Kazunobu Sueyoshi

MUC2 gene expression is found in noninvasive tumors but not in invasive tumors of the pancreas and liver: Its close relationship with prognosis of the patients☆

We have previously reported that MUC2 apomucin was highly expressed in noninvasive tumors of the pancreas (intraductal papillary tumor [IdPT]) and liver (bile duct cystadenocarcinoma [BdCC]), which show more favorable outcomes than invasive carcinomas. In contrast, MUC2 was rarely expressed in invasive carcinomas of the pancreas (invasive ductal carcinoma [IDC]) and the liver (invasive cholangiocarcinoma [ICC]). In the present study, we examined localization of MUC2 messenger RNA (MUC2 mRNA) by using a complementary DNA (cDNA) probe for the MUC2 tandem repeat for in situ hybridization (pHAM1). Localization of MUC2 apomucin was determined by using an antibody directed against MUC2 apomucin (anti-MRP) for immunohistochemistry study. Eleven IdPTs and 10 IDCs of the pancreas, and 8 BdCC and 8 ICCs of the liver were examined. Nine (82%) of 11 IdPTs showed positive expression of MUC2 mRNA in the neoplastic cells, whereas none (0%) of the IDCs showed expression of MUC2 mRNA. Six (75%) of the 8 BdCCs showed positive expression of MUC2 mRNA in the neoplastic cells, whereas none (0%) of the 8 ICCs showed expression of MUC2 mRNA. The localization of MUC2 mRNA and that of MUC2 apomucin usually coincided, although a few cases (1 IDC, 1 BdCC, and 1 ICC) showed focal expression of MUC2 apomucin despite the absence of detectable MUC2 mRNA. These results indicate that the expression of MUC2 apomucin in IdPTs and BdCCs correlates with expression of MUC2 mRNA. In both patient groups with pancreatic tumors and hepatic tumors, patients with positive MUC2 mRNA expression in the tumors showed significantly better survival than those with negative MUC2 mRNA expression in the tumors. The production of MUC2, an abundant extracellular mucin, by most IdPTs and BdCCs may be correlated with tumors that display lower levels of invasion and metastasis.

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.

Primitive neuroectodermal tumor of the transverse colonic mesentery defined by the presence of EWS-FLI1 chimeric mRNA in a Japanese woman.

EWS-FLI1 chimeric mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Based on the above findings, we finally diagnosed the tumor as PNET of the colonic mesentery. There has been no recurrence for 20 months after operation. PNET arising in the mesentery is very rare, and we distinguished PNET from other tumors by immunohistochemical examination and by demonstration of the presence of EWS-FLI1 chimeric mRNA in the tumor.

Hemangioma of the Umbilical Cord: Stenotic Change of the Umbilical Vessels

We report a rare case of an umbilical cord hemangioma diagnosed by ultrasound at 16 weeks of gestation. The umbilical cord consisted of a hemangioma nodule and pseudocysts near the placental insertion, a large gelatin-like swelling adjacent to the nodule on its fetal side, and a short normal part extending to the navel. At 17 weeks of gestation, this condition resulted in the intrauterine death of the fetus. Microscopically, there were communications between the capillary of the hemangioma and the umbilical vessels, verifying the origin of the tumor. Moreover, the umbilical vein and one of the arteries changed stenotically due to the intravascular proliferation of the hemangioma. These findings indicate the possibility of a pathological association between the umbilical cord hemangioma and fetal demise due to impaired umbilical circulation.

First-Trimester Findings Associated with Twin Reversed Arterial Perfusion Sequence

Introduction: Regarding its pathogenesis, discordant development in early gestation, as well as vascular anastomoses between twins are postulated to be required for the establishment of the twin-reversed arterial perfusion (TRAP) sequence. However, first trimester findings associated with this complication have not yet been reported. Case: A discordant monochorionic twin was revealed upon examination of a 24-year-old primigravida at 11 weeks’ gestation. Cystic masses were identified on the back of the smaller twin, later followed by the appearance of skin edema and pericardial effusion, indicating cardiac failure. Subsequently, despite diagnosis of fetal demise at 15 weeks the lower body was shown to have further developed and the heartbeats appeared again, resulting in an acardia anceps or hemicardia. No remarkable change was observed in the larger normal twin. Conclusion: This occurrence was considered consistent with the current hypothesis regarding the pathogenesis of the acardiac anomaly. First trimester discordancy in a monochorionic twin gestation is considered to represent an early manifestation of TRAP sequence.

Loss of p16/CDKN2A protein in Epstein-Barr virus-associated gastric carcinoma.

We examined the expression of p16, the CDKN2A gene product, in EBV-associated gastric carcinomas (EBV-GCs). EBV-GCs were identified by detecting EBV-encoded small RNA (EBER) using an in situ hybridization assay of paraffin-embedded tissue. Two non-EBV-GC cases for each EBV-GC case were selected, matched for age, sex, tumor location, and depth of invasion. After excluding cases without sufficient tissue samples for immunohistochemical analysis, 54 EBV-GC and 117 non-EBV-GC cases were available for the present study. The loss of p16 expression was more frequently observed in EBV-GCs (89%) than non-EBV-GC cases (32%; p < 0.001). Among non-EBV-GC cases, the loss of p16 expression was more frequent in female cases (57%) than male cases (29%) (p = 0.042). Expression of p16 was not related to the location of tumor, clinical stage of tumor, age, or prognosis of the patients. In conclusion, the present study suggests that the loss of p16-related cell cycle regulation may be associated with the development of EBV-GC.

MUC1 mucin expression in follicular dendritic cells and lymphoepithelial lesions of gastric mucosa‐associated lymphoid tissue lymphoma

Membrane‐associated mucin MUC1 is expressed in various adenocarcinoma cells and active T lymphocytes. We tried to find out whether MUC1 is expressed in gastric mucosa‐associated lymphoid tissue (MALT) lymphoma lesion. MUC1 was not expressed in infiltrating T lymphocytes; however, MUC1 was found on the cell surface of follicular dendritic cells (FDC) of germinal centers and in the epithelial cytoplasm of lymphoepithelial lesion (LEL) of the lymphoma, which were immunohistochemically detected by monoclonal antibodies DF3 and MY.1E12. MUC1 was also expressed in the FDC of control cases (gastrectomy specimen containing reactive lymphoid follicles, n = 10, MUC1/DF3, 100%; MUC1/MY.1E12, 40%), and FDC in MALT lymphomas (n = 59) showed lower MUC1 expression rates (MUC1/DF3, 32%; MUC1/MY.1E12, 0%) than the control (P < 0.001). Lymphoepithelial lesion in the low‐grade MALT lymphomas (n = 23) showed a higher MUC1/DF3 expression rate (30%) than those in the high‐grade MALT lymphomas (n = 36; 6%; P < 0.05). T lymphocytes in the surface mucosa were more frequent in MALT lymphoma (91.4 ± 80.6/unit area) than those in the control (20.0 ± 23.6) (P < 0.001). S100‐positive dendritic   cells around LEL were more frequent in the low‐grade  (19.0 ± 9.4/unit area) than  in  the high‐grade (11.7 ± 9.7) (P < 0.005). This study demonstrated MUC1 mucin expression on FDC for the first time. Mucosa‐associated lymphoid tissue lymphoma, especially low‐grade, shows immunologically active state, where FDC MUC1 expression may be suppressed by some factors released from lymphoma cells. Further study to elucidate the pathogenetic role of MUC1 in MALT lymphoma is necessary.

Anatomical distribution of HTLV-I proviral sequence in an autopsy case of HTLV-I associated myelopathy: A polymerase chain reaction study

HTLV‐I associated myelopathy (HAM) is a slowly progressive paraplegia of the lower extremities observed among HTLV‐I carriers. An autopsy of a typical HAM case in which perivascular lymphocytic infiltration was not limited to the central nervous system was examined. Spinal dorsal roots, salivary gland, lungs, liver and kidney showed non‐specific, but unusual sporadic perivascular lymphocytic infiltration, which resembled the findings in the spinal cord. To investigate the anatomical distribution of HTLV‐I provirus, the HTLV‐I proviral sequences, tax and pol, were amplified from the formalin‐fixed paraffin‐embedded tissues of the autopsy case using polymerase chain reaction (PCR). By PCR, strong HTLV‐I provirus signals were detected in the spinal cord, peripheral nerve, muscle, lungs and liver. Weak signals were detected in the medulla oblongata, optic nerve and lymph node, while the other organs, including the cerebrum, were negative. The data from this study show the specific distribution of HTLV‐I provirus in the distinct organs of a HAM patient.

Inhibin-α and synaptophysin immunoreactivity in synovial sarcoma with granular cell features

We recognized immunoreactivity for the α subset of inhibin and synaptophysin in synovial sarcomas with granular cell features. Histologic findings of 90 cases of synovial sarcoma were reviewed. Two (2.2%) of the 90 cases had granular cell features, showing sheet or nested proliferation of characteristic epithelioid cells with abundant eosinophilic and granular cytoplasm, in addition to the typical spindle cell component. The 2 cases were both female (aged 86 and 76 years). The tumors were located in the foot and the retroperitoneum and measured 3.5 and 14 cm in maximum diameter. Reverse transcriptase polymerase chain reaction analysis revealed SS18-SSX1 transcripts in both cases. SS18 gene rearrangement was detected in granular cells as well as spindle cells by chromogenic in situ hybridization. Immunohistochemistry found the granular cells to be positive for inhibin-α in both cases and for synaptophysin in 1 case, whereas spindle cells were not. Thirty-six cases (20 monophasic fibrous, 11 biphasic, and 5 poorly differentiated synovial sarcomas) were additionally examined for comparison; they showed no immunoreactivity for inhibin-α or synaptophysin. This is the first report of immunoreactivity for inhibin-α and synaptophysin in synovial sarcoma. These immunohistochemical findings might be characteristic of synovial sarcomas with granular cell features.

Production of a High-affinity Monoclonal Antibody Reactive with Folate Receptors Alpha and Beta

Folate receptors α (FRα) and β (FRβ) are two isoforms of the cell surface glycoprotein that binds folate. The expression of FRα is rare in normal cells and elevated in cancer cells. Thus, FRα-based tumor-targeted therapy has been a focus area of laboratory research and clinical trials. Recently, it was shown that a significant fraction of tumor-associated macrophages expresses FRβ and that these cells can enhance tumor growth. Although FRα and FRβ share 70% identity in their deduced amino acid sequence, a monoclonal antibody (MAb) reactive with both receptors has not been developed. A MAb that can target both FRα-expressing cancer cells and FRβ-expressing tumor-associated macrophages may provide a more potent therapeutic tool for cancer than individual anti-FRα or anti-FRβ MAbs. In this study, we developed a MAb that recognizes both FRα and FRβ (anti-FRαβ). The anti-FRαβ specifically stained trophoblasts and macrophages from human placenta, synovial macrophages from rheumatoid arthritis patient, liver macrophages from cynomolgus monkey and common marmoset, and cancer cells and tumor-associated macrophages from ovary and lung carcinomas. Surface plasmon resonance showed that the anti-FRαβ bound to soluble forms of the FRα and FRβ proteins with high affinity (KD=6.26×10(-9) M and 4.33×10(-9) M, respectively). In vitro functional analysis of the anti-FRαβ showed that this MAb mediates complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and antibody-dependent cellular phagocytosis of FRα-expressing and FRβ-expressing cell lines. The anti-FRαβ MAb is a promising therapeutic candidate for cancers in which macrophages promote tumor progression.