Single-cell metabolic fingerprints discover a cluster of circulating tumor cells with distinct metastatic potential.

Circulating tumor cells (CTCs) are recognized as direct seeds of metastasis. However, CTC count may not be the "best" indicator of metastatic risk because their heterogeneity is generally neglected. In this study, we develop a molecular typing system to predict colorectal cancer metastasis potential based on the metabolic fingerprints of single CTCs. After identification of the metabolites potentially related to metastasis using mass spectrometry-based untargeted metabolomics, setup of a home-built single-cell quantitative mass spectrometric platform for target metabolite analysis in individual CTCs and use of a machine learning method composed of non-negative matrix factorization and logistic regression, CTCs are divided into two subgroups, C1 and C2, based on a 4-metabolite fingerprint. Both in vitro and in vivo experiments demonstrate that CTC count in C2 subgroup is closely associated with metastasis incidence. This is an interesting report on the presence of a specific population of CTCs with distinct metastatic potential at the single-cell metabolite level.

Human umbilical cord-derived mesenchymal stem cells and human cord blood mononuclear cells protect against cisplatin-induced acute kidney injury in rat models.

Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) are a promising tool to attenuate cisplatin (CP)-induced acute kidney injury (AKI). However, whether the transplantation of human cord blood mononuclear cells (hCBMNCs) exhibits similar protective effects and their potential underlying mechanisms of action remain unclear. The present study aimed to determine the protective effects of hUCMSCs and hCBMNCs transplantation therapies on an established CP-induced rat model and explore their underlying mechanisms of action. A total of 24 Sprague-Dawley rats, selected based on body weight, were randomly assigned into 4 groups: i) normal control; ii) model (CP); iii) hCBMNCs (CP + hCBMNCs); and iv) hUCMSCs (CP + hUCMSCs). hUCMSCs (2.0x106 cells) and hCBMNCs (2.0x106 cells) were injected into the femoral vein of rats 24 h after CP (8 mg/kg) treatment. To determine the effects of hCBMNCs and hUCMSCs on CP-induced rats, renal function assessment and histological evaluations were performed. Expression levels of high mobility group box 1 (HMGB1) and the ratio of Bax/Bcl2 in renal tissues were detected to elucidate their underlying molecular mechanisms of action. The results demonstrated that transplantation of hUCMSCs and hCBMNCs significantly improved renal function in CP-induced AKI rats, as evidenced by the enhancement of renal morphology; decreased concentrations of blood urea nitrogen and serum creatinine; and a lower percentage of apoptotic renal tubular cells. The expression of HMGB1 and the ratio of Bax/Bcl-2 were significantly reduced in the hUCMSCs and hCBMNCs groups compared with CP group. In conclusion, the present study indicated that hCBMNCs exert similar protective effects to hUCMSCs on CP-induced AKI. hUCMSCs and hCBMNCs protect against CP-induced AKI by suppressing HMGB1 expression and preventing cell apoptosis.

Conversion of embryonic stem cells into extraembryonic lineages by CRISPR-mediated activators.

The recently emerged CRISPR/Cas9 technique has opened a new perspective on readily editing specific genes. When combined with transcription activators, it can precisely manipulate endogenous gene expression. Here, we enhanced the expression of endogenous Cdx2 and Gata6 genes by CRISPR-mediated activators, thus mouse embryonic stem cells (ESCs) were directly converted into two extraembryonic lineages, i.e., typical trophoblast stem cells (TSCs) and extraembryonic endoderm cells (XENCs), which exhibited characters of TSC or XENC derived from the blastocyst extraembryonic lineages such as cell morphology, specific gene expression, and differentiation ability in vitro and in vivo. This study demonstrates that the cell fate can be effectively manipulated by directly activating of specific endogenous gene expression with CRISPR-mediated activator.

Multiple systemic transplantations of human amniotic mesenchymal stem cells exert therapeutic effects in an ALS mouse model.

Amyotrophic lateral sclerosis (ALS) is an adult-onset progressive neurodegenerative disease involving degeneration of motor neurons in the central nervous system. Stem cell treatment is a potential therapy for this fatal disorder. The human amniotic membrane (HAM), an extremely rich and easily accessible tissue, has been proposed as an attractive material in cellular therapy and regenerative medicine because of its advantageous characteristics. In the present study, we evaluate the long-term effects of a cellular treatment by intravenous administration of human amniotic mesenchymal stem cells (hAMSCs) derived from HAM into a hSOD1(G93A) mouse model. The mice received systemic administration of hAMSCs or phosphate-buffered saline (PBS) at the onset, progression and symptomatic stages of the disease. hAMSCs were detected in the spinal cord at the final stage of the disease, in the form of isolates or clusters and were negative for ß-tubulin III and GFAP. Compared with the treatment with PBS, multiple hAMSC transplantations significantly retarded disease progression, extended survival, improved motor function, prevented motor neuron loss and decreased neuroinflammation in mice. These findings demonstrate that hAMSC transplantation is a promising cellular treatment for ALS.