Cornelia Czembirek

Betulinic Acid a Radiosensitizer in Head and Neck Squamous Cell Carcinoma Cell Lines

Background and Purpose:Betulinic acid, a pentacyclic triterpene, is a new cytotoxic compound active on melanoma, neuroblastoma, glioblastoma and head and neck squamous cell carcinoma (HNSCC) cells. In combination with irradiation it has been shown to have an additive effect on growth inhibition in melanoma cells. In this study, the radiosensitizing effect of betulinic acid on sequential irradiation was investigated in HNSCC cell lines.Material and Methods:Two HNSCC cell lines, SCC9 and SCC25, were treated with increasing doses of betulinic acid and sequentially irradiated with a single boost of 4 Gy from a conventional radiation source. The cells were counted, the surviving fraction was determined, and colony-forming assays were performed.Results:It could be shown that betulinic acid alone inhibits cell survival, affects cell survival additively in combination with irradiation and decreases clonogenic survival in both cell lines when applied alone.Conclusion:Betulinic acid could be a promising treatment agent in radioresistant head and neck cancer. A combination of betulinic acid with radiotherapy seems to be beneficial.ZusammenfassungHintergrund und Ziel:Betulinsäure, ein pentazyklisches Triterpenoid, ist ein neuer zytotoxischer Wirkstoff mit Wirkung gegen Melanom-, Neuroblastom-, Glioblastom- sowie Kopf- und Halstumorzellen. In Kombination mit Radiotherapie zeigte sich ein additiver Effekt auf die Wachstumshemmung in Melanomzellen. In dieser Studie wurde untersucht, ob Betulinsäure ein Radiosensitizer bei sequentieller Bestrahlung von Kopf- und Halstumorzellen ist.Material und Methodik:Die beiden Kopf- und Halstumorzelllinien SCC9 und SCC25 wurden mit ansteigenden Dosen von Betulinsäure und sequentieller Radiotherapie mit einer Einzeldosis von 4 Gy (Abbildungen 1a und 1b) an einem konventionellen Bestrahlungsgerät behandelt. Dann wurden die Zellen gezählt, das Überleben bestimmt (Abbildungen 2a und 2b) und Koloniebildungsassays durchgeführt (Abbildungen 3a und 3b). Die immunhistochemische Untersuchung erfolgte mit dem M30-Antikörper zur Visualisierung der Apoptose (Abbildungen 4a und 4b).Ergebnisse:Es konnte gezeigt werden, dass Betulinsäure allein das Zellüberleben inhibiert, additiv in Kombination mit Radiotherapie agiert und in beiden Zelllinien die Koloniebildungsfähigkeit herabsetzt.Schlussfolgerung:Betulinsäure könnte ein vielversprechendes Chemotherapeutikum bei radiotherapieresistenten Kopf- und Halstumoren sein. Eine Kombination von Betulinsäure und Strahlentherapie scheint vorteilhaft.

Radiosensitization of head and neck cancer cells by the phytochemical agent sulforaphane

Background and PurposeSulforaphane is a naturally occurring compound found in broccoli and other cruciferous vegetables. Recently it gained attention because of its antiproliferative properties in many cancer cell lines. The aim of this study was to investigate whether sulforaphane could act as a radiosensitizer in head and neck squamous cell carcinoma cell lines.Materials and MethodsFour head and neck squamous cell carcinoma cell lines (i.e., (HNSCC) SCC9, SCC25, CAL27, and FADU) were treated with sulforaphane and subsequently irradiated. Then proliferation and clonogenic assays were performed. Apoptosis was detected by flow cytometry. Possible regulation of Akt and Mcl-1 was investigated by western blotting.ResultsSulforaphane and radiation in combination leads to stronger inhibition of cell proliferation and of clonogenic survival than each treatment method alone. Western blot analysis of Akt and Mcl-1 showed no changed expression.ConclusionSulforaphane is a promising agent in the treatment of head and neck cancer due to its antiproliferative and radio-sensitizing properties. A combination of sulforaphane and radiation decreases clonogenic survival. Apoptosis is not regulated through Akt or the Mcl-1 protein.ZusammenfassungHintergrund und ZielSulforaphan ist ein natürlicher, in Brokkoli und anderen Kreuzblütlern vorkommender Wirkstoff. In letzter Zeit gewann er Beachtung wegen seiner antiproliferativen Wirkung in vielen Zelllinien unterschiedlicher Malignomarten. Ziel dieser Studie war, Sulforaphan auf seine strahlensensibilisierende Wirksamkeit in Kopf- und Halstumorzellen zu erforschen.Material und MethodenVier Kopf- und Halstumorzelllinien (SCC9, SCC25, CAL27, und FADU) wurden mit Sulforaphan behandelt und anschließend bestrahlt. Dann wurden Proliferations- und Clonogenic Assays durchgeführt. Die Apoptose wurde mittels Durchflusszytometrie gemessen. Eine mögliche Regulation von Akt und Mcl-1 wurde mittels Western Blotting untersucht.ErgebnisseSulforaphan und Bestrahlung in Kombination führten zu einer stärker inhibierten Proliferation und Koloniebildung als die einzelnen Behandlungsmethoden allein. Die Western-Blot-Analyse zeigte keine veränderte Expression von Akt und Mcl-1.SchlussfolgerungSulforaphan ist aufgrund seiner antiproliferativen und strahlensensibiliserenden Eigenschaften ein vielver-sprechender Wirkstoff für die Behandlung von Kopf- und Halstumoren. Die Kombination von Sulforaphan und Bestrahlung führt zu einem verminderten klonogenen Überleben. Die Apoptose wird weder durch Akt noch durch Mcl-1 reguliert.

Impact of elective neck dissection on regional recurrence and survival in cN0 staged oral maxillary squamous cell carcinoma.

To evaluate the impact of elective neck dissection (END) on regional recurrence and survival in cN0 staged patients with maxillary squamous cell carcinoma (SCC). Eighty-six patients with maxillary SCC and clinically staged N0 cervical lymph-nodes were evaluated in this single center retrospective study. Seventy-four of 86 patients were included in this analysis, of which 36 patients were treated with END, 38 without END. Following END, pathohistologically verified regional lymph-nodes in the initially cN0 neck were found in three (8%) patients. In both the +END and non-END group regional recurrences occurred exclusively in patients with T4 primaries. The overall regional recurrence rate was 17% in the +END and 18% in the non-END group, respectively. The 5-year overall survival rate for all tumor stages combined (T1-T4) was 86% in the +END group and 82% in the -END group. Within the patients groups with T4 tumors, 5-year overall survival was 81% for the +END group and 56% for the -END group. Over all tumor stages combined (T1-T4), END did not significantly improve overall survival rates and did not prevent the rate of regional recurrence in cN0 staged patients with maxillary alveolar, gingival and palatal SCC. However, in the subgroup of patients with locally advanced T4 tumors, their seemed to be a clear tendency towards improvement of overall survival in the END group. END can therefore be recommended for these patients.

The Cyclooxygenase-2 Inhibitor Nimesulide, a Nonsteroidal Analgesic, Decreases the Effect of Radiation Therapy in Head-and-Neck Cancer Cells

Background:No data are available on the effects of the cyclooxygenase-2 (COX-2) inhibitor nimesulide in combination with irradiation on the survival of head-and-neck carcinoma cells.Material and Methods:Two head-and-neck carcinoma cell lines (SCC9 and SCC25) were treated with nimesulide (50–600 μM) and irradiated concomitantly or sequentially. Early effects on cell survival were investigated by counting cell numbers, long-term effects by colony-forming assays. Cell-cycle effects were analyzed 24–72 h after treatment with nimesulide by flow cytometry.Results:Unexpectedly, nimesulide solely inhibited cell proliferation without affecting colony-forming ability. In addition, no evidence for a radiosensitizing effect of nimesulide in short-term assays was seen. Nimesulide alone had no effect on clonogenic survival alone or in combination with radiation.Conclusion:Nimesulide differentially affects cell proliferation and clonogenic survival and may decrease the efficacy of radiotherapy. Short-term assays to assess tumor growth may not correctly predict the clinically relevant long-term effect of COX-2 inhibitors.Hintergrund:Bis dato gibt es keine Untersuchungen bezüglich der Anwendung des Cyclooxygenase-2-Hemmers Nimesulid in Kombination mit Bestrahlung auf Zellen des Kopf-Hals-Bereichs.Material und Methodik:Zwei Zelllinien des Kopf-Hals-Bereichs (SCC9 und SCC25) wurden mit Nimesulid (50–600 μM) behandelt und zeitversetzt oder konkomitant bestrahlt. Die Kurzzeiteffekte auf das Überleben der Zellen wurden mittels Zellzählung untersucht, Langzeiteffekte via Koloniebildungsassays. Mittels Durchflusszytometrie wurden die Auswirkungen auf den Zellzyklus 24, 48 und 72 h nach Behandlung evaluiert.Ergebnisse:Nimesulid allein war in der Lage, die Zellproliferation kurzfristig zu hemmen (Abbildungen 1, 2 und 4), allerdings ohne nachhaltigen Effekt auf die Koloniebildungsfähigkeit (Abbildungen 3 und 5). Darüber hinaus konnte weder in den Kurzzeit- (Abbildungen 2 und 4) noch in den Langzeituntersuchungen (Abbildungen 3 und 5) ein die Strahlentherapie unterstützender Effekt nachgewiesen werden.Schlussfolgerung:Nimesulid hat unterschiedliche Effekte auf die Zellproliferation und die Koloniebildungsfähigkeit und könnte die Effizienz der Strahlentherapie schwächen. Weiters bestätigt sich, dass aus Kurzzeitanalysen des Tumorwachstums nicht automatisch auf das klinisch relevante Langzeitergebnis geschlossen werden darf.

Tricalcium phosphate-based biocomposites for mandibular bone regeneration--A histological study in sheep.

The present study investigated the suitability of three different absorbable biocomposites for the repair of critical sized bone defects created at the mandibular angle of adult sheep. Each biocomposite was composed of a three-dimensional individualized polylactide scaffold, containing a tricalcium phosphate biomaterial (chronOS). Either autologous bone marrow (chOS/BoneMarrow) or coagulation factor XIII (chOS/FactorXIII) was added to the biomaterial for osteopromotion. Venous whole blood (chOS/Blood) added to the biomaterial served as a control. A total of 18 adult sheep were used for implantation studies, subdivided into three groups of six animals each. After 12 weeks of observation, the animals were sacrificed and the mandibles were retrieved for qualitative and quantitative histologic assessment within three regions of interest (transitional zone, center, and periphery) throughout the biocomposites. Successful bone regeneration was defined by the absence of scaffold deformation and the presence of new bone formation within the biocomposites. In histomorphometry, only chOS/BoneMarrow showed elevated area fractions of newly formed bone in all regions of interest (transitional zone 50.7 ± 7.5, center 31.9 ± 9.3, periphery 23.1 ± 13.5). This led to preservation of the macroscopic scaffold structure in all specimens. Zero hurdle regression confirmed this by validating the factor biocomposite as significant (p < 0.001) for regeneration success. In our experiment, chOS/BoneMarrow was the only biocomposite passing the hurdle of regeneration in all three regions of interest. In contrast, bone formation was less pronounced and uniform in chOS/FactorXIII and chOS/blood-containing specimens. In these groups, scaffolds showed obvious to significant deformation. Overall, autologous bone marrow showed the most promising results in our experimental setting. As opposed to reports in the literature, we could not confirm the suitability of coagulation factor XIII to promote bone formation, since bone formation rates were comparable only to those of the control venous blood.

Survival of patients with pathologic T0N+ oral and oropharyngeal cancer after neoadjuvant therapy and surgery: the minority report

OBJECTIVES Treatment outcome of patients with oral and oropharyngeal squamous cell carcinoma (OOSCC) achieving complete pathologic response at the primary site (ypT0) but incomplete response in loco-regional lymph nodes after preoperative chemoradiation (ypN+) is poorly described in the literature. This studys objective was to assess the survival of patients with OOSCC with ypT0N+ disease. STUDY DESIGN 176 patients with primary locally advanced OOSCC undergoing preoperative chemoradiotherapy were stratified according to the pathologic TNM classification into 6 groups: ypT0N0M0 (46%), ypT0N+M0 (10%), ypTNM I (24%), ypTNM II (4%), ypTNM III (6%), and ypTNM IV (10%). RESULTS Three-year overall survival (OS) and recurrence-free survival (RFS) rates for the ypT0N+M0 group were both 61.8% and were similar to those of the ypTNM I group (OS 62.4%; RFS rate of 59.2%). CONCLUSIONS Survival analyses showed that patients with OOSCC with ypT0N+ disease have a similar prognosis to those with pathologic TNM stage I.

Neoadjuvant radiotherapy plus radical surgery for locally advanced stage III/IV oral cancer: Analysis of prognostic factors affecting overall survival

OBJECTIVES Preoperative radiotherapy followed by surgery is an effective treatment option for solid tumors including locally advanced squamous cell cancers of the head and neck region. Histopathologic response to radiation has been shown to be associated with survival. However, the relative prognostic importance of regression grade compared to other potential biomarkers has not been established yet. MATERIALS AND METHODS One-hundred forty-four oral squamous cell carcinoma patients with stage III/IV disease were included in this analysis. Patients had received preoperative radiotherapy (RT) up to 50Gy total dose in combination with 5-Fluorouracil (5-FU)/Mitomycin C (MMC) or with Cetuximab, followed by radical surgery six to eight weeks later. Outcome data were obtained from the patients files. Survival rates were estimated by the Kaplan-Meyer method. Cox-proportional-hazard regression models were used to compare the risk of death among patients stratified according to risk factors. RESULTS Five-year overall survival (OS) was 58% in the presented collective. Regression grade 4 (HR 3.58; p<0.001) was most significantly associated with reduced survival, followed by elevated neutrophils (HR 2.22; p=0.01), the combination of elevated neutrophils plus elevated CRP (HR 2.40; p=0.01), and elevated CRP alone (HR 1.74; p=0.03). In a multivariate analysis, the regression grade remained the most influential predictor of outcome (HR 4.23; p<0.001). CONCLUSION In a comparative analysis, tumor response to pre-operative radiotherapy remains the strongest prognostic factor for treatment outcome, while elevated CRP, as well as neutrophils, were also found to be of significance.

The effect of nimesulide, a selective cyclooxygenase-2 inhibitor, on Ets-1 and Ets-2 expression in head and neck cancer cell lines.

The protooncogenes Ets‐1 and Ets‐2 are involved in carcinogenesis of different tumors. Nimesulide, a selective cyclooxygenase‐2 (COX‐2) inhibitor, has antiproliferative effects on tumor cells. The question arises whether nimesulide influences Ets‐1 and Ets‐2 synthesis in head and neck tumors.

Erratum to “Neoadjuvant radiotherapy plus radical surgery for locally advanced stage III/IV oral cancer: Analysis of prognostic factors affecting overall survival” [Oral Oncol. 60 (2016) 1–7]

University Clinic of Cranio, Maxillofacial and Oral Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria Center of Excellence of Cranio, Maxillofacial and Oral Surgery and Pediatric Dentistry, Sozialmedizinisches Zentrum Ost – Donauspital, Langobardenstraße 122, 1220 Vienna, Austria University Clinic of Radiotherapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria