Preclinical and dose-ranging assessment of hESC-derived dopaminergic progenitors for a clinical trial on Parkinson's disease.

Human embryonic stem cell (hESC)-derived midbrain dopaminergic (mDA) cell transplantation is a promising therapeutic strategy for Parkinson's disease (PD). Here, we present the derivation of high-purity mDA progenitors from clinical-grade hESCs on a large scale under rigorous good manufacturing practice (GMP) conditions. We also assessed the toxicity, biodistribution, and tumorigenicity of these cells in immunodeficient rats in good laboratory practice (GLP)-compliant facilities. Various doses of mDA progenitors were transplanted into hemi-parkinsonian rats, and a significant dose-dependent behavioral improvement was observed with a minimal effective dose range of 5,000-10,000 mDA progenitor cells. These results provided insights into determining a low cell dosage (3.15 million cells) for human clinical trials. Based on these results, approval for a phase 1/2a clinical trial for PD cell therapy was obtained from the Ministry of Food and Drug Safety in Korea, and a clinical trial for treating patients with PD has commenced.

HAUSP stabilizes Cdc25A and protects cervical cancer cells from DNA damage response.

Resistance to DNA-damaging agents is one of the main reasons for the low survival of cervical cancer patients. Previous reports have suggested that the Cdc25A oncoprotein significantly affects the level of susceptibility to DNA-damaging agents, but the molecular mechanism remains unclear. In this study, we used Western blot and flow cytometry analyses to demonstrate that the deubiquitinating enzyme HAUSP stabilizes Cdc25A protein level. Furthermore, in a co-immunoprecipitation assay, we found that HAUSP interacts with and deubiquitinates Cdc25A both exogenously and endogenously. HAUSP extends the half-life of the Cdc25A protein by circumventing turnover. HAUSP knockout in HeLa cells using the CRISPR/Cas9 system caused a significant delay in Cdc25A-mediated cell cycle progression, cell migration, and colony formation and attenuated tumor progression in a mouse xenograft model. Furthermore, HAUSP-mediated stabilization of the Cdc25A protein produced enhanced resistance to DNA-damaging agents. Overall, our study suggests that targeting Cdc25A and HAUSP could be a promising combinatorial approach to halt progression and minimize antineoplastic resistance in cervical cancer.