Correlation of integrin β3 mRNA and vascular endothelial growth factor protein expression profiles with the clinicopathological features and prognosis of gastric carcinoma

AIM: To investigate integrin β3 mRNA and vascular endothelial growth factor (VEGF) protein expression in gastric carcinoma, and its correlation with microvascular density, growth-pattern, invasion, metastasis and prognosis.

METHODS: In situ hybridization (ISH) of integrin β3 mRNA and immunohistochemistry of VEGF and CD34 protein were performed on samples from 118 patients with gastric cancer.

RESULTS: The positive rate of integrin β3 mRNA in non-tumor gastric mucosa (20%) was significantly lower than that of the gastric cancer tissue (52.5%, χ² = 10.20, P < 0.01). In patients of infiltrating type, stage T₃-T₄, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of integrin β3 mRNA were significantly higher than those in patients of expanding type (P < 0.01), stage T₁-T₂ (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T₃-T₄, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of VEGF protein were significantly higher than those in patients of expanding type (P < 0.01), stage T₁-T₂ (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T₃-T₄, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the mean MVD were significantly higher than those in patients of expanding type (P < 0.01), stage T₁-T₂ (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. It was found that the positive expression rate of integrin β3 mRNA was positively related to that of VEGF protein (P < 0.01) and MVD (P < 0.05), meanwhile the positive expression rate of VEGF protein was positively related to MVD (P < 0.05). The mean survival period in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm² was significantly shorter than that in patients with negative expression of integrin β3 mRNA (P < 0.05) and VEGF (P < 0.01), and MVD < 54.9/mm² (P < 0.01). Five-year survival rate in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm² was significantly lower than those with negative expression of integrin β3 mRNA (P < 0.05), VEGF (P < 0.05), and MVD < 54.9/mm² (P < 0.01).

CONCLUSION: Integrin β3 and VEGF expression can synergistically enhance tumor angiogenesis, and may play a crucial role in invasion and metastasis of gastric carcinoma. Therefore, they may be prognostic biomarkers and novel molecular therapeutic targets.

Exophytic inflammatory myofibroblastic tumor of the stomach in an adult woman: A rare cause of hemoperitoneum

Inflammatory myofibroblastic tumor (IMT) of the stomach in adults is extremely rare, with unpredictable prognosis. We present a 55-year-old woman with a gastric IMT. She experienced sudden abdominal pain 4 d previously. Physical examination showed mild abdominal tenderness in the hypogastrium, but no palpable abnormal abdominal mass. Abdominal CT showed a mass of approximately 8 cm in the gastrocolic ligament. On laparoscopic exploration, unexpected hemoperitoneum of approximately 1.5 L of blood was found, and an exophytic gastric mass of approximately 10 cm, appeared from the anterior wall of the gastric body along the greater curvature. Laparoscopy further showed that non-clotting blood in the abdominal cavity seemed to be from the gastric tumor. After conversion to open surgery for more precise evaluation of the cause of hemoperitoneum and the large friable tumor, gastric wedge resection, including the tumor, was conducted. The final diagnosis was consistent with IMT that originated from the gastric wall.

Clinical significance of multi-slice spiral CT and serum tumor markers in the preoperative assessment of gastric carcinoma

AIM: To investigate the value of multi-slice spiral CT (MSCT) and serum tumor markers in the preoperative assessment of gastric carcinoma.

METHODS: MSCT was performed preoperatively in 220 patients with gastric carcinoma confirmed by biopsy, and the results were compared with surgical pathological findings. In addition, preoperative serum tumor marker levels of CA125, CA19-9, CA72-4, CEA and AFP were measured, and the correlation between tumor marker levels and clinicopathological parameters of gastric carcinoma was analyzed.

RESULTS: The overall accuracy of MSCT in preoperative T staging of gastric carcinoma was 78.64%. The overall accuracy of MSCT in preoperative N staging of gastric carcinoma was 74.09%. The diagnostic sensitivity, specificity and accuracy of MSCT for determining distant metastases of gastric carcinoma were 65.63%, 99.47% and 94.55%, respectively. The diagnostic sensitivity of MSCT was 83.33% for hepatic metastasis, 33.33% for peritoneal metastasis, and 78.57% for distant lymph node metastasis. The overall accuracy of MSCT for determination of TNM stage of gastric carcinoma was 58.54%. The accuracy of MSCT in evaluating resectability of gastric carcinoma was 91.36%. Receiver operating characteristics analysis showed that the accuracy of serum CA125 for determination of depth of invasion, distant metastasis, peritoneal metastasis, and TNM stage of gastric carcinoma was relatively high. The accuracy of serum CA19-9 for determination of surgical resectability was relatively high. In addition, the accuracy of serum CA72-4 for determination of peritoneal and distant lymph node metastasis of gastric carcinoma was relatively high. The recommended cut-off value of serum CEA and AFP was 10 mg/L and 11 mg/L, respectively. The serum CEA level was closely related to gender, maximum diameter of gastric carcinoma, histological type, depth of invasion, distant metastasis, distant lymph node metastasis, and TNM stage. However, there was no significant correlation between serum AFP level and age, gender, tumor location, maximum tumor diameter, histological type, depth of invasion, lymph node, distant, hepatic, peritoneal and distant lymph node metastasis, TNM stage; and surgical resectability.

CONCLUSION: The clinical value of MSCT and serum CA125, CA19-9, CA72-4 and CEA in the preoperative assessment of gastric carcinoma is relatively high. However, serum AFP has limited value in the preoperative assessment of gastric carcinoma.

Oxaliplatin, 5-FU, folinic acid as first-line palliative chemotherapy in elderly patients with metastatic or recurrent gastric cancer

PURPOSE

We investigated the efficacy and safety of a combination of oxaliplatin, 5-fluorouracil (5-FU), and folinic acid (FA) as first-line palliative chemotherapy for elderly patients with metastatic or recurrent gastric cancer.

MATERIALS AND METHODS

The study patients were chemotherapy-naïve patients (> 65 years old) with histologically confirmed, metastatic or recurrent gastric cancer. Chemotherapy consisted of oxaliplatin 100 mg/m(2) and FA 100 mg/m(2) (2-hour infusion), and then 5-FU 2400 mg/m(2) (46-hour continuous infusion) every 2 weeks.

RESULTS

A total of 37 patients were studied between April 2004 and October 2006. Of the 34 evaluable patients, none achieved a complete response (CR) and 14 achieved a partial response (PR), resulting in an overall response rate of 41.2%. The median time to progression (TTP) was 5.7 months (95% CI: 4.2~6.3 months) and the median overall survival (OS) was 9.8 months (95% CI: 4.4~12.0 months). The main hematologic toxicities were anemia and neutropenia, which were observed in 56.7% and 32.4% of the patients, respectively. Grade 3/4 neutropenia was observed in 8.1% of the patients. None of the patients experienced febrile neutropenia. Peripheral neuropathy occurred in 35.1% of the patients and all were grade 1/2.

CONCLUSION

This oxaliplatin/5-FU/FA regimen showed good efficacy and an acceptable toxicity profile in elderly patients with metastatic or recurrent gastric cancer.

Apoptotic effect of Epigallocatechin-3-gallate on the human gastric cancer cell line MKN45 via activation of the mitochondrial pathway

AIM: To investigate whether Epigallocatechin-3-gallate (EGCG) can induce apoptosis of the gastric cancer cell line MKN45 and its apoptotic pathway.

METHODS: To determine this, apoptotic rates of MKN45 cells after EGCG treatment with or without caspase-3 inhibitor were evaluated by Annexin V-FITC + PI staining The influence of EGCG on the activity of caspase-3 in the MKN45 cells was determined by ELISA. By Rhodamine123 staining, the membrane potential change of the mitochondrion was also investigated, and mRNAs and protein expression of the bcl-2 family were analyzed by RT-PCR and Western blot.

RESULTS: EGCG can induce apoptosis of MKN45 cells in time- and dose-dependent manner. Eight hours after EGCG treatment, the activity of caspase-3 in the MKN45 increased, especially 12 h after treatment. The mitochondrial membrane potential was significantly weakened 4 h after EGCG insult. The mRNA and protein expression levels of pro-apoptotic members, such as Bax, Bid and Bad, were upregulated gradually as treated time increased. Moreover, the mRNA and protein expression levels of anti-apoptotic members, such as Bcl-xL and Bcl-2, were inhibited.

CONCLUSION: These data support that EGCG can induce apoptosis of the human gastric cancer cell line MKN45, and the effect is in a time- and dose-dependent manner. The apoptotic pathway triggered by EGCG in MKN45 is mitochondrial-dependent.

Phase II study of docetaxel and cisplatin as first-line chemotherapy in patients with recurrent or metastatic gastric cancer

PURPOSE

Palliative chemotherapy for patients with recurrent or metastatic gastric cancer has been shown to have a survival benefit. Docetaxel monotherapy has achieved appreciable results for treating gastric cancer. We investigated the clinical efficacy and feasibility of a docetaxel and cisplatin combination regimen for patients suffering with recurrent or metastatic gastric cancer.

MATERIALS AND METHODS

Patients with histologically proven, bidimensionally measurable lesions of recurrent or metastatic gastric cancer, and they had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 and no prior palliative chemotherapy were eligible for this study. The combination chemotherapy regimen consisted of docetaxel 75 mg/m(2) plus cisplatin 75 mg/m(2) on day 1, and this was repeated every 3 weeks until disease progression.

RESULTS

32 patients were enrolled from 2002 to 2005. The objective response rate was 31.3% (95% confidence interval (CI): 14.2 approximately 48.2%) with no CR. The disease control rate was 59.4%. At a median follow up of 38.9 months, the median overall survival was 7.4 months (95% CI: 6.3 approximately 8.5). The median time to progression was 4.7 months (95% CI: 3.1 approximately 6.3). During a total of 106 cycles, grade 3 or 4 hematological toxicities were observed as follows: neutropenia (39 of 106 cycles) and anemia (3 of 106 cycles). The grade 3 or 4 non-hematological toxicities included anorexia (18.9%) and nausea/vomiting (21.7%).

CONCLUSION

Docetaxel and cisplatin combination chemotherapy showed promising anti-tumor activity and this was well tolerated as a first-line treatment for patients with recurrent or metastatic gastric cancer. Further large, randomized phase III studies are warranted.

Effect of cimetidine on the proliferation and apoptosis of human gastric cancer cell line SGC-7901

AIM: To investigate the effect of cimetidine on the proliferation and apoptosis of human gastric cancer cell line SGC-7901 and its related mechanism.

METHODS: Human gastric cancer cell SGC-7901 was cultivated by routine method, then treated with different concentrations of cimetidine. The proliferation of SGC-7901 cells was examined by MTT assay, and the cell cycle and apoptosis were detected by flow cytometry. After Hoechst33258 staining, the morphologic changes of SGC-7901 cells were observed under fluorescence microscope, and the ultrastructure of the cells was investigated by transmission electron microscopy. The levels of Bcl-2 and Bax protein expression were detected by Western blot analysis.

RESULTS: After dealing with cimetidine (0.5, 1, 2.5, 5, 10 mmol/L) for 24 and 48 hours, we found that cimetidine significantly inhibited the proliferation of SGC-7901 cells in a time- and concentration-dependent manner (24 h: 0.705 ± 0.018, 0.560 ± 0.038, 0.408 ± 0.029, 0.276 ± 0.042, 0.205 ± 0.031 vs 0.803 ± 0.012, P < 0.05; 48 h: 0.902 ± 0.024, 0.671 ± 0.015, 0.420 ± 0.030, 0.180 ± 0.037, 0.117 ± 0.021 vs 1.079 ± 0.040, P < 0.05), whereas there was no significant cytotoxic effect as the concentration was below 0.25 mmol/L. cimetidine at the concentrations of 0.5, 1, 2.5, 5, and 10 mmol/L induced typical apoptosis of SGC-7901 cells, and flow cytometry showed an apoptosis peak. The percentage of G0/G1-phase cells was significantly increased (60.83% ± 2.27%, 67.21% ± 1.18%, 75.15% ± 4.01%, 81.88% ± 3.10%, 86.99% ± 1.43% vs 50.28% ± 1.97%, P < 0.05). The expression of Bcl-2 protein was decreased while that of Bax protein was increased following cimetidine treatment.

CONCLUSION: Cimetidine may inhibit the proliferation of SGC-7901 cells through inducing cell apoptosis and cell cycle arrest.

The synergism between Belotecan and cisplatin in gastric cancer

PURPOSE

We wanted to demonstrate the anti-cancer effect and interaction between belotecan and cisplatin on gastric cancer cell line and we evaluated the mechanisms of this synergistic effect in vitro.

MATERIALS AND METHODS

The growth inhibitory effect of belotocan and cisplatin against several gastric cancer cell lines (SNU-5, SNU-16 and SNU-601) was estimated by tetrazolium dye assay. The effect of a combination treatment was evaluated by the isobologram method. The biochemical mechanisms for the interaction between the drugs were analyzed by measuring the formation of DNA interstrand cross-links (ICLs) and DNA topo-I activity.

RESULTS

Belotecan showed synergism with cisplatin for growth inhibitory effect on the gastric cancer cell lines SNU-5, and SNU-16, but this was subadditive on the SNU-601 cell line. The formation of DNA ICLs in SNU-16 cells by cisplatin was increased by combination with belotecan, but this was not affected in SNU-601 cells. The topo-I inhibition by belotecan was enhanced at high concentrations of cisplatin in SNU-16, but not in SNU-601 cells.

CONCLUSION

Belotecan and cisplatin show various combination effect against gastric cancer cells. The synergism between cisplatin and belotecan could be the result of one of the following mechanisms: the modulating effect of belotecan on the repair of cisplatin-induced DNA adducts and the enhancing effect of cisplatin on the belotecan-induced topo-I inhibitory effect.

Long-term survival after surgical resection for liver metastasis from gastric cancer: two case reports

Surgical resection of colorectal cancer metastasis to the liver results in a 5-year survival rate of around 40%. Liver metastasis from other cancers such as neuroendocrine carcinoma and genitourinary tumors are also treated effectively with combined liver resection. However, hepatic metastasectomy for liver tumor from gastric cancer hasn't been considered as a standard treatment, and the benefit for this treatment has not been established. We report here on two cases of gastrectomy and combined liver resection for synchronous liver metastasis without any evidence of other metastatic lesions, and these two patients have survived for more than 7 years without evidence of disease recurrence. In conclusion, for patients with hepatic metastasis from gastric cancer, combined surgical resection of the liver metastasis should be considered as a treatment option when metastasis to other sites can be excluded.

Neuroendocrine gastric carcinoma expressing somatostatin: A highly malignant, rare tumor

Poorly differentiated gastric neuroendocrine carcinomas, although rare, deserve particular attention, as they are aggressive and have an extremely poor prognosis. In this report we describe a gastric neuroendocrine carcinoma with rapidly fatal outcome. Immunohistological staining of the resected specimens revealed that the tumor was an endocrine carcinoma. The tumor disclosed intense immunoreactivity to pan-neuroendocrine markers and diffuse somatostatin immunoreactivity. There were no psammoma bodies and no demonstrable association with von Recklinghausen’s neurofibromatosis. In the gastrointestinal tract, neuroendocrine tumors producing predominantly somatostatin have been described only in the duodenum. To the best of our knowledge, the present report is the second case report of a neuroendocrine gastric carcinoma expressing diffusely somatostatin as the only neuroendocrine regulatory peptide.

Extremely well-differentiated adenocarcinoma of the stomach: Clinicopathological and immunohistochemical features

AIM: Minimal deviation carcinoma of the uterine cervix, otherwise known as extremely well-differentiated adenocarcinoma (EWDA), is characterized by its benign microscopic appearance in contrast to its aggressive behavior. In order to elucidate the clinicopathological features and biological behavior of the gastric counterpart of EWDA, we, using immunohistochemistry, analyzed nine lesions for the phenotypic expression, proliferative activity, and the expression of oncogene-associated products.

METHODS: Clinicopathological features, including pre-operative biopsy diagnosis, were reviewed. Using immunohitstochemistry, Ki-67 labeling index and expression of p53 and c-erbB-2 protein in the gastric lesions were detected.

RESULT: Locations in the middle or upper third of the stomach and polypoid macroscopic features are characteristic of EWDA of the stomach. Although 4 of the 9 lesions showed only focal lymphatic or venous invasion, lymph node metastasis was not present and none of the patients died of the lesions (mean follow-up period, 56 mo). All 9 cases of EWDA could be classified into gastric phenotype (5 lesions) and intestinal phenotype (4 lesions). The former resembled gastric foveolar epithelium, mucous neck cells or pyloric glands, but their papillary structures were frequently elongated and the tumor cells and their nuclei were slightly larger and more hyperchromatic compared to normal epithelium. The latter resembled intestinal metaplasia with minimal nulcear atypia and irregular glands; two of these lesions demonstrated complete intestinal phenotype, while two demonstrated incomplete intestinal phenotype. Ki-67 labeling index was low and none of the cases revealed over-expression of p53 and c-erbB-2 protein.

CONCLUSION: Unlike minimal deviation carcinoma of the cervix, these findings suggest that EWDA of the stomach is a lesion of low-grade malignancy. This favorable biological behavior is supported by the data of a low Ki-67 labeling index and a lack of p53 or c-erbB-2 protein over-expression. Because of its resemblance to normal gastric mucosa or mucosa with intestinal metaplasia, EWDA is often misdiagnosed. To prevent the misdiagnosis of such lesions, the clinical and pathologic characteristics should be taken into consideration.

Antisense angiopoietin-1 inhibits tumorigenesis and angiogenesis of gastric cancer

AIM: To investigate the effect of angiopoietin-1 (Ang-1) on biological behaviors in vitro and tumorigenesis and angiogenesis in vitro of human gastric cancer cells.

METHODS: Human full-length Ang-1 gene was cloned from human placental tissues by RT-PCR method. Recombinant human Ang-1 antisense eukaryotic expression vector was constructed by directional cloning, and transfected by lipofectin method into human gastric cancer line SGC7901 with high Ang-1 expression level. Inhibition efficiency was confirmed by semi- quantitive PCR and Western blot method. Cell growth curve and cell cycle were observed with MTT assays and flow cytometry, respectively. Nude mice tumorigenicity test was employed to compare in vitro tumorigenesis of cells with Ang-1 suppression. Microvessel density (MVD) of implanted tumor tissues was analyzed by immunohistochemistry for factor VIII staining.

RESULTS: Full-length Ang-1 gene was successfully cloned and stable transfectants were established, namely 7Ang1- for antisense，and 7901P for empty vector transfected. 7Ang1- cells showed down-regulated Ang-1 expression, while its in vitro proliferation and cell cycle distribution were not significantly changed. In contrast, xenograft of 7Ang1- cells in nude mice had lower volume and weight than those of 7901P after 30 days’ implantation (P < 0.01, 293.00 ± 95.54 mg vs. 624.00 ± 77.78 mg) accompanied with less vessel formation with MVD 6.00±1.73 compared to 7901P group 8.44±1.33 (P < 0.01).

CONCLUSION: Ang-1 may play an important role in tumorigenesis and angiogenesis of gastric cancer, and targeting its expression may be beneficial for the therapy of gastric cancer.

Increased ERCC expression correlates with improved outcome of patients treated with cisplatin as an adjuvant therapy for curatively resected gastric cancer

PURPOSE

It has been reported that the overexpression of the excision repair cross-complementing 1 (ERCC1) gene, which is essential for the repair of cisplatin (CDDP)-DNA adducts, negatively influences the effectiveness of CDDP-based therapy for primary gastric cancer. We investigated whether the ERCC1 expression was associated with survival for gastric cancer patients in an adjuvant setting.

MATERIALS AND METHODS

We retrospectively analyzed 44 patients who were diagnosed with stage II or higher disease after undergoing curative resection and they had also received cisplatin-based chemotherapy. The ERCC1 expression was examined by performing immunohistochemical (IHC) staining, and this was divided into two groups according to the percentage of IHC staining of the tumor cell nuclei (negative: 10% or less, positive: more than 10%).

RESULTS

Among the 44 patients (ERCC1-negative/ERCC1-positive group=16/28), 32 patients were male and their median age was 52 years. There was no difference for the baseline characteristics of the two groups. The median follow-up duration was 41 months. The median disease-free survival (DFS) and the overall survival (OS) for the ERCC1-positive group were significant higher than those of the ERCC1-negative group (DFS: 40.4 vs. 14.6 months, p=0.02, OS: undefined vs. 20.4 months, p=0.008).

CONCLUSION

The overall survival in gastric cancer patients who received cisplatin-based adjuvant chemotherapy after a curative resection is higher in those patients showing the overexpression of the ERCC1 gene. However, prospective studies using the ERCC1 gene expression as a prognostic marker for the DNA repair activity are needed.

Prognostic factors for advanced gastric cancer: stage-stratified analysis of patients who underwent curative resection

PURPOSE

Advanced gastric cancer patients have a poorer prognosis as compared to the patients with early gastric cancer. This study was conducted to define the prognostic factors for advanced gastric cancer.

MATERIALS AND METHODS

606 patients with advanced gastric cancer who underwent curative gastric resection at our hospital were retrospectively examined. The patients were divided into two groups: group 1 was comprised of patients with a survival time <5 years, and group 2 patients had a survival time >or=5 years. We compared clinicopathological characteristics of the two groups by performing univariate and multivariate analysis. We also investigated the prognostic factors according to the stage.

RESULTS

On univariate analysis, 7 factors (age, tumor size, Borrmann type, resection type, distal resection margin, depth of invasion and lymph node status) were found to be different, and multivariate analysis revealed that patient age, depth of invasion and lymph node metastasis were the only significantly differences between the two groups. On the other hand, age and the Borrmann type for stage I b patients, age and the number of retrieved lymph nodes for stage II patients, tumor size for stage III patients, and the type of resection for stage IV patients were found to be the independent prognostic factors.

CONCLUSION

The age of patients had prognostic value in the early stages of advanced gastric cancers such as stage I b or II. The number greater than 20 retrieved lymph nodes affected the survival, particularly for the patients with stage II disease, and the tumor size was a significant prognostic factor for patients with stage III disease. Therefore, physicians are advised to pay special attention to lymph node dissection for those patients with stage II or III disease.

Characteristics of synchronous cancers in gastric cancer patients

PURPOSE

The primary objective of the current study was to investigate the characteristics of synchronous cancers in gastric cancer patients.

MATERIALS AND METHODS

We analyzed the 2,237 patients who were diagnosed between December 2000 and December 2003 with gastric cancer and synchronous cancers of organs other than the stomach.

RESULTS

73 (3.3%) of a total of 2,237 gastric cancer patients had synchronous primary cancers. Among these 73 patients, 71 had one synchronous cancer, and two patients had double synchronous cancers. Colorectal cancer (26 patients, 34.7%) was the most frequently encountered synchronous cancer, followed by cancer of the lung (16 patients, 21.3%), esophagus (13 patients, 17.2%), and liver (8 patients, 10.7%). Synchronous cancers were detected with increased frequency in the elderly, in the patients with multiple gastric cancers, in the patients with differentiated gastric cancer, and in the patients with early gastric cancer, as determined on univariate analysis, but the differentiation of gastric cancers was the only risk factor for synchronous cancers on the multivariate analysis.

CONCLUSIONS

The differentiation of gastric cancer cells may be a risk factor for synchronous cancers in gastric cancer patients. Careful surveillance by the physician for synchronous cancer is warranted for the patients suffering from gastric cancer.

A multi-center, phase ii clinical trial of Padexol (paclitaxel) and cisplatin for patients suffering with advanced gastric cancer

PURPOSE

We conducted a multi-center, phase II trial to evaluate the efficacy and safety of using Padexol (a paclitaxel formulation) combined with cisplatin for the patients suffering with advanced gastric adenocarcinoma.

MATERIALS AND METHODS

39 patients (median age: 60 years; males: 90%) who were diagnosed with advanced gastric cancer were enrolled from 5 hospitals. Padexol 175 mg/m² was administered as a 3-hr infusion, and this was followed by cisplatin 75 mg/m² as an intravenous infusion on day 1, once every 3 weeks.

RESULTS

Out of these 39 patients, 34 patients were assessable for treatment efficacy and 39 patients were assessable for the toxicity. Objective responses occurred in 13 patients (33%); 1 patient (3%) had a complete response and 12 patients (31%) had partial responses. 6 patients (15%) achieved a stable disease state. The median duration of response was 7.1 months, and the median time to progression and the overall survival were 4.8 months and 6.7 months, respectively. The major treatment-related adverse events were hematologic toxicity, including WHO grade 3 or 4 neutropenia in 13 patients (33%). However, febrile neutropenia occurred in only 1 patient and the non-hematologic toxicity was usually mild.

CONCLUSION

The combination of Padexol and cisplatin was found to be active and it seems to be a relatively well-tolerated regimen for the treatment of advanced gastric cancer.

Oxaliplatin with biweekly low dose leucovorin and bolus and continuous infusion of 5-fluorouracil (modified FOLFOX 4) as a salvage therapy for patients with advanced gastric cancer

PURPOSE

To determine the activity and the toxicity associated with a low dose regimen of leucovorin (LV) plus 5-fluorouracil (5-FU) combined with oxaliplatin every two weeks (modified FOLFOX 4) as a salvage therapy for advanced gastric cancer patients.

MATERIALS AND METHODS

Between December 2003 and December 2004, 33 patients were enrolled in this study. The patients were treated with oxaliplatin 85 mg/m(2) as a 2-hour infusion on the first day plus LV 20 mg/m(2) over 10 minutes. Subsequently, the patients were given a 5-FU bolus 400 mg/m(2) followed by a 22-hour continuous infusion of 600 mg/m(2) on days 1 approximately 2. The treatment was repeated at 2 week intervals.

RESULTS

The median age of the patients was 50 years (range: 31 approximately 74), 82% (27/33) had the Eastern Cooperative Oncology Group performance status was 0 and 1. Of the 30 patients who could be evaluated for their tumor response, 8 achieved a partial response, with an overall response rate of 26.7% (95% confidence interval (CI): 20.5 approximately 32.7%). Fifteen patients (50%) showed stable disease and 7 patients (23.3%) progressed during the course of treatment. The median time from the start of chemotherapy to progression was 3.5 months (95% CI: 2.6 approximately 4.4 months) and the median overall survival time was 7.9 months (95% CI: 5.9 approximately 9.9 months). The major grade 3/4 hematological toxicity encountered included neutropenia (45.4%) and thrombocytopenia (3.0%). Neutropenic fever occurred during only 2 of the 178 cycles. The most common non-hematological toxicity encountered was grade 1/2 nausea/vomiting, which occurred in 18.2% of patients, diarrhea in 12.1% and neuropathy in 15.2%. There were no treatment related deaths.

CONCLUSION

The modified FOLFOX 4 regimen appears to be a safe and effective salvage therapy for advanced gastric cancer patients.

Epstein-Barr virus in human malignancy: a special reference to Epstein-Barr virus associated gastric carcinoma

Epstein-Bar virus (EBV), a human herpesvirus, establishes a life-long persistent infection in 90 approximately 95% of human adult population worldwide. EBV is the etiologic agent of infectious mononucleosis, and EBV is associated with a variety of human malignancy including lymphoma and gastric carcinoma. Recently, EBV has been classified as group 1 carcinogen by the WHO International Agency for Research on Cancer. Evidence is presented which suggests that failures of the EBV-specific immunity may play a role in the pathogenesis of EBV-associated malignancy. At present, the precise mechanisms by which EBV transforms B lymphocytes have been disclosed. Encouragingly, they have had enough success so far to keep them enthusiastic about novel therapeutic trial in the field of EBV-associated lymphoma. However, information on EBV-associated gastric carcinoma is still at dawn. This article reviews EBV biology, immunological response of EBV infection, unique oncogenic property of EBV, peculiarity of EBV-associated gastric carcinoma, and lastly, EBV-targeted therapy and vaccination.

A phase II trial of haptaplatin/5-FU and leucovorin for advanced stomach cancer

PURPOSE

Heptaplatin (SKI-2053 R) is a new platinum analogue, with a better toxicity profile than cisplatin, and has antitumor activity even in cisplatin resistant cell lines. 5-fluoruracil (5-FU) has shown synergy with platinum compounds. This phase II trial was designed to determine the efficacy and toxicities of heptaplatin/ 5-FU (5-fluorouracil) for treating stomach cancer.

MATERIALS AND METHODS

Thirty-two patients with advanced, measurable gastric adenocarcinomas were enrolled in this trial. The treatment consisted of heptaplatin, 400 mg/m(2)/day (1 hour IV infusion), on day 1 and 5-FU, 800 mg/m(2)/day (12 hours IV infusion), on days 1 to 5. The cycles were repeated every 3 weeks.

RESULTS

Of the 26 evaluable patients, 9 had partial responses and 1a complete response (overall response rate, 38%; 95% confidence interval, 19 approximately 57%). The median response duration was 23 weeks (range: 4 approximately 60 weeks). The median time to progression was 26 weeks (range: 3 approximately 68 weeks). The grades III-IV toxicities were mostly hematological toxicities: leucopenia was observed in 11 patients (35%) and thrombocytopenia 4 (13%). No definite neuropathy was observed. Grade I-II nephropathy was also noted: grade I high BUN/creatinine levels occurred in 5 patients (16%), grade II proteinuria 2 (6%), grade I proteinuria 5 (16%). Neutropenic fever developed in 5 patients (16%) and 1 died of pneumonia in a neutropenic state.

CONCLUSION

This study suggests that the regimen of Heptaplatin/5-FU should be effective and have a favorable toxicity profile for the patients suffering with advanced stomach cancer.

Efficacy and safety study of docetaxel as salvage chemotherapy in metastatic gastric cancer failing fluoropyrimidine and platinum combination chemotherapy

PURPOSE

Fluoropyrimidine (F) and platinum (P) combination chemotherapy has been widely used for the first line treatment of advanced gastric cancer (AGC). Docetaxel (D) has shown promising activity in this disease. The present study retrospectively investigated the efficacy of D monotherapy as salvage chemotherapy for AGC that is failing F and P combination chemotherapy.

MATERIALS AND METHODS

A total of 34 patients, fitting the eligibility criteria, were included in this study. D was administered at a dose of 75 mg/m(2) IV every 3 weeks, with dexamethasone prophylaxis. Twenty-nine patients had measurable lesions. The median treatment-free interval was 38.5 days, and 91.2% of patients had progressed within 4 months of withdrawal of the first line chemotherapy.

RESULTS

A total of 133 cycles of D were administered, with a median of 3.5 (1 approximately 8) cycles. From an intention-to-treat analysis, 6 patients achieved partial responses (PR), with a response rate of 20.7% (95% CI, 6.0~35.4). The duration of objective PRs in these six were 2.3+, 2.5+, 2.9, 3.0+, 6.2 and 6.8 months, respectively. Six patients showed a stable disease, but 15 showed progression. The median time to progression was 4.2 months (95% CI, 2.8 approximately 5.5), with a median overall survival since the start of D monotherapy of 8.4 months (95% CI, 5.5 approximately 11.3). Grade 3/4 neutropenia and febrile neutropenia occurred in 12.9% of patients and 3.1% of cycles. The incidence of grade 3 or worse non-hematological toxicities were as follows; peripheral sensory neuropathy 9.7%, asthenia 3.2% and allergic reaction 2.7%.

CONCLUSION

Docetaxel, 75 mg/m(2), is active in AGC as second-line chemotherapy after failure of prior exposure to the F and P combination chemotherapy, with a favorable toxicity profile.

Microsatellite instability in gastric cancer and pre-cancerous lesions

AIM: To investigate the microsatellite instability (MSI) in cancer and pre-cancerous lesions of the stomach and its mechanisms underlying the development of gastric cancer.

METHODS: Thirty-six gastric cancer samples were obtained from patients undergoing surgery. Forty-one gastric mucosa samples with dysplasia and 51 with intestinal metaplasia (IM) were obtained from patients with chronic gastritis undergoing gastro-endoscopy. Genomic DNA was extracted from the samples. Silver staining single strand conformation polymorphis-polymerize chain reaction (SSCP-PCR) was used to screen MSI markers at 5 loci (Bat-25, Bat-26, D5S346, D17S250, and D2S123) in fresh tissues and formalin-fixed, paraffin-embedded samples and their corresponding normal gastric mucosa.

RESULTS: The abnormal shifting of the single-strand DNA (MSI) was identified in 21 out of 36 (58.3%) gastric cancers. Seven cases showed high-level MSI (two or more loci altered) and 14 showed low-level MSI (one locus altered). Gastric cancer with MSI had a tendency to be located in the distal stomach. MSI was also detected in 11 out of 41 (26.8%) dysplasia samples and in 9 of 51 (17.6%) IM samples respectively. Three cases of dysplasia and one case of IM showed high-level MSI. Eight cases of dysplasia and 8 cases of IM displayed low-level MSI. MIS in IM was found only in moderate or severe-grade IM. No association was detected between MSI and dysplasia grade.

CONCLUSION: Accumulation of MSI in dysplasia and intestinal metaplasia of gastric mucosa may be an early molecular event during gastric carcinogenesis and may contribute to the acquisition of transformed cell phenotype and the development of gastric cancer.

Microsatellite instable double primary cancers of the colorectum and stomach exhibit less favorable outcome

AIM: To ascertain the adequacy of the microsatellite instability (MSI) as a prognostic indicator by assessing MSI status of patients with double primary gastric and colorectal cancer (DPGCC).

METHODS: Sixteen patients were studied, all of whom exhibited sporadic DPGCC, and had no family history of hereditary non-polyposis colorectal cancer, according to the Amsterdam criteria. A total of 32 cancers from 16 DPGCC patients, and 216 single primary CRC, were assessed for MSI in 5 microsatellite loci, BAT25, BAT26, D2S123, D5S346, and D17S250.

RESULTS: MSI was observed in 6 (37.5%) of 16 GC and 4 (25.0%) of 16 CRC. Thirty tumors (13.9%) out of 216 single primary CRC and one tumor (16.7%) out of 6 double primary CRC were found to be microsatellite unstable. Of the 6 GC with MSI in DPGCC, 5 (31.3%) were MSI-high and one (6.3%) was MSI-low. In 5 of 16 DPGCC patients, the cancer recurred in or adjacent to the anastomosis or metastasized to the kidney or lung. The MSI-high DPGCC cases were associated with a younger age of onset (47.5 years vs 62.5 years), higher frequency of lymph node metastasis (100% vs 25%), and advanced Dukes stage (C, 100% vs 41.7%), as well as a higher frequency of recurrence or metastasis (100% vs 8.3%). Only recurrence or metastasis showed statistical significance by Fisher’s exact test.

CONCLUSION: Our data suggest that MSI may play an important role in the development of DPGCC, and that it may be used clinically as a molecular predictive marker for recurrence or late metastasis of DPGCC.

Anti-cancer effect of iNOS inhibitor and its correlation with angiogenesis in gastric cancer

AIM: To observe the anti-cancer effect of iNOS selective inhibitor (aminoguanidine, AG) and investigate the relationship between iNOS inhibitor and angiogenesis, infiltration or metastasis in MFC gastric cancer xenografts.

METHODS: Fifty athymic mice xenograft models were established by inoculating gastric cancer cell MFC subcutaneously. Twenty-four hours later, 0.9% sodium chloride solution, mitomycin, low dosage AG, high dosage AG, mitomycin and AG were administered by intraperitoneal injection respectively. Thus these mice were divided into five groups of 10 each randomly: control group, MMC group, AG_L group, AG_H group, MMC+AG_H group. Two weeks later the mice were killed, and the tumor weight, inhibitory rate were evaluated. Greiss assay was used to detect the nitric oxide levels in plasma. HE and immunohistochemistry staining were used to examine microvessel density (MVD) and the expression of iNOS, VEGF, and PCNA. Apoptosis was detected by using TUNEL assay.

RESULTS: The inhibitory rates in MMC+AG_H group and AG_H group were 52.9% and 47.1% respectively, which is significant statistically compared with that of control group (0). In treatment groups, the cell proliferation index (PI) was lower and apoptosis index was higher than those of control group. Microvessel density, iNOS, and VEGF in MMC+ AG_H group were 8.8 ± 2.6, 2.4 ± 1.1, and 2.1 ± 1.4 respectively, which is significant statistically compared with those of control group (68.3 ± 10.6, 11.3 ± 1.3, and 10.3 ± 1.6). The NO level in plasma of MMC+ AG_H and AG_H group were 12.7 ± 2.1 and 12.9 ± 2.0 μmol/L. Compared with that of control group (46.6 ± 2.3 μmol/L), the difference is statistically significant.

CONCLUSION: AG has anticancer effect on gastric cancer, and it has positive synergistic effect with chemotherapeutic drugs. It may play important inhibitory roles in angiogenesis of gastric cancer. The anticancer effect of iNOS inhibitors may include inducing cell apoptosis, suppressing cell proliferation and reducing angiogenesis.

The surgeon's expertise-outcome relationship in gastric cancer surgery

PURPOSE

The surgical caseload or duration of practice of a surgeon may influence the outcomes of gastric cancer surgery. This study aimed to clarify the surgical quality provided by specialized gastric cancer surgeons.

MATERIALS AND METHODS

The postoperative courses of 1,877 patients who underwent surgery for gastric cancer were retrospectively reviewed. For classification of the surgeon's expertise, the number of yearly resections performed by, and consecutive years of practice of, the surgeons were used. The outcome measures used were the 30-day mortality and long-term survival.

RESULTS

Surgical mortalities of patients who underwent surgery by a specialized surgeon and those by a general surgeon revealed no statistically significant difference. A significant difference in the five-year survival rates was found with surgeons with at least two consecutive years of practice compared to those with less than two years, when 50 or more cases had been conducted per year (63.9% and 59.7%; p=0.0380). In cases of four-years of consecutive practice, the five-year survival rate was significantly improved, even if only 10 cases were performed annually (64.9% and 58.3%; p=0.0023), although the best survival rate was found with surgeons that had performed 50 or more surgeries per year.

CONCLUSION

Improved survival rates, with acceptable surgical mortality, can be achieved for gastric cancer when the surgery is performed by a specialized surgeon. A specialized gastric cancer surgeon can be defined as one who has operated on more than 50 new cases per year, with 2 or more consecutive years of surgical practice.

Significance of hTERT, E-Cadherin and Catenin-b expression in stomach mucinous adenocarcinoma

AIM: To study the significance of human telomerase reverse transcriptase (hTERT), E-Cadberin (E-cad) and Catenin-b (b-cat) expression in the tissues of stomach mucinous adenocarcinoma.

METHODS: The expression of hTERT, E-cad and b-cat were detected by immunohistochemical staining and in situ hybridization in 92 cases of stomach mucinous adenocarcinomas.

RESULTS: The expression of hTERT is negative outside and positive inside of mucinous adenocarcinoma cells, and its expression in pure mucinous adenocarcinoma, papillary mucinous adenocarcinoma, signet-ring cell mucinous adenocarcinoma and mixed cell mucinous adenocarcinoma is 88.9%, 85.4%, 100.0% and 95.8% respectively. The expression ratio become higher with the malignant degree, but no significant difference was found (P>0.05). The expression of E-cad is 100.0% in both pure and papillary mucinous adenocarcinoma, but is 38.9% and 62.5% in signet-ring cell and mixed cell mucinous adenocarcinoma respectively, which showed that E-cad expression was decreased with malignant degree (P<0.01).The expression of b-cat was also decreased with malignant degree.

CONCLUSION: The positive level of hTERT, E-cad and b-cat is related to the histopathological types of stomach mucinous adenocarcinoma, and they are important in the judgement of prognosis.

Heterozygosity loss of fragile histidine triad gene in gastric cancer and precancerous lesions

AIM: To detect the loss of heterozygosity (LOH) of fragile histidine triad (FHIT) gene in gastric cancer and precancerous lesions (dysplasia and intestinal metaplasia), and to analyze its role in the carcinogenesis of gastric cancer.

METHODS: The LOH at microsatellites loci D3S1234 and D3S1300 of FHIT gene were measured in samples of gastric cancer (n = 42), dysplasia (n = 44), intestinal metaplasia (n = 51) and their corresponding normal tissues by (polymerase chain reaction) PCR.

RESULTS: The rates of LOH at D3S1234 locus were 32.4%(11/34), 28.6%(10/35) and 10%(4/40) in gastric cancer, dysplasia and intestinal metaplasia respectively, and the ones at D3S1300 locus were 33.3%(12/36) , 32.4%(11/34) and 7.7% (3/39) respectively. The LOH rates at D3S1234 and D3S1300 loci in gastric cancer and atypical hyperplasia were higher than that of intestinal metaplasia (P<0.05, P<0.01 for D3S1234 and D3S1300 respectively). No significant difference of LOH rate was found between gastric cancer and dysplasia.

CONCLUSION: The loss of heterozygosity of FHIT gene may be an early event in the tumorigenesis of gastric cancer.

Clinicopathological analysis of Borrmann type IV gastric cancer

PURPOSE

Borrmann type IV gastric cancer is often diagnosed only at an advanced stage, resulting in a prognosis poor. We performed a retrospective study of the clinical characteristics of Borrmann type IV gastric cancer and the prognostic factors affecting the survival rate in such patients.

MATERIALS AND METHODS

Of 4,063 patients with all gastric cancers, 370 (9%) with Borrmann type IV gastric cancer were analyzed.

RESULTS

The clinical characteristics of these patients included a higher incidence rate in young females, and higher rates of serosa exposure, metastasis to lymph nodes and early peritoneal dissemination. Of patients presenting with peritoneal seeding, those resected had a higher survival rate than those that were not. A univariate analysis showed that the prognostic factors affecting the survival rate following a curative resection were the location, occupied area and depth of the primary tumor, as well as the presence of lymph node metastasis and the tumor stage. A multivariate analysis indicated that the tumor location and stage were significant independent prognostic factors after a curative resection for Borrmann type IV gastric cancer.

CONCLUSION

In conclusion, the early diagnosis and treatment of patients with Borrmann type IV gastric cancer are essential for the better survival of these patients. Even in patients with advanced tumors, a noncurative palliative resection may improve the prognosis.

Loss of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) expression in gastric cancers

PURPOSE

DNA-PKcs is one of the DNA repair genes. It was recently found that hyperplasia and dysplasia of the intestinal mucosa and the production of aberrant crypt foci were developed in DNA-PKcs-null mice, and this suggests a suppressive role for DNA-PKcs in tumorigenesis.

MATERIALS AND METHODS

To investigate the possible relationship between the clinico-pathologic characteristics and the survival of gastric cancer patients, the expression status of DNA-PKcs was determined in 279 consecutive gastric cancers. Immunohistochemical analysis was performed to evaluate the expression levels of DNA-PKcs protein by using the tissue array method.

RESULTS

Out of 279 consecutive gastric cancers, 63 cases (22.6%) showed the loss of DNA-PKcs expression. The loss of DNA-PKcs expression was significantly associated with advanced cancer (p<0.001), lymphatic invasion (p=0.001), lymph node metastasis (p=0.009), and advanced pTNM stage (p=0.009). Univariate survival analysis revealed that patients with the loss of DNA-PKcs expression had significantly poorer survival than those patients with intact DNA-PKcs expression (p=0.004). Moreover, the loss of DNA-PKcs expression was identified to correlate with a lower survival in the subgroup of stage I gastric cancer patients (p=0.037).

CONCLUSION

The loss of DNA-PKcs expression was found in 23% of human gastric cancers and this was identified to significantly correlate with poor patient survival, especially for stage I gastric cancer patients.

cDNA microarray analysis of differential gene expression in gastric cancer cells sensitive and resistant to 5-fluorouracil and cisplatin

PURPOSE

Gastric cancer is one of the most prevalent cancers worldwide. 5-fluorouracil (5-FU) and cisplatin are the most commonly used drugs for the treatment of gastric cancer. However, a significant number of tumors often fail to respond to chemotherapy.

MATERIALS AND METHODS

To better understand the molecular mechanisms underlying drug resistance in gastric cancer the gene expression in gastric cancer cells, which were either sensitive or resistant to 5-FU and cisplatin, were examined using cDNA microarray analysis. To confirm the differential gene expression, as determined using the microarray, semiquantitative RT-PCR was performed on a subset of differentially expressed cDNAs.

RESULTS

69 and 45 genes, which were either up-regulated (9 and 22 genes) or down-regulated (60 and 25 genes), were identified in 5-FU- and cisplatin-resistant cells, respectively. Several genes, such as adaptor-related protein complex 1 and baculoviral IAP repeat-containing 3, were up-regulated in both drug-resistant cell types. Several genes, such as the ras homolog gene family, tropomyosin, tumor rejection antigen, protein disulfide isomerase-related protein, melanocortin 1 receptor, defensin, cyclophilin B, dual specificity phosphatase 8 and hepatocyte nuclear factor 3, were down-regulated in both drug-resistant cell types.

CONCLUSION

These findings show that cDNA microarray analysis can be used to obtain gene expression profiles that reflect the effect of anticancer drugs on gastric cancer cells. Such data may lead to the assigning of signature expression profiles of drug-resistant tumors, which may help predict responses to drugs and assist in the design of tailored therapeutic regimens to overcome drug resistance.

Prognostic significance of CD24 expression in gastric carcinoma

PURPOSE

The human CD24 antigen is a small heavily glycosylated cell surface protein, which is expressed in hematological malignancies, as well as in a large variety of solid tumors. Its expression is now known to be related to the prognosis of several kinds of tumors. This study is designed to examine the prognostic significance of CD24 in Korean gastric cancer patients.

MATERIALS AND METHODS

In the present study, we examined CD24 expression in 300 consecutive cases of gastric carcinoma by immunohistochemical staining using the tissue-array method. We also investigated the clinicopathological profiles related to CD24 expression.

RESULTS

One hundred and three cases out of 300 (34.3%) showed the positive expression of CD24. The altered expression of CD24 was significantly associated with differentiated cancer (p=0.003), the intestinal subtype according to the Lauren classification (p<0.001), the advanced stage cancer (p=0.027), with lymphatic invasion (p=0.038) and with vascular invasion (p=0.006). The survival analysis revealed that the patients with CD24 positive expression showed significantly poorer survival than those without CD24 expression. Moreover, a combined evaluation revealed that PTEN+/CD24- cases showed the best survival compared to other groups (p=0.01).

CONCLUSION

Positive CD24 expression occurs in a subset of gastric carcinomas and it correlates significantly with lymphatic invasion, blood vessel invasion and poor survival.

Treatment of cancerous ascites and radical gastrectomy with intraperitoneal hyperthermic double-distilled water and cis-diaminodichloro-platinum perfusion

AIM: To study the therapeutic effect of intraperitoneal hyperthermic double-distilled water and cis-diaminodichloro-platinum (DDP) perfusion for cancerous ascites and radical gastrectomy.

METHODS: LACA mice were injected peritoneally with H₂₂ cancer cells (2 × 10⁷ tumor cells). Five days later, the mice received treatments with either intraperitoneal perfusion of 37 °C isotonic fluid (group I), or 43 °C simple hyperthermic double-distilled water (group II), isotonic fluid (group III), DDP (group IV) or a combination of the hyperthermic double-distilled water with DDP (group V). A clinical experiment with intraperitoneal hyperthermic double-distilled water perfusion with DDP was carried out from September 1991 through September 1993 with 32 advanced gastric cancer patients who had undergone radical gastrectomy.

RESULTS: In comparison with the untreated control group of cancer cell-bearing LACA mice, the mice in all treatment groups showed near complete obliteration of cancer cells in the peritoneal cavity, markedly reduced ascites, prolonged survival times, and reduced growth of peritoneal cancerous nodes. In the clinical experiment, all 32 patients with advanced carcinoma had achieved satisfactory results at the 1-year follow-up, but had unsatisfactory results at the 2-year follow-up.

CONCLUSION: The intraperitoneal hyperthermic double-distilled water perfusion with DDP inhibited the occurrence of ascites in LACA mice bearing cancer cells, and prolonged the lifetime of patients with gastric cancer who had undergone radical gastrectomy.

Multicenter randomized study on Me-CCNU, 5-FU and ADM vs ACNU, 5-FU and ADM for treatment of advanced gastric cancer

AIM: To compare the efficacy of a combined chemotherapy regimen of 5-fluouracil (5-FU) and adriamycin (ADM) with nimustine hydrochloride (ACNU; brand name Nidran), a new nitrosourea agent, or with methyl-CCNU for advanced gastric cancer.

METHODS: One-hundred-and-three cases of advanced gastric cancer were randomly allocated into Group A (Me-CCNU, 5-FU and ADM combination) and Group B (ACNU, 5-FU and ADM combination). The quality of life (QOL) questionnaire, composed of 11 ordinal categorical items, was used to collect data from these patients.

RESULTS: Group A had no case of complete remission (CR) or partial remission (PR), while Group B had no CR but 8 PR (8/46 cases), for a response rate of 0% in Group A and 17.4% in Group B. The median survival time in Group A was 108 d and in Group B was 112 d. Both groups tolerated the treatment well and there were no serious adverse effects. QOL evaluations showed better psychological and physical feelings of tiredness for Group B than for Group A, and scores based on facial scaling showed a more pleasant inclination for the former.

CONCLUSION: ACNU combination is superior to the Me-CCNU combination for advanced gastric cancer patients.

Clinical significance of CA19-9 in diagnosis of digestive tract tumors

AIM: To evaluate the clinical value of CA19-9 in diagnosing and differentiating gastrointestinal tumors and in monitoring patients treated surgically.

METHODS: Patients with gastric cancer (n = 70), colorectal cancer (n = 90), pancreatic cancer (n = 7), esophageal cancer (n = 10) and benign disorders (n = 30), and normal adults (n = 111; used as healthy controls), were studied. Fasting blood samples were obtained from each study participant. The serum CA19-9 concentration was measured with radioimmunoassay.

RESULTS: The mean CA19-9 level was significantly higher in patients with gastric cancer (170.69 ± 91.45 kU/L) and patients with colorectal cancer (87.21 ± 39.55 kU/L) than in the healthy controls (11.254 ± 6.00 kU/L). Compared with the healthy controls, the CA19-9 level was also much higher in patients with pancreatic cancer (1266.58 ± 521.31 kU/L) (P < 0.01). However, the CA19-9 concentrations in patients with non-recurrent gastric cancer (12.63 ± 3.62 kU/L), colorectal cancer (14.14 ± 3.26 kU/L) and benign disorders (14.23 ± 2.60 kU/L) were statistically similar to those in the healthy controls (P > 0.05). The demarcation value of CA19-9 between negative and positive was < 31.0 kU/L. The sensitivity of CA19-9 for gastric, colorectal, pancreatic and esophageal cancers and for gastrointestinal benign disorders was 47.3%, 50.0%, 83.3%, 20.0% and 0%, respectively. The specificity of CA19-9 for digestive system malignant diseases was 100% for all.

Clinical and experimental studies on stomach carcinoma treated with Yangwei Kangliu granules

AIM: To study the anti-cancer mechanism of Yangwei Kangliu (YWKL) granules from the view point of red blood cell (RBC) immunity and to investigate the relationship between RBC immunity and T lymphocyte immunity.

METHODS: Fifty patients with advanced gastric carcinoma were treated with a combination of YWKL granules and chemotherapy. Venous blood samples were obtained before treatment and after one course of treatment. The rosette rate of c-3b-receptor (RBC-C-3bRR), tumor and red cell (RRTR) and RBC immune complex (RBC-ICR) were measured under microscopy by counting the rosettes formed by sensitized or unsensitized yeast adherence. The T lymphocyte subset was observed by the method of APAAP. Control patients were treated with chemotherapy alone (n = 20). In addition, mouse tumor studies were performed to investigate the dynamic changes of RBC-C-3bRR, RRTR and RBC-ICR in response to treatment with YWKL granules (n = 30). Mice treated with chemotherapy alone (n = 30) or water alone (n = 30) were used as controls.

RESULTS: The clinical therapeutic effect of combination treatment with YWKL granules and chemotherapy (i.e. the treatment group) was markedly superior to that of chemotherapy alone (i.e. the control group) (P < 0.01). In the treatment group, the rosette rates of RBC-C-3bRR and of RRTR were significantly increased (P < 0.01) after treatment, the rate of RBC-ICR was markedly decreased (P < 0.01), and the ratio of CD4 to CD8 was obviously elevated (P < 0.01). Moreover, CD8 was much lower (P < 0.01) and the ratio of CD4 to CD8 was much higher (P < 0.01) than that in the control group. The RRTR rate was positively correlated with the ratio of CD4 to CD8. In mice, on day 9 of bearing cancer, the tumor weight in the group treated with YWKL granules alone was much lower than that of the tumors in the control mice groups; in addition, the YWKL treated mice showed higher RBC immune function than the mice of the two control groups. On day 13 of bearing cancer, however, the differences in both tumor weight and RBC immune function had disappeared.

CONCLUSION: The anti-cancer mechanism of YWKL granules may involve enhancement of RBC immunity and of T lymphocyte immune function, which is supported by the finding of RBC immune function being correlated with T lymphocyte immune function.

Loss of heterozygosity and mRNA expression at deleted in colorectal cancer gene locus in gastric cancer

AIM: To assess the effects of the deleted in colorectal cancer (DCC) gene changes on the development and progression of gastric cancer.

METHODS: The loss of heterozygosity (LOH) and mRNA expression DCC gastric cancer using a PCR-based detection method.

RESULTS: LOH was found in 35.3% (18/51) of the specimens, and the LOH was more frequently detected in tumors from patients with stage III or IV cancer (50.5%) than those in stages I or II (14.3%) (P < 0.05). The occurrence of LOH was not found to correlate with the histological type, tumor size, invasion depth and lymph node metastasis of gastric cancer. The mRNA expression of the DCC gene was studied in 26 of the 51 cases, of which LOE was found in 30.8% (8/26). LOE was not significantly correlated to LOH or other clinicopathological parameters.

CONCLUSION: LOH and LOE of DCC gene are frequently encountered in gastric cancer, and the LOH of DCC gene is a late event associated with progression of gastric cancer.

Effects of Linomide on growth and metastasis of implanted human gastric cancer in nude mice

AIM: To elucidate the effect of angiogenesis inhibitor, Linomide, on tumor growth and metastasis in nude mice implanted with human gastric cancer.

METHODS: A metastatic model of gastric cancer was established using orthotopic implantation of histologically intact tumor tissues into the gastric wall of nude mice. Linomide (0, 80, 160 mg·kg^-1) was given p.o. every day after the implantation, and the mice were sacrificed after 10 wk to detect tumor size and metastasis. The microvessel counts were measured by immunohistochemical staining using a monoclonal antibody against Human Factor VIII related antigen.

RESULTS: Linomide treatment significantly decreased the size of the implanted tumors (control group: 1.36 ± 0.81 cm³vs Linomide treated group: 0.84 ± 0.51 cm³ and 0.62 ± 0.35 cm³, P < 0.05 and 0.01, respectively). Additionally, an antimetastatic effect of Linomide was clearly demonstrated in a dose dependent manner: mice given 80 mg·kg^-1 Linomide developed liver metastasis in 4 of 10 cases, mice given 160 mg/kg developed metastasis in only 1 of 10 mice, while it developed in 19 of 28 mice of the control group (P < 0.05 and 0.01, respectively). The number of metastatic foci was also significantly less in the treated group. Furthermore, the microvessel counts in tumors of treated mice was reduced by 33%-42% as compared with the control tumors (P < 0.01).

CONCLUSION: Linomide has a strong inhibitory activity against in vivo tumor growth and metastasis of gastric cancer, effectively suppressing the growth of the primary tumor, preventing liver metastasis, and attenuating the rate of neovascularization.

Preliminary study on the loss of heterozygosity at 17p13 in gastric and colorectal cancers

AIM: To evaluate the role of p53 in the development and progression of colorectal cancer and gastric carcinoma by analyzing the loss of heterozygosity (LOH) at 17p13.1 and 17p13.3.

METHODS: LOH at the p53 gene locus and 17p13.3 were examined in 22 cases of gastric carcinoma and 14 cases of colorectal cancer by Southern blot analysis.

RESULTS: Of the 22 gastrocarcinoma cases, 12 (54%) were heterozygous and LOH was detected in 6 (50%) of the 12 informative cases. In the 14 colorectal cancer cases, 10 (71%) were heterozygous, and LOH was detected in 6 (60%) of the 10 informative cases.

CONCLUSION: LOH at the p53 gene locus is a frequent event in multiple step carcinogenesis progression. The high frequency of LOH at 17p13.3 suggests that there may be another tumor suppresser gene in that chromosome region.

Clinical significance of PCR in Helicobacter pylori DNA detection in human gastric disorders

AIM: To investigate the clinical significance of the PCR assay in the diagnosis of gastric Helicobacter pylori (Hp) infection.

METHODS: Hp infection in gastric antral biopsied specimens was identified by using the polymerase chain reaction (PCR) to amplify the specific Hp urease gene fragments (PCR-Hp-DNA) in 154 patients with gastrointestinal disorders. Hp urease gene oligonucleotide primers specific for Hp (16s rRNA) were used. Urease test and enzyme-linked immunosorbent assay (ELISA) for anti Hp-IgG serum were also used as controls.

RESULTS: PCR-Hp-DNA was detected in 140 (91%) of the 154 patients, where patients 114 and 125 were found infected with Hp by urease test and ELISA Hp IgG, respectively. There was a marked difference in the Hp-positive rate between the PCR-Hp-DNA and the urease test or ELISA-Hp-IgG (P < 0.05). The Hp infection rate increased with age, although a minority of infected people developed signs and symptoms of gastric disorders. Hp infection is closely related to adenocarcinoma in both the gastric antrum as well as the down body of the stomach.

CONCLUSION: PCR is a sensitive and specific method for the detection of Hp in human gastric tissues. Detection of Hp DNA in vivo using this approach might improve the clinical diagnosis and epidemiological research related to H. pylori infection.

Morphological analysis of lymph vessels and capillaries in gastric carcinoma

AIM: To investigate the morphology of lymph vessel capillaries in both human gastric carcinomas and their peritumoral tissues, as well as the relation of this morphology to lymphatic metastasis.

METHODS: The morphology and fine distribution of both lymph vessels and capillaries in and around the primary foci of gastric carcinoma were studied using the 5′Nase Alpase double staining method. The total amount of opened vessels and the opening rate of lymph vessels and capillaries were counted using a light microscope (100 × magnification), and the maximal luminal area, perimeter and diameter were measured using an image analysis technique.

RESULTS: Lymph vessels and capillaries displayed strong 5′Nase-positive staining (brown and dark brown), while blood vessels and capillaries revealed significant Alpase activity (blue). There were many lymph vessels, capillaries and solid strip-like tissues found in the gastric carcinoma samples analyzed. The total amount of lymphatics in the metastatic group (gastric carcinoma vs peritumoral tissue) and non-metastatic group was 26.9 ± 14.2 vs 10.4 ± 4.0, 11.4 ± 3.4 and 9.7 ± 3.2, P < 0.01, respectively. Their opening rates were 21.2 vs 47.5 and 40.4 vs 46.0, P < 0.01, respectively. Their maximal luminal areas were 1502.98 ± 1236.91 vs 5526.80 ± 4853.42; 1918.14 ± 2299.24 vs 3836.16 ± 3549.16; 5526.80 ± 4853.42 vs 3836.16 ± 3549.16, P < 0.05, their perimeters were 220.33 ± 130.25 vs 441.43 ± 276.51; 241.79 ± 171.13 vs 333.80 ± 199.66; 441.43 ± 276.51 vs 333.80 ± 199.60, P < 0.05, and their diameters were 28.80 ± 14.98 vs 59.39 ± 28.53; 25.37 ± 15.79 vs 46.22 ± 20.85; 59.39 ± 28.53 vs 46.22 ± 20.85, P < 0.05, respectively. In summary, the lymphatics found in gastric carcinoma samples from the metastatic group were significantly lower than those of the other groups.

CONCLUSION: There are newly formed lymph capillaries found in gastric carcinoma. Dilation of lymph capillaries may be related to edema found in peritumoral connective tissues. The observed lymph node metastases from gastric carcinoma occur through mature lymph capillaries that invade in and around primary gastric carcinoma foci.

Studies on the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer

AIM: To study the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer.

METHODS: The point mutations at codon 12 and 61 of c-Ha-ras, at codon 12 and 13 of K-ras, and at codon 12 of N-ras were studied with PCR-RFLP in 88 formalin fixed and paraffin embedded specimens of gastric cancer.

RESULTS: It was found that the overall rate of point mutation of ras oncogenes was 18.2% and the positivity of the point mutation of ras oncogenes was related to the cancerous invasion of the serosa, the status of lymph node metastasis, the stage of cancer and the survival time after surgery.

CONCLUSION: The findings suggest that the determination of point mutations of ras oncogenes can be used to determine the prognosis of patients with gastric cancer.