AAF-cmk sensitizes tumor cells to trail-mediated apoptosis

Human Beta Defensin-2 mRNA and Proteasome Subunit β Type 8 mRNA Analysis, Useful in Differentiating Skin Biopsies from Atopic Dermatitis and Psoriasis Vulgaris Patients

(1): Atopic dermatitis and psoriasis vulgaris are chronic, inflammatory diseases. Clinical presentation usually leads to a proper diagnosis, but sometimes neither clinical examination nor histopathological evaluation can be conclusive. Therefore, we aimed to build up a novel diagnostic tool and check it for accuracy. The main objective of our work was to differentiate between healthy skin (C), atopic dermatitis (AD) and psoriasis vulgaris (PV) biopsies on the base of involucrin (IVL) and human β-defensin-2 (hBD-2) concentrations and their mRNA, as well as mRNA for TPP2 and PSMB8. (2): ELISA for IVL and hBD-2 proteins and Real-time PCR for the relative expression of mRNA for: IVL (IVL mRNA), hBD-2 (hBD-2 mRNA), PSMB8 (PSMB8 mRNA) and TPP2 (TPP2 mRNA), isolated from skin biopsies taken from AD and PV patients and healthy volunteers were performed. (3): hBD-2 mRNA and PSMB8 mRNA correlated with some parameters of clinical assessment of inflammatory disease severity. hBD-2 mRNA expression, exclusively, was sufficient to distinguish inflammatory skin biopsies from the healthy ones. (4): hBD-2 mRNA and PSMB8 mRNA analysis were the most valuable parameters in differentiating AD and PV biopsies.

New gold (III) cyanide complex TGS 121 induces ER stress, proteasome inhibition and death of Ras-hyperactivated cells

Metal-based agents in cancer therapy, like cisplatin and its derivates, have established clinical applications but also can induce serious side effects. Thus, metallotherapeutic alternatives for platinum derivatives are developed and intensively studied. Platinum is replaced by several transition metals including gold. Especially gold (III) complexes can have the same square-planar structure and are isoelectric with platinum (II). Hence, they are developed as potential anti-cancer drugs. Thus, our group projected and developed a group of novel cyanide-based gold (III) complexes. Within this work, we aimed to characterize the safety and effectivity of one of them, TGS 121. TGS 121 in our preliminary work was selective for Ras-hyperactivated cells. Here we studied the effects of the novel complex in cancerous Ras-3 T3 and non-cancerous NIH-3 T3 cells. The complex TGS 121 turned out to be non-toxic for NIH-3 T3 cells and to induce death and alternations in Ras-hyperactivated cells. We found induction of ER stress, mitochondria swelling, proteasome inhibition, and cell cycle block. Moreover, TGS 121 inhibited cell migration and induced the accumulation of perinuclear organelles that was secondary to proteasome inhibition. Results presented in this report suggest that stable gold-cyanide TGS 121 complex is non-toxic, with a targeted mechanism of action and it is promising in anticancer drug discovery.

Novel podophyllotoxin and benzothiazole derivative induces transitional morphological and functional changes in HaCaT cells

Podophyllotoxin (PPT) is an antimitotic drug used topically in the treatment of anogenital warts. Due to its toxicity it cannot be administered systemically as an anticancer agent. However, modified PPT derivatives such as etoposide and teniposide are used clinically as systemic agents. Thus, we invented novel PPT derivative KL3 that was synthesized by photocyclization. Earlier we have shown that KL3 has an anticancer effect in various cell lines. Here we compared the toxicity of KL3 vs PPT on non-cancerous normal human keratinocytes (HaCaT) and peripheral blood mononuclear cells (PBMC) showing that KL3 is less toxic than PPT to non-cancerous cells. At concentrations that neither induced cell death, nor affected cell cycle, KL3 in HaCaT cells evoked transient ultrastructural features of ER stress, swelling of mitochondria and elongation of cytoplasmic processes. Those changes partially reversed with prolonged incubation while features of autophagy were induced. PPT in equivalent concentrations induced HaCaT cell death by cell cycle arrest, intrinsic apoptosis and finally disintegration of cell membranes followed by secondary necrosis. In conclusion, we show that the KL3 derivative of PPT in contrast to PPT allows repair of normal keratinocytes and triggers mechanisms that restore non-tumor cell homeostasis.

Proteases implicated in apoptosis: old and new

OBJECTIVES

The role of proteases in the regulation of apoptosis is becoming increasingly apparent. Whilst many of these proteases are already characterised, some have yet to be identified. Traditionally caspases held the traditional role as the prime mediators of apoptosis; however, attention is now turning towards the contribution made by serine proteases.

KEY FINDINGS

As unregulated apoptosis is implicated in various disease states, the emergence of this proteolytic family as apoptotic regulators offers novel and alterative opportunities for therapeutic targets.

SUMMARY

This review presents a brief introduction and overview of proteases in general with particular attention given to those involved in apoptotic processing.