Stein Lybak

Normal Tissue Reactions in Mice after Combined Treatment with Metoclopramide and Ionizing Radiation

We have previously shown that metoclopramide potentiates the effect of ionizing radiation and cisplatin treatment of human squamous cell carcinomas from the head and neck region xenografted to nude mice. In the present tumor study, the dose scheduling of metoclopramide in combination with radiation was evaluated, and metoclopramide was shown to be most effective in potentiating the cytotoxic effect of radiation when administered one hour before radiation. The effect of radiation in combination with metoclopramide on normal tissue was also studied in two well-established models. Acute skin reactions to radiation exposure were studied in 129-type mice, and metoclopramide did not enhance the acute skin reaction in this in vivo model. Survival after whole body irradiation was studied in heterozygote Balb/c nu/+ mice as a measure of bone marrow toxicity. Metoclopramide was not found to affect the LD50/30 in this in vivo model. The absence of potentiation of radiation damage to normal tissue in these animal studies, makes metoclopramide an interesting possibility for future clinical evaluation.

Dose schedule evaluation of metoclopramide as a potentiator of cisplatin and carboplatin treatments of xenografted squamous cell carcinomas of the head and neck.

The potentiating effect of metoclopramide on the tumor growth inhibition of cisplatin has been studied on human squamous cell carcinomas xenografted to nude mice. In this system, the optimal time interval for intraperitoneal administration of metoclopramide was 8 h after intraperitoneal administration of cisplatin. The optimal single dose level of metoclopramide in this study was 2 mg/kg. Metoclopramide enhanced the cytotoxic effect of cisplatin at all cisplatin doses tested between 2.5 and 7.5 mg/kg body weight. Under experimental conditions that gave optimal sensitization of cisplatin-induced cytotoxicity, there was no potentiation of the cytotoxic effect with metoclopramide in combination with carboplatin. There is great similarity in the cytotoxic action of cisplatin and carboplatin, with the main difference being a much slower rate of formation of DNA crosslink formation following carboplatin exposure. Hence the data reported here support an important role for the kinetics of formation and reparability of DNA damage as part of the mechanism of metoclopramide sensitization of platinum-containing drugs.

The impact of HPV infection on survival in a geographically defined cohort of oropharynx squamous cell carcinoma (OPSCC) patients in whom surgical treatment has been one main treatment

Abstract Conclusions: We determined that 55% of the patients with oropharynx squamous cell carcinoma (OPSCC) had human papilloma virus (HPV)-positive tumors. We demonstrated that HPV-positive patients had better 5-year disease-specific survival (DSS) than the HPV-negative counterparts. This was also primarily true for cancers originating in the tonsil or base of the tongue with T3 and/or N2 tumors. Objective: Urogenital high risk (hr) HPV is an important risk factor, and probably causative agent, for OPSCC. The study investigated these factors. Methods: We identified 232 patients with OPSCC, of which 186 lesions were from the tonsil or base of the tongue region, treated in the period 1992–2008 in Western Norway. Five-year DSS was recorded for all patients. Results: In all, 124 of 226 patients had HPV-positive tumors. All except five HPV-positive patients had HPV-16-positive tumors; 69% of the patients with tonsil or base of the tongue SCC had HPV-positive tumors, whereas 14% of remaining OPSCC patients had HPV-positive tumors. Five-year DSS with HPV-positive tumor was 77% compared with 53% with an HPV-negative tumor (p < 0.001), also valid with adjustment for age, gender, and TNM stage, but primarily determined with patients with the specific tumor sites tonsils and base of the tongue with TNM stages T3 or N2.

Integrin α11 is overexpressed by tumour stroma of head and neck squamous cell carcinoma and correlates positively with alpha smooth muscle actin expression

Background Cancer‐associated fibroblasts (CAFs) were shown to be important for tumour progression in head and neck squamous cell carcinomas (HNSCCs). Their heterogeneity and lack of specific markers is increasingly recognized. Integrin α11 was recently shown to be expressed by CAFs and might serve as a specific CAF marker. Aim To investigate integrin α11 expression and its correlation with the expression of a well‐known marker of CAF, alpha smooth muscle actin (α‐SMA), in HNSCC. Methods Fresh frozen (FF) and formalin‐fixed paraffin‐embedded (FFPE) samples from healthy volunteers (n = 24), oral lichen planus (OLP) (n = 32) and HNSCC (n = 106) were collected together with clinical data after ethical approval. Immunohistochemistry to detect integrin α11 and α‐SMA was performed on FF and FFPE samples. qPCR for integrin α11 (ITGA11) and α‐SMA (ACTA2) was performed on FF samples. Data were analysed using chi‐square test and Kaplan–Meier survival analysis. Results Significantly higher levels of integrin α11 and α‐SMA at both protein and mRNA levels were found in HNSCC vs. normal controls and OLP. A strong correlation was found between integrin α11 and α‐SMA expression, and double staining showed their colocalization. Both integrin α11 and α‐SMA were detected surrounding metastatic islands. Expression of α‐SMA at tumour front but not tumour centre correlated with patient survival. Conclusion Integrin α11 was overexpressed in HNSCC stroma and colocalized with α‐SMA. Expression of α‐SMA at tumour front but not tumour centre had prognostic value for survival, pinpointing the importance of assessing tumour front when evaluating stromal molecules as prognostic biomarkers.

Radiological imaging of the neck for initial decision-making in oral squamous cell carcinomas-A questionnaire survey in the Nordic countries

Background. Fast and accurate work-up is crucial to ensure the best possible treatment and prognosis for patients with head and neck cancer. The presence or absence of neck lymph node metastases is important for the prognosis and the choice of treatment. Clinical lymph node (N)-staging is done by palpation and diagnostic imaging of the neck. We investigated the current practice of the initial radiological work-up of patients with oral squamous cell carcinomas (OSCC) in the Nordic countries. Methods. A questionnaire regarding the availability and use of guidelines and imaging modalities for radiological N-staging in OSCC was distributed to 21 Head and Neck centres in Denmark (n = 4), Finland (n = 5), Iceland (n = 1), Norway (n = 4) and Sweden (n = 7). We also asked for a description of the radiological criteria for determining the lymph nodes as clinical positive (cN+) or negative (cN0). Results. All 21 Head and Neck centres responded to the questionnaire. Denmark and Finland have national guidelines, while Norway and Sweden have local or regional guidelines. Seventeen of the 19 centres with available guidelines recommended computed tomography (CT) of the cN0 neck. The waiting time may influence the imaging modalities used. Lymph node size was the most commonly used criteria for radiological cN+, but the cut-off measures vary from 0.8 to 2.0 cm. Conclusion. Overall, CT is the most commonly recommended and used imaging modality for OSCC. Despite availability of national guidelines the type and number of radiological examinations vary between centres within a country, but the implementation of a fast-track programme may facilitate fast access to imaging. The absence of uniform criteria for determining the lymph nodes of the neck as cN+ complicates the comparison of the accuracy of the imaging modalities. Well-defined radiological strategies and criteria are needed to optimise the radiological work-up in OSCC.

The impact of HPV infection, smoking history, age and operability of the patient on disease-specific survival in a geographically defined cohort of patients with oropharyngeal squamous cell carcinoma

Abstract Conclusions: Patients with human papillomavirus (HPV)-positive tumours had better 5-year disease-specific survival (DSS) than HPV-negative patients. TNM score only predicted prognosis among HPV-negative patients. A previous history of smoking and age at diagnosis predicted DSS among HPV-positive patients whereas operability at diagnosis predicted DSS among both HPV-positive and HPV-negative patients. Objectives: HPV is a risk factor for oropharyngeal squamous cell carcinoma (OPSCC). The extent to which smoking, age and operability could play a role in HPV-positive surgically treated head and neck SCCs has not been extensively addressed previously and this study aimed to evaluate these factors. Methods: We identified 232 patients with OPSCC, of which 186 from the tonsil or base of the tongue region were treated in the period 1992–2008 in Western Norway. The 5-year DSS was recorded. Details on smoking history and whether the lesion was operable or not, as well as clinical information, were obtained retrospectively from the hospital records. Results: TNM stage predicted survival only among HPV-negative patients. A previous smoking affected prognosis only among HPV-positive patients (relative risk (RR) = 2.5; confidence interval (CI) = 1.0–6.2; p = 0.05). Increasing age of the patient had a negative effect on survival in HPV-positive patients only, especially among the oldest quartile (RR = 4.4; CI = 2.0–9.0; p < 0.001). Whether the tumour was operable or not uniquely predicted DSS both among HPV-positive (RR = 0.34; CI = 0.13–0.93; p < 0.05) and HPV-negative (RR = 0.25; CI = 0.10–0.66; p < 0.01) patients with tonsil/base of the tongue SCC.

Rapid adherence to collagen IV enriches for tumour initiating cells in oral cancer

BACKGROUND Although several approaches for identification and isolation of carcinoma cells with tumour initiating properties have been established, enrichment of a population of pure and viable tumour-initiating cells (TICs) is still problematic. This study investigated possibilities to isolate a population of cancer cells with tumour initiating properties based on their adherence properties, rather than expression of defined markers or clonogenicity. METHODS Several human cell lines derived from oral dysplasia and oral squamous cell carcinoma (OSCC), as well as primary cells derived from patients with OSCC were allowed to adhere to collagen IV-coated dishes sequentially. Rapid adherent cells (RAC), middle adherent cells (MAC) and late adherent cells (LAC) were then harvested and further investigated for their morphology, stem cell-like properties and molecular profile while grown in vitro and tongue xenotransplantation in NOD-SCID mice at serial dilutions. RESULTS RAC showed significantly higher colony forming efficiency (p<0.05), sphere forming ability, greater migration ability (p<0.05), exhibited longer G2 phase and displayed higher expression of integrin β1 and other stem-cell related molecules as compared to MAC and LAC. RAC induced tongue tumours in NOD-SCID mice with the highest incidence. These tumours were also bigger and metastasised more frequently in loco-regional lymph nodes than MAC and LAC. CONCLUSIONS These findings prove for the first time that OSCC cells with tumour initiating properties can be enriched based on their rapid adhesiveness to collagen IV. This separation procedure provides a potentially useful tool for isolating TICs in OSCC for further studies on understanding their characteristics and drug-resistant behaviour.

Ultrasound of the abdomen and total bone scintigraphy in patients with cancer of the head and neck

In this prospective study, the patients with head and neck cancer admitted to the Department of Otolaryngology and Head and Neck Surgery, Haukeland University Hospital, underwent examination with ultrasound of the abdomen (112 patients) and total bone scintigraphy (118 patients) in the primary staging of the disease and before the start of treatment. In only one patient did we find metastases of head and neck cancer in the liver by these additional investigations, and one patient was found to have bone metastases. No second primary cancers were found by these extra examinations. One patient was found to have an asymptomatic aorta aneurysm and was in need of urgent surgical treatment. Based on these findings, we nowadays only use ultrasound of the abdomen and total bone scintigraphy as part of the general examination of new head and neck patients in selected cases.