Serum autoantibody measurement for the detection of hepatocellular carcinoma

Cancer-Testis Gene Biomarkers Discovered in Colon Cancer Patients

In Saudi Arabia, colon cancer (CC) is the most prevalent cancer in men and the third most common cancer in women. Rather than being detected through screening programs, most CC cases are diagnosed mainly during clinical exams. Because of the slow growth of CC and its ability to be treated at an early stage, screening for CC can reduce the incidence of death and mortality. Consequently, there is an urgent need to identify a potential new cancer-specific biomarker for detecting early illness. Much research has been conducted on distinct antigen classes as potential new cancer-specific biomarkers for the early identification of malignancy. The cancer-testis antigens (CTAs) are one such category of antigens, with protein presence largely normally confined to human germ line cells in the testis and aberrantly produced in some cancer cells. CTAs are potentially valuable for use as cancer biomarkers and in cancer therapeutics due to their distinctive expression pattern. The aim of this current study was to identify potential cancer-testis (CT) gene biomarkers in Saudi Arabian CC patients. In this study, a total of 20 matching CC and normal colon (NC) tissues were obtained from the Saudi population. Any genes that showed expression in CC tissues but not in matching NC tissues were subsequently verified for mRNA expression in eight breast and eight leukemia malignancies using RT-PCR to determine the specificity of any CC biomarkers. CTAG1A, SPZ1, LYZL6, SCP2D1, TEX33, and TKTL2 genes were expressed in varying numbers of CC tissues compared to no measurable expressions in all NC tissue specimens, making these genes suitable potential candidates for CC markers. The most frequently expressed CT genes in CC patients were CTAG1A (35%) and SCP2D1 (35%), followed by TKTL2 (25%), SPZ1 (20%), LYZL6 (15%), and TEX33 (5%). The LYZL6 gene shows a weak RT-PCR product in 25% of breast cancer (BC) patients but not in leukemia patients. The SCP2D1 gene appears to display expression in all leukemia patients but not in the BC patients. TKTL2 expression was also observed in 50% of leukemia samples but not in the BC samples. More experiments at the protein level and with a larger cohort of patients are required to evaluate this finding.

Immunodiagnostic Biomarkers for Hepatocellular Carcinoma (HCC): The First Step in Detection and Treatment

Hepatocellular carcinoma (HCC) exerts huge effects on the health burden of the world because of its high mortality and poor prognosis. HCC is often clinically detected late in patients. If HCC could be detected and treated earlier, the survival rate of patients will be greatly improved. Therefore, identifying specific biomarkers is urgent and important for HCC. The liver is also recognized as an immune organ. The occurrence of HCC is related to exacerbation of immune tolerance and/or immunosurveillance escape. The host immune system plays an important role in the recognition and targeting of tumor cells in cancer immunotherapy, as can be seen from the clinical success of immune checkpoint inhibitors and chimeric antigen receptor (CAR) T cells. Thus, there is a pressing medical need to discover immunodiagnostic biomarkers specific to HCC for understanding the pathological mechanisms of HCC, especially for immunotherapy targets. We have reviewed the existing literature to summarize the immunodiagnostic markers of HCC, including autoantibodies against tumor-associated antigens (TAAs) and exosomes, to provide new insights into HCC and early detection of this deadly cancer.

Value of anti-p53 antibody as a biomarker for hepatocellular carcinoma: Evidence from a meta-analysis

INTRODUCTION

The incidence of hepatocellular carcinoma (HCC) ranks sixth in the world, but its mortality is the third highest due to the lack of early diagnostic markers. Nowadays, the increase of autoantibody levels has been found in many cancers, and many studies have begun to pay attention to the detection of anti-p53 antibodies in HCC. The purpose of this study is to quantitatively and comprehensively analyze the potential diagnostic value of anti-p53 autoantibodies in HCC METHODS:: English articles up to November 2019 were collected. The overall sensitivity and specificity were calculated. Besides, the positive likelihood ratio, negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic curves of the overall diagnostic accuracy of anti-p53 antibody were calculated by STATA software. Finally, according to the heterogeneity of the results, the subgroup analysis, and the publication bias were performed.

RESULTS

A total of 16 eligible studies were incorporated into this meta-analysis, including 1323 patients with HCC and 1896 control. The pooled sensitivity was 0.28(0.17-0.41) and specificity was 0.98 (0.95-0.99). The pooled DOR was 10.44 (6.31-17.29) and the pooled NLR was 0.74 (0.63-0.86). The area under ROC curve of symmetrical ROC was 0.840.

CONCLUSIONS

The anti-p53 antibody has a high specificity for HCC, but the low sensitivity is not perfect and would limit the clinical application. The anti-p53 antibody would help rule out HCC but not help rule in HCC for early diagnosis. Whether combined as a diagnostic panel with other biomarkers or laboratory tests may prove useful requires further study.

Six autoantibodies as potential serum biomarkers of hepatocellular carcinoma: A prospective multicenter study

Serum autoantibodies have been reported to react with tumor-associated antigen (TAA) in various cancers. This multicenter study evaluated the diagnostic and prognostic value of six autoantibodies against a panel of six hepatocellular carcinoma (HCC)-associated antigens, including Sui1, p62, RalA, p53, NY-ESO-1 and c-myc. A total of 160 patients with HCC and 74 healthy controls were prospectively enrolled from six institutions. Serum antibody titers were determined by enzyme-linked immunosorbent assays. The sensitivities were 19% for Sui1, 18% for p62, 17% for RalA, 11% for p53, 10% for NY-ESO-1 and 9% for c-myc. Overall sensitivity of the TAA panel (56%) was higher than that of α-fetoprotein (41%, P < .05). The combined sensitivity of the TAA panel and α-fetoprotein was significantly higher than that of α-fetoprotein alone (P < .001). The difference in overall survival of TAA panel-positive and panel-negative patients was significant when the Stage I/II patients were combined (P = .023). Overall survival was worse in NY-ESO-1 antibody-positive than in NY-ESO-1 antibody-negative patients (P = .002). Multivariate analysis found that positivity for the TAA panel was independently associated with poor prognosis (P = .030). This TAA panel may have diagnostic and prognostic value in the patients with HCC.

Serological Biomarkers for Early Detection of Hepatocellular Carcinoma: A Focus on Autoantibodies against Tumor-Associated Antigens Encoded by Cancer Driver Genes

Substantial evidence manifests the occurrence of autoantibodies to tumor-associated antigens (TAAs) in the early stage of hepatocellular carcinoma (HCC), and previous studies have mainly focused on known TAAs. In the present study, protein microarrays based on cancer driver genes were customized to screen TAAs. Subsequently, autoantibodies against selected TAAs in sera were tested by enzyme-linked immunosorbent assays (ELISA) in 1175 subjects of three independent datasets (verification dataset, training dataset, and validation dataset). The verification dataset was used to verify the results from the microarrays. A logistic regression model was constructed within the training dataset; seven TAAs were included in the model and yielded an area under the receiver operating characteristic curve (AUC) of 0.831. The validation dataset further evaluated the model, exhibiting an AUC of 0.789. Remarkably, as the aggravation of HCC increased, the prediction probability (PP) of the model tended to decrease, the trend of which was contrary to alpha-fetoprotein (AFP). For AFP-negative HCC patients, the positive rate of this model reached 67.3% in the training dataset and 50.9% in the validation dataset. Screening TAAs with protein microarrays based on cancer driver genes is the latest, fast, and effective method for finding indicators of HCC. The identified anti-TAA autoantibodies can be potential biomarkers in the early detection of HCC.

Tumor-associated autoantibodies in combination with alpha-fetoprotein for detection of early stage hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) continues to be a leading challenge in modern oncology. Early detection via blood-based screening tests has the potential to cause a stage-shift at diagnosis and improve clinical outcomes. Tumor associated autoantibodies (TA-AAbs) have previously shown the ability to distinguish HCC from patients with high-risk liver disease. This research aimed to further show the utility of TA-AAbs as biomarkers of HCC and assess their use in combination with Alpha-fetoprotein (AFP) for detection of HCC across multiple tumor stages.

METHODS

Levels of circulating G class antibodies to 44 recombinant tumor associated antigens and circulating AFP were measured in the serum of patients with HCC, non-cancerous chronic liver disease (NCCLD) and healthy controls via enzyme-linked immunosorbent assay (ELISA). TA-AAb cut-offs were set at the highest Youden's J statistic at a specificity ≥95.00%. Panels of TA-AAbs were formed using net reclassification improvement. AFP was assessed at a cut-off of 200 ng/ml.

RESULTS

Sensitivities ranged from 1.01% to 12.24% at specificities of 95.96% to 100.00% for single TA-AAbs. An ELISA test measuring a panel of 10 of these TA-AAbs achieved a combined sensitivity of 36.73% at a specificity of 89.89% when distinguishing HCC from NCCLD controls. At a cut-off of 200 ng/ml, AFP achieved a sensitivity of 31.63% at a specificity of 100.00% in the same cohort. Combination of the TA-AAb panel with AFP significantly increased the sensitivity for stage one (40.00%) and two (55.00%) HCC over the TA-AAb panel or AFP alone.

CONCLUSIONS

A panel of TA-AAbs in combination with AFP could be clinically relevant as a replacement for measuring levels of AFP alone in surveillance and diagnosis strategies. The increased early stage sensitivity could lead to a stage shift with positive prognostic outcomes.

NY-ESO-1 Based Immunotherapy of Cancer: Current Perspectives

NY-ESO-1 or New York esophageal squamous cell carcinoma 1 is a well-known cancer-testis antigen (CTAs) with re-expression in numerous cancer types. Its ability to elicit spontaneous humoral and cellular immune responses, together with its restricted expression pattern, have rendered it a good candidate target for cancer immunotherapy. In this review, we provide background information on NY-ESO-1 expression and function in normal and cancerous tissues. Furthermore, NY-ESO-1-specific immune responses have been observed in various cancer types; however, their utility as biomarkers are not well determined. Finally, we describe the immune-based therapeutic options targeting NY-ESO-1 that are currently in clinical trial. We will highlight the recent advancements made in NY-ESO-1 cancer vaccines, adoptive T cell therapy, and combinatorial treatment with checkpoint inhibitors and will discuss the current trends for future NY-ESO-1 based immunotherapy. Cancer treatment has been revolutionized over the last few decades with immunotherapy emerging at the forefront. Immune-based interventions have shown promising results, providing a new treatment avenue for durable clinical responses in various cancer types. The majority of successful immunotherapy studies have been reported in liquid cancers, whereas these approaches have met many challenges in solid cancers. Effective immunotherapy in solid cancers is hampered by the complex, dynamic tumor microenvironment that modulates the extent and phenotype of the antitumor immune response. Furthermore, many solid tumor-associated antigens are not private but can be found in normal somatic tissues, resulting in minor to detrimental off-target toxicities. Therefore, there is an ongoing effort to identify tumor-specific antigens to target using various immune-based modalities. CTAs are considered good candidate targets for immunotherapy as they are characterized by a restricted expression in normal somatic tissues concomitant with a re-expression in solid epithelial cancers. Moreover, several CTAs have been found to induce a spontaneous immune response, NY-ESO-1 being the most immunogenic among the family members. Hence, this review will focus on NY-ESO-1 and discuss the past and current NY-ESO-1 targeted immunotherapeutic strategies.

Expression and immunogenicity of NY-ESO-1 in colorectal cancer

Serum assays of NY-ESO-1 antibodies provide a guide to discriminate between patients who suffer from different types of cancer. In the present study, the expression of NY-ESO-1 was detected with the aim to identify a novel tumor antigen in colorectal cancer (CRC). Sera were obtained from 89 healthy individuals and 236 patients with CRC with stage I, II, III and IV tumors. The NY-ESO-1 autoantibody levels were determined using an enzyme-linked immunosorbent assay. The mRNA and protein expression levels of NY-ESO-1 were detected using reverse transcription-polymerase chain reaction and immunohistochemistry, respectively, in 60 CRC and paired adjacent non-tumor tissues. NY-ESO-1 antibody was detected in 40 of the 236 (16.9%) patients with CRC. The NY-ESO-1 antibody combined with carcinoembryonic antigen enhanced the sensitivity, from 52.1 to 62.7%, of the diagnosis of CRC. The frequency of antibody positivity increased with the TNM cancer stage (8.8 vs. 28.3% in stages I+II and III+IV, respectively). The mRNA and protein expression levels of NY-ESO-1 were significantly higher in CRC tissue than in adjacent non-tumor tissue. In conclusion, NY-ESO-1 is frequently expressed in CRC with the capacity of inducing a humoral immune response in CRC patients, exhibiting the potential to be a promising biomarker for CRC.

Autoantibodies: Opportunities for Early Cancer Detection

Cancer cells can induce an immunological response resulting in the production of tumor-associated (TA) autoantibodies. These serum immunobiomarkers have been detected for a range of cancers at an early stage before the development of clinical symptoms. Their measurement is minimally invasive and cost effective using established technologies. TA autoantibodies are present in a clinically significant number of individuals and could supplement current screening modalities to aid early diagnosis of high-risk populations and assist the clinical management of patients. Here we review their production, discovery, and validation as biomarkers for cancer and their current and future potential as clinical tools.

Can killers be saviors?

Autoimmunity and cancer have a multifarious epidemiology. Often, it is because of an impaired genome, culminating in functional aberrations in the human system. Systemic lupus erythematosus (SLE) is a heterogeneous complex disease which ensues due to the failure of the immune system to distinguish between self and non-self antigens, thus producing autoantibodies against DNA, RNA and proteins. Cancer, the other side of the same coin, results from an excessive proliferation of cells that evade immune regulation as a result of incompetent defense by T-cells, B-cells and macrophages. Recent findings have indicated that lupus autoantibodies could be used as an effective weapon to kill cancerous cells. This is an attempt to take an account of malicious 'lupus autoantibodies' and their role in neutralizing cancerous cells which may help in enhancing the survival rate of cancer patients, hence, killers can be saviors.

Building the Evidence Base of Blood-Based Biomarkers for Early Detection of Cancer: A Rapid Systematic Mapping Review

BACKGROUND

The Early Cancer Detection Consortium is developing a blood-test to screen the general population for early identification of cancer, and has therefore conducted a systematic mapping review to identify blood-based biomarkers that could be used for early identification of cancer.

METHODS

A mapping review with a systematic approach was performed to identify biomarkers and establish their state of development. Comprehensive searches of electronic databases Medline, Embase, CINAHL, the Cochrane library and Biosis were conducted in May 2014 to obtain relevant literature on blood-based biomarkers for cancer detection in humans. Screening of retrieved titles and abstracts was performed using an iterative sifting process known as "data mining". All blood based biomarkers, their relevant properties and characteristics, and their corresponding references were entered into an inclusive database for further scrutiny by the Consortium, and subsequent selection of biomarkers for rapid review. This systematic review is registered with PROSPERO (no. CRD42014010827).

FINDINGS

The searches retrieved 19,724 records after duplicate removal. The data mining approach retrieved 3990 records (i.e. 20% of the original 19,724), which were considered for inclusion. A list of 814 potential blood-based biomarkers was generated from included studies. Clinical experts scrutinised the list to identify miss-classified and duplicate markers, also volunteering the names of biomarkers that may have been missed: no new markers were identified as a result. This resulted in a final list of 788 biomarkers.

INTERPRETATION

This study is the first to systematically and comprehensively map blood biomarkers for early detection of cancer. Use of this rapid systematic mapping approach found a broad range of relevant biomarkers allowing an evidence-based approach to identification of promising biomarkers for development of a blood-based cancer screening test in the general population.

Human Blood Autoantibodies in the Detection of Colorectal Cancer

Colorectal cancer (CRC) is the second most common malignancy in the western world. Early detection and diagnosis of all cancer types is vital to improved prognosis by enabling early treatment when tumours should be both resectable and curable. Sera from 3 different cohorts; 42 sera (21 CRC and 21 matched controls) from New York, USA, 200 sera from Pittsburgh, USA (100 CRC and 100 controls) and 20 sera from Dundee, UK (10 CRC and 10 controls) were tested against a panel of multiple tumour-associated antigens (TAAs) using an optimised multiplex microarray system. TAA specific IgG responses were interpolated against the internal IgG standard curve for each sample. Individual TAA specific responses were examined in each cohort to determine cutoffs for a robust initial scoring method to establish sensitivity and specificity. Sensitivity and specificity of combinations of TAAs provided good discrimination between cancer-positive and normal serum. The overall sensitivity and specificity of the sample sets tested against a panel of 32 TAAs were 61.1% and 80.9% respectively for 6 antigens; p53, AFP, K RAS, Annexin, RAF1 and NY-CO16. Furthermore, the observed sensitivity in Pittsburgh sample set in different clinical stages of CRC; stage I (n = 19), stage II (n = 40), stage III (n = 34) and stage IV (n = 6) was similar (73.6%, 75.0%, 73.5% and 83.3%, respectively), with similar levels of sensitivity for right and left sided CRC. We identified an antigen panel of sufficient sensitivity and specificity for early detection of CRC, based upon serum profiling of autoantibody response using a robust multiplex antigen microarray technology. This opens the possibility of a blood test for screening and detection of early colorectal cancer. However this panel will require further validation studies before they can be proposed for clinical practice.

NY-ESO-1 autoantibody as a tumor-specific biomarker for esophageal cancer: screening in 1969 patients with various cancers

BACKGROUND

Although serum NY-ESO-1 antibodies (s-NY-ESO-1-Abs) have been reported in patients with esophageal carcinoma, this assay system has not been used to study a large series of patients with various other cancers.

PATIENTS AND METHODS

Serum samples of 1969 cancer patients [esophageal cancer (n = 172), lung cancer (n = 269), hepatocellular carcinoma (n = 91), prostate cancer (n = 358), gastric cancer (n = 313), colorectal cancer (n = 262), breast cancer (n = 365)] and 74 healthy individuals were analyzed using an originally developed enzyme-linked immunosorbent assay system for s-NY-ESO-1-Abs. The optical density cut-off value, determined as the mean plus three standard deviations for serum samples from the healthy controls, was fixed at 0.165. Conventional tumor markers were also evaluated in patients with esophageal carcinoma.

RESULTS

The positive rate of s-NY-ESO-1-Abs in patients with esophageal cancer (31 %) was significantly higher than that in the other groups: patients with lung cancer (13 %), patients with hepatocellular carcinoma (11 %), patients with prostate cancer (10 %), patients with gastric cancer (10 %), patients with colorectal cancer (8 %), patients with breast cancer (7 %), and healthy controls (0 %). The positive rate of s-NY-ESO-1-Abs was comparable to that of serum p53 antibodies (33 %), squamous cell carcinoma antigen (36 %), carcinoembryonic antigen (26 %), and CYFRA 21-1 (18 %) and gradually increased with the tumor stage.

CONCLUSIONS

The positive rate of s-NY-ESO-1-Abs was significantly higher in patients with esophageal cancer than in patients with the other types of cancers. On the basis of its high specificity and sensitivity, even in patients with stage I tumors, s-NY-ESO-1-Abs may be one of the first choices for esophageal cancer.

Sensitive Multiplexed Quantitative Analysis of Autoantibodies to Cancer Antigens with Chemically S-Cationized Full-Length and Water-Soluble Denatured Proteins

Humoral immune responses against tumor-associated antigens (TAAs) or cancer/testis antigens (CTAs) aberrantly expressed in tumor cells are frequently observed in cancer patients. Recent clinical studies have elucidated that anticancer immune responses with increased levels of anti-TAA/CTA antibodies improve cancer survival rates. Thus, these antibody levels are promising biomarkers for diagnosing the efficiency of cancer immunotherapy. Full-length antigens are favored for detecting anti-TAA/CTA antibodies because candidate antigen proteins contain multiple epitopes throughout their structures. In this study, we developed a methodology to prepare purified water-soluble and full-length antigens by using cysteine sulfhydryl group cationization (S-cationization) chemistry. S-Cationized antigens can be prepared from bacterial inclusion bodies, and they exhibit improved protein solubility but preserved antigenicity. Anti-TAA/CTA antibodies detected in cancer patients appeared to recognize linear epitopes, as well as conformational epitopes, and because the frequency of cysteine side-residues on the epitope-paratope interface was low, any adverse effects of S-cationization were virtually negligible for antibody binding. Furthermore, S-cationized antigen-immobilized Luminex beads could be successfully used in highly sensitive quantitative-multiplexed assays. Indeed, patients with a more broadly induced serum anti-TAA/CTA antibody level showed improved progression-free survival after immunotherapy. The comprehensive anti-TAA/CTA assay system, which uses S-cationized full-length and water-soluble recombinant antigens, may be a useful diagnostic tool for assessing the efficiency of cancer immunotherapy.

Autoantibodies against tumor-associated antigens for detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide. The survival rate after the onset of symptoms is generally less than one year for the late presentation of HCC, and reliable tools for early diagnosis are lacking. Therefore, novel biomarkers for the early detection of HCC are urgently required. Recent studies show that the abnormal release of proteins by tumor cells can elicit humoral immune responses to self-antigens called tumor-associated antigens (TAAs). The corresponding autoantibodies can be detected before the clinical diagnosis of cancer. Therefore, there is growing interest in using serum autoantibodies as cancer biomarkers. In this review, we focus on the advances in research on autoantibodies against TAAs as serum biomarker for detection of HCC, the mechanism of the production of TAAs, and the association of autoantibodies with patients’ clinical characteristics.