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S Gottschlich

Publications and source records attributed to S Gottschlich.

At least 19 recordsLinked to original sources
PubMed1998

[Re-amplification of differentially expressed mRNA fragments of head-neck cancers without cloning].

BACKGROUND: mRNA expression of healthy and malignant cells can be compared to each other by employing the "differential display" (DD) technique. Most studies describe sequence analysis of differentially expressed fragments after reamplification by a second round of PCR and subsequent molecular cloning to gain a sufficient amount of DNA for sequencing. The aim of this study was to show whether a sufficient amount of differentially expressed mRNA of squamous cell carcinoma cells of the head and neck region can be generated by PCR alone without cloning steps. MATERIAL AND METHODS: mRNA isolated from cultivated keratinocytes and squamous cell carcinoma cells was reverse transcribed into cDNA which was amplified with PCR. Differentially expressed fragments detected after gel electrophoresis were isolated from the gel and reamplified in a second PCR. The resulting cDNA amounts of the second PCR were suitable for cloning but not for direct sequencing. A third round of PCR with the undiluted final product of the second PCR as template regularly failed. Dilutions of the second PCR products between 1:10 and 1:10(10) were prepared. The third round of PCR was carried out with these various template concentrations. RESULTS: A sufficient amount of differentially expressed fragments for sequencing procedures resulted when dilutions of the second PCR products ranging from 1:10(2) to 1:10(7) were used as templates in the third round of PCR. CONCLUSION: Modifications of PCR parameters provide high DNA copy numbers of differentially expressed mRNA fragments from squamous cell carcinoma cells of the upper aerodigestive tract in amounts that are needed for sequence analysis. This may make it possible to avoid labor-intensive cloning procedures requiring high safety standards.

Base Sequence↗
PubMed1998

Ultrasound-guided interstitial Nd: YAG laser treatment of voluminous hemangiomas and vascular malformations in 92 patients.

In many cases voluminous vascular anomalies of the head and neck region are still treated with conventional surgery, although neodymium:yttrium-aluminum-garnet (Nd:YAG) laser therapy offers a valuable treatment alternative. Ninety-two patients with voluminous hemangiomas and vascular malformations were treated with interstitial Nd:YAG laser therapy (power density, 1300 to 3300 W/cm2), partly complemented by a noncontact-mode Nd:YAG laser light application (energy density, 1000 to 2500 J/cm2). The vascular tumors had a diameter of more than 3 cm in at least two dimensions. Treatment was carried out under ultrasound and manual control. Nearly 60% of the patients (n = 55) showed a complete clinical regression. Thirty-three patients (35.8%) had a partial regression and were satisfied with the treatment outcome. Four patients were treated unsuccessfully with the laser, and three of them subsequently underwent conventional surgery. Only nine of the 92 patients (9.8%) showed cosmetic or functional impairments. The results of this first consecutive series study with a retrospective clinical evaluation of the interstitial Nd:YAG laser therapy of voluminous hemangiomas and vascular malformations in a large patient group demonstrate a high effectiveness of this novel therapy modality.

Adolescent↗
PubMed1998

Differentially expressed genes in head and neck cancer.

Carcinogenesis is considered a multistep process. To further elucidate involved genetic changes, the differential display method was applied to compare gene expression of head and neck carcinoma cells and normal keratinocytes from the upper aerodigestive tract. Total RNA was extracted from cultured squamous carcinoma cells and keratinocytes. mRNA was reverse transcribed into cDNA, amplified by PCR, and separated on a gel. Currently three DNA transcripts were identified with a length of 191 to 336 base pairs (bp) that were either expressed only by the keratinocytes or by the malignant cells. Differentially expressed DNA fragments of the carcinoma cells and the keratinocytes were cloned and sequenced. A gene bank database search identified one fragment expressed by the carcinoma cells as an unknown gene, another one found in the keratinocytes as probably a part of the human cell attachment domain, and the third one with homology to the mRNA of the human epidermal growth factor receptor (EGFR). Northern blot analysis confirmed the differential expression in the malignant cells or the keratinocytes. Differential display seems to confirm the well-known overexpression and up-regulation of the EGFR, the differential expression of the cell attachment domain may play a role as a cofactor in carcinogenesis of head and neck cancer, and the third unknown fragment is still under investigation to elucidate the role in carcinogenesis.

Base Sequence↗
PubMed1997

Microendoscopic treatment of the hypopharyngeal diverticulum with the CO2 laser.

BACKGROUND AND OBJECTIVE: The hypopharyngeal (Zenker's) diverticulum is a herniation of mucosa and submucosa on the posterior wall of the pharynx. The only treatment is surgical. STUDY DESIGN/MATERIAL AND METHODS: Between 1976 and 1993, 109 patients with a hypopharyngeal diverticulum were operated on at the Department of Otorhinolaryngology, Head and Neck Surgery, University of Kiel, either transcutaneously combined with a cricopharyngeal myotomy (n = 76), or microendoscopically (n = 37) using the CO2 laser. Results and complications of both techniques were evaluated and compared. RESULTS: With both surgical procedures, > 90% of the patients were treated successfully. The rate of postoperative complications was generally low. In comparison to the microendoscopic procedure, serious complications were found to be more frequent in patients treated with the conventional transcutaneous diverticulectomy. CONCLUSION: The laser surgical tissue bridge dissection is a less invasive, quick, relatively safe, and effective procedure requiring only short hospitalisation. Therefore, the laser surgical tissue bridge dissection can be considered as the method of choice for the treatment of the hypopharyngeal diverticulum.

Adult↗
PubMed1997

p53 serum antibodies as prognostic indicator in head and neck cancer.

p53 antibodies are a new serological parameter of unknown potential in patients with malignancies. Their occurrence has been described in various types of cancer patients. The mechanism underlying the immunization process is still unclear. We investigated the incidence of p53 serum antibodies in 143 head and neck cancer patients with an enzyme-linked immunosorbent assay. The posttherapy course of two matched study groups (n = 38 each), one p53-antibody-seropositive and one p53-antibody-seronegative, was followed up for 24 months. Thirty-nine head and neck cancer patients (27.3%) were seropositive for p53 antibodies. During the follow-up, the p53-antibody-seropositive patients accounted for more local tumor recurrences (n = 12 versus n = 8) and more tumor-related deaths (n = 11 versus n = 5) than did seronegative patients, and second primary tumors (n = 9 versus n = 0) occurred exclusively in seropositive patients. In total, therapy failures (recurrences, tumor-related deaths, second primaries) were observed in 17/38 cases (44.7%) in the p53-antibody-seropositive group and in 8/38 cases (21.1%) in the p53-antibody-seronegative group. These results, after a follow-up of 2 years, seem to indicate a prognostic value of p53 serum antibodies for therapy failure in patients with head and neck cancer.

Adult↗
PubMed1997

[Reproducibility of nonradioactive DDRT-PCR method for detection of gene expression in squamous epithelial carcinoma cells of the upper aerodigestive tract].

BACKGROUND: The analysis of the gene spectrum in tumor and normal cells may provide information about genes involved in the differentiation or in the genesis of tumors. Differential Display Reverse Transcriptase Polymerase Chain Reaction (DDRT-PCR) is an innovative method that enables quick analysis of almost all mRNA molecules expressed in the cells. METHODS: In the trials, the mRNAs of keratinocytes and tumor cells were amplified by a number of oligonucleotide pairs after reverse transcription and resolved on polyacrylamide gel. A modified protocol for the amplification of cDNA probes was devised for detecting PCR products with silver nitrate. RESULTS: After reverse transcription of mRNAs, all cDNA samples were successfully amplified using the protocol devised for the silver nitrate DDRT-PCR, and the differentially expressed fragments were reproducibly demonstrated. CONCLUSIONS: The high reproducibility and feasibility of silver nitrate DDRT-PCR expand the alternatives for analyzing gene expression and detecting selectively expressed genes in different kinds of cells.

Carcinoma, Squamous Cell↗
PubMed1997

[Detection of differentially expressed genes in head-neck carcinomas].

BACKGROUND: Carcinogenesis is generally considered a multistage process based on many alterations of the genetic substance. These alterations lead to many qualitative and quantitative changes in gene expression with subsequent malignant transformation of the cell. Only a few of these genetic alterations are identified yet. METHODS: The differential display reverse transcriptase polymerase chain reaction was employed to detect differentially expressed genes in head and neck cancer. The mRNA expression of cultivated keratinocytes of the upper aerodigestive tract was compared to the one of cultivated squamous cell carcinoma cells of the larynx, hypopharynx, and floor of the mouth. RESULTS: A total of 116 differentially expressed gene fragments were identified. They were either solely expressed by the malignant cells or the keratinocytes or in just one carcinoma cell entity. Forty-three of the 116 DNA fragments were sequenced successfully. In four cases the specific differential expression was confirmed by Northern blot hybridisation in comparison to keratinocytes, normal mucosa, and 3 benign tumors from the head and neck region. A gene bank search revealed in three cases a homology of less than 20% to already known human, animal, bacterial or viral gene sequences and in one case a homology of 98% with a human gene sequence. CONCLUSIONS: The detected for squamous cell carcinoma of the head and neck specific genes or gene fragments are the basis for further investigations to better understand carcinogenesis.

Carcinoma, Squamous Cell↗
PubMed1997

[Detection of serum soluble fragments of cytokeratins 8 and 18 in patients with squamous epithelial carcinomas of the upper aerodigestive tract].

BACKGROUND: During the development of squamous cell carcinomas of the head and neck (SCCHN), cytokeratin (CK) 18 and 19, which are typical for simple epithelia, show an elevated expression in tumor tissues. CK 8 was found to be overexpressed in cell lines of SCCHN. Epithelial tumors like normal epithelia express characteristic "pairs" of CK. The smallest of these pairs comprises CK 8 and 18. Therefore, the aim of this study was to serologically detect fragments of CK 8 and 18 (cyfra 8/18) in SCCHN patients. METHODS: Sera of 151 patients with SCCHN were tested for cyfra 8/18 (cyfra 8/18 ELISA medac, Hamburg) before treatment. Thirty sera of healthy volunteers and 43 sera of patients with benign diseases of the head and neck region served as control and reference group, respectively. Thirteen patients were followed-up clinically and serologically after surgery. The serum cyfra 8/18 concentrations of those 13 patients were compared to their clinical run. RESULTS: The cut-off value for cyfra 8/18 was determined with a 95% specificity of the reference group and was fixed at 1.1 ng/ml. The sensitivity was 7%. No correlation was found between cyfra 8/18 and clinical parameters like tumor stage, grading, and tumor location. Cyfra 8/18 concentrations could be correlated to the clinical run of 5 of 13 followed-up patients. CONCLUSIONS: Because of its low sensitivity, the serological detection of cyfra 8/18 must not be seen as a sufficient tumor marker for SCCHN. Its clinical applicability for regular post-surgical controls seems to be restricted and appears inferior to the clinical usefulness of cyfra 21-1.

Biomarkers, Tumor↗
PubMed1997

Expression of a novel mRNA in human head and neck squamous cell carcinoma cells.

AIMS: The differential display reverse transcription polymerase chain reaction (DDRT-PCR) technique was used to search for differences between the mRNA expression profiles of squamous cell carcinoma (SCC) cell lines established from head and neck tumours and normal keratinocytes from the mucosa of the upper aerodigestive tract. METHODS: Total RNA prepared from both cell types was reverse transcribed into cDNA then amplified in a PCR mixture. To compare the electrophoretic patterns, mRNAs were amplified by nested PCR using specific oligonucleotides. Additionally, using labelled cDNA probes, northern hybridisation was carried out on three cancer cell lines of different origin, a biopsy from a parotid gland pleomorphic adenoma, healthy mucosa, and keratinocytes. RESULTS: Comparison of the separated bands revealed a fragment with a differential expression pattern in the SCC cells. This cloned sequence of a 336 base pair mRNA fragment exhibited no significant homology with known transcripts. Additionally, after amplification and sequencing of the 3' end of the fragment no homology with a known human gene sequence was found. However, low homology with a genomic sequence of a nematode was found. Northern hybridisation confirmed the selective expression of this fragment in SCC cells versus the cancer cell lines of different origin, the biopsy of the pleomorphic adenoma, keratinocytes, and healthy mucosa. CONCLUSIONS: This is the first differentially expressed human genome transcript of squamous cell carcinoma of the head and neck identified by DDRT-PCR. It may prove useful, in the future, to characterise this tumour type.

Base Sequence↗
PubMed1997

Optimized differential display and reamplification parameters for silver staining.

Differential display (DD) is a powerful instrument to detect differences in gene expression of malignant and normal cells. An optimized silver staining protocol was used to compare mRNA expression of keratinocytes and squamous cell carcinoma cells of the head and neck. Optimal concentration for upstream and downstream primer was 0.2 microM. Best primer concentrations for reamplification were between 40 and 60 pM. With this optimized protocol nearly 50 differentially expressed transcripts have been identified and differential display can be applied safer, easier, and faster, than by radioactive labeling.

Carcinoma, Squamous Cell↗
PubMed1997

Time-resolved fluorescence spectroscopy of a hematoporphyrin derivative used for photodynamic therapy of cancer.

Photodynamic therapy (PDT) is a treatment modality for malignancies that, uses the accumulation of a photosensitizer in tumor tissue and a subsequent laser light irradiation to selectively destroy tumor cells. Usually PDT is carried out with a hematoporphyrin derivative (HPD) as photosensitizer. Fluorescence characteristics of the HPD Photosan-3 were determined at different concentrations with time-resolved fluorescence spectroscopy. Photosan-3 showed a concentration dependent fluorescence with one fluorescence decay time below a concentration of 10 micrograms/ml, two or three decay times at 50 and 100 micrograms/ml Photosan-3 respectively. These findings confirm results of former studies on other HPD that aggregates and dimers are probably more responsible for the photodynamic effect than monomers.

Fluorescence↗
PubMed1996

[Antibody formation to cellular p53 protein in patients with squamous cell carcinomas of the upper respiratory and digestive system].

BACKGROUND: The mutated form of the nuclear tumor suppressor protein p53 plays an important role as oncogene in the malignant transformation of cells. A new serologic parameter are antibodies against the p53 protein, that are found in many carcinoma entities and localizations and may have a prognostic relevance. Antibodies against p53 in the serum of patients with squamous cell carcinoma of the head and neck (SCCHN) have not yet been described. METHODS: A set of 117 sera from patients with SCCHN were screened for serum antibodies against p53 with ELISA (Dianova, Hamburg). The serum of 41 healthy blood donors served as controls. Tumor tissue of 45 patients was examined with ELISA for p53 protein accumulation. RESULTS: In 23 patients (19.7%) with SCCHN p53 antibodies were demonstrated. The control sera were all negative for p53 antibodies. No correlation was found between the presence of p53 antibodies and tumorstage, tumor grading, age or sex of the patient or tumorlocalization. Thirteen of the 15 tumor samples from p53 antibody positive patients showed detectable levels of p53 protein. CONCLUSIONS: The frequency of p53 antibodies in patients with SCCHN is comparable with the occurrence of these antibodies in other malignancies. An accumulation of p53 in the tumor tissue seems to be necessary to initiate the antibody production. p53 antibodies seem to be an indicator for malignancy in SCCHN and may be of potential diagnostic and prognostic value.

Adult↗
PubMed1996

[Immune response to p53 protein in patients with squamous epithelial carcinoma of the upper aerodigestive tract is independent of p53 point mutation].

OBJECTIVE: Mutations of the p53 gene are the most prevalent genomic changes in human malignancies. The detection of these mutations is usually carried out by gene sequencing or with immunohistochemical methods. A new approach is to search for p53 antibodies in serum of cancer patients. The cause for the production of antibodies against p53 is unclear. The aim of this study was to show the correlation between p53 pointmutations and p53 antibodies in patients with squamous cell carcinoma of the head and neck (SCCHN). METHODS: A semiquantitative ELISA was employed to screen the serum of 117 patients with SCCHN for p53 antibodies. Sixty-one tumor samples were evaluated with SSCP-analysis for point mutations in exons 4 to 9. RESULTS: Twenty-three (19.7%) of the cancer patients had antibodies to p53. There was no significant difference in the frequency of p53 point mutations in exon 4 to 9 between the whole cancer patient group and the p53 antibody positive group. CONCLUSIONS: The accumulation of p53 in the tumor cell is one hypothesis as to how p53 becomes immunogenic. This leads to a decrease in tolerance after a certain amount of time. In contrast to this it is assumed that after a p53 point mutation, important protein determinants are changed and p53 becomes antigenic. The results of this study indicate that p53 point mutations in SCCHN seem to have no influence on the development of p53 antibodies. Therefore this study supports the theory that the loss of tolerance and subsequently the antibody production is induced by an accumulation of p53. The type of p53 point mutations on exon 4-9 seems to have no influence that p53 gains immunogenic potential in SCCHN:

Antibodies, Neoplasm↗
PubMed1996

[Incidence of point mutations in Ki-ras codon 12 and 13 in squamous epithelial carcinomas of the head-neck region].

BACKGROUND: Point mutations of ras genes are one of the most frequent genetic alterations in human malignancies with up to over 95% in certain tumors. Some studies have presumed a low incidence of point mutations in Ki-ras gene codons 12 and 13 in squamous cell carcinoma of the head and neck (SCCHN). The objective of this study was to gain more information about the significance of point mutations in Ki-ras codons 12 and 13 by investigation of a high number of cases. METHODS: By employing the polymerase chain reaction with specific primers, 63 fresh tumor biopsies were investigated by the nonradioisotopic single-strand conformation polymorphism (SSCP) analysis. To cooperate the efficiency and to characterize the nature of the point mutations, direct fluorescence-labeled DNA sequencing was performed in two cases. RESULTS: Five out of the 63 (7.9%) SCCHN samples exhibited point mutations in codons 12 and 13 by SSCP analysis. In two out of these mutated cases, a G to T transversion in codon 12.2 of the Ki-ras gene was detected. The analysis of the patient's clinical parameters as well as the histopathological grading and tumor staging revealed no correlation with the Ki-ras point mutation. CONCLUSIONS: Ki-ras point mutations in codons 12 and 13 are a rare event in SCCHN. These data give additional evidence that these genetic alterations do not play a major role in the development of malignancies of the upper aerodigestive tract.

Aged↗
PubMed1996

[Monoclonal antibodies against squamous epithelial carcinomas of the upper aerodigestive tract].

BACKGROUND: Squamous cell carcinoma is the most common cancer of the head and neck. The application of monoclonal hybridoma technology to the identification and characterization of molecules preferentially expressed in carcinoma cells may provide potentially important diagnostic and therapeutic tools. METHODS: After immunization of mice with viable squamous cell carcinoma cells derived from human tumors of the upper aerodigestive tract hybridomas were selectively grown for production of monoclonal antibodies. Monoclonal antibodies produced by 690 hybridoma clones were tested on immunoreactions with frozen sections of human squamous cell carcinoma and reactive tonsils. RESULTS: Immunohistochemical trials showed that monoclonal antibodies produced by hybridoma clone K-640 are strongly accumulated at the plasma membrane whereas no immunoreaction in squamous epithelium of the tonsil could be detected. By means of ELISA it could be shown that these antibodies belong to the class of IgM. Immunoblotting revealed that the antibodies recognize antigenes with approximate molecular weights of 52 and 54 kD. CONCLUSIONS: The experiments suggest that the hybridoma clone K-640 produces antibodies which bind to the plasmamembrane of the tumor cells. Further recloning steps of this hybridoma clone could possibly enhance the specificity of these antibodies for squamous cell carcinoma.

Animals↗
PubMed1995

[Serum soluble interleukin 2 receptor in patients with squamous epithelial carcinomas of the upper aerodigestive tract].

BACKGROUND: Several investigations showed increased levels of the soluble interleukin-2 receptor (sIL-2 R) in chronic and malignant diseases. A correlation between elevated sIL-2 R levels and disease activity or tumor size was observed in some patients. At present, there are no studies of sIL-2 R serum levels in patients with squamous cell carcinomas of the upper aerodigestive tract. METHODS: SIL-2 R levels were measured in sera of 86 patients with squamous cell carcinoma of the head and neck and of 25 healthy controls with a sandwich ELISA. RESULTS: Significantly elevated serum levels of sIL-2 R were detected in 49 out of 86 patients (56.9%) with squamous cell carcinoma of the head and neck. The mean serum level in the healthy controls was 437 U/ml compared to 895 U/ml in carcinoma patients. A correlation was found between tumor size, number of metastases and the sIL-2 R level. There was no correlation with histological type or tumor localization. DISCUSSION: The physiological role of sIL-2 R is still unknown. Elevated levels of sIL-2 could be a sign of activation of the immune system. But they also might be involved in causing the disease. The sIL-2 R serum levels in patients with squamous cell carcinoma of the head and neck may serve as an unspecific indicator for tumor size and dissemination. CONCLUSION: Posttherapeutic titer controls could be of prognostic value. Additionally, sIL-2 R may help to select appropriate patients for an immunotherapy with recombinant IL-2.

Adult↗
PubMed1995

[Establishment and characterization of 2 cell lines of squamous epithelial carcinoma of the mouth floor and tongue].

OBJECTIVE: The cultivation of squamous cell carcinoma cells of the upper aerodigestive tract is more difficult compared to other malignancies because of microbial contamination. The establishment of new squamous cell carcinoma cell lines is absolutely necessary to further characterize this tumor entity. METHODS: Two squamous cell carcinoma cell lines of the floor of the mouth and the tongue were established from tumor biopsies. They were examined by light and electron microscopy. Furthermore immunocytochemical and DNA cytofluorometric studies were performed. The growth features were tested in a tumor-stem cell assay and through transplantation in thymusless nude mice. RESULTS: The epithelial character of the cells was determined morphologically, immunocytochemically, and immunologically. Both cell lines shaved an aneuploid DNA Index of 1.92 for the tongue carcinoma cell line (HCTK-1) and 1.77 for the floor of the mouth cell line (HCFMK-1). The plating efficiency was 0.008 and 0.01%. Cell differentiation in the original tumor and the nude mice tumor was identical. HCTK-1 is in the 25th passage and HCFMK-1 in the 42nd. CONCLUSIONS: The two new squamous cell carcinoma cell lines HCFMK-1 and HCTK-1 may serve as a basis for various in vitro investigations and may help to further characterize squamous cell carcinomas of the upper aerodigestive tract.

Aged↗