Takashi Masui

Intraoperative diagnosis of cancer metastasis in sentinel lymph node of oral cancer patients

Sentinel lymph node (SLN) biopsy in the head and neck region is attracting attention. If intraoperative frozen section and/or cytology of SLN is available, one can select an appropriate patient who must undergo neck dissection in a one-stage procedure. We began intraoperative diagnosis of SLN biopsy in patients who underwent oral cancer surgery in 2003. From August 2003 to December 2006, 44 previously untreated patients were accumulated. All patients underwent SLN biopsy prior to the resection of primary cancer. Intraoperative diagnosis of SLN biopsy was performed by multislice frozen section analysis. Patients with positive SLN underwent immediate neck dissection in the same session. Imprint cytology specimen was prepared at the same time. The results of frozen section analysis and imprint cytology were compared with postoperative pathologic diagnosis of permanent specimens. The sensitivity, specificity, overall accuracy, positive and negative predictive value of intraoperative multislice frozen section analysis in lymph node basis were 90.9%, 100%, 99.1%, 100% and 99.0%, respectively. On the other hand, the indexes of imprint cytology were 27.3%, 99.0%, 92.0%, 75.0% and 92.6%, respectively. All indexes of intraoperative frozen section analysis were superior to imprint cytology. In our experience, multislice frozen section analysis surpasses imprint cytology in intraoperative diagnosis of SLN biopsy.

Snail-induced EMT promotes cancer stem cell-like properties in head and neck cancer cells.

Epithelial-mesenchymal transition (EMT) is a key process involved in the invasion and metastasis of cancer cells. Furthermore, EMT can induce a cancer stem cell (CSC)-like phenotype in a number of tumor types. We demonstrated that Snail is one of the master regulators that promotes EMT and mediates cancer cell migration and invasion in many types of malignancies including head and neck squamous cell carcinoma (HNSCC). In the present study, we investigated the role of Snail in inducing and maintaining CSC-like properties through EMT in HNSCC. We established HNSCC cell lines transfected with Snail. Stem cell markers were evaluated with real-time RT-PCR and western blot analysis. CSC properties were assessed using sphere formation and WST-8 assays as well as chemosensitivity and chick chorioallantoic membrane in vivo invasion assays. Introduction of Snail induced EMT properties in HNSCC cells. Moreover, Snail-induced EMT maintained the CSC-like phenotype, and enhanced sphere formation capability, chemoresistance and invasive ability. These data suggest that Snail could be one of the critical molecular targets for the development of therapeutic strategies for HNSCC.

Heparin-binding EGF-like growth factor enhances the activity of invasion and metastasis in thyroid cancer cells

Thyroid cancer sometimes contains poorly differentiated components, which have the potential of invasion and metastasis. We evaluated the possible roles of heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor (EGF) family, in cell growth and invasion of thyroid cancer cells, and demonstrated that HB-EGF is not only a potent mitogen but also a chemotactic factor in the thyroid cancer cells 8305C and SW579. The HB-EGF-mediated chemotaxis was inhibited by neutralizing antibody against the EGF receptor (EGFR/HER1/ErbB1) or tyrphostin AG1478, a specific inhibitor of the EGFR tyrosine kinase. The HB-EGF mRNA and protein expression was also analyzed using RT-PCR and immunofluorescence methods, respectively. In addition, in clinical immunohistochemical study, increased expression of HB-EGF and its receptors, HER1 and EGFR4 (HER4/ErbB4), was observed in thyroid carcinoma cells. Our findings suggest that HB-EGF acts as a potent paracrine and/or autocrine chemotactic factor as well as a mitogen that mediates HER1 and/or HER4 in the invasion and metastasis of thyroid carcinoma cells, including poorly differentiated papillary carcinomas or undifferentiated/anaplastic carcinomas. These data may aid in the development of novel therapeutic strategies for thyroid cancer.

Low-intensity ultrasound enhances the anticancer activity of cetuximab in human head and neck cancer cells

The potential clinical use of ultrasound in inducing cell apoptosis and enhancing the effects of anticancer drugs in the treatment of cancers has previously been investigated. In this study, the combined effects of low-intensity ultrasound (LIU) and cetuximab, an anti-epidermal growth factor receptor (EGFR) antibody, on cell killing and induction of apoptosis in HSC-3 and HSC-4 head and neck cancer cells, and its mechanisms were investigated. Experiments were divided into 4 groups: non-treated (CNTRL), cetuximab-treated (CETU), ultrasound-treated (UST) and the combination of cetuximab and US-treated (COMB). Cell viability was assessed by trypan blue staining assay and induction of apoptosis was detected by fluorescein isothiocyanate (FITC)-Annexin V and propidium iodide (PI) staining assay at 24 h after cetuximab and/or US treatment. To elucidate the effect of cetuximab and US on EGFR signaling and apoptosis in head and neck cancer cells after the treatments, the expression of EGFR, phospho-EGFR, and the activation of caspase-3 were evaluated with western blotting. More cell killing features were evident in the COMB group in HSC-3 and HSC-4 cells compared with the other groups. No differences in EGFR expression among the CETU, UST and COMB groups was observed, while the expression of phospho-EGFR in the CETU group was downregulated compared with that in the CNTRL group. Phospho-EGFR expression was much more downregulated in the COMB group compared with that in the other groups. In addition, the activation of caspase-3 in the UST group was upregulated compared with that in the CNTRL group. Caspase-3 activation was much more upregulated in the COMB group than that in the other groups. These data indicated that LIU was able to enhance the anticancer effect of cetuximab in HSC-3 and HSC-4 head and neck cancer cells.

Impact of positron emission tomography with the use of fluorodeoxyglucose on response to induction chemotherapy in patients with oropharyngeal and hypopharyngeal squamous cell carcinoma.

Abstract Conclusion: Maximum standardized uptake values (SUVmax) have prognostic value for induction chemotherapy (ICT) response and survival in oropharyngeal and hypopharyngeal squamous cell carcinoma (OHSCC) patients. Pretreatment positron emission tomography with the use of fluorodeoxyglucose (18F-FDG PET) may be an aid in deciding the treatment strategy in OHSCC patients. Objectives: We investigated the association between pretreatment 18F-FDG PET and response to ICT and survival in OHSCC patients. Methods: We conducted a retrospective cohort study of 58 OHSCC patients treated at Aichi Cancer Center Hospital. The predictive impact of SUVmax of the primary tumor site was evaluated using statistical multivariate proportional hazard models. Results: Thirty-one cases (53%) were located in the oropharynx and 27 (47%) in the hypopharynx. Median SUVmax was 11.6 (range 3.2–23.5), and was significantly higher in the 8 patients with less than stable disease than in the 50 with more than partial response (median SUVmax, 17.3 vs 11.1; p = 0.002). In multivariate analysis, hazard ratios for the medium and high SUVmax groups relative to the low group were 3.07 (95% confidence interval, 0.62–15.29; p = 0.170) and 4.71 (0.97–22.89; p = 0.055), respectively, and the dose-response relationship was statistically significant (p trend = 0.047). A similar tendency was observed on subclassification by oropharynx and hypopharynx.

Abstract 3054: Snail-induced epithelial-mesenchymal transition generates the properties of cancer stem cells in head and neck cancer cells

Head and neck squamous cell carcinoma (HNSCC) is known to its rapid clinical progression and poor prognosis. Notably, regional and distant metastases in HNSCC correspond to an extremely poor prognosis with limited treatment options. The treatment resistance and tumor recurrence are important clinical problems in the management of HNSCC. Epithelial-mesenchymal transition (EMT) is a key process in successful execution of many steps such as invasion and metastasis for cancer cells. Snail is one of master regulators that promote EMT in many types of malignancies including HNSCC. Recently, it has been reported that Snail-induced EMT could induce cancer stem cell (CSC)-like phenotype in a number of tumor types. Herein, we investigated the role of Snail in inducing EMT properties and CSC-like phenotype in HNSCC. We constructed HNSCC cell lines transfected with Snail. E-cadherin was analyzed using western blotting and immunofluorescence staining. Cell migration and invasion were assessed using wound healing assay and modified Boyden chamber assay, respectively. CSC markers of HNSCC, CD44 and aldehyde dehydrogenase 1 (ALDH1), were also evaluated with western blotting, and chemosensitivity was assessed with WST-8 assay. Introduction of Snail induced EMT properties in HNSCC cells and enhanced cell migration and invasion. Moreover, Snail-induced EMT gained CSC-like phenotype and was associated with increased chemoresistance. These results suggest that Snail can be one of the attractive targets for the development of therapeutic strategies in HNSCC. Citation Format: Ichiro Ota, Takashi Masui, Shinji Mikami, Toshiaki Yamanaka, Hiroshi Hosoi. Snail-induced epithelial-mesenchymal transition generates the properties of cancer stem cells in head and neck cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3054. doi:10.1158/1538-7445.AM2014-3054

Four Case Series of Nasal NK/T Cell Lymphoma Treated with Chemoradiotherapy

Nasal NK/T-cell lymphoma is a rare subtype of lymphoma with a significantly worse prognosis than other subtypes, and also tends to be commonly found in people of East Asian, Mexican, or South American descent.Patient 1 was treated with chemotherapy using the CHOP regimen after radiotherapy. At 14 months after the end of treatment the patient demonstrated recurrence to primary site and the jejunum. He is presently alive with this disease at 30 months after the end of treatment. Patient 2 was treated with chemotherapy using the CHOP regimen after radiotherapy, but this schedule resulted in only a partial response to the disease. As a result, chemotherapy was also performed using the DeVIC regimen with 3 cycles. Patient 2 is still alive and has been free of any relapse for 48 months. Patient 3 was treated with concurrent chemoradiotherapy using 56Gy irradiation with the DeVIC regimen. Patient 3 is still alive and has been free of relapse for 12 months. Because of this chemoradiotherapeutic regimen, patient 3 suffered severe mucositis and pancytopenia, and as a result he could not complete chemotherapy, which normally consists of 3 cycles. Patient 4 was treated with concurrent chemoradiotherapy using 56Gy irradiation with the DeVIC regimen. Patient 4 is still alive and has been free of relapse for 6 months. In patient 4, we used 2/3-dose chemotherapy in comparison to the patient 3 dose. As a result, the chemoradiotherapy in patient 4 did not cause any severe side effects. Concurrent chemoradiotherapy using the DeVIC regimen may therefore be effective for the treatment of NK/T-cell lymphoma.