Experimentelle 5-Aminolävulinsäure – induzierte photodynamische Therapie (ALA-PDT) oraler Karzinome

AIMS

Of our own patients suffering from oral squamous cell carcinoma (OSCC), 96% possessed a 5-aminolevulinic acid (ALA)-induced tumor fluorescence. Consequently, the ALA-induced fluorescence of OSCC is suggested as an ideal tool for selective photodynamic therapy (PDT). The aim of the study was to demonstrate selective tumor damage and to analyze the cell death mode (apoptosis vs. necrosis) of OSCC cells in cell culture and in solid, deeply invasive xenotransplants in immunodeficient nude mice using intratumoral laser illumination.

MATERIAL AND METHODS

For ALA-PDT, laser light (635 nm, 0.75 W, 10 min, cooled application system) was used intratumorally as well as in cell culture. The therapeutic response was controlled by histology and immunohistochemistry (Ki-67 index). The apoptosis was evaluated by the TUNEL method and in vitro by flow cytometry. Mutations in the apoptosis-controlling p53 gene were investigated by direct genomic sequencing.

RESULTS AND CONCLUSIONS

1. Although all OSCC exhibited an ALA-induced fluorescence in vivo, the evaluation of the cell lines showed differences in intensity of the ALA-induced fluorescence. This points to a different sensitivity of OSCC for ALA-PDT. 2. The use of a cooled laser light application system allowed intratumoral radiation and treatment of deeply invasive OSCC regions. 3. The cytotoxic effect of ALA-PDT in OSCC is evidenced by a diminution of proliferative activity and necrosis but not by apoptosis. 4. Functional mutations within the p53 gene were considered a possible reason for the absence of apoptosis induction by ALA-PDT.

Telomerase activity and telomere length in different areas of renal cell carcinoma

Telomerase activity and telomere length were analyzed in a total of 59 surgically removed primary renal cell carcinoma (RCC). The study includes tissue from the centre of the tumor, several different peripheral tumor areas, metastases and secondary tumors. None of the normal renal cortex tissues used as control exhibited telomerase activity. In contrast, telomerase activity was detected in 55 out df 59 (=93%) tested primary RCC. There was no case with intratumoral heterogeneity concerning the telomerase activity status. All metastases and secondary tumors were telomerase-positive. In the four telomerase deficient tumors all measured telomeric repeat fragments were shortened in comparison to the normal tissue. As these patients exhibit no metastases or secondary tumors a less malignant variant of RCC is supposed. There was no correlation between telomerase activity and specific histopathological subtypes of RCC or specific chromosomal aberrations. As telomerase activity is not associated with advanced stages of tumors it may be an important early event in the development of RCC. Thus, telomerase activity may be a prevalent marker for early and late stages of all subtypes of RCC.

Unusual manifestation of a multiple myeloma in the hyoid bone

The most common manifestation of plasma cell neoplasms is multiple myeloma. Solitary and localized tumours in the form of solitary plasmacytoma of the bone or extramedullary plasmacytoma are rare. In the late stages of multiple myeloma, bulky bone tumour infiltrates may be found which may be the primary clinical manifestation of the previously unknown malignancy. We report a case of a hyoid bone tumour with extramedullary plasma cell infiltrates in the oropharynx in multiple myeloma.

B domain containing Tenascin-C: a new urine marker for surveillance of patients with urothelial carcinoma of the urinary bladder?

BACKGROUND

ECM remodelling during tumorigenesis entails the re-occurrence of different Tn-C(L) splicing variants. In patients with urothelial carcinoma of the urinary bladder (UBC), B and C domain containing Tenascin-C (B(+) and C(+) Tn-C) urine levels were shown to be increased in case of muscle invasiveness. Thus, the present study was aimed at examining the ability of B(+) and C(+) Tn-C as potential urinary surveillance markers of UBC patients.

METHODS

Urine levels of B(+) and C(+) Tn-C were determined by ELISA in 35 UBC patients during a 2 year follow-up period after therapy and related to clinical diagnosis and histological stage in 4 defined groups representing typical courses of disease.

RESULTS

B(+) Tn-C levels showed significant differences between cases of tumour progression or regression. The urine levels of B(+) Tn-C could be used to discriminate between cases without tumour recurrence and such with tumour existence (cut-off value: 0.8 ng/ml) or between non-muscle invasive and muscle invasive tumour growth (cut-off value: 3.5 ng/ml).

CONCLUSIONS

Progression of UBC with time is accompanied by significant changes in urinary levels of B(+) Tn-C. Urinary B(+) Tn-C can therefore be suggested as a valuable urine surveillance marker in UBC follow-up care.

Extra cellular matrix remodelling after heterotopic rat heart transplantation: gene expression profiling and involvement of ED-A+ fibronectin, alpha-smooth muscle actin and B+ tenascin-C in chronic cardiac allograft rejection

Chronic cardiac rejection is represented by cardiac allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) known to cause severe complications. These processes are accompanied by remarkable changes in the cardiac extra cellular matrix (cECM). The aim of our study was to analyse the cECM remodelling in chronic rejection and to elucidate a potential role of ED-A domain containing fibronectin (ED-A(+) Fn), alpha smooth muscle actin (ASMA) and B domain containing tenascin-C (B(+) Tn-C). A model of chronic rejection after heterotopic rat heart transplantation was used. Allografts, recipient and control hearts were subjected to histological assessment of rejection grade, to real-time PCR based analysis of 84 genes of ECM and adhesion molecules and to immunofluorescence labelling procedures, including ED-A(+) Fn, ASMA and B(+) Tn-C antibodies. Histological analysis revealed different grades of chronic rejection. By gene expression analysis, a relevant up-regulation of the majority of ECM genes in association with chronic rejection could be shown. For 8 genes, there was a relevant up-regulation in allografts as well as in the corresponding recipient hearts. Association of ASMA positive cells with the grade of chronic rejection could be proven. In CAV and also in CIF there were extensive co-depositions of ED-A(+) Fn, ASMA and B(+) Tn-C. In conclusion, chronic cardiac allograft rejection is associated with a cECM remodelling. ASMA protein deposition in CAV, and CIF is a valuable marker to detect chronic rejection. Interactions of VSMCs and Fibro-/Myofibroblasts with ED-A(+) Fn and B(+) Tn-C might functionally contribute to the development of chronic cardiac rejection.

Epidermal growth factor receptor kinase domain mutations are rare in salivary gland carcinomas

Activating mutations within the epidermal growth factor (EGFR) tyrosine kinase domain identify non-small cell lung cancer patients with improved clinical response to tyrosine kinase inhibitor therapy. Recently, we identified two EGFR mutations in a cohort of 25 salivary gland carcinomas (SGCs) by screening the tumour samples for the both most common hotspot mutations in exons 19 and 21 by allele-specific PCR. Here, we present a comprehensive sequencing analysis of the entire critical EGFR tyrosine kinase domain in 65 SGC of the main histopathological types. We found EGFR mutations in the tyrosine kinase domain to be a rare event in SGCs. No additional mutations other than the two known exon 19 deletions (c.2235_2249del15) in a mucoepidermoid carcinoma and an adenoid cystic carcinoma have been detected. Other putative predictive markers for EGFR-targeted therapy in SGCs might be relevant and should be investigated.

Consequences of one-lung flooding: a histological and immunological investigation

BACKGROUND

Videothoracoscopic lung sonography after partial fluid instillation could be a new method for endoscopic detection of lung lesions. Histopathological consequences of unilateral diagnostic or therapeutic lung flooding under bronchoalveolar lavage has yet to be defined. The aim of the study was to investigate histological and immunohistological alterations induced by one-lung flooding (OLF).

METHODS

13 female pigs were subjected to OLF (15 ml isotonic electrolyte solution per kg for 60 minutes), and lung tissue was collected 30 minutes, 2 hours, 24 hours, 48 hours, 6 days, 8 days, and 10 weeks after flooding. Histological examinations and immunohistochemical labeling for surfactant protein A (SP-A) were performed. Cellular proliferation was measured by Ki67 immunohistochemical labeling. Apoptosis was detected through enzymatic in-situ labeling of apoptosis-induced DNA strand breaks by means of the TUNEL (TdT-mediated dUTP nick end labeling) method.

RESULTS

Histological analyses revealed the presence of inflammatory cell infiltrates in the interstitium at 24 hours after OLF. However, no destruction of the alveolar wall and no pulmonary oedema were observed. In addition, OLF was not associated with any decrease in surfactant protein A immunoreactivity. Two hours after OLF, the number of apoptotic cells was increased (OLF: 7% vs.

CONTROL

0.6%, p < 0.05), but cellular proliferation was unchanged. Conversely, at 48 h after OLF, the number of apoptotic cells had returned to control levels, but cellular proliferation had increased (OLF: 5% vs.

CONTROL

1.1%, p < 0.05). Cellular proliferation returned to baseline levels eight days after OLF.

CONCLUSIONS

These data demonstrate that OLF is not associated with destruction of the alveolar texture, atelectasis-provoking surfactant loss, or any irreversible damage to the pulmonary parenchyma. Lung flooding for the purpose of videothoracoscopic lung sonography is safe and justifiable. But repeated lung flooding under bronchoalveolar lavage involving the same lung area within 1 week is not to be recommended.

mRNA expression and protein distribution of fibronectin splice variants and high-molecular weight tenascin-C in different phases of human fracture healing

Fracture healing is a reparative physiological process, which proceeds in stages, each characterized by the predominant tissue in the fracture gap. The tissue matrix is continuously reorganized by cell migration, proliferation, and differentiation. Adhesive proteins such as fibronectin and tenascin transmit information between matrix and cells. As a result of alternative splicing of pre-RNA, EDA + fibronectin, EDB + fibronectin, and high-molecular weight (hm) tenascin-C are generated. By definition, EDB + fibronectin is an oncofetal protein because it is extremely rare in normal adult tissue and plasma, whereas it is expressed in fetal and tumor tissues and during wound healing. In this study, we for the first time describe EDA + fibronectin, EDB + fibronectin, and hm tenascin-C expression in human fracture gap tissue during various stages of differentiation. We demonstrate mRNA expression of all three splice variants in the initial fibrin matrix with upregulation in the enchondral ossification/osteoid and woven bone stages. Of all variants, EDA + fibronectin mRNA has the highest concentration in all stages. For the analysis, we used LightCycler-based relative mRNA quantification and immunohistochemistry. Our data demonstrate that EDA + fibronectin and hm tenascin-C show a diffuse distribution pattern in fracture gap connective tissue, while EDB + fibronectin is focally concentrated in osteoblastic cells at the margins of woven bone. EDA + fibronectin and hm tenascin represent markers for active granulation processes, whereas EDB + fibronectin is specific for cells forming the enchondral and osteoid matrix. The possibility of stimulating fracture healing by EDB + fibronectin-cytokine complexes should be tested in further investigations.

Laminin-5 immunocytochemistry: a new tool for identifying dysplastic cells in oral brush biopsies

BACKGROUND

The brush biopsy technique is not only a seminal technique but also a critically discussed method for detection of oral pre-cancerous stages and manifest carcinomas. The gamma2 chain of laminin-5 and its proteolytic fragments comprise an invasion factor for many carcinomas.

OBJECTIVES

The aim of this study was to determine whether the immunocytochemical presentation of the laminin gamma2 chain identifies pre-invasive or invasive squamous cells in brush biopsies.

METHODS

The value-based identification of atypical epithelia was analysed in 93 consecutive brush biopsies with histopathological diagnoses: standardized haematoxylin and eosin staining; standardized immunocytochemistry: monoclonal antibodies against laminin gamma2 chain: D4B5, 4G1, detection using ChemMate and Autostainer.

RESULTS

Conventional cytology did not result in any false-positive cases, i.e. atypical cells in normal, inflamed or benignly hyperproliferative mucosa (specificity, 100%), whereas immunocytochemistry revealed one false-positive case (specificity, 98%). In brush biopsies of oral squamous cell carcinomas, the following immunocytochemical patterns were possible: (1) staining of the cytoplasm, (2) banded markings between clumped carcinoma cells and (3) positive hazes surrounding atypical cells. Bacterial colonies appeared as false-positive results. Four of 27 carcinomas and one of three recurrences were not cytologically identified (sensitivity of conventional cytology, 79%). Three of the five carcinomas not identified by cytology were immunocytochemically stained with laminin gamma2 chain antibody (sensitivity of laminin gamma2 chain immunocytochemistry, 93%). The positive predictive value was 100% for conventional cytology and 97% for laminin gamma2 chain immunocytochemistry. The negative predictive value attained was 92% for conventional cytology and 97% for laminin gamma2 chain immunocytochemistry.

CONCLUSIONS

The high sensitivity level observed for method-enhanced brush cytology suggests that this technique be used as an initial diagnostic step.

Urethroplastik mit Gewebematrix

BACKGROUND

The purpose of this study was to examine whether use of small intestinal submucosa in microsurgical urethroplasty in Wistar rats represents an alternative.

METHODS

In 20 Wistar rats microsurgical urethroplasty with small intestinal submucosa was done to repair distal or proximal urethral defects. Four weeks later urethral calibration and urethrography were performed in addition to histological studies.

RESULTS AND CONCLUSIONS

Of the 20 animals, 19 survived the observation period without evidence of fistulas, strictures, stenoses, or necroses. The histological results confirmed an intact tissue layer.

[Oral cytology: historical development, current status, and perspectives]

Oral cytology has aroused new interest caused by introduction of the cytobrush as a sampling device and the use of additional analytical methods. By brushing it is possible to reach deeper layers of the oral mucosa where squamous intraepithelial neoplasia (SIN) begins. The biological potential of the oral epithelial cells obtained can be evaluated by the following additional methods: computer-assisted image analysis (OralCDx), DNA cytometry, immunohistochemistry, monolayer cytology, and molecular biological analysis. All of those methods can increase sensitivity (up to 100%) and specificity (up to 100%) of oral brush biopsy. Nevertheless, there are reports that oral epithelial carcinomas were not identified. No comparative study exists allowing conclusions to be drawn about the value of the single methods. Immunocytochemistry with commercial antibodies against laminin-5 is generally available and methodologically easy. Oral brush biopsy as a non invasive diagnostic method can be useful for the early detection of oral mucosal lesions. Positive findings or progression of the lesion despite negative findings are indications to refer the patient to a specialized clinic where a surgical biopsy should be performed, followed by histopathological analysis. Histopathology remains the gold standard for the definitive diagnosis of oral malignant lesions.

[Clinical and immunohistochemical findings of intra- and extraoral angiosarcomas]

PURPOSE

A clinico-pathologic study of typical symptoms of intra- and extraoral angiosarcomas and clinical course under therapy is presented as well as an analysis of the immunohistochemical differential diagnosis of the tumour specific formed spaces.

PATIENTS AND METHODS

Four male patients aged 63-78 years suffered from angiosarcomas of the maxillary sinus, the bucca (two patients) and the alveolar ridge of the lower jaw.

HISTOPATHOLOGY

For comparative analysis paraffin embedded tissue of the initial biopsies was available. The slides were stained with standardized H&E, PAS and Gömörri. For standardized immunohistochemistry following primary antibodies were applied: monoclonal antibodies to pancytoceratin clones AE1/AE3, alpha-smooth-muscle-actin clone 1A4, CD31 clone JC/70A, factor-VIII-related antigen clone F/86, Fli-1 (polyclonal, Zymed, USA), tenascin-C: BC4 (Prof. L. Zardi), oncofetal glucosylated fibronectin clone FDC6 (ACCR), laminin-5: D4B5. Detection using AP-ChemMate and Autostainer (Dako, Denmark).

RESULTS

While the benign appearance of the lesions resulted primarily in wrong diagnoses the histopathologic examination of the biopsies revealed the characteristic pattern of angiosarcomas. Wide surgical excision, radiotherapy and/or antiangiogenic chemotherapy could not prevent tumour progression and death within two and a half years after primary diagnosis. All angiosarcomas reacted partially positive for factor-VIII-related antigen and CD31. The tumour associated structural defect of vascular lamina with partial loss of pericytes/vascular smooth muscle cells was identified immunohistochemically by alpha-smooth-muscle-actin and for the first time by tenascin-C.

CONCLUSIONS

(1.) The variable presentation and the benign appearance of oral and perioral angiosarcomas may often delay diagnosis. Oral and perioral angiosarcomas show poor prognosis despite of multimodal therapy. (2.) Cytoceratin and laminin-5-positivity as typical epithelial antigens don't exclude angiosarcoma. Factor-VIII-related antigen, CD31 as well as Fli-1 identify angiosarcoma. (3.) alpha-smooth-muscle-actin and the loss of the tenascin-C-matrix indicate immunohistochemically the characteristic sarcomatous defect of differentiation.

High-molecular tenascin-C as an indicator of atypical cells in oral brush biopsies

Tumour-invasion like wound healing is characterised by the formation of an extracellular matrix with a high tenascin-C content. The tenascin-C molecule undergoes alternative splicing. Analysis using antibody BC2 indicates that especially the high-molecular tenascin-C (hm tn-C) variants are typically tumour-associated, while distribution in normal tissue is restrictive. This study investigated whether hm tn-C is a suitable indicator of atypical cells with invasive potential in oral brush biopsies. One hundred fifty nine consecutive oral brush biopsies with histopathological diagnoses were analysed for the identification of atypical cells. A standardised haematoxylin and eosin staining plus standardised immunocytochemistry using the monoclonal anti-hm tn-C antibody was performed. The bound hm tn-C antibodies were detected with the streptavidine/alkaline phosphatase technique in the autostainer. Conventional cytology produced four false-positives when identifying atypical cells in brush biopsies of inflammatory/benign hyperproliferative mucosa (specificity 96%), while 10 in 52 carcinomas and three of eight recurrences were not identified (sensitivity 78%). Ten of these 13 non-identified tumours could be marked when adding the hm tn-C assay (increasing specificity to 99%). Combining the two assays also reduced the false-positive outcomes from four to one (increasing sensitivity to 95%). The positive and negative predictive values were 92 and 88% for conventional cytology vs 98 and 97% for the dual assay. (1) A 95%-sensitivity proves hm tn-C assisted conventional cytology to be a suitable means of identifying atypical cells in oral brush biopsies. (2) The positive (98%) and negative (97%) predictive values obtained approximate hm tn-C assisted conventional cytology to laminin-5 (100/97%).

Zentrales Riesenzellgranulom des Unterkiefers

The synopsis of radiographic examination (uni- or multilocular radiolucency), histologic findings (giant cells throughout a benign fibroblastic matrix), blood chemistry analysis (normal serum parathyroid hormone) and clinical features provides the definitive diagnosis of giant cell granuloma, allowing the clearly defined surgical management of this lesion. The case history of a 48-year-old female patient who presented with a giant cell granuloma in the right mandible is used to illustrate this controversially discussed intra-osseous lesion. The potential therapeutic change from radical operative treatment, including functional maintenance, to conservative procedures is emphasized.

Aktuelle Klassifikation der Präkursorläsionen des oralen Plattenepithelkarzinoms

The WHO classification of oral tumours summarizes the precancerous squamous cell lesions under the term epithelial precursor lesions. For the first time three classification schemas that histologically categorize oral epithelial precursor lesions are used analogously. According to the WHO suggestion of 2005 the traditional schema of grading dysplasia as mild dysplasia, moderate dysplasia, severe dysplasia and carcinoma in situ continues to be used. In addition the concept of intraepithelial neoplasia is introduced as squamous intraepithelial neoplasia I-III. Squamous intraepithelial neoplasia III (SIN III) combines severe dysplasia and carcinoma in situ. The Ljubljana classification of squamous intraepithelial lesions was originally established to grade laryngeal epithelial precancerous lesions. The clear and succinct nomenclature and the simple clinical utility of the Ljubljana classification have also proven to be useful for oral epithelial precursor lesions: squamous cell (simple) hyperplasia; basal/parabasal cell hyperplasia (analogous to mild dysplasia and to SIN I); atypical hyperplasia (analogous to moderate-severe dysplasia and to SIN I-III and is also called risky epithelium); carcinoma in situ (analogous to WHO carcinoma in situ and to SIN III). Atypical hyperplasia (risky epithelium) and carcinoma in situ are defined as lesions requiring either total excision or close clinical monitoring.

Das Urothelkarzinom mit trophoblastischer Differenzierung

Urothelium carcinomas with beta HCG positive markers are a rarity in tumour differentiation. Syncytiotrophoblastic and, in a few cases, cytotrophoblastic giant cells are typical for this carcinoma. Such differentiation has an intensified potential for invasiveness and is accompanied by increased angiogenesis. In the present case, the mixture of trophoblastic cells indicates a common stem cell. In comparison with beta HCG negative transitional cell carcinoma, the prognosis is bad for beta HCG positive carcinoma. For this reason, a radical operation should be taken into consideration as early as possible.

Expression of EDA+ and EDB+ fibronectin splice variants in bone

The extracellular matrix component fibronectin (fn) has fundamental functions in cell attachment, differentiation, proliferation, and migration. Isoforms of cellular fibronectin, named EDA+ fibronectin or embryonal EDB+ fibronectin, are generated by alternative splicing of its mRNA precursors. Little is known about the expression of EDA+ and EDB+ fibronectin splice variants in human bone. The aim of this study was to investigate the expression pattern of fibronectin splice variants in bone cell lines and in different human bone tissue samples (mature bone, early stages of fracture healing, hypotrophic nonunion, osteosarcoma). Analysis was done by immunostaining with recombinant and monoclonal antibodies, qualitative RT-PCR and LightCycler-based real-time quantitative RT-PCR assay. In osteoblast and osteosarcoma cell lines, abundant expression of EDA+ and EDB+ fibronectin was found in immunocytochemistry. High transcription levels of both splice variants mRNA were seen in quantitative RT-PCR in osteosarcoma cell lines. In mature bone, EDA+ and EDB+ were not detectable in immunohistochemistry. Transcription of mRNA in both splice variants was absent in these samples. Early stages of fracture healing and osteosarcoma cell samples exhibited extensive staining for EDA+ and EDB+ fibronectin, and high mRNA levels were found. Both osteosarcoma and bone fracture healing tissue expressed high mRNA levels of the fibronectin splice variants independent of benign or malignant behavior. Low level of EDA+ fibronectin mRNA transcription and focal immunohistochemical staining of EDA+ fibronectin was found in hypotrophic nonunions, whereas EDB+ fibronectin was not detected by immunohistochemistry and qualitative or quantitative PCR. EDA+ fibronectin was found in granulation tissue-forming processes in bone independent from bone-forming activity. EDB+ fibronectin was seen only in high-turnover new osteoid-forming processes like early stages of fracture healing and osteosarcoma and was absent in low-turnover processes like mature bone and hypotrophic nonunion. Both EDA+ and EDB+ fibronectin mark active processes in bone without differentiation between malignant or benign activity. In conclusion, EDA+ and EDB+ fibronectin splice variants are strong markers for active fibrogenetic and osteoid-forming processes in human bones.

Intra- und postoperatives Monitoring von Lappentransplantaten

BACKGROUND

According to Schmelzeisen et al. (1996), the failure rate for microvascular free flaps is 5%. While surface tissue oxygenation can be assessed clinically, if necessary by a puncture, the oxygen supply to deeper areas mostly cannot be checked. We therefore wished to find whether measurement of tissue pO(2) would prove to be an objective and practical technique that could be used for continuous and accurate intra- and postoperative evaluation of flap perfusion.

MATERIAL AND METHODS

A Clark-type microcatheter was used intra- and postoperatively to monitor tissue pO(2) in 5 pedicled pectoralis major flaps and 32 free revascularized flaps (9 jejunal flaps, 5 latissimus dorsi flaps, 6 radial forearm flaps and 12 scapular flaps).

RESULTS

The mean values for tissue pO(2) were significantly lower in pedicle grafts than in free revascularized flaps. Within in each flap group the pO(2) values measured did not vary significantly over an observation period of up to 77.2 h after transplantation.

CONCLUSIONS

Continuous measurement of tissue pO(2) by means of a Clark-type microcatheter combined with clinical examination constitutes a reliable method of monitoring tissue oxygenation in pedicle grafts and free revascularized flaps during the intra- and postoperative phases. Analysis of small and of wide fluctuations in pO(2) values may help in the diagnosis of early arterial and venous obstructions in flaps and may in the future result in new insights into the tissue oxygenation in surgical flaps allowing some alleviation of the problems currently experienced in clinical monitoring.

Re-distribution of tenascin-C in the parotid acinar cells. An early marker of radiation-induced damage of salivary glands?

PURPOSE

In order to investigate the early changes in the expression of tenascin-C, following irradiation and the associated functional impairment of salivary glands.

MATERIALS AND METHODS

Fifteen rabbits were used for the study. Five provided control parotid gland tissue and a further 10 rabbits were scintigraphically examined prior to and 24 h after 15/30 Gy. Glands were studied histologically using HE-staining and tenascin-C antibodies.

RESULTS

Reduction in the salivary ejection fraction (SEF) was observed in all irradiated glands. Simultaneously, a marked re-distribution of tenascin-C expression was noticed. Reactivity detected in the intercalated, secretory ducts and perineurinal regions prior to radiation was noticed intracellularly after 24 h. Furthermore, nerves showed tenascin-C expression in the Schwann cells, but no longer perineurinally. Myofibroblasts were also observed in the stroma.

CONCLUSION

This study proves the ability to predict functional disorders of salivary function as early as 24 h after radiation and provides evidence of the participation of tenascin-C in the pathological process of radiation-induced damage in salivary glands.

Acute effects of tourniquet occlusion and intraluminal shunts in beating heart surgery

OBJECTIVE

MIDCAB and OPCAB revascularization is currently performed with temporary tourniquet occlusion of the coronary artery to achieve a bloodless surgical field. However, a trauma of the vessel wall due to snaring sometimes occurs. The use of temporary intraluminal shunts (TILS) have recently been advocated as an alternative. The aim of this experimental study was to evaluate the acute ultrastructural effects of TILS versus tourniquet occlusion on the coronary vessel wall.

METHODS

Twelve pigs (40+/-3 kg) were investigated. In group A (n=6) the left anterior descending (LAD) artery was temporarily occluded with a tourniquet over 20 min. In group B (n=6) a commercially available silicone TILS (1.5-mm diameter, 12-mm length, AnastaFlo, Research Medical Inc.) was placed in the LAD. After 20 min perfusion the TILS was removed and the insertion was repaired. After 30 min reperfusion all animals were killed. Three LAD territories of each animal were examined histopathologically by scanning electron microscopy (SEM), light microscopy (LM) and transmission electron microscopy (TEM). Areas of occlusion or placement of the TILS olives were investigated.

RESULTS

SEM revealed ultrastructural alterations in both groups. While marked intimal rupture appeared in all animals of group A, only two of the six animals of group B exhibited superficial endothelial abrasions. LM showed differences of intimal thickness in all groups while TEM revealed severe edema of subendothelial tissue in four of six animals in group A.

CONCLUSION

The intimal lesions observed after tourniquet occlusion in our experimental off-pump surgery model confirmed other recent studies. In contrast, utilization of TILS caused only minor damage of the vessel wall. The endothelial abrasions detected in this group may be a consequence of micro-dislocations or insertion maneuvers. Chronic studies are necessary to verify as to whether the mild injury after TILS insertion will result in a reduction or even absence of de-novo stenoses compared with tourniquet occlusion.

Early immunohistochemical and functional markers indicating radiation damage of the parotid gland

In order to evaluate the correlation between functional impairment and changes in the expression pattern of immunohistochemical antibodies in the early phase of radiation-induced dysfunction of salivary glands, eight rabbits were scintigraphically examined prior to and 24 h after irradiation with 15 Gy. The parotid glands were studied using HE-staining, Ki-67, alpha-smooth muscle actin (ASMA) and tenascin-C antibodies at every scintigraphic examination. The results demonstrated a significant alteration in the 99mTc-pertechnetate uptake in all irradiated glands. HE-staining showed no relevant impairment of salivary gland tissue in this early phase. Immunohistochemically, we observed a marked re-distribution of ASMA and tenascin-C as well as a reduction of the proliferating rate of acinar cells. This immunohistochemical change correlated with the functional impairment manifested scintigraphically. This study proves the possibility to assess disorders of salivary gland function with immunohistological antibodies as early as 24 h after irradiation and yields the prerequisites to prove the effects of radioprotective agents on salivary gland tissues.

New Cut-Off Point between T1 and T2 Renal Cell Carcinoma – Necessary for a Better Discriminatory Power of the TNM Classification

PURPOSE

We evaluated the pathological features of tumor size, lymph node and distant metastases, cell type, growth pattern, infiltration pattern, histological grade, local invasion and venous involvement of organ-confined renal carcinomas. The aim of this study was the re-evaluation of the TNM classification and the tumor cut-off point between T1 and T2 for renal cell carcinomas from the 1987 to the 1997 versions.

MATERIALS AND METHODS

(1) Patients with renal cell carcinoma who had been operated between October 1992 and August 2001 were evaluated. 437 of 691 patients showed T1 and T2 tumors. These organ-confined tumors have been divided into five groups: group 1: tumor-size of 20 mm or less (n = 16), group 2: 21-30 mm (n = 79); group 3: 31-40 mm (n = 83; group 4: 41-70 mm (n = 184), and group 5: more than 70 mm in diameter (only T2, n = 75). Follow-up ranged from 0 to 100 months (average 28.63 months). (2) Of 15,347 autopsies performed in Jena between 1985 and 1996, 272 renal cell carcinomas were revealed. In 145 of these 272 cases renal cell carcinomas were limited to the kidney. These 145 tumors were divided accordingly into 5 groups: group 1: 20 mm or less (n = 33), group 2: 21- 30 mm (n = 31); group 3: 31-40 mm (n = 29); group 4: 41-70 mm (n = 42), and group 5: T2 (n = 10). Clinicopathological criteria examined were lymph node and distant metastases, cell type, growth pattern, infiltration pattern, histological grade, local invasion and venous involvement. To identify the optimal cut-off point between T1 and T2 disease the chi2 test was used.

RESULTS

(1) In the clinical series only 1.8% (n = 8) of all cases showed lymph node metastases. Distant metastases were shown in 57 cases (13.04%); within group 1: 0%, group 2: 7.59%, group 3: 1.20%, group 4: 15.76%, group 5: 28%. The tumor grading was statistically correlated with tumor size. (2) In the pathological series 94 of the evaluated 145 patients were downstaged from T2(1987) to T1(1997). Lymph node and distant metastases were well correlated with tumor size. Lymph node metastases were seen in 0, 12.9, 31, 29.3 and 40% (group 1 to group 5) and distant metastases in 12.1, 25.8, 41.4, 47.7 and 60%. There were no statistically significant differences between T2(1997) and T1(3-7 cm). The tumor grading was statistically correlated with tumor size (grade 1: in 66.7, 25.8, 17.2, 9.5 and 0%).

CONCLUSION

Our data suggest that the current cut-off diameter between T1 and T2 renal cell carcinomas (7 cm) is too high. Lowering the cut-off level will result in better discriminatory power of the TNM classification. From our data, we conclude that the cut-off diameter should be lowered to 3.5 cm (p < 0.001).

[Oral adenoid squemous carcinoma. Tumor markers and prognosis]

CASE REPORT

A 58-year-old female patient presented with an exophytic adenoid squamous cell carcinoma on the right alveolar process of the lower jaw. Histological and immunohistochemical differential diagnosis and cellular background of the unfavorable prognosis are described. The patient was treated with curative intent by radical tumor resection including partial mandibulectomy, extensive conservative/radical neck dissection, and postoperative radiation. The adenoid squamous cell carcinoma was classified as pT4, pN0, cM0, R0. During radiation, regional lymph node metastases and distant metastases developed. The patient died of distant metastases 7 months after the initial diagnosis.

HISTOPATHOLOGIC FINDINGS

Tumor cells of adenoid squamous cell carcinoma express epithelial intermediate filament cytokeratin, epithelial membrane antigen (EMA), and epithelial basal membrane protein laminin-5 (Ln-5). Glandular differentiation can be excluded by the absence of epithelial mucins (Alcian blue, mucicarmine). Differentiation from angiosarcoma can be performed using endothelial differential markers CD31, CD34, and factor VIII-associated antigen (FVIII-ass. AG). Both entities are characterized by high proliferation and Ki-67 index of 20%. beta-catenin (cell-cell adhesive protein) loses its primary membrane-bound localization and can explain the histologic pattern of acantholysis. Ln-5 (guide rail of invasion) is massively expressed in adenoid squamous cell carcinoma cells and may be responsible for rapid progression.

CONCLUSIONS

Pseudopapillary proliferation, cellular atypia, vascular-like cavities, expression of cytokeratin, EMA, and Ln-5 are common features of oral adenoid squamous cell carcinoma and angiosarcoma. Diagnosis is determined by the absence of endothelial differential markers CD31, CD34, and FVIII-ass. AG. Modulation of the beta-catenin pattern (transcription factor of Ln-5) and massive expression of invasion factor Ln-5 are suggested as cell biological reasons for rapid progression of adenoid squamous cell carcinoma.

Expression of fibronectin splice variants and oncofetal glycosylated fibronectin in the synovial membranes of patients with rheumatoid arthritis and osteoarthritis

OBJECTIVE

The aim of this study was to define and compare the expression of fibronectin (Fn) isoforms in synovial tissue of patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Using monoclonal antibodies specific for total Fn, extra domain (ED)-A Fn, ED-B Fn, and oncofetal glycosylated Fn, we studied the expression of the Fn isoforms in synovium. Furthermore, in situ hybridization for the detection of ED-B Fn mRNA including a double labeling technique for the detection of cell type was applied.

RESULTS

Strong expression of total Fn, ED-A Fn, oncofetal glycosylated Fn and, to a lesser extent, ED-B Fn could be demonstrated in the synovial lining layer in both RA and OA. Stromal and vessel expression of Fn isoforms was more prominent in RA tissue. Pannus tissue showed strong labeling with ED-B Fn.

CONCLUSION

The expression of alternatively spliced isoforms of Fn is associated with tissue remodeling and, as a partial process of this phenomenon, with neovascularization rather than underlying disease, X-ray status, or parameters of acute inflammation. In the lining layer, Fn expression correlates with hyperplasia associated with cell recruitment but not with proliferative status. Most remarkably, the expression of ED-B Fn in pannus tissue seems to be associated with the invasive phenotype described in RA tissue.

The superficial mandibular gland of the rabbit: a new experimental model for scintigraphic evaluation of salivary glands

The aim of this study was to provide an appropriate experimental model to study functional changes in salivary glands using scintigraphy. Although the rabbit was frequently used for laboratory experiments, there are only a few studies that describe the exact position of its different salivary glands on the sialoscintigram. Twenty rabbits were used for the study; ten of them were anatomically dissected to provide the required topographic anatomy on the different salivary and lacrimal glands. The remaining ten animals underwent a static scintigraphy after extirpation of a particular salivary gland. Changes in the pattern of tracer uptake indicated the exact position of every gland allowing its evaluation. The results show that the 99mTcO4- uptake can only be selectively evaluated in two salivary glands, the superficial mandibular gland and the parotid gland. The superficial mandibular gland was proved to be a particularly useful model to evaluate functional changes of salivary gland parenchyma due to its well defined and high enhanced structure which allows a precise detection and measurement of the tracer uptake. Additionally, the good surgical accessibility of this gland and the existence of a well defined capsule facilitate associated histological studies of its parenchyma.

Cytokine mRNA expression in experimental porcine pneumonia

A porcine Pasteurella multocida (P. m.) infection model was established to study the spatial distribution of cytokine mRNA-expressing cells in lung tissue during acute pneumonia. The mRNA detection was performed by non-radioactive, formamide-free in situ hybridization (ISH) using oligonucleotides against the porcine interleukins (IL): IL-1 beta, IL-2, IL-4, IL-6, IL-8, TNF alpha and TGF beta. Cytokine mRNA-expressing macrophages were demonstrated by a double staining procedure combining immunohistochemistry (IH) using the primary antibody 2G6 with IL-1 beta, IL-6 and TGF beta ISH. With the exception of some stained TNF alpha-expressing cells, no IL mRNA was detectable in the lung of unaffected animals. The experimental P. m. pneumonia was characterized by a predominant, exudative and an additional proliferative interstitial component as well as abscess formation in the lung. Many cells of the region between the abscess membrane and the affected lung area showed high IL-6, IL-1 beta, IL-4 as well as TGF beta and few cells low IL-8 mRNA expression with characteristic distribution patterns. The ISH/IH double staining procedure revealed that at least some of the IL-6 or TGF beta-producing cells belonged to the 2G6-positive macrophages.

Enhancement of the antitumor activity of interleukin-12 by targeted delivery to neovasculature

Interleukin-12 (IL-12) is a heterodimeric cytokine with potent immunostimulatory activity and anti-angiogenic properties. Its clinical applications are limited, however, by severe side-effects. Here we report that an IL-12 fusion protein, consisting of IL-12 fused to a human antibody fragment specific to the oncofetal ED-B domain of fibronectin, markedly enhances the antitumor activity of this cytokine, as demonstrated in a mouse lung-metastasis model and in two models of mice bearing different aggressive murine tumors. The residual small tumor masses seen in the treated mice were infiltrated with lymphocytes, macrophages, and natural killer cells and had elevated interferon gamma (IFN-gamma). These results are of therapeutic relevance as the ED-B domain of fibronectin, a naturally occurring marker of angiogenesis identical in mouse and man, is expressed in the majority of aggressive solid tumors but is not detectable in normal vessels and tissues.

A comparative quantitative analysis of laminin-5 in the basement membrane of normal, hyperplastic, and malignant oral mucosa by confocal immunofluorescence imaging

Laminin-5 (Ln-5) is a heterotrimeric basement membrane (BM) molecule (alpha3beta3gamma2). It is a principal protein constituent of the anchoring filaments, which connect the BM with the hemidesmosomes of the basal keratinocytes and possess a crucial function in keratinocyte adhesion. Confocal immunofluorescence imaging is introduced for a quantitative evaluation of the Ln-5 content in the BM of oral squamous epithelium. The BM of normal oral mucosa was used as a reference (100%) for comparative analysis and showed a nearly uniform Ln-5 immunofluorescence intensity (99-100%). In all hyperplastic lesions of oral mucosa, the Ln-5 immunofluorescence intensity was increased (107-141%). The increased Ln-5 content in the BM of hyperplastic lesions suggests an increased keratinocyte-BM adhesion, possibly resulting in a higher stability of the oral mucosa. In contrast, in the oral squamous cell carcinoma (OSCC) invasive front, the remaining BM segments were characterized by a decrease in Ln-5 immunofluorescence intensity (35-74%). A stronger decrease of Ln-5-linked kerationocyte-BM adhesion correlates with a higher tumor grade. Because in central areas of carcinoma BM segments with a normal Ln-5 content could be demonstrated, the fundamental Ln-5 diminution in BM segments of the invasive front should be considered as an invasion-associated phenomenon.

[Tumors of the face in organ transplant patients]

BACKGROUND

The greatly enhanced risk of developing pre-cancerous lesions, basal cell carcinomas, and squamous cell carcinomas in organ transplant recipients is demonstrated on the basis of three of our own cases.

DISCUSSION

Immunosuppression is discussed as the primary reason for enhanced tumour incidence and the occurrence of multiple synchronic and metachronic tumours after organ transplantation. UV exposition and oncogenic viruses must be taken into account as further factors for tumour disposition. More aggressive tumour behaviour has to be expected. In consequence, a focused clinical monitoring and a stringent therapy of the skin tumours is absolutely necessary.

Clinical manifestation of POEMS syndrome with features of connective tissue disease

The POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) syndrome is a rare plasma cell disease with multiorgan involvement and varying clinical manifestations. We report a 38-year-old man who presented with scleroderma-like skin changes of the hands and feet, sicca and Raynaud's syndrome, pleural effusions, glomerulopathy, polyneuropathy, hepatosplenomegaly and lymphadenopathy. Steroid treatment was started on the assumption of a connective tissue disease and led to a temporary improvement. During the further course of the disease, hypothyreosis, monoclonal gammopathy and osteosclerotic bone lesions were detected, leading to the diagnosis of POEMS syndrome. This case emphasises the need to consider POEMS syndrome as a differential diagnosis in patients with signs of connective tissue disease and polyneuropathy.

Fetal fibronectin: a new screening-marker for bladder cancer?

Early detection of transitional cell carcinoma (TCC) of the urinary bladder is essential for effective treatment. While several serum markers have been evaluated, none have been widely accepted for practical clinical use. Thus, urinary markers have been introduced and investigated to detect the evidence of bladder cancer. But sensitivity and specificity range around 80% respectively. In a prospective study we evaluated fetal fibronectin in the urine of patients with TCC of the urinary bladder. The positivity of oncofetal fibronectin was measured in morning urine samples by membrane immunoassay. This FFN membrane immunoassay is a qualitative test, a solid-phase immunogold assay. A positive sample will result in a single spot after binding of the oncofetal fibronectin-immunogold complex to the membrane containing a monoclonal antibody specific to oncofetal fibronectin (FDC-6, which specifically recognizes III-CS region). The morning urine samples were collected from patients with TCC before they underwent transurethral resection (n=40, 34 non-invasive and 6 invasive carcinomas) and healthy controls (n=20). Oncofetal fibronectin was investigated in the surgical samples by immunohistochemistry (antibody FDC-6, APAAP technique). We found a positive result for oncofetal fibronectin in 38/40 patients with transitional cell carcinoma of the urinary bladder. Two patients with a small pTaG1-TCC showed negative results. In the urine of healthy controls no positive results were detected. Thus, there is a sensitivity of 95% and a specificity of 100%. The TCC was demonstrated as a source of oncfn. To our knowledge this is the first study showing that patients with an evident TCC have a demonstrable amount of oncofetal fibronectin in the urine. We conclude that a positive result is common in TCC-patients. The sensitivity and specificity of this test seems to be extraordinarily high. Because of the small number of cases further studies are required.

Fibrillary co-deposition of laminin-5 and large unspliced tenascin-C in the invasive front of oral squamous cell carcinoma in vivo and in vitro

PURPOSE

Invasion of oral squamous cell carcinoma (OSCC) is associated with laminin-5 (Ln-5) synthesis, focal Ln-5 loss from the basement membrane (BM), and Ln-5 depositions in the stroma beneath invading carcinoma cell complexes.

METHODS

The study is focused on the laminin-5 matrix reorganisation within the stroma of the OSCC invasive front outside the basement membrane region as well as in OSCC-fibroblast co-culture in relation to unspliced tenascin-C (Tn-CL) and ED-B+ fibronectin (ED-B+ fn) using confocal laser scanning microscopy.

RESULTS

In vivo, Ln-5 was demonstrated as fibrillary deposition in the invasive front. It was co-localised to Tn-CL. In pure OSCC cultures, Ln-5 was synthesised and deposited as a spot-like matrix. Fibrillary structures were not found. In contrast, in the OSCC-fibroblast co-culture, a fibrillary Ln-5 matrix organisation was revealed within the interface of OSCC cell-fibroblast complexes exclusively in co-distribution with Tn-CL and ED-B+ fn.

CONCLUSION

At least in vitro, a carcinoma cell-stroma fibroblast interaction is indispensable for fibrillary Ln-5/Tn-CL matrix organisation. Behind the parallels to the initial basement membrane formation in organotypic cultures, the fibrillary multiprotein complexes at the OSCC cell-fibroblast interface are suggested as provisional basement membrane fragments with a possible supportive role for invasive tumour behaviour.

Elevated activity and expression of Src-family kinases in human breast carcinoma tissue versus matched non-tumor tissue

Src-family kinase expression was measured in 52 human mammary tumor (T) specimens compared with non-tumor (NT) tissue from the same patient by enzymatic assays employing a Src-kinase family-specific peptide substrate and by immunoblotting with an antibody recognizing the Src-family kinases Src, Fyn, and Yes. In the T specimens, the mean enzymatic activity was moderately elevated (T: 160 fmol ATP min-1 mg-1; NT: 115 fmol ATP min-1 mg-1) with 25 tumor samples having higher activity than the corresponding NT tissue, 17 having lower activity, and no activity detectable in ten T/NT pairs. Immunoblotting revealed clearly elevated expression in 25 tumor tissues and no differences or expression below the detection limit in the remaining T/NT pairs. The data are in agreement with a possible role of Src-family kinases for the biology of mammary carcinoma.