A surveillance method-oriented detection of post-operative spatial-temporal recurrence for non-small cell lung cancer.

BACKGROUND: This study evaluated spatial-temporal recurrence patterns after curative resection for non-small cell lung cancer (NSCLC) to clarify and recommend appropriate post-operative surveillance. METHODS: A total of 2,486 consecutive patients between January 2005 and December 2012 with NSCLC (stage I-IIIA) who underwent definitive surgical resection were retrospectively analyzed. We used a hazard rate curve to evaluate event dynamics. Disease-free survival (DFS) was evaluated by the Kaplan-Meier method. Univariate and multivariate analyses with Cox proportional hazards regression identified risk factors that predicted DFS. RESULTS: The median follow-up was 50.1 months. Recurrences were diagnosed in 852 (34.3%) patients. Four hundred eighty-nine events first occurred in the chest, 177 in the brain, 117 in the bone, and 71 in the abdomen. Of all recurrences, 78.5% occurred in the first 3 years. Univariate and multivariate analyses identified the age at diagnosis (P<0.001), histology (P=0.023), tumor size (P<0.001), pathologic N stage (P<0.001), and grade (P=0.043) as independent risk factors for intra-thoracic recurrences. Histology (P<0.001), tumor size (P<0.001), surgical method (P=0.021), pathologic N stage (P<0.001), and grade (P=0.005) were independent to predict extra-thoracic recurrences. The hazard rate curve displayed an initial surge of time to any treatment failure during 12 months after surgery. Based on sub-group analysis, both intra- and extra-recurrences increased with stage and brain recurrences in stage IIIA occurred earlier than stage II. Hazard rate curve of brain recurrences in squamous cell carcinoma showed a moderate peak during 9-15 months. Hazard rate curves of brain and bone recurrences in adenocarcinoma displayed clear peaks at 9-27 and 15-30 months, respectively. CONCLUSIONS: Intra- and extra-thoracic recurrences correlate with different clinicopathological factors. Brain MRI and bone ECT were recommended for selected patients in particular time to early detect extra-thoracic recurrences.

Capn4 promotes non-small cell lung cancer progression via upregulation of matrix metalloproteinase 2.

The expression of calpain small subunit 1 (Capn4) is correlated with the invasion of several types of tumors. However, the roles of Capn4 in non-small cell lung cancer (NSCLC) remain unclear. In this study, we found that the expression of Capn4 in NSCLC tissues was much higher than that in nontumorous samples. High levels of Capn4 expression were associated with lymph node metastasis and large tumor size in NSCLC patients. The 5-year overall survival rate in the Capn4(high) group was significantly lower than that in the Capn4(low) group. In multivariate analysis, Capn4 was identified as an independent prognostic factor for overall survival. Moreover, in an in vitro analysis, downregulation of Capn4 expression by siRNA suppressed the invasive potential of lung cancer cells. Finally, we demonstrated that Capn4 enhanced the invasion ability of lung cancer cells by upregulating the expression of matrix metalloproteinase 2. Our findings indicated that Capn4 may represent a potential therapeutic target and a novel prognostic marker of NSCLC.

USP7 overexpression predicts a poor prognosis in lung squamous cell carcinoma and large cell carcinoma.

In non-small cell lung cancer (NSCLC), both USP7 expression and p53 gene status were reported to be an indicator of poor prognosis in adenocarcinoma patients; however, its roles and mechanisms in lung squamous cell carcinoma and large cell carcinoma need to be clarified. The USP7 expression was examined in NSCLC tumors (excluding adenocarcinoma), their corresponding non-tumorous tissues, and NSCLC cells. Then, the prognostic role of USP7 was analyzed in 110 NSCLC samples (excluding the adenocarcinoma). Finally, the roles and mechanisms of USP7 in the proliferation, metastasis, and invasion of a NSCLC cell were assessed using a specific vshRNA. The USP7 expression was higher in NSCLC tissues compared to non-tumorous samples, accordingly, the high level of USP7 was detected in NSCLC cell lines compared with HBE cell. After the USP7 downregulation, the H460 cells exhibited decreased metastasis/invasion in vitro and in vivo. The preliminary mechanism study indicated overexpression of USP7 might regulate the p53-MDM2 pathway by inducing the MDM2 de-ubiquitination and subsequent stabilization, which resulted in the upregulation of the Bad phosphorylation. Additionally, we also found that USP7 might induce cell epithelial-mesenchymal transition to enhance the cell invasive ability. Clinically, USP7 overexpression significantly correlated with malignant phenotype. Furthermore, the 5-year overall survival in patients with USP7(low) was higher than that of USP7(high). Multivariate analysis showed USP7 overexpression was an independent prognostic marker for these cancers. USP7 overexpression may regulate the survival and invasive properties of squamous cell carcinoma and large cell carcinoma cells, and may serve as a molecular target.

Genome-wide screening and co-expression network analysis identify recurrence-specific biomarkers of esophageal squamous cell carcinoma.

Tumor recurrence and metastasis after surgery are the leading causes of death in patients with esophageal squamous cell carcinoma (ESCC). Next-generation sequencing techniques have improved our understanding of the genetic alterations underlying tumor initiation and progression. To explore recurrence-specific transcriptional profiles, functional properties, and gene co-expression networks in ESCC, samples from recurrence (n = 4) and nonrecurrence (n = 4) groups were analyzed by RNA sequencing. Patients included in the nonrecurrence group had five or more years of survival without any evidence of recurrence or metastasis, while those included in the recurrence group exhibited early recurrence and metastasis and died within 2 years. We identified 533 significantly differentially expressed protein-coding and noncoding genes. Functional enrichment analysis indicated that ESCC recurrence was related to dysregulated cell-cell adherence, microenvironment homeostasis, information processing, and the immune response. Co-expression networks demonstrated differences in the patterns of gene expression and co-expression between the recurrence and nonrecurrence groups. This study provided important insights into ESCC progression and the differentially expressed genes that may represent potential targets for ESCC diagnosis and therapy.

The overexpression of 14-3-3ζ and Hsp27 promotes non­small cell lung cancer progression.

BACKGROUND: The 14-3-3ζ protein has been identified as a putative oncoprotein in several cancers, including non­small cell lung cancer (NSCLC). However, the mechanisms underlying its functions have not been well defined. METHODS: Proteins that interact with 14-3-3ζ were identified through coimmunoprecipitation and mass spectrometry in NSCLC cells. The interaction of 14-3-3ζ with these molecular partners and their roles in the invasiveness and metastasis of NSCLC cells were assayed through specific disruptions in the 14-3-3ζ signaling network. In addition, the clinical implications of this 14-3-3ζ complex were examined in samples from patients with NSCLC. RESULTS: Among the identified proteins that interacted with 14-3-3ζ, there were 230 proteins in 95-D cells, 181 proteins in 95-C cells, and 203 proteins in A549 cells; and 16 interacting proteins were identified that overlapped between all cell lines. Further studies revealed 14-3-3ζ complexes within the heat shock protein 27 (Hsp27) protein and demonstrated that the interference of Hsp27 or 14-3-3ζ inhibited the invasion and metastasis of NSCLC cells. The invasive and metastatic capabilities of cells with both Hsp27 and 14-3-3ζ interference could be completely restored only by Hsp27 and 14-3-3ζ complementary DNA transfection and not by either agent alone. Clinically, the postoperative 5-year overall survival (OS) in patients who had high expression of both 14-3-3ζ and Hsp27 was significantly lower than the 5-year OS in patients who had low expression of both 14-3-3ζ and Hsp27 (26.5% vs 59.7%, respectively). Multivariate analysis revealed that the combined expression of 14-3-3ζ and Hsp27 was an independent prognostic indicator of OS(P = .036). CONCLUSIONS: The current data suggest that the combined expression of 14-3-3ζ and Hsp27 may be a biomarker for predicting survival in patients with NSCLC, and this combination may have potential as a therapeutic target for NSCLC.

Overexpression of CD88 predicts poor prognosis in non-small-cell lung cancer.

CD88 (C5aR), a G-protein-coupled receptor, is well known as it functions in various inflammatory diseases, however, its role in tumorigenesis remains unclear. In this study we investigated the prognostic value of CD88 in patients with non-small-cell lung cancer (NSCLC) after surgical resection. Five NSCLC cell lines and one normal bronchial epithelial cell line were used to analyze the CD88 expression at the mRNA level. Then, the expression of CD88 and E-cadherin were further examined by immunohistochemistry (IHC) in tissue microarray (TMA) consisting of 208 cases of NSCLSs. Data revealed that CD88 expression was significantly higher in NSCLC cells than that in normal bronchial epithelial cells, and compared with the adjacent non-tumorous lung tissues, the CD88 protein overexpressed in NSCLC tissues. Furthermore, high levels of CD88 were found to be correlated with lymph node metastasis in NSCLC patients (p = 0.012). The 5-year overall survival of patients with CD88(high) was significantly lower than those in the CD88(low) group (p = 0.001), and multivariate analysis revealed that CD88 expression was an independent prognostic factor in patients' overall survival (HR = 1.614, 95% CI 1.082-2.407, p = 0.019). Finally, we confirmed the CD88 expression negatively correlated with E-cadherin expression (p < 0.001). Interference of CD88 expression impaired the migration of lung cancer cells and up-regulated the E-cadherin protein expression. Thus, our results indicate that CD88 is overexpressed in NSCLC. High levels of CD88 are associated with poor prognosis of NSCLC after resection and promote tumor metastasis via down-regulation of E-cadherin. CD88 can be a potential prognostic marker to screen patients for unfavorable prognosis.

Tumor initiating cells in esophageal squamous cell carcinomas express high levels of CD44.

BACKGROUND: Esophageal Squamous Cell Carcinoma (ESCC) is a major subtype of esophageal cancer causing significant morbility and mortality in Asia. Mechanism of initiation and progression of this disease is unclear. Tumor initiating cells (TICs) are the subpopulation of cells which have the ability to self-renew, as well as, to drive initiation and progression of cancer. Increasing evidence has shown that TICs exist in a variety of tumors. However, the identification and characterization of TICs in esophageal carcinoma has remained elusive. METHODOLOGY/PRINCIPAL FINDINGS: to identify TICs in ESCC, ESCC cell lines including two primary cells were used for screening suitable surface marker. Then colony formation assay, drug resistant assay and tumorigenicity assay in immune deficient mice were used to characterize TICs in ESCC. We found that just the CD44 expression correlated with tumorigenicity in ESCC cell lines. And then induced differentiation of ESCC cells by all-trans retinoic acid treatment led to decreased expression of CD44. The FACS isolated cell subpopulations with high CD44 expression showed increased colony formation and drug resistance in vitro, as well as significantly enhanced tumorigenicity in NOD/SICD mice, as compared to the low expressing CD44 ESCC cells. CONCLUSIONS/SIGNIFICANCE: our study has discovered a novel TIC surface marker, CD44, which can be utilized to enrich efficiently the TICs in ESCC. These findings will be useful for further studies of these cells and exploring therapeutic approaches.