Development of a growth-hormone-conjugated nanodiamond complex for cancer therapy.

It is highly desirable to develop a therapeutic, observable nanoparticle complex for specific targeting in cancer therapy. Growth hormone (GH) and its antagonists have been explored as cancer cell-targeting molecules for both imaging and therapeutic applications. In this study, a low toxicity, biocompatible, therapeutic, and observable GH-nanoparticle complex for specifically targeting growth hormone receptor (GHR) in cancer cells was synthesized by conjugating GH with green fluorescence protein and carboxylated nanodiamond. Moreover, we have shown that this complex can be triggered by laser irradiation to create a "nanoblast" and induce cell death in the A549 non-small-cell lung cancer cell line via the apoptotic pathway. This laser-mediated, cancer-targeting platform can be widely used in cancer therapy.

Synthesis of apolipoprotein B lipoparticles to deliver hydrophobic/amphiphilic materials.

To develop a drug delivery system (DDS), it is critical to address challenging tasks such as the delivery of hydrophobic and amphiphilic compounds, cell uptake, and the metabolic fate of the drug delivery carrier. Low-density lipoprotein (LDL) has been acknowledged as the human serum transporter of natively abundant lipoparticles such as cholesterol, triacylglycerides, and lipids. Apolipoprotein B (apo B) is the only protein contained in LDL, and possesses a binding moiety for the LDL receptor that can be internalized and degraded naturally by the cell. Therefore, synthetic/reconstituting apoB lipoparticle (rABL) could be an excellent delivery carrier for hydrophobic or amphiphilic materials. Here, we synthesized rABL in vitro, using full-length apoB through a five-step solvent exchange method, and addressed its potential as a DDS. Our rABL exhibited good biocompatibility when evaluated with cytotoxicity and cell metabolic response assays, and was stable during storage in phosphate-buffered saline at 4 °C for several months. Furthermore, hydrophobic superparamagnetic iron oxide nanoparticles (SPIONPs) and the anticancer drug M4N (tetra-O-methyl nordihydroguaiaretic acid), used as an imaging enhancer and lipophilic drug model, respectively, were incorporated into the rABL, leading to the formation of SPIONPs- and M4N- containing rABL (SPIO@rABL and M4N@rABL, respectively). Fourier transform infrared spectroscopy suggested that rABL has a similar composition to that of LDL, and successfully incorporated SPIONPs or M4N. SPIO@rABL presented significant hepatic contrast enhancement in T2-weighted magnetic resonance imaging in BALB/c mice, suggesting its potential application as a medical imaging contrast agent. M4N@rABL could reduce the viability of the cancer cell line A549. Interestingly, we developed solution-phase high-resolution transmission electron microscopy to observe both LDL and SPIO@rABL in the liquid state. In summary, our LDL-based DDS, rABL, has significant potential as a novel DDS for hydrophobic and amphiphilic materials, with good cell internalization properties and metabolicity.

Anthracenedione-methionine conjugates are novel topoisomerase II-targeting anticancer agents with favorable drug resistance profiles.

Structure-associated drug resistance and DNA-unwinding abilities have greatly limited the clinical usage of anthracenediones, including mitoxantrone (MX) and ametantrone (AT), which intercalate into DNA and induce topoisomerase II (TOP2)-mediated DNA break. We studied a series of 1,4-bis(2-amino-ethylamino) MX- and AT-amino acid conjugates (M/AACs) and showed that abilities in cancer cell killing correlate with the amounts of chromosomal DNA breaks induced by M/AACs. Notably, the 1,4-bis-L/l-methionine-conjugated MAC (L/LMet-MAC) exhibits DNA-breaking, cancer cell-killing and anti-tumor activities rivaling those of MX. Interestingly, l- and d-form Met-M/AACs unwind DNA poorly compared to MX and AT. The roles of the two human TOP2 isozymes (hTOP2α and 2ß) in the L/LMet-MAC-induced DNA breakage and cancer cell-killing were suggested by the following observations: (i) M/AAC-induced DNA breakage, cytotoxicity and apoptosis are greatly reduced in various TOP2-deficient conditions; (ii) DNA breaks induced by MACs are highly reversible and effectively antagonized by the TOP2 catalytic inhibitors; (iii) MACs induced differential TOP2-mediated DNA cleavage in vitro using recombinant hTOP2α proteins and the formation of hTOP2α/ßcc in the cell culture system. Interestingly, d-aa-conjugated MACs often caused a lower level in hTOP2-mediated DNA breaks and cell-killing than the corresponding l-form ones indicating a steric-specific effect of MACs. Together, our results suggest that both enzyme- and DNA-drug interactions might contribute to TOP2-targeting by M/AACs. Furthermore, Met-MACs are poor substrates for the MDR1 transporter. Therefore, L/LMet-MAC represents a promising class of TOP2-targeting drugs with favorable drug resistance profiles.

Induced interleukin-19 contributes to cell-mediated immunosuppression in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.

BACKGROUND: Coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) promotes immunosuppression, which predisposes patients to infectious complications. We investigated the role of interleukin (IL)-19 in the functions of CD4+ T cells in patients undergoing CABG with CPB. METHODS: Blood samples were withdrawn from 42 patients undergoing elective CABG with CPB. Serum levels of IL-19 were analyzed by enzyme-linked immunosorbent assay (ELISA). The CD4+/CD25+ T-cell population was determined with flow cytometry. Isolated CD4+ T cells were cultured and assayed for proliferation and cytokine production under phorbol myristate acetate/ionomycin stimulation. Cytokine production and Foxp3 mRNA expression in CD4+ T cells from healthy volunteers with or without IL-19 treatment were determined with ELISA and real-time polymerase chain reaction, respectively. RESULTS: Proliferation percentages were 162%, 48%, 34%, and 39%, and interferon (IFN)-γ production was 1.22 ng/mL, 0.56 ng/mL, 0.33 ng/mL, and 0.35 ng/mL in the CD4+ T cells of patients before CPB and at 24 hours, 48 hours, and 96 hours, respectively, after CPB. Serum levels of IL-19 were higher but negatively correlated with CD4+ T-cell proliferation and IFN-γ production. The populations of CD4+/CD25+ T cells and expression of Foxp3 mRNA in T cells were higher and were positively correlated with IL-19 levels after CPB. Treatment with IL-19 reduced T-cell proliferation and IFN-γ production, increased Foxp3 mRNA expression, and induced the regulatory activity of CD4+ T cells. CONCLUSIONS: Interleukin-19 reduces T-cell responses and promotes the regulatory activity of CD4+ T cells. Induced IL-19 in patients undergoing CABG with CPB contributes to cell-mediated immunosuppression.

Propofol increases bone morphogenetic protein-7 and decreases oxidative stress in sepsis-induced acute kidney injury.

BACKGROUND: Pro-inflammatory cytokines and free radicals damage renal tissue leading to acute kidney injury (AKI) during sepsis. Bone morphogenetic protein-7 (BMP-7) represses tumour necrosis factor (TNF)-α-induced inflammatory responses and protects kidney from injury. The sedative agent, propofol, has immunomodulatory and antioxidative properties. The present study investigated whether propofol could reduce AKI in caecal ligation and puncture (CLP) mice and the possible mechanism behind this. METHODS: Mice were treated with propofol or saline immediately and 12 h after CLP surgery. Kidney injury, survival and cytokine expressions of CLP mice were observed 24 h after CLP surgery. In vitro, lipopolysaccharide (LPS)-stimulated rat mesangial cells (RMCs) or hydrogen peroxide (H(2)O(2))-exposed murine kidney epithelial cells (M1) were treated with propofol. The expression of BMP-7, TNF-α and monocyte chemotactic protein (MCP)-1 in CLP mice kidney, RMCs or M1 cells was determined by RT-PCR. Free radical generation and cell death of RMCs and M1 cells were analysed. Nuclear factor (NF)-κB and peroxisome proliferator-activated receptor (PPAR)-γ expressions in LPS-stimulated RMCs were determined by western blotting. RESULTS: Propofol increased survival and ameliorated AKI in CLP mice. Propofol increased BMP-7 expression but decreased TNF-α and MCP-1 expressions in the kidney of CLP mice and LPS-stimulated RMCs. Propofol also inhibited free radical generation and cell death in LPS-stimulated RMCs and decreased the TNF-α expression and cell death in H(2)O(2)-exposed M1 cells. Moreover, propofol decreased NF-κB but increased PPAR-γ expression in LPS-stimulated RMCs. CONCLUSIONS: Propofol treatment could protect kidney from sepsis-induced AKI by increasing BMP-7 expression, decreasing inflammatory cytokines and inhibiting oxidative stress.

Splenic infarction and abscess complicating infective endocarditis.

Acute abdominal pain is one of the most common conditions confronted in the emergency department. Clues related to splenic infarction may be obscured, and the diagnosis is quite challenging even for experienced physicians or surgeons. For every patient diagnosed with splenic infarction, a scrutiny on the possible source of emboli should be carried out. In addition, splenic abscess must be suspected in patients of splenic infarction, especially if the infectious signs persist despite appropriate treatment. Rapid diagnosis and treatment are essential as its course can prove fatal. Infective endocarditis is the most common condition predisposing a patient to splenic abscess. Indeed, splenic abscess or infarction may be a disease entity at different stages in patients of infective endocarditis due to septic emboli of the spleen. The treatment of choice has been antibiotics, splenectomy, and valve replacement surgery. Herein, we report a case of splenic abscess and infective endocarditis cured by antibiotic treatment without the aid of drainage or surgery.

D:C-friedooleanane-type triterpenoids from Lagenaria siceraria and their cytotoxic activity.

Four new D:C-friedooleanane-type triterpenes, 3 beta-O-(E)-feruloyl-D:C-friedooleana-7,9(11)-dien-29-ol (1), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-ol (2), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-oic acid (3), and methyl 2 beta,3 beta-dihydroxy-D:C-friedoolean-8-en-29-oate (6), together with five known triterpenes with the same skeleton, 3-epikarounidiol (4), 3-oxo-D:C-friedoolena-7,9(11)-dien-29-oic acid (5), bryonolol (7), bryononic acid (8), and 20-epibryonolic acid (9), were isolated from the methanol extract of the stems of Lagenaria siceraria. The structures of those compounds were elucidated using spectroscopic methods. Compounds 3 and 9 showed significant cytotoxic activity against the SK-Hep 1 cell line with IC50 values of 4.8 and 2.1 microg/ml, respectively. Based on these initially promising results, the two D:C-friedooleanane triterpenes merit further study as potential anticancer agents.

Synthesis, DNA binding, and cytotoxicity of 1,4-bis(2-amino-ethylamino)anthraquinone-amino acid conjugates.

Two series of 1,4-bis(2-amino-ethylamino)anthraquinone-amino acid conjugates (BACs), ametantrone (AT)-amino acid conjugates (AACs) and mitoxantrone (MX)-amino acid conjugates (MACs), were designed and synthesized. The DNA binding of BACs was evaluated by DNA thermal denaturation experiment. In the series, the methionine-substituted BACs had the weakest DNA binding, while the lysine-substituted BACs had the highest T(m) values. The abilities of BACs to inhibit the growth of MCF-7, NCI-H460, SF-268, and PC-3 cell lines were determined. l-Met-MAC 16 and l-Lys-MAC 20 were the most potent growth inhibitors. MAC 16 was more cytotoxic than MX, whereas the T(m) of MAC 16 was much lower than that of MX. In contrast to MAC 16, l-Lys-MAC 20 demonstrated higher T(m) than MX. These data suggested that Met-BACs possessed a different pharmacological profile, in which the ability to stabilize DNA is not parallel to the ability to kill cancer cells, from that of AT and MX. The primary mechanism of cytotoxicity for MAC 16 was most likely through TOP2 poisoning. Therefore, MAC 16 may provide a lead for the development of novel generations of anthraquinone-type antitumor agents.