Biomedical subjects

Jan Maschke

Publications and source records attributed to Jan Maschke.

5 recordsLinked to original sources

PubMed2004

[Imiquimod for the topical treatment of focal epithelial hyperplasia (Heck disease) in a child].

Focal epithelial hyperplasia (FEH) or Heck disease is a rare skin disease caused by human papilloma viruses (HPV). The case of a 9-year old boy is presented to demonstrate the successful treatment of massive FEH with 5% imiquimod cream. Initially, the patient had noticed several separate papules, which spread and developed into multiple peri- and intraoral papillomatous nodules. The lesions were treated with carbon dioxide laser destruction. However, multiple, skin-coloured papillomatous nodules were found on the tongue, buccal mucosa and lips 1.5 years later. Treatment with imiquimod was initiated, because the patient suffered tremendously from the disease. 5% imiquimod cream was applied 3 times per week. Regression of lesions was obvious after 1 month of treatment. Complete clearance was achieved after 2 additional months of treatment and no recurrence was detected over a follow-up period of 5 months. Our case points out the clinical value of imiquimod for the non-traumatic and almost painless therapy of HPV-induced skin diseases in children.

Adjuvants, Immunologic↗

PubMed2004

C-KIT expression in primary cutaneous T-cell lymphomas.

BACKGROUND: Mutations of the stem cell factor receptor C-KIT play a major pathogenetic role in the development of different malignant diseases like human mastocytosis, myeloproliferative disorders, gastrointestinal stromal tumors, acute myelogenous leukemia, and sinonasal lymphomas. Furthermore, the expression of C-KIT has been described in Hodgkin's disease and nodal CD30+ anaplastic large cell lymphomas (ALCLs). As it is possible to inhibit C-KIT by innovative kinase inhibitors like STI571, it may be an attractive target for new therapeutical approaches. Therefore, we screened more than 50 different types of cutaneous T-cell lymphomas (TCLs) for the presence of C-KIT. Immunohistochemical stainings were performed on paraffin-embedded tissue sections using a polyclonal rabbit anti-human C-KIT antibody. Naphtol-ASD-chloroacetate esterase (NASDCE)-control stainings were performed on every positive sample to distinguish C-KIT-positive lymphoma cells from C-KIT-positive mast cells. RESULTS: We found weak expression of C-KIT in seven of 18 patients with primary cutaneous CD30+ ALCL, two of eight patients with primary cutaneous pleomorphic TCL, six of 18 patients suffering from mycosis fungoides, and three of five patients with Sezary's syndrome. Generally, only a very small population of the lymphoma cells expressed C-KIT. This finding indicates a difference to the systemic variant of CD30+ ALCL. The potential use of C-KIT targeting new therapeutical approaches is therefore discussed critically, because C-KIT expression is very rare in all investigated types of primary cutaneous lymphoma.

Adult↗

PubMed2003

Imiquimod to treat different cancers of the epidermis.

BACKGROUND: Topical immunomodulatory therapy with imiquimod has been recently used for the treatment of actinic keratoses, intraepithelial carcinoma, and small basal cell carcinoma (BCC) besides the licensed indication of extragenital warts (condyloma). METHODS: We treated several patients with particular epidermal neoplasias such as squamous cell cancer (SCC) and basal cell cancer of sclerodermiform type three times per week for 4 to 12 weeks. RESULTS: We report several novel aspects of the treatment of epidermal cancers with self-applied, nonpainful, immunomodulatory therapy. First, we treated-for the first time-two immunosuppressed renal transplant patients for invasive SCC with imiquimod. Interestingly, systemic immunosuppression did not adversely affect the response to therapy. Second, one patient with the high-risk and aggressive growth pattern of basal cell cancer (sclerodermiform histology) was cured from his disease at a particular location in the face, suggesting sufficient penetration despite scarring. No recurrence was detected in another patient who suffered from 29 BCCs until almost 2-years follow-up. Third, the treatment of actinic keratoses in the face is substantially shorter (in the order of 4 to 6 weeks) as opposed to other skin cancers. Immunomodulatory treatment with imiquimod led to the demarcation of in situ actinic keratosis lesions that could not be identified using the dermatologist's experience, probably because of the existence of exclusive alterations on the molecular level. CONCLUSION: Several novel aspects of immunomodulatory treatment with imiquimod and new indications such as selected cases of sclerodermiform BCC and SCC have been described. The texture of the skin at various different body locations may explain the varying sensitivities to imiquimod when facial skin is compared with skin on the extremities.

Adjuvants, Immunologic↗

PubMed2002

Induction of acute phase response genes in keratinocytes following exposure to oligodeoxynucleotides.

Keratinocytes have the ability to take up oligodeoxynucleotides (ODN) and plasmid DNA probably by receptor-mediated endocytosis. Despite the use of DNA for antisense and gene therapy little is known about the regulation of genes following exposure to nucleic acids. To systematically identify gene regulation in keratinocytes upon exposure to ODN we screened human cytokine DNA arrays containing 383 different genes and found interleukin (IL) 1alpha, IL-1beta, integrin-beta(1), alpha-tubulin, and follistatin highly induced, while most genes were unaffected. The time course and concentration dependence for IL-1alpha and follistatin expression were analyzed by standard northern blot technique. ODN of different length and sequence induced comparable amounts of IL-1alpha and follistatin. Their induction was independent of negative charge and of several proinflammatory compounds such as lipopolysaccharides, IL-1beta, and interferon-gamma but was partly inhibited by activin A. In summary, our study revealed several genes of the acute phase protein family that are induced in a non-sequence-specific manner following the exposure of normal human keratinocytes to ODN. Therefore it is tempting to speculate that upon internalization ODN bind to an intracellular receptor (e.g., Toll-like receptor 9) which mediates signaling.

Acute-Phase Proteins↗

PubMed2002

Reaction of keratinocytes to exogenous DNA.

Keratinocytes have the ability to take up oligonucleotides (ODN) and plasmid DNA probably by receptor-mediated endocytosis or macropinocytosis. Despite the use of DNA for antisense and gene therapy, little is known about the regulation of genes following exposure to nucleic acids. To systematically identify gene regulation in keratinocytes upon exposure to ODN, we screened human cytokine DNA arrays containing 383 different genes and found interleukin-1 alpha (IL-1 alpha), IL-1 beta, integrin beta1, alpha-tubulin and follistatin greatly induced, while most genes were unaffected. The time course and concentration dependence for IL-1 alpha and follistatin was confirmed by the standard Northern blot technique and found to be induced by picomolar or femtomolar concentrations of ODN. ODN of different length and sequence induced comparable amounts of IL-1 alpha and follistatin. Their induction was independent of the negative charge and of several proinflammatory compounds and proteins such as lipopolysaccharides, IL-1 beta or IFN-gamma, but was partly inhibited by activin A. In summary, our study revealed several genes of the acute phase protein family that were induced in a non-sequence-specific manner following the exposure of normal human keratinocytes to ODN. Therefore, it is tempting to speculate that, upon internalization, ODN bind to an intracellular receptor (e.g. Toll-like receptor 9), which mediates signaling.

Activins↗