Blood-Based Protein Biomarker Panel for the Detection of Colorectal Cancer

Blood-Based Protein Biomarker Panel for the Detection of Colorectal Cancer

The majority of colorectal cancer (CRC) cases are preventable by early detection and removal of precancerous polyps. Even though CRC is the second most common internal cancer in Australia, only 30 per cent of the population considered to have risk factors participate in stool-based test screening programs. Evidence indicates a robust, blood-based, diagnostic assay would increase screening compliance. A number of potential diagnostic bloodbased protein biomarkers for CRC have been reported, but all lack sensitivity or specificity for use as a stand-alone diagnostic. The aim of this study was to identify and validate a panel of protein-based biomarkers in independent cohorts that could be translated to a reliable, non-invasive blood-based screening test.
Serum Tumor Markers in Colorectal Cancer – Staging, Grading and Follow-Up

Serum Tumor Markers in Colorectal Cancer – Staging, Grading and Follow-Up

Early diagnosis of colorectal cancer, a frequent neoplasia in industrialized countries, permits curative surgery. In this study we assessed the clinical role of serum tumor markers determination in diagnosing, staging, and grading colorectal cancer; the role of carcinoembryonic antigen (CEA), CA 19-9, tissue polypeptide antigen (TPA) and CA 72-4 in colorectal cancer follow-up was also assessed. In 114 patients with colorectal cancer, the oncofetal antigen CEA was compared with the membrane-associated glycoproteins CA 19-9, CA 242, and CA 72-4 and with the cytokeratins TPA, tissue polypeptide-specific antigen (TPS) and tissue polypeptide monoclonal antigen (TPM). Overall, the most sensitive indices were TPA and TPS (67% and 7096, respectively). Tumor stage influenced the levels of CEA, CA 19-9, and TPA, but not those of TPS, while tumor grade influenced CEA and TPS, but not CA 72-4, TPA, and TPM. TPA was the most sensitive index in identifying early or well-differentiated colorectal cancers. The sensitivity was enhanced when this marker was determined in combination with CEA, in diagnosing both advanced and early colorectal tumors. Seventy-seven patients were followed up after therapy for at least 18 months. CEA was the most sensitive index of recurrence (58%); however, this sensitivity is too low to consider tumor markers useful in colorectal cancer follow-up.
Comparison and Evaluation of 92 Plasma Protein Biomarkers for Early Detection of Colorectal Cancer

Comparison and Evaluation of 92 Plasma Protein Biomarkers for Early Detection of Colorectal Cancer

Novel noninvasive blood-based screening tests are strongly desirable for early detection of colorectal cancer. We aimed to conduct a head-to-head comparison of the diagnostic performance of 92 plasma-based tumor-associated protein biomarkers for early detection of colorectal cancer in a true screening setting. Among all available 35 carriers of colorectal cancer and a representative sample of 54 men and women free of colorectal neoplasms recruited in a cohort of screening colonoscopy participants in 2005–2012 (N ¼ 5,516), the plasma levels of 92 protein biomarkers were measured. ROC analyses were conducted to evaluate the diagnostic performance. A multimarker algorithm was developed through the Lasso logistic regression model and validated in an independent validation set. The .632þ bootstrap method was used to adjust for the potential overestimation of diagnostic performance. Seventeen protein markers were identified to show statistically significant differences in plasma levels between colorectal cancer cases and controls. The adjusted area under the ROC curves (AUC) of these 17 individual markers ranged from 0.55 to 0.70. An eight-marker classifier was constructed that increased the adjusted AUC to 0.77 [95% confidence interval (CI), 0.59–0.91]. When validating this algorithm in an independent validation set, the AUC was 0.76 (95% CI, 0.65–0.85), and sensitivities at cutoff levels yielding 80% and 90% specificities were 65% (95% CI, 41–80%) and 44% (95% CI, 24–72%), respectively. The identified profile of protein biomarkers could contribute to the development of a powerful multimarker blood-based test for early detection of colorectal cancer.
Biomarkers for Early Detection of CRC – Risk versus Early Detection

Biomarkers for Early Detection of CRC – Risk versus Early Detection

There is an increasing demand for biomarkers in colon cancer for risk assessment, early detection, prognosis, and surrogate end points. A number of biomarkers have been identified for early detection of colon cancer, although the risk factors have not been identified extensively. The major advances in understanding colorectal cancer include the identification and the involvement of APC, p53, and Ki-ras in the development and progression of the disease, the identification of the aberrant crypt foci as an early preinvasive lesion, and its relation to the development of cancer. Detecting malignant neoplasms in the early stages offers clinical advantages; therefore, the National Cancer Institute has established an Early Detection Research Network. The emphasis of the network is on translational research and collaboration among scientists.
Combined assays for serum CEA and mRNA-17-3p in Dx for Stage I and II Colorectal Cancer

Combined assays for serum CEA and mRNA-17-3p in Dx for Stage I and II Colorectal Cancer

Colorectal cancer is among the leading causes of cancer-related mortality, one of the main reasons for which is the lack of an effective screening method for early-stage disease. The levels of carcinoembryonic antigen (CEA) and microRNA (miR)-17-3p in the serum of 70 patients with stage I̸II colon cancer and 70 healthy volunteers were determined, and the diagnostic value of CEA plus miR-17-3p detection for colon cancer was assessed. The levels of CEA were measured by a radioimmunoassay method, and those of miR-17-3p using the reverse transcription-quantitative polymerase chain reaction method. miR-16 was used as the endogenous control, as it displayed high stability, high abundance and low variability in the analyzed serum samples. The receiver operating characteristic (ROC) curve analysis indicated the potential diagnostic value of the two markers and the area under the ROC curve (AUC) for CEA and miR-17-3p was 0.719 (95% CI: 0.658-0.843) and 0.807 (95% CI: 0.748-0.906), respectively. At a threshold of 9.6 ng/ml for CEA, the optimal sensitivity and specificity were 74.6 and 84.3%, respectively, in discriminating colon cancer patients from healthy controls. At a threshold of 2.98 for miR-17-3p, the sensitivity and the specificity were 83.6 and 72.9%, respectively. A combined ROC analysis using CEA and miR-17-3p revealed an AUC of 0.929 (95% CI: 0.834-0.978) with a sensitivity of 96.4% and a specificity of 95.7% in discriminating colon cancer patients from healthy controls. In conclusion, both CEA and miR-17-3p were highly expressed in the serum of our series of colon cancer patients. CEA plus miR-17-3p detection significantly increased the sensitivity and specificity in discriminating stage I/II colon cancer patients from healthy controls. Therefore, combined detection of serum CEA and miR-17-3p levels may have the potential to become a new laboratory method for the early clinical diagnosis of colon cancer.
Tumor Markers for Gastrointestinal Cancers

Tumor Markers for Gastrointestinal Cancers

A tumor marker is a substance found in a person's blood, urine, or the tumor itself. It is produced by the tumor or the body in response to cancer, or a noncancerous condition, such as inflammation. Your doctor may suggest tumor marker tests at various stages in the diagnosis and treatment of cancer. When used with other medical tests, a tumor marker test can provide helpful information about the cancer and its treatment.
Dx value of CEA and CA 19.9 in Colorectal Cancer

Dx value of CEA and CA 19.9 in Colorectal Cancer

The purpose of this study was to evaluate the diagnostic efficiency of colorectal carcinoma (CRC) with the tumor markers Carcinoembryonic Antigen (CEA) and Carbohydrate Antigen 19-9 (CA 19-9), in addition to investigating whether CA 19-9 can be used to screen the disease process in patients with CRC who had no elevation of CEA levels. Serum levels of CEA and CA 19-9 were measured in: 138 patients with CRC; 111 patients with benign colorectal diseases. The diagnostic value was performed using the logistic regression equation and receiver operating characteristic curves (ROC). The serum levels of CEA and CA 19-9 in the patients with CRC were significantly higher than those in the patients with benign colorectal diseases (P < 0.001). Receiver operating characteristic curves (ROC) in the patients with CRC versus those with benign colorectal disease yielded the optimal cut-off value of 3.36 ng/ml for CEA and 23.9 U/ml for CA 19-9, respectively. The area under ROC curve (AUC) was 0.789 for CEA, 0.690 for CA 19-9 and 0.900 for the combination of the two tumor markers. The combination resulted in a higher Youden index and a sensitivity of 85.3%. The combined detection of serum CEA and CA 19-9 could play a pivotal role in the diagnosis of CRC, and could drastically improve the sensitivity for the diagnosis of CRC. CA 19-9 might be a tumor biomarker in addition to CEA for CRC.
Blood Markers for Early Detection of Colorectal Cancer – A systematic Review

Blood Markers for Early Detection of Colorectal Cancer – A systematic Review

Despite different available methods for colorectal cancer (CRC) screening and their proven benefits, morbidity, and mortality of this malignancy are still high, partly due to lowcompliance with screening. Minimally invasive tests based on the analysis of blood specimens may overcome this problem. The purpose of this reviewwas to give an overviewof published studies on blood markers aimed at the early detection of CRC and to summarize their performance characteristics. The PUBMED database was searched for relevant studies published until June 2006. Only studies with more than 20 cases and more than 20 controls were included. Information on the markers under study, on the underlying study populations, and on performance characteristics was extracted. Special attention was given to performance characteristics by tumor stage. Overall, 93 studies evaluating 70 different markers were included. Most studies were done on protein markers, but DNA markers and RNA markers were also investigated. Performance characteristics varied widely between different markers, but also between different studies using the same marker. Promising results were reported for some novel assays, e.g., assays based on SELDI-TOF MS or MALDI-TOF MS, for some proteins (e.g., soluble CD26 and bone sialoprotein) and also for some genetic assays (e.g., L6 mRNA), but evidence thus far is restricted to single studies with limited sample size and without further external validation. Larger prospective studies using study populations representing a screening population are needed to verify promising results. In addition, future studies should pay increased attention to the potential of detecting precursor lesions.
Discovery and Validation of New Potential Biomarkers for Early Detection of Colorectal Cancer

Discovery and Validation of New Potential Biomarkers for Early Detection of Colorectal Cancer

Accurate detection of characteristic proteins secreted by colon cancer tumor cells in biological fluids could serve as a biomarker for the disease. The aim of the present study was to identify and validate new serum biomarkers and demonstrate their potential usefulness for early diagnosis of colon cancer. The study was organized in three sequential phases: 1) biomarker discovery, 2) technical and biological validation, and 3) proof of concept to test the potential clinical use of selected biomarkers. A prioritized subset of the differentially expressed genes between tissue types (50 colon mucosa from cancer-free individuals and 100 normal-tumor pairs from colon cancer patients) was validated and further tested in a series of serum samples from 80 colon cancer cases, 23 patients with adenoma and 77 cancer-free controls. In the discovery phase, 505 unique candidate biomarkers were identified, with highly significant results and high capacity to discriminate between the different tissue types. After a subsequent prioritization, all tested genes (N = 23) were successfully validated in tissue, and one of them, COL10A1, showed relevant differences in serum protein levels between controls, patients with adenoma (p = 0.0083) and colon cancer cases (p = 3.2e-6). We present a sequential process for the identification and further validation of biomarkers for early detection of colon cancer that identifies COL10A1 protein levels in serum as a potential diagnostic candidate to detect both adenoma lesions and tumor.
Serum sHLA-G levels as a useful indicator in distinguishing Colorectal Cancer

Serum sHLA-G levels as a useful indicator in distinguishing Colorectal Cancer

Soluble human leukocyte antigen-G (sHLA-G) has been reported in malignancies and is implicated in mediating immune surveillance of tumor. The aim of our study is to detect serum sHLA-G levels in colorectal cancer and to determine whether sHLA-G may be helpful in distinguishing colorectal cancer from benign colorectal diseases. Serum sHLA-G levels were determined using enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) curve was used to evaluate the feasibility of sHLA-G in differentiating colorectal cancer from benign colorectal diseases. Median sHLA-G concentrations were significantly higher in colorectal cancer compared to normal colorectum, hyperplastic polyp, inflammatory bowel disease and adenoma (all at p < 0.001, respectively). ROC curve for sHLA-G revealed an area under the curve of 84.2%, and when 88.6 U/mL was used as cutoff, a sensitivity of 72.2% and a specificity of 87.8% were achieved. Comparison of sHLA-G and carcinoembryogenic antigen ROC curves indicated that sHLA-G was superior to CEA in differentiating colorectal cancer from benign colorectal diseases (p < 0.001). ROC curves analysis of the combined sHLA-G and CEA showed a higher detection capacity (area under the ROC curve, 87.4%) than that of markers considered singly. These findings reveal that serum levels of sHLA-G are significantly increased in colorectal cancer which may serve as a potent mediator of immune escape in colorectal cancer, and sHLA-G may be a useful indicator in differentiating colorectal cancer from benign colorectal diseases.