A novel fluorescent dye selectively images and kills cancer stem cells by targeting mitochondria: Evidence from a cell line­based zebrafish xenograft model.

Numerous agents such as near-infrared dyes that are characterized by specialized cancer imaging and cytotoxicity effects have key roles in cancer diagnosis and therapy via molecularly targeting special biological tissues, organelles and processes. In the present study, a novel fluorescent compound was demonstrated to inhibit cancer cell proliferation in a zebrafish model with slight in vivo toxicity. Further studies demonstrated selective staining of cancer cells and even putative cancer stem cells via accumulation of the dye in the mitochondria of cancer cells, compared with normal cells. Moreover, this compound was also used to image cancer cells in vivo using a zebrafish model. The compound displayed no apparent toxicity to the host animal. Overall, the data indicated that this compound was worthy of further evaluation due to its low toxicity and selective cancer cell imaging and killing effects. It could be a useful tool in cancer research.

Gambogic acid suppresses nasopharyngeal carcinoma via rewiring molecular network of cancer malignancy and immunosurveillance.

Nasopharyngeal carcinoma (NPC) is a malignant tumor highly prevalent in Southeast Asia. The distant metastasis and disease recurrence are still unsolved clinical problems. In recent years, traditional Chinese medicine (TCM) monomers have become significantly attractive due to their advantages. Using high throughput drug sensitivity screening, we identified gambogic acid (GA) as a common TCM monomer displaying multiple anti-NPC effects. GA could effectively inhibit the proliferation of low differentiated cells and highly metastatic cells in NPC via inducing apoptosis and G2/M cell cycle arrest. In addition, GA obviously repressed the abilities of cell clone, migration, invasion, angiogenesis and represented satisfied synergistic effects combined with chemotherapy. Importantly, we found the elevated immune checkpoint CD47 stimulated after chemotherapy was dramatically impaired by GA treatment. Mechanically, the network pharmacology analyses unraveled that the oncogenic signaling pathways including STATs were rewired by GA treatment. Taken together, our study reveals a molecular basis and provides a rationale for GA application as the treatment regime in NPC therapy in future.

A Novel Fluorescent Dye Invades Mitochondria to Selectively Kill Cancer Stem Cells via Increased ROS Production.

Development of multiple agents has a significant impact on the cancer diagnosis and therapy. Several fluorescent dyes including near-infrared (NIR) fluorescent agents have been already well studied in the field of photodynamic therapy (PDT). In the present study, we reported a novel fluorescent dye could obviously inhibit cancer cell proliferation with slight toxic effects on the biological organism. Furthermore, it displayed selective staining on cancer cells, particularly on cancer stem cells (CSCs), rather than normal cells. Mechanically, this dye preferred to invading mitochondria of cancer cells and inducing overwhelming reactive oxygen species (ROS) production. The in vivo experiments further demonstrated that this dye could image cancer cells and even CSCs in a short-time intratumor injection manner using a zebrafish model and subsequently inhibit cancer cell proliferation after a relatively long-time drug exposure. Taken together, the future development of this agent will promise to make an essential contribution to the cancer diagnosis and therapeutics.

S100A8/A9 Molecular Complexes Promote Cancer Migration and Invasion via the p38 MAPK Pathway in Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is one type of malignancy associated with migration and invasion through a currently unclear mechanism. We previously discovered S100A8/A9 levels were roughly elevated in the plasma of NPC patients as the promising biomarkers. However, their expressions and underlying functions in NPC tissues are still unknown. In the present study, we analyzed 49 NPC tissues and 20 chronic pharyngitis (CP) tissues. Immunohistochemical staining was performed in different tissues and analyzed by the Mann-Whitney U test statistically. Transwell migration and invasion experiments were further performed to determine S100A8/A9 effects on NPC. Our results showed that S100A8/A9 in NPC tissues were significantly higher than those in CP tissues, closely associated with NPC clinical stages. Intriguingly, exogenous S100A8/A9 protein stimulation could dramatically enhance NPC migration and invasion abilities. In addition, p38 MAPK pathway blockade could diminish the migration and invasion of NPC cells stimulated by S100A8/A9 proteins. The downstream tumor invasion and migration associated proteins (e.g., MMP7) were also elevated in NPC tissues, consistent with S100A8/A9 overexpression. Taken together, our present findings suggest that the secreted soluble inflammatory factors S100A8/A9 might promote cancer migration and invasion via the p38 MAPK signaling pathway along with invasion/migration associated proteins overexpression in the tumor microenvironment of NPC. This may shed light on the mechanism understanding of NPC prognosis and provide more novel clues for NPC diagnosis and therapy.

Network Pharmacology Reveals Polyphyllin II as One Hit of Nano Chinese Medicine Monomers against Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is a malignant tumor in southern China, and nano Traditional Chinese Medicine (TCM) represents great potential to cancer therapy. To predict the potential targets and mechanism of polyphyllin II against NPC and explore its possibility for the future nano-pharmaceutics of Chinese medicine monomers, network pharmacology was included in the present study. Totally, ninety-four common potential targets for NPC and polyphyllin II were discovered. Gene Ontology (GO) function enrichment analysis showed that biological processes and functions mainly concentrated on apoptotic process, protein phosphorylation, cytosol, protein binding, and ATP binding. In addition, the anti-NPC effects of polyphyllin II mainly involved in the pathways related to cancer, especially in the PI3K-Akt signaling indicated by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The "drug-target-disease" network diagram indicated that the key genes were SRC, MAPK1, MAPK14, and AKT1. Taken together, this study revealed the potential drug targets and underlying mechanisms of polyphyllin II against NPC through modern network pharmacology, which provided a certain theoretical basis for the future nano TCM research.

Effects of silencing S100A8 and S100A9 with small interfering RNA on the migration of CNE1 nasopharyngeal carcinoma cells.

The calcium-binding S100 proteins are involved in functions such as cell growth, differentiation, migration, adhesion and signal transduction. S100A8 and S100A9 are highly expressed in a variety of tumor cells, and are implicated in tumor development and progression. However, the role of S100A8 and S100A9 in nasopharyngeal carcinoma (NPC) cell migration is unclear. The present study investigated the effect of S100A8 and S100A9 on migration using a NPC cell line, CNE1. The CNE1 cells were transfected with S100A8 or S100A9 small interfering RNA (siRNA). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect S100A8 and S100A9 gene expression. Following the downregulation of S100A8 or S100A9, the effects on cell migration were determined using wound-healing assays. The expression of matrix metalloproteinase-7 (MMP7), a member of the MMP family that is associated with tumor cell invasion and migration, was also detected by RT-qPCR. S100A8 and S100A9 siRNAs effectively suppressed S100A8 and S100A9 gene expression, and substantially inhibited the migration of the CNE1 cells. In addition, MMP7 expression was reduced to varying extents in S100A8 and S100A9 siRNA-treated cells compared with controls. Thus, S100A8 and S100A9 promoted the migration of CNE1 NPC cells.

Nitrative and oxidative DNA damage as potential survival biomarkers for nasopharyngeal carcinoma.

Currently, there are no satisfactory biomarkers available to screen for nasopharyngeal carcinoma (NPC). Nitric oxide (NO), produced by inducible nitric oxide synthase (iNOS), has been suggested to cause nitrative and oxidative stress, leading to the accumulation of 8-nitroguanine (8-NitroG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the subsequent transversion mutation of DNA. The aim of this study was to evaluate iNOS expression and the status of nitrative and oxidative stress in NPC. Fifty-nine cases of NPC and 39 cases of chronic nasopharyngitis were investigated to examine the expression of iNOS and the formation of 8-NitroG and 8-OHdG, using double-immunofluorescent staining. The statistical differences in immunoreactivities were analyzed using the Mann-Whitney test. Thirty-six patients from the 57 cases of NPC and 36 healthy controls were investigated to examine the level of serum 8-OHdG, using enzyme-linked immunosorbent assay (ELISA). The statistical differences were analyzed using a t test. Strong DNA lesions were observed in the cancer cells of NPC patients. All cases of NPC were positive for 8-NitroG and 8-OHdG, and 54 (94.7%) were positive for iNOS. NPC samples exhibited significantly more intense staining for 8-NitroG, 8-OHdG and iNOS than those of chronic nasopharyngitis (P < 0.05, respectively). The mean value of serum 8-OHdG in the 36 NPC patients was 0.538 ± 0.336 ng/ml compared to 0.069 ± 0.059 ng/ml for the healthy controls. The difference in the serum levels of 8-OHdG between the NPC patients and controls was statistically significant (P < 0.05). Our present findings suggest that pathological stimulation of nasopharyngeal tissue, caused by bacterial, viral or parasitic inflammation, may lead to nitrative and oxidative DNA lesions, caused by NO. This may contribute to the cause and development of NPC. Thus, 8-NitroG and 8-OHdG could be potential biomarkers for evaluating the risk of NPC. Better understanding of the molecular mechanisms underlying nitrative and oxidative DNA damage may provide clues to molecular targets for new approaches of NPC prevention.

Comparison of protein profiles between acetonitrile- and non-acetonitrile-treated sera from patients with nasopharyngeal carcinomas.

Serum proteins may be abnormally increased or decreased during the occurrence and development of nasopharyngeal carcinoma (NPC). However, currently there are no simple or effective methods to collect and differentiate these abnormally secreted proteins from abundant serum proteins. In this study, acetonitrile was used to remove the majority of high-abundance proteins from serum samples obtained from patients with NPC. The samples were subjected to surface-enhanced laser desorption/ionization time-of-flight mass spectrometry with a CM10 (weak cation exchange) ProteinChip, and the resulting protein profiles were compared with those of non-acetonitrile-treated serum samples. The results showed that the protein profiles differed between the acetonitrile- and non-acetonitrile-treated sera from patients with NPC. A large proportion of the non-acetonitrile-treated NPC serum protein peaks were <6000 kDa, while the detection rate of protein peaks >6000 kDa was relatively higher in the acetonitrile-treated NPC sera, accounting for more than half of all protein peaks (26.2+37.5%). Few differentially upregulated proteins were lost, and the peak value density increased after acetonitrile treatment. In conclusion, acetonitrile treatment of serum samples is effective in removing high-abundance macromolecular proteins. Therefore, acetonitrile treatment can be applied for the investigation of serum proteomics and may aid in the identification of differentially expressed proteins.

SELDI-TOF MS profiling of serum for detection of nasopharyngeal carcinoma.

BACKGROUND: No satisfactory biomarkers are currently available to screen for nasopharyngeal carcinoma (NPC). We have developed and evaluated surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) for detection and analysis of multiple proteins for distinguishing individuals with NPC from control individuals. METHODS: A preliminary learning set and a classification tree of spectra derived from 24 patients with NPC and a group of 24 noncancer controls were used to develop a proteomic model that discriminated cancer from noncancer effectively. Then, the validity of the classification tree was challenged with a blind test set, which included another 20 patients with NPC and 12 noncancer controls. RESULTS: A panel of 3 biomarkers ranging m/z 3-20 k was selected to establish Decision Tree model by BPS with sensitivity of 91.66% and specificity of 95.83%. The ability to detect NPC patients was evaluated, a sensitivity of 95.0% and specificity of 83.33% were validated in blind testing set. CONCLUSION: This high-flux proteomic classification system will provide a highly accurate and innovative approach for the detection/diagnosis of NPC.

Genome mapping and gene analysis of Antheraea pernyi nucleopolyhedrovirus for improvement of baculovirus expression vector system.

We have constructed a genome DNA map of the Antheraea pernyi nucleopolyhedrovirus (AnpeNPV) and used it to identify target genes for deletion in order to improve the newly developed baculovirus expression vector system. Initially, 50 independent PstI fragments of viral DNA were obtained by shotgun cloning, and both termini of each cloned fragment were sequenced. Then, the sequence data were used for homology search against both nucleotide and amino acid sequences of other NPVs in databases. This homology search allowed us to construct a nearly complete restriction map of a viral DNA with several assumed gaps. Four additional PstI fragments covering the gaps were obtained by PCR amplification, and a complete map of a circular viral DNA, which consisted of 54 PstI fragments, was constructed. The map indicated that the AnpeNPV genome is approximately 130.2 kbp in size and possesses high similarity to the Orgyia pseudotsugata multicapsid NPV (OpMNPV) genome in both sequence and arrangement of genes. Utilizing the genome-wide high similarity between AnpeNPV and OpMNPV, we identified two target genes on the map, namely, cathepsin and chitinase genes, whose products have been proved to be involved in the degradation of recombinant proteins and the liquefaction of virus-infected insect tissues. Comparative sequence analysis of the map also revealed the lack of certain OpMNPV open reading frame (ORF) homologs and the presence of ORFs, whose homologs do not exist in OpMNPV but in other group I NPVs, providing an insight into the position of AnpeNPV in the baculovirus phylogeny.