Kazumasa Sugihara

Tumor lymphangiogenesis correlates with lymph node metastasis and clinicopathologic parameters in oral squamous cell carcinoma

Lymphatic vessel density (LVD) and microvessel density (MVD) are important parameters for assessing the malignant potential of tumors and patient survival. In this report, the authors defined LVD as the density of D2‐40‐positive lymphatic vessels and MVD as the density of CD105‐positive microvessels per unit area of tissue. It was reported previously that vascular endothelial growth factor C (VEGF‐C) is a major modulator of LVD and MVD. The objectives of this study were to clarify the clinical and prognostic significance of both LVD and MVD in oral squamous cell carcinoma (OSCC) and to elucidate the lymphangiogenic and angiogenic activities of VEGF‐C in cancer tissues.

Mucin expression in pleomorphic adenoma of salivary gland: a potential role for MUC1 as a marker to predict recurrence

Background: Pleomorphic adenoma of the salivary gland (PA) is essentially a benign neoplasm. However, patients with recurrent PA are difficult to manage. There are rare reports on useful immunohistochemical markers to detect a high risk of recurrence when the primary lesions are resected. Aims: To find a new marker to predict the recurrence of PA. Methods: Primary lesions of PA were collected from nine patients showing subsequent recurrence and from 40 patients without recurrence during at least 10 years of follow up of the disease. Paraffin wax embedded tumour samples of the two groups were examined for the expression profiles of MUC1 (differentially glycosylated forms), MUC2, MUC4, MUC5AC, and MUC6 using immunohistochemistry. Several clinicopathological factors were also examined. Results: In univariate analysis of the factors examined, MUC1/DF3 high expression (more than 30% of the neoplastic cells stained) in the primary lesions was seen more frequently in patients with recurrence (four of nine) than in those without recurrence (three of 40; p  =  0.011). Larger tumour size (more than 3.0 cm) of the primary PA was also a significant (p  =  0.035) risk factor for the recurrence of PA. In multivariate analysis, only high expression of MUC1/DF3 was found to be a significant independent risk factor for the recurrence of PA (p  =  0.021). Conclusions: Expression of MUC1/DF3 in PA is a useful marker to predict its recurrence. Those patients with PA showing positive MUC1/DF3 expression should be followed up carefully.

Aberrant DNA methylation of tumor-related genes in oral rinse: a noninvasive method for detection of oral squamous cell carcinoma.

The early detection of oral squamous cell carcinoma (OSCC) is important, and a screening test with high sensitivity and specificity is urgently needed. Therefore, in this study, the authors investigated the methylation status of tumor‐related genes with the objective of establishing a noninvasive method for the detection of OSCC.

Human papillomavirus in upper digestive tract tumors from three countries

AIM To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined. Comparison of p53 and p16(INK4a) expression in HPV-positive and HPV-negative cases was also made. RESULTS HPV16 was found in 39 (55%) oral carcinomas (OCs) and 24 (14%) esophageal carcinomas (ECs). This site-specific difference in HPV detection between OCs and ECs was statistically significant (P < 0.001). There was a significant difference in the geographical distribution of HPV16-E6 variants. Multiple infections of different HPV types were found in 13 ECs, but multiple infections were not found in OCs. This difference was statistically significant (P = 0.001). The geometric means (95% confidence interval) of HPV16 viral load in OCs and ECs were 0.06 (0.02-0.18) and 0.12 (0.05-0.27) copies per cell, respectively. The expression of p16(INK4a) proteins was increased by the presence of HPV in ECs (53% and 33% in HPV-positive and -negative ECs, respectively; P = 0.036), and the high-risk type of the HPV genome was not detected in surrounding normal esophageal mucosa of HPV-positive ECs. CONCLUSION Based on our results, we cannot deny the possibility of HPV16 involvement in the carcinogenesis of the esophagus.

Histochemical, immunohistochemical, and ultrastructural studies of gingival fibromatosis: a case report.

 Gingival fibromatosis is a rare disease characterized by enlargement of the gingiva. The purpose of this study was to analyze a case of idiopathic gingival fibromatosis, using histochemical and immunohistochemical staining and transmission electron microscopy. The patient was a 39-year-old Japanese man, in whom the gingiva was enlarged throughout the entire mandible and maxilla. Specimens of gingival fibromatosis exhibited epithelial hyperplasia and increased amounts of collagen fiber bundles in the connective tissue light-microscopically. Well-developed collagen bundles were strongly stained with Azan and Masson trichrome staining. Immunohistochemically, the gingival connective tissue was specifically stained by type I collagen and vimentin antibodies. Ultrastructurally, the lesion consisted of fibroblasts and mature collagen fibers running in all directions. No myofibroblasts were detected histochemically, immunohistochemically, or ultrastructurally. These findings suggested that this disease may be the result of an increase in collagen synthesis by the fibroblasts and/or that it may be associated with one of the findings of histologic heterogeneity.

MUC4: a novel prognostic factor of oral squamous cell carcinoma.

MUC4 mucin is now known to be expressed in various normal and cancer tissues. We have previously reported that MUC4 expression is a novel prognostic factor in several malignant tumors; however, it has not been investigated in oral squamous cell carcinoma (OSCC). The aim of our study is to evaluate the prognostic significance of MUC4 expression in OSCC. We examined the expression profile of MUC4 in OSCC tissues from 150 patients using immunohistochemistry. Its prognostic significance in OSCC was statistically analyzed. MUC4 was expressed in 61 of the 150 patients with OSCC. MUC4 expression was significantly correlated with higher T classification (p = 0.0004), positive nodal metastasis (p = 0.049), advanced tumor stage (p = 0.002), diffuse invasion of cancer cells (p = 0.004) and patients death (p = 0.004) in OSCC. Multivariate analysis showed that MUC4 expression (p = 0.011), tumor location (p = 0.032) and diffuse invasion (p = 0.009) were statistically significant risk factors. Backward stepwise multivariate analysis demonstrated MUC4 expression (p = 0.0015) and diffuse invasion (p = 0.018) to be statistically significant independent risk factors of poor survival in OSCC. The disease‐free and overall survival of patients with MUC4 expression was significantly worse than those without MUC4 expression (p < 0.0001 and p = 0.0001). In addition, the MUC4 expression was a significant risk factor for local recurrence and subsequent nodal metastasis in OSCC (p = 0.017 and p = 0.0001). We first report MUC4 overexpression is an independent factor for poor prognosis of patients with OSCC; therefore, patients with OSCC showing positive MUC4 expression should be followed up carefully.

Higher osteoclastic demineralization and highly mineralized cement lines with osteocalcin deposition in a mandibular cortical bone of autosomal dominant osteopetrosis type II: ultrastructural and undecalcified histological investigations.

In this study we report on histological and ultrastructural investigations of the mandibular cortical bone in a case of autosomal dominant osteopetrosis type II complicated by mandibular osteomyelitis. Histologically, there was a marked increase in the number and size of osteoclasts on the inner bone surface. An undecalcified preparation showed a pair of deeply stained (highly demineralized) and stain-phobic (highly mineralized) layers on the bone surface just beneath the osteoclasts. The layers were incorporated into the bone matrix during the remodeling process as thickened cement lines. A contact microradiogram of the cortical bone revealed highly mineralized layers at the cement lines, which were closely correlated with immunohistochemical evidence of deposition of osteocalcin at the thickened cement lines. Ultrastructural examination showed that the osteoclasts had a typical clear zone, but they were deficient in ruffled border formation and had numerous lysosomal vacuoles containing dense substances. An electron-dense amorphous material layer was present on the bone surface just beneath the osteoclasts as well as at the cement lines. The layer was partly composed of a short fibrillar material, and it partially revealed the lamellar structure. Consequently, an osteoclastic malfunction might be primarily involved in the process of bone matrix resorption rather than demineralization, resulting in higher demineralization and abnormal material deposition on the bone surface and at the cement lines. Furthermore, evidence of active osteoclastic bone resorption with a brush border formation at the bone involved in the inflammatory lesion in this case suggests that the osteoclastic malfunction is influenced and recovered by a microenvironment such as inflammatory cytokines.

Chondroma and osteochondroma of the tongue

The first case of two separate tumors of the tongue, one cartilaginous and the other osteocartilaginous, is reported. The cartilaginous matrix of these two tumors contained elastic fibers and type II collagen. The histogenesis of these tumors is discussed.

Effect of a chimeric anti-ganglioside GM2 antibody on ganglioside GM2-expressing human solid tumors in vivo

Ganglioside GM2 is expressed on the surface of neuroblastoma and glioblastoma cells, and may also be detected on lung cancer cells. We reported previously that anti‐ganglioside GM2 antibody exhibited strong in vitro anti‐tumor activity against adriamycin‐resistant cancer cells, which overexpressed ganglioside GM2. In the present study, we examined the in vivo anti‐tumor effect of the chimeric anti‐ganglioside GM2 antibody, KM966, against human lung and breast carcinoma cells, SBC‐3 and MCF‐7, and respective adriamycin‐resistant clones, SBC‐3/ADM and AdrR MCF‐7 in BALB/c nu/nu mice. Ratios of tumor volume (T/C) between KM966‐treated group and control group were 0.01 for SBC‐3, 0.00 for SBC‐3/ADM, 0.85 for MCF‐7 and 0.34 for AdrR MCF‐7 cells, respectively. Nude mice, which were pretreated with anti‐asialo GM1 antibody to remove natural killer cells, were transplanted with 4 × 107 of SBC‐3 and SBC‐3/ADM subcutaneously. Seven days later, when tumors had grown to a diameter of over 8 mm, mice began to receive intravenous treatment of 120 μg/mouse KM966 daily. Fourteen daily treatments induced regression to less than 4‐mm diameter in 4/5 SBC‐3 tumors and 5/5 of SBC‐3/ADM tumors. All SBC‐3/ADM tumors disappeared completely, suggesting that KM966 exerts a strong in vivo anti‐tumor effect on ganglioside GM2‐expressing cancer cells. In KM966‐treated mice, the surface of the tumor cells stained positive with anti‐human IgG. In addition, numerous leukocytes had infiltrated into the tumor mass. Antibody‐dependent cell‐mediated cytotoxicity (ADCC) of KM966 against tumor cells was examined in vitro by 51Cr‐release assay and revealed that KM966 induces ADCC activity against ganglioside GM2‐expressing tumors. Our results suggest that immunotherapy using KM966 may be useful for the treatment of ganglioside GM2‐expressing solid tumors. Int. J. Cancer 82:759–764, 1999.

Primary neck management among patients with cancer of the oral cavity without clinical nodal metastases: A decision and sensitivity analysis.

A standardized neck management strategy for oral cancer patients without clinical nodal metastases remains to be established. Consequently, a decision and sensitivity analysis of two neck management protocols, involving either prophylactic neck dissection or careful observation, was conducted using the Oral Cancer Registry of Kyushu, Japan.