Functional comparison of the human epidermal growth factor receptor and telomerase reverse transcriptase promoters in canine tumor cells.

We previously showed that the promoter region of the human epidermal growth factor receptor (hEGFR) gene elicits high transduction efficiency, with transgene expression restricted to canine breast tumor cells. However, it was unclear whether this promoter induces tumor cell-specific transgene expression in canine urothelial carcinoma cells. Furthermore, compared with studies in human cancer cells, the utility of the telomerase reverse transcriptase (TERT) gene promoter for therapeutic transgene expression in canine cancer cells has not been evaluated thus far. Here, we compared the activity of these promoters in canine mammary tumor and urothelial carcinoma cells. Our results showed that compared with the TERT promoter, the hEGFR promoter was more useful as a tumor-specific promoter to induce efficient transgene expression in canine tumor cells.

Effect of Bacillus subtilis C-3102 on bone mineral density in healthy postmenopausal Japanese women: a randomized, placebo-controlled, double-blind clinical trial.

Gut microbiota influence the host immune system and are associated with various diseases. In recent years, postmenopausal bone loss has been suggested to be related to gut microbiota. In the present study, we investigated the treatment effect of the probiotic Bacillus subtilis C-3102 (C-3102) on bone mineral density (BMD) and its influence on gut microbiota in healthy postmenopausal Japanese women. Seventy-six healthy postmenopausal Japanese women were treated with a placebo or C-3102 spore-containing tablets for 24 weeks. When compared with the placebo, C-3102 significantly increased total hip BMD (placebo = 0.83 ± 0.63%, C-3102 = 2.53 ± 0.52%, p=0.043). There was a significant group-by-time interaction effect for urinary type I collagen cross-linked N-telopeptide (uNTx) (p=0.033), a marker of bone resorption. Specifically, the C-3102 group showed significantly lower uNTx when compared with the placebo group at 12 weeks of treatment (p=0.015). In addition, in the C-3102 group, there was a trend towards a decrease in the bone resorption marker tartrate-resistant acid phosphatase isoform 5b (TRACP-5b) when compared with the placebo group at 12 weeks of treatment (p=0.052). The relative abundance of genus Bifidobacterium significantly increased at 12 weeks of treatment compared with the baseline in the C-3102 group. The relative abundance of genus Fusobacterium was significantly decreased in the C-3102 group at 12 and 24 weeks of treatment compared with the baseline. These data suggested that C-3102 improves BMD by inhibiting bone resorption and modulating gut microbiota in healthy postmenopausal women.

Expression of HIF-1α ODD domain fused canine caspase 3 by EGFR promoter-driven adenovirus vector induces cytotoxicity in canine breast tumor cells under hypoxia.

Adenovirus (Ad) vectors are widely used in cancer gene therapies. However, compared to human patients, relatively limited information is available on gene transduction efficiency or cell-specific cytotoxicity in canine tumor cells transduced with Ad vectors. Since epidermal growth factor receptor (EGFR) is highly expressed on canine breast tumor cells, we sought to develop an Ad vector based on the RGD fiber-mutant adenovirus vector (AdRGD) that expresses canine caspase 3 under the control of EGFR promoter. The aims of this study were to achieve high transduction efficiency with transgene expression restricted to canine breast tumor cells. Using EGFR promoter-driven AdRGD, we were able to restrict transgene expression to canine breast tumor cells with no evidence of expression in normal cells. Canine breast tumor cells transduced with EGFR promoter-driven AdRGD carrying canine caspase 3 gene showed cytotoxic activity. We constructed a second AdRGD vector that expressed oxygen-dependent degradation (ODD)-caspase 3 under the control of the EGFR promoter; the fusion protein contains a core part of the ODD domain of hypoxia inducible factor-1 alpha (HIF-1α) fused to caspase 3. Transduction of canine breast tumor cells with EGFR promoter-driven AdRGD expressing ODD-caspase 3 induced a higher rate of cell death under hypoxic conditions compared with under normoxia. The results indicate that the EGFR promoter-driven AdRGD vectors will be of value for tumor-specific transgene expression and safe cancer gene therapy in dogs.

Cytoplasm-responsive nanocarriers conjugated with a functional cell-penetrating peptide for systemic siRNA delivery.

To develop a gene carrier for cancer therapy by systemic injection, we synthesized methoxypolyethylene glycol-polycaprolactone (MPEG-PCL) diblock copolymers conjugated with a cytoplasm-responsive cell-penetrating peptide (CPP), CH2R4H2C (C, Cys; H, His; R, Arg). The carrier/small interfering RNA (siRNA) complexes (N/P ratio of 20) had a particle size of approximately 50 nm and stabilized the siRNA against RNase. The cellular uptake ability of the carrier/FAM-siRNA complexes with fetal bovine serum was significantly higher than that of naked FAM-siRNA. In addition, the carrier/anti-vascular endothelial growth factor siRNA (siVEGF) complexes attained a significantly greater silencing effect than naked siVEGF with low cytotoxicity, resulting from higher uptake, early endosomal escape, and efficient release from the complexes in the cytoplasm. Furthermore, intravenous injection of MPEG-PCL-CH2R4H2C/siVEGF complexes had a significantly higher anti-tumor effect in S-180 tumor-bearing mice, which could be attributed to the rigid compaction of siRNA by ionic interactions and disulfide linkages in the CPP polymer micelles in the blood, as well as higher release following cleavage of the disulfide bonds in the reductive cytosol. Taken together, our data demonstrated that these cytoplasm-responsive polymer micelles conjugated with multi-functional CPP, could facilitate siVEGF delivery to tumor tissues after systemic injection and could exert an extremely strong anti-tumor effect.

Suppression of tumor growth by systemic delivery of anti-VEGF siRNA with cell-penetrating peptide-modified MPEG-PCL nanomicelles.

Small interfering RNAs (siRNAs) have potential applications for many diseases, such as cancer, since siRNAs can specifically silence disease-associated genes. However, effective siRNA carriers need to be developed to overcome the low siRNA stability in vivo, to form stable complexes and to facilitate intracellular uptake. In this study, to develop a carrier for systemic siRNA delivery, we prepared methoxy poly(ethylene glycol) (MPEG)/polycaprolactone (PCL) diblock copolymers conjugated with a cell-penetrating peptide, Tat, via a disulfide linkage, and evaluated their ability as an siRNA carrier. The particle size of MPEG-PCL-SS-Tat/siRNA complexes was approximately 100-200 nm. The cellular uptake ability after transfection with FAM-siRNA with MPEG-PCL-SS-Tat was significantly higher than that with FAM-siRNA only. MPEG-PCL-SS-Tat did not induce substantial cytotoxicity. Intravenous injection of MPEG-PCL-SS-Tat/anti-vascular endothelial growth factor (VEGF) siRNA (siVEGF) complexes achieved a high anti-tumor effect in tumor-bearing mice. These results suggest that MPEG-PCL-SS-Tat is a potentially effective siRNA carrier for silencing genes in vitro and in vivo.

A cytoplasm-sensitive peptide vector cross-linked with dynein light chain association sequence (DLCAS) enhances gene expression.

We previously engineered a novel, non-viral, multifunctional gene vector (STR-CH(2)R(4)H(2)C) containing stearoyl (STR) and a block peptide consisting of Cys (C), His (H), and Arg (R). STR-CH(2)R(4)H(2)C forms a nano-complex with pDNA and is stabilized by electronic interactions and disulfide cross linkages. In blood, pDNA, a cytosol-sensitive gene vector, is released from the complex into the cytosol. The current study aimed to make STR-CH(2)R(4)H(2)C capable of active nuclear localization. The dynein light chain association sequence (DLCAS) was disulfide cross-linked to STR-CH(2)R(4)H(2)C/pDNA through disulfide linkages, and the gene expression ability of this DLCAS cross-linked gene vector was evaluated. We examined the gene transfection efficiency of S-180 cells transfected with the STR-CH(2)R(4)H(2)C/DLCAS/pDNA complex. STR-CH(2)R(4)H(2)C/DLCAS/pDNA showed significantly higher and faster gene expression compared with STR-CH(2)R(4)H(2)C/pDNA. We also evaluated the cellular uptake ability of STR-CH(2)R(4)H(2)C/DLCAS/Cy5-labeled pDNA complex. STR-CH(2)R(4)H(2)C/DLCAS/pDNA showed significantly lower cellular uptake compared with STR-CH(2)R(4)H(2)C/pDNA. This result indicates that high gene expression of STR-CH(2)R(4)H(2)C/DLCAS/pDNA does not facilitate its cellular uptake. In addition, the gene expression of DLCAS/STR-CH(2)R(4)H(2)C/pDNA in S-180 cells pretreated with the tubulin polymerization inhibitor, nocodazole (NCZ), was significantly lower than that in the absence of NCZ. These results indicate that the high transfection efficiency of DLCAS/STR-CH(2)R(4)H(2)C/pDNA is dependent on intra-cellular transport utilizing the microtubule motor protein, dynein. Taken together, our results suggest that DLCAS-modified STR-CH(2)R(4)H(2)C may be a promising gene delivery system.

Cell-penetrating peptide-modified block copolymer micelles promote direct brain delivery via intranasal administration.

PURPOSE: In order to develop non-invasive and effective nose-to-brain delivery of drugs, we synthesized Tat analog-modified methoxy poly(ethylene glycol) (MPEG)/poly(ε-caprolactone) (PCL) amphiphilic block copolymers through the ester bond. METHODS: We evaluated the brain distribution of coumarin, acting as a model chemical, after intravenous or intranasal administration of MPEG-PCL. In addition, cellular uptake of coumarin by rat glioma cells transfected with coumarin-loaded MPEG-PCL or MPEG-PCL-Tat was determined. Finally, we determined the brain distribution and biodistribution after intranasal administration of coumarin-loaded MPEG-PCL-Tat. RESULTS: The amount of coumarin in the brain after intranasal administration was significantly higher than that after intravenous administration. In addition, cellular uptake of coumarin using MPEG-PCL was the lowest, while cellular uptake of coumarin using Tat-modified MPEG-PCL (MPEG-PCL-Tat) was higher than that of MPEG-PCL. Therefore, the brain distribution of coumarin administered using MPEG-PCL-Tat was significantly greater than that using MPEG-PCL. Then, the coumarin distribution after MPEG-PCL-Tat administration in non-targeted tissues (lung, liver, heart, kidney and spleen) was lower than that after coumarin administration without nanomicelles. CONCLUSION: We have demonstrated that utilization of nano-sized micelles modified with Tat can facilitate direct intranasal brain delivery.

A novel, bio-reducible gene vector containing arginine and histidine enhances gene transfection and expression of plasmid DNA.

We have engineered a novel, non-viral, multifunctional gene vector (STR-CH(2)R(4)H(2)C) that contained stearoyl (STR) and a block peptide consisting of Cys (C), His (H), and Arg (R). STR-CH(2)R(4)H(2)C can form a stable nano-complex with plasmid DNA (pDNA) based on electronic interactions and disulfide cross linkages. In this study, we evaluated the efficacy of STR-CH(2)R(4)H(2)C as a gene vector. We first determined the optimal weight ratio for STR-CH(2)R(4)H(2)C/pDNA complexes. The complexes with a weight ratio of 50 showed the highest transfection efficacy. We also examined the transfection efficacy of STR-CH(2)R(4)H(2)C/pDNA complexes with or without serum and compared STR-CH(2)R(4)H(2)C/pDNA transfection efficacy with that of Lipofectamine. Even in the presence of serum, STR-CH(2)R(4)H(2)C showed higher transfection efficacy than did Lipofectamine. In addition, we determined the mechanism of transfection of the STR-CH(2)R(4)H(2)C/pDNA complexes using various cellular uptake inhibitors and evaluated its endosomal escape ability using chloroquine. Macropinocytosis was main cellular uptake pathway of STR-CH(2)R(4)H(2)C/pDNA complexes. Our results suggested that STR-CH(2)R(4)H(2)C is a promising gene delivery system.

Disulfide crosslinked stearoyl carrier peptides containing arginine and histidine enhance siRNA uptake and gene silencing.

The siRNA has been expected to apply for several diseases such as cancer since siRNA specifically silences the disease-associated genes. However, effective gene carriers should be developed to overcome the low siRNA stability in vivo, form stable complexes and facilitate intracellular uptake of siRNA. In this study, to develop a safe and efficient siRNA carrier, stearoyl (STR) peptides with Cys (C), Arg (R), and His (H) residues that can form disulfide cross linkages via Cys (C) were synthesized, and their suitability as siRNA carriers was evaluated. The particle size of STR-CH(2)R(4)H(2)C/siRNA complexes was about 100 nm. The cellular uptake ability after transfection with FAM-siRNA with STR-CH(2)R(4)H(2)C, CH(2)R(4)H(2)C, or STR-GH(2)R(4)H(2)G was significantly higher than that with FAM-siRNA only. STR-CH(2)R(4)H(2)C showed the highest cellular uptake ability when compared with CH(2)R(4)H(2)C and STR-GH(2)R(4)H(2)G. STR-CH(2)R(4)H(2)C did not induce substantial cytotoxicity. The intratumor injection of STR-CH(2)R(4)H(2)C/vascular endothelial growth factor (VEGF) siRNA (siVEGF) complexes achieved a high anti-tumor effect in tumor bearing mice. These results suggest STR-CH(2)R(4)H(2)C has potential of effective siRNA carrier possible to exercise silencing effect in vitro and in vivo.

Development of cell-penetrating peptide-modified MPEG-PCL diblock copolymeric nanoparticles for systemic gene delivery.

To develop a safe and efficient systemic non-viral gene vector, methoxy poly(ethylene glycol) (MPEG)/poly(epsilon-caprolactone) (PCL) diblock copolymers conjugated with a Tat analog through the ester or disulfide linkage were synthesized and their suitability as a systemic non-viral gene carrier evaluated. The physicochemical properties of the MPEG-PCL diblock copolymers were determined by GPC, (1)H NMR and FT-IR spectroscopy. The particle sizes and in vitro (COS7 and S-180 cells) transfection efficiencies and cytotoxicity were evaluated. Furthermore, the luciferase activity was then determined in various tissues after intravenous injection of MPEG-PCL-SS-Tat/pCMV-Luc complex into mice bearing S-180 cells. The particle sizes of the MPEG-PCL-Tat copolymers with or without pDNA were about 40 and 60nm, respectively. The luciferase activity in COS7 cells transfected with pCMV-Luc with MPEG-PCL-ester-Tat or MPEG-PCL-SS-Tat was higher than that with pDNA only. MPEG-PCL-SS-Tat greatly increased the transfection efficiency compared to MPEG-PCL-ester-Tat in COS7 and S-180 cells. In an in vitro cytotoxicity test MPEG-PCL-SS-Tat did not induce any remarkable cytotoxicity. In an in vivo experiment, the synthesized MPEG-PCL-SS-Tat copolymers promoted the delivery and expression of pDNA into tumor tissue in tumor-bearing mice. In conclusion, this vector might be applicable as a tumor-targeting non-viral systemic gene carrier in the clinical setting.

Pulmonary myoepithelial carcinoma resembling matrix-producing carcinoma of the breast: case report and review of the literature.

We report a case of pulmonary myoepithelial carcinoma with extensive myxohyaline stroma, resembling matrix-producing carcinoma of the breast. A 76-year-old Japanese man presented with a nodular lesion in the left lung (S8), and underwent partial resection of the left lower lobe. Microscopically, the resected tumor was relatively well circumscribed with central hypocellular myxohyaline and peripheral hypercellular area. In the central area, eosinophilic and clear polygonal cells proliferated in a cord-like or reticulated pattern with extensive myxohyaline stroma, while the peripheral area was composed of solid lobules of different shapes and sizes with occasional comedonecrosis. The tumor cells were markedly atypical with frequent mitotic figures. Vascular and lymphatic invasion was evident with regional lymph node metastasis. No squamous or glandular differentiation was evident in the tumor. Immunohistochemical staining implied myoepithelial differentiation. The patient developed multiple brain metastases, and died of the disease 11 months after the surgery. In this report, we discuss the histopathologic uniqueness of the present case together with a review of the literature.

A case report of off-pump coronary artery bypass grafting associated with recent neurological deficit.

A 77-year-old man with a history of cerebral infarction was admitted to our hospital with chest oppression. Coronary angiography revealed 2-vessel disease involving left main trunk. Coronary artery bypass grafting to left anterior descending artery and obtuse marginal branch was scheduled, but the patient developed hemiparesis and the scheduled coronary artery bypass grafting was postponed by at least one month. Unfortunately, the patient complained of severe chest pain at midnight of the second day from the onset of the neurological deficits and went into cardiogenic shock. We performed off-pump coronary artery bypass grafting to left anterior descending artery on the 5th day from the onset of the neurological deficits. His postoperative course was uneventful. Off-pump coronary artery bypass grafting is appropriate as an alternative procedure for high-risk patients with recent neurological deficits.