Tumour cells apoptosis factor (Immune System Key)

We report the isolation of a novel Tumor-Cells Apoptosis Factor (Nerofe). We found that cDNA of this protein is expressed mainly in the human thymus and partially in the colon and in the frontal lobe of brain. Immunohistochemical studies localize Tumor-Cells Apoptosis Factor (TCApF) to the medulla and Hassal's corpuscles of the thymus gland, which are responsible for negative selection. Treatment of mice with induced AML terminates the cancer development and completely eliminates metastatic cell colonies from the bone marrow and the spleen that reduces probability of the cancer return. We find that TCApF binds to the T1/ST2 receptor and activates caspases 8, 9 and 3 mediated apoptosis, together with activation of JNKinase and p38 MAPKinase. Application of TCApF to cells induced apoptosis in acute myeloid leukemia proliferating cells (U937 premeyloid cells), in human breast carcinoma (MCF7), human glioblastoma, human neuroblastoma, human prostate cancer and human lung cancer proliferating cells. In contrast, TCApF was unable to induce apoptosis in non-proliferating cells. The selectivity of TCApF-induced apoptosis is related to the level of T1/ST2 receptor expression. This is the first report linking the T1/ST2 receptor to apoptosis.

The aim of the present phase I first-in-human study was to investigate the safety/efficacy of dTCApFs (a novel hormone peptide that enters cells through the T1/ST2 receptor), in advanced/metastatic solid tumors. The primary objective of this open-label dose-escalation study was to determine the safety profile of dTCApFs. The study enrolled patients (aged ≥18 years) with pathologically confirmed locally advanced/metastatic solid malignancies, who experienced treatment failure or were unable to tolerate previous standard therapy. The study included 17 patients (64% male; median age, 65 years; 47% colorectal cancer, 29% pancreatic cancer). The patients received 1-3 cycles of escalating dTCApFs doses (6-96 mg/m²). The mean number ± standard deviation of treatment cycles/patient was 3.2±1.4; no dose-limiting toxicities were observed up to a dose of 96 mg/m², and the maximum tolerated dose was not reached. Half-life, maximal plasma concentration, and dTCApFs exposure were found to be linearly correlated with dose. Five patients were treated for ≥3 months (12, 24, 48 mg/m²) and experienced stable disease throughout the treatment period, and 1 experienced pathological complete response. Analysis of serum biomarkers revealed decreased levels of angiogenic factors at dTCApFs concentrations of 12-48 mg/m², increased levels of anticancer cytokines, and induction of the endoplasmic reticulum (ER) stress biomarker GRP78/BiP. Efficacy and biomarker data suggest that patients whose tumors were T1/ST2-positive exhibited a better response to dTCApFs. In conclusion, dTCApFs was found to be safe/well-tolerated, and potentially efficacious, with linear pharmacokinetics. Consistent with preclinical studies, the mechanism through which dTCApFs exerts anticancer effects appears to involve induction of ER stress, suppression of angiogenesis, and activation of the innate immune response. However, further studies are warranted.