Nobuhiro Hanai

MECT1-MAML2 Fusion Transcript Defines a Favorable Subset of Mucoepidermoid Carcinoma

Purpose: Mucoepidermoid carcinoma is the most common primary malignancy of the salivary gland. Mucoepidermoid carcinoma translocated gene 1-mastermind-like gene family (MECT1-MAML2) gene fusion was identified from a recurring t(11;19)(q21;p13) translocation, which is often the sole cytogenetic alteration in this disease. This fusion transcript has been frequently detected in mucoepidermoid carcinoma and shown to be involved in the transformation of epithelial cells. However, its clinicopathologic significance remains unclear. Experimental Design: Seventy-one cases of mucoepidermoid carcinoma and 51 cases of nonmucoepidermoid carcinoma salivary gland tumors (including 26 Warthin tumor cases) were retrospectively analyzed. RNA was extracted from archival materials: histologic paraffin specimens in all cases and cytologic specimens in 10 mucoepidermoid carcinoma cases. The MECT1-MAML2 fusion transcript was detected by a reverse transcription-PCR assay, which can be applied to both histologic and cytologic specimens. The presence of the fusion transcript was correlated with relevant clinicopathologic and survival data of the mucoepidermoid carcinoma patients. Results: The MECT1-MAML2 fusion transcript was detected in 27 of the 71 (38%) mucoepidermoid carcinoma cases but not in any case of nonmucoepidermoid carcinoma tumors. The reverse transcription-PCR results showed no difference between histologic and cytologic specimens. Detection of the MECT1-MAML2 fusion transcript was associated with a less advanced clinical stage and a low-grade tumor histology. The presence of the transcript was associated with longer disease-free and overall survivals on univariate analysis and emerged as an independent prognostic factor for longer overall survival on multivariate analysis. Conclusions: The MECT1-MAML2 fusion transcript may be specific to mucoepidermoid carcinoma and associated with a distinct mucoepidermoid carcinoma subset that exhibits favorable clinicopathologic features and an indolent clinical course.

Biochemical and cell biological characterization of a mammalian septin, Sept11

Septins are a family of conserved cytoskeletal GTPases implicated in a variety of cellular functions such as cytokinesis and vesicle trafficking. Here, we report identification of an yet uncharacterized septin, Sept11, in septin complexes purified from porcine brain. The transcripts were detected in all tested tissues except leukocytes. A Sept11 mutant with apparently reduced GTPase activity did not form filaments in the transient expression system using COS7 cells. By Western blot analysis using a specific antibody, Sept11 was detected in various cell lines as well as brain tissues. Septin complexes immunoisolated from porcine brain with anti‐Sept9 and anti‐Sept11 antibodies were found to contain different Sept9 isoforms based on SDS–PAGE analyses followed by silver‐staining and Western blotting. Immunofluorescent study revealed cell type‐dependent intracellular localization of the protein; Sept11 was colocalized dominantly with microtubules and actin stress fibers in HMEC cells and REF52 cells, respectively, and their filamentous distribution was dependent on the cytoskeleton structures with which the protein is colocalized. Sept11 partially colocalized with stress fibers and microtubules in HeLa cells.

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.

Impact of smoking status on clinical outcome in oral cavity cancer patients

The association between smoking status and survival in oral cavity squamous cell carcinoma (OSCC) patients remains unclear. Therefore, we evaluated the association between smoking status before treatment and clinical outcome in OSCC patients. We conducted a retrospective cohort study of 222 OSCC patients who were treated at Aichi Cancer Center in Japan. Of these, 82 patients (36.9%) were non-smokers, 65 (29.3%) were light smokers (pack-years smoking (PY) <30), 54 (24.3%) were moderate smokers (30≤PY<60), and 21 (9.5%) were heavy smokers (60≤PY). The survival impact of pre-treatment smoking status was evaluated using multivariate proportional hazard models. Five-year overall survival for non-, light, moderate, and heavy smokers was 72.9% (95% confidence interval CI): (61.4-81.5), 85.5% (74.0-92.2), 59.9% (44.3-72.4) and 69.0% (42.8-85.0). Adjusted hazard ratios (HRs) for moderate and heavy smokers in comparison with light smokers were 2.44 (1.07-5.57, P=0.034) and 2.66 (0.97-7.33, P=0.058) and the dose-response relationship among smokers was statistically significance (P(trend)=0.024). In addition, adjusted HR for non-smokers relative to light smokers was 2.27 (0.84-6.15, P=0.108). We observed a suggestive heterogeneity in the impact of smoking status by treatment method (P for heterogeneity=0.069). Effect of smoking was evident only among the chemoradiotherapy or radiotherapy group. In this study, we found the significant positive dose-response relationship among smokers on clinical outcome in OSCC patients and that non-smokers were worse prognosis than light smokers. In addition, this effect might differ by treatment method.

Follow-up after intraoperative sentinel node biopsy of N0 neck oral cancer patients

The objective of the study was to evaluate the validity of sentinel node (SN) biopsy in early oral cancer patients focusing on the accuracy of intraoperative diagnoses of SN status, recurrences in follow-up and impact on patient survival. Previously untreated N0 oral cancer patients were candidates for the study. Using a radioisotope method, an intraoperative SN biopsy was performed. Patients with a positive frozen section of SN underwent immediate neck dissection as a single-stage procedure; they were followed in our outpatient clinic. Forty-five cT1-2N0 patients with squamous cell carcinoma were analyzed. There were seven patients with positive SN, five of whom were detected by intraoperative frozen section analysis. The sensitivity, specificity and accuracy of the intraoperative frozen section analysis of SN were 71.4, 100 and 95.6%, respectively. There were 13 recurrences in the course of all patients treated. Those with positive SN showed a tendency toward recurrence. Three patients with negative SN suffered from delayed ipsilateral neck recurrence. These were considered false negatives at a rate of 7.9%. The 5-year overall survival rate of all patients was 91.1%. SN-positive patient survival was significantly poorer than that of SN-negative patients. Positive SN had a negative impact on the survival. SN biopsy was shown to be a valuable method for determining the neck status of early oral cancer patients. The concordance rate of intraoperative multislice frozen section analysis of SN and patient neck status at the time of operation was 95.6%. SN-positive patients exhibited a tendency toward cancer recurrence. There were three cases of false negatives not conforming to the SN concept and their rate was 7.9%. Positive SN had a negative impact on patient survival.

Prediction of Chemosensitivity Using Multigene Analysis in Head and Neck Squamous Cell Carcinoma

Aims: The main purpose of the current study was to find predictive biomarkers that can be routinely used for the response to chemotherapy in head and neck squamous cell carcinoma (HNSCC). Methods: From this standpoint, we selected the histoculture drug response assay (HDRA) to assess in vitro chemosensitivity, and real-time reverse transcription polymerase chain reaction to investigate the gene expression profile of individual tumors as available predictive biomarkers. Using both surgery and biopsy specimens, we analyzed their gene expression profiles using the 18 markers that we thought were likely predictors of the response to anti-cancer agents. Results: Statistically significant associations were found between 5-fluorouracil (5-FU) sensitivity in HDRA and HER-2 mRNA expression level (p = 0.0030). Moreover, HER-2 expression was significantly associated with cisplatin sensitivity (p = 0.0089). Cisplatin sensitivity in HDRA was also demonstrated to have a significant association with epidermal growth factor receptor (EGFR) expression in which the group with cisplatin resistance tended to have a higher expression level than the sensitive group (p = 0.0385). Conclusion: HER-2 and EGFR may be possible reliable predictive biomarkers for anti-cancer therapy, and might help in the decision-making process for individual patients with HNSCC.

Survival impact of pulmonary metastasectomy for patients with head and neck cancer.

The purpose of this study was to evaluate the survival impact and prognostic factors of pulmonary metastasectomy in patients with pulmonary metastasis from head and neck cancer.

MYB, MYBL1, MYBL2 and NFIB gene alterations and MYC overexpression in salivary gland adenoid cystic carcinoma

Adenoid cystic carcinoma (AdCC) is one of the most common salivary gland malignancies and the long‐term prognosis is poor. In this study, we examined alterations of AdCC‐associated genes, MYB, MYBL1, MYBL2 and NFIB, and their target molecules, including MYC. The results were correlated to clinicopathological profile of the patients.

Inverse association between yoghurt intake and upper aerodigestive tract cancer risk in a Japanese population.

Although the combination of tobacco smoking and alcohol drinking account for approximately 80% of upper aerodigestive tract (UADT) cancer risk, the role of dietary factors, including dairy products, in the risk of these cancers remains controversial. We aimed to evaluate the association between dairy product intake and UADT cancer risk in a Japanese population. We conducted a case–control study in 959 patients with UADT cancer and 2877 sex- and age-matched noncancer control subjects who visited the Aichi Cancer Center in Nagoya, Japan. Data on lifestyle factors, including diet, were obtained by self-administered questionnaire. Associations were assessed by multivariate logistic regression models that considered potential confounders. We found a significant inverse association between yoghurt intake and UADT cancer risk with multivariate-adjusted odds ratios and 95% confidence intervals for <1 time/week, ≥1 time/week and <1 time/day, and ≥1 time/day consumption of yoghurt of 0.70 (95% confidence interval: 0.54–0.91), 0.67 (0.54–0.84), and 0.73 (0.55–0.95) relative to nonconsumers (Ptrend=0.005). When stratified by primary tumor site, this association was significant among patients with hypopharyngeal, laryngeal, and esophageal cancer. However, we saw no significant association between milk or butter intake and UADT cancer risk. In this study, we found that a high intake of yoghurt may lower the risk of developing UADT cancer in a Japanese population. Further investigation of this association is warranted.

Prognostic factors and outcomes for salvage surgery in patients with recurrent squamous cell carcinoma of the tongue

Recurrence rates of oral cancer following primary treatment have been reported in the range of 25–48%. However, salvage therapy remains a critical challenge to improving outcomes. Here, we investigated prognostic factors and outcomes for salvage surgery in patients with recurrent oral tongue squamous cell carcinoma (OTSCC).