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Polymeric materials are in the epicenter of scientific research the last decade and have been used in a range of pharmaceutical and biological applications. Multifunctional polymeric materials are capable targeting agents, which can be used as controlled drug release vehicles for the enhancement of therapeutic efficacy, as well as for diagnostic purposes. A newer generation of these smart polymeric entities constitutes of smart nanocontainers (NCs), which can navigate the drug to specific areas by avoiding random distribution, and thus resulting in drug toxicity reduction. The combination of pH, thermo and redox sensitivity of the multi stimuli NCs can help to achieve specific release of the drug in the tumor area, where these sensitivity parameters can be observed. Hollow polymeric multi stimuli fluorescent tNCs based on N-(2-Hydroxypropyl)methacrylamide (HPMA) were successfully functionalized with a specific targeting moiety; folic acid, and then characterized morphologically, by scanning electron and transmission electron microscopy, as well as structurally, by Fourier-transform infrared spectroscopy. Their targeting mechanism was investigated in vitro in cervical cancer cell lines and in vivo in tumor bearing mice. According to our results the folic acid functionalized NCs targeted HeLa cells’ surface within the first 30 min of treatment. Human tumor xenografted mice (nonobese diabetic/severe combined immunodeficient) were injected with folate functionalized NCs and their tumor uptake was estimated by γ-imaging at about 3.5%. The targeting efficiency of the folate functionalized NCs was investigated directly in vivo by γ-imaging and indirectly by a tumor efficacy protocol.

We have identified a novel mouse gene encoding a protein that shows high homology to the dual-specificity tyrosine/threonine phosphatase family of proteins. The gene encodes a 5 kb transcript which is expressed predominantly in brain and lung and contains a translated complex trinucleotide repeat within the coding region. Using interspecific mouse backcross analysis, the gene has been localised to distal mouse chromosome 7. In human, homologous sequences are located in the syntenic region on distal chromosome 11p as well as to chromosome 10q11.2 and 10q22. The presence of a CG-rich trinucleotide repeat in the coding region provides a target for mutation which might result in loss of function or altered properties of this phosphatase.

We have identified Ngef as a novel member of the family of Dbl genes. Many members of this family have been shown to function as guanine nucleotide exchange factors for the Rho-type GTPases. Ngef is predominantly expressed in brain, with the strongest signal in the caudate nucleus, a region associated with the control of movement. Ngef contains a translated trinucleotide repeat, a polyglutamic acid stretch interrupted by a glycine. We have localized the Ngef gene to mouse chromosome 1 and the human homologue of Ngef to human chromosome 2q37. We have shown in preliminary experiments that Ngef has transforming potential in cell culture and is able to induce tumors in nude mice.

Mitogen-activated protein kinase phosphatases (MKPs) play a central role in a variety of signaling pathways. We recently described a novel murine MKP, M3/6, which is uniquely specific for c-Jun N-terminal kinase/stress-activated protein kinase and p38 kinase. Here we report the localization of the human orthologue of this gene, HB5, to within 150 kb of H19 on human chromosome 11p15.5. The gene consists of six exons. Two of the introns in HB5 are not found in other genes of this family, suggesting an evolutionary split between MKPs displaying specificity toward different MAP kinases. An intronless pseudogene is present on chromosome 10q11.2. Although 11p15.5 is an imprinted region, HB5 is almost entirely unmethylated on both alleles in lymphocytes. Chromosome 11p15 has been implicated in the development of a number of tumor types, including lung, a tissue known to express this gene. Loss of heterozygosity was found in one of eight informative lung tumors studied.

The Survival Motor Neuron (SMN) gene shows deletions in the majority of patients with Spinal Muscular Atrophy (SMA), a disease of motor neuron degeneration. To date only two missense mutations have been reported in SMN in patients with SMA. The fact that no SMN-homologues have been forthcoming from database searching has resulted in a lack of hypotheses concerning the structural and functional consequences of these mutations. Recently SMN has been shown to interact with heterogeneous nuclear ribonu-cleoproteins (hnRNPs) suggesting a role in mRNA metabolism. We describe a novel missense mutation and the subsequent identification of a triplicated tyrosine-glycine (Y-G) peptide sequence at the C-terminal of SMN which encompasses each of the three predicted amino acid sequence substitutions. We have identified apparent orthologues of SMN in Caenorhabditis elegans and Schizosaccharomyces pombe. These sequences retain the highly conserved Y-G motif and provide additional support for a role of SMN in mRNA metabolism.