Diagnostic efficacy of the new prospective biomarker's combination CA 15-3 and CA-62 for early-stage breast cancer detection: Results of the blind prospective-retrospective clinical study.

BACKGROUND: Combination of different cancer markers is often used for predicting tumor growth, for the response to cancer therapy, and for increase in the positive diagnosis ratio in the malignant tumors. OBJECTIVE: Evaluation of the diagnostic efficacy of CA 15-3 and CA-62 cancer markers combination for early stages of breast cancer (BC) detection. METHODS: This blind study was performed on 2 clinically validated Sets that included serum measurements of CA 15-3 ELISA and CLIA-CA-62 assays in 488 serum samples with TNM classification. A study included 300 BC patients (254 at Stages I and II, 20 with ductal carcinoma in situ (DCIS), and 26 Stages III and IV patients), 47 patients with breast benign diseases, and 141 healthy controls. RESULTS: Sensitivity for DCIS & Stage I breast cancer detection was 75% at 100% Specificity (AUC = 0.895) using a following combination of two antigens: 10 < CA15-3 < 46 U/ml and CA-62 ⩾ 6300 U/ml, which allows eliminating false positive results. CONCLUSIONS: The results obtained in a blind study demonstrate that a combination of CA15-3 with CA-62 yields 75% Sensitivity at 100% Specificity for DCIS and Stage I breast cancer detection, which has a potential to be integrated into existing screening programs.

Binding characterization of the targeting drug AIMPILA to AFP receptors in human tumor xenografts.

The main objective of this study was the characterization of preclinical tumor models based on their expression of alpha-fetoprotein receptor (RECAF) for targeting cancer cells with a new non-covalent complex (AIMPILA) containing alpha-fetoprotein as the carrier and Atractyloside as an apoptosis-inducing agent. For that purpose, we measured the amount of RECAF in the homogenates of the grafted tumors T47D and SW620 and in HepG2 cell extracts. We also determined the alpha-fetoprotein binding specificity of the targeting drug AIMPILA using a solid-phase chemiluminescent assay with AIMPILA-Acrdidinium. We found that RECAF is practically absent from healthy mice tissues (100 Units/mg) where in malignant cells, the amount of alpha-fetoprotein receptors follows this order: T47D (9152 Units/mg) > HepG2 (4865 Units/mg) > SW620 (2839 Units/mg). This agrees with our findings regarding AIMPILA-induced tumor growth inhibition (T47D (T/C = 22%) > HepG2 (T/C = 51%) > SW620 (T/C = 70%), where T/C is the ratio of tumor volume in treated vs control animals). Our results demonstrate that the therapeutic response to the targeting drug AIMPILA strongly depends on the RECAF expression by human tumors and confirms the choice of the tumor models used for an AIMPILA preclinical study.

Combination of CA125 and RECAF biomarkers for early detection of ovarian cancer.

Ovarian cancer can be cured in up to 90% of cases if diagnosed early. CA125, the most studied ovarian cancer biomarker, exhibits poor sensitivity for detecting early disease stages and low specificity to malignancy. RECAF, the alpha-fetoprotein receptor, is a wide-spectrum oncofetal antigen with clinical potential for cancer diagnosis, screening, and monitoring. This study evaluated the performance of RECAF as a diagnostic tool and the sensitivity of a combination of RECAF and CA125 to detect early stages of ovarian cancer at a cutoff resulting in 100% specificity among healthy women. This retrospective case-control study was designed to measure the serum levels of RECAF and CA125 in normal individuals (n=106) and cancer patients stages I/II (RECAF, n=32; CA125, n=35) and III/IV (RECAF, n=49; CA125, n=51). A competitive chemiluminescence assay was developed to measure the circulating RECAF. To eliminate any false positives, we classified as positive any patient with a RECAF or a CA125 value higher than their respective 100% specificity cutoff. We have shown that RECAF discriminated cancer and healthy donors better than CA125, particularly in the early stages (AUC(RECAF)=0.96 and AUC(CA125)=0.805). CA125 sensitivity was lower in the early stages than in the advance stages; RECAF sensitivity was high at all stages. A combination of CA125 and RECAF detected three out of four early-stage patients, with no false positives. In conclusion, the combination of RECAF and CA125 serum values provides the specificity and the sensitivity necessary to screen for ovarian cancer and in particular, to detect early stages of the disease.

Jel44 monoclonal Fab fragment specific for HPr of the phosphoenolpyruvate:sugar phosphotransferase system of Escherichia coli and the complex of Jel44 Fab fragment with HPr: preparation, crystallization and preliminary crystallographic analysis.

Jel44 is a mouse monoclonal antibody specific for the histidine-containing phosphocarrier protein (HPr), a component of a sugar-transport system in Escherichia coli. Because Jel44 binding to HPr is dependent upon ionic strength and the enthalpic and entropic contributions do not vary over the temperature range 277-310 K, the complex is of great interest. A single crystal of the Jel44 Fab fragment was obtained and diffracted X-rays to a maximum resolution of 4.6 A on an in-house X-ray source. The crystal belongs to space group P2(1), with unit-cell parameters a = 68.6, b = 67.7, c = 105.5 A, beta = 96 degrees. Although crystals of the complex of Jel44 Fab fragment with HPr could not be fully characterized owing to suspected crystal twinning, it was encouraging that they diffracted X-rays to 2.5 A on an in-house X-ray source. It is thus foreseen that improvement of crystal quality will allow the complete solution of this novel structure.