Apatinib and gamabufotalin co-loaded lipid/Prussian blue nanoparticles for synergistic therapy to gastric cancer with metastasis.

Due to the non-targeted release and low solubility of anti-gastric cancer agent, apatinib (Apa), a first-line drug with long-term usage in a high dosage often induces multi-drug resistance and causes serious side effects. In order to avoid these drawbacks, lipid-film-coated Prussian blue nanoparticles (PB NPs) with hyaluronan (HA) modification was used for Apa loading to improve its solubility and targeting ability. Furthermore, anti-tumor compound of gamabufotalin (CS-6) was selected as a partner of Apa with reducing dosage for combinational gastric therapy. Thus, HA-Apa-Lip@PB-CS-6 NPs were constructed to synchronously transport the two drugs into tumor tissue. In vitro assay indicated that HA-Apa-Lip@PB-CS-6 NPs can synergistically inhibit proliferation and invasion/metastasis of BGC-823 cells via downregulating vascular endothelial growth factor receptor (VEGFR) and matrix metalloproteinase-9 (MMP-9). In vivo assay demonstrated strongest anti-tumor growth and liver metastasis of HA-Apa-Lip@PB-CS-6 NPs administration in BGC-823 cells-bearing mice compared with other groups due to the excellent penetration in tumor tissues and outstanding synergistic effects. In summary, we have successfully developed a new nanocomplexes for synchronous Apa/CS-6 delivery and synergistic gastric cancer (GC) therapy.

Bio-nanocomplexes with autonomous O2 generation efficiently inhibit triple negative breast cancer through enhanced chemo-PDT.

As one kind of aggressive cancer, triple-negative breast cancer (TNBC) has become one of the major causes of women mortality worldwide. Recently, combinational chemo-PDT therapy based on nanomaterials has been adopted for the treatment of malignant tumor. However, the efficacy of PDT was partly compromised under tumor hypoxia environment due to the lack of sustainable O2 supply. In this study, CeO2-loaded nanoparticles (CeNPs) with peroxidase activity were synthesized to autonomously generate O2 by decomposing H2O2 within tumor region and reprogramming the hypoxia microenvironment as well. Meanwhile, the compound cinobufagin (CS-1) was loaded for inhibiting TNBC growth and metastasis. Moreover, the hybrid membrane camouflage was adopted to improve the biocompatibility and targeting ability of nanocomplexes. In vitro assay demonstrated that decomposition of H2O2 by CeO2 achieved sustainable O2 supply, which accordingly improved the efficacy of PDT. In turn, the generated O2 improved the cytotoxicity and anti-tumor migration effect of CS-1 by downregulating HIF-1α and MMP-9 levels. In vivo assay demonstrated that the combination of CS-1 and PDT significantly inhibited the growth and distance metastasis of tumor in MDA-MB-231 bearing mice. Thus, this chemo-PDT strategy achieved satisfactory therapeutic effects by smartly utilizing the enzyme activity of nanodrugs and special micro-environment of tumor.

Research on Classification of COVID-19 Chest X-Ray Image Modal Feature Fusion Based on Deep Learning.

Most detection methods of coronavirus disease 2019 (COVID-19) use classic image classification models, which have problems of low recognition accuracy and inaccurate capture of modal features when detecting chest X-rays of COVID-19. This study proposes a COVID-19 detection method based on image modal feature fusion. This method first performs small-sample enhancement processing on chest X-rays, such as rotation, translation, and random transformation. Five classic pretraining models are used when extracting modal features. A global average pooling layer reduces training parameters and prevents overfitting. The model is trained and fine-tuned, the machine learning evaluation standard is used to evaluate the model, and the receiver operating characteristic (ROC) curve is drawn. Experiments show that compared with the classic model, the classification method in this study can more effectively detect COVID-19 image modal information, and it achieves the expected effect of accurately detecting cases.

A novel Apigenin derivative suppresses renal cell carcinoma via directly inhibiting wild-type and mutant MET.

MET, the receptor of hepatocyte growth factor (HGF), is a driving factor in renal cell carcinoma (RCC) and also a proven drug target for cancer treatment. To improve the activity and to investigate the mechanisms of action of Apigenin (APG), novel derivatives of APG with improved properties were synthesized and their activities against Caki-1 human renal cancer cell line were evaluated. It was found that compound 15e exhibited excellent potency against the growth of multiple RCC cell lines including Caki-1, Caki-2 and ACHN and is superior to APG and Crizotinib. Subsequent investigations demonstrated that compound 15e can inhibit Caki-1 cell proliferation, migration and invasion. Mechanistically, 15e directly targeted the MET kinase domain, decreased its auto-phosphorylation at Y1234/Y1235 and inhibited its kinase activity and downstream signaling. Importantly, 15e had inhibitory activity against mutant MET V1238I and Y1248H which were resistant to approved MET inhibitors Cabozantinib, Crizotinib or Capmatinib. In vivo tumor graft study confirmed that 15e repressed RCC growth through inhibition of MET activation. These results indicate that compound 15e has the potential to be developed as a treatment for RCC, and especially against drug-resistant MET mutations.

A hybrid membrane coating nanodrug system against gastric cancer via the VEGFR2/STAT3 signaling pathway.

Although drug combination has proved to be an efficient strategy for clinic gastric cancer therapy, how to further improve their bioavailability and reduce the side effects are still challenges due to the low solubility and untargeted ability of drugs. Recently, newly emerging nanotechnology has provided an alternative for constructing new drug delivery systems with high targeting ability and solubility. In this study, a pH-responsive liposome (Liposome-PEO, LP) loaded with apatinib (AP) and cinobufagin (CS-1) was used for combinational therapy against gastric cancer after coating with a hybrid membrane (R/C). The results indicated that the constructed nanocomplex LP-R/C@AC not only efficiently killed tumor cells in vitro by inducing apoptosis, autophagy, and pyroptosis, but also significantly inhibited tumor invasion and metastasis via the VEGFR2/STAT3 pathway. Moreover, it showed stronger anti-tumor activity in gastric cancer-bearing mouse models, as compared to the sole drugs. A naturally-derived hybrid cell membrane coating bestowed nanocomplexes with enhanced biointerfacing including prolonged circulation time and targeting ability.

The Effect of Light Source Line Width on the Spectrum Resolution of Dual-Frequency Coherent Detection Signals.

In this paper, the power spectrum resolution problem of dual-frequency coherent mixing signals is analyzed when the Doppler frequency difference is small. The power spectrum function formula of the four optical coherent mixing signals is obtained using statistical theory and the Wiener-Khinchin theorem. The influence of delay time and light source line width on the power spectrum of dual-frequency coherent signals is analyzed using this formula. The results show that delay time only affects the peak of the power spectrum of the coherent signal. An increase in the line width of the light source broadens the signal power spectrum and reduces the peak value. The necessary condition for distinguishing the Doppler frequency difference is that the theoretical Doppler frequency difference is greater than 1/5 times the line width of the light source.

[Molecular Imaging in vivo Detection of EGFR Mutations in Non-small Cell Lung Cancer].

An ever increasing number of drugs directed as epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) bring a new revolution for non-small cell lung cancer (NSCLC) therapy, and many large scales of studies show that only people with EGFR-sensitive mutation can benefit from these drugs. The main method of EGFR mutation detection is to analyze the DNA sequence of EGFR, which can be the lung cancer tissue, pleural fluid tumor cells, circulating tumor cells and peripheral blood free DNA obtained by surgery or puncture, the biggest drawback is that the heterogeneity of EGFR mutation cannot be analyzed. However, with the development of molecular imaging, the development of EGFR-targeted molecular probes based on positron emission computed tomography-computed tomography (PET-CT) has made it possible to reveal the EGFR mutations in lung cancer tissues in vivo, and can detect the heterogeneity of EGFR mutations. This article reviews all the results and progress of molecular probes targeting EGFR mutations.

[Interaction between functional nano-hydroxyapatite and cells and the underlying mechanisms].

OBJECTIVE: To explore the interaction between arginine functionalized hydroxyapatite (HAP/Arg) nanoparticles and endothelial cells, and to investigate mechanisms for endocytosis kinetics and endocytosis.
 METHODS: Human umbilical vein endothelial cells (HUVECs) were selected as the research model.Cellular uptake of HAP/Arg nanoparticles were observed by laser scanning confocal microscopy.Average fluorescence intensity of cells after ingestion with different concentrations of HAP/Arg nanoparticles were determined by flow cytometer and atomic force microscopy.
 RESULTS: The HAP/Arg nanoparticles with doped terbium existed in cytoplasm, and most of them distributed around the nucleus area after cellular uptake by HUVECs. Cellular uptake process of HAP/Arg nanoparticles in HUVECs was in a time and concentration dependent manner. 4 h and 50 mg/L was the best condition for uptake. HAP/Arg nanoparticles were easier to be up-taken into the cells than HAP nanoparticles without arginine functionalized.
 CONCLUSION: HAP/Arg nanoparticles are internalized by HUVECs cells through an active transport and energy-dependent endocytosis process, and it is up-taken by cells mainly through caveolin-mediated endocytosis, but the clathrin-dependent endocytic pathway is also involved..

Tumor-specific expression of shVEGF and suicide gene as a novel strategy for esophageal cancer therapy.

AIM: To develop a potent and safe gene therapy for esophageal cancer. METHODS: An expression vector carrying fusion suicide gene (yCDglyTK) and shRNA against vascular endothelial growth factor (VEGF) was constructed and delivered into EC9706 esophageal cancer cells by calcium phosphate nanoparticles (CPNP). To achieve tumor selectivity, expression of the fusion suicide gene was driven by a tumor-specific human telomerase reverse transcriptase (hTERT) promoter. The biologic properties and therapeutic efficiency of the vector, in the presence of prodrug 5-fluorocytosine (5-FC), were evaluated in vitro and in vivo. RESULTS: Both in vitro and in vivo testing showed that the expression vector was efficiently introduced by CPNP into tumor cells, leading to cellular expression of yCDglyTK and decreased VEGF level. With exposure to 5-FC, it exhibited strong anti-tumor effects against esophageal cancer. Combination of VEGF shRNA with the fusion suicide gene demonstrated strong anti-tumor activity. CONCLUSION: The shVEGF-hTERT-yCDglyTK/5-FC system provided a novel approach for esophageal cancer-targeted gene therapy.

Boron neutron capture therapy for malignant melanoma: first clinical case report in China.

A phase I/II clinical trial for treating malignant melanoma by boron neutron capture therapy (BNCT) was designed to evaluate whether the world's first in-hospital neutron irradiator (IHNI) was qualified for BNCT. In this clinical trial planning to enroll 30 patients, the first case was treated on August 19, 2014. We present the protocol of this clinical trial, the treating procedure, and the clinical outcome of this first case. Only grade 2 acute radiation injury was observed during the first four weeks after BNCT and the injury healed after treatment. No late radiation injury was found during the 24-month follow-up. Based on positron emission tomography-computed tomography (PET/CT) scan, pathological analysis and gross examination, the patient showed a complete response to BNCT, indicating that BNCT is a potent therapy against malignant melanoma and IHNI has the potential to enable the delivery of BNCT in hospitals.

Dual-Modality Noninvasive Mapping of Sentinel Lymph Node by Photoacoustic and Near-Infrared Fluorescent Imaging Using Dye-Loaded Mesoporous Silica Nanoparticles.

The imaging of sentinel lymph nodes (SLNs), the first defense against primary tumor metastasis, has been considered as an important strategy for noninvasive tracking tumor metastasis in clinics. In this study, we developed an imaging contrast system based on fluorescent dye-loaded mesoporous silica nanoparticles (MSNPs) that integrate near-infrared (NIR) fluorescent and photoacoustic (PA) imaging modalities for efficient SLN mapping. By balancing the ratio of dye and nanoparticles for simultaneous optimization of dual-modality imaging (NIR and PA), the dye encapsulated MSNP platform was set up to generate both a moderate NIR emission and PA signals simultaneously. Moreover, the underlying mechanisms of the relevance between optical and PA properties were discovered. Subsequently, dual-modality imaging was achieved to visualize tumor draining SLNs up to 2 weeks in a 4T1 tumor metastatic model. Obvious differences in uptake rate and contrast between metastatic and normal SLNs were observed both in vivo and ex vivo. Based on all these imaging data, it was demonstrated that the dye-loaded MSNPs allow detection of regional lymph nodes in vivo with time-domain NIR fluorescent and PA imaging methods efficiently.

Down-regulation of phospho-non-receptor Src tyrosine kinases contributes to growth inhibition of cervical cancer cells.

Non-receptor Src tyrosine kinases (nrTKs) are overexpressed in a variety of human tumors, including cancer of the colon, breast, and pancreas, and their inhibitors are under intensive investigations as novel anti-tumor agents. However, these studies are not clear in the case of cervical cancer. Therefore, we studied the role of nrTKs and their inhibitors in the cervical cancer. The expression level of phospho-SrcY416 (pSrcY416) in several cervical cancer cell lines, normal cervical tissues, and cervical cancer tissues have been examined, and it has also been done whether PP2, an inhibitor of Src kinase, can inhibit the growth of cervical cells in vitro and in vivo. Immunohistochemical and confocal microscope studies suggested that pSrcY416 is overexpressed in HeLa and SiHa cells, as well as in the clinical cervical cancer tissues, compared to the normal cervical tissues. Down-regulation of pSrcY416 inhibited the cell proliferation by increasing the HeLa or SiHa cell population in the G0-G1 phase or S phase, respectively. Down-regulation of pSrcY416 led to up-regulation of p21Cip1 and p27Kip1 in both HeLa and SiHa cells and decreased the expression of cyclin A1, cyclin E, and cyclin-dependent kinase-2,-6 (CDK-2,-6) in HeLa cells and of cyclin B and CDK-2 in SiHa cells. Nude mice xenograft data showed that PP2 inhibited subcutaneous tumor growth significantly (P<0.05, compared with the control). Down-regulation of pSrcY416 contributes to cell growth inhibition in cervical cancer cells. nrTKs could therefore be a novel therapeutic targets for the treatment of cervical cancer.

Increased expression of heat shock protein 70 and heat shock factor 1 in chronic dermal ulcer tissues treated with laser-aided therapy.

BACKGROUND: Chronic dermal ulcers are also referred to as refractory ulcers. This study was conducted to elucidate the therapeutic effect of laser on chronic dermal ulcers and the induced expression of heat shock factor 1 (HSF1) and heat shock protein 70 (HSP70) in wound tissues. METHODS: Sixty patients with 84 chronic dermal ulcers were randomly divided into traditional therapy and laser therapy groups. Laser treatment was performed in addition to traditional therapy in the laser therapy group. The treatment efficacy was evaluated after three weeks. Five tissue sections of healing wounds were randomly collected along with five normal skin sections as controls. HSP70-positive cells from HSP70 immunohistochemical staining were counted and the gray scale of positive cells was measured for statistical analysis. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the mRNA and protein expressions of HSF1 and HSP70. RESULTS: The cure rate of the wounds and the total efficacy in the laser therapy group were significantly higher than those in the traditional therapy group (P < 0.05, P < 0.01, respectively). Immunohistochemical staining revealed that the HSP70-positive cell count was significantly higher in laser therapy group than those in the traditional therapy group and controls (P < 0.01), and the gray scale of the cell signal was obviously lower than traditional therapy group and controls (P < 0.05). By contrast, the traditional therapy group and the control group were not significantly different. The RNA levels of HSF1 and HSP70 were higher in the laser therapy group by RT-PCR, but very low in normal skin and the traditional therapy group. The analysis on the gray scale of the Western blot bands indicated that the expression of HSF1 and HSP70 in the laser therapy group was significantly higher than in the traditional therapy group and the control group (P < 0.01), and the expression in the traditional therapy group was also higher than in the control group (P < 0.05). CONCLUSION: Laser-aided therapy of chronic dermal ulcers plays a facilitating role in healing due to the mechanism of laser-activated endogenous heat shock protection in cells in wound surfaces.

[Study on biocompatibility of hydroxyapatite/high density polyethylene (HA/HDPE) nano-composites artificial ossicle].

This study was aimed to evaluate the biocompatibility of Hydroxyapatite/High density polyethylene (HA/ HDPE) nano-composites artificial ossicle. The percentage of S-period cells were detected by flow cytometry after L929 cells being incubated with extraction of the HA/HDPE nano-composites; the titanium materials for clinical application served as the contrast. In addition, both materials were implanted in animals and the histopathological evaluations were conducted. There were no statistically significant differences between the two groups (P >0.05). The results demonstrated that the HA/HDPE nano-composite artificial ossicle made by our laboratory is of a good biocompatibility and clinical application outlook.

[Study on biocompatibility of MIM 316L stainless steel].

This study was aimed to evaluate the biocompatibility of metal powder injection molding (MIM) 316L stainless steel. The percentage of S-period cells was detected by flow cytometry after L929 cells being incubated with extraction of MIM 316L stainless steel, and titanium implant materials for clinical application were used as control. In addition, both materials were implanted in animals and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between the two groups (P > 0.05), which demonstrate that MIM 316L stainless steel has good biocompatibility.

High-level expression, one-step purification of soluble Ad5-knob protein and its activity assay.

This report describes a simple, highly efficient, and reproducible method for obtaining large quantities of highly pure recombinant Ad5-knob protein, which can be used for gene-delivery application. The Ad5- knob protein expressed in Escherichia coli contained a His tag at the N-terminus that allowed one-step isolation by immobilized metal affinity chromatography (IMAC). The activity of the recombinant protein was tested by receptor-binding assay in Hela cells for potential application in gene delivery.

Sodium chloride modified silica nanoparticles as a non-viral vector with a high efficiency of DNA transfer into cells.

Development of reliable vectors is a major challenge in gene therapy. Previous gene transfer methods using non-viral vectors, such as liposomes or nanoparticles, have resulted in relatively low levels (35 to approximately 50%) of gene expression. We have developed a silicon nanoparticle (SNAP) system, a novel non-viral vector, for DNA transfer into cells. SNAP was synthesized chemically and modified with sodium chloride or sodium iodide. Electronmicroscopy of SNAP and fluorescence microscopy of fluorescence-labeled SNAP revealed that they were generated uniformly, had diameters of 10-100 nm, and showed a better efficiency (about 70%) of DNA transfection into cells as well as protection of DNA against degradation. The microscopy also demonstrated the adhesion of SNAP with HT1080 cell surface and entry of SNAP into the cells without cytotoxicity. Intravenous and/or intra-abdominal administration of the SNAP to mice revealed the accumulation of SNAP in the cells of the brain, liver, spleen, lung, kidney, intestine, prostate and the testis without any pathological cell changes or mortality, suggesting that they passed through the blood-brain, blood-prostate, and blood-testis barriers. These findings indicate that the SNAP generated has good biological characteristics as a potential promising vector for gene transfer, gene therapy and drug delivery.