Gertraud Krähn

Antiapoptotic bcl-2 and bcl-xL in advanced malignant melanoma

Abstract Apoptosis is an important cofactor in the pathogenesis of a plethora of malignancies. However, little is known about modulation of the expression of bcl gene family in melanocytic tumors. To determine the role of bcl-2, bcl-x and bax in melanocytic tumors we investigated the differential expression of these genes via RT-PCR in tissue samples from human ¶benign nevi, primary melanomas and melanoma metastases in comparison with normal skin. Bcl-2 was strongly expressed in 14/16 metastases (87.5%), whereas only 7/13 primary melanomas (53%), 7/15 nevi (46%) and 7/16 normal tissue samples (43%) showed expression of bcl-2 ( P < 0.05). There was a strong indication of a correlation between tumor thickness and bcl-2 expression in nodular malignant melanomas. Expression of bcl-x was found in 16/16 melanoma metastases (100%), 11/13 primary melanomas (84%), 12/15 nevi (80%) and 10/16 normal tissue samples (62%) ( P < 0.05). Bcl-xL expression increased from primary melanoma to melanoma metastases, whereas bcl-xS showed a decreasing expression level during melanoma progression. No differences in bax expression were seen between melanoma metastases, primary melanoma, nevi and normal tissue. Immunohistochemical investigations of another 53 tissue samples showed similar results. Our results strongly indicate that bcl-2 and bcl-xL gene expression increases with progression of malignant melanoma. Bcl-2 and bcl-xL expression could reflect an increased malignant potential caused by an inhibition of apoptosis and growth advantage for metastatic melanoma cells.

Receptor for hyaluronan acid–mediated motility (RHAMM) is a new immunogenic leukemia-associated antigen in acute and chronic myeloid leukemia

OBJECTIVE Identification of leukemia-associated antigens (LAA) eliciting an immune response in patients is a prerequisite for specific immunotherapy of leukemias. To identify new LAA, we used the method of serologic screening of cDNA expression libraries (SEREX). MATERIALS AND METHODS A SEREX library of the cell line K562 was subjected to allogeneic screening with sera from patients with acute myeloid leukemia (AML) or chronic myeloid leukemia (CML) vs sera from healthy volunteers. RESULTS The receptor for hyaluronan acid-mediated motility (RHAMM) involved in cell growth and metastasis was identified as a new LAA. Serologic responses to RHAMM were observed in patients with AML (42%), CML (31%), melanoma (83%), renal cell carcinoma (40%), breast cancer (67%), and ovarian carcinoma (50%), but not in HV or patients with autoimmune diseases. RHAMM mRNA was detectable in peripheral blood mononuclear cells (PBMN) of 60% of newly diagnosed AML patients. Western blotting stained positive for RHAMM protein in 70% of AML patients. mRNA expression of RHAMM also was found in patients with CML (40%), renal cell carcinoma (73%), breast carcinoma (60%), and ovarian carcinoma (50%). In melanoma, RHAMM mRNA expression was detected in metastases (80%) but not in primary tumors. RHAMM is differentially expressed: significant mRNA expression was not found in normal tissues, except from testis, placenta, and thymus, or in PBMN- and CD34-separated cell samples of healthy volunteers. CONCLUSIONS RHAMM is an immunogenic antigen in leukemias and solid tumors and might be a potential target structure for cellular immunotherapies and antibody therapies.

Mycophenolate mofetil: A new therapeutic option in the treatment of blistering autoimmune diseases

BACKGROUND Mycophenolate mofetil (MMF), an ester of mycophenolic acid (MPA), was approved by the Food and Drug Administration in 1995 and is currently primarily indicated for the prophylaxis of rejection in renal transplant patients. The drug seems also to be of value in the treatment of psoriasis and rheumatic arthritis. Recently there have been 6 reported cases of successful treatment of blistering autoimmune diseases with MMF in combination with high dose prednisone therapy. OBJECTIVE On the basis of these reports we administered this new treatment regimen to several patients with blistering autoimmune diseases. Besides using a combination of MMF and high-dose prednisone we wanted to evaluate whether MMF monotherapy is also effective in the treatment of blistering autoimmune diseases. METHODS We administered MMF to 5 patients who had severe pemphigus vulgaris or bullous pemphigoid. Two patients received MMF in combination with high-dose prednisone therapy and 3 patients received MMF monotherapy. To our knowledge, this is the first report of successful treatment of pemphigus vulgaris and bullous pemphigoid with MMF monotherapy. RESULTS All patients were completely free of symptoms within 8 to 11 weeks of therapy. Patients who had received MMF monotherapy responded as well to treatment as those who received a combination of MMF and high-dose prednisone. CONCLUSION Our experiences strongly suggest that MMF monotherapy may be effective for patients even with severe pemphigus vulgaris and bullous pemphigoid. In addition, MMF monotherapy, at least over the short term, offers the advantage of fewer side effects in comparison to immunosuppressive combination therapy and was well tolerated by our patients.

S-100 protein in peripheral blood : A marker for melanoma metastases. A prospective 2-center study of 570 patients with melanoma

BACKGROUND S-100 protein, commonly used in the immunohistochemical diagnosis of malignant melanoma and melanoma metastases, has recently been introduced as a tumor marker in peripheral blood. OBJECTIVE This prospective, observational, 2-center study evaluates S-100 in peripheral blood of patients with melanoma as a marker for metastasis. METHODS With application of an immunoluminometric assay, S-100 levels in 1396 samples of 570 patients with melanoma and 53 control subjects were measured in a blinded manner. RESULTS The cut-off level for patients with melanoma without medical history of metastases versus patients with newly occurring lymph node, visceral, and/or brain metastases was 0.114 microg/L, with a sensitivity of 94% (95% confidence interval, 86.4%-98.5%) and a specificity of 91% (95% confidence interval, 87.7%-93.6%). False-negative results included patients with unknown primary melanoma and those with amelanotic melanoma metastases. CONCLUSION The data suggest that S-100 in the peripheral blood of patients with melanoma could serve as a marker indicating new melanoma metastases and could help to monitor the course of the disease.

Psoralen plus ultraviolet-A-bath photochemotherapy as an adjunct treatment modality in cutaneous chronic graft versus host disease.

Background: Cutaneous chronic graft versus host disease (GVHD) is a severe complication following allogeneic stem cell (PBSCT) and bone marrow transplantation (BMT). Immunosuppressive therapy consists of prednisone, cyclosporine‐A, azathioprine or mycophenolate mofetil (MMF). Treatment of patients refractory to immunosuppression represents a major problem.

Expression of c-myc and bcl-2 in Primary and Advanced Cutaneous Melanoma

Apoptosis is an important co-factor in the pathogenesis of a plethora of malignancies. Enhanced c-myc activation can result either in proliferation or apoptosis. Coexpression with antiapoptotic bcl-2, which abrogates the apoptotic function of c-myc might lead to an enormous growth advantage of cells. In order to elucidate the role of c-myc and bcl-2 as well as the coexpression of both genes in human melanoma, their expression was studied in four samples of normal skin (SK), 15 surgical margins (SM), 20 benign melanocytic nevi (MN), 20 primary melanomas (MM), and 30 melanoma metastases (MMET) by RT-PCR. These results were compared with immunohistochemistry (IH) in 7 SK, 7 SM, 26 MN, 50 MM, and 34 MMET. Similar results were found with both methods. However, MMET expressed c-myc (PCR 28/30, IH 23/34) as well as bcl-2 (PCR 27/30, IH 24/34) more frequently. Primary melanomas showed a similar expression pattern as SM and nevi. Moreover, in contrast to SK, SM, MN, and MM coexpression of bcl-2 and c-myc was found more frequently in MMET (PCR 25/30, p<0.01, IH 19/34, p<0.01). These results indicate that coexpression of c-myc and bcl-2 appears to be associated with advanced melanoma and contributes to the malignant phenotype.

Ultraviolet exposure and risk of melanoma and basal cell carcinoma in Ulm and Dresden, Germany

There is a perpetuating increase in melanoma and basal cell carcinoma (BCC) incidence in Europe. Few studies are evaluating various risk factors for both tumours.

Quantitation of Herpes simplex DNA in Blood during Aciclovir Therapy with Competitive PCR ELISA

Background: Monitoring viral load in blood has already been introduced into clinical routine for human immunodeficiency virus and hepatitis C virus. Objective: This study was conducted to monitor the decline of herpes simplex (HSV) viral load in the blood of a patient with gingivostomatitis herpetica prior and during aciclovir therapy. Methods: Analysis was done by quantitative PCR ELISA using an internal quantitation standard. Results: Copy numbers were 66/µl blood prior to therapy, 60 during oral medication with valaciclovir, 97 and 72 copies/µl blood during the first 2 days of intravenous aciclovir therapy, followed by a sharp decline to 8 and 9 copies on days 3 and 4. During the following days, HSV was no longer detectable. Conclusion: As this quantitative approach can be easily adjusted to any other PCR, it provides a reliable, easy-to-apply method for monitoring therapy, also during new antiviral clinical trials.

Receptor Tyrosine Kinase and p16/CDKN2 Expression in a Case of Tripe Palms Associated with Non-Small-Cell Lung Cancer

Background: Tripe palms is a descriptive term for a cutaneous paraneoplastic keratoderma. Tripe palms are frequently associated with gastric and pulmonary carcinoma. The pathogenetic mechanism remains unknown. Objective: To determine the influence of receptor tyrosine kinases, which are both expressed in pulmonary carcinomas and in human skin, we performed expression studies on epidermal growth factor receptor (EGFR), HER2, HER3 in a skin sample of tripe palms obtained from a patient with non-small-cell lung cancer with lymph node involvement. Two months after diagnosis, the patient had developed palmoplantar ‘tripe palms’. Additionally, the expression of SRC, c-myc and p16/ CDKN2 were studied. Method: Conventional reverse-transcription polymerase chain reaction was performed on a tissue sample of tripe palms. Results: Weak expression of HER2 and of p16/CDKN2 was found. EGFR, HER3, c-myc and SRC were not expressed. Conclusion: Receptor tyrosine kinases of subclass I, the tyrosine kinase SRC and the oncogene c-myc play no major role in the pathogenesis of this case of tripe palms.

Lymph node dissection in cutaneous melanoma: Surgical and oncological implications

The concept of Sentinel Lymph Node Dissection (SLND) has strongly influenced the surgical approach towards primary melanoma in the last decade. Initiated by the disappointing results of elective lymph node dissection (ELND) in this malignancy, the concept of analyzing the first draining lymph node (Sentinel) of a regional basin was developed as a diagnostic means to avoid unnecessary ELND in case of negative SLNs. According to recent standards detection of the SLN should be performed by a triple approach: injection of 90 nm Technetium and patent blue in the periphery of the primary melanoma, and intraoperative tracing of radioactivity with the aid of a hand-held gamma probe. Histopathological examination of alternating series sections of the whole lymph node appears to be the best analytic approach. Molecular biologic procedures such as tyrosinase RT-PCR are time-consuming to perform and produce contradictory results. SLND for cutaneous melanoma is an interdisciplinary diagnostic approach involving surgery, dermatology, pathology, and nuclear medicine. In spite of a variety of published promising results derived from clinical trials ranging from a few dozens to several hundred included patients the diagnostic and prognostic value of SLND remains to be confirmed by ongoing controlled prospective clinical trials. At this stage, SLND can by no means be considered a therapeutic procedure. These aspects have to be kept in mind when informed consent is obtained from patients as well as in the individual determination of the risk-benefit ratio.