Preliminary Evidence on the Diagnostic and Molecular Role of Circulating Soluble EGFR in Non-Small Cell Lung Cancer

Therapeutic application of extracellular vesicular EGFR isoform D as a co-drug to target squamous cell cancers with tyrosine kinase inhibitors

Targeting wild-type epidermal growth factor receptor (EGFR) using tyrosine kinase inhibitors (TKIs) never achieved its purported success in cancers such as head and neck squamous cell carcinoma, which are largely EGFR-dependent. We had previously shown that exceptional responders to TKIs have a genetic aberration that results in overexpression of an EGFR splice variant, isoform D (IsoD). IsoD lacks an integral transmembrane and kinase domain and is secreted in extracellular vesicles (EVs) in TKI-sensitive patient-derived cultures. Remarkably, the exquisite sensitivity to TKIs could be transferred to TKI-resistant tumor cells, and IsoD protein in the EV is necessary and sufficient to transfer the phenotype in vitro and in vivo across multiple models and drugs. This drug response requires an intact endocytic mechanism, binding to full-length EGFR, and signaling through Src-phosphorylation within the endosomal compartment. We propose a therapeutic strategy using EVs containing EGFR IsoD as a co-drug to expand the use of TKI therapy to EGFR-driven cancers.

Cytokine Profile in Lung Cancer Patients: Anti-Tumor and Oncogenic Cytokines

Lung cancer is currently the second leading cause of cancer death worldwide. In recent years, checkpoint inhibitor immunotherapy (ICI) has emerged as a new treatment. A better understanding of the tumor microenvironment (TMJ) or the immune system surrounding the tumor is needed. Cytokines are small proteins that carry messages between cells and are known to play an important role in the body's response to inflammation and infection. Cytokines are important for immunity in lung cancer. They promote tumor growth (oncogenic cytokines) or inhibit tumor growth (anti-tumour cytokines) by controlling signaling pathways for growth, proliferation, metastasis, and apoptosis. The immune system relies heavily on cytokines. They can also be produced in the laboratory for therapeutic use. Cytokine therapy helps the immune system to stop the growth or kill cancer cells. Interleukins and interferons are the two types of cytokines used to treat cancer. This article begins by addressing the role of the TMJ and its components in lung cancer. This review also highlights the functions of various cytokines such as interleukins (IL), transforming growth factor (TGF), and tumor necrosis factor (TNF).

Relationship Between Cetuximab Target-Mediated Pharmacokinetics and Progression-Free Survival in Metastatic Colorectal Cancer Patients

BACKGROUND AND OBJECTIVE

Cetuximab, an anti-epidermal growth factor receptor (EGFR) monoclonal immunoglobulin (Ig)G1 antibody, has been approved for the treatment of metastatic colorectal cancer (mCRC). The influence of target-antigen on cetuximab pharmacokinetics has never been investigated using target-mediated drug disposition (TMDD) modelling. This study aimed to investigate the relationship between cetuximab concentrations, target kinetics and progression-free survival (PFS).

METHODS

In this ancillary study (NCT00559741), 91 patients with mCRC treated with cetuximab were assessed. Influence of target levels on cetuximab pharmacokinetics was described using TMDD modelling. The relationship between cetuximab concentrations, target kinetics and time-to-progression (TTP) was described using a joint pharmacokinetic-TTP model, where unbound target levels were assumed to influence hazard of progression by an Emax model. Mitigation strategies of concentration-response relationship, i.e., time-varying endogenous clearance and mutual influences of clearance and time-to-progression were investigated.

RESULTS

Cetuximab concentration-time data were satisfactorily described using the TMDD model with quasi-steady-state approximation and time-varying endogenous clearance. Estimated target parameters were baseline target levels (R0 = 43 nM), and complex elimination rate constant (kint = 0.95 day-1). Estimated time-varying clearance parameters were time-invariant component of CL (CL0= 0.38 L/day-1), time-variant component of CL (CL1= 0.058 L/day-1) and first-order rate of CL1 decreasing over time (kdes = 0.049 day-1). Part of concentration-TTP was TTP-driven, where clearance and TTP were inversely correlated. In addition, increased target occupancy was associated with increased TTP.

CONCLUSION

This is the first study describing the complex relationship between cetuximab target-mediated pharmacokinetics and PFS in mCRC patients using a joint PK-time-to-progression model. Further studies are needed to provide a more in-depth description of this relationship.

Opportunities and challenges of neoadjuvant targeted therapy in nonsmall cell lung cancer

PURPOSE OF REVIEW

The aim of this study is to summarize the completed and ongoing clinical trials of neoadjuvant targeted therapy, discuss tolerability and efficacy, and explain the role of neoadjuvant targeted therapy in patients with resectable nonsmall cell lung cancer (NSCLC). At the same time, the existing challenges are presented, including assessment methods, biomarkers, surrogate endpoints and so on. We also put forward our views on possible ways to make improvements and establish neoadjuvant therapy a standard treatment in resectable NSCLC.

RECENT FINDINGS

The mortality of lung cancer has decreased in the last 10 years, which can partly be attributed to advancement of targeted therapy. Targeted therapy has become the first-line treatment for patients with advanced mutation gene positive NSCLC, achieving the effect of prolonging overall survival (OS). Compared with chemotherapy, targeted therapy is associated with good tolerability and high response rate. Neoadjuvant targeted therapy has emerged in recent years and attracted attention of researchers. Early findings proved that neoadjuvant targeted therapy alone can improve patients' disease-free survival (DFS) and the efficacy of combining with other forms of neoadjuvant therapy is also being explored by researchers.

SUMMARY

Neoadjuvant targeted therapy is playing an important role in NSCLC and worth more in-depth research.

Exploration of the Immune-Related Long Noncoding RNA Prognostic Signature and Inflammatory Microenvironment for Cervical Cancer

Purpose: Our research developed immune-related long noncoding RNAs (lncRNAs) for risk stratification in cervical cancer (CC) and explored factors of prognosis, inflammatory microenvironment infiltrates, and chemotherapeutic therapies. Methods: The RNA-seq data and clinical information of CC were collected from the TCGA TARGET GTEx database and the TCGA database. lncRNAs and immune-related signatures were obtained from the GENCODE database and the ImPort database, respectively. We screened out immune-related lncRNA signatures through univariate Cox, LASSO, and multivariate Cox regression methods. We established an immune-related risk model of hub immune-related lncRNAs to evaluate whether the risk score was an independent prognostic predictor. The xCell and CIBERSORTx algorithms were employed to appraise the value of risk scores which are in competition with tumor-infiltrating immune cell abundances. The estimation of tumor immunotherapy response through the TIDE algorithm and prediction of innovative recommended medications on the target to immune-related risk model were also performed on the basis of the IC50 predictor. Results: We successfully established six immune-related lncRNAs (AC006126.4, EGFR-AS1, RP4-647J21.1, LINC00925, EMX2OS, and BZRAP1-AS1) to carry out prognostic prediction of CC. The immune-related risk model was constructed in which we observed that high-risk groups were strongly linked with poor survival outcomes. Risk scores varied with clinicopathological parameters and the tumor stage and were an independent hazard factor that affect prognosis of CC. The xCell algorithm revealed that hub immune-related signatures were relevant to immune cells, especially mast cells, DCs, megakaryocytes, memory B cells, NK cells, and Th1 cells. The CIBERSORTx algorithm revealed an inflammatory microenvironment where naive B cells (p < 0.01), activated dendritic cells (p < 0.05), activated mast cells (p < 0.0001), CD8⁺ T cells (p < 0.001), and regulatory T cells (p < 0.01) were significantly lower in the high-risk group, while macrophages M0 (p < 0.001), macrophages M2 (p < 0.05), resting mast cells (p < 0.0001), and neutrophils (p < 0.01) were highly conferred. The result of TIDE indicated that the number of immunotherapy responders in the low-risk group (124/137) increased significantly (p = 0.00000022) compared to the high-risk group (94/137), suggesting that the immunotherapy response of CC patients was completely negatively correlated with the risk scores. Last, we compared differential IC50 predictive values in high- and low-risk groups, and 12 compounds were identified as future treatments for CC patients. Conclusion: In this study, six immune-related lncRNAs were suggested to predict the outcome of CC, which is beneficial to the formulation of immunotherapy.

Multiomic study of skin, peripheral blood, and serum: is serum proteome a reflection of disease process at the end-organ level in systemic sclerosis?

BACKGROUND

Serum proteins can be readily assessed during routine clinical care. However, it is unclear to what extent serum proteins reflect the molecular dysregulations of peripheral blood cells (PBCs) or affected end-organs in systemic sclerosis (SSc). We conducted a multiomic comparative analysis of SSc serum profile, PBC, and skin gene expression in concurrently collected samples.

METHODS

Global gene expression profiling was carried out in skin and PBC samples obtained from 49 SSc patients enrolled in the GENISOS observational cohort and 25 unaffected controls. Levels of 911 proteins were determined by Olink Proximity Extension Assay in concurrently collected serum samples.

RESULTS

Both SSc PBC and skin transcriptomes showed a prominent type I interferon signature. The examination of SSc serum profile revealed an upregulation of proteins involved in pro-fibrotic homing and extravasation, as well as extracellular matrix components/modulators. Notably, several soluble receptor proteins such as EGFR, ERBB2, ERBB3, VEGFR2, TGFBR3, and PDGF-Rα were downregulated. Thirty-nine proteins correlated with severity of SSc skin disease. The differential expression of serum protein in SSc vs. control comparison significantly correlated with the differential expression of corresponding transcripts in skin but not in PBCs. Moreover, the differentially expressed serum proteins were significantly more connected to the Well-Associated-Proteins in the skin than PBC gene expression dataset. The assessment of the concordance of between-sample similarities revealed that the molecular profile of serum proteins and skin gene expression data were significantly concordant in patients with SSc but not in healthy controls.

CONCLUSIONS

SSc serum protein profile shows an upregulation of profibrotic cytokines and a downregulation of soluble EGF and other key receptors. Our multilevel comparative analysis indicates that the serum protein profile in SSc correlates more closely with molecular dysregulations of skin than PBCs and might serve as a reflection of disease severity at the end-organ level.

Large-Scale Characterization of Systemic Sclerosis Serum Protein Profile: Comparison to Peripheral Blood Cell Transcriptome and Correlations With Skin/Lung Fibrosis

OBJECTIVE

To provide a large-scale assessment of serum protein dysregulation in diffuse cutaneous systemic sclerosis (dcSSc) and to investigate serum protein correlates of SSc fibrotic features.

METHODS

We investigated serum protein profiles of 66 participants with dcSSc at baseline who were enrolled in the Scleroderma: Cyclophosphamide or Transplant Trial and 66 age- and sex-matched healthy control subjects. A panel of 230 proteins, including several cytokines and chemokines, was investigated. Whole blood gene expression profiling in concomitantly collected samples was performed.

RESULTS

Among the participants with dcSSc, the mean disease duration was 2.3 years. All had interstitial lung disease (ILD), and none were being treated with immunosuppressive agents at baseline. Ninety proteins were differentially expressed in participants with dcSSc compared to healthy control subjects. Similar to previous global skin transcript results, hepatic fibrosis, granulocyte and agranulocyte adhesion, and diapedesis were the top overrepresented pathways. Eighteen proteins correlated with the modified Rodnan skin thickness score (MRSS). Soluble epidermal growth factor receptor was significantly down-regulated in dcSSc and showed the strongest negative correlation with the MRSS, being predictive of the score's course over time, whereas α₁ -antichymotrypsin was significantly up-regulated in dcSSc and showed the strongest positive correlation with the MRSS. Furthermore, higher levels of cancer antigen 15-3 correlated with more severe ILD, based on findings of reduced forced vital capacity and higher scores of disease activity on high-resolution computed tomography. Only 14 genes showed significant differential expression in the same direction in serum protein and whole blood RNA gene expression analyses.

CONCLUSION

Diffuse cutaneous SSc has a distinct serum protein profile with prominent dysregulation of proteins related to fibrosis and immune cell adhesion/diapedesis. The differential expression for most serum proteins in SSc is likely to originate outside the peripheral blood cells.

Ascofuranone inhibits epidermal growth factor-induced cell migration by blocking epithelial-mesenchymal transition in lung cancer cells

Ascofuranone, an isoprenoid antibiotic initially purified from a culture broth of Ascochyta viciae, has multiple anticancer effects. However, the impacts of ascofuranone on the epithelial-mesenchymal transition (EMT) and epidermal growth factor (EGF)-induced effects on human lung cancer cell lines have not been previously reported. Here, we show that ascofuranone exerts its anticancer effects by inhibiting the EGF-induced EMT and cell migration in human lung cancer cell lines. Ascofuranone significantly inhibited EGF-induced migration and invasion by lung cancer cells, and suppressed EGF-induced morphologic changes by regulating the expression of EMT-associated proteins. In addition, ascofuranone upregulated E-cadherin, and downregulated fibronectin, vimentin, Slug, Snail, and Twist. Inhibition of ERK/AKT/mTOR promoted EGF-induced E-cadherin downregulation and inhibited EGF-induced vimentin upregulation in response to ascofuranone, implying that inhibition of the EGF-induced EMT by ascofuranone was mediated by the ERK and AKT/mTOR pathways. Inhibition of c-Myc suppressed EGF-induced vimentin upregulation, suggesting the involvement of c-Myc. Collectively, these findings suggest that ascofuranone inhibits tumor growth by blocking the EGF-induced EMT through a regulatory mechanism involving ERK, AKT/mTOR, and c-Myc in lung cancer cells.

Circulating extracellular vesicle-associated TGFβ3 modulates response to cytotoxic therapy in head and neck squamous cell carcinoma

Management of locally advanced head and neck squamous cell carcinoma (HNSCC) requires a multi-prong approach comprising surgery, radiation and/or chemotherapy, yet outcomes are limited. This is largely due to a paucity of biomarkers that can predict response to specific treatment modalities. Here, we evaluated TGFβ3 protein levels in extracellular vesicles (EVs) released by HNSCC cells as a predictor for response to chemoradiation therapy (CRT). To this end, specific EV-fractions were isolated from cell lines or HNSCC patient plasma, and TGFβ3 protein was quantified. In patients treated with CRT, TGFβ3 levels were found to be significantly higher in plasma EV-fractions or non-responders compared with responders. High levels of TGFβ3 levels in Annexin V-EVs were associated with the worst progression-free survival. In vitro experiments demonstrated that TGFβ3 silencing sensitized HNSCC cells to cytotoxic therapies, and this phenotype could be rescued by treatment with exogenous. In addition, specific EV-fractions shed by cisplatin-resistant cells were sufficient to transfer the resistant phenotype to sensitive cells through activation of TGFβ-signaling pathway. Therefore, our data show that TGFβ3 transmitted through EV plays a significant role in response to cytotoxic therapy, which can be exploited as a potential biomarker for CRT response in HNSCC patients treated with curative intent.

Cetuximab pharmacokinetic/pharmacodynamics relationships in advanced head and neck carcinoma patients

AIMS

Cetuximab associated with cisplatin and 5-fluorouracil is used to treat patients with inoperable or metastatic head and neck squamous cell carcinomas (HNSCC) up until disease progression or unacceptable toxicities. To date, no biomarkers of efficacy are available to select patients who will benefit from treatment.

METHODS

An ancillary pharmacokinetics (PK) exploration was performed in the context of a prospective study investigating circulating-tumour cells vs progression-free survival (PFS). Cetuximab plasma concentrations were analysed according to a population PK model. Individual exposure parameters were confronted with soluble epidermal growth factor receptor (sEGFR) concentrations, tumour response and PFS.

RESULTS

PK data (28 patients, 203 observations) were best described by a two-compartment model with linear elimination. Performance status (PS) significantly correlated to both cetuximab clearance and central volume of distribution with both parameters increasing by 33.3% (95% CI 1-65.6) for each 1-point increase of PS compared to PS = 0. Univariate analysis showed that patients with higher trough cetuximab concentrations at Day 7 (C_min,D7 ) had better tumour response (P = 0.03) and longer PFS (P = 0.035). However, multivariate analysis revealed that only PS and tumour size at baseline remained significantly associated with PFS. Levels of sEGFR increased during cetuximab treatment but were not associated with PFS in the multivariate analysis.

CONCLUSIONS

Our study prospectively indicates that PS is likely a confounding factor in the relationship between cetuximab PK and PFS, patients with a poor PS having lower cetuximab plasma exposure and lower PFS.

The importance of programmed death ligand 1 gene expression, epidermal growth factor receptor gene mutations and serum epidermal growth factor receptor levels in Turkish non-small cell lung cancer patients

Background

This study aims to investigate the possible relationships between epidermal growth factor receptor gene mutations, serum epidermal growth factor receptor levels, programmed death ligand gene expression levels and the risks and survivals of resectable nonsmall cell lung cancer patients.

Methods

Deoxyribonucleic acid isolation was performed from peripheral blood samples and tumor tissues. The mutation analysis was performed for epidermal growth factor receptor. Programmed death ligand 1 gene expression levels were examined pathologically and histopathologically following the tissue tracing of 36 non-small cell lung cancer patients (29 males, 7 females; mean age 60.1 years; range, 41 to 79 years) and analyzed using real-time polymerase chain reaction. Epidermal growth factor receptor serum levels were assessed in all patients.

Results

As a result of mutation analyses in 21 patients (28.5% of all adenocarcinoma patients), epidermal growth factor receptor mutation was determined in at least one exon in six patients. In epidermal growth factor receptor mutation detected patients, programmed death ligand 1 gene expression levels were associated with lymph node metastasis (p=0.036). However, epidermal growth factor receptor mutations were not statistically significantly associated according to histopathological examination (p>0.05). Of patients carrying exon 20 (c.2303G>T) mutations, 25% had tumors with perineural invasion. There was a statistically significant association between exon 20 insertions and c.2303G>T and lymphatic invasion (p=0.02), lymph node metastasis and exon 20 insertions (p=0.03). Patients with lower serum epidermal growth factor receptor levels (<400 pg/mL) had better survival time than those with higher serum epidermal growth factor receptor levels (p=0.04).

Conclusion

Programmed death ligand 1 gene expression and epidermal growth factor receptor mutation might have a combined effect on non-small cell lung cancer. Programmed death ligand 1 gene expression in tumor pathology may also be a significant feature for tumor progression and tumorigenesis. Serum epidermal growth factor receptor levels seem to be associated with survival.

Epidermal growth factor receptor expression affects proliferation and apoptosis in non-small cell lung cancer cells via the extracellular signal-regulated kinase/microRNA 200a signaling pathway

The present study assessed the function of epidermal growth factor receptor (EGFR) and its molecular targets in non-small cell lung cancer. The results of the present study demonstrated that EGFR protein and mRNA expression in the normal adjacent tissue specimens was decreased compared with that in the lung cancer tissue samples. Compared with the BEAS-2B normal bronchial epithelial cells, EGFR and phosphorylated (p)-extracellular signal-regulated kinase (ERK) protein expression in the SW-900 and A549 lung cancer cells was increased and microRNA (miR)200a expression in the SW-900 and A549 cells was inhibited compared with the BEAS-2B cells. Downregulating miR200a expression significantly suppressed proliferation and promoted apoptosis and caspase (CASP)3 and CASP9 function in the A549 cells and significantly inhibited EGFR and p-ERK protein expression in the A549 cells, compared with the BEAS-2B cells. The results of the present study indicated that downregulating miR200a significantly suppressed proliferation and promoted apoptosis in A549 cells via the regulation of the EGFR and ERK 1/2 signaling pathways.

Evaluation of serum epidermal growth factor receptor (EGFR) in correlation to circulating tumor cells in patients with metastatic breast cancer

Overexpression of epidermal growth factor receptor in breast cancer is associated with estrogen receptor negativity, higher histological grade and larger tumors. The aim of the present study was to evaluate the clinical significance of serum EGFR (sEGFR) in relation to circulating tumor cells (CTCs) in metastatic breast cancer. 252 patients were enrolled in this prospective multicentre study. Blood was drawn before start of a new line of therapy. sEGFR was determined using a sandwich-type ELISA. CTCs were detected using CellSearch. sEGFR was determined in 48 healthy controls and 252 patients, with no significant differences between the two groups. Clinical-pathological parameters did not correlate with sEGFR, irrespective of the cutoff chosen. Patients with sEGFR levels above the 50^th and 75^th percentile were more likely to present with <5 CTCs per 7.5 ml blood (p = 0.007; p = 0.003). Patients with sEGFR ≥73 ng/ml had significantly longer overall survival than those with sEGFR <73 ng/ml (19.7 vs. 15.2 months; p = 0.007). In the multivariate analysis, presence of ≥5 CTCs, higher grading and higher line of therapy remained independent predictors of shorter OS, while only higher line of therapy and presence of ≥5 CTCs were independent predictors of shorter PFS.

Serum Quantitative Proteomic Analysis Reveals Soluble EGFR To Be a Marker of Insulin Resistance in Male Mice and Humans

To identify circulating factors as candidates involved in type 2 diabetes mellitus (T2DM), we conducted two different quantitative proteomic analyses: (1) db/db mouse sera were compared with db/+ mouse sera obtained at 4, 8, 12, and 24 weeks of age, and (2) db/db mouse sera from animals treated with liraglutide were compared with sera from animals without liraglutide treatment. Twenty proteins were differentially expressed in db/db mouse sera in the first experiment and eight proteins were differentially expressed in db/db mouse sera after liraglutide treatment in the second experiment. Soluble epidermal growth factor receptor (sEGFR) was identified as a common factor, and its protein level was significantly affected in both experiments. An enzyme-linked immunosorbent assay confirmed that the relatively low serum sEGFR levels in db/db mice were restored by liraglutide treatment. The serum sEGFR levels were elevated in diabetic mice with impaired insulin secretion and decreased in high-fat diet-fed mice and ob/ob mice. The serum sEGFR levels increased after the administration of a dual inhibitor of IGF-1/insulin receptor or streptozotocin. In humans with normal glucose tolerance or T2DM, the serum sEGFR levels were correlated with the fasting blood glucose, fasting serum insulin, homeostatic model assessment of insulin resistance, HbA1c, total cholesterol, low-density lipoprotein cholesterol, and triglycerides levels. These findings suggest that sEGFR might be a biomarker for evaluating insulin resistance or a therapeutic target of liraglutide.

Long noncoding RNA EGFR-AS1 mediates epidermal growth factor receptor addiction and modulates treatment response in squamous cell carcinoma

Targeting EGFR is a validated approach in the treatment of squamous-cell cancers (SCCs), although there are no established biomarkers for predicting response. We have identified a synonymous mutation in EGFR, c.2361G>A (encoding p.Gln787Gln), in two patients with head and neck SCC (HNSCC) who were exceptional responders to gefitinib, and we showed in patient-derived cultures that the A/A genotype was associated with greater sensitivity to tyrosine kinase inhibitors (TKIs) as compared to the G/A and G/G genotypes. Remarkably, single-copy G>A nucleotide editing in isogenic models conferred a 70-fold increase in sensitivity due to decreased stability of the EGFR-AS1 long noncoding RNA (lncRNA). In the appropriate context, sensitivity could be recapitulated through EGFR-AS1 knockdown in vitro and in vivo, whereas overexpression was sufficient to induce resistance to TKIs. Reduced EGFR-AS1 levels shifted splicing toward EGFR isoform D, leading to ligand-mediated pathway activation. In co-clinical trials involving patients and patient-derived xenograft (PDX) models, tumor shrinkage was most pronounced in the context of the A/A genotype for EGFR-Q787Q, low expression of EGFR-AS1 and high expression of EGFR isoform D. Our study reveals how a 'silent' mutation influences the levels of a lncRNA, resulting in noncanonical EGFR addiction, and delineates a new predictive biomarker suite for response to EGFR TKIs.

Splice Variants of the RTK Family: Their Role in Tumour Progression and Response to Targeted Therapy

Receptor tyrosine kinases (RTKs) belong to a family of transmembrane receptors that display tyrosine kinase activity and trigger the activation of downstream signalling pathways mainly involved in cell proliferation and survival. RTK amplification or somatic mutations leading to their constitutive activation and oncogenic properties have been reported in various tumour types. Numerous RTK-targeted therapies have been developed to counteract this hyperactivation. Alternative splicing of pre-mRNA has recently emerged as an important contributor to cancer development and tumour maintenance. Interestingly, RTKs are alternatively spliced. However, the biological functions of RTK splice variants, as well as the upstream signals that control their expression in tumours, remain to be understood. More importantly, it remains to be determined whether, and how, these splicing events may affect the response of tumour cells to RTK-targeted therapies, and inversely, whether these therapies may impact these splicing events. In this review, we will discuss the role of alternative splicing of RTKs in tumour progression and response to therapies, with a special focus on two major RTKs that control proliferation, survival, and angiogenesis, namely, epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor-1 (VEGFR1).

Systematic analysis of mRNA expression profiles in NSCLC cell lines to screen metastasis-related genes

Lung cancer is the most prevalent cancer in humans and has the lowest survival outcomes due to its high metastatic potential. The aim of the present study was to screen for metastasis-related genes (MRGs) by investigating the differential expression genes (DEGs) identified by the mRNA expression profiles in SPC-A-1sci (highly metastatic) and SPC-A-1 (parental) cells. DEGs were screened using Genespring software. Gene Ontology and pathway enrichment analyses of these DEGs were performed. Interaction networks between the proteins encoded by the DEGs were identified using the database BioGRID and were visualized by Cytoscape. Modular analysis of the protein-protein interaction network was performed in CFinder. Among these DEGs, the expression levels of 18 genes were examined in SPC-A-1sci and SPC-A-1 cell lines with reverse transcription-quantitative polymerase chain reaction, and 10 of the 18 genes were assessed by western blotting to validate the results of the microarray. Furthermore, the role of metallothionein 1X (MT1X) in non-small cell lung cancer was explored in functional assays and 72 pairs of clinical samples in vitro. Finally, 4,838 DEGs were screened, including 798 upregulated and 4,040 downregulated genes. The significantly enriched functions included gene expression, cytosol and poly-(A) RNA binding, and the most enriched pathway was biosynthesis of antibiotics. Furthermore, MT1X was revealed to promote the migration and invasion ability in SPC-A-1sci and PC-9 lung cancer cell lines. Therefore, MT1X was identified as a candidate MRG through systematic analysis in the present microarray, which was demonstrated to offer potential reference value in screening MRGs.

Soluble Epidermal Growth Factor Receptors (sEGFRs) in Cancer: Biological Aspects and Clinical Relevance

The identification of molecules that can reliably detect the presence of a tumor or predict its behavior is one of the biggest challenges of research in cancer biology. Biological fluids are intriguing mediums, containing many molecules that express the individual health status and, accordingly, may be useful in establishing the potential risk of cancer, defining differential diagnosis and prognosis, predicting the response to treatment, and monitoring the disease progression. The existence of circulating soluble growth factor receptors (sGFRs) deriving from their membrane counterparts has stimulated the interest of researchers to investigate the use of such molecules as potential cancer biomarkers. But what are the origins of circulating sGFRs? Are they naturally occurring molecules or tumor-derived products? Among these, the epidermal growth factor receptor (EGFR) is a cell-surface molecule significantly involved in cancer development and progression; it can be processed into biological active soluble isoforms (sEGFR). We have carried out an extensive review of the currently available literature on the sEGFRs and their mechanisms of regulation and biological function, with the intent to clarify the role of these molecules in cancer (and other pathological conditions) and, on the basis of the retrieved evidences, speculate about their potential use in the clinical setting.