Yoshimitsu Minari

Comparative significance of p53 and WAF/1-p21 expression on the efficacy of adjuvant chemotherapy for resectable invasive ductal carcinoma of the pancreas

p53 tumor-suppressor gene has a dual role as a trigger of apoptosis and as an initiator of DNA repair. The cyclin-dependent kinase inhibitor WAF/1-p21 is induced by wild-type p53 and has been implicated as a downstream mediator of the growth-suppressing and apoptosis-promoting function of wild-type p53, suggesting an impact on the effectiveness of chemotherapy. This study was designed to assess the significance of p53 and WAF/1-p21 expression in the prognosis of patients and the efficacy of adjuvant chemotherapy for resectable invasive ductal carcinoma (IDC) of the pancreas. A total of 58 patients with primary IDC of the pancreas underwent pancreatectomy between 1982 and 1996: 28 patients underwent surgery alone, and 30 patients received postsurgical adjuvant chemotherapy. p53 and WAF/1-p21 were stained immunohistochemically with anti-p53 monoclonal antibody (mAb) and anti-WAF/1-p21 mAb. p53 was positively expressed in 29 (50%) of 58 primary lesions, and p21 was expressed in 24 (41%) lesions; however, p21 expression did not necessarily correlate with p53 expression. The survival curve of the patients with p53(+) IDC was significantly lower than that of those with p53(-) IDC, and p21(+) patients showed a higher survival curve than did p21(-) patients, but this difference was not statistically significant. When p53 and p21 expression were analyzed in combination, the patients with p53(+)p21(-) IDC were found to have a significantly poorer prognosis than others. On the other hand, the survival curve of the adjuvant chemotherapy group was also higher than that of the surgery-alone group, but this difference was not significant. In a multivariate analysis, p21 expression was a significantly low risk factor for death due to IDC overall, and adjuvant chemotherapy was found to decrease the risk of death from IDC in p53(+) patients. Evaluation of expression of p53 and WAF/1-p21 may be beneficial in the prediction of the patients prognosis as well as prediction of the effects of adjuvant chemotherapy in pancreatic cancer patients.

A quinolinone derivative, vesnarinone (OPC-8212), significantly inhibits the in vitro and in vivo growth of human pancreatic cancer cell lines.

A quinolinone derivative, vesnarinone, has been used as a cardiotonic agent. Previous studies have demonstrated that vesnarinone has potent antitumor activity. The present study was designed to assess the antitumor effects of vesnarinone on human pancreatic cancer cell lines in vitro and in vivo. The in vitro effects of vesnarinone on the human pancreatic cancer cell lines (PANC-1, MIA PaCa-2 and BxPC-3) were assessed by the MTT assay, the Trypan blue dye exclusion test and the Matrigel invasion chamber assay. The inhibition of in vivo tumor growth was evaluated on two human pancreatic cancer xenografts (BxPC-3 and SPa-1) transplanted s.c. into nude mice. The dose of vesnarinone for 50% inhibition of cell growth in a 7 day culture ranged between 10 and 20 µg/ml as verified by the Trypan blue dye exclusion test. The dose for 50% cytotoxicity after a 3 day culture in the MTT assay was 32 (µg/ml for PANC-1 and 30 µg/ml for BxPC- 3, but 50% cytotoxicity for MIA PaCa-2 was not achieved by the maximal dose of vesnarinone (50 µg/ml). Nomalsky optic microscopy and acridine orange staining demonstrated the vacuolization and crater-like changes in the cell nucleus after vesnarinone treatment. Moreover, staining of an apoptosis marker (Ley protein) and nick end-labeling increased. Vesnarinone also inhibited cancer invasion in the Matrigel invasion chamber assay. In vivo, BxPC-3 and SPa-1 were s.c. transplanted into the nude mice, and vesnarinone (5 or 50 mg/kg) was daily administered orally for 21 days. In both lines, vesnarinone at 50 mg/kg achieved significant inhibition. The present study suggests that vesnarinone may be a new therapeutic agent for pancreatic cancer

Reconstruction of the Gastrointestinal Tract byhemi-doublestapling Method for the Esophagus andjejunum Using Eea Orvil in Laparoscopic Total Gastrectomy and Proximal Gastrectomy

We report the method of anastomosis based on a hemi-double stapling technique (hereinafter, HDST) using a trans-oral anvil delivery system (EEA OrVil) for reconstructing the esophagus and lifted jejunum following laparoscopic total gastrectomy or proximal gastric resection. As a basic technique, end-to-side anastomosis was used for the cut-off stump of the esophagus and lifted jejunum. After the gastric lymph node dissection, the esophagus was cut off obliquely to the long axis using an automated stapler. EEA OrVil was orally, and a small hole was created at the tip of the obliquely cut-off stump with scissors to let the valve tip pass through. When it was confirmed that the automated stapler and center rod were made completely linear, the anvil and the main unit were connected with each other and firing was carried out. Then, HDST-based anastomosis was completed. The method may safe laparoscopic anastomosis between the esophagus and reconstructed intestine.

Heterogeneic distribution of thymidine phosphorylase between primary tumors and metastatic lesions of human pancreatic ductal carcinoma: implications for the efficacy of chemotherapy with 5-FU or its derivatives

Abstract. Purpose: It has been suggested that the expression of thymidine phosphorylase (TdRPase) correlates with the malignant potential of various cancers, but its involvement in human invasive ductal carcinoma (IDC) of the pancreas has not been reported. In the present study, the distribution and clinical significance of TdRPase in IDCs and benign diseases of the pancreas were assessed, especially in relation to the efficacy of chemotherapy with 5-FU or its derivatives. Method: The expression of TdRPase in 148 specimens of pancreatic IDCs (66 primary lesions, 46 nodal lesions and 36 distant metastases from 126 patients) and in 24 specimens of benign diseases (4 cystadenomas, 3 hyperplasias, and 17 chronic pancreatitises) was examined by immunohistochemical staining with anti-TdRPase monoclonal antibody and evaluated in terms of three grades of immunoreactivity: negative 0, low 1, or high 2. Results: Positive TdRPase staining (low and high immunoreactivity) was detected in 71% (47/66) of the primary lesions, in 46% (21/46) of the involved nodes, in 53% (19/36) of various lesions of distant metastasis, and in 37% (9/24) of the benign diseases. The staining intensity was significantly higher in the IDC tissues than in the benign disease tissues, and significantly lower in the metastatic lesions than in the primary lesions. TdRPase reactivity did not correlate with the survival rate in both resectable and unresectable IDCs. In patients with both primary tumor and nodal involvement, however, high TdRPase activity in involved nodes was significantly associated with a poor prognosis. On the other hand, although adjuvant chemotherapy was found to improve the survival of patients, TdRPase activity in the tumor did not show any significant relationship with the efficacy of chemotherapy with 5-FU or its derivatives. Conclusions: The present study suggested that in pancreatic IDC the activity of TdRPase in primary lesions is different from that in metastatic lesions, and that DNA is synthesized mainly through the salvage pathway in primary lesions and through a de novo pathway in metastatic lesions. This may be one of the reasons for the heterogeneity in chemosensitivity of human pancreatic IDC.

Ki-ras point mutation in codon 12 and expression of p53 in mucin-producing tumor of the pancreas

Mucin-producing tumors (MPTs) of the pancreas show a variety of clinical characteristics, including massive production of mucin in the pancreatic duct, dilatation of the main pancreatic duct, and a better prognosis than common invasive ductal carcinoma (IDC). These characteristics suggest that MPTs and IDCs have different cytomolecular backgrounds. The present study was designed to assess the differences in cytomolecular background between MPTs and IDCs, especially the differences in Ki-ras point mutation (PM) and wild and mutant typep53 expression. Cytomolecular backgrounds were compared in a 13 MPTs [8 carcinomas (MPCas) and 5 benign tumors (MPBTs)] and 36 IDCs. Cytomolecular studies included the evaluation of Ki-ras PM and the expression of Ki-ras p21, wild-typep53 (w-p53), and mutant-typep53 (m-p53). Ki-ras PM was assessed by the allele-specific oligonucleotide dot blot hybridization method, and the expression of p21 andp53 was assessed by an immunohistochemical staining method with monoclonal antibodies. Ki-ras PM was seen in 97% of IDCs and in 77% of MPTs (100% of MPCas and 40% of MPBTs), and MPBTs showed a significantly lower incidence of Ki-ras PM (versus IDC,P < 0.01). Guanine-Guanine-Thymine (GGT) to Guanine-Adenine-Thymine (GAT) mutation was seen in 55% of IDCs and 62% MPTs (87% of MPCas and 20% of MPBTs), and MPCas showed a significantly higher incidence of percent GAT mutation (versus IDC,P < 0.05). Ki-ras p21 was expressed in 43% of IDCs and in 31 % of MPTs (50% of MPCas and 20% of MPBTs). w-p53 and m-p53 were expressed in 51 % and 78% of IDCs and in 54% and 62% of MPTs (38% and 63% of MPCas and 20% and 60% of MPBTs), respectively. In MPBTs, hyperplasias showed higher rates of p21, w-p53, and m-p53 expression than cystadenomas. The study suggested that GAT mutation may be involved in the tumorigenesis of MPTs. It is suggested that MPBTs, especially hyperplasias, may be classified as low-grade malignancies like MPCas.

Insulinoma: Selective arterial calcium injection performed to confirm localization and complete resection

A case of insulinoma is reported in a patient in whom selective arterial calcium injection (SACI) tests were performed both to confirm tumor localization before surgery and to confirm complete tumor removal during surgery. An 18-year-old woman with hypoglycemic episodes was diagnosed with an insulinoma in the pancreatic body demonstrated by celiac arteriography. In a preoperative SACI test, calcium was injected into the splenic artery (SpA), gastroduodenal artery (GDA), and superior mesenteric artery (SMA). Serum immunoreactive insulin (IRI) and proinsulin levels were measured in hepatic venous samples. IRI was markedly increased after the injection of calcium into the GDA and SMA, while there was no response in IRI levels when calcium was injected into the SpA. Therefore, no occult insulinoma was revealed in the distal area fed by the SpA, although the presence of insulinoma was uncertain in the proximal pancreas. In the intraoperative SACI test, calcium was injected into the celiac artery. Insulin (determined by enzyme immunoassay) and proinsulin levels were measured in portal venous samples before and after resection of the tumor. After resection, these levels decreased in response to the calcium stimuli, confirming complete removal of the insulinoma. The SACI test was helpful to localize the insulinoma and was useful to confirm the complete removal of the tumor.

A case of multiple juvenile papillomatosis of the breast and its immunohistochemical pathology

Juvenile papillomatosis (JP) is a benign proliferative disease of the breast affecting young women. Some patients with JP develop breast carcinoma. We recently treated and followed a case of JP in a 16-year-old female, and studied its immunohistochemical characteristics. The patient noticed a small tumor, 5 mm in diameter, in the periareolar region on the medial side of the right breast. She underwent an excisional biopsy and pathology demonstrated JP. However, 6 months later, two new lesions were discovered by routine echogram examination, and were later excised. Immunohistochemistry demonstrated that the JP tumors were negative for estrogen receptor, but positive for progesterone receptor, epidermal growth factor receptor and erbB-2. In addition, tests for p53 were negative and Rb protein was normally expressed. Immunohistochemical analysis suggested that an abnormality in estrogen receptor is important in the pathogenesis of JP, and that the patient had a relatively high risk of developing breast carcinoma, since her JP is multicentric and recurrent. The present study also suggests that immunohistochemical pathology may be beneficial in assessing the malignant potential of JP.