Activated Carbon nanoparticles Loaded with Metformin for Effective Against Hepatocellular Cancer Stem Cells.

Introduction: Hepatocellular cancer stem cells (CSCs) play crucial roles in hepatocellular cancer initiation, development, relapse, and metastasis. Therefore, eradication of this cell population is a primary objective in hepatocellular cancer therapy. We prepared a nanodrug delivery system with activated carbon nanoparticles (ACNP) as carriers and metformin (MET) as drug (ACNP-MET), which was able to selectively eliminate hepatocellular CSCs and thereby increase the effects of MET on hepatocellular cancers. Methods: ACNP were prepared by ball milling and deposition in distilled water. Suspension of ACNP and MET was mixed and the best ratio of ACNP and MET was determined based on the isothermal adsorption formula. Hepatocellular CSCs were identified as CD133+ cells and cultured in serum-free medium. We investigated the effects of ACNP-MET on hepatocellular CSCs, including the inhibitory effects, the targeting efficiency, self-renewal capacity, and the sphere-forming capacity of hepatocellular CSCs. Next, we evaluated the therapeutic efficacy of ACNP-MET by using in vivo relapsed tumor models of hepatocellular CSCs. Results: The ACNP have a similar size, a regular spherical shape and a smooth surface. The optimal ratio for adsorption was MET: ACNP=1:4. ACNP-MET could target and inhibit the proliferation of CD133+ population and decrease mammosphere formation and renewal of CD133+ population in vitro and in vivo. Conclusion: These results not only suggest that nanodrug delivery system increased the effects of MET, but also shed light on the mechanisms of the therapeutic effects of MET and ACNP-MET on hepatocellular cancers. ACNP, as a good nano-carrier, could strengthen the effect of MET by carrying drugs to the micro-environment of hepatocellular CSCs.

Generation of Alzheimer's Disease Transgenic Zebrafish Expressing Human APP Mutation Under Control of Zebrafish appb Promotor.

BACKGROUND: Amyloid peptide precursor (APP) as the precursor protein of peptide betaamyloid (ß-amyloid, Aß), which is thought to play a central role in the pathogenesis of Alzheimer's disease (AD), also has an important effect on the development and progression of AD. Through knocking-in APP gene in animals, numerous transgenic AD models have been set up for the investigation of the mechanisms behind AD pathogenesis and the screening of anti-AD drugs. However, there are some limitations to these models and here is a need for such an AD model that is economic as well as has satisfactory genetic homology with human. METHODS: We generated a new AD transgenic model by knocking a mutant human APP gene (APPsw) in zebrafish with appb promoter of zebrafish to drive the expression of APPsw. RESULTS: Fluorescent image and immunochemistry stain showed and RT-PCR and western blot assay confirmed that APPsw was successfully expressed in the brain, heart, eyes and vasculature of the transgenic zebrafish. Behavioral observation demonstrated that the transgenic zebrafish had AD-like symptoms. Histopathological observation found that there were cerebral ß-amyloidosis and angiopathy (CAA), which induced neuron loss and enlarged pervascular space. CONCLUSION: These results suggest that APPsw transgenic zebrafish well simulate the pathological characters of AD and can be used as an economic AD transgenic model. Furthermore, the new model suggested that APP can express in microvasculatures and cause the Aß generation and deposition in cerebral vessel which further destroys cerebral vascular structure resulting in the development and/or the progress of AD.

The effect of hyaluronic acid functionalized carbon nanotubes loaded with salinomycin on gastric cancer stem cells.

Gastric cancer stem cells (CSCs) play a crucial role in the initiation, development, relapse and metastasis of gastric cancer because they are resistant to a standard chemotherapy and the residual CSCs are able to proliferate indefinitely. Therefore, eradication of this cell population is a primary objective in gastric cancer therapy. Here, we report a gastric CSCs-specifically targeting drug delivery system (SAL-SWNT-CHI-HA complexes) based on chitosan(CHI) coated single wall carbon nanotubes (SWNTs) loaded with salinomycin (SAL) functionalized with hyaluronic acid (HA) can selectively eliminate gastric CSCs. Gastric CSCs were identified as CD44+ cells and cultured in serum-free medium. SAL-SWNT-CHI-HA complexes were capable of inhibiting the self-renewal capacity of CD44+ population, and decrease mammosphere- and colon-formation of CSCs. In addition, the migration and invasion of gastric CSCs were significantly blocked by SAL-SWNT-CHI-HA complexes. Quantitative and qualitative analysis of cellular uptake demonstrated that HA functionalization facilitated the uptake of SWNTs in gastric CSCs while free HA competitively inhibited cellular uptake of SAL-SWNT-CHI-HA delivery system, revealing the mechanism of CD44 receptor-mediated endocytosis. The SAL-SWNT-CHI-HA complexes showed the strongest antitumor efficacy in gastric CSCs by inducing apoptosis, and in CSCs mammospheres by penetrating deeply into the core. Taken altogether, our studies demonstrated that this gastric CSCs-targeted SAL-SWNT-CHI-HA complexes would provide a potential strategy to selectively target and efficiently eradicate gastric CSCs, which is promising to overcome the recurrence and metastasis of gastric cancer and improve gastric cancer treatment.

[The correlated research of acute graft versus host disease after allogeneic stem cell transplantation].

OBJECTIVE: To analyze the relationship between the expression of FasL, Perforin and Granzyme B and the development of acute graft versus host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: The peripheral blood mRNA expression of granzyme B, perforin, fasL from 17 patients after allo-HSCT was detected by competitive quantitative RT-PCR and the relationship between FasL, Granzyme B and Perforin expressions and clinical symptom of aGVHD was analyzed. RESULTS: The expression level of Granzyme B, Perforin and FasL was 4.6 +/- 0.2, 4.5 +/- 0.1, 1.4 +/- 0.1 before aGVHD occurrence respectively, and was 98.7 +/- 2.5, 91.8 +/- 3.4, 61.5 +/- 2.2, after the occurrence in 14 patients (P < or = 0.05). Over expressions of Granzyme B, Perforin, and FasL during acute GVHD were detected in 13 of 14, 12 of 14, and 12 of 14 patients respectively. The upregulated expressions occurred prior to clinical symptom of aGVHD. CONCLUSION: The expressions of Granzyme B, Perforin, and FasL were significantly high in patients with acute aGVHD. Monitoring of the expressions, might predict the occurrence of clinical aGVHD and it severity and prognosis.

[Intraperitoneal chemotherapy with mitomycin C bound to activated carbon nanoparticles for nude mice bearing human gastric carcinoma].

OBJECTIVE: To prepare a new dosage formulation of activated carbon nanoparticles adsorbing mitomycin C (MMC-ACNP) and evaluate the beneficial effects of intraperitoneally applied MMC-ACNP as a drug delivery system for lymphatic targeting in preventing metastasis and recurrence of gastric cancer. METHODS: MMC-ACNP was prepared. Acute toxicity after its intraperitoneal administration was evaluated. An experiment on nude mice model with transplanted human gastric cancer in 6 groups was completed to assess the effects of drugs on intra-abdominal carcinomatosis. RESULTS: The LD50 of MMC-ACNP was 46.80 mg/kg (in terms of MMC) while that of MMC aqueous solution was 9.33 mg/kg. The toxicity of MMC-ACNP was much less than that of the solution form. MMC-ACNP was superior to MMC aqueous solution in controlling carcinomatosis and tumor growth by intraperitoneal administration. Despite the high dose of MMC, leukopenia and thrombocytopenia were not observed in the MMC-ACNP treated group. Fine activated carbon particles adsorbing MMC entered the nuclei of tumor cells, so that the effects of the anticancer drug were reinforced. CONCLUSION: MMC-ACNP gives a good promise of clinical use due to its advantages such as high selectivity and low toxicity.

Ultrastructrural observation of the membrane surface of kainic acid-treated hippocampal neurons by atomic force microscopy.

OBJECTIVE: To observe the three-dimensional morphological changes on the membrane surface of primary cultured rat hippocampal neurons in response to kainic acid (KA) exposure. METHODS: After isolation and primary culture, Wistar rat hippocampal neurons were treated with KA at the concentrations of 0, 25, and 250 micromol/L for different durations (10 and 100 min) to observe the subsequent changes in the membrane surface structure of the neurons by nano-scale scanning with an atomic force microscope (AFM). RESULTS: Normal neurons displayed smooth membrane surface with even and regular undulation, while the neurons treated with KA, in contrast, presented degenerative changes characterized by cell swelling and coarse membrane surface with processes and holes. As the treatment was prolonged and KA concentration increased, the changes became more evident. CONCLUSION: As a result of the toxic effect of KA, the membrane surface ultrastructure of rat hippocampal neurons undergo obvious changes, which can be clearly observed and quantitatively analyzed by means of AFM.