Evaluation of squamous cell carcinoma antigen as a new marker for lung cancer

Clinical utility of pretreatment serum squamous cell carcinoma antigen for prognostication and decision-making in patients with early-stage cervical cancer

Background

To investigate the prognostic role of pretreatment squamous cell carcinoma antigen (SCCA) in early-stage cervical cancer (CC).

Methods

We enrolled 487 cases of pathology-proven early-stage [International Federation of Gynecology and Obstetrics (FIGO) I/II] squamous or adenosquamous CC that were treated from 2012 to 2015. Restricted cubic splines (RCS) with a full Cox regression model were used to evaluate the association between SCCA levels and survival outcomes. Recursive partitioning analysis (RPA) was used to construct a risk stratification model for overall survival (OS). The performance of the RPA-based model was assessed using a receiver operating characteristic (ROC) curve.

Results

RCS analysis revealed an association between SCCA and OS and disease-free survival (DFS); SCCA ⩾2.5 ng/mL was robust for risk discrimination in our cohort. SCCA had an interaction effect with FIGO classification: Patients with FIGO I and SCCA ⩾2.5 ng/mL overlapped with those with FIGO II and SCCA < 2.5 ng/mL for OS [hazard ratio, 1.04 (95% confidence interval (CI): 0.49-2.24), p = 0.903] and DFS [1.05 (0.56-1.98), p = 0.876]. RPA modeling incorporating SCCA (<2.5 ng/mL and ⩾2.5 ng/mL) and FIGO classification divided CC into three prognostic groups: RPA I, FIGO stage I, and SCCA < 2.5 ng/mL; RPA II, FIGO stage I, and SCCA ⩾ 2.5 ng/mL, or FIGO stage II and SCCA < 2.5 ng/mL; and RPA III, FIGO stage II, and SCCA ⩾ 2.5 ng/mL; with 5-year OS of 94.0%, 85.1%, and 73.5%, respectively (p < 0.001). ROC analysis confirmed that the RPA model outperformed the FIGO 2018 stage with significantly improved accuracy for survival prediction [area under the curve: RPA versus FIGO, 0.663 (95% CI: 0.619-0.705] versus 0.621 (0.576-0.664), p = 0.045]. Importantly, the RPA groupings were associated with the efficacy of treatment regimens. Surgery followed by adjuvant treatment had a higher OS (p < 0.01) and DFS (p = 0.024) than other treatments for RPA III, whereas outcomes were comparable among treatment regimens for RPA I-II.

Conclusion

Herein, the role of SCCA for prognostication was confirmed, and a robust clinicomolecular risk stratification system that outperforms conventional FIGO classification in early-stage squamous and adenosquamous CC was presented. The model correlated with the efficacy of different treatment regimes.

Detection and Quantification of Tp53 and p53-Anti-p53 Autoantibody Immune Complex: Promising Biomarkers in Early Stage Lung Cancer Diagnosis

Lung cancer is a leading cause of death worldwide, claiming nearly 1.80 million lives in 2020. Screening with low-dose computed tomography (LDCT) reduces lung cancer mortality by about 20% compared to standard chest X-rays among current or heavy smokers. However, several reports indicate that LDCT has a high false-positive rate. In this regard, methods based on biomarker detection offer excellent potential for developing noninvasive cancer diagnostic tests to complement LDCT for detecting stage 0∼IV lung cancers. Herein, we have developed a method for detecting and quantifying a p53-anti-p53 autoantibody complex and the total p53 antigen (wild and mutant). The LOD for detecting Tp53 and PIC were 7.41 pg/mL and 5.74 pg/mL, respectively. The detection ranges for both biomarkers were 0–7500 pg/mL. The known interfering agents in immunoassays such as biotin, bilirubin, intra-lipid, and hemoglobin did not detect Tp53 and PIC, even at levels that were several folds higher levels than their normal levels. Furthermore, the present study provides a unique report on this preliminary investigation using the PIC/Tp53 ratio to detect stage I–IV lung cancers. The presented method detects lung cancers with 81.6% sensitivity and 93.3% specificity. These results indicate that the presented method has high applicability for the identification of lung cancer patients from the healthy population.

The Non-Cancer Specific Elevation of the Serum Squamous Cell Carcinoma Antigen during the Post-Radiotherapy Follow-Up of Cervical Cancer Patients

The elevation of the serum squamous cell carcinoma (SCC) antigen unrelated to disease progression occurs during the follow-up of patients with cervical cancer treated with radiotherapy. Although known empirically, the incidence and characteristics of this non-cancer specific elevation in SCC remain unclear. Here, we examined the post-treatment kinetics of SCC in 143 consecutive patients with squamous cell carcinoma of the cervix treated with definitive radiotherapy; in all patients, progression-free disease status was confirmed by periodic monitoring for at least 36 months (median, 61 months). We found that the 5-year cumulative incidence of post-treatment SCC elevation was unexpectedly high at 37.3% (59/143 patients), and that 59.3% (35/59) of event-positive patients experienced multiple events. The median peak SCC level for a given event was 2.0 ng/mL (interquartile range, 1.7–2.9 ng/mL). The multivariate analysis showed that renal dysfunction was associated significantly with a greater incidence of SCC elevation (p = 0.046). In addition, the 5-year cumulative incidence of SCC elevation was significantly greater in patients with renal dysfunction than in those without (54.8% vs. 32.9%, respectively; hazard ratio, 2.1 [95% confidence interval, 1.1–4.2]; p = 0.028). These data will be useful for monitoring cervical cancer patients treated with radiotherapy.

CEA Determination in the Follow-Up of Extracolorectal Neoplasms

CEA was initially described as a tumor and organ specific colorectal antigen, but later found by more sensitive methods in other tumors (stomach, pancreas, lung, breast) and in minor amounts in inflammatory, normal adult and fetal organs of the gastrointestinal tract. The main clinical application of CEA concerns its pretherapeutic and serial determination as circulating antigen in serum and other body fluids by means of CEA-specific, commercially available test kits. By clinical studies a significant correlation has been proven between the pretherapeutic serum CEA level and tumor stages and prognosis. Moreover, serial CEA level changes have been shown a valuable monitor following operation or during radio/chemotherapy anticipating and reflecting the clinical course of disease. In combination with newly established tumor markers, the main clinical indication for CEA determination in addition to colorectal cancer concerns monitoring of patients with stomach (+ CA 72-4), lung (+ NSE/SCC) and breast cancer (+ CA 15-3/MCA).

Synergistic increase of oxidative stress and tumor markers in PAH-exposed workers

In this study, we investigated oxidative stress and tumor marker levels of polycyclic aromatic hydrocarbons (PAHs) in 136 coke oven workers and in 60 control subjects, and evaluated the correlation between oxidative stress and tumor marker levels. Questionnaires on basic demographic information were also administered. Significant differences in employment time and percentages of alcohol drinkers were observed between the control and exposed groups. PAH exposure was assessed using urinary 1-hydroxy-pyrene (1-OHP) levels and was found to be significantly higher in workers than in the controls. Significant differences (P<0.001) of MDA, GST, LDH, NSE, Cyfra21-1, and of SCC and TNF-a (P<0.0001 and P<0.05, P<0.001, respectively) levels were observed among controls and coke-oven workers, except for bottom coke oven workers. Associations between age and risk of increased TNF-a, smoking and increased GST activities, and drinking with increased MDA concentrations, were marginal (P=0.055, P=0.048, P=0.057, respectively). The association between smoking with MDA (P=0.004), NSE (P=0.005), SCC (P=0.004) and TNF-a (P<0.001), and drinking with TNF-a levels was significant (P=0.012). In addition, a significant positive correlation between oxidative stress and tumor markers was found in the present study. These results suggest that a synergistic increase of oxidative stress and tumor markers induced by PAHs may play a role in toxic responses for PAHs in coke oven workers.

Serum markers in small cell lung cancer: opportunities for improvement

Lung cancer is one of the leading causes of death from malignancy worldwide. In particular small cell lung cancers, which comprise about 15-20% of all lung cancers, are extremely aggressive and cure rates are extremely low. Therefore, new treatment modalities are needed and detection at an early stage of disease, as well as adequate monitoring of treatment response is essential in order to improve outcome. In this respect, the use of non-invasive tools for screening and monitoring has gained increasing interest and the clinical applicability of reliable, tumor-related substances that can be detected as tumor markers in easily accessible body fluids is subject of intense investigation. Some of these indicators, such as high LDH levels in serum as a reflection of the disease, have been in use for a long time as a general tumor marker. To allow for improved monitoring of the efficacy of new therapeutic modalities and for accurate subtyping, there is a strong need for specific and sensitive markers that are more directly related to the biology and behavior of small cell lung cancer. In this review the current status of these potential markers, like CEA, NSE, ProGRP, CK-BB, SCC, CgA, NCAM and several cytokeratins will be critically analyzed with respect to their performance in blood based assays. Based on known cleavage sites for cytoplasmic and extracellular proteases, a prediction of stable fragments can be obtained and used for optimal test design. Furthermore, insight into the synthesis of specific splice variants and neo-epitopes resulting from protein modification and cleavage, offers further opportunities for improvement of tumor assays. Finally, we discuss the possibility that detection of SCLC related autoantibodies in paraneoplastic disease can be used as a very early indicator of SCLC.

Two novel squamous cell carcinoma antigen-derived HLA-A*0201-binding peptides induce in vitro and in vivo CD8+ cytotoxic T lymphocyte responses

Squamous cell carcinoma antigen (SCCA) is overexpressed in many squamous cell cancers and SCCA‑derived peptide-specific CD8(+) cytotoxic T lymphocytes can display cytotoxicity against tumor cells. In the present study, we screened the SCCA amino acid sequence for potential HLA-A*0201-binding CD8(+) T‑cell epitopes using two predictive computational algorithms. Seven epitope candidates were selected of which SCCA(246-254)(llpneidgl), SCCA(223-231)(sledvqakv), SCCA(328‑336)(vlhkafvev) and SCCA(324‑332)(vlsgvlhka) significantly stabilized HLA-A*0201 molecules on T2 cells. Both SCCA(328‑336) and SCCA(324-332) induced CD8(+) IFN-γ(+) T‑cell responses in HLA-A*0201-positive peripheral blood mononuclear cells as assessed by intracellular cytokine staining. Consistent with this, immunization with either SCCA(328-336) or SCCA(324‑332) effectively elicited CD8(+) IFN-γ(+) T cells in HLA-A*0201 transgenic mice as visualized by IFN-γ ELISPOT assay and intracellular cytokine staining. Furthermore, CD8(+) T cells induced in vitro or in vivo by SCCA(328-336) or SCCA(324-332) demonstrated in vitro cytotoxicity against peptide-pulsed T2 cells and splenocytes, respectively. These novel SCCA‑derived CD8(+) T‑cell epitopes described, herein, may be potentially important components for diagnostic reagents and immunotherapeutic vaccines for the treatment of squamous cell carcinomas.

A clinicopathological study of resected small-sized squamous cell carcinomas of the peripheral lung: prognostic significance of serum carcinoembryonic antigen levels

PURPOSE

The purpose of this retrospective study was to evaluate common clinicopathological factors and clarify the prognostic factors of small-sized peripheral-lung squamous cell carcinomas.

METHODS

We retrospectively reviewed 71 patients with peripheral squamous cell carcinoma ≤3 cm in diameter, who were surgically treated between January 1989 and December 2010. Patients undergoing partial lung resection without lymph node dissection were excluded. The median follow-up for living patients was 63 months.

RESULTS

The overall 3- and 5-year survival rates were 83.9% and 74.7%, respectively.Although the ROC curve of serum carcinoembryonic antigen (CEA) levels showed marginally significance (P = 0.050), multivariate analyses revealed that age (P = 0.043), lymph node metastasis (P = 0.004), and preoperative serum carcinoembryonic antigen (CEA) level (P = 0.037) were independent prognostic factors. For pathologic N0 patients, there was a significant difference for recurrence-free survival based on CEA levels: patients with normal CEA levels (n = 40), 5-year-recurrence-free rate = 93.5%;elevated CEA (n = 14), 5-year-recurrence-free rate = 72.7% (P = 0.0160). The distribution of tumor cells immunoreactive for CEA was significantly associated with serum CEA levels (P = 0.033).

CONCLUSION

Age, lymph node metastasis, and serum CEA level are independent prognostic factors for small-sized peripheral-lung squamous cell carcinoma.

Identification of new genes associated with melanoma

PURPOSE

Repeated failures in melanoma therapy made clear that the molecular mechanisms leading to melanoma are still poorly understood. In this study, we aim to provide a more comprehensive understanding of the transcriptional profiles and signalling pathways associated with melanoma.

METHODS

Gene expression was analysed using the Affymetrix Human Genome U133A 2.0 GeneChip arrays. To avoid culture artifacts, we used microdissected fresh frozen material of 18 melanocytic nevi (MN), 20 primary melanomas (PM) and 20 metastatic melanomas (MM). Statistical analysis was performed with Genomatix Chipinspector, Ingenuity™ Software, SPSS Software and Partek Genomic Suite 6.4. Expression levels of selected transcripts were verified by quantitative real-time RT-PCR and immunostaining of a tissue microarray sampling more than 280 cases of MN, PM and MM with known clinical outcome.

RESULTS

A total of 284 differentially expressed genes was detected in PM compared with MN and 189 genes in MM compared with PM affecting common cancer pathways such as MAPK-, Wnt- and Notch-signalling. Using principal component analysis, the samples could be grouped according to their histological entity. We identified a panel of novel melanoma-associated markers: frizzled-related protein, an antagonist of Wnt; tranducin-like enhancer of split 1, a transcription factor partner of TCF/LEF-1; CNTN1, an activator of Notch signalling; two Serpin peptidase inhibitors, Serpin B3/B4 and the TGF-β family member GDF15, the latter with association to MAPK-signalling.

Heparin enhances serpin inhibition of the cysteine protease cathepsin L

The glycosaminoglycan heparin is known to possess antimetastatic activity in experimental models and preclinical studies, but there is still uncertainty over its mechanism of action in this respect. As an anticoagulant, heparin enhances inhibition of thrombin by the serpin antithrombin III, but a similar cofactor role has not been previously investigated for proteases linked to metastasis. The squamous cell carcinoma antigens (serpins B3 and B4) are tumor-associated proteins that can inhibit papain-like cysteine proteases, including cathepsins L, K, and S. In this study, we show that SCCA-1 (B3) and SCCA-2 (B4) can bind heparin as demonstrated by affinity chromatography, native PAGE gel shifts, and intrinsic fluorescence quenching. Binding was specific for heparin and heparan sulfate but not other glycosaminoglycans. The presence of heparin accelerated inhibition of cathepsin L by both serpins, and in the case of SCCA-1, heparin increased the second order inhibition rate constant from 5.4 x 10(5) to >10(8), indicating a rate enhancement of at least 180-fold. A templating mechanism was shown, consistent with ternary complex formation. Furthermore, SCCA-1 inhibition of cathepsin L-like proteolytic activity secreted from breast and melanoma cancer cell lines was significantly enhanced by heparin. This is the first example of glycosaminoglycan enhancement of B-clade serpin activity and the first report of heparin acting as a cofactor in serpin cross-class inhibition of cysteine proteases. Most importantly, this finding raises the possibility that the anticancer properties of heparin may be due, at least partly, to enhanced inhibition of prometastatic proteases.

WT1 IgG antibody for early detection of nonsmall cell lung cancer and as its prognostic factor

There are urgent needs to develop methods for early detection of nonsmall cell lung cancer (NSCLC) because of its increasing incidence and poor prognosis. Here, we analyzed the production of IgG antibody (WT1 Ab) against WT1 (Wilms' tumor gene) protein that was overexpressed in the majority of NSCLC. Enzyme-linked immuno-sorbent assay showed that WT1 Ab was produced in all of 91 NSCLC patients and 70 healthy individuals and that WT1 Ab titers were significantly higher in NSCLC patients compared with healthy individuals. When the cut-off level of WT1 Ab titers were fixed at mean + 3SD of those in healthy individuals, 26.4% of NSCLC patients had WT1 Ab titers over the cut-off level, and positive rates of WT1 Ab at each clinical stage were 25.0, 30.8 and 38.4% in stage I, II and III NSCLC, respectively. When WT1 Ab was combined with CEA or CYFRA for detection of NSCLC, positive detection rates increased from 25.0 to 34.1 and 31.8%, respectively, in stage I and from 38.4 to 69.2 and 46.1%, respectively, in stage III, but not changed in stage II. Western blot analysis showed that dominant subclass of WT1 Ab was Th1-type IgG2. Interestingly, elevation of WT1 Ab titers was significantly associated with longer disease-free survival in patients with stages I-III NSCLC. These results showed that WT1 Ab could be a useful marker for early detection of NSCLC and its prognostic prediction. These results also suggested that WT1-specific immune responses played an important role in anti-cancer immunity in NSCLC.

Squamous cell carcinoma antigen in lung cancer and nonmalignant respiratory diseases

STUDY OBJECTIVES

Squamous cell carcinoma antigen (SCC) has been found in elevated amounts in patients with squamous cell lung cancer (SQLC). Elevated levels have also been found among patients with nonsquamous cell lung cancer (NSQLC) and in subjects with nonmalignant pulmonary disease (NMPD). The purpose of the current study was to evaluate SCC levels among a large number of patients with SQLC, NSQLC, and NMPD. Six hundred thirty-nine lung cancer patients, including 201 SQLC patients and 299 patients with NMPD, who were diagnosed at our hospital up to 2006 were entered. Serum SCC levels were measured with a commercially available kit.

RESULTS

Elevated levels (>1.5 ng/ml) of SCC were observed in 52.7% of SQLC patients, but in only 14.2% of NSQLC patients. There was a statistically significant difference in positive rate between SQLC and NSQLC patients. None of the NSQLC patients had serum SCC levels greater than 40.0 ng/ml. Among subjects with NMPD, 28.4% had elevated levels of SCC. However, none of the NMPD patients had serum SCC levels greater than 20.0 ng/ml.

CONCLUSIONS

Serum levels of SCC can be elevated (<20.0 ng/ml) in some NMPD patients without coexisting SQLC. Patients with NSQLC and NMPD with elevated SCC levels greater than 40 ng/ml may have coexisting SQLC or squamous cell carcinoma in an extrapulmonary site.

Expression of high-abundance proteins in sera of patients with endometrial and cervical cancers: analysis using 2-DE with silver staining and lectin detection methods

The expression of high-abundance serum proteins in newly diagnosed patients with endometrial adenocarcinoma (EACa), squamous cell cervical carcinoma (SCCa) and cervical adenocarcinoma (ACCa), relative to control female subjects, was analyzed by subjecting serum samples to 2-DE followed by image analysis of the silver-stained protein profiles. The three cohorts of cancer patients demonstrated different altered expression of serum high-abundance proteins compared to negative control women. The expression of alpha1-antitrypsin, alpha1-B glycoprotein, cleaved high-molecular-weight kininogen (light chain) and antithrombin III were consistently altered in all the patients. However, clusterin was upregulated only in the patients with EACa, while those with SCCa and ACCa were typically characterized by the upregulated expression of zinc alpha-2-glycoprotein. The aberrant expression of selective serum proteins in the various cohorts of cancer patients was validated by competitive ELISA as well as by lectin detection. Analysis by using the champedak galactose binding lectin further highlighted an unidentified protein that may be differently glycosylated in the sera of the EACa patients that were studied.

Proteomics-based identification of proteins secreted in apical surface fluid of squamous metaplastic human tracheobronchial epithelial cells cultured by three-dimensional organotypic air-liquid interface method

Squamous cell carcinoma in the lung originates from bronchial epithelial cells that acquire increasingly abnormal phenotypes. Currently, no known biomarkers are clinically efficient for the early detection of premalignant lesions and lung cancer. We sought to identify secreted molecules produced from squamous bronchial epithelial cells cultured with organotypic culture methods. We analyzed protein expression patterns in the apical surface fluid (ASF) from aberrantly differentiated squamous metaplastic normal human tracheobronchial epithelial (NHTBE) and mucous NHTBE cells. Comparative two-dimensional PAGE analysis revealed 174 unique proteins in the ASF of squamous NHTBE cells compared with normal mucociliary differentiated NHTBE cells. Among them, 64 well-separated protein spots were identified by liquid chromatography-tandem mass spectrometry, revealing 22 different proteins in the ASF from squamous NHTBE cells. Expression of six of these proteins [SCC antigen 1 (SCCA1), SCC antigen 2 (SCCA2), S100A8, S100A9, Annexin I, and Annexin II] in the squamous NHTBE cells was further confirmed with immunoblot analysis. Notably, SCCA1 and SCCA2 were verified as being expressed in squamous metaplastic NHTBE cells but not in normal mucous NHTBE or normal bronchial epithelium. Moreover, SCCA1 and SCCA2 expression increased in in vitro lung carcinogenesis model cell lines with increasing malignancy. In summary, we identified proteins that are uniquely secreted from squamous metaplastic primary human bronchial epithelial cells cultured by the organotypic air-liquid interface method. These ASF proteins may be used to detect abnormal lesions in the lung without collecting invasive biopsy specimens.

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.

Enhanced expression of Aggrus (T1alpha/podoplanin), a platelet-aggregation-inducing factor in lung squamous cell carcinoma

Aggrus (T1alpha/podoplanin, known as a specific marker for type I alveolar cells or lymphatic endothelial cells) is a transmembrane sialoglycoprotein that aggregates platelets. Previously, we showed that upregulated expression of Aggrus occurs in colorectal tumors or testicular tumors and could be associated with platelet-aggregating activity and metastatic ability. In testicular tumors, Aggrus is specifically expressed in seminoma. The present study investigates Aggrus expression in human primary lung cancer tissues of different types. Microarray analysis demonstrated that aggrus was significantly expressed in squamous cell carcinoma (10/15; 66.7%). Immunohistochemical analysis also showed that the incidence of positive staining in sections of squamous cell carcinoma (7/8; 87.5%) was higher than that in adenocarcinoma (2/13; 15.4%). Furthermore, Aggrus expression was detected in a squamous cell carcinoma cell line, NCI-H226, by real-time PCR. These findings indicated that overexpression of Aggrus occurred in squamous cell carcinoma of the lung. Therefore, Aggrus could be a useful diagnostic marker for squamous cell carcinoma of the lung.

[CYFRA 21.1 cytosol levels in lung adenocarcinomas. Correlation with other clinico-biological parameters]

INTRODUCTION

Cyfra 21.1 are soluble cytokeratin 19 fragments present in several biological fluids. The aim of this work was to study cyfra 21.1 cytosolic levels in lung adenocarcinomas and their possible correlation with other clinical-biological parameters.

PATIENTS AND METHODS

Cyfra 21.1 was determined, using an immunoradiometric assay (CIS BioInternational. France), in 58 tissue samples of lung adenocarcinomas patients. Other parameters included in the study were the following: clinical stage, histological grade, ploidy, S-phase cellular fraction, as well as cathepsin D, CA 125 and hyaluronic acid levels in cytosols. Likewise, AH, erbB2 oncoprotein, CD44s, CD44v5 and CD44v6 levels in cell surfaces were assayed.

RESULTS

Cyfra 21.1 cytosolic levels oscillated between 24.8 and 6,774 ng/mg prot. (median 1,147.5) and were higher (p:0.00074) than those observed in 16 normal lung samples of the same patients. We did not observe any statistically significant differences in cyfra 21.1 values when clinical stage, ploidy, S-phase and histological grade were considered. When lung adenocarcinomas were classified according to cyfra 21.1 positivity, using 1,499 ng/mg prot. as cut-off, which represents the 75th percentile of the whole group, we noted that positive cases had higher levels of cathepsin D (p:0.00218), cytosolic hyaluronic acid (p:0.02947), erbB2 protein (p:0.06272) and CA 125 (p:0.07243) than negative carcinomas.

CONCLUSIONS

These results suggest the possibility that high cytosolic cyfra 21.1 levels could be associated with a poor outcome in lung adenocarcinomas.

Immunoreactivity of recombinant squamous cell carcinoma antigen and leupin/SCCA-2: implications for tumor marker detection

OBJECTIVES

Squamous cell carcinoma antigen (SCCA) is a member of the serpin superfamily, and has been used as a serological tumor marker for cervical squamous cell carcinomas. We have identified a closely related serpin gene, leupin (SCCA-2), which may be the fraction previously thought to be the acidic isoform of SCCA. The purpose of this study is to isolate the individual recombinant proteins, to examine their reactivity with current immunological detection methods, and to use a gene-specific method to examine their expression in the uterine cervix.

METHODS

We have expressed and purified recombinant forms of SCCA and leupin individually. The proteins were characterized with respect to their isoelecric points and their reactivity with the monoclonal antibody from the current tumor marker diagnostic immunoassay (IMx SCC). Reverse transcription polymerase chain reaction (RT-PCR) with gene-specific primers was used to examine expression of both genes.

RESULTS

Isoelectric focusing shows that leupin is the more acidic antigen with a determined pI for recombinant leupin (rLeupin) of 6.01, with rSCCA having a pI of 6.17. The IMx SCC monoclonal antibody recognized both rSCCA and rLeupin in immunoassays and immunoblots and both genes are expressed in normal cervix and in cervical carcinoma tissue.

CONCLUSIONS

The findings from this study suggest that all previous clinical studies examining SCCA expression have used methodology that detects two gene products. The confirmation that leupin or SCCA-2 is the more acidic protein and that its expression is significantly elevated in cervical cancer suggests that this gene product may be the more important tumor marker.

Prognosis in bronchogenic squamous cell carcinoma groups divided according to serum squamous cell carcinoma-related antigen and cytokeratin 19 fragment levels

We examined differences in the 2-year survival rate in bronchogenic squamous cell carcinoma patients with normal serum levels of both cytokeratin 19 fragment (CYFRA 21-1) and squamous cell carcinoma-related antigen (SCC) (NL group, n=15), patients with only increased SCC levels (SCC+ group, n=14), patients with only increased CYFRA 21-1 levels (CYFRA+ group, n=14), and patients with elevated levels of both CYFRA 21-1 and SCC (EL group, n=65). The 2-year survival rates for the CYFRA+ and the EL group were lower than those for the SCC+ group and the NL group (0 and 12.9% vs. 66.7 and 85.6%, log rank: p<0.0001, Wilcoxon: p<0.0001). However, there were no differences between the rate for the SCC+ and the NL group and between that for the CYFRA+ and the EL group. Serum carcinoembryonic antigen (CEA) levels increased in the patients with the elevated CYFRA 21-1 levels. This results suggest that there may be some differences between squamous cell carcinoma patients with increased CYFRA 21-1 levels and those with normal levels and that it is CYFRA 21-1 levels, not SCC levels, that relate to the prognosis.

Tumor markers in lung cancer: does the method of obtaining the cut-off point and reference population influence diagnostic yield?

OBJECTIVES

The aim of this study was to evaluate the clinical usefulness of the tumor markers CA125, CEA, NSE, SCC, and TPS in a group of patients with lung cancer. We estimated the influence of the method for choosing the cut-off point and of considering as a reference population either healthy controls or patients with some form of non-neoplastic pulmonary disease (NNPD).

DESIGN AND METHODS

The tumor markers were determined using enzyme immunoassay techniques, and their diagnostic yield was evaluated using ROC curves and their correlation with the percentages between false and true positives. The diagnostic parameters of the tumor markers are presented in 116 patients with lung cancer and compared with a group of 25 healthy controls and another group of 80 patients with some form of NNPD. We determined on the one hand the cut-off points resulting from the best sensitivity-specificity balance in the ROC curves and on the other those resulting from considering a specificity of 95%. With the two cut-offs we studied the different diagnostic parameters: sensitivity, specificity and accuracy or area below the ROC curve.

RESULTS

Optimum diagnostic yield is obtained when we choose the cut-off point determined by the best balance of sensitivity and specificity in the ROC curves and take a healthy population as a reference group. The cut-off values for CA125, CEA, NSE, SCC, and TPS were 24 U/mL, 2.8 ng/mL, 9.8 ng/mL, 1.6 ng/mL, and 67.8 U/L, respectively.

CONCLUSIONS

Our results suggest that in future studies on tumor markers, a group of healthy subjects should be used as a reference population and ROC curves should be used to obtain the optimum cut-offs.

Squamous cell carcinoma antigen in patients with cancer of the larynx

The purpose of this study was to evaluate the clinical usefulness of squamous cell carcinoma antigen (SCC Ag) in patients with squamous cell carcinoma of the larynx. Plasma specimens were obtained from 70 patients with cancer of the larynx before and after treatment and during follow-up. Disease status and the marker levels were determined blind to each other. Microparticle enzyme immunoassay (IMx SCC) was used to measure the SCC Ag level. Applying standard normal limits the sensitivity of the marker at diagnosis was 25.7%. SCC Ag levels were generally lower after therapy than before. Relapse occurred more often in patients with an abnormal pretreatment SCC Ag level, which was more frequent in those with nodal invasion. The marker level increased in 70% of the patients with relapse before the clinical detection of recurrence. SCC Ag is of limited usefulness in the primary diagnosis of cancer of the larynx, but is useful in detecting recurrence of cancer.

Identification of human skin from a tissue fragment by detection of squamous cell carcinoma-related antigen using an enzyme immunoassay

A new method of identifying human skin from a tissue fragment by detection of squamous cell carcinoma-related (SCC) antigen, using an enzyme immunoassay, was developed. When an extract was prepared from 0.1 g human skin homogenized with 1 ml of phosphate buffered saline, this method was able to detect SCC antigen in extracts diluted 10(2)-fold. There was no difference in the detection limit between individuals. Species specificity was good, and there was no cross reaction observed with skins from animals. Our method could also discriminate between skin and other organs or tissues, except for esophagus and lung. A practical case to which this method was applied is presented.

CYFRA 21-1 enzyme-linked immunosorbent assay. Evaluation as a tumor marker in non-small cell lung cancer

BACKGROUND

The CYFRA 21-1, a newly developed sandwich enzyme-linked immunosorbent assay (ELISA), was used to measure soluble cytokeratin 19 fragment in serum that is expressed in simple epithelium and its malignant counterpart. The present study was designed to investigate whether CYFRA 21-1 is a sensitive and specific tumor marker for non-small cell lung cancer.

METHODS

CYFRA 21-1 assay, using two specific monoclonal antibodies (KS 19.1 and BM 19.21) for cytokeratin 19, was measured in 312 serum samples, including 164 lung cancer, 118 benign pulmonary disease, and 30 healthy individuals. The sensitivity of CYFRA 21-1 was also compared with two other markers, carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC), in 164 patients with lung cancer.

RESULTS

The median value of healthy individuals was 1.3 ng/mL (95th percentile 1.8). In patients with benign pulmonary diseases, the median was 1.5 ng/mL (95th percentile 2.9). There is no significant difference between sexes, smoking habit, and the subgroups of benign pulmonary disease, such as tuberculosis, pneumonia, or COPD. Using the cutoff value of 3.3 ng/mL, defined at 95% specificity for benign lung disease, the sensitivities of CYFRA 21-1 for squamous cell carcinoma (n=74), adenocarcinoma (n=54), undifferentiated large cell carcinoma (n=11), and small cell lung cancer (n=25) were 62%, 39%, 36%, and 20%, respectively. Despite the cell types, the sensitivities of CYFRA 21-1 in non-small cell lung cancer (NSCLC, n=169) were 51% (CEA 42%, SCC 20%). The sensitivity of CEA was significantly higher in patients with adenocarcinoma (58%) than other markers; while in patients with squamous cell carcinoma, CYFRA 21-1 assay has the highest sensitivity. The median level of CYFRA 21-1 in squamous cell carcinoma is significantly higher than that of other cell types (Mann-Whitney test, p<0.001). The serum level and sensitivity of CYFRA 21-1 were well correlated with staging and tumor size in squamous cell carcinoma. The CYFRA 21-1 values were measured for monitoring progression of disease in 20 patients with squamous cell carcinoma. There is significant difference in paired observation of CYFRA 21-1 level in patients with progressive disease (Wilcoxon signed-rank test, p<0.05), but no difference was observed in patients with stabilized disease (p>0.1).

CONCLUSION

For patients with NSCLC, especially in squamous cell carcinoma, CYFRA 21-1 is not only a sensitive and specific tumor marker, but also may be a useful adjunctive marker for disease monitoring.

CEA, CYFRA21-1 and SCC in non-small cell lung cancer

CEA, SCC and CYFRA 21-1 were measured in samples of serum coming from 105 'Non small cell lung cancer' (NSCLC) patients. The present study has been carried out to compare these markers, to analyse their prognostic significance and to determine the best combination of tumor markers. The median value and interquartile range were: CYFRA 21-1: 2,3 ng/ml, CEA: 3,7 ng/ml, SCC: 1,2 ng/ml. CEA demonstrated higher values in adenocarcinomas (P = 0.04). SCC and CYFRA 21-1 were comparable in the different histologic groups. CYFRA 21-1 and CEA values were dependant on tumor stage. Advanced tumors (T3 and T4) demonstrated higher serum CYFRA 21-1 level (P = 0.0006). CYFRA 21-1 was higher than 3,3 ng/ml in 36% of patients. CEA was higher than 5 ng/ml in 38% of patients and SCC was higher than 2 ng/ml in 27% of patients. Patients with a high CEA and CYFRA21-1 serum level had a shorter survival than those with a normal serum level. In a Cox regression analysis four variables (TNM stage, age, CYFRA 21-1 and CEA level) were found to be significant in the prediction of survival; CYFRA 21-1 level had the lowest P value (P = 0.0002). The current study suggests the use of a combination of CEA and CYFRA 21-1 in the clinical care of NSCLC.

Clinical usefulness of CYFRA assay in diagnosing lung cancer: measurement of serum cytokeratin fragment

We evaluated the diagnostic usefulness of measurement of the soluble cytokeratin 19 fragment, a new tumor marker, in 391 patients with lung cancer and in 424 patients with benign lung diseases. Serum concentrations of cytokeratin 19 fragment were measured by a sandwich ELISA (CYFRA). The cut-off value was defined as 3.5 ng/ml, which is associated with a specificity of 85% for benign lung diseases. CYFRA had a high sensitivity (57.5%) in all subjects with lung carcinoma, and had a higher sensitivity for squamous cell carcinoma (73.1%, n = 141) than squamous cell carcinoma-related antigen (61.0%). CYFRA was associated with a relatively high sensitivity (42.1%) in early-stage squamous cell carcinoma (stage I, based on the classification of the Japan Lung Cancer Society), but the CYFRA titer was higher in advanced squamous cell carcinoma than in early-stage squamous cell carcinoma. Our findings suggest that CYFRA is potentially useful for diagnosis and monitoring of lung carcinoma, especially for squamous cell carcinoma.

Assessment of urinary beta-core fragment of human chorionic gonadotropin as a new tumor marker of lung cancer

BACKGROUND

Some patients with lung cancer have been found to have elevated levels of serum immunoreactive human chorionic gonadotropin (hCG)/hCG beta (IR-beta), but it is uncertain whether it would be valuable as a tumor marker. Recently, IR-beta has been demonstrated to consist of at least three different molecules, intact hCG, free hCG beta, and hCG beta-core fragment (beta-CF), in body fluids. In this study, the authors qualitatively analyzed IR-beta in the serum and urine of patients with lung cancer and assessed its clinical usefulness as a tumor marker.

METHODS

Highly sensitive and specific enzyme immunoassays were established to measure intact hCG, free hCG beta, and beta-CF in the serum and urine of patients with lung cancer.

RESULTS

Of 99 patients with lung cancer, almost half of the patients achieved positive values of IR-beta in the urine, although only 12 had elevated values of IR-beta in the serum. The greater part of the elevated urinary IR-beta was identified to be beta-CF by gel chromatography on Sephadex G-100 (Pharmacia LKB Biotechnology, Tokyo, Japan), leading the authors to assess its usefulness as a tumor marker for lung cancer. Based on the cutoff value (0.2 ng/mg of creatinine) from healthy subjects, the overall positive rate of urinary beta-CF for lung cancer was 48.5% (48 of 99 patients). The incidence of the marker increased with stage of disease, from 35.7% (15 of 42) in Stage I and 35.7% (5 of 14) in Stage II to 62.5% (20 of 32) in Stage III and 72.7% (8 of 11) in Stage IV. These positive rates exceeded or equaled those of the serum tumor markers, carcinoembryonic antigen, and squamous cell carcinoma (SCC)-related antigen, measured simultaneously in the same patients. The author were encouraged that there was no significant difference in the positive rates of urinary beta-CF between two major types of lung cancer: adenocarcinoma (49.2%) and SCC (45.2%). Immunohistochemical study revealed positive staining of IR-beta in the cancer tissues from 5 of 12 patients with elevated levels of IR-beta, in which most of the positive cases had the elevated levels of serum free hCG beta (> 0.5 ng/ml) and/or urinary beta-CF (> 1.0 ng/mg of creatinine).

CONCLUSIONS

Ectopic production of IR-beta by lung cancer is not rare, and urinary beta-CF might be a potential tumor marker of lung cancer.

Quantitative analysis of carcinoembryonic antigen, squamous cell carcinoma antigen, CA 125, and CA 50 cytosolic content in non-small cell lung cancer

BACKGROUND

The cytosolic content of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC), CA 125, and CA 50 antigens in non-small cell lung cancer (NSCLC) is analyzed in this study. The aim was to ascertain the relationship between tumor marker content and the clinicopathologic aspects of this neoplasm.

METHODS

Lung tissue samples were obtained at the time of surgery from 75 patients with NSCLC patients (samples of tumor and unaffected tissue) and 29 subjects with idiopathic pneumothorax. All determinations were performed on cytosols obtained from lung specimens. CEA and CA 125 were determined by enzyme immunoassay, SCC antigen by radioimmunoassay, and CA 50 by fluoroimmunoassay. Tumor marker content was analyzed by TNM stage, histologic type, tumor grade, and number of atypias.

RESULTS

The concentration of the four markers was significantly higher in cytosol obtained from neoplastic tissue. Frequency of elevated levels of CEA was higher in adenocarcinoma (87% cases expressing high levels of the marker), SCC antigen in epidermoid carcinoma (65% expressing high levels), and CA 125 in large cell carcinomas (100% expressing high levels). No association was found between TNM stage and cytosol concentration for any of the four markers. CEA exhibited significantly greater concentration in well differentiated tumors, whereas this was true of CA 125 in poorly differentiated tumors. CA 125 content was higher in tumors with more atypia.

CONCLUSIONS

Cytosolic quantification of tumor markers may be an adjuvant mechanism to evaluate histologic subtypes of non-small cell lung cancer and identification of tumors with poorly differentiated features.

Serum glutathione S-transferase-pi level as a tumor marker for non-small cell lung cancer. Potential predictive value in chemotherapeutic response

BACKGROUND

Resistance to chemotherapeutic agents is a major problem in non-small cell lung cancer (NSCLC) chemotherapy, and recent studies have indicated that glutathione S-transferase-pi (GST-pi) may play an important role in the resistance of cancer cells to alkylating agents that include platinum compound.

METHODS

GST-pi in serum of 121 patients with NSCLC was measured by a sandwich enzyme-linked immunosorbent assay, and the serum concentrations of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen, and neuron-specific enolase (NSE) were also examined. Serum levels of these tumor markers were also evaluated in relation to therapeutic response in 69 patients who received combination chemotherapy with platinum compound.

RESULTS

Fifty of 121 patients with NSCLC (41.3%) showed elevated serum GST-pi levels above a cutoff value of 34.8 ng/ml (mean + two standard deviations in 30 healthy control subjects). The positive rate of GST-pi in patients with NSCLC was higher than those of CEA (37.2%), SCC (15.7%), and NSE (14.9%). The mean pretreatment GST-pi level was significantly lower in patients with a partial response to chemotherapy than in those with no response (26.9 +/- 11.3 ng/ml versus 38.8 +/- 16.7 ng/ml; P < 0.003). Among patients with elevated levels of pretreatment serum GST-pi, only 13.8% (four of 29) responded to the combination chemotherapy, whereas partial response was observed in 40.0% of patients (16 of 40) with serum GST-pi concentration below the cutoff level (P < 0.02). Neither CEA, SCC, nor NSE showed such a relationship.

CONCLUSIONS

The serum GST-pi level may have limited value as a tumor marker for NSCLC: Interestingly, pretreatment serum GST-pi levels may be a useful parameter for predicting therapeutic response to combination chemotherapy regimens that include platinum compound.

Squamous cell carcinoma antigen (SCC Ag) in the diagnosis and prognosis of lung cancer

OBJECTIVE

We have studied the usefulness of squamous cell carcinoma antigen (SCC Ag) in diagnosis and prognosis of lung cancer (LC).

MATERIAL AND METHODS

We have measured the serum SCC Ag levels in 388 subjects: 69 healthy persons; 103 with nonmalignant lung diseases (NMLD); 24 with lung metastasis of extrapulmonary origin (LMEO); and 192 with LC (88, with squamous cell carcinoma [SCC] type). In 55 with SCC, we analyzed the survival time.

RESULTS

Serum SCC Ag was above 2.5 ng/ml in 1.4 percent of healthy persons; 2.9 percent of those with NMLD; 8.3 percent of those with LMEO; and 27.6 percent of those with LC. Such percentage was 47.7 percent in SCC. In this type, there were significant differences according to the extent of disease (61.6 percent in advanced stages, and 26.5 percent in localized stages, p = 0.002). In the other types, the sensitivity was substantially lower. The initial SCC Ag has prognostic significance (p = 0.02) in the univariate analysis, but it loses such significance in a multivariate model, including the stage.

CONCLUSIONS

Therefore, we do not recommend this marker in the clinical management of patients with LC, even it can be useful in the differential diagnosis if used in combination with other markers.

Expression of squamous cell carcinoma-associated antigen in grade 3 pT1 transitional cell carcinoma of the bladder and prediction of its progression and intravesical recurrence

BACKGROUND

Among superficial transitional cell carcinomas (TCC) of the bladder, Grade 3 pT1 disease is associated with a higher risk of progression and intravesical recurrence. The authors determined whether or not squamous cell carcinoma-associated antigen (SCC antigen) could predict clinical behavior of Grade 3 pT1 disease.

METHODS

SCC antigen was immunohistochemically stained in Grade 3 pT1 TCC of the bladder that had been fixed in formaldehyde solution and embedded in paraffin. Patients were followed up, and disease progression and recurrence were identified. Disease progression was defined as histologically verified muscle invasion or clinically detectable distant metastasis, including pelvic lymph node metastasis.

RESULTS

SCC antigen in the cytoplasm was positively identified with immunohistochemical staining in 21 of 55 patients with the disease. Of 21 patients with positive SCC antigen in the cytoplasm, 8 experienced disease progression, whereas there was progression in 5 of 34 patients with negative antigen. The nonprogression rate of Grade 3 pT1 carcinomas with positive antigen in the cytoplasm was significantly lower than that for those with negative antigen. The disease-free rate also was clearly lower in the positive carcinoma than in the negative. Multivariate analysis confirmed that SCC antigen in the cytoplasm was the only significant variable independently affecting progression and intravesical recurrence of the disease.

CONCLUSIONS

The results suggested that immunohistochemical expression of SCC antigen in the cytoplasm is closely linked with a higher risk for progression and intravesical recurrence of Grade 3 pT1 disease. Detection of the antigen can help to more accurately predict the clinical course of the disease.

Diagnostic value of sialic acid in malignant pleural effusions

In this study, we measured pleural fluid and serum sialic acid levels in 70 consecutive patients hospitalized with pleural effusions and serum sialic acid concentrations in 20 healthy individuals chosen as control group. The cause of 26 pleural effusions was malignancy, and diseases other than malignant neoplasms were determined as the cause of 44 cases. Mean serum sialic acid levels in the patients with malignancies were higher than the levels in patients with nonmalignant diseases and the control group. Mean sialic acid level in the patients with nonmalignant diseases was increased compared with control group, but this increase was not as high as that in the patients with malignancies. In the patients with malignant neoplasms, mean pleural fluid sialic acid content was also higher than that found in other diseases. Sialic acid concentration of pleural fluid was correlated with serum concentration. However, pleural fluid to serum sialic acid ratio in malignant diseases was greater than that in the others. The specificity and sensitivity of pleural fluid sialic acid level in excess of 0.075 mg/ml in distinguishing malignant effusions were 68 percent and 77 percent, respectively. These values for pleural fluid/serum sialic acid ratio with the cut-off level of 0.7 were 55 percent and 65 percent. Our findings indicate that determination of sialic acid level in malignant pleural effusions has a diagnostic value.

Tumor-associated antigen 43-9F is of prognostic value in squamous cell carcinoma of the lung. A retrospective immunohistochemical study

BACKGROUND

Squamous cell lung carcinoma (SLC), the most frequent type of lung cancer, generally is treated surgically and its prognosis is poor. The only current clinically useful prognostic criterion is lymph node staging (TNM classification). Expression of a novel tumor-associated carbohydrate epitope Gal beta 1-3[Fuc alpha 1-4]GlcNAc beta 1-4[Fuc alpha 1-3]GlcNAc beta 1-3 Gal beta 1-4Glc identified by the 43-9F monoclonal antibody (MoAb) is associated with the growth pattern of SLC cell lines in athymic mice and in vitro. This implies that the 43-9F epitope may be related to tumor progression in patients with SLC and that, as such, it could be of prognostic value.

METHODS

Primary tumor specimens from 231 patients with lung carcinoma (130 with SLC, 64 with adenocarcinoma, 10 with small cell carcinoma, 16 with large cell carcinoma, and 11 with adenosquamous carcinoma) were examined by immunohistochemical studies on formalin-fixed, paraffin-embedded tissue samples for immunoreactivity with an MoAb to the 43-9F antigen. Univariate and step-wise Cox regression analyses were used to compare survival time by histopathologic diagnosis, smoker status, TNM classification, and type of surgical treatment.

RESULTS AND CONCLUSIONS

Patients with 43-9F epitope-positive SLC tumors had a significantly (P less than 0.01) better prognosis than patients with epitope-negative tumors. In contrast, no association was seen between 43-9F epitope expression and survival time for patients with lung adenocarcinomas. Further, the prognostic value of 43-9F expression in SLC was found to be superior to the N-classification with the added advantage that it requires access only to primary tumor tissue and thus is available before therapy.