Tumor Hospital of Xiangya School of Medicine from January 2005 to December 2008. Immunohistochemistry was performed for TLR5 and the protein expression score was quantified using an established scoring system. Kaplan-Meier survival curves were generated for disease-free survival (DFS) and overall survival (OS) in all patients. TLR5 expression levels were correlated with DFS and OS using univariate and multivariate Cox regression analysis. Expression and subcellular localization of TLR5 were analyzed in NSCLC cell lines including SPC-A1, A549, H1975, and H1299 cells. Activation of TLR5 signaling pathway by flagellin was characterized by western blotting. Effects of flagellin on NSCLC cell proliferation, anchorage-independent growth, migration, and invasion were analyzed by BrdU incorporation assay, soft agar colony formation assay, wound-healing migration assay, and transwell invasion assay, respectively. RESULTS: High expression of TLR5 was significantly associated with better prognosis in patients with NSCLC. We further demonstrated that activation of TLR5 by flagellin in NSCLC cells inhibited cell proliferation, migration, and invasion in vitro. CONCLUSION: TLR5 may serve as a potential therapeutic target in NSCLC patients.