Sensitive Blood-Based Detection of Asbestos-Associated Diseases Using Cysteine-Rich Angiogenic Inducer 61 as Circulating Protein Biomarker

Cancer Screening Companies Are Rapidly Proliferating: Are They Ready for Business?

Cancer screening has been a major research front for decades. The classical circulating biomarkers for cancer (such as PSA, CEA, CA125, AFP, etc.) are neither sensitive nor specific and are not recommended for population screening. Recently, circulating tumor DNA (ctDNA) emerged as a new pan-cancer tumor marker, with much promise for clinical applicability. ctDNA released by tumor cells can be used as a proxy of the tumor burden and molecular composition. It has been hypothesized that if ctDNA is extracted from plasma and analyzed for genetic changes, it may form the basis for a non-invasive cancer detection test. Lately, there has been a proliferation of "for-profit" companies that will soon offer cancer screening services. Here, we comment on Grail, Thrive, Guardant, Delfi, and Freenome. Previously, we identified some fundamental difficulties associated with this new technology. In addition, clinical trials are exclusively case-control studies. The sensitivities/specificities/predictive values of the new screening tests have not been well-defined or, the literature-reported values are rather poor. Despite these deficiencies some of the aforementioned companies are already testing patients. We predict that the premature use of ctDNA as a cancer screening tool may add another disappointment in the long history of this field.

Blood-based detection of lung cancer using cysteine-rich angiogenic inducer 61 (CYR61) as a circulating protein biomarker: a pilot study

Lung cancer is the most often diagnosed cancer and the main cause of cancer deaths in the world compared with other tumor entities. To date, the only screening method for high‐risk lung cancer patients is low‐dosed computed tomography which still suffers from high false‐positive rates and overdiagnosis. Therefore, there is an obvious need to identify biomarkers for the detection of lung cancer that could be used to guide the use of low‐dosed computed tomography or other imaging procedures. We aimed to assess the performance of the protein cysteine‐rich angiogenic inducer 61 (CYR61) as a circulating biomarker for the detection of lung cancer. CYR61 concentrations in plasma were significantly elevated in 87 lung cancer patients (13.7 ± 18.6 ng·mL⁻¹) compared with 150 healthy controls (0.29 ± 0.22 ng·mL⁻¹). Subset analysis stratified by sex revealed increased CYR61 concentrations for adenocarcinoma and squamous cell carcinoma in men compared with women. For male lung cancer patients versus male healthy controls, the sensitivity was 84% at a specificity of 100%, whereas for females, the sensitivity was 27% at a specificity of 99%. The determination of circulating CYR61 protein in plasma might improve the detection of lung cancer in men. The findings of this pilot study support further verification of CYR61 as a biomarker for lung cancer detection in men. Additionally, CYR61 is significantly elevated in women but sensitivity and specificity for CYR61 are too low for the improvement of the detection of lung cancer in women.

Circulating Cellular Communication Network Factor 1 Protein as a Sensitive Liquid Biopsy Marker for Early Detection of Breast Cancer

BACKGROUND

Despite recent progress in liquid biopsy technologies, early blood-based detection of breast cancer is still a challenge.

METHODS

We analyzed secretion of the protein cellular communication network factor 1 (CCN1, formerly cysteine-rich angiogenic inducer 61) in breast cancer cell lines by an enzyme-linked immunosorbent assay (ELISA). Soluble CCN1 in the plasma (2.5 µL) of 544 patients with breast cancer and 427 healthy controls was analyzed by ELISA. The breast cancer samples were acquired at the time of primary diagnosis prior to neoadjuvant therapy or surgery. A classifier was established on a training cohort of patients with breast cancer and age-adapted healthy controls and further validated on an independent cohort comprising breast cancer patients and healthy controls. Samples from patients with benign breast diseases were investigated as additional controls. Samples from patients with acute heart diseases (n = 127) were investigated as noncancer controls. The diagnostic accuracy was determined by receiver operating characteristic using the parameters area under the curve, sensitivity, and specificity.

RESULTS

CCN1 was frequently secreted by breast cancer cell lines into the extracellular space. Subsequent analysis of clinical blood samples from patients with breast cancer and age-adjusted healthy controls revealed an overall specificity of 99.0% and sensitivity of 80.0% for cancer detection. Remarkably, 81.5% of small T1 cancers were already CCN1-positive, while CCN1 concentrations in patients with benign breast lesions were below the threshold for breast cancer detection.

CONCLUSIONS

Circulating CCN1 is a potentially novel blood biomarker for the detection of breast cancer at the earliest invasive stage.