Background: The purpose of this study was to develop a nanoplatform, which simultaneously acts as radiosensitizer, drug carrier, and tumor imaging agent for head and neck cancer.
Methods: We synthesized 20 nm gold nanoparticles, coated with glucose and cisplatin (CG-GNPs). Their penetration into tumor cells and their cellular toxicity were evaluated in vitro.
DNA damage and repair are linked to fundamental biological processes such as metabolism, disease, and aging. Single-strand lesions are the most abundant form of DNA damage; however, methods for characterizing these damage lesions are lacking. To avoid double-strand breaks and genomic instability, DNA damage is constantly repaired by efficient enzymatic machinery.
View Article and Find Full Text PDFThe oncogenic nature ascribed to the PIM-2 kinase relies mostly on phosphorylation of substrates that act as pro-survival/anti-apoptotic factors. Nevertheless, pro-survival effects can also result from activating DNA repair mechanisms following damage. In this study, we addressed the possibility that PIM-2 plays a role in the cellular response to UV damage, an issue that has never been addressed before.
View Article and Find Full Text PDFThe organotellurium compound, AS101, induces G(2)/M growth arrest and apoptosis in multiple myeloma (MM) cell lines. To characterize the mechanism by which AS101 promotes these effects, an antibody microarray analysis was performed, comparing levels of proteins and phosphoproteins in untreated versus AS101-treated mouse 5T33 MM cells. We found that AS101 down-regulated Ilk-1, Cdc25C and phosphorylation of Plk-1 on Thr210, all of which can affect the onset of mitosis or cell survival.
View Article and Find Full Text PDFPotent survival effects have been ascribed to the serine/threonine kinase proto-oncogene PIM-2. Elevated levels of PIM-2 are associated with various malignancies. In human cells, a single Pim-2 transcript gives rise mainly to two protein isoforms (34, 41 kDa) that share an identical catalytic site but differ at their N-terminus, due to in-frame alternative translation initiation sites.
View Article and Find Full Text PDFWe report here an outbreak of an acute disease that caused high mortality rate in laboratory-reared tilapia larvae. The disease was initially observed in inbred gynogenetic line of blue tilapia larvae (Oreochromis aureus) and could be transmitted to larvae of other tilapia species. Based on the clinical manifestation (a whirling syndrome), we refer to the disease as viral encephalitis of tilapia larvae.
View Article and Find Full Text PDFMeig1 is a mouse gene, abundantly expressed in the testis. It encodes two alternative transcripts that are expressed differentially in the somatic and germinal compartments of the testis. These transcripts share the same coding region but differ in their 5' un-translated regions, due to alternative promoters.
View Article and Find Full Text PDFMicroarray technology which enables large scale analysis of gene expression and thus comparison between transcriptomes of different cell types, cells undergoing different treatments or cells at different developmental stages has also been used to study the transcriptome involved with spermatogenesis. Many new germ cell-specific genes were determined, and the resulting genes were classified according to different criteria. However, the biological significance of these classifications and their clustering according to developmental transcriptional patterns during spermatogenesis have not yet been addressed.
View Article and Find Full Text PDFMSP is a male-specific protein initially identified in the serum of sexually active Sarotherodon galilaeus males, and is shown herein to be present in the serum of sexually mature males, but not females, of three other tilapia species. Cloning of the MSP cDNA and analysis of its predicted amino-acid sequence revealed that it is an outlier lipocalin that contains a signal peptide in its N-terminal region. The abundance of highly homologous sequences found in fish and the monophyletic relationship to tetrapod Alpha-1-acid glycoprotein (AGP) places it as a clade XII lipocalin.
View Article and Find Full Text PDFAtce1 belongs to the CREB3/LZIP subtype of the ATF/CREB transcription factor gene family. Its transcription has previously been shown to be testis-specific and within the testis to be restricted to haploid spermatids. In this study, we characterized the protein's distribution in the testis and found that it accumulates in late round and in elongating spermatids, corresponding to developmental stages considered transcriptionally silent.
View Article and Find Full Text PDFMultiple Myeloma (MM) is a clonal B-cell malignancy affecting both the immune and the skeletal systems, and accounts for 10% of all hematological cancers. The immunomodulator ammonium trichloro (dioxoethylene-O,O') tellurate (AS101) is a non-toxic compound which has direct anti-tumoral properties in several tumor models. The present study examined the anti-tumoral activity of AS101 in MM by targeting the Akt/Survivin signaling pathway, crucial for survival.
View Article and Find Full Text PDFOur understanding of the molecular mechanisms that operate during differentiation of mitotically dividing spermatogonia cells into spermatocytes lags way behind what is known about other differentiating systems. Given the evolutionary conservation of the meiotic process, we screened for mouse proteins that could specifically activate early meiotic promoters in Saccharomyces cerevisiae yeast cells, when fused to the Gal4 activation domain (Gal4AD). Our screen yielded the Aym1 gene that encodes a short peptide of 45 amino acids.
View Article and Find Full Text PDFPim-1 and Pim-2 are murine proto-oncogenes implicated in lymphomagenesis. The aim of this study was to investigate whether the human Pim-2 (hPim-2) expression is altered in chronic lymphocytic leukemia (B-CLL) and non-Hodgkin's lymphomas (NHL). We analyzed hPim-2 expression in 48 patients with NHL and CLL by quantitative in-situ hybridization, quantitative RT-PCR and FACS analysis.
View Article and Find Full Text PDFMol Cell Endocrinol
February 2002
One of the molecular mechanisms shown to have played a major role in orchestrating the expression of the many genes with unique cellular and temporal specificity in spermatogenesis, is the cAMP-dependent signaling pathway. In this pathway, gene expression is mediated primarily by two members of the bZIP transcription factors-cAMP-response element binding protein (CREB) and cAMP-responsive element modulator (CREM). Both bind a specific cis element, cAMP-response element (CRE), in the promoter of target genes, both are activated by protein kinase A (PKA) phosphorylation that enables binding of CREB binding protein (CBP) and recruitment of the basal transcription machinery, and both are characterized by multiple alternatively spliced forms.
View Article and Find Full Text PDFMembers of the ATF/CREB family of transcription factors are involved in gene activation in various physiological systems ranging from metabolite homeostasis, through regulation of cell cycle, to learning and memory. Two members of this family, cAMP-responsive element binding protein (CREB), and cAMP-responsive element modulator (CREM) are active during mammalian spermatogenesis and are required for this process, as has been shown by knockout and dominant negative experiments. In an effort to identify mouse proteins that interact with the testis-specific protein Tctex2, a mouse testis expression library was screened via the two-hybrid system, using the carboxyl-terminal portion of this protein as bait.
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