Detection of circulating cancer cells in lung cancer patients with a panel of marker genes

Cannot Target What Cannot Be Seen: Molecular Imaging of Cancer Stem Cells

Cancer stem cells are known to play a key role in tumour development, proliferation, and metastases. Their unique properties confer resistance to therapy, often leading to treatment failure. It is believed that research into the identification, targeting, and eradication of these cells can revolutionise oncological treatment. Based on the principle that what cannot be seen, cannot be targeted, a primary step in cancer management is the identification of these cells. The current review aims to encompass the state-of-the-art functional imaging techniques that enable the identification of cancer stem cells via various pathways and mechanisms. The paper presents in vivo molecular techniques that are currently available or await clinical implementation. Challenges and future prospects are highlighted to open new research avenues in cancer stem cell imaging.

Overexpression of FAM83A Is Associated with Poor Prognosis of Lung Adenocarcinoma

Family with sequence similarity 83, member A (FAM83A) plays an essential and fundamental role in the proliferation, progression, and apoptosis of many malignant tumors, including lung cancer. This study aimed to determine the expression pattern of FAM83A in lung adenocarcinoma (LUAD) and its correlation with the prognosis of cancer and the survival of the patients. Bioinformatics analysis, immunohistochemistry, and Western blotting were used to explore and detect the expression of FAM83A in LUAD cells. The mechanism of FAM83A in proliferation and migration was examined. The correlation between FAM83A expression and survival rate was assessed by the Kaplan-Meier and Cox regression. FAM83A expression was elevated in LUAD tissues and was related to shorter overall survival (P < 0.05). A significant increase in FAM83A protein was observed in the LUAD tissue (P < 0.05). Compared with patients with early-stage tumors (stage I-II), those with advanced stage tumors (stage III-IV) had significantly higher FAM83A expression levels (P < 0.05). Downregulation of FAM83A led to a reduction in cell proliferation, a decrease in migration ability, and diminished epithelial-mesenchymal transition (EMT) in the lung cancer cell lines. Overexpression of FAM83A was associated with early lymph node metastasis and poor overall survival among LUAD patients. The findings indicated that FAM83A may play a critical role in promoting the LUAD progression and thus might serve as a novel prognostic marker in LUAD.

Detection of circulating tumor cells: opportunities and challenges

Circulating tumor cells (CTCs) are cells that shed from a primary tumor and travel through the bloodstream. Studying the functional and molecular characteristics of CTCs may provide in-depth knowledge regarding highly lethal tumor diseases. Researchers are working to design devices and develop analytical methods that can capture and detect CTCs in whole blood from cancer patients with improved sensitivity and specificity. Techniques using whole blood samples utilize physical prosperity, immunoaffinity or a combination of the above methods and positive and negative enrichment during separation. Further analysis of CTCs is helpful in cancer monitoring, efficacy evaluation and designing of targeted cancer treatment methods. Although many advances have been achieved in the detection and molecular characterization of CTCs, several challenges still exist that limit the current use of this burgeoning diagnostic approach. In this review, a brief summary of the biological characterization of CTCs is presented. We focus on the current existing CTC detection methods and the potential clinical implications and challenges of CTCs. We also put forward our own views regarding the future development direction of CTCs.

FAM83A Promotes the Proliferative and Invasive Abilities of Cervical Cancer Cells via Epithelial-Mesenchymal Transition and the Wnt Signaling Pathway

The family with sequence similarity 83, member A (FAM83A) gene is associated with the occurrence and development of many malignant tumors. Our aim was to explore the role of FAM83A in cervical cancer. FAM83A was overexpressed or knocked down in cervical cancer cells, and the expressions of FAM83A, key proteins involved in the epithelial-mesenchymal transition (EMT), and Wnt signaling pathway-related proteins were detected by western blot analysis. Cell proliferative and invasive abilities were also examined using cell proliferation, colony formation, and Matrigel invasion assays. Cells were treated with the Wnt pathway inhibitor XAV-939 to determine whether Wnt signaling was necessary for the effect of FAM83A on cervical cancer cells. FAM83A was highly expressed in cervical cancer tissues and was associated with differentiation, TNM stage, lymph node metastasis, and poor prognosis in patients with cervical cancer. Knockdown of FAM83A inhibited the proliferation, colony formation, and invasion of cervical cancer cells. The opposite results were observed in FAM83A-overexpressing cells, and FAM83A overexpression also promoted EMT and Wnt signaling. XAV-939 reversed the activation of Wnt signaling and EMT induced by FAM83A. In conclusion, FAM83A expression was increased in cervical cancers and correlated with poor prognosis of patients. FAM83A overexpression can activate the Wnt signaling pathway, facilitate EMT, and promote the proliferative and invasive abilities of cervical cancer cells.

FAM83A promotes proliferation and metastasis via Wnt/β-catenin signaling in head neck squamous cell carcinoma

This research aimed to investigate the expression and function of FAM83A in the proliferation and metastasis in head and neck squamous cell carcinoma (HNSCC). FAM83A mRNA and protein expressions in HNSCC were detected in primary HNSCC samples and cell lines. The associations between FAM83A expression and clinicopathologic variables were evaluated through tissue microarrays. Besides, FAM83A knockdown and overexpression cell lines were constructed to assess cell growth and metastasis in vitro and the relationship between FAM83A and epithelial-mesenchymal transition (EMT). Furthermore, two models of xenograft tumors in nude mice were used to assess the tumorigenicity and metastasis ability of FAM83A in vivo. In the present study, overexpression of FAM83A in HNSCC samples was significantly associated with tumor size, lymph node status and clinical tumor stages. Mechanically, FAM83A could promote HNSCC cell growth and metastasis by inducing EMT via activating Wnt/β-catenin signaling pathway. Rescue experiment demonstrated the inhibition of β-catenin could counteract the function of FAM83A. Also, the FAM83A knockdown could suppress tumor growth and distant metastasis in the xenograft animal models of HNSCC. In conclusion, this study identifies FAM83A as an oncogene of HNSCC. This study provides new insights into the molecular pathways that contribute to EMT in HNSCC. We revealed a previously unknown FAM83A-Wnt–β-catenin signaling axis involved in the EMT of HNSCC. There may be a potential bi-directional signaling loop between FAM83A and Wnt/β-catenin signaling pathway in HNSCC.

Early Diagnosis and Screening for Lung Cancer

Cancer interception refers to actively blocking the cancer development process by preventing progression of premalignancy to invasive disease. The rate-limiting steps for effective lung cancer interception are the incomplete understanding of the earliest molecular events associated with lung carcinogenesis, the lack of preclinical models of pulmonary premalignancy, and the challenge of developing highly sensitive and specific methods for early detection. Recent advances in cancer interception are facilitated by developments in next-generation sequencing, computational methodologies, as well as the renewed emphasis in precision medicine and immuno-oncology. This review summarizes the current state of knowledge in the areas of molecular abnormalities in lung cancer continuum, preclinical human models of lung cancer pathogenesis, and the advances in early lung cancer diagnostics.

Involvement of MicroRNA-1-FAM83A Axis Dysfunction in the Growth and Motility of Lung Cancer Cells

Lung cancer is the most prevalent types of cancer and the leading cause of cancer-related deaths worldwide. Among all cancers, lung cancer has the highest incidence, accompanied by a high mortality rate at the advanced stage. Favorable prognostic biomarkers can effectively increase the survival rate in lung cancer. Our results revealed FAM83A (Family with sequence similarity 83, member A) overexpression in lung cancer tissues compared with adjacent normal tissues. Furthermore, high FAM83A expression was closely associated with poor lung cancer survival. Here, through siRNA transfection, we effectively inhibited FAM83A expression in the lung cancer cell lines H1355 and A549. FAM83A knockdown significantly suppressed the proliferation, migration, and invasion ability of these cells. Furthermore, FAM83A knockdown could suppress Epidermal growth factor receptor (EGFR)/Mitogen-activated protein kinase (MAPK)/Choline kinase alpha (CHKA) signaling activation in A549 and H1355. By using a bioinformatics approach, we found that FAM83A overexpression in lung cancer may result from miR-1-3p downregulation. In summary, we identified a novel miR-1-FAM83A axis could partially modulate the EGFR/choline phospholipid metabolism signaling pathway, which suppressed lung cancer growth and motility. Our findings provide new insights for the development of lung cancer therapeutics.

FAM83A drives PD-L1 expression via ERK signaling and FAM83A/PD-L1 co-expression correlates with poor prognosis in lung adenocarcinoma

PURPOSE

The purpose of this research was to explore the correlation and prognostic significance of FAM83A and programmed cell death-ligand 1 (PD-L1) protein expression in patients with lung adenocarcinoma (LUAD).

METHODS

A total of 130 LUAD specimens and 50 normal lung tissue specimens were analyzed for both FAM83A and PD-L1 expression by immunohistochemistry (IHC) analysis. The effect of FAM83A on PD-L1 and ERK pathway was evaluated by RT-PCR and western blot in vitro.

RESULTS

Both FAM83A and PD-L1 were upregulated in patients with LUAD and co-expression of them was significantly associated with tumor stage, metastasis and worse survival in LUAD. Multivariate cox regression analysis revealed that co-expression of FAM83A and PD-L1 was an independent prognostic factor impacting survival. Moreover, experiments in vitro showed FAM83A could promote the expression of PD-L1 through the ERK pathway.

CONCLUSION

FAM83A and PD-L1 may be potential therapeutic targets for LUAD. Co-expression of FAM83A and PD-L1 in tumor cells was a credible biomarker predictor for worse survival in resected cases. FAM83A may promote the expression of PD-L1 through ERK signaling pathway, thus causing immune escape of tumor.

FAM83A Is a Prognosis Signature and Potential Oncogene of Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is the most common subtype of nonsmall cell lung cancer, and 5-year survival rate is only 15% in recent years. This study aimed to explore the FAM83A expression and its potential functions in LUAD. Data of LUAD were downloaded from The Cancer Genome Atlas database. Expression level of FAM83A was compared between LUAD samples and adjacent normal samples. The association between FAM83A expression and clinic-pathological parameters was analyzed, as well as copy number variation and methylation status. Kaplan-Meier curve was used to visualize the relationship of FAM83A expression with survival outcomes. Finally, gene set enrichment analysis was used to identify potential signaling pathways in LUAD specimens. FAM83A expression was significantly correlated with four clinical factors in LUAD specimens, age, gender, smoking, and overall survival status (all p < 0.05). High expression level of FAM83A was negatively correlated with methylation level. Moreover, patients in low expression groups exhibited a better prognosis than those in high expressed groups, which was independent of gender (p < 0.001). Histidine metabolism pathway was significantly upregulated in FAM83A-high expressed samples than FAM83A-low expressed samples according to functional enrichment analysis. High expression of FAM83A predicted a poor prognosis in LUAD patients. Our study demonstrated that FAM83A might be a potential biomarker and meaningful therapeutic target in LUAD.

Elevated FAM83A expression predicts poorer clincal outcome in lung adenocarcinoma

BACKGROUND

Family with sequence similarity 83 member A (FAM83A) can promote tumor cell proliferation and facilitate epidermal growth factor tyrosine kinase inhibitor resistance in some malignant tumors, but its role in lung cancer has not been directly explored.

OBJECTIVE

We investigated FAM83A expression in lung adenocarcinoma (LUAD) and its significance in clinicopathologic characteristics and prognosis of the disease.

PATIENTS AND METHODS

We analyzed the mRNA expression of FAM83A in LUAD and normal (or adjacent) lung tissues from Oncomine database firstly. Then, we detected FAM83A protein expression in five paired fresh LUAD and adjacent lung tissue specimens from patients in our hospital by Western blotting. In addtion, FAM83A expression in 86 paraffin-embedded archived LUAD samples was evaluated by Immunohistochemistry, and the correlations between FAM83A expression and clinicopathologic characteristics and prognosis of the patients were analyzed.

RESULTS

Oncomine data analysis manifested that FAM83A mRNA expression was increased in LUAD. Western blotting revealed higher FAM83A expression in fresh LUAD tissues than in the adjacent lung tissues (P= 0.036). Immunohistochemistry analysis on 86 paraffin samples further demonstrated that the LUAD tissue had higher FAM83A expression than adjacent lung tissue (P< 0.001). The correlation analysis revealed that advanced stage tumors (stage III-IV) had higher FAM83A expression than early stage tumors (stage I-II) (P= 0.004). High FAM83A expression was significantly associated with lymphnode involvement and clinical staging (P= 0.008 and 0.008 respectively). Univariate and multivariate Cox regression analysis manifested that FAM83A expression was an independent predictive factor for poor survival. Kaplan-Meier survival curves showed that patients with higher FAM83A expression had shorter overall survival than those with lower FAM83A expressions (P= 0.002).

CONCLUSION

FAM83A is upregulated in advanced LUAD and is related to unfavorible prognosis. FAM83A might be a novel diagnostic and prognositic biomarker for LUAD.

FAM83A Promotes Lung Cancer Progression by Regulating the Wnt and Hippo Signaling Pathways and Indicates Poor Prognosis

FAM83A (family with sequence similarity 83, member A) has been found to be highly expressed in cancers. The purpose of this study was to clarify the role and mechanism of FAM83A in lung cancers. The expression of FAM83A in lung cancer cells was enhanced by gene transfection or knocked down by small interfering RNA interference. The key proteins of the Wnt signaling pathway, the Hippo signaling pathway, and epithelial–mesenchymal transition (EMT) were examined using Western blot. The proliferation and invasion of lung cancer cells were examined using cell proliferation, colony formation, and invasion assays. The expression of FAM83A in lung cancer tissues was significantly increased and was correlated with advanced tumor–node–metastasis (TNM) stage and poor prognosis. Overexpression of FAM83A enhanced the proliferation, colony formation, and invasion of lung cancer cells. Meanwhile, FAM83A overexpression increased the expression of active β-catenin and Wnt target genes and the activity of EMT. Furthermore, in FAM83A-overexpressed cells, the activity of Hippo pathway was downregulated, whereas the expression of yes-associated protein (YAP) and its downstream targets cyclin E and CTGF were upregulated. The inhibitor of the Wnt signaling pathway, XAV-939, reversed the promoting effect of FAM83A on YAP, cyclin E, and CTGF. On knocking down the expression of FAM83A, we obtained the opposite results. However, the inhibitor of GSK3β, CHIR-99021, restored the expression of YAP, cyclin E, and CTGF after FAM83A was knocked down. FAM83A is highly expressed in lung cancers and correlated with advanced TNM stage and poor prognosis. FAM83A promotes the proliferation and invasion of lung cancer cells by regulating the Wnt and Hippo signaling pathways and EMT process.

FAM83A is amplified and promotes tumorigenicity in non-small cell lung cancer via ERK and PI3K/Akt/mTOR pathways

Family with sequence similarity 83A (FAM83A) is a newly-found over-expressed oncogene in several types of cancers and associates with poor prognosis. However, the role that FAM83A may play in the carcinogenesis of non-small cell lung cancer (NSCLC) still needs to be defined. The present study aimed to investigate the function of FAM83A in NSCLC progression and to investigate the possible mechanism. Analysis of Gene Expression Omnibus (GEO) database and rt-PCR showed up-regulated expression of FAM83A in NSCLC. GEO and the Cancer Genome Atlas (TCGA) data analysis revealed that high expression level of FAM83A in NSCLC was associated with poor prognosis. In vitro experiments showed that depleting FAM83A by siRNA/shRNA significantly inhibited cell proliferation and induced cell apoptosis. Cell motility was also retarded after silencing FAM83A, as demonstrated by Transwell assay. FAM83A depletion in A549 cells also inhibited subcutaneous tumor growth and lung metastasis in vivo. Western blotting showed that silencing FAM83A decreased the phosphorylation of ERK and PI3K/Akt/mTOR. On the other hand, overexpressing FAM83A in vitro enhanced cell proliferation and invasiveness, which was repressed by PI3K inhibitor and ERK inhibitor separately. Taken together, our study suggests that FAM83A promotes tumorigenesis of NSCLC at least partly via ERK and PI3K/Akt/mTOR pathways, making it a promising therapeutic target.

Weighted Gene Co-Expression Network Analysis Reveals Six Hub Genes Involved in and Tight Junction Function in Pancreatic Adenocarcinoma and their Potential Use in Prognosis

Background: Pancreatic adenocarcinoma (PAAD) is an aggressive and invasive tumor with poor prognosis. Identifying prognostic biomarkers of PAAD will provide crucial information for developing treatment plans. Methods: In this analysis, a gene-expression dataset, containing RNA-sequencing data recalculated into transcripts per million, was obtained from the UCSC Xena platform. Three thousand nine hundred and seventy six differentially expressed genes were obtained with analysis of variance. Using these data a co-expression network was constructed using weighted gene co-expression network analysis, from which we obtained eight modules. Results: The blue module included 497 genes and demonstrated significant negative correlation with overall survival. Furthermore, pathway analyses demonstrated the involvement of many of these genes in the tight junction pathway, which plays a critical role in PAAD. In addition, we identified six genes in common (i.e., ANXA2 [annexin A2], EPHA2 [erythropoietin-producing hepatocellular class A2], ITGB4 [integrin beta 4], KRT19 [keratin type I cytoskeletal 19], LGALS3 [galectin-3], and S100A14 [S100 calcium binding protein A14]) between the protein-protein interaction and gene co-expression networks that may have critical functions in PAAD. These hub genes were not only highly expressed at the RNA level but also exhibited high expression in the immunohistological data in the Human Protein Atlas Database. Conclusion: Thus, this research clarified the framework of co-expressed gene modules in PAAD and highlighted potential prognostic biomarkers for the clinical diagnosis of PAAD.

A FAM83A Positive Feed-back Loop Drives Survival and Tumorigenicity of Pancreatic Ductal Adenocarcinomas

Pancreatic ductal adenocarcinomas (PDAC) are deadly on account of the delay in diagnosis and dearth of effective treatment options for advanced disease. The insurmountable hurdle of targeting oncogene KRAS, the most prevalent genetic mutation in PDAC, has delayed the availability of targeted therapy for PDAC patients. An alternate approach is to target other tumour-exclusive effector proteins important in RAS signalling. The Family with Sequence Similarity 83 (FAM83) proteins are oncogenic, tumour-exclusive and function similarly to RAS, by driving the activation of PI3K and MAPK signalling. In this study we show that FAM83A expression is significantly elevated in human and murine pancreatic cancers and is essential for the growth and tumorigenesis of pancreatic cancer cells. Elevated FAM83A expression maintains essential MEK/ERK survival signalling, preventing cell death in pancreatic cancer cells. Moreover, we identified a positive feed-forward loop mediated by the MEK/ERK-activated AP-1 transcription factors, JUNB and FOSB, which is responsible for the elevated expression of oncogenic FAM83A. Our data indicates that targeting the MEK/ERK-FAM83A feed-forward loop opens up additional avenues for clinical therapy that bypass targeting of oncogenic KRAS in aggressive pancreatic cancers.

Survival-related risk score of lung adenocarcinoma identified by weight gene co-expression network analysis

The present study aimed to identify the novel biomarkers and underlying molecular mechanisms of lung adenocarcinoma (LAC) to aid in its diagnosis, prognosis, prediction, disease monitoring and emerging therapies. Data from a total of 498 LAC samples were collected from The Cancer Genome Atlas and divided into two sets by stratified randomization based on pathological Tumor-Node-Metastasis stage. The training set was comprised of 348 samples and the validation set was comprised of 150 samples. A total of 123 samples from the training set for patients who completed follow-up were analyzed by weighted gene co-expression network analysis. A module was identified that contained 113 protein-coding genes that were positively associated with overall survival (OS). A least absolute shrinkage and selection operator (LASSO) Cox regression model was constructed and four survival-associated genes (OPN3, GALNT2, FAM83A and KYNU) were retained. Risk score, calculated by the linear combination of each gene expression multiplied by the LASSO coefficient, could successfully discriminate between patients with LAC exhibiting low and high OS time in both sets. The results from the present study indicate that this risk score may contribute to potential diagnostic and therapeutic strategies for LAC management.

FAM83A signaling induces epithelial-mesenchymal transition by the PI3K/AKT/Snail pathway in NSCLC

Family with sequence similarity 83, member A (FAM83A), as a potential tumor promoter, was reported to contribute to the progression of several malignant tumors. However, the significance of FAM83A in invasion and metastasis of non-small cell lung cancer (NSCLC) remains largely unknown. In this study, we found that FAM83A expression was significantly increased in NSCLC tissues. High expression of FAM83A was positively associated with tumor metastasis and poor survival of NSCLC patients. Functional experiments revealed that FAM83A knockdown could suppress NSCLC cell migration and invasion both in vivo and in vitro. While opposite results were observed in FAM83A-transfected cells. Mechanically, we found that FAM83A promoted NSCLC cell migration and invasion by inducing epithelial-mesenchymal transition (EMT) via PI3K/ATK/Snail signaling. Rescue experiment demonstrated that inhibition of either AKT or Snail could partially counteract the promoting effect of FAM83A overexpression in NSCLC metastasis. Taken together, our findings are the first time to demonstrate that increased expression of FAM83A in NSCLC was correlated with EMT and tumor metastasis, which may provide a novel therapeutic target in NSCLC treatment.

The potential of monitoring treatment response in non-small cell lung cancer using circulating tumour cells

Introduction: Circulating tumor cell (CTC) counts represent an attractive strategy for monitoring response to therapy in patients with advanced non-small cell lung cancer (NSCLC). Changes in the CTCs number during the treatment have been proposed as a predictive biomarker of response to both chemotherapy and targeted therapies. Profiling of CTCs might also allow the assessment of the dynamics of predictive biomarkers such as EGFR, ALK, ROS1, and PD-L1, and provide relevant information in patients progressing on treatment with targeted agents including immunotherapeutics. Areas covered: A search of peer-reviewed literature in bibliographic databases was undertaken to discuss studies on CTCs and their predictive role in NSCLC. Expert opinion: To date, some challenges limit the clinical utility of CTCs in monitoring the response to treatment in NSCLC. The standardization of techniques for CTCs isolation and characterization and their validation on larger cohorts of patients might help to translate CTCs analysis in the clinic. However, studies on CTCs can provide information on molecular mechanisms involved in NSCLC progression and in the acquired resistance to treatments.

Overexpression of Family with Sequence Similarity 83, Member A (FAM83A) Predicts Poor Clinical Outcomes in Lung Adenocarcinoma

Background

The aim of this study was to explore the expression levels of family with sequence similarity 83, member A (FAM83A) in lung adenocarcinoma (LUAD) and investigate its clinical prognostic value.

Material/Methods

Bioinformatics mining methods were used to predict the differential expression levels of FAM83A mRNA in LUAD and normal lung tissues based on the TCGA and Oncomine databases. Immunohistochemical staining was performed to demonstrate the FAM83A protein expression levels in 83 cases of LUAD combined with paired normal lung tissues. The correlation between clinicopathologic factors and FAM83A differential expression levels in LUAD was explored by the chi-square test. Kaplan-Meier univariate and Cox multivariate survival analyses were performed to investigate the clinical prognostic value of FAM83A expression in LUAD patients.

Results

Results from TCGA and Oncomine databases revealed that FAM83A mRNA expression level was significantly higher in LUAD than that in normal lung tissues (both P<0.05). Immunohistochemical findings demonstrated that the high positive rate of FAM83A in LUAD was 73.49% (61/83), while that of matched normal lung tissues was only 22.89% (19/83). Moreover, LUAD patients with FAM83A mRNA or high protein levels had dramatically lower OS times than those with FAM83A mRNA or low protein levels (All P<0.05). Lastly, Cox multivariate survival analysis showed that FAM83A differential expression level (low vs. high) was the only independent factor predicting the prognosis of LUAD patients (P=0.001).

Conclusions

FAM83A was overexpressed in LUAD, and FAM83A overexpression could be used as an independent factor of poor prognosis in LUAD patients.

Identification of a putative competitive endogenous RNA network for lung adenocarcinoma using TCGA datasets

The mechanisms underlying the oncogenesis and progression of lung adenocarcinoma (LUAD) are currently unclear. The discovery of competitive endogenous RNA (ceRNA) regulatory networks has provided a new direction for the treatment and prognosis of patients with LUAD. However, the mechanism of action of ceRNA in LUAD remains elusive. In the present study, differentially expressed mRNAs, microRNAs (miRs) and long non-coding RNAs from the cancer genome atlas database were screened. CeRNAs for LUAD were then identified using online prediction software. Among the ceRNAs identified, family with sequence similarity 83 member A (FAM83A), miR-34c-5p, KCNQ1OT1 and FLJ26245 were observed to be significantly associated with the overall survival of patients with LUAD. Of note, FAM83A has potential significance in drug resistance, and may present a candidate biomarker for the prognosis and treatment of patients with LUAD.

The role of liquid biopsy in predicting post-operative recurrence of non-small cell lung cancer

Background

Radical resection is the cornerstone for patients with early stage of non-small cell lung cancer (NSCLC). However, fatal disease recurs in about 30-70% of resected cases. The circulating tumor cells (CTCs) is one of the main causes of recurrence of cancer. Circulating tumor DNA (ctDNA) is also a potential predictive biomarker of recurrence in patients with early stage NSCLC. A meta-analysis was conducted to identify the prognostic value of the CTCs and ctDNA in predicting the disease recurrence after surgery of NSCLC patients.

Methods

Electronic databases were comprehensively searched for eligible studies. A random effects model was used. The primary endpoint was the hazards ratio (HR) for the disease-free survival (DFS) between CTCs/ctDNA positive and negative groups. The relative risks (RR) of one and two-year recurrence rate between CTCs/ctDNA positive and negative groups were also calculated.

Results

A total of 5 studies involving 351 patients were included, in which 3 were studies on CTCs and 2 were ctDNA. Our result revealed that positive peripheral blood CTCs (HR, 3.37; 95% CI: 2.28-4.96; P<0.001) and ctDNA (HR, 8.15; 95% CI: 2.11-31.50; P=0.002) indicated poor prognosis for DFS. One (68% vs. 18.2%; RR 3.28; P<0.001) and two (76% vs. 44%; RR 1.80; P=0.06) years recurrence rate were higher in CTCs positive group compared with the negative group, respectively. The same result was also observed in ctDNA positive versus negative groups of 1 (77.9% vs. 8.3%; RR 9.05; P=0.001) and 2 (85.6% vs. 8.3%; RR 9.63; P<0.001) years recurrence rate.

Conclusions

Both postoperative CTCs and ctDNA are promising predictive biomarkers of early tumor recurrence in NSCLC patients. In addition, detection based on ctDNA seems to be more sensitive than CTCs.

Targeting Pancreatic Cancer Cell Plasticity: The Latest in Therapeutics

Mortality remains alarmingly high for patients diagnosed with pancreatic ductal adenocarcinoma (PDAC), with 93% succumbing to the disease within five years. The vast majority of PDAC cases are driven by activating mutations in the proto-oncogene KRAS, which results in constitutive proliferation and survival signaling. As efforts to target RAS and its downstream effectors continue, parallel research aimed at identifying novel targets is also needed in order to improve therapeutic options and efficacy. Recent studies demonstrate that self-renewing cancer stem cells (CSCs) contribute to metastatic dissemination and therapy failure, the causes of mortality from PDAC. Here, we discuss current challenges in PDAC therapeutics, highlight the contribution of mesenchymal/CSC plasticity to PDAC pathogenesis, and propose that targeting the drivers of plasticity will prove beneficial. Increasingly, intrinsic oncogenic and extrinsic pro-growth/survival signaling emanating from the tumor microenvironment (TME) are being implicated in the de novo generation of CSC and regulation of tumor cell plasticity. An improved understanding of key regulators of PDAC plasticity is providing new potential avenues for targeting the properties associated with CSC (including enhanced invasion and migration, metastatic outgrowth, and resistance to therapy). Finally, we describe the growing field of therapeutics directed at cancer stem cells and cancer cell plasticity in order to improve the lives of patients with PDAC.

Molecular characterization of circulating tumor cells in lung cancer: moving beyond enumeration

Molecular characterization of tumor cells is a key step in the diagnosis and optimal treatment of lung cancer. However, analysis of tumor samples, often corresponding to small biopsies, can be difficult and does not accurately reflect tumor heterogeneity. Recent studies have shown that isolation of circulating tumor cells (CTCs) is feasible in non-small cell lung cancer patients, even at early disease stages. The amount of CTCs corresponds to the metastatic potential of the tumor and to patient prognosis. Moreover, molecular analyses, even at the single-cell level, can be performed on CTCs. This review describes the technologies currently available for detecting and capturing CTCs, the potential for downstream molecular diagnostics, and the clinical applications of CTCs isolated from lung cancer patients as screening, prognostic, and predictive tools. Main limitations of CTCs are also discussed.

Clinical utility of circulating tumor cells in patients with non-small-cell lung cancer

Several different studies have addressed the role of the circulating tumor cells (CTC) in non-small-cell lung cancer (NSCLC). In particular, the potential of CTC analysis in the early diagnosis of NSCLC and in the prediction of the outcome of patients with early and advanced NSCLC have been explored. A major limit of these studies is that they used different techniques for CTC isolation and enumeration, they employed different thresholds to discriminate between high- and low-risk patients, and they enrolled heterogeneous and often small cohort of patients. Nevertheless, the results of many studies are concordant in indicating a correlation between high CTC count and poor prognosis in both early and advanced NSCLC. The reduction of CTC number following treatment might also represent an important indicator of sensitivity to therapy in patients with metastatic disease. Preliminary data also suggest the potential for CTC analysis in the early diagnosis of NSCLC in high-risk individuals. However, these findings need to be confirmed in large prospective trials in order to be transferred to the clinical practice. The molecular profiling of single CTC in NSCLC might provide important information on tumor biology and on the mechanisms involved in tumor dissemination and in acquired resistance to targeted therapies. In this respect, xenografts derived from CTC might represent a valuable tool to investigate these phenomena and to develop novel therapeutic strategies.

Clinicopathological and prognostic significance of circulating tumor cells in patients with lung cancer: a meta-analysis

BACKGROUND

The prognostic significance of circulating tumor cells in patients with lung cancer is controversial. Therefore, we aimed to comprehensively and quantitatively assess the prognostic role of CTCs in patients with lung cancer.

METHODS

The relevant literature was searched using PubMed, the Cochrane database and the China National Knowledge Internet database (up to June 2016). Using Review Manager 5.1.2, a meta-analysis was performed using hazard ratio (HR), odds ratio (OR) and 95% confidence interval (CI) as effect values.

RESULTS

Thirty studies comprising 2,060 patients with lung cancer were analyzed. The pooled HR values showed that circulating tumor cells were significantly correlated with overall survival (HR =2.63, 95% CI [2.04, 3.39]) and progression-free survival (HR =3.74, 95% CI [2.49, 5.61]) in these patients. Further subgroup analyses were conducted and categorized by sampling time, detection method, and histological type; these analyses showed the same trend. The pooled OR values showed that circulating tumor cells were associated with non small cell lung cancer stage(OR = 2.11, 95% CI [1.42, 3.14]), small cell lung cancer stage (OR = 10.91, 95% CI [4.10, 29.06]), distant metastasis (OR =7.06, 95%CI [2.82, 17.66]), lymph node metastasis (OR =2.31, 95% CI [1.19,4.46]), and performance status(OR =0.42, 95%CI [0.22, 0.78]).

CONCLUSION

The detection of circulating tumor cells in the peripheral blood of patients with lung cancer can be indicative of a poor prognosis.

FAM83A is amplified and promotes cancer stem cell-like traits and chemoresistance in pancreatic cancer

Cancer stem cells (CSCs), also known as tumor-initiating cells (TICs), contribute to tumorigenesis, resistance to chemoradiotherapy and recurrence in human cancers, suggesting targeting CSCs may represent a potential therapeutic strategy. In the current study, we found family with sequence similarity 83, member A (FAM83A) is significantly overexpressed and associated with poorer overall survival and disease-free survival in pancreatic cancer. Overexpression of FAM83A markedly promoted, whereas inhibition of FAM83A decreased, CSC-like traits and chemoresistance both in vitro and in an in vivo mouse model of pancreatic cancer. Furthermore, overexpression of FAM83A activated the well-characterized CSC-associated pathways transforming growth factor-β (TGF-β) signaling and Wnt/β-catenin signaling. Importantly, the FAM83A locus was amplified in a number of human cancers and silencing FAM83A in associated cancer cell lines inhibited activation of the WNT/β-catenin and TGF-β signaling pathways and reduced tumorigenicity. Taken together, these results indicate that FAM83A has a vital oncogenic role to promote pancreatic cancer progression and may represent a potential clinical target.

Prognostic Value of Prepro-Gastrin Releasing Peptide in Lung Cancer Patients; NCI-Prospective Study

Background:

Prior series investigated the expression of prepro-gastrin releasing peptide (prepro-GRP) in the peripheral blood of lung cancer patients. Our aim was to assess any prepro-GRP role as a prognostic factor for small cell lung cancer (SCLC) and NSCLC and correlations with clinical presentation and treatment outcome.

Methods:

A prospective study was conducted during the time period from the beginning of January 2012 till the end of January 2014. Prepro-GRP expression was analysed using a nested RT-PCR assay in peripheral blood of 62 untreated lung cancer patients attending the National Cancer Institute (NCI), Cairo University, and 30 age and sex matched healthy volunteers.

Results:

Among the 62 lung cancer cases, there were 24 (38.7%) SCLC, and 38 (61.3%) NSCLC (10 squamous cell carcinomas, 12 adenocarcinomas, 11 large cell carcinomas, 4 undifferentiated carcinomas, and 1 adenosquamous carcinoma). Twenty six patients (41.9%) were prepro-GRP positive. Prepro-GRP expression was higher (58.3%) among SCLC patients compared to NSCLC (squamous cell carcinoma (15.4%), large cell carcinoma (36.4%), and adenocarcinoma (25%)). Mean OS among prepro-GRP negative cases was longer than that among preprogastrin positive cases (17.6 vs 14.9 months). The mean PFS durations among preprogastrin negative versus positive cases were 7.7 vs 4.6 months (p= 0.041). No difference in response to chemotherapy was identified between the groups (p=0.983).

Conclusion:

Prepro-GRP is suggested to be a useful prognostic marker for lung cancer patients, especially with the fast- growing, bad prognostic SCLC type. More studies should aim at detailed understanding of the mechanisms of prepro-GRP action and its use in monitoring the response to treatment in a larger cohort.

The prognostic role of circulating tumor cells in lung cancer

INTRODUCTION

Circulating tumor cells (CTCs) can be isolated from the peripheral blood of cancer patients. Several studies to assess the prognostic and/or predictive role of CTCs have been performed in lung cancer patients.

AREAS COVERED

The state-of-the-art of the role of CTCs in lung cancer patients is reviewed and discussed. A structured search of bibliographic databases for peer-reviewed research literature and of main meetings using a focused review question was undertaken. Expert commentary: Although in the revised studies different technologies, cutoffs, patients' populations and statistical approaches have been used, a high CTCs count as prognostic role in small-cell lung cancer is suggested, whereas additional studies are required to confirm this correlation in non-small-cell lung cancer. A reduction in CTCs count is also likely to be correlated with the lung cancer patients' outcome. Large prospective trials need to confirm the prognostic and/or predictive role of CTCs in lung cancer.

ITPKA Gene Body Methylation Regulates Gene Expression and Serves as an Early Diagnostic Marker in Lung and Other Cancers

INTRODUCTION

Despite recent advances in cancer therapy, the overall 5-year survival rate of patients with lung cancer remains low. The aim of our study was to search for novel markers for early diagnosis in patients with lung cancer.

METHODS

Complementary DNA microarray analysis was performed in primary lung adenocarcinomas and cell lines to search for differentially expressed genes, followed by in vivo and in vitro tumorigenic assays to characterize the oncogenic potential of the candidate genes. Gene body methylation was analyzed by 450K methylation array, bisulfite sequencing, and quantitative methylation-specific polymerase chain reaction assays. In silico analysis of The Cancer Genome Atlas data set was also performed.

RESULTS

Inositol-trisphosphate 3-kinase A gene (ITPKA), a kinase with limited tissue distribution, was identified as a potential oncogene. We showed that ITPKA expression is up-regulated in many forms of cancers, including lung and breast cancers, and that overexpressed ITPKA contributes to tumorigenesis. We also demonstrated that ITPKA expression is regulated by epigenetic DNA methylation of ITPKA gene body through modulation of the binding of SP1 transcription factor to the ITPKA promoter. ITPKA gene body displayed low or absent levels of methylation in most normal tissue but was significantly methylated in malignant tumors. In lung cancer, ITPKA gene body methylation first appeared at the in situ carcinoma stage and progressively increased after invasion.

CONCLUSIONS

ITPKA is a potential oncogene that it is overexpressed in most tumors, and its overexpression promotes tumorigenesis. ITPKA gene body methylation regulates its expression and thus serves as a novel and potential biomarker for early cancer detection.

CPEB4 and IRF4 expression in peripheral mononuclear cells are potential prognostic factors for advanced lung cancer

BACKGROUND/PURPOSE

Lung cancer is a heterogeneous disease with varied outcomes. Molecular markers are eagerly investigated to predict a patient's treatment response or outcome. Previous studies used frozen biopsy tissues to identify crucial genes as prognostic markers. We explored the prognostic value of peripheral blood (PB) molecular signatures in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Peripheral blood mononuclear cell (PBMC) fractions from patients with advanced NSCLC were applied for RNA extraction, cDNA synthesis, and real-time polymerase chain reaction (PCR) for the expression profiling of eight genes: DUSP6, MMD, CPEB4, RNF4, STAT2, NF1, IRF4, and ZNF264. Proportional hazard (PH) models were constructed to evaluate the association of the eight expressing genes and multiple clinical factors [e.g., sex, smoking status, and Charlson comorbidity index (CCI)] with overall survival.

RESULTS

One hundred and forty-one patients with advanced NSCLC were enrolled. They included 109 (77.30%) patients with adenocarcinoma, 12 (8.51%) patients with squamous cell carcinoma, and 20 (14.18%) patients with other pathological lung cancer types. A PH model containing two significant survival-associated genes, CPEB4 and IRF4, could help in predicting the overall survival of patients with advanced stage NSCLC [hazard ratio (HR) = 0.48, p < 0.0001). Adding multiple clinical factors further improved the prediction power of prognosis (HR = 0.33; p < 0.0001).

CONCLUSION

Molecular signatures in PB can stratify the prognosis in patients with advanced NSCLC. Further prospective, interventional clinical trials should be performed to test if gene profiling also predicts resistance to chemotherapy.

RNA-seq analysis of lung adenocarcinomas reveals different gene expression profiles between smoking and nonsmoking patients

Lung adenocarcinoma is caused by the combination of genetic and environmental effects, and smoking plays an important role in the disease development. Exploring the gene expression profile and identifying genes that are shared or vary between smokers and nonsmokers with lung adenocarcinoma will provide insights into the etiology of this complex cancer. We obtained RNA-seq data from paired normal and tumor tissues from 34 nonsmoking and 34 smoking patients with lung adenocarcinoma (GEO: GSE40419). R Bioconductor, edgeR, was adopted to conduct differential gene expression analysis between paired normal and tumor tissues. A generalized linear model was applied to identify genes that were differentially expressed in nonsmoker and smoker patients as well as genes that varied between these two groups. We identified 2273 genes that showed differential expression with FDR < 0.05 and |logFC| >1 in nonsmoker tumor versus normal tissues; 3030 genes in the smoking group; and 1967 genes were common to both groups. Sixty-eight and 70% of the identified genes were downregulated in nonsmoking and smoking groups, respectively. The 20 genes such as SPP1, SPINK1, and FAM83A with largest fold changes in smokers also showed similar large and highly significant fold changes in nonsmokers and vice versa, showing commonalities in expression changes for adenocarcinomas in both smokers and nonsmokers for these genes. We also identified 175 genes that were significantly differently expressed between tumor samples from nonsmoker and smoker patients. Gene expression profile varied substantially between smoker and nonsmoker patients with lung adenocarcinoma. Smoking patients overall showed far more complicated disease mechanism and have more dysregulation in their gene expression profiles. Our study reveals pathogenetic differences in smoking and nonsmoking patients with lung adenocarcinoma from transcriptome analysis. We provided a list of candidate genes for further study for disease detection and treatment in both smoking and nonsmoking patients with lung adenocarcinoma.

NPY1R is a novel peripheral blood marker predictive of metastasis and prognosis in breast cancer patients

The aim of the current study was to evaluate a novel tumor marker, neuropeptide Y receptor Y1 (NPY1R), for the detection of circulating cancer cells and to investigate its clinical significance in breast cancer patients. The Digital Gene Expression Displayer tool of the Cancer Genome Anatomy Project was used to identify the marker gene NPY1R, which is able to detect circulating cancer cells. Nested quantitative polymerase chain reaction was performed to correlate the NPY1R expression levels with the clinicopathological features of 142 breast cancer patients. A follow-up study of 131 of the breast cancer patients was conducted for 38 months. Compared with the 60 normal control individuals, NPY1R was highly expressed in the cancer patients (P<0.01). These high levels of NPY1R expression were positively correlated with the clinical stage and lymph node metastasis status of the disease, as well as with the status of the estrogen and progesterone receptors (P<0.05). Breast cancer patients with circulating cancer cells that expressed NPY1R exhibited shorter tumor-specific survival when compared with those with no NPY1R expression (P<0.01). Additionally, the mortality rate was associated with HER2 expression in the NPY1R positive and negative groups. These results indicate that NPY1R may serve as a useful marker to predict breast cancer metastasis and to evaluate the prognosis of breast cancer patients.

Dynamic EpCAM expression on circulating and disseminating tumor cells: causes and consequences

Formation of metastasis is the most important and lethal step in cancer progression. Circulating and disseminated cancer cells (CTCs/DTCs) in blood and bone marrow are considered as potential metastases-inducing cells. Their detection and characterization has, therefore, become a field of major interest in translational and clinical research in oncology. The main strategy to detect these cells relies thus far on the epithelial characteristics of carcinoma cells and epithelial cell adhesion molecule (EpCAM) represents the most commonly used epithelial marker to capture CTCs/DTCs. Recent data, however, demonstrated a dynamic expression of EpCAM associated with a loss during epithelial-to-mesenchymal transition. The present review summarizes the potential mechanisms and reasons for a dynamic expression of EpCAM.

Apolipoprotein C1 (APOC1) as a novel diagnostic and prognostic biomarker for lung cancer: A marker phase I trial

BACKGROUND

Tumor cells continuously evolve over time in response to host pressures. However, explanations as to how tumor cells are influenced by the inflammatory tumor microenvironment over time are, to date, poorly defined. We hypothesized that prognostic biomarkers could be obtained by exploring the expression of inflammation-associated genes between early and late stage lung cancer tumor samples.

METHODS

Candidate inflammation-associated genes, apolipoprotein C-1 (APOC1), MMP1, KMO)1, CXCL5, CXCL)7, IL-1α, IL-1β, TNF-α and IL-6 were verified by real-time quantitative polymerase chain reaction. Gene expression profiles and immunofluorescence staining of 30 lung cancer tissues were compared.

RESULTS

Expressions of APOC1 and IL-6 mRNA on tumor tissues in late stage disease were significantly higher than in early stage lung cancer samples. Immunofluorescence staining of tumor samples showed that the expression of APOC1 gradually increased from early to late stage in lung cancer patients. The expression levels of IL-6 and APOC1 in tumor samples were positively correlated; however, no prognostic value of APOC1 can be identified in serum samples.

CONCLUSIONS

We found that the level of tumor APOC1 was highly expressed in late stage lung cancer. Further research is warranted to determine the molecular mechanisms underlying the cross talk of APOC1 and IL-6 in tumor progression. An expanded sample size marker phase II study may lead to the discovery of new lung cancer therapeutics targeting APOC1.

Predictive and prognostic value of circulating tumor cell detection in lung cancer: a clinician's perspective

There is increasing evidence for the use of circulating tumor cells (CTCs) as a "liquid biopsy" for early detection of lung cancer recurrence, prognosticating disease and monitoring treatment response. Further, CTC molecular analysis and interrogation of single cells hold significant potential in providing insights into tumor biology and the metastatic process. Ongoing research will likely see the translation of CTCs as a prognostic and predictive biomarker in both small cell, and non-small cell, lung cancer to routine clinical practice.

Clinical utility of circulating tumour cell detection in non-small-cell lung cancer

OPINION STATEMENT

Recent years have witnessed increased interest in the detection of circulating tumour cells (CTCs) for diagnosis, monitoring, and treatment decision making in patients with cancer. Factors that have led to accelerated research in this field include advances in technologies for examination of intact CTCs, personalised medicine with treatment selection according to molecular characteristics, and continued lack of understanding of the biology of treatment resistance and metastasis. CTCs offer promise as a surrogate for tissue where there is insufficient tissue for molecular analysis and where there is a requirement to serially monitor molecular changes in cancer cells through treatment or on progression. In patients with either small cell or non-small cell lung cancer (NSCLC), there is evidence that CTC number is prognostic and that CTCs counted before and after treatment mirror treatment response. In patients with molecularly defined subtypes of NSCLC, CTCs demonstrate the same molecular changes as the cancer cells of the tumour. However, CTCs are not quite ready for "primetime" in the lung cancer clinic. There are still more questions than answers with respect to the optimal technologies for their detection and analysis, their biological significance, and their clinical utility. Despite this the current pace of progress in CTC technology development seems set to make "liquid biopsies" a clinical reality within the next decade. For the everyday clinician and clinical trialist, it will be important to maintain knowledge of the strengths and weaknesses of the technologies and evolving evidence base for CTCs as a routinely used diagnostic tool.

Conserved oncogenic behavior of the FAM83 family regulates MAPK signaling in human cancer

FAM83B (family with sequence similarity 83, member B) was recently identified as a novel oncogene involved in activating CRAF/MAPK signaling and driving epithelial cell transformation. FAM83B is one of eight members of a protein family (FAM83) characterized by a highly conserved domain of unknown function (DUF1669), which is necessary and sufficient to drive transformation. Here, it is demonstrated that additional FAM83 members also exhibit oncogenic properties and have significantly elevated levels of expression in multiple human tumor types using a TissueScan Cancer Survey Panel PCR array and database mining. Furthermore, modeling the observed tumor expression of FAM83A, FAM83C, FAM83D, or FAM83E promoted human mammary epithelial cell (HMEC) transformation, which correlated with the ability of each FAM83 member to bind CRAF (RAF1) and promote CRAF membrane localization. Conversely, ablation of FAM83A or FAM83D from breast cancer cells resulted in diminished MAPK signaling with marked suppression of growth in vitro and tumorigenicity in vivo. Importantly, each FAM83 member was determined to be elevated in at least one of 17 distinct tumor types examined, with FAM83A, FAM83B, and FAM83D most frequently overexpressed in several diverse tissue types. Finally, evidence suggests that elevated expression of FAM83 members is associated with elevated tumor grade and decreased overall survival.

IMPLICATIONS

FAM83 proteins represent a novel family of oncogenes suitable for the development of cancer therapies aimed at suppressing MAPK signaling.

A rapid nested polymerase chain reaction method to detect circulating cancer cells in breast cancer patients using multiple marker genes

The aim of the present study was to develop a simple and rapid method for the detection of circulating cancer cells using multiple tumor markers and to investigate the clinical significance of circulating cancer cells in breast cancer patients. A novel rapid nested polymerase chain reaction (PCR) assay, with high sensitivity and specificity, was evaluated, which was considered to be suitable for clinical application. The rapid nested PCR method was used to detect the circulating cancer cells of 142 breast cancer patients, using a panel of marker genes (FAM83A, NPY1R and KRT19), which were identified by the Digital Gene Expression Displayer Tool of the National Cancer Institute-Cancer Genome Anatomy Project. In total, 79.6% of the 142 breast cancer patient blood samples were found to express at least one tumor marker. In addition, the number of positive markers was found to significantly correlate with the disease stage and presence of distant metastasis. Furthermore, positivity for more than one tumor marker appeared to predict a reduced survival time in breast cancer patients.

Prognostic significance of circulating tumor cells in non-small-cell lung cancer patients: a meta-analysis

Background

The prognostic significance of circulating tumor cells (CTCs) detected in patients with non-small-cell lung cancer (NSCLC) is still inconsistent. We aimed to assess the prognostic relevance of CTCs using a meta-analysis.

Methods

We searched PubMed, Web of Science and EMBASE for relevant studies that assessed the prognostic relevance of CTCs in NSCLC. Statistical analyses were conducted to calculate the summary incidence, odds ratio, relative risks (RRs) and 95% confidence intervals (CIs) using fixed or random-effects models according to the heterogeneity of included studies.

Results

A total of 20 studies, comprising 1576 patients, met the inclusion criteria. In identified studies, CTCs were not correlated with histology (adenocarcinoma vs squamous cell carcinoma) (odds ratio [OR]  =  0.88; 95% confidence interval [CI]: 0.59–1.33; Z = –0.61; P = 0.545). However, pooled analyses showed that CTCs were associated with lymph node metastasis (OR = 2.06; 95% CI: 1.18–3.62; Z = 2.20; P = 0.027) and tumor stage (OR  = 1.95; 95% CI: 1.08–3.54; Z = 2.53; P = 0.011). Moreover, CTCs were significantly associated with shorter overall survival (relative risk [RR]  = 2.19; 95% CI: 1.53–3.12; Z = 4.32; P<0.0001) and progression-free/disease-free survival (RR  = 2.14; 95% CI: 1.36–3.38; Z = 3.28; P<0.0001).

Conclusion

The presence of CTCs indicates a poor prognosis in patients with NSCLC. Further well-designed prospective studies are required to explore the clinical applications of CTCs in lung cancer.

Multiplex PCR-based detection of circulating tumor cells in lung cancer patients using CK19, PTHrP, and LUNX specific primers

INTRODUCTION

The aim of this study was to develop a multiplex polymerase chain reaction (PCR)-based method for detection of circulating tumor cells in peripheral blood of lung cancer (LC) patients.

PATIENTS AND METHODS

Peripheral blood was collected from 71 healthy donors and 125 LC patients at different pathological stages. Samples were analyzed using multiplex PCR, and specific primers for CK19, PTHrP, and LUNX mRNA. The sensitivity of our method was set at 10 LC cells (A549 cells) in 3 mL of peripheral blood of healthy donors using spiking experiments.

RESULTS

The detection rates in LC patients for CK19, PTHrP, and LUNX were 45.6%, 64.8%, and 28%, and in healthy individuals were 7%, 7%, and 5.6%, respectively. Overall, our method produced 77.8% positive detections for at least 1 molecular marker. Twenty-eight (22.2%) were negative for expression of all markers, 39 (31.2%) were positive for expression of 1 marker, 42 (33.6%) were positive for expression of 2 markers, and 17 (13.6%) were positive for expression of all 3 markers. Detection of CK19 mRNA expression positively correlated with LC stage and distant metastases. PTHrP mRNA detection correlated positively with LC stage, presence of bone metastasis, and squamous cell carcinoma, and LUNX mRNA detection correlated with lymph node involvement. Combined detection of 2 or 3 markers was significantly correlated with metastatic disease, and negative detection of all 3 molecular markers was correlated with early stage nonmetastatic disease.

CONCLUSION

Multiple PCR-based detection of CK19, PTHrP, and LUNX mRNA expression provides useful information for disease stage and dissemination in LC patients.

Meta-analysis of circulating tumor cells as a prognostic marker in lung cancer

INTRODUCTION

Recent studies have shown that circulating tumor cells (CTCs) play potential roles as diagnostic and prognostic biomarkers with various cancer types. The aim of this study was to comprehensively and quantitatively summarize the evidence for the use of CTCs to predict the survival outcome of lung cancer patients.

MATERIALS AND METHODS

Relevant literature was identified using Medline and EMBASE. Patients' clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CTC positive rates at different time points (before, during and after treatment) were extracted. A meta-analysis was performed to clarify the prognostic role of CTCs and the correlation between the CTC appearance and clinical characteristics.

RESULTS

A total of 12 articles containing survival outcomes and clinical characteristics and 15 articles containing only clinical characteristics were included for the global meta-analysis. The hazard ratio (HR) for OS predicted by pro-treatment CTCs was 2.61 [1.82, 3.74], while the HR for PFS was 2.37 [1.41, 3.99]. The HR for OS predicted by post-treatment CTCs was 4.19 [2.92, 6.00], while the HR for PFS was 4.97 [3.05, 8.11]. Subgroup analyses were conducted according to histological classification and detection method. Odds ratio (OR) showed the appearance of pro-treatment CTCs correlated with the lymph node status, distant metastasis, and TNM staging, while post-treatment CTCs correlated with TNM staging only.

CONCLUSION

Detection of CTCs in the peripheral blood indicates a poor prognosis in patients with lung cancer.

Analysis of gene expression data from non-small cell lung carcinoma cell lines reveals distinct sub-classes from those identified at the phenotype level

Microarray data from cell lines of Non-Small Cell Lung Carcinoma (NSCLC) can be used to look for differences in gene expression between the cell lines derived from different tumour samples, and to investigate if these differences can be used to cluster the cell lines into distinct groups. Dividing the cell lines into classes can help to improve diagnosis and the development of screens for new drug candidates. The micro-array data is first subjected to quality control analysis and then subsequently normalised using three alternate methods to reduce the chances of differences being artefacts resulting from the normalisation process. The final clustering into sub-classes was carried out in a conservative manner such that sub-classes were consistent across all three normalisation methods. If there is structure in the cell line population it was expected that this would agree with histological classifications, but this was not found to be the case. To check the biological consistency of the sub-classes the set of most strongly differentially expressed genes was be identified for each pair of clusters to check if the genes that most strongly define sub-classes have biological functions consistent with NSCLC.

Quantitative proteomics with siRNA screening identifies novel mechanisms of trastuzumab resistance in HER2 amplified breast cancers

HER2 is a receptor tyrosine kinase that is overexpressed in 20% to 30% of human breast cancers and which affects patient prognosis and survival. Treatment of HER2-positive breast cancer with the monoclonal antibody trastuzumab (Herceptin) has improved patient survival, but the development of trastuzumab resistance is a major medical problem. Many of the known mechanisms of trastuzumab resistance cause changes in protein phosphorylation patterns, and therefore quantitative proteomics was used to examine phosphotyrosine signaling networks in trastuzumab-resistant cells. The model system used in this study was two pairs of trastuzumab-sensitive and -resistant breast cancer cell lines. Using stable isotope labeling, phosphotyrosine immunoprecipitations, and online TiO(2) chromatography utilizing a dual trap configuration, ~1700 proteins were quantified. Comparing quantified proteins between the two cell line pairs showed only a small number of common protein ratio changes, demonstrating heterogeneity in phosphotyrosine signaling networks across different trastuzumab-resistant cancers. Proteins showing significant increases in resistant versus sensitive cells were subjected to a focused siRNA screen to evaluate their functional relevance to trastuzumab resistance. The screen revealed proteins related to the Src kinase pathway, such as CDCP1/Trask, embryonal Fyn substrate, and Paxillin. We also identify several novel proteins that increased trastuzumab sensitivity in resistant cells when targeted by siRNAs, including FAM83A and MAPK1. These proteins may present targets for the development of clinical diagnostics or therapeutic strategies to guide the treatment of HER2+ breast cancer patients who develop trastuzumab resistance.

Genome-scale analysis of DNA methylation in lung adenocarcinoma and integration with mRNA expression

Lung cancer is the leading cause of cancer death worldwide, and adenocarcinoma is its most common histological subtype. Clinical and molecular evidence indicates that lung adenocarcinoma is a heterogeneous disease, which has important implications for treatment. Here we performed genome-scale DNA methylation profiling using the Illumina Infinium HumanMethylation27 platform on 59 matched lung adenocarcinoma/non-tumor lung pairs, with genome-scale verification on an independent set of tissues. We identified 766 genes showing altered DNA methylation between tumors and non-tumor lung. By integrating DNA methylation and mRNA expression data, we identified 164 hypermethylated genes showing concurrent down-regulation, and 57 hypomethylated genes showing increased expression. Integrated pathways analysis indicates that these genes are involved in cell differentiation, epithelial to mesenchymal transition, RAS and WNT signaling pathways, and cell cycle regulation, among others. Comparison of DNA methylation profiles between lung adenocarcinomas of current and never-smokers showed modest differences, identifying only LGALS4 as significantly hypermethylated and down-regulated in smokers. LGALS4, encoding a galactoside-binding protein involved in cell–cell and cell–matrix interactions, was recently shown to be a tumor suppressor in colorectal cancer. Unsupervised analysis of the DNA methylation data identified two tumor subgroups, one of which showed increased DNA methylation and was significantly associated with KRAS mutation and to a lesser extent, with smoking. Our analysis lays the groundwork for further molecular studies of lung adenocarcinoma by identifying novel epigenetically deregulated genes potentially involved in lung adenocarcinoma development/progression, and by describing an epigenetic subgroup of lung adenocarcinoma associated with characteristic molecular alterations.

Circulating CYFRA 21-1 is a Specific Diagnostic and Prognostic Biomarker in Biliary Tract Cancer

BACKGROUND: Biliary tract cancer (BTC) has a poor prognosis, in part related to difficulties in diagnosis. Cytokeratin 19 (CK19) is a constituent of the intermediate filament proteins of epithelial cells. CK19 fragments (CYFRA 21-1) are rarely identified in the blood of healthy individuals. We assessed the utility of CYFRA 21-1 as a diagnostic and prognostic marker of BTC. METHODS: Blood was prospectively collected from patients with benign biliary disease (n = 39), primary sclerosing cholangitis (n = 19), PSC-related cholangiocarcinoma (n = 6) and sporadic BTC (n = 60). CYFRA 21-1 levels were measured in duplicate by ELISA. RESULTS: CYFRA 21-1 (≥ 1.5 ng/mL) had a sensitivity of 56% and specificity of 88%, compared with figures of 79% and 78% for CA 19-9 (≥ 37U/mL). Using a higher cut-off of 3 ng/mL, CYFRA 21-1 had a sensitivity of 30% and specificity of 97%. Combination of CYFRA 21-1 (≥ 1.5 ng/mL) and CA 19-9 (≥ 37 U/mL) resulted in sensitivity and specificity of 45% and 96%. In contrast to CA 19-9, CYFRA 21-1 (≥ 3.0 ng/mL) alone was a strong predictor of prognosis (median survival 2 months vs 10 months, p = 0.001). CONCLUSION: Elevated circulating CYFRA 21-1 is a specific, but less sensitive diagnostic marker than CA 19-9, predicts a poor outcome and may act as a surrogate marker of circulating tumor cells in BTC. Further prospective studies of its utility in assessing operability and response to chemotherapy are needed.

Prognostic relevance of circulating tumor cells in metastatic uveal melanoma

OBJECTIVE

Uveal melanoma primarily metastasizes hematogenously with metastases often confined to the liver. The aim of this study was to investigate the presence of circulating tumor cells (CTC) in patients with metastatic disease as a marker for systemic disease and to determine their prognostic relevance.

METHODS

Blood samples from 68 patients were collected at the time of initial treatment of metastases. mRNA expression of tyrosinase and MelanA/MART1 as a surrogate marker for the presence of CTC was analyzed by real-time RT-PCR and compared with patient characteristics.

RESULTS

CTC were detected in 63% of all patients and in 67% of the 48 patients with only liver metastases. Univariate and multivariate analyses revealed PCR results and serum lactate dehydrogenase as independent prognostic factors for progression-free (hazard ratios 2.2/3.5) and overall survival (hazard ratios 4.0/6.5). Combination of PCR and lactate dehydrogenase divided the patient cohort into 3 groups with distinct prognosis.

CONCLUSION

CTC as evidence for systemic disease can be found in the majority of patients with metastatic uveal melanoma, including patients with visible disease confined to the liver. Detection of CTC-specific mRNA transcripts for tyrosinase and MelanA/MART1 by PCR is a poor prognostic factor for progression-free and overall survival. Characterization of CTC could improve the understanding of their biology.

Circulating tumor cells (CTCs) in lung cancer: current status and future perspectives

Primary lung cancer is the leading cause of cancer-related deaths in most industrialized countries, and it is important to detect and control metastases distant from the lungs for improvement of a patient's prognosis. Circulating tumor cells (CTCs) are tumor cells that are shed from the primary site and circulate in the peripheral blood, and recent studies have shown that CTCs can be useful clinical markers in some solid tumors such as those of breast cancer. In primary lung cancer, the clinical significance of CTCs remains unclear, but some promising results have been recently reported. Here, we reviewed the current status and future perspectives of CTCs in primary lung cancer.

Implications of cancer-associated systemic inflammation for biomarker studies

Highly sensitive molecular technologies provide new capacities for cancer biomarker research, but with sensitivity improvements marker specificity is significantly decreased, and too many false-positive results should disqualify the measurement from clinical use. Hence, of the thousands of potential cancer biomarkers only a few have found their way to clinical application. Differentiating false-positive results from true-positive (cancer-specific) results can indeed be difficult, if validation of a marker is performed against inadequate controls. We present examples of accumulating evidence that not only local but also systemic inflammatory reactions are implicated in cancer development and progression and interfere with the molecular image of cancer disease. We analyze several modern strategies of tumor marker discovery, namely, proteomics, metabonomics, studies on circulating tumor cells and circulating free nucleic acids, or their methylation degree, and provide examples of scarce, methodologically correct biomarker studies as opposed to numerous methodologically flawed biomarker studies, that examine cancer patients' samples against those of healthy, inflammation-free persons and present many inflammation-related biomarker alterations in cancer patients as cancer-specific. Inflammation as a cancer-associated condition should always be considered in cancer biomarker studies, and biomarkers should be validated against their expression in inflammatory conditions.