[Complete Remission of Advanced Gastric Cancer with Tumor Embolism in the Right Gastric Vein Treated with Radical Resection after Chemotherapy].

A 74-year-old man presented to our hospital with the chief complaint of epigastric pain; upper gastrointestinal endoscopy revealed a 7-cm-sized type 3 gastric cancer in the lesser curvature of the lower part of the stomach. Abdominal contrast computed tomography revealed a tumor embolus in the right gastric vein; the preoperative diagnosis was cT4a(SE) N3aH0P0M0, cStage ⅢC. Because the cancer could spread during surgical manipulation, performing a safe radical resection was difficult; therefore, we decided to initiate chemotherapy. The patient received 3 courses of trastuzumab plus CapeOX, which led to reduction of the primarylesion, peri-gastric lymph node, and right gastric vein tumor embolus. Partial remission was achieved after chemotherapy; therefore, distal gastrectomy, D2 lymph node dissection, and Roux-en-Y reconstruction were performed. Histopathological examination did not reveal viable tumor cells in the primarylesion, lymph nodes, or tumor embolus, and the histological effect was Grade 3. Currently, the patient is alive without relapse at 9 months post operation. Advanced gastric cancer accompanied with tumor embolism in the gastric vein is commonly observed in patients with liver metastasis and in those with severely progressed state of cancer; many of these patients have poor prognosis. Preoperative chemotherapymaybe effective in cases in which tumor embolism in the gastric vein is identified through preoperative diagnostic imaging.

[Bilateral Metastatic Lung Tumor with Different Primary Organs].

A 72-year-old woman with a history of surgery for left breast cancer was found to have sigmoid colon cancer and solitary pulmonary tumor of left upper lobe. We diagnosed adenocarcinoma of the unknown origin by a transbronchial biopsy. We performed left upper segmentectomy and sigmoidectomy. Left pulmonary tumor was diagnosed metastatic lung tumor from breast cancer. A right pulmonary tumor was confirmed by chest computed tomography(CT) after sigmoidectomy. It was also considered to be metastasis from breast cancer and treated with vinorelbine ditartrate. Since no effect was observed by chemotherapy, tumor was surgically removed by wedge resection. Right pulmonary tumor was pathologically diagnosed as metastasis from sigmoid colon cancer. In suspicious case of pulmonary metastases from double cancer, the possibility of different lesions from different primary site should be kept in mind.

Metastatic tumors in the duodenum: A report of two cases.

Two cases are presented involving a 71-year-old male with adenocarcinoma of the lung and a 57-year-old male with adenocarcinoma of the sigmoid colon, each with metastatic lesions located in the duodenal bulb. Each lesion appeared as a submucosal tumor with an ulcer at the center. Lymph node swelling in the hepatoduodenal ligament was also found to precede the emergence of each duodenal metastasis. These cases indicate that involvement of the lymph node in the hepatoduodenal ligament may be a forerunner of duodenal metastasis.

Localization of heparanase in esophageal cancer cells: respective roles in prognosis and differentiation.

In this study, we examined the distribution of heparanase protein in 75 esophageal squamous cell carcinomas by immunohistochemistry and analyzed the relationship between heparanase expression and clinicopathological characteristics. In situ hybridization showed that the mRNA expression pattern of heparanase was similar to that of the protein, suggesting that increased expression of the heparanase protein at the invasive front was caused by an increase of heparanase mRNA in tumor cells. Heparanase expression correlated significantly with depth of tumor invasion, lymph node metastasis, tumor node metastasis (TNM) stage and lymphatic invasion. Overexpression of heparanase in esophageal cancers was also associated with poor survival. In addition to its localization in the cytoplasm and cell membrane, heparanase was also identified in the nuclei of normal epithelial and tumor cells by immunohistochemistry. Furthermore, nuclear heparanase was detected in nuclear extract of cancer cell lines by Western blot and immunohistochemistry. Examination of the role of nuclear heparanase in cell proliferation and differentiation by double immunostaining for proliferating cell nuclear antigen (PCNA) and cytokeratin 10 (CK10) showed significant relationship between nuclear heparanase expression and differentiation (heparanase vs CK10), but not for proliferative state of esophageal cancer cells (heparanase vs PCNA). Our results suggest that cytoplasmic heparanase appears to be a useful prognostic marker in patients with esophageal cancer and that nuclear heparanase protein may play a role in differentiation. Inhibition of heparanase activity may be effective in the control of esophageal tumor invasion and metastasis.

Molecular mechanism of chemoresistance to cisplatin in ovarian cancer cell lines.

It is important to clarify the mechanism of resistance to cisplatin for the treatment of solid tumors. We have examined the expression of apoptosis-related proteins, Bax and Bcl-2, in ovarian cancer cells. We used the cell line 2008 and its cisplatin resistant subclone 2008 C-13. The percentage of 2008 cells showing apoptosis was significantly higher following cisplatin treatment as compared to untreated controls. 2008 C-13 cells showing apoptosis did not differ between the cisplatin-treated group and the untreated group. The expression of mRNA and protein of Bax in the two cell lines were not altered by treatment with cisplatin. Although the expression of mRNA and protein of Bcl-2 decreased in 2008 cells after treatment with cisplatin, the expression of Bcl-2 remained unchanged in 2008 C-13 cells. Our results indicate that the down-regulation of Bcl-2 plays an important role in the mechanisms of tumor resistance to anticancer drugs.

Cyclin A correlates with the sensitivity of human cancer cells to cytotoxic effects of 5-FU.

We investigated the role of cyclin A in the cytotoxic effect of 5-fluorouracil (5-FU) on cancer cell lines. Experiments were performed using gastric cancer chemosensitive NUGC3, and chemoresistant NUGC3/5FU/L established by repeated exposure to 5-FU. 5-FU inhibited cell growth of NUGC3 in a dose-dependent manner. Low concentrations of 5-FU did not inhibit cell growth of NUGC3/5FU/L, while high concentrations slightly inhibited cell growth. Examination of the cell cycle pattern of NUGC3 cells showed accumulation at S-phase at 10 micro M and at G1-S-phase at 100 micro M of 5-FU. Cell cycle pattern of NUGC3/5FU/L cells did not change 5-FU concentrations. 5-FU increased cyclin A mRNA level in NUGC3 cells but not NUGC3/5FU/L cells. In the presence of 100 micro M 5-FU, cyclin A protein level increased 2.6-fold in NUGC3 and 1.47-fold in NUGC3/5FU/L. 5-FU dose-dependently increased the percentage of cyclin A-positive NUGC3 cells, but not NUGC3/5FU/L cells. The percentage of cyclin A-positive cells in other 5-FU sensitive esophageal, colon and gastric cancer cell lines (T.Tn, LOVO, DLD-1, MKN-7), increased in the presence of 1 and 10 micro M 5-FU, while cyclin A-positive cells in 5-FU resitant hepatocellular and colon carcinoma cell lines (HCC50 and C-1), did not increase with the same treatment. Our results indicate that the cytotoxic effects of 5-FU in human cancer cell lines correlate with cyclin A and it may be used as a predictive factor for chemotherapy response.

Inhibition of inducible NF-kappaB activity reduces chemoresistance to 5-fluorouracil in human stomach cancer cell line.

5-fluorouracil (5-FU) is used for the treatment of stomach and colon cancer, but many tumors are resistant to this chemotherapeutic agent. 5-FU induces apoptosis of several cancer cell lines, while some chemotherapeutic agents are known to activate the transcriptional factor NF-kappaB, which strongly suppresses apoptosis in vitro. In the present study, we investigated the relationship between activation of NF-kappaB and chemoresistance to 5-FU in human stomach cancer cell lines, NUGC3 (5-FU sensitive) and NUGC3/5FU/L (5-FU resistant). Treatment with 5-FU for 9-12 h caused activation of inducible NF-kappaB in NUGC3/5FU/L cells but not in NUGC3 cells. 5-FU also resulted in an increase in the number of TUNEL-positive cells and enhanced caspase-3 activity 3- to 5-fold in NUGC3 cells but not NUGC3/5FU/L cells. Moreover we also demonstrated that the inhibition of inducible NF-kappaB activation by using a NF-kappaB decoy could induce apoptosis and reduce chemoresistance against 5-FU. Our results suggest that 5-FU chemoresistance can be overcome by inhibition of inducible NF-kappaB activation, and that the use of the NF-kappaB decoy combined with 5-FU treatment is a new molecular and gene therapeutic strategy aimed at treatment of human stomach cancers resistant to 5-FU.

Heparanase expression correlates with invasion and poor prognosis in gastric cancers.

Degradation of basement membrane and extracellular matrix structures are important features of the metastatic process of malignant tumors. Human heparanase degrades heparan sulfate proteoglycans, which represent the main components of basement membranes and the extracellular matrix. Because of the role of heparanase in tumor invasion and metastasis, we examined heparanase expression in primary gastric cancers and in cell lines derived from gastric cancers by immunohistochemistry and RT-PCR, respectively. Four of seven gastric cancer cell lines showed heparanase mRNA expression by RT-PCR. Heparanase protein was detected in both the cytoplasm and the nucleus of heparanase mRNA-positive cells by immunohistochemical staining. Heparanase expression was confirmed in 35 (79.5%) of 44 gastric tumor samples by immunohistochemical staining. However, no or weak heparanase expression was detected in normal gastric mucosa. In situ hybridization showed that the mRNA expression pattern of heparanase was similar to that of the protein, suggesting that increased expression of the heparanase protein at the invasive front was caused by an increase of heparanase mRNA in tumor cells. Analysis of the clinicopathologic features showed stronger heparanase expression in cases of huge growing tumors, extensive invasion to lymph vessels, and regional lymph node metastasis. In gastric cancer, patients with heparanase expression showed significantly poorer prognosis than those without such expression (p = 0.006). In conclusion, our findings suggest that high expression of heparanase in gastric cancer is a strong predictor of poor survival.