Reirradiation with stereotactic body radiotherapy for primary or secondary lung malignancies: Tumor control probability and safety analyses.

BACKGROUND: Reirradiation with stereotactic body radiotherapy (SBRT) for patients with primary or secondary lung malignancies represents an appealing definitive approach, but its feasibility and safety are not well defined. The purpose of this study was to investigate the tumor control probability (TCP) and toxicity for patients receiving reirradiation with SBRT. PATIENTS AND METHODS: Eligible patients with recurrence of primary or secondary lung malignancies from our hospital were subjected to reirradiation with SBRT, and PubMed- and Embase-indexed articles were reviewed. The patient characteristics, pertinent SBRT dosimetric details, local tumor control, and toxicities were extracted. The logistic dose-response models were compared for TCP and overall survival (OS) in terms of the physical dose and three-, four-, and five-fraction equivalent doses. RESULTS: The data of 17 patients from our hospital and 195 patients extracted from 12 articles were summarized. Reirradiation with SBRT yielded 2-year estimates of 80% TCP for doses of 50.10 Gy, 55.85 Gy, and 60.54 Gy in three, four, and five fractions, respectively. The estimated TCP with common fractionation schemes were 50%, 60%, and 70% for 42.04 Gy, 47.44 Gy, and 53.32 Gy in five fractions, respectively. Similarly, the 2-year estimated OS was 50%, 60%, and 70% for 41.62 Gy, 46.88 Gy, and 52.55 Gy in five fractions, respectively. Central tumor localization may be associated with severe toxicity. CONCLUSIONS: Reirradiation with SBRT doses of 50-60 Gy in 3-5 fractions is feasible for appropriately selected patients with recurrence of peripheral primary or secondary lung malignancies, but should be carefully considered for centrally-located tumors due to potentially severe toxicity. Further studies are warranted for optimal dose/fractionation schedules and more accurate selection of patients suitable for reirradiation with SBRT.

[Port-only 4-Arms Robotic Segmentectomy Under Artificial Pneumothorax].

BACKGROUND: At present, robotic surgery is widely used in thoracic surgery, which has higher maneuverability, precision, and stability, especially for small space complex operations and reconstructive surgery. The advantages of robotic lung segment resection under full orifice artificial pneumothorax are obvious. METHODS: Based on a large number of clinical practices, we established a set of surgical methods for 4-arm robotic lung segment resection under a port-only artificial pneumothorax. 98 cases of robotic lung segment resection were performed with this method from January 2019 to August 2022. The clinical experience was summarized. RESULTS: Robotic lung segment resection under port-only artificial pneumothorax has obvious advantages in the anatomy of lung segment vessels and bronchi. It is characterized by less bleeding, shorter operation time, adequate exposure, and flexible operation. CONCLUSIONS: This surgical model we propose optimizes the operation mode and technique of lung segment resection, makes each step procedural, reduces collateral damage, and is easy to learn and master, which is believed to cure more lung cancer patients with less trauma.

The Indicative Value of Serum Tumor Markers for Metastasis and Stage of Non-Small Cell Lung Cancer.

Objective: This study aimed to explore the roles of serum tumor markers for metastasis and stage of non-small cell lung cancer (NSCLC). Methods: This study recruited 3272 NSCLC patients admitted to the Tianjin Union Medical Center and the Tianjin Medical University Cancer Institute and Hospital. The predictive abilities of some serum tumor markers (carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag), cytokeratin-19 fragment (CYFRA 21-1), neuron-specific enolase (NSE), pro-gastrin-releasing peptide (ProGRP), total prostate-specific antigen (TPSA) and carbohydrate antigen 199 (CA199)) for NSCLC metastasis (intrapulmonary, lymphatic and distant metastasis) and clinical stage were analyzed. Results: Tumor markers exhibited different numerical and proportional distributions in NSCLC patients. Elevated CEA, CYFRA 21-1 and CA199 levels were indicative of tumor metastasis and stage. Increased CEA and CA199 provided an accurate prediction of intrapulmonary and distant metastasis with the area under the receiver operator characteristic curve (AUC) of 0.69 both (p < 0.001); Increased CEA, CYFRA 21-1 and CA199 provided an accurate prediction of lymphatic metastasis with the AUC of 0.62 (p < 0.001). Conclusion: Combined detection of serum tumor markers can indicate tumor metastasis and stage in NSCLC patients.

Risk-adapted stereotactic body radiotherapy for patients with cervical spinal metastases.

Owing to the complex anatomical structure and biomechanics, the current standard palliative treatments for cervical spinal metastases are associated with a high risk of recurrence and complications. Stereotactic body radiotherapy (SBRT) can provide radical dose to tumors while protecting normal organs to the maximum extent. However, the efficacy and safety of SBRT for cervical spinal metastases is not well characterized. Data from 71 patients with cervical spine metastases who were treated with SBRT using CyberKnife between 2006 and 2021 were obtained from our prospectively maintained database. Primary endpoint was pain response at 12 weeks following SBRT completion; secondary endpoints included local control (LC), overall survival (OS), and adverse events. Standard-risk patients were planned to receive 30 Gy (range 21-36) with median fractions of 3 (range 1-3) and high-risk patients 35 Gy (range 24-50) with median fractions of 5 (range 4-5) according to the spinal cord and esophagus dose constraints. The median follow-up time was 17.07 months (range 3.1-118.9). After 12 weeks of SBRT completion, 54 (98.2%) of 55 patients with baseline pain achieved pain response and 46 (83.6%) achieved complete pain response. LC rates were 93.1% and 90% at 1 year and 2 year, respectively. The 1-year and 2-year OS rates were 66.2% and 37.4%, respectively. Eight patients experienced grades 1-4 adverse events (six vertebral compression fracture [VCF], five of them had VCF before SBRT; and two hemiparesis). No grade 5 adverse events were observed. Therefore, risk-adapted SBRT for cervical spine metastases achieved high pain control and LC rates with acceptable adverse events.

Identification of a DNA damage repair gene-related signature for lung squamous cell carcinoma prognosis.

BACKGROUND: DNA damage repair (DDR) plays a role in the tumorigenesis and progression of lung squamous cell carcinoma (LUSC), but the predictive value of DDR in LUSC has not been fully elucidated. METHODS: The LUSC datasets were retrieved from the Cancer Genome Atlas databases. Univariate Cox regression and least absolute shrinkage and selection operator regression were integrated to identify critical genes and construct a DDR gene signature. We performed Kaplan-Meier (KM) curve to compare the overall survival (OS) between the two groups based on DDR signature and used the CIBERSORT tool to compare the immune cell composition. Further gene set enrichment analysis (GSEA) was performed on the differential expressed genes. RESULT: We established the DDR-related gene signature on LUSC. KM curve showed the low-risk group had a better prognosis than the high-risk group in the training set (p = 0.022673) and the complete set (p = 0.003201). The area under receiver operating characteristic curve for OS was 0.98, 0.96, and 0.97 in the training dataset, testing dataset, and the complete dataset, respectively. The composition of immune cells was different between the high- and low-risk group. The GSEA result suggests that genes of the patients in low-risk group were mainly enriched in the DNA adducts; drug metabolism-cytochrome P450, metabolism of xenobiotics by cytochrome P450. CONCLUSION: This study identified DDR-associated potential biomarkers related to overall survival of LUSC and establishes the DDR-associated gene signature.

Extracellular vesicles promotes liver metastasis of lung cancer by ALAHM increasing hepatocellular secretion of HGF.

Tumor-derived extracellular vesicles (EVs) are involved in tumor metastasis. Highly enriched lncRNA-ALAHM was identified from serum EVs of lung adenocarcinoma (LUAD) patients with liver metastasis by high-throughput sequencing. A mouse model of in situ lung cancer was used to determine the effect of ALAHM in LUAD cell EVs on liver metastasis. The effects of ALAHM on hepatocyte paracrine HGF as well as proliferation, invasion, and migration of LUAD cells were observed in vitro. As results, ALAHM expression in LUAD cell EVs was significantly increased. LUAD-cell-derived EVs overexpressing ALAHM significantly promoted lung cancer liver metastasis in model mice. ALAHM of LUAD cell EVs also promotes hepatocyte parasecretion of HGF by binding with AUF1 and increases the proliferation, invasion, and migration of LUAD cells. Thus, LUAD-cell-derived EVs containing ALAHM causes increasing HGF and promoting liver metastasis of LUAD cells.

Multiple calcifying fibrous tumor of the pleura: A case report.

Calcifying fibrous tumor of the pleura (CFTP) is a rare benign tumor of the thoracic cavity. Due to the low incidence of CFPT, it is prone to be misdiagnosed because intraoperative analysis of frozen section is a challenge for pathologists. At present, it is difficult to distinguish this tumor from other benign thoracic tumors based on radiographic features. Therefore, surgical resection is the best method for definite diagnosis and treatment.

FATS regulates polyamine biosynthesis by promoting ODC degradation in an ERß-dependent manner in non-small-cell lung cancer.

Polyamine biosynthesis is an essential metabolic pathway for cell growth and differentiation in non-small-cell lung cancer (NSCLC). Fragile-site associated tumour suppressor (FATS) is a novel gene involved in cancer. The results of our previous study showed that FATS-mediated polyubiquitination of p53 promotes the activation of p53 in response to DNA damage; however, little is known about the role of FATS in metabolic reprogramming in NSCLC. In the present study, FATS was observed to be significantly downregulated in NSCLC tissues compared with paired adjacent normal tissues and was associated with the survival of NSCLC patients. We further showed that the presence of the tumour suppressor FATS in NSCLC cells led to apoptosis by inducing pro-death autophagy. In addition, FATS was shown to function as a suppressor of polyamine biosynthesis by inhibiting ornithine decarboxylase (ODC) at the protein and mRNA levels, which was partially dependent on oestrogen receptor (ER). Furthermore, FATS was observed to bind to ERß and translocate to the cytosol, leading to ODC degradation. The findings of our study demonstrate that FATS plays important roles in polyamine metabolism in NSCLC and provides a new perspective for NSCLC progression.

Sorting and gene mutation verification of circulating tumor cells of lung cancer with epidermal growth factor receptor peptide lipid magnetic spheres.

BACKGROUND: This study aimed to identify an efficient, simple, and specific method of detecting mutations in the epidermal growth factor receptor (EGFR) gene in isolated lung cancer circulating tumor cells (CTCs) and to improve the ability to obtain tumor tissue clinically. METHODS: EGFR peptide lipid magnetic spheres (EG-P-LMB) were prepared by reverse evaporation, and characterization and cell capture efficiency assessed. The peripheral blood samples of 30 lung cancer patients were isolated and identified with the EG-P-LMB using 20 healthy volunteers as controls. Finally, the isolated CTCs were tested for EGFR gene mutations, and the tissue samples selected for comparison. RESULTS: The prepared magnetic spheres had a smaller particle size and higher stability according to the particle size potential test. Their morphology was homogeneous by atomic force observation, and the UV test showed that there were peptides on the surface. The separation efficiency of EG-P-LMB was greater than 90% in PBS and greater than 80% in the blood simulation system. Compared with the tissue sample results, the positive rate of EGFR gene mutations was 94%. The CTC test results of 27 patients were consistent with the tissue test results of the corresponding patients, and the consistency with the tissue comparison test results was 90% (27/30). CONCLUSIONS: EG-P-LMB can effectively capture CTCs in the peripheral blood of patients with lung cancer. CTC detection can accurately identify mutations in the EGFR gene and improve the ability to obtain tumor tissue in clinical practice. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: EG-P-LMB can effectively capture CTCs in the peripheral blood of patients with lung cancer. CTC detection can accurately identify mutations in the EGFR gene and improve the ability to obtain tumor tissue in clinical practice. WHAT THIS STUDY ADDS: This study added EGFR peptide lipid magnetic spheres to capture CTCs in the blood. Genetic testing was performed and compared with tissues. It solves the problem of clinically difficult tumor tissue sampling.

Platelet-lymphocyte ratio is an independent prognostic factor in patients with ALK-positive non-small-cell lung cancer.

AIM: As the prognostic value of the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) is unclear in patients with ALK-positive non-small-cell lung cancer (NSCLC), this study assessed the importance of these factors was in this patient subset. PATIENTS & METHODS: In 173 patients with primary ALK-positive NSCLC at pathological stages I-IV, neutrophil, platelet, lymphocyte, D-dimer and eosinophil levels were recorded before starting treatment. RESULTS: The patients' median NLR and PLR values were 2.10 and 127.69, respectively. Univariate analyses showed that NLR and PLR values, the D-dimer level and the eosinophil count were all associated with survival. Although multivariate analysis showed PLR to be an independent prognostic factor for overall survival (p = 0.018), NLR was not. CONCLUSION: PLR is an independent prognostic factor in ALK-positive NSCLC.

Claudin-1 correlates with poor prognosis in lung adenocarcinoma.

BACKGROUND: This study was conducted to investigate the clinical significance of claudin-1 (CLDN1) expression in patients with lung adenocarcinoma. METHODS: We examined CLDN1 protein expression by immunohistochemistry in a tissue microarray from 258 patients with lung adenocarcinoma. We investigated messenger ribonucleic acid (mRNA) expression in H358 (formerly bronchioloalveolar carcinoma) and lung adenocarcinoma cell lines (A549) by real-time reverse transcriptase-polymerase chain reaction. RESULTS: Multivariate analysis showed that prognostic factors for lung adenocarcinoma were histologic type, CLDN1, T stage and N stage. Patients with positive CLDN1 expression had a poorer prognosis than patients with negative CLDN1 expression. CLDN1 expression was correlated with Ras and epidermal growth factor receptor (EGFR) expression. Patients with positive expressions of both CLDN1 and Ras/EGFR had a poorer prognosis than patients with CLDN1 (+) Ras/EGFR(-) or CLDN1 (-) Ras/EGFR(+) and patients with negative expressions of both CLDN1 and Ras/EGFR. CLDN1 mRNA expression was lower in the H358 compared with the lung adenocarcinoma cell line (A549). CONCLUSION: The combination of CLDN1 and Ras/EGFR is a valuable independent prognostic predictor for lung adenocarcinoma.

Significance of interstitial tumor-associated macrophages in the progression of lung adenocarcinoma.

Stepwise progression from adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) to lepidic predominant adenocarcinoma (LPA) was proposed by various scholars. Interstitial tumor-associated macrophages (TAMs) and various potential chemokines involved in the progression from AIS/MIA to LPA were hypothesized. In the present study, immunohistochemistry or immunofluorescent double staining was used to detect the expression of the TAMs marker cluster of differentiation (CD) 68, tumor-derived colony-stimulating factor (CSF)-1, interleukin (IL)-6, matrix metalloproteinase (MMP)-2, E-cadherin and Snail in lung adenocarcinoma specimens, including AIS/MIA, LPA and other types. It was observed that infiltrating TAMs were negatively associated with the prognosis of patients, and that the infiltration degree of interstitial TAMs was higher in LPA than that in AIS/MIA. In addition, E-cadherin, Snail and MMP-2 expression were significantly correlated with the infiltration degree of TAMs. Survival analysis revealed that co-expression of CD68, CSF-1 and IL-6 was an independent prognostic factor. Stratified analysis demonstrated that, in AIS/MIA patients, there was a statistically significant difference between the number of TAMs (TAMs ≤25 and TAMs >25) in the CD68+CSF-1+IL-6+ group compared with other groups (including CD68+CSF-1-IL-6-, CD68+CSF-1+IL-6-, CD68+CSF-1-IL-6+ and CD68- groups). By contrast, in patients with TAMs >25 and in patients with positive CD68, CSF-1 and IL-6 expression, the survival rates were not significantly different between AIS/MIA and LPA. These results suggested that co-expression of TAMs marker CD68, CSF-1 and IL-6 may be a valuable independent prognostic predictor in lung adenocarcinoma. TAMs may facilitate AIS/MIA progression to LPA, which may be closely associated with the induction of the epithelial-mesenchymal transition.

[Advances in Research of Osteopontion and Its Receptor CD44v in Tumor Invasion and Metastasis].

Osteopontin (OPN) is a multifunctional, extracellular matrix-associated, secretory, glyco-protein. It can be used as an adhesion protein involved in tumor cell adhesion,migration; but also as a cytokine, promoting tumor angiogenesis, evading immune surveillance and inhibiting cellular apoptosis. CD44v glycoprotein, is one of the cell surface adhesion molecule that mediates cell-matrix and cell-cell interactions. Extensive research has suggested the important role of OPN in regulating signaling pathways that contribute to tumor progression and metastasis, and the serum level is associated with the prognosis of various malignancies. Therefore, clarifying OPN in the molecular mechanisms of tumor progression and its signaling pathway contributes to seeking a novel anti-cancer therapy.

[Expression of colony-stimulating factor 1 in lung adenocarcinoma and its prognostic implication].

OBJECTIVE: This study aimed to explore the expression of tumor-derived colony-stimulating factor 1 (CSF1), its prognostic significance and underlying related mechanisms in resected lung adenocarcinoma (ADC). METHODS: Immunohistochemistry and tissue microarray were used to detect the expression of CSF1, epidermal growth factor receptor (EGFR), and CD68 in 266 patients with lung adenocarcinoma treated in our department between 2004 and 2008. RESULTS: In the 266 ADC cases, the positive rates of expression of CSF1, EGFR and CD68 proteins were 56.4%, 42.1% and 81.2%, respectively. The expression level of CSF1 was positively correlated with TNM stage, number of involved nodal stations, tumor recurrence and EGFR expression (P<0.05). Univariate analysis indicated that TNM stage, number of involved lymph nodes, number of involved nodal stations, CSF1 expression, the combination of CSF1/EGFR and co-expression of CSF1/CD68/EGFR were statistically significant for prognosis (P<0.05). The results of multivariate analysis showed that TNM stage, co-expression of CSF1/EGFR and CSF1/CD68/EGFR were significant and independent risk factors for survival (P<0.05). Correlational analysis showed that expression of CSF1 and EGFR in the tumors was positively correlated to the degree of infiltration of interstitial tumor-associated macrophages (TAMs) (respectively; P<0.05). CONCLUSIONS: The expression of CSF1 indicates a poor prognosis in postoperative lung adenocarcinoma. Co-expression of CSF1 and EGFR may be a valuable independent prognostic predictor, and its mechanism is probably involved in the interaction of cancer cells and TAMs in the progression of lung adenocarcinoma.

Osteopontin-expressing macrophages in non-small cell lung cancer predict survival.

BACKGROUND: Tumor-associated macrophages (TAMs) are a major component of leukocyte infiltration in the tumor microenvironment. Osteopontin is related to tumor metastasis and proliferation. Osteopontin is expressed not only by tumor cells but also by TAMs. The purpose of the current study was to assess the prognostic significance of osteopontin expressed by TAMs (TOPN) in patients with non-small cell lung cancer. METHODS: Tissue microarray was used to detect the expression of TOPN, TAMs, and microvascular density in 159 patients with non-small cell lung cancer undergoing complete pulmonary resection in our hospital between 2003 and 2006. The correlations between TOPN, TAMs, and clinicopathologic data were analyzed with χ(2) tests. Quantitation of TAMs or TOPN and microvascular density analyses was performed using Bonferroni correction and the Student's t test. The prognostic value of TOPN was evaluated by univariate Kaplan-Meier survival analysis and multivariate Cox proportional hazard model analysis. RESULTS: In the recurrence and metastasis group, microvascular density was higher than that in the control group (14.4 ± 1.06 versus 8.9 ± 1.02; p = 0.0002). In the TOPN-positive group, microvascular density was increased compared with that in the TOPN-negative group (14.3 ± 1.37 versus 10.7 ± 0.91; p = 0.0273). Osteopontin expressed by TAMs was an independent predictor for overall survival (p = 0.017) and disease-free survival (p < 0.001), especially for stage I non-small cell lung cancer. The 6-year overall and disease-free survival rates in TOPN-positive patients were 22.64% and 16.98%, respectively, which were significantly lower than those of TOPN-negative patients (50.00% and 39.62%, respectively). CONCLUSIONS: Osteopontin expressed by TAMs is a valuable independent predictor of tumor recurrence and survival in patients with non-small cell lung cancer.

Prognostic value analysis of mutational and clinicopathological factors in non-small cell lung cancer.

INTRODUCTION: Targeting activating oncogenic driver mutations in lung adenocarcinoma has led to prolonged survival in patients harboring these specific genetic alterations. The prognostic value of these mutations has not yet been elucidated. The prevalence of recently uncovered non-coding somatic mutation in promoter region of TERT gene is also to be validated in lung cancer. The purpose of this study is to show the prevalence, association with clinicalpathological features and prognostic value of these factors. METHODS: In a cohort of patients with non-small cell lung cancer (NSCLC) (n = 174, including 107 lung adenocarcinoma and 67 lung squamous cell carcinoma), EGFR, KRAS, HER2 and BRAF were directly sequenced in lung adeoncarcinoma, ALK fusions were screened using FISH (Fluorescence in situ Hybridization).TERT promoter region was sequenced in all of the 174 NSCLC samples. Associations of these somatic mutations and clinicopathological features, as well as prognostic factors were evaluated. RESULTS: EGFR, KRAS, HER2, BRAF mutation and ALK fusion were mutated in 25.2%, 6.5%, 1.9%, 0.9% and 3.7% of lung adenocarcinomas. No TERT promoter mutation was validated by reverse-sided sequencing. Lung adenocarcinoma with EGFR and KRAS mutations showed no significant difference in Disease-free Survival (DFS) and Overall Survival (OS). Cox Multi-variate analysis revealed that only N stage and HER2 mutation were independent predictors of worse overall survival (HR = 1.653, 95% CI 1.219-2.241, P = 0.001; HR = 12.344, 95% CI 2.615-58.275, P = 0.002). CONCLUSIONS: We have further confirmed that TERT promoter mutation may only exist in a very small fraction of NSCLCs. These results indicate that dividing lung adenocarcinoma into molecular subtypes according to oncogenic driver mutations doesn't predict survival difference of the disease.

Interstitial tumor-associated macrophages combined with tumor-derived colony-stimulating factor-1 and interleukin-6, a novel prognostic biomarker in non-small cell lung cancer.

OBJECTIVES: Recent experimental evidence has indicated that interstitial tumor-associated macrophages (TAMs), tumor-derived macrophage colony-stimulating factor (also known as CSF-1), and interleukin-6 (IL-6) interact in the pathogenesis of malignant epithelial tumors, including lung cancer. The present study aimed to explore their relationship and prognostic significance in surgically resected non-small cell lung cancer (NSCLC). METHODS: Tissue microarray and immunohistochemistry were used to detect the expression of CSF-1, IL-6, and CD68-positive TAMs in 417 patients with NSCLC undergoing complete pulmonary resection from 2003 to 2008. Their correlations and clinicopathologic data were analyzed using chi-square testing. Their prognostic values were evaluated by univariate Kaplan-Meier survival analysis and multivariate Cox proportional hazard model analysis. RESULTS: The expression of CSF-1 and IL-6 in NSCLC correlated positively with the infiltration degree of TAMs in the tumor stroma (r=0.184 and r=0.196, respectively; P<.001). The expression of both CSF-1 and IL-6 was statistically significant for survival (P<.001). Nevertheless, no such relationship was observed for CD68 in the tumor stroma (P>.05). When CSF-1 and/or IL-6 and CD68 were taken into consideration together, the result became statistically significant. Multivariate analysis showed that co-expression of CD68, CSF-1, and IL-6 remained the most significant and independent prognostic factor for survival (P<.05) but not the combinations of CSF-1 and IL-6, CD68 and CSF-1, or CD68 and IL-6 (P>.05). The 5-year survival rate in the CD68-negative and CSF-1- and IL-6-positive group was better than the rate in the CD68, CSF-1-, and IL-6-positive group (P<.05). CONCLUSIONS: The combination of CD68 plus TAMs, CSF-1, and IL-6 is very likely to be a valuable independent predictor of survival in patients with NSCLC. Perhaps co-expression of CSF-1 and IL-6 induces interstitial TAMs to shift toward the tumor-promoting phenotype.

Expressions of CLDN1 and insulin-like growth factor 2 are associated with poor prognosis in stage N2 non-small cell lung cancer.

BACKGROUND: Patients with single station mediastinal lymph node (N2) non-small cell lung cancer (NSCLC) have a better prognosis than those with multilevel N2. The molecular factors which are involved in disease progression remain largely unknown. The purpose of this study was to investigate gene expression differences between single station and multilevel N2 NSCLC and to identify the crucial molecular factors which are associated with progress and prognosis of stage N2 NSCLC. METHODS: Gene expression analysis was performed using Agilent 4×44K Whole Human Genome Oligo Microarray on 10 freshfrozen lymph node tissue samples from single station N2 and paired multilevel N2 NSCLC patients. Real-time reverse transcription (RT)-PCR was used to validate the differential expression of 14 genes selected by cDNA microarray of which four were confirmed. Immunohistochemical staining for these validated genes was performed on formalin-fixed, paraffinembedded tissue samples from 130 cases of stage N2 NSCLC arranged in a high-density tissue microarray. RESULTS: We identified a 14 gene expression signature by comparative analysis of gene expression. Expression of these genes strongly differed between single station and multilevel N2 NSCLC. Four genes (ADAM28, MUC4, CLDN1, and IGF2) correlated with the results of microarray and real-time RT-PCR analysis for the gene-expression data in samples from 56 NSCLC patients. Immunohistochemical staining for these genes in samples from 130 cases of stage N2 NSCLC demonstrated the expression of IGF2 and CLDN1 was negatively correlated with overall survival of stage N2 NSCLC. CONCLUSIONS: Our results suggest that the expression of CLDN1 and IGF2 indicate a poor prognosis in stage N2 NSCLC. Further, CLDN1 and IGF2 may provide potential targeting opportunities in future therapies.

Osteopontin combined with CD44v6, a novel prognostic biomarker in non-small cell lung cancer undergoing curative resection.

BACKGROUND: Osteopontin (OPN) is identified as one of the leading genes that promote the metastasis of malignant tumor through binding to CD44v6 and integrin. The purpose of the current study was to assess the prognostic significance of OPN and CD44v6 in patients with non-small cell lung cancer (NSCLC). METHODS: Tissue microarray was used to detect the expression of OPN and CD44v6 in 159 NSCLC patients undergoing complete pulmonary resection in our hospital between 2003 and 2006. The correlations among OPN, CD44v6, and clinicopathologic data were analyzed using χ(2) testing analysis. The prognostic values of OPN and CD44v6 were evaluated by univariate Kaplan-Meier survival analysis and multivariate Cox proportional hazard model analysis. RESULTS: OPN and CD44v6 were both independent predictors for overall survival and disease-free survival. When OPN and CD44v6 were considered together, the predictive range was extended and the sensitivity was improved, especially for those patients with stage I NSCLC. The 6-year overall survival and disease-free survival rates in OPN+ or CD44v6+ patients were 49.1% and 39.6%, respectively, which were significantly lower than those of OPN-/CD44v6- patients (64.4% and 47.7%, respectively), and were higher than those of OPN+/CD44v6+ patients (16.4% and 14.8%, respectively). Stratification into OPN+/CD44v6+, OPN+ or CD44v6+, or OPN-/CD44v6- groups, based on the expression OPN and CD44v6, could efficiently predicted outcomes (p < 0.001) of NSCLC patients. CONCLUSIONS: The combination of OPN and CD44v6 is a valuable independent predictor of tumor recurrence and survival in NSCLC patients.

Osteopontin knockdown suppresses non-small cell lung cancer cell invasion and metastasis.

BACKGROUND: Osteopontin (OPN) was identified as one of the leading genes that promote the metastasis of malignant tumor. However, the mechanism by which OPN mediates metastasis in non-small cell lung cancer (NSCLC) remains unknown. The aim of the study is to investigate the biological significance and the related molecular mechanism of OPN expression in lung cancer cell line. METHODS: Lentiviral-mediated RNA interference was applied to inhibit OPN expression in metastatic human NSCLC cell line (A549). The invasion, proliferation, and metastasis were evaluated OPN-silenced in A549 cells in vitro and in vivo. The related mechanism was further investigated. RESULTS: Interestingly, OPN knockdown significantly suppressed the invasiveness of A549 cells, but had only a minor effect on the cellular migration and proliferation. Moreover, we demonstrated that OPN knockdown significantly reduced the levels of matrix metalloproteinase (MMP)-2 and urokinase plasminogen activator (uPA), and led to an obvious inhibition of both in vitro invasion and in vivo lung metastasis of A549 cells (P < 0.001). CONCLUSIONS: Our data demonstrate that OPN contributes to A549 cell metastasis by stimulating cell invasion, independent of cellular migration and proliferation. OPN could be a new treatment target of NSCLC.