Klaus Laimer

TROP2: a novel prognostic marker in squamous cell carcinoma of the oral cavity

Squamous cell carcinoma is by far the most common type of cancer of the oral cavity, representing more than 90% of all oral cancers. Despite refinement of surgical techniques and adjuvant therapies, the prognosis for patients with oral squamous cell carcinoma remains poor. Identification of prognostic factors related to tumor biology might improve this assessment. Recently, the human trophoblast cell-surface antigen TROP2 was found to be highly expressed in colorectal cancer, correlating with aggressiveness and poor prognosis. Thus, the aim of this study was to investigate TROP2 expression and its prognostic impact in oral squamous cell carcinoma patients. TROP2 expression was examined by immunohistochemistry in a series of 90 patients on a tissue microarray of paraffin-embedded specimens. Survival was calculated using Kaplan–Meier estimates. Parameters found to be of prognostic significance in univariate analysis were verified in a multivariate Cox regression model. TROP2 overexpression was observed in 52 (58%) of the tumor samples. Kaplan–Meier curves showed that TROP2 overexpression was significantly associated with decreased overall survival (P<0.01). Overall survival gradually worsened with increasing TROP2 scores. By univariate analyses, no correlation with conventional clinicopathological features was found. Multivariate Cox regression analysis revealed TROP2 overexpression to be an independent factor predictive of poor disease outcome (P<0.01). These results demonstrate that TROP2 overexpression is an independent prognostic marker in patients with oral squamous cell carcinoma. TROP2 overexpression was detectable in 58% of the tumor samples, indicating it to be a potential novel therapeutic target in squamous cell carcinoma of the oral cavity.

The role of oxygen termination of nanocrystalline diamond on immobilisation of BMP-2 and subsequent bone formation

Medical implants are increasingly often inserted into bone of frail patients, who are advanced in years. Due to age, severe trauma or pathology-related bone changes, osseous healing at the implant site is frequently limited. We were able to demonstrate that coating of endosseous implants with nanocrystalline diamond (NCD) allows stable functionalization by means of physisorption with BMP-2. Strong physisorption was shown to be directly related to the unique properties of NCD, and BMP-2 in its active form interacted strongly when NCD was oxygen-terminated. The binding of the protein was monitored under physiological conditions by single molecule force spectroscopy, and the respective adsorption energies were further substantiated by force-field-calculations. Implant surfaces refined in such a manner yielded enhanced osseointegration in vivo, when inserted into sheep calvaria. Our results further suggest that this technical advancement can be readily applied in clinical therapies with regard to bone healing, since primary human mesenchymal stromal cells strongly activated the expression of osteogenic markers when being cultivated on NCD physisorbed with physiological amounts of BMP-2.

Ep-CAM expression in pancreatic and ampullary carcinomas: frequency and prognostic relevance

Aims: Pancreatic adenocarcinoma is an aggressive gastrointestinal malignancy with only a few long-term survivors even after radical surgery. Patients with ampullary cancer have a better prognosis but adjuvant therapy needs further improvement. Epithelial cell adhesion molecule (Ep-CAM) is strongly expressed in a variety of epithelial cancers and represents a promising target for immunological tumour therapy. Thus, the aim of this study was to investigate Ep-CAM expression and its potential prognostic impact in pancreatic and ampullary carcinomas. Methods: Ep-CAM expression was investigated retrospectively by immunohistochemistry in paraffin-embedded primary tumour tissue samples from a series of consecutive patients with pancreatic (n = 153) and ampullary cancer (n = 34). Results: Ep-CAM overexpression was observed in 85 of 153 pancreatic cancer specimens (56%) and in 29 of 34 ampullary cancer samples (85%). Overall, Ep-CAM failed to be an independent prognostic marker. However, subgroup analyses showed that Ep-CAM overexpression correlated with shorter overall survival among patients with ampullary cancer and advanced stage pancreatic cancer. In the latter subgroup, survival gradually worsened with increasing Ep-CAM scores. Furthermore, in ampullary cancer, Ep-CAM overexpression was found to correlate with tumour stage. Conclusions: Ep-CAM overexpression was detectable in the majority of cases with pancreatic and ampullary cancer. Therefore, Ep-CAM represents an attractive target for immune-based therapeutic interventions in these tumour entities. However, the prognostic value of Ep-CAM overexpression remains undetermined.

STAT1 activation in squamous cell cancer of the oral cavity: a potential predictive marker of response to adjuvant chemotherapy.

For patients with squamous cell carcinoma of the oral cavity, both locoregional and distant recurrences are common, and an appropriate adjuvant treatment modality has yet to be defined. Thus, there is an urgent need to identify novel molecular markers with potential prognostic and/or predictive value to improve treatment outcome in these patients. This retrospective study was designed to investigate the predictive and/or prognostic value of STAT1 activation in squamous cell carcinoma of the oral cavity.

High expression of prostate-specific membrane antigen in the tumor-associated neo-vasculature is associated with worse prognosis in squamous cell carcinoma of the oral cavity

Prostate-specific membrane antigen (PSMA) is a transmembrane protein expressed in prostate cancer as well as in the neo-vasculature of nonprostatic solid tumors. Here, we determined the expression pattern of PSMA in the vasculature of oral squamous cell carcinoma. Using a previously validated antibody, PSMA staining distribution and cyclooxygenase 2 (COX2) expression status was evaluated in a cohort of patients with squamous cell carcinoma of the oral cavity (n=96) using immunohistochemistry and was correlated with clinicopathological features as well as outcome. Twenty-four (25%) cases showed no detectable PSMA staining, 48 (50%) demonstrated positive immunoreactivity for PSMA in less than 50% of microvessels and 24 (25%) cases showed strong endothelial PSMA expression in more than 50% of tumor-associated microvessels. High endothelial PSMA expression was associated with greatly reduced survival (18.2 vs 77.3 months; P=0.0001) and maintained prognostic significance after adjusting for grade and stage in multivariate analysis (hazard ratio=2.19, P=0.007). Furthermore, we observed a strong association between endothelial PSMA and cancer cell-specific COX2 expression. In conclusion, we provide the first evidence for the prognostic significance of endothelial PSMA expression in oral squamous cell carcinoma and, suggest a potential interaction between arachidonic acid metabolites and endothelial PSMA expression in the tumor neo-vasculature.

Traumatic intracranial haemorrhage in conscious patients with facial fractures – A review of 1959 cases

OBJECTIVE Facial fracture patients who are conscious with a Glasgow Coma Scale (GCS) score of 15 in the absence of clinical neurological abnormalities are commonly not expected to have suffered severe intracranial pathology. However, high velocity impact may result in intracranial haemorrhage in different compartments. METHODS Over a 7-year period, 1959 facial fracture patients with GCS scores of 15 and the absence of neurological abnormalities were analysed. In 54 patients (2.8%) computed tomography scans revealed the presence of accompanying intracranial haemorrhage (study group). These patients were compared with the 1905 patients without intracranial haemorrhage (control group). RESULTS Univariate analysis identified accompanying vomiting/nausea and seizures, cervical spine injuries, cranial vault and basal skull fractures to be significantly associated with intracranial bleeding. In multivariate analysis the risk was increased nearly 25-fold if an episode of vomiting/nausea had occurred. Seizures increased the risk of bleeding more than 15-fold. The mean functional outcome of the study group according to the Glasgow Outcome Scale was 4.7+/-0.7. CONCLUSION Intracranial haemorrhage cannot be excluded in patients with facial fractures despite a GCS score of 15 and normal findings following neurological examination. Predictors, such as vomiting/nausea or seizures, skull fractures and closed head injuries, enhance the likelihood of an intracranial haemorrhage and have to be considered.

Expression and prognostic impact of indoleamine 2,3-dioxygenase in oral squamous cell carcinomas.

Indoleamine 2,3 dioxygenase (IDO) is a negative immune regulator and was found to be a prognostic marker in several tumor entities. In this study, we analysed IDO expression in oral squamous cell carcinoma (OSCC) regarding patients prognosis. Additionally, expression of IDO like-1 gene (INDOL-1) was analysed. Tumor tissue from 88 patients with OSCC was analysed by immunohistochemistry for IDO expression. The influence of IDO expression on survival was studied by multivariate Cox regression, adjusting for established clinical prognostic parameters. Real time PCR of tumor samples was performed in a subgroup of patients to analyse mRNA expression of IDO and INDOL-1. IDO high-expression was observed in 44.2% of OSCC patients. No significant correlation was found between IDO expression and clinical stage, sex, age, tumor site, tumor size, metastasis or tumor grade. The median overall survival time was 3.1 years for patients with IDO low tumors, compared to 1.36 years for IDO high tumors (P=.028). Subset analysis of patients receiving adjuvant radio-chemotherapy showed a significant difference (P=.0046) in overall survival between IDO low tumors (3.35 years) and IDO high tumors (1.26 years). In contrast, the impact of IDO expression on survival time in patients without adjuvant therapy was not significant (P=.574). Interestingly, INDOL-1 was not expressed in OSCC. IDO high expression represents a significant negative prognostic factor in patients with OSCC, especially in those patients undergoing adjuvant radiochemotherapy. Our data support the suggestion, co-administration of small-molecule IDO inhibitors could represent a promising new strategy to increase the anti-tumor activity of radio-chemotherapy in patients with IDO positive OSCC.

High resolution ultrasound investigation of the temporomandibular joint in patients with chronic polyarthritis

40 patients with chronic polyarthritis were investigated prospectively. The TMJ was investigated to detect clicking, crepitation, and pain. High resolution ultrasound (HR-US) assessed destructive changes, effusion, and disc dislocation. The results of the clinical investigation and the HR-US investigation were compared using the χ(2) test. The statistical calculation of the correlation between the HR-US results and the clinical TMJ investigation by the χ(2) test showed a significant correlation between TMJ sounds, destructive changes and disc dislocation. A significant correlation between TMJ joint effusion, TMJ pathology and TMJ pain was detected using the χ(2) test. Pain on palpation of the masseter and temporal muscle correlated significantly with TMJ effusion. There was significant correlation between TMD and the HR-US diagnosis of destructive changes and effusion. The significant correlation between TMJ effusion and actual TMJ pain and TMJ pain on palpation shows the ability of HR-US to detect acute TMJ affection with high significance. There was a significant correlation between effusion and pain on palpation of the masticatory muscles, which could be interpreted as the ability of HR-US to determine acute TMD. That any TMD correlated significantly with destructive changes and TMJ effusion suggests that HR-US could detect chronic and acute TMD.

Facial Trauma: How Dangerous Are Skiing and Snowboarding?

PURPOSE The aim of this study was to investigate maxillofacial injuries sustained in both skiing and snowboarding accidents and correlate injury mechanisms and patterns evaluating a large population. MATERIALS AND METHODS Between 1991 and 2003, all patients with maxillofacial injuries due to skiing and snowboarding accidents (1,393 cases) were reviewed and statistically analyzed according to age, gender, type of injury, cause of accident, location of trauma, and associated injuries. RESULTS Skiing accidents resulted in a total of 1,250 injuries, and snowboarding resulted in 143. In this study 686 skiers presented with 1,452 facial bone fractures and 80 snowboarders sustained 160 fractures of the face. Skiers had dentoalveolar trauma in 810 cases and 1,295 soft tissue injuries, whereas snowboarders had 88 dental injuries and 187 soft tissue lesions. Mechanisms of injury included 542 cases due to skiing and 85 falls due to snowboarding (a 1.79-fold higher risk for snowboarders). The gender distribution showed a male-female ratio of 3:1 in skiers and 5.5:1 in snowboarders. In both groups male patients were more prone to have a facial bone fracture than female patients. Snowboarders aged between 10 and 29 years had a 2.14-fold higher risk of sustaining a maxillofacial injury than skiers. CONCLUSIONS In both groups facial bone fractures occurred more often in male patients, and they were more likely to result from falls and collisions with other persons. Young snowboarders had a higher risk of maxillofacial injuries (especially soft tissue lesions) than skiers, whereas for children and old persons, skiing posed a much higher risk. Wearing a helmet while skiing and snowboarding should be mandatory to prevent serious trauma to the head.

Overexpression of eIF3a in Squamous Cell Carcinoma of the Oral Cavity and Its Putative Relation to Chemotherapy Response

The eukaryotic translation initiation factor eIF3a is one of the core subunits of the translation initiation complex eIF3, responsible for ribosomal subunit joining and mRNA recruitment to the ribosome. It is known to play an important role in general translation initiation as well as in the specific translational regulation of various gene products, among which many influence tumour development, progression, and the therapeutically important pathways of DNA damage repair. Therefore, beyond its role in protein synthesis, eIF3a is emerging as regulator in tumour pathogenesis and therapy response and, therefore, a potential tumor marker. By means of a tissue microarray (TMA) for histopathological and statistical assessment, we here show eIF3a expression in 103 cases of squamous cell carcinoma of the oral cavity (OSCC), representing tissues from 103 independent patients. A subset of the study cohort was treated with platinum based therapy. Our results show that the 170 kDa protein is upregulated in OSCC and correlates with good overall survival. Overexpressing tumors respond better to platinum-based chemotherapy, suggesting eIF3a as a putative predictive as well as prognostic tumor marker in OSCC.