Oncologic Reappraisal of Bile Duct Resection for Middle-Third Cholangiocarcinoma.

BACKGROUND: Although bile duct resection (BDR) in addition to pancreaticoduodenectomy (PD) is considered a surgical approach in patients with middle-third cholangiocarcinoma (MCC), available prognostic information after BDR remains very limited. The aim of this study was to reappraise BDR from the viewpoint of surgical oncology. METHODS: Patients who underwent BDR or PD for MCC between 2001 and 2010 at 32 Japanese hospitals were included. Clinicopathological factors were retrospectively compared according to surgical procedure to identify a subset cohort who benefited most from BDR. RESULTS: During the study, 92 patients underwent BDR (n = 38) or PD (n = 54). BDR was characterized by a shorter operation time, less blood loss, less frequent complications, and lower mortality, than PD. The incidence of positive surgical margins was 26.3% versus 5.6% (P = 0.007). The survival rate after BDR was significantly worse than that after PD: 38.8% versus 54.8% at 5 years (P = 0.035), and BDR was independently associated with deteriorated survival [hazard ratio (HR), 1.76; P = 0.023] by multivariable analysis. In the BDR group, tumor length < 15 mm (HR, 3.38; P = 0.017) and ductal margin length ≥ 10 mm (HR, 2.54; P = 0.018) were independent positive prognostic factors. Stratified by these two favorable factors, the 5-year survival rate was 63.0% in patients with 1/2 factors and 6.7% in those with 0 factors (P < 0.001). CONCLUSION: In patients with MCC, BDR provided a better short-term and a worse long-term outcome than PD. However, patient selection using tumor length and ductal margin length may allow a favorable survival probability even after BDR.

Expression of CD109 in human cancer.

It was recently reported that the human CD109 gene encodes a glycosyl-phosphatidylinositol-anchored glycoprotein that is a member of the alpha(2)-macroglobulin/C3, C4, C5 family of thioester-containing proteins. In this study, we found that the expression of mouse CD109 gene was upregulated in NIH3T3 cells expressing RET tyrosine kinase with a multiple endocrine neoplasia 2B mutation. Northern blot analysis showed a high level of expression of the CD109 gene only in the testis in normal human and mouse tissues. In addition, its expression was high in some human tumor cell lines, which included squamous cell carcinoma and glioblastoma cell lines, whereas it was undetectable in neuroblastoma and small-cell lung carcinoma cell lines. When CD109 expression was examined in 33 cases of human lung cell carcinomas by quantitative RT-PCR, a significant high expression of CD109 was detected in about half of squamous cell carcinomas examined, but not in adenocarcinoma, large-cell carcinoma and small-cell carcinoma. Similarly, upregulation of CD109 was observed in nine out of 17 esophageal squamous cell carcinomas. Thus, these results suggested that CD109 might be a useful molecular target for the development of new therapeutics for malignant tumors, such as squamous cell carcinoma.

Malignant granular cell tumor of the breast: case report and literature review.

Granular cell tumors (GCTs) are uncommon soft tissue tumors that mostly occur in patients between 40 and 60 years of age and can occur at various body sites. Malignant granular cell tumors (MGCTs) comprise less than 2 % of GCTs and are mostly found on the lower extremities, especially the thighs. These tumors grow more rapidly than benign GCTs, and most importantly, they can metastasize. We describe an MGCT that presented as a right breast mass in a 79-year-old Japanese woman. Local excision was performed for the primary tumor, which was diagnosed as an atypical GCT, but 15 months later, the tumor recurred at the same site. Thereafter, right mastectomy with axillary lymph node dissection was performed. Metastatic disease was identified in 2 of 12 lymph nodes. The pathological examination revealed that the tumor had progressed to an MGCT after recurrence. Multiple liver, lung and bone metastases were revealed 4 months after the second surgery, and the patient died 34 months after the primary surgery. Our findings highlighted the difficulty in diagnosing MGCTs using histological features alone and suggested the usefulness of Ki67 values. A tumor with a high level of Ki67 should be treated as malignant, even if the tumor has few pathological features of malignancy.

CD109 expression in squamous cell carcinoma of the uterine cervix.

CD109 is a cell surface protein, a member of the alpha(2) macroglobulin/C3,C4,C5 family of thioester-containing proteins. The authors have recently reported that high expression of the CD109 gene was detected in approximately half of the examined lung and esophageal squamous cell carcinomas as well as in the testis, and that CD109 has the characteristics of a cancer-testis antigen. In the present study CD109 expression in cervical squamous cell carcinoma was compared with that in endometrial adenocarcinoma by reverse transcription polymerase chain reaction (RT-PCR). The result demonstrated that CD109 expression is significantly higher in cervical squamous cell carcinomas than in endometrial adenocarcinomas and normal cervix and endometrium. In contrast, when expression of RET finger protein (RFP) and bromodomain testis-specific (BRDT) genes, which are also known to be highly expressed in the testis, was examined, no significant difference in their expression levels was observed between squamous cell carcinomas and adenocarcinomas. These findings suggest that CD109 may become a molecular target for the development of new therapeutics for squamous cell carcinoma of various tissue origins.

Identification of a mouse cytoskeleton-associated protein, CKAP2, with microtubule-stabilizing properties.

Microtubule dynamics is an important factor in cell proliferation and one of the main targets of cancer chemotherapy. Since microtubule-associated proteins (MAPs) are known to influence microtubule stability, study of MAPs may contribute both to knowledge of cancer cell biology and to the production of new anti-cancer drugs. In this study, we identified a new mouse gene which is a homolog of human cytoskeleton-associated protein, CKAP2 gene, by differential display analysis. The level of expression of mouse CKAP2 (mCKAP2) was significantly higher in NIH3T3 cells expressing RET with a multiple endocrine neoplasia (MEN) 2A or MEN2B mutation than in parental NIH3T3 cells. Immunocytochemical analysis showed that mCKAP2 protein is localized in cytoplasm with a fibrillar appearance, and is co-localized with microtubules throughout the cell cycle. Furthermore, overexpression of mCKAP2 in cells appeared to stabilize microtubules against treatment with nocodazole, a microtubule-depolymerizing agent. In addition, levels of human CKAP2 were increased in some human tumor cell lines examined. These findings suggest that CKAP2 is a new MAP with microtubule-stabilizing properties and may represent a new molecular target for cancer chemotherapy.

Characterization of gene expression induced by RET with MEN2A or MEN2B mutation.

Germ-line point mutations of the RET gene are responsible for multiple endocrine neoplasia (MEN) type 2A and 2B that develop medullary thyroid carcinoma and pheochromocytoma. We performed a differential display analysis of gene expression using NIH 3T3 cells expressing the RET-MEN2A or RET-MEN2B mutant proteins. As a consequence, we identified 10 genes induced by both mutant proteins and eight genes repressed by them. The inducible genes include cyclin D1, cathepsins B and L, and cofilin genes that are known to be involved in cell growth, tumor progression, and invasion. In contrast, the repressed genes include type I collagen, lysyl oxidase, annexin I, and tissue inhibitor of matrix metalloproteinase 3 (TIMP3) genes that have been implicated in tumor suppression. In addition, six RET-MEN2A- and five RET-MEN2B-inducible genes were identified. Among 21 genes induced by RET-MEN2A and/or RET-MEN2B, six genes including cyclin D1, cathepsin B, cofilin, ring finger protein 11 (RNF11), integrin-alpha6, and stanniocalcin 1 (STC1) genes were also induced in TGW human neuroblastoma cells in response to glial cell line-derived neurotrophic factor stimulation. Because the STC1 gene was found to be highly induced by both RET-MEN2B and glial cell line-derived neurotrophic factor stimulation, and the expression of its product was detected in medullary thyroid carcinoma with the MEN2B mutation by immunohistochemistry, this may suggest a possible role for STC1 in the development of MEN 2B phenotype.