Blockade of experimental atopic dermatitis via topical NF-kappaB decoy oligonucleotide.

Atopic dermatitis (AD) is a common chronic skin inflammatory disease. Long-term use of topical corticosteroids in skin inflammation poses risks of systemic and local side effects. The NF-kappaB transcription factor family plays a central role in the progression and maintenance of AD. This study explores the possibility of using topical NF-kappaB Decoy as a novel therapeutic alternative for targeting Th1/Th2-driven skin inflammation in experimental AD. A high-affinity, topical NF-kappaB Decoy developed for human efficacy demonstrates: (i) efficient NF-kappaB Decoy penetration in pig skin, (ii) NF-kappaB Decoy nuclear localization in keratinocytes and key immune cells, and (iii) potent "steroid-like" efficacy in a chronic dust-mite antigen skin inflammation treatment model. NF-kappaB Decoy exerts its anti-inflammatory action through the effective inhibition of essential regulators of inflammation and by induction of apoptosis of key immune cells. Unlike betamethasone valerate (BMV), long-term NF-kappaB Decoy treatment does not induce skin atrophy. Moreover, topical NF-kappaB Decoy, in contrast to BMV, restores compromised stratum corneum integrity and barrier function. Steroid withdrawal causes rapid rebound of inflammation, while the NF-kappaB Decoy therapeutic benefit was maintained for weeks. Thus, topical NF-kappaB Decoy provides a novel mechanism of reducing chronic skin inflammation with improved skin homeostasis and minimal side effects.

Standardized cryopreservation of pluripotent stem cells.

The successful exploitation of human cells for research, translational, therapeutic, and commercial purposes requires that effective and simple cryopreservation methods be applied for storage in local and master cell banks. Of all the cell types utilized in modern research, human embryonic stem cells and their more recent relatives, induced pluripotent stem cells, are two of the most sensitive to cryopreservation. It is frequently observed that the lack of quality control and proper processing techniques yield poor recovery of pluripotent stem cells. The procedures in this unit have been optimized for handling some of the most recalcitrant stem cell lines, and provide a method for controlled-rate freezing, using minimal equipment that affords levels of cell viability comparable to expensive controlled-rate freezers. The protocol also eliminates the requirement for isopropanol, avoiding the hazards, on-going cost, and inconsistencies associated with its use and disposal. It provides a clinically relevant, inexpensive, reliable, and user-friendly method that successfully prepares cells for long-term cold storage and ensures maximum levels of cell viability post thaw.

Non-viral delivery of nuclear factor-kappaB decoy ameliorates murine inflammatory bowel disease and restores tissue homeostasis.

BACKGROUND: Nuclear factor-kappaB (NF-kappaB) is a key transcriptional regulator of inflammatory bowel disease (IBD). AIM: To investigate the therapeutic potential of a locally administered "non-viral" nuclear factor-kappaB decoy (NFkappaBD) in multiple experimental models of IBD. METHODS: A fully phosphorothioated decoy oligonucleotide with improved stability that specifically binds NF-kappaB and blocks inflammatory mediators regulated by this transcription factor without the help of viral envelope-assisted delivery was developed. The therapeutic effects of NFkappaBD were studied in the trinitrobenzene sulphonic acid, oxazolone and dextran sodium sulphate induced colitis models. RESULTS: Intracolonic administration of NFkappaBD results in the delivery of NFkappaBD to inflammatory cells and a reduction of NF-kappaB heterodimers. In the T helper cell 1-driven trinitrobenzene sulphonic acid-induced colitis model, mice receiving NFkappaBD treatment exhibit a dose-dependent reduction in disease severity and a more rapid recovery to normal body weight, similar to a clinically relevant dose of budesonide. Clinical efficacy was corroborated by considerable reductions in colitis pathology and tissue levels of several pro-inflammatory markers, including tumour necrosis factor alpha, interleukin 6, interleukin 1beta and monocyte chemotactic protein 1. NFkappaBD also mitigates disease activity in the T helper cell 2-like oxazolone colitis and epithelial injury-related acute dextran sodium sulphate colitis models. Interestingly, restoration of tissue homeostasis is observed in NFkappaBD-treated animals with the rapid re-emergence of functional goblet cells and a return to normal patterns of cell proliferation in the mucosal epithelium and smooth muscle cell layers. CONCLUSIONS: These data support the potential use of "naked" NFkappaBD as a cross-functional therapeutic in IBD, and show for the first time that it can facilitate the restoration of colon homeostasis and function.

Requirement for PAK4 in the anchorage-independent growth of human cancer cell lines.

p21-activated protein kinase (PAK) serine/threonine kinases are important effectors of Rho family GTPases and have been implicated in the regulation of cell morphology and motility, as well as in cell transformation. To further investigate the possible involvement of PAK kinases in tumorigenesis, we analyzed the expression of several family members in tumor cell lines. Here we demonstrate that PAK4 is frequently overexpressed in human tumor cell lines of various tissue origins. We also have identified serine (Ser-474) as the likely autophosphorylation site in the kinase domain of PAK4 in vivo. Mutation of this serine to glutamic acid (S474E) results in constitutive activation of the kinase. Phosphospecific antibodies directed against serine 474 detect activated PAK4 on the Golgi membrane when PAK4 is co-expressed with activated Cdc42. Furthermore, expression of the active PAK4 (S474E) mutant has transforming potential, leading to anchorage-independent growth of NIH3T3 cells. A kinase-inactive PAK4 (K350A,K351A), on the other hand, efficiently blocks transformation by activated Ras and inhibits anchorage-independent growth of HCT116 colon cancer cells. Taken together, our data strongly implicate PAK4 in oncogenic transformation and suggest that PAK4 activity is required for Ras-driven, anchorage-independent growth.