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The influence of 17-β-estradiol, tamoxifen and ICI 182, 780 on the integrin expression alpha 3, alpha 6, beta 1 and beta 4 in oscc
Oral Presentations / 044. Distraction Osteogenesis III
81
OSCC. Their advantages are: bactericidical activity, broad antibacterial spectrum including Gram-positive cocci and anaerobes and positive pharmacocinetics.
[•3•
THE INFLUENCE OF 17-1~-ESTRADIOL, TAMOXIFEN AND ICI 182,780 ON THE INTEGRIN EXPRESSION ALPHA 3, ALPHA 6, BETA 1 AND BETA 4 IN OSCC
K. Nelson, V. Helmstaedter, H. Lage. Clinic for Oral and Maxillofacial
Surgery and Clinical Navigation and Robotics, CharitY-Campus Virchow Clinic, Humboldt-University Augustenburger Platz 1, 13353 Berlin, Germany Biological activity of steroid hormones and their antagonists on cancer cells is extensively studied for the reproductive tissues, it has become clear that not only cells of the reproductive tissues but also melanoma cells and neuronal cells are affected by these compounds. It is assumed that the altered integrin expression observed in oral squamous cell carcinomas (OSCC) contribute to the invasive behavior. Little is known about the mechanism of action of estradiol, Tamoxifen and Faslodex on non-reproductive organs and neoplasms as well as their influence on the expression of certain integrins. We have studied the effects of estradiol, tamoxifen and faslodex in in vitro experiments on the integrin expression in established OSCC cell lines (UM-SCC 14A, 14B and 14C) on the mRNA level measured by Northern Blot and quantitative real time RT-PCR as well as on protein level determined by flow cytometry and immunofluorescence. We found significant changes of the transcription of the I-~l-integrin subunit, suggesting a regulation at the transcriptional level. Whereas alterations only in cell surface expression but not at the transcriptional level of a certain integrin subunit could be demonstrated for alpha 3. We could show an alteration in integrin expression in OSCC in vitro indicating that cell behavior (e.g. motility) in non-reproductive organs might also be regulated under the influence of hormones. Further investigations may elucidate the mechanism of action of estradiol and antiestrogens and might lead to new avenues for the use of antiestrogens as adjuvant therapy in patients with OSCC.
[ - 6 - ~ - - ~ RELEVANCE OF TUM2-PYRUVATE KINASE AS MARKER OF EARLY CANCER OF THE ORAL CAVITY J. Ervens 1, H. Fuchs 2, B. Hoffmeister1. 1D, .Department of Maxillofacial
and Facial Plastic Surgery; 2Department of Clinical Chemistry and Pathobiochemistry, Charit~ - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, D-12200 Berlin, Germany Circulating tumor markers are an established method for early detection and disease monitoring of many malignant tumors. The metabolic state of tumor cells differs from normal proliferating cells, in particular tumor cells exhibit an increased aerobic glycolysis in which pyruvat kinase is one of the glycolytic key enzymes. The dimeric form of the M2-pyruvate kinase is increased in tumor cells and therefore called TumorM2-pyruvate kinase (TuM2-PK). The aim of the present, prospective study was to evaluate the diagnostic relevance of TuM2-PK in the detection of oral squamous cell carcinoma (OSCC). In a prospective study concentration of TuM2-PK was analyzed in EDTA plasma of 80 untreated patients with histologically confirmed squamous cell cancer (T3 and T4) and 90 patients with non malignant diseases served as a control group. Immunohistochemical detection of TuM2-PK was performed by specific mouse monoclonal antibody DF-4. Significance of the difference of the means was calculated with the Mann-Whitney test for non parametric distribution. The median of TuM2-PK concentration of the tumor group was 23 U/ml compared to 10 U/ml in the control group (p <0.001). Use of the cut-off of 15U/ml, sensitivity and specificity was 63% and 59% respectively. Additonally, positive and negative predictive value was 58% and 64% respectively. Immunohistochemical staining on tissue sections of histologically confirmed oral squamous cell carcinomas showed no selective staining of tumor cells, but increased staining of all highly regenerate tissues. Due to low sensitivity and specificity for OSCC at stage T3 and T4, the TuM2-PK test is no suitable tool in the detection of OSCC, in particular in the diagnosis of OSCCs in an early stage. Thus, clinical and radiological follow-up routinely after oncologic treatment of OSCC is indispensable.
044. Distraction Osteogenesis III
•0--•-'•
EFFECT OF DISTRACTION RATES ON EXPRESSION OF TISSUE INHIBITORS OF MATRIX METALLOPROTEINASES IN RABBIT MANDIBULAR DISTRACTION OSTEOGENESIS
L.W. Zheng, L. Ma, L.K. Cheung. Department of Oral & Maxillofacial
Surgery, Faculty of Dentistry, the University of Hong Kong, China, Hong Kong SAR, China Bone induction and ossification in distraction osteogenesis is related to the biological environment created by the mechanical tension. When compared with distraction at a normal rate, rapid distraction has demonstrated unreliable bone healing. Tissue inhibitors of matrix metalloproteinases (TIMPs) are nature inhibitors of matrix metalloproteinases (MMPs), which are capable of degrading bone matrix during the remodeling process. We hypothesize that different distraction rates may produce different TIMPs expression patterns, which will ultimately lead to different results in bone formation and remodeling. This study aims to compare the expression of endogenous TIMP-1 and -2 during rabbit mandibular distraction osteogenesis at normal and rapid rates. 27 New Zealand white rabbits were used. 24 rabbits were divided into 2 experimental groups with 12 rabbits in each group. Mandibular distraction was activated at 0.9mm/day lasting 12 days in the normal distraction group, and at 2.7 mm/day lasting 4 days in the rapid distraction group. 3 rabbits in each experimental group were sacrificed at day 1, week 1, week 2, and week 4 of consolidation. The other 3 rabbits without performing operation were used as control. Mandibular specimens were subjected for histological and Immunohistochemical assessment. The cells expressing TIMP-1 and -2 within the distraction regenerate were counted using a computer assisted image analyzing system. Histological study identified that normal rate distraction (0.9 mm/day) led to complete bone healing, whereas unreliable bone ossification was confirmed at rapid distraction (2.7 mm/day). The expression of TIMP-2 and -2 was localized in the osteoblasts, osteocytes and bone matrices of the trabeculae. Continuous up-regulation of TIMP-1 and -2 was observed in normal rate distraction group, whereas in the rapid lengthening model, TIMP-1 and -2 expression returned to a near-normal level at 4 weeks of consolidation. The change in the mechanical environment resulting from different rates of distraction leads to different expression of the TIMP-1 and -2 during mandibular distraction osteogenesis. The biological environment created by distraction at a normal rate is superior to the rapid distraction rate.
[•
PULSED VERSUS CONTINUOUS LOW-INTENSITY ULTRASOUND STIMULATION IN DISTRACTION OSTEOGENESIS IN RABBITS
R.F. Elgazzar, £H. EI-Bialy, I.E. Megahed, £J. Royston. Oral and Maxillofacial Surgery Department, Faculty of Dentistry, Tanta University, Tanat, Egypt Several investigations have reported on the stimulatory effect of transcutaneous low-intensity ultrasound (US) treatment on distraction osteogenesis and fracture healing. The objective of this work was to study if there is any difference of the stimulatory effect of pulsed ultrasound (PUS) compared to continuous one (CUS) in rabbits. Twenty-four New Zealand, skeletally mature, male rabbits were divided into 3 groups 8 animals each. After bilateral mandibular body osteotomy, a custommade distraction device was used for each rabbit. 72 hours after surgery, the distraction appliances were activated by opening the screws 1.5 mm each 12 hours for 5 days. The 1st study group was treated with PUS (200 pulse of 1.5 MHz at 1.1 kHz frequency for 20 min every day), the 2nd study group was treated with CUS of the same frequency and output power for 20 min every day, the control group did not receive any US treatment. Experimental, histopathological and histomorphometric analysis were undertaken at 1, 2, 3, and 4 weeks after distraction. In all rabbits, both types of US (continuous and pulsed) produced better bone formation than in the distraction group without US treatment. In the first two weeks after finishing distraction, differences between the CUS and PUS groups were statistically insignificant. However, by the 3rd and 4th weeks after finishing distraction, PUS produced statistically significant better bone formation than CUS as indicated by the increase in the number and size of bony trabeculae at the distraction zone. We
81
OSCC. Their advantages are: bactericidical activity, broad antibacterial spectrum including Gram-positive cocci and anaerobes and positive pharmacocinetics.
[•3•
THE INFLUENCE OF 17-1~-ESTRADIOL, TAMOXIFEN AND ICI 182,780 ON THE INTEGRIN EXPRESSION ALPHA 3, ALPHA 6, BETA 1 AND BETA 4 IN OSCC
K. Nelson, V. Helmstaedter, H. Lage. Clinic for Oral and Maxillofacial
Surgery and Clinical Navigation and Robotics, CharitY-Campus Virchow Clinic, Humboldt-University Augustenburger Platz 1, 13353 Berlin, Germany Biological activity of steroid hormones and their antagonists on cancer cells is extensively studied for the reproductive tissues, it has become clear that not only cells of the reproductive tissues but also melanoma cells and neuronal cells are affected by these compounds. It is assumed that the altered integrin expression observed in oral squamous cell carcinomas (OSCC) contribute to the invasive behavior. Little is known about the mechanism of action of estradiol, Tamoxifen and Faslodex on non-reproductive organs and neoplasms as well as their influence on the expression of certain integrins. We have studied the effects of estradiol, tamoxifen and faslodex in in vitro experiments on the integrin expression in established OSCC cell lines (UM-SCC 14A, 14B and 14C) on the mRNA level measured by Northern Blot and quantitative real time RT-PCR as well as on protein level determined by flow cytometry and immunofluorescence. We found significant changes of the transcription of the I-~l-integrin subunit, suggesting a regulation at the transcriptional level. Whereas alterations only in cell surface expression but not at the transcriptional level of a certain integrin subunit could be demonstrated for alpha 3. We could show an alteration in integrin expression in OSCC in vitro indicating that cell behavior (e.g. motility) in non-reproductive organs might also be regulated under the influence of hormones. Further investigations may elucidate the mechanism of action of estradiol and antiestrogens and might lead to new avenues for the use of antiestrogens as adjuvant therapy in patients with OSCC.
[ - 6 - ~ - - ~ RELEVANCE OF TUM2-PYRUVATE KINASE AS MARKER OF EARLY CANCER OF THE ORAL CAVITY J. Ervens 1, H. Fuchs 2, B. Hoffmeister1. 1D, .Department of Maxillofacial
and Facial Plastic Surgery; 2Department of Clinical Chemistry and Pathobiochemistry, Charit~ - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, D-12200 Berlin, Germany Circulating tumor markers are an established method for early detection and disease monitoring of many malignant tumors. The metabolic state of tumor cells differs from normal proliferating cells, in particular tumor cells exhibit an increased aerobic glycolysis in which pyruvat kinase is one of the glycolytic key enzymes. The dimeric form of the M2-pyruvate kinase is increased in tumor cells and therefore called TumorM2-pyruvate kinase (TuM2-PK). The aim of the present, prospective study was to evaluate the diagnostic relevance of TuM2-PK in the detection of oral squamous cell carcinoma (OSCC). In a prospective study concentration of TuM2-PK was analyzed in EDTA plasma of 80 untreated patients with histologically confirmed squamous cell cancer (T3 and T4) and 90 patients with non malignant diseases served as a control group. Immunohistochemical detection of TuM2-PK was performed by specific mouse monoclonal antibody DF-4. Significance of the difference of the means was calculated with the Mann-Whitney test for non parametric distribution. The median of TuM2-PK concentration of the tumor group was 23 U/ml compared to 10 U/ml in the control group (p <0.001). Use of the cut-off of 15U/ml, sensitivity and specificity was 63% and 59% respectively. Additonally, positive and negative predictive value was 58% and 64% respectively. Immunohistochemical staining on tissue sections of histologically confirmed oral squamous cell carcinomas showed no selective staining of tumor cells, but increased staining of all highly regenerate tissues. Due to low sensitivity and specificity for OSCC at stage T3 and T4, the TuM2-PK test is no suitable tool in the detection of OSCC, in particular in the diagnosis of OSCCs in an early stage. Thus, clinical and radiological follow-up routinely after oncologic treatment of OSCC is indispensable.
044. Distraction Osteogenesis III
•0--•-'•
EFFECT OF DISTRACTION RATES ON EXPRESSION OF TISSUE INHIBITORS OF MATRIX METALLOPROTEINASES IN RABBIT MANDIBULAR DISTRACTION OSTEOGENESIS
L.W. Zheng, L. Ma, L.K. Cheung. Department of Oral & Maxillofacial
Surgery, Faculty of Dentistry, the University of Hong Kong, China, Hong Kong SAR, China Bone induction and ossification in distraction osteogenesis is related to the biological environment created by the mechanical tension. When compared with distraction at a normal rate, rapid distraction has demonstrated unreliable bone healing. Tissue inhibitors of matrix metalloproteinases (TIMPs) are nature inhibitors of matrix metalloproteinases (MMPs), which are capable of degrading bone matrix during the remodeling process. We hypothesize that different distraction rates may produce different TIMPs expression patterns, which will ultimately lead to different results in bone formation and remodeling. This study aims to compare the expression of endogenous TIMP-1 and -2 during rabbit mandibular distraction osteogenesis at normal and rapid rates. 27 New Zealand white rabbits were used. 24 rabbits were divided into 2 experimental groups with 12 rabbits in each group. Mandibular distraction was activated at 0.9mm/day lasting 12 days in the normal distraction group, and at 2.7 mm/day lasting 4 days in the rapid distraction group. 3 rabbits in each experimental group were sacrificed at day 1, week 1, week 2, and week 4 of consolidation. The other 3 rabbits without performing operation were used as control. Mandibular specimens were subjected for histological and Immunohistochemical assessment. The cells expressing TIMP-1 and -2 within the distraction regenerate were counted using a computer assisted image analyzing system. Histological study identified that normal rate distraction (0.9 mm/day) led to complete bone healing, whereas unreliable bone ossification was confirmed at rapid distraction (2.7 mm/day). The expression of TIMP-2 and -2 was localized in the osteoblasts, osteocytes and bone matrices of the trabeculae. Continuous up-regulation of TIMP-1 and -2 was observed in normal rate distraction group, whereas in the rapid lengthening model, TIMP-1 and -2 expression returned to a near-normal level at 4 weeks of consolidation. The change in the mechanical environment resulting from different rates of distraction leads to different expression of the TIMP-1 and -2 during mandibular distraction osteogenesis. The biological environment created by distraction at a normal rate is superior to the rapid distraction rate.
[•
PULSED VERSUS CONTINUOUS LOW-INTENSITY ULTRASOUND STIMULATION IN DISTRACTION OSTEOGENESIS IN RABBITS
R.F. Elgazzar, £H. EI-Bialy, I.E. Megahed, £J. Royston. Oral and Maxillofacial Surgery Department, Faculty of Dentistry, Tanta University, Tanat, Egypt Several investigations have reported on the stimulatory effect of transcutaneous low-intensity ultrasound (US) treatment on distraction osteogenesis and fracture healing. The objective of this work was to study if there is any difference of the stimulatory effect of pulsed ultrasound (PUS) compared to continuous one (CUS) in rabbits. Twenty-four New Zealand, skeletally mature, male rabbits were divided into 3 groups 8 animals each. After bilateral mandibular body osteotomy, a custommade distraction device was used for each rabbit. 72 hours after surgery, the distraction appliances were activated by opening the screws 1.5 mm each 12 hours for 5 days. The 1st study group was treated with PUS (200 pulse of 1.5 MHz at 1.1 kHz frequency for 20 min every day), the 2nd study group was treated with CUS of the same frequency and output power for 20 min every day, the control group did not receive any US treatment. Experimental, histopathological and histomorphometric analysis were undertaken at 1, 2, 3, and 4 weeks after distraction. In all rabbits, both types of US (continuous and pulsed) produced better bone formation than in the distraction group without US treatment. In the first two weeks after finishing distraction, differences between the CUS and PUS groups were statistically insignificant. However, by the 3rd and 4th weeks after finishing distraction, PUS produced statistically significant better bone formation than CUS as indicated by the increase in the number and size of bony trabeculae at the distraction zone. We