Discovering Panel of Autoantibodies for Early Detection of Lung Cancer Based on Focused Protein Array

Substantial studies indicate that autoantibodies to tumor-associated antigens (TAAbs) arise in early stage of lung cancer (LC). However, since single TAAbs as non-invasive biomarkers reveal low diagnostic performances, a panel approach is needed to provide more clues for early detection of LC. In the present research, potential TAAbs were screened in 150 serum samples by focused protein array based on 154 proteins encoded by cancer driver genes. Indirect enzyme-linked immunosorbent assay (ELISA) was used to verify and validate TAAbs in two independent datasets with 1,054 participants (310 in verification cohort, 744 in validation cohort). In both verification and validation cohorts, eight TAAbs were higher in serum of LC patients compared with normal controls. Moreover, diagnostic models were built and evaluated in the training set and the test set of validation cohort by six data mining methods. In contrast to the other five models, the decision tree (DT) model containing seven TAAbs (TP53, NPM1, FGFR2, PIK3CA, GNA11, HIST1H3B, and TSC1), built in the training set, yielded the highest diagnostic value with the area under the receiver operating characteristic curve (AUC) of 0.897, the sensitivity of 94.4% and the specificity of 84.9%. The model was further assessed in the test set and exhibited an AUC of 0.838 with the sensitivity of 89.4% and the specificity of 78.2%. Interestingly, the accuracies of this model in both early and advanced stage were close to 90%, much more effective than that of single TAAbs. Protein array based on cancer driver genes is effective in screening and discovering potential TAAbs of LC. The TAAbs panel with TP53, NPM1, FGFR2, PIK3CA, GNA11, HIST1H3B, and TSC1 is excellent in early detection of LC, and they might be new target in LC immunotherapy.

Autoantibodies as biomarkers for colorectal cancer: A systematic review, meta-analysis, and bioinformatics analysis

Colorectal cancer is a very common cancer worldwide. Serum tumor-associated autoantibodies (TAAbs), especially the anti-p53 autoantibody, may be promising biomarkers to detect early-stage colorectal cancer. This study aimed to identify all known autoantibodies and their value in colorectal cancer diagnosis, as well as exploring the underlying connections and mechanisms through a bioinformatics analysis. Databases were used to select available articles of TAAbs in colorectal cancer. In a meta-analysis of the anti-p53 autoantibody, the diagnostic odds ratio and area under the curve (AUC) of the summary receiver-operating characteristic (SROC) curve were calculated using Stata 12.0 and Meta-Disc 1.4. We identified 73 articles including 199 single autoantibodies and 42 multiple autoantibodies. The maximum value of Youden's index was 0.76, combining c-MYC, p53, cyclin B1, p62, Koc, IMP1, and survivin. The diagnostic odds ratio for anti-p53 autoantibody at all stages was 10.86 (95% CI 8.40, 14.06) with low heterogeneity (I² = 40.3%) and the AUC of the SROC curve was 0.82. For the anti-p53 autoantibody in early-stage colorectal cancer, the diagnostic odds ratio was 4.82 (95% CI 2.95, 7.87) with heterogeneity (I² = 7.9%) and the AUC of the SROC curve was 0.72. Eighty-seven autoantibodies were selected for bioinformatics analyses. We found that the most enriched functional terms and protein-protein interactions may relate to the mechanism of autoantibody generation. In summary, our study summarized the diagnostic value of TAAbs in colorectal cancer, either as single molecules or in combination. Bioinformatics analyses may be a new approach to explore the mechanism of autoantibody generation.

Immunohistochemical expression and serum level of survivin protein in colorectal cancer patients

Survivin is one of the apoptosis-related inhibitors that is associated with a more aggressive behavior and a poor prognosis in numerous types of malignancies, including colorectal cancer (CRC). The objective of the present study was to perform immunohistochemical tissue analysis of survivin expression and serum analysis of survivin levels in CRC patients. The study group consisted of 55 CRC patients. Survivin expression was assessed by immunohistochemistry in 38 patients using monoclonal antibodies. Color reactions were observed in the nucleus and cytoplasm of the cancer cells. The expression was defined based on the H-score method. The level of survivin was determined using the enzyme-linked immunosorbent assay method. A positive immunoreaction was observed in the tumor tissues of 84.2% (32/38) of patients with CRC, consisting of nuclear (63.2%; 24/38) and cytoplasmic (81.6%; 31/38) expression. The survivin nuclear expression was associated with tumor mass location and the presence of distant metastases (P=0.048 and P=0.026, respectively). Survivin was detected in the sera of 38.2% (21/55) of CRC patients and in 81.8% (18/22) of healthy individuals. Serum protein levels were found to correlate with hematocrit (P=0.035), hemoglobin (P=0.008) and albumin (P=0.045), but not with any of the investigated clinicopathological parameters. The immunohistochemical positive reaction of survivin in the nuclei of cancer cells may condition their proliferative capacity, which is associated with higher risk of developing metastatic foci. Thus, the present study suggests that the expression of survivin may have diagnostic implications in cancer of the colon and thus requires further research. By contrast, the survivin serum level in CRC patients appears to be diagnostically ineffectual for clinical use.

The potential role of immunotherapy to treat colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is the fourth most common cancer and the second leading cause of cancer-related death worldwide. Surgery, chemotherapy, radiation therapy and anti-angiogenic therapies form the backbone of treatment for CRC in various stages. Immunotherapy is frequently used either alone or in combination with chemotherapy for the treatment of various cancers such as melanoma, prostate cancer and renal cell cancer. Current CRC research is moving forward to discover ways to incorporate immunotherapies into the treatment of CRC.

AREAS COVERED

The aim of this review is to summarize the potential role of immunotherapy in CRC. Herein, the authors provide a brief overview of immune modulatory cells, immune surveillance and escape in CRC. They also review vaccine trials in addition to cytokines and monoclonal antibodies. This coverage includes ongoing trials and checkpoint inhibitors such as cytotoxic T lymphocyte antigen-1, programmed cell death-1, and PDL1.

EXPERT OPINION

Checkpoint inhibitors in combination with either chemotherapy or chemo-antiangiogenic-therapy may represent a future therapeutic approach for CRC incorporating immune system targeting. Given the success of immune-based therapy in other tumor types, the authors anticipate that a similar breakthrough in CRC will be forthcoming.