p53 protein, EGF receptor, and anti-p53 antibodies in serum from patients with occupationally derived lung cancer

Autoantibodies as diagnostic biomarkers for lung cancer: A systematic review

Lung cancer (LC) accounts for the largest number of tumor-related deaths worldwide. As the overall 5-year survival rate of LC is associated with its stages at detection, development of a cost-effective and noninvasive cancer screening method is necessary. We conducted a systematic review to evaluate the diagnostic values of single and panel tumor-associated autoantibodies (TAAbs) in patients with LC. This review included 52 articles with 64 single TAAbs and 19 with 20 panels of TAAbs. Enzyme-linked immunosorbent assays (ELISA) were the most common detection method. The sensitivities of single TAAbs for all stages of LC ranged from 3.1% to 92.9% (mean: 45.2%, median: 37.1%), specificities from 60.6% to 100% (mean: 88.1%, median: 94.9%), and AUCs from 0.416 to 0.990 (mean: 0.764, median: 0.785). The single TAAb with the most significant diagnostic value was the autoantibody against human epididymis secretory protein (HE4) with the maximum sensitivity 91% for NSCLC. The sensitivities of the panel of TAAbs ranged from 30% to 94.8% (mean: 76.7%, median: 82%), specificities from 73% to 100% (mean: 86.8%, median: 89.0%), and AUCs from 0.630 to 0.982 (mean: 0.821, median: 0.820), and the most significant AUC value in a panel (M13 Phage 908, 3148, 1011, 3052, 1000) was 0.982. The single TAAb with the most significant diagnostic calue for early stage LC, was the autoantibody against Wilms tumor protein 1 (WT1) with the maximum sensitivity of 90.3% for NSCLC and its sensitivity and specificity in a panel (T7 Phage 72, 91, 96, 252, 286, 290) were both above 90.0%. Single or TAAbs panels may be useful biomarkers for detecting LC patients at all stages or an early-stage in high-risk populations or health people, but the TAAbs panels showed higher detection performance than single TAAbs. The diagnostic value of the panel of six TAAbs, which is higher than the panel of seven TAAbs, may be used as potential biomarkers for the early detection of LC and can probably be used in combination with low-dose CT in the clinic.

Comparative proteomic analysis in serum of former uranium miners with and without radon induced squamous lung cancer

Summary

Former uranium miners of the Wismut Company, East Germany, have been exposed to ionizing radiation from radon decay products and therefore were at high risk for lung cancer. Since histological types of cancer in the so called Wismut cohort revealed an association of high radon exposure with a higher relative frequency of squamous cell carcinoma (SqCC), we used comparative proteomic analysis to identify differentially expressed proteins in serum exposed uranium miners with SqCC.

Methode

Pooled sera of exposed former uranium miners without lung disease and pooled sera of former uranium miners with SqCC were analysed by 2-D gel electrophoresis. MALDI-TOF-MS was performed from reproducable, significantly, at least 5-fold up-regulated protein spots. Proteins were identified by MASCOT peptide mass fingerprint search. Additionally a receiver operating characteristic curve for CYFRA 21-1 was created.

Results

The protein spots were identified as Keratin 10 (K10), Keratin 1 (K1), complement factor H (CFH) and a haptoglobin (Hpt) fragment. The sensitivity for CYFRA 21-1 reveals 60% at a specifity of 95 and 80% at a specifity of 80%. Plotting the sensitivity against specifity reveals an AUC of 0.88.

Conclusion

In SqCC Keratin 10 and 1 were strongly induced. This was associated with CYFRA 21-1, confirming the cytokeratin fragment as a tumormarker.

Early stages of mesothelioma, screening and biomarkers

The early diagnosis of mesothelioma is notoriously difficult, both from a clinical and pathological perspective. Patients often undergo several medical investigations without definitive diagnosis. The discovery of biomarkers that can be assessed in pleural effusions, histological samples, and serum may assist with the difficult early diagnosis of mesothelioma. In this chapter we focus on those markers that have been examined in the setting of either early diagnosis of mesothelioma in symptomatic individuals or that have been proposed as suitable for screening of asbestos-exposed individuals, with an emphasis on cytology and histology.

Soluble epidermal growth factor receptor (sEGFR) and carcinoembryonic antigen (CEA) concentration in patients with non-small cell lung cancer: correlation with survival after erlotinib and gefitinib treatment

BACKGROUND

In patients with non-small cell lung cancer (NSCLC), a higher response rate can be achieved with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) when selection for therapy is guided by mutation analysis or gene amplification. However, both tests are complex and require tumour tissue. Simple methods to identify responders prior to EGFR-TKI treatment are urgently needed. This study aimed to define the relation between serum sEGFR levels, carcinoembryonic antigen (CEA) and survival in NSCLC patients treated with EGFR-TKIs.

METHODS

Patients with stage III/IV NSCLC treated with gefitinib or erlotinib between July 2002 and December 2005 were reviewed. Levels of serum soluble EGFR (sEGFR) were determined by a sandwich quantitative enzyme-linked immunosorbent assay. A chemiluminescence immunoassay was used for CEA. The relation between sEGFR and survival was investigated.

RESULTS

One hundred and two NSCLC patients, mainly stage IV (80%), were identified. Mean sEGFR at baseline was 55.9 μg/l (range 35.3-74.5 μg/l). The median CEA level was 11.1 μg/l (range <1.0-2938.0 μg/l). Median overall survival was 5.2 months (range 1-52 months). Decreasing log CEA values (HR 1.51, 95% CI 1.11-2.04, multivariate analysis) and increasing sEGFR values (HR 0.96, 95% CI 0.93-0.99, multivariate analysis) were both independently associated with prolonged survival. Higher levels of pre-treatment sEGFR were associated with lower risk of progressive disease within three months (p=0.04).

CONCLUSIONS

Both baseline sEGFR and CEA levels in NSCLC patients receiving EGFR-TKIs showed a significant correlation with survival. To distinguish whether these factors have a predictive or a prognostic value, validation is warranted in an independent patient series containing a control arm without EGFR-TKI treatment.

Tissue and serum EGFR as prognostic factors in malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is an asbestos related aggressive tumor. Asbestos causes genetic modifications and cell signaling events that favor resistance to chemotherapy. A variety of receptor tyrosine kinases have been identified to play a central role in various aspects of tumorigenesis. Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies including lung cancer in which EGFR aberrations not only predict response to EGFR tyrosine kinase inhibitors but also indicate tumor progression. However in MPM, the role of EGFR is less clear. This study was designed to identify serum and tissue EGFR levels in patients with MPM and to evaluate the relationship between serum and tissue EGFR levels and clinicao-pathological prognostic factors and survival.

METHODS

We investigated 71 cases of MPM for EGFR expression in tissue. Serum EGFR was assessed in 40 out of those 71 cases and 20 healthy subjects as a control. Pre-treatment serum EGFR levels were measured using quantitative enzyme-linked immunosorbent assay. Tissue EGFR protein overexpression was assessed by immunohistochemistry and gene amplification was assessed by the chromogen in situ hybridization (CISH) technique. Results were correlated with the clinical-pathological factors of the patients and overall survival (OS).

RESULTS

Out of the 71 patients included in the study, 19 had undergone extrapleural pneumonectomy. As for the rest of the patients, 46 received chemotherapy while 6 had only best supportive care. EGFR immuno-reactivity was detected in 74.6% of the cases, 37 (52.1%) cases were positive for EGFR gene amplification by CISH, 31 of them revealed moderate to high (++, +++) EGFR immuno-reactivity. Elevated serum EGFR >2.5 ng/ml (the median concentration of EGFR in MPM) was reported in 45% of the cases. The overall response rate (RR) for the 46 treated patients who received chemotherapy was 24.1%. After a median follow up of 29 months, the median overall survival (OS) was 10 months. Elevated serum and tissue EGFR is significantly associated with advanced disease stage. However neither EGFR overexpression in tissues nor high serum levels were associated with survival rates.

CONCLUSIONS

EGFR expression is a common feature in MPM patients. High pre-treatment levels of serum EGFR are associated with advanced stage but not with reduced OS. Detailed mutational analysis of EGFR on a larger number of patients is still needed to clarify the exact role of EGFR in MPM patients.

Serum p53 protein and anti-p53 antibodies are associated with increased cancer risk: a case-control study of 569 patients and 879 healthy controls

The aim of this study to determine whether serum p53 protein and antibodies are associated with malignant tumors. A case-control study was conduct in 569 patients with various types of malignant tumors and 879 healthy controls. Serum p53 protein and antibodies were analyzed by enzyme-linked immunosorbent assay (ELISA).The rate of positive p53 protein in patients with various malignant tumors was 4.22% compared with 0.34% in healthy controls (P < 0.001). The rate of anti-p53 antibodies in patients with various malignant tumors was 14.59% compared with 1.02% in healthy controls (P < 0.001). The adjusted odd ratio (OR) for p53 protein was 17.55 (95% CI = 4.98-61.94). The adjusted odd ratio for anti-p53 antibodies was 14.27 (95% CI = 6.75-30.16). The study strongly suggested that serum p53 protein and antibody are associated with increased cancer risk and can be used as early serological markers in the diagnosis of malignancies tumors.

Oncogene and tumor-suppressor gene products as serum biomarkers in occupational-derived lung cancer

Since lung cancer is the most frequent occupational cancer and one of the leading causes of cancer mortality in the world, it is one of the biggest challenges for research. In the literature, there are inconsistent results regarding the utility of the serum biomarkers p53, anti-p53 antibodies, EGF receptor or Ras. Based on the published results, routine use of these biomarkers for detection of occupationally derived lung carcinomas is not currently recommended. In this review, we summarize the literature and discuss the relevance of these oncogene and tumor-suppressor gene products as serum biomarkers in occupational-derived lung cancer.

Alteration of the serum levels of the epidermal growth factor receptor and its ligands in patients with non-small cell lung cancer and head and neck carcinoma

Serum levels of the soluble epidermal growth factor receptor (sEGFR) and its ligands epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and amphiregulin (AR) were measured in healthy donors and patients with non-small cell lung cancer (NSCLC) and head and neck carcinoma (HNC). In NSCLC, we found sEGFR and EGF levels significantly lowered in patients with respect to healthy donors. In HNC patients, significantly diminished levels were found in the case of sEGFR, EGF and also AR. In both malignancies, no significant association was found between the serum levels of the molecules and the patients' gender, age or smoking habit. Only a significant association was found between the decrease of sEGFR and the absence of distant metastasis in NSCLC and the tumour stage in HNC. The most interesting result was that combining sEGFR and EGF, sensitivities of 88% in NSCLC and 100% in HNC were reached without losing specificity (97.8% in both cases). The use of discriminant analysis and logistic regression improved the sensitivity for NSCLC and the specificity for HNC. These data demonstrate a potentially interesting value of the serum levels of sEGFR and EGF, especially when combined, as markers for NSCLC and HNC.

Targeting receptor tyrosine kinase signalling in small cell lung cancer (SCLC): what have we learned so far?

Small cell lung cancer (SCLC) is an aggressive form of lung cancer, which represents 13% of all cases and is strongly associated with cigarette smoking. The survival of SCLC patients is dismal and has not greatly improved in the last 20 years, despite advances in chemotherapy regimens and a better understanding of SCLC biology. The development of resistance to chemotherapy and metastasis are commonly recognized as important causes of poor clinical outcome in SCLC. Targeting receptor tyrosine kinase (RTK) signalling represents an attractive approach to develop new drugs for SCLC, in view of the accumulating data demonstrating that polypeptide growth factors play a key role in driving SCLC cell proliferation, chemoresistance and metastasis. The insulin-like growth factor-I receptor (IGF-IR), c-Kit, vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR) have been identified as potential drug targets in SCLC. Moreover, downstream signalling mediators of RTKs, such as phosphoinositide 3-kinase (PI3K)/Akt and the mammalian target of rapamycin (mTOR) may also represent attractive candidate molecules for anti-cancer therapies in SCLC. Here we will review the available data concerning results with RTK inhibitors in SCLC and the clinical trials undertaken to investigate the potential of these compounds as anti-tumour agents in SCLC.

Tumor markers in detection of lung cancer

The expression of biomarkers by lung cancers is useful in the diagnosis and clinical management of patients with lung cancer. Biomarkers provide insight into histogenesis, interrelationships, and biological behavior of lung tumors. This chapter presents data on lung cancer detection, involving some of the most studied and interesting lung cancer biomarkers to date-CYFRA 21-1, NSE, ProGRP, SCC, CEA, Tumor M2-PK, as well as markers in clinical application such as CRP, LDH, tumor-suppressor genes and oncogenes, CA125, CgA, NCAM, and TPA. Biomarker profiles in combination with fuzzy logic techniques have also been addressed. Serum markers used alone or in combination with other indices might play an important role in monitoring response to therapy in early detection of tumor reactivation in new treatment strategies as well as in secondary prevention.

Serum epidermal growth factor receptor/HER-2 predicts poor survival in patients with metastatic breast cancer

BACKGROUND

Epidermal growth factor receptor (EGFR, HER-1, and erbB1) is overexpressed in primary breast cancer and had been identified as a poor prognostic factor.

METHODS

Pretreatment serum EGFR levels were quantified by using an enzyme-linked immunoadsorbent assay in a Phase III first-line trial of letrozole and tamoxifen and were correlated with patient outcomes.

RESULTS

Serum EGFR levels in a control group of 117 healthy, postmenopausal women measured 64.1 +/- 13.3 ng/mL (mean +/- standard deviation). Using a cutoff EGFR level of 44.1 ng/mL from the control group (5% nonparametric method), 53 of 535 patients (10%) had decreased serum levels of EGFR. Patients with decreased serum EGFR had no significant difference in objective response rate (ORR), clinical benefit rate (CBR), time to progression (TTP), or time to treatment failure (TTF); however, they did have significantly reduced survival compared with patients who had normal serum EGFR levels (median survival, 23.3 months vs. 30.9 months; P = .007). A combined analysis of pretreatment serum EGFR and HER-2 yielded no additional predictive information for ORR, CBR, TTP, or TTF compared to serum HER-2 alone. However, in the current analysis, a subgroup of patients who had decreased serum EGFR and normal serum HER-2 was identified (n = 39 of 535 patients; 7.3%) that had significantly reduced survival compared with patients who had normal serum levels of both EGFR and HER-2 (median survival, 23.5 months vs. 37.1 months; P = .005). In multivariate analysis, a decreased serum EGFR level remained a significant independent prognostic factor for decreased survival (hazards ratio, 1.58; P = .007).

CONCLUSIONS

In patients who had metastatic breast cancer, decreased serum EGFR/normal serum HER-2 predicted shorter survival compared with patients who had normal levels of serum EGFR/HER-2. This patient subgroup deserves further study to assess their response to and selection for anti-EGFR-directed therapies.

Concentration of hydroxyproline in blood: a biological marker in occupational exposure to asbestos and its relationship with Pi*Z and Pi*S polymorphism in the alpha-1 antitrypsin gene

BACKGROUND

Hydroxyproline (OHP) is one of the most abundant amino acids in collagen and, in general, it provides a good measure of overall collagen catabolism.

METHODS

Asbestos workers suffering from asbestosis (cases n = 85); asbestos exposed workers without asbestosis (exposed controls, EC, n = 86), and non-exposed population (non-exposed controls, NEC, n = 122) were studied. The concentration of free OHP in whole blood was measured following the Pico-Tag procedure.

RESULTS

Concentration of OHP in blood was significantly different in the three groups studied (P < 0.001), being higher in cases (19.8 +/- 14.7 micromol/L) than in EC (16 +/- 12.4) and NEC (13.5 +/- 6.7). When all individuals were grouped and stratified by the Pi*S and Pi*Z polymorphisms in the alpha-1-antitrypsin gene, the highest OHP levels were detected in the Pi*S homozygotes, one of the asbestosis-at risk-genotypes (Pi*S homozygotes, x = 24.5 +/- 11.7; Pi*S heterozygotes, x = 16.6 +/- 10.0; wild type, wt, x = 15.9 +/- 11.8).

CONCLUSIONS

Blood OHP concentration could be used for monitoring human exposure to asbestos, either as a marker for occupational monitoring or as an additional clinical parameter in diagnostic exploration of asbestosis.

Autoantibodies to protein transport and messenger RNA processing pathways: endosomes, lysosomes, Golgi complex, proteasomes, assemblyosomes, exosomes, and GW bodies

Over 50 years ago the lupus erythematosus (LE) cell phenomenon was described and this was quickly followed by the introduction of the LE cell test and indirect immunofluorescence (IIF) to detect antinuclear antibodies (ANA) in clinical laboratories. Recently, attention has turned to the identification of the autoantigens that bind to cytoplasmic organelles such as the Golgi complex, endosomes and other "cytoplasmic somes". Three endosome autoantigens include early endosome antigen 1 (EEA1, 160 kDa), cytoplasmic linker protein-170 (CLIP-170, 170 kDa), and lysobisphosphatidic acid (LBPA). Antibodies to EEA1 were seen in a variety of conditions but approximately 40% of the patients had a neurological disease. Despite the prominence of lysosomes in cells and tissues, reports of autoantibodies are limited to the lysosomal antigen h-LAMP-2 and the cytoplasmic antineutrophil antibodies (cANCA). Autoantigens in the Golgi complex include giantin/macrogolgin, golgin-245, golgin 160, golgin-97, golgin 95/gm130, and golgin-67. More recently, there has been an interest in autoantibodies that bind components of the "SMN complex" or the "assemblyosome". Arginine/glycine (RG)-rich domains in components of the SMN complex interact with Sm, like-Sm (LSm), fibrillarin, RNA helicase A (Gu), and coilin proteins, all of which are antigen targets in a variety of diseases. More recently, components of a novel cytoplasmic structure named GW bodies (GWBs) have been identified as targets of human autoantibodies. Components of GWBs include GW182, a unique mRNA-binding protein, like Sm proteins (LSms), and decapping (hDcp1) and exonuclease (Xrn) enzymes. Current evidence suggests that GWBs are involved in the cytoplasmic processing of mRNAs. Autoantibodies to the "cytoplasmic somes" are relatively uncommon and serological tests to detect most of them are not widely available.

Study on the mechanism of epidermal growth factor-induced proliferation of hepatoma cells

AIM: Many growth factors, such as epidermal growth factor (EGF), are associated with the carcinogenesis. EGF plays its role in the proliferation of hepatoma cells through binding with EGF receptor (EGFR) and a series of signal transduction. But the postreceptor pathway is still not clear. In the present experiment, we studied the effect of tyrosine kinase, protein kinase C, Na⁺/H⁺ exchange, calmodulin and voltage-dependent Ca²⁺ channel on EGF-induced hepatoma cell proliferation.

METHODS: Hepatoma cell line SMMC7721 was cultured in RPMI1640 serum-free medium. In order to study the effect of thyrosine kinase, protein kinase C, Na⁺/H⁺ exchange, calmodulin and voltage-dependent Ca²⁺ channel on human heptoma cell proliferation induced by epidermal growth factor (EGF), DNA synthesis rate of hepatoma cells was measured by the method of ³H-TdR incorporation.

RESULTS: EGF (10^-9 M) stimulated the proliferation of heptoma cells significantly (³H-TdR incorporation was 1880 ± 281 cpm/well, P < 0.05), and this effect was significantly inhibited by tyrosine kinase inhibitor genistein (³H-TdR incorporation was 808 ± 209 cpm/well, P < 0.001). Calmodulin inhibitor W-7, protein kinase C inhibitor H-7 and Na⁺/H⁺ exchange inhibitor amiloride individually had significant inhibiting effect on EGF-induced proliferation of hepatoma cells (³H-TdR incorporation was 978 ± 87.3 cpm/well, 1241 ± 147 cpm/well, 1380 ± 189 cpm/well, respectivly, P < 0.001, P < 0.01, P < 0.05), but they all had no effect on the basal level proliferation of cultured hepatoma cells (³H-TdR incorporation was 1284 ± 260 cpm/well, 1179 ± 150 cpm/well, 1392 ± 152 cpm/well, respectivly, ³H-TdR incorporation of the control was 1353 ± 175 cpm/well, P > 0.05). Voltage-dependent Ca²⁺ channel inhibitor verapamil had no inhibition on EGF-induced proliferation of hepatoma cells (³H-TdR incorporation was 1637 ± 133 cpm/well, P > 0.05), it also had no effect on the basal level proliferation of cultured hepatoma cells (³H-TdR incorporation was 1196 ± 12 cpm/well, P > 0.05).

CONCLUSION: Our data suggest that tyrosine kinase, Ca²⁺-calmodulin-dependent pathway, protein kinase C and Na⁺/H⁺ exchange play a critical role in EGF-induced proliferation of hepatoma cells and that the effect of EGF is independent of voltage-dependent Ca²⁺ channel.

p53 autoantibodies in patients with malignant mesothelioma: stability through disease progression

Malignant mesothelioma (MM) generally occurs as a pleural tumour, related to the inhalation of asbestos fibres. It is highly aggressive and largely unresponsive to treatment. The incidence of MM is particularly high in Western Australia because of the extensive blue asbestos mining operations that occurred in the north of the state until 1966. MM is unusual in that mutations in the tumour suppressor gene p53 are rarely observed, whilst over-expression of p53 protein is common. As the level of antibodies directed against p53 is thought to be of prognostic value in some cancers and as MM is known to be immunogenic, we studied a cohort of Western Australian patients to determine the prevalence of anti-p53 antibodies and their value as diagnostic markers or prognostic indicators. 6/88 (7%) of patients had high titres (>2 SD above the mean of controls) of anti-p53 antibodies. There was no correlation between antibody titre and survival. Although 3/38 (8%) of sera obtained from patients exposed to asbestos but prior to a diagnosis of MM contained antibodies, the same proportion of sera obtained from patients exposed to asbestos but who remained disease free also contained antibodies (2/40; 8%). Sera collected sequentially demonstrated a profound temporal stability in the titre of anti-p53 antibodies in patients with MM throughout the course of their illness. These results show that anti-p53 antibodies are observed only at a low frequency in the sera of MM patients and where they do occur, their elicitation is an early event that may be unrelated to antigen load. The occurrence of anti-p53 antibodies does not serve as either a useful prognostic or diagnostic indicator in MM.

Serum ras (p21) as a marker for occupationally derived lung cancer?

Certain subsets of the population are especially sensitive to carcinogens, and this can be determined using molecular biological methods. In the literature there has been evidence presented for the use of p21ras (ras) as a tumor marker for human carcinogenic substances such as asbestos, polycyclic aromatic hydrocarbons, and vinyl chloride in the workplace. In this study we have examined whether serum ras could serve as a biomarker for the early detection of occupationally derived lung cancer, with an emphasis on Schneeberger (radon-induced) lung cancer. Sera were taken from 65 male tumor patients. Fifty-nine patients suffered from primary lung cancer (including 18 patients with Schneeberger lung cancer and 12 patients with asbestos-related lung cancer). Additionally, 29 patients with non-malignant lung disease, and a healthy control group (44) including 32 former uranium miners of SDAG Wismut exposed to ionizing radiation (radon and its decay products) were examined. Ras protein was determined via three different methods: 1) immunoprecipitation followed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting; 2) SDS-PAGE using 5-17% gradient gels followed by Western blotting; 3) pre-incubation with Blue Sepharose, SDS-PAGE on 5-17% gradient gels, and Western blotting. The results show that 1 ng ras protein was measurable in serum standards. This protein could not be detected in patient sera or in sera from any of the study groups. Thus, ras cannot be considered useful as a marker for the early detection of asbestos-induced or Schneeberger lung cancer.