An in vitro study to explore the role of prolylcarboxypeptidase in non-small cell lung cancer

Prolylcarboxypeptidase (PRCP) belongs to the S28 family of proteases, which is also a dipeptidyl peptidase. In this study, we demonstrate the expression pattern of PRCP in Non-small cell lung cancer (NSCLC). We found that the repression of PRCP expression by small interfering RNA successfully inhibited cell proliferation, migration, and invasion. Further, we explored the involvement of PRCP in the regulation of epithelial-mesenchymal transition (EMT). The epithelial marker E-cadherin was significantly increased, meanwhile mesenchymal markers MUC1, vimentin, and SNAIL were markedly decreased in PRCP knockdown cells. Moreover, the downregulation of PRCP in the NSCLC cells induced the expression of apoptosis-related proteins in vitro. We performed RT-PCR in 30 pairs of clinical NSCLC tissues and adjacent non-cancerous tissues, which revealed significantly higher PRCP expression levels in cancer tissues than in adjacent non-cancerous tissues. Collectively the results from our study suggest a possible cancer promotion role of PRCP in NSCLC.     

pⅢA/N2期非小细胞肺癌患者外科治疗的预后分析

Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2nodal involvement. Methods: A retrospective analysis of disease free survival and 5-year survival for NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy were performed. Between January 1998 and May 2004, 133 patients were enrolled. Several factors such as age, sex, skip metastasis, number of N2 lymph node stations, type of resection, histology, adjuvant therapy etc., were recorded and analyzed. SPSS 16.0 software was used. Results: Overall 5-year survival for 133 patients was 32.33%, 5-year survival for single N2 station and multiple N2 stations sub-groups were 39.62% and 27.50% respectively, and 5-year survival for cN0-1 and cN2 sub-groups were 37.78% and 20.93% respectively.COX regression analysis revealed that number of N2 station (P= 0.013, OR: 0.490, 95% Cl: 0.427-0.781) and cN status (P =0.009, OR: 0.607, 95% Cl: 0.372-0.992) were two favorable prognostic factors of survival. Conclusion: Number of N2 station and cN status were two favorable prognostic factors of survival. In restrict enrolled circumstances, after combined therapy made up of surgery and postoperative adjuvant therapy have been performed, satisfied survival could be achieved.     

Smac在非小细胞肺癌表达的临床意义

Objective:The aim of our study was to investigate the clinical significance of Smac (second mitochondria-derived activator of caspase) expression on non-small cell lung cancer (NSCLC). Methods:The expression of Smac was evaluated on RNA and protein level in tumor tissues. The expression of Smac mRNA was examined by RT-PCR in 59 samples of tumor tissues and matched normal lung tissues. The expression of Smac protein was examined by IHC in 213 cancer tissues. Results:The positive rate of Smac mRNA was found in 59.3% of cancer tissues, but only in 30.5% of matched normal tissues (P < 0.05). The positive rate of Smac protein was 76.5%. The expression of Smac in stage II disease was significantly higher than that in stage I disease (P = 0.001). The survival of patients with Smac overexpression was significantly shorter than those who were negative. Conclusion:Smac might be involved in the progression of NSCLC, the biologic significance of Smac in primary lung cancer needs further study.     

EGFR Mutations in Surgically Resected Fresh Specimens from 697 Consecutive Chinese Patients with Non-Small Cell Lung Cancer and Their Relationships with Clinical Features

We aimed to reveal the true status of epidermal growth factor receptor (EGFR) mutations in Chinese patients with non-small cell lung cancer (NSCLC) after lung resections. EGFR mutations of surgically resected fresh tumor samples from 697 Chinese NSCLC patients were analyzed by Amplification Refractory Mutation System (ARMS). Correlations between EGFR mutation hotspots and clinical features were also explored. Of the 697 NSCLC patients, 235 (33.7%) patients had tyrosine kinase inhibitor (TKIs) sensitive EGFR mutations in 41 (14.5%) of the 282 squamous carcinomas, 155 (52.9%) of the 293 adenocarcinomas, 34 (39.5%) of the 86 adenosquamous carcinomas, one (9.1%) of the 11 large-cell carcinomas, 2 (11.1%) of the 18 sarcomatoid carcinomas, and 2 (28.6%) of the 7 mucoepidermoid carcinomas. TKIs sensitive EGFR mutations were more frequently found in female patients (p < 0.001), non-smokers (p = 0.047) and adenocarcinomas (p < 0.001). The rates of exon 19 deletion mutation (19-del), exon 21 L858R point mutation (L858R), exon 21 L861Q point mutation (L861Q), exon 18 G719X point mutations (G719X, including G719C, G719S, G719A) were 43.4%, 48.1%, 1.7% and 6.8%, respectively. Exon 20 T790M point mutation (T790M) was detected in 3 squamous carcinomas and 3 adenocarcinomas and exon 20 insertion mutation (20-ins) was detected in 2 patients with adenocarcinoma. Our results show the rates of EGFR mutations are higher in all types of NSCLC in Chinese patients. 19-del and L858R are two of the more frequent mutations. EGFR mutation detection should be performed as a routine postoperative examination in Chinese NSCLC patients.     

Network Analysis of Gut Microbiome and Metabolome to Discover Microbiota-Linked Biomarkers in Patients Affected by Non-Small Cell Lung Cancer

Several studies in recent times have linked gut microbiome (GM) diversity to the pathogenesis of cancer and its role in disease progression through immune response, inflammation and metabolism modulation. This study focused on the use of network analysis and weighted gene co-expression network analysis (WGCNA) to identify the biological interaction between the gut ecosystem and its metabolites that could impact the immunotherapy response in non-small cell lung cancer (NSCLC) patients undergoing second-line treatment with anti-PD1. Metabolomic data were merged with operational taxonomic units (OTUs) from 16S RNA-targeted metagenomics and classified by chemometric models. The traits considered for the analyses were: (i) condition: disease or control (CTRLs), and (ii) treatment: responder (R) or non-responder (NR). Network analysis indicated that indole and its derivatives, aldehydes and alcohols could play a signaling role in GM functionality. WGCNA generated, instead, strong correlations between short-chain fatty acids (SCFAs) and a healthy GM. Furthermore, commensal bacteria such as Akkermansia muciniphila, Rikenellaceae, Bacteroides, Peptostreptococcaceae, Mogibacteriaceae and Clostridiaceae were found to be more abundant in CTRLs than in NSCLC patients. Our preliminary study demonstrates that the discovery of microbiota-linked biomarkers could provide an indication on the road towards personalized management of NSCLC patients.     

A549/DDP derived exosomes can affect cisplatin chemosensitivity via transporting CXCR4 to A549 cells

The resistance of cancer cells to the anti-cancer drugs is the most important reason that affecting the efficacy of the non-small cell lung cancer (NSCLC) chemotherapy; thus, to explore the underlying mechanism of drug resistance of NSCLC medications is urgently needed for improving the therapeutic efficacy of current anti-NSCLC chemotherapies. The aim of the present study is to explore the roles of exosomes in the chemosensitivity of A549 cells and the related mechanism. A549 cells and cisplatin resistant cell line A549/DDP derived exosomes were isolated, and the expressions of CXCR4 were compared. Then, after cisplatin treatment, A549 cells were treated with exosomes, and the proliferation, apoptosis, migration, and invasion of the cells were examined. Finally, the tumorigenic effect of A549/DDP derived exosomes were also evaluated by cisplatin treated xenograft tumor mice models in vivo. We found that A549/DDP derived exosomes increased the proliferation, migration, and invasion, and inhibited the apoptosis and cisplatin sensitivity of A549 cells. CXCR4 was also significantly increased in cells treated with A549/DDP derived exosomes. Furthermore, A549/DDP derived exosomes may also decrease the chemosensitivity of NSCLC cells to cisplatin in vivo. Our data suggested that A549/DDP derived exosomes can affect the chemosensitivity of A549 cells to cisplatin, possibly by transporting CXCR4 to A549 cells. Our data may provide novel evidence for the investigation of drug resistance of NSCLC.     

Kynurenine/Tryptophan Ratio as a Potential Blood-Based Biomarker in Non-Small Cell Lung Cancer

The enzyme indoleamine 2,3-dioxygenase 1 (IDO1) degrade tryptophan (Trp) into kynurenine (Kyn) at the initial step of an enzymatic pathway affecting T cell proliferation. IDO1 is highly expressed in various cancer types and associated with poor prognosis. Nevertheless, the serum Kyn/Trp concentration ratio has been suggested as a marker of cancer-associated immune suppression. We measured Kyn and Trp in blood samples of a wide cohort of non-small-cell lung cancer (NSCLC) patients, before they underwent surgery, and analyzed possible correlations of the Kyn/Trp ratio with either IDO1 expression or clinical–pathological parameters. Low Kyn/Trp significantly correlated with low IDO1 expression and never-smoker patients; while high Kyn/Trp was significantly associated with older (≥68 years) patients, advanced tumor stage, and squamous cell carcinoma (Sqcc), rather than the adenocarcinoma (Adc) histotype. Moreover, high Kyn/Trp was associated, among the Adc group, with higher tumor stages (II and III), and, among the Sqcc group, with a high density of tumor-infiltrating lymphocytes. A trend correlating the high Kyn/Trp ratio with the probability of recurrences from NSCLC was also found. In conclusion, high serum Kyn/Trp ratio, associated with clinical and histopathological parameters, may serve as a serum biomarker to optimize risk stratification and therapy of NSCLC patients.     

USP22 Promotes NSCLC Tumorigenesis via MDMX Up-Regulation and Subsequent p53 Inhibition

Increasing evidence suggests that ubiquitin-specific protease 22 (USP22) has great clinicopathologic significance in oncology. In this study, we investigated the role of USP22 in human NSCLC tumorigenesis along with the underlying mechanisms of action. First, we determined the expression of USP22 in human NSCLC, as well as normal tissues and cell lines. We then studied the effects of USP22 silencing by shRNA on NSCLC cell growth in vitro and tumorigenesis in vivo, along with the effect on the p53 pathway. We found that USP22 is overexpressed in human NSCLC tissues and cell lines. USP22 silencing by shRNA inhibits proliferation, induces apoptosis and arrests cells at the G0/G1 phases in NSCLC cells and curbs human NSCLC tumor growth in a mouse xenograft model. Additionally, USP22 silencing downregulates MDMX protein expression and activates the p53 pathway. Our co-immunoprecipitation analysis shows that USP22 interacts with MDMX in NSCLC cells. Furthermore, MDMX silencing leads to growth arrest and apoptosis in NSCLC cells, and over-expression of MDMX reverses the USP22 silencing-induced effects. Taken together, our results suggest that USP22 promotes NSCLC tumorigenesis in vitro and in vivo through MDMX upregulation and subsequent p53 inhibition. USP22 may represent a novel target for NSCLC treatment.