Recurrence following curative resection for gastric carcinoma

BACKGROUND

The diagnosis and treatment of recurrent gastric cancer remains difficult. The aim of this study was to determine the risk factors for recurrence of gastric cancer and the prognosis for these patients.

METHODS

Of 2328 patients who underwent curative resection for gastric cancer from 1987 to 1995, 508 whose recurrence was confirmed by clinical examination or reoperation were studied retrospectively. The risk factors that determined the recurrence patterns and timing were investigated by univariate and multivariate analysis.

RESULTS

The mean time to recurrence was 21.8 months and peritoneal recurrence was the most frequent (45.9 per cent). Logistic regression analysis showed that serosal invasion and lymph node metastasis were risk factors for all recurrence patterns and early recurrence (at 24 months or less). In addition, independent risk factors involved in each recurrence pattern included younger age, infiltrative or diffuse type, undifferentiated tumour and total gastrectomy for peritoneal recurrence; older age and larger tumour size for disseminated, haematogenous recurrence; and older age, larger tumour size, infiltrative or diffuse type, proximally located tumour and subtotal gastrectomy for locoregional recurrence. Other risk factors for early recurrence were infiltrative or diffuse type and total gastrectomy. Reoperation for cure was possible in only 19 patients and the mean survival time after conservative treatment or palliative operation was less than 12 months.

CONCLUSION

The risk factors for each recurrence pattern and timing of gastric cancer can be predicted by the clinicopathological features of the primary tumour. Since the results of treatment remain dismal, studies of perioperative adjuvant therapy in an attempt to reduce recurrence are warranted.

Clinical characteristics of Peutz-Jeghers syndrome in Korean polyposis patients

Peutz-Jeghers syndrome is an autosomal dominant inherited disorder characterized by hamartomatous polyps in the small bowel and mucocutaneous pigmentation. Patients with Peutz-Jeghers syndrome often present as surgical emergencies with complications of the polyps, such as intussusception, bowel obstruction, and bleeding. Recently an increased risk of malignancies has also been reported. This study was initiated to determine the clinical features of Peutz-Jeghers syndrome in Korean patients, with special attention to the development of malignancies. Thirty patients with Peutz-Jeghers syndrome were investigated; their median age was 23.5 years, and symptoms appeared at a median age of 12.5 years. Family history was positive in one-half of cases, and mucocutaneous pigmentation was observed in almost all patients (93%). The jejunoileum was the most frequent site of the polyps, and there were generally 10-100 polyps. Multiple laparotomies were performed in a substantial portion of the patients, due mainly to polyp-induced bowel obstruction, and the surgical interventions were begun at a relatively young age (average 21.4 years). Four cases of small-bowel cancer and one case of breast cancer were detected in probands, at a relatively young age (mean 36 years). Cancers of the small bowel, stomach, colon, breast and cervix were diagnosed in the first relatives of the probands. Close follow-up from an early age should thus be performed in patients with Peutz-Jeghers syndrome as they are at high risk of surgical emergency and development of malignancy.

Assessment of biomarkers in paired primary and recurrent colorectal adenocarcinomas

PURPOSE

Recurrent colorectal cancers respond poorly to anticancer treatment including radiotherapy. To better understand the biological characteristics of the recurrent colorectal tumor, we investigated various biomarkers regulating cell proliferation and cell loss in paired primary and recurrent colorectal tumor specimens within each individual.

METHODS AND MATERIALS

From a total of 11 colorectal adenocarcinoma patients, 22 specimens of paired primary and recurrent tumors were obtained for analysis. Apoptosis was evaluated by TUNEL labeling of apoptotic DNA fragmentation. Other biomarkers including proliferating cell nuclear antigen (PCNA), p53, WAF1, p34cdc2, and cyclins B1 and D1 were analyzed by immunohistochemical stains.

RESULTS

PCNA index (PCNAI) showed an increase in 6 and a decrease in 5 recurrent tumors compared to primary tumors. Median PCNAI in primary and recurrent tumors were 33.5 and 48.3, respectively (p = 0.16). In contrast, the apoptotic index (AI) decreased in 9 of 11 recurrent tumors compared to primary tumors. Median AI decreased from 4.3 in primary tumors to 1.4 in recurrent tumors (p = 0.04). The p53 expression increased in more than half of recurrent tumors compared to primary tumors. Mean staining score increased from 0.7 in primary tumors to 1.2 in recurrent tumors (p = 0.059). WAF1 and cyclin B1 did not show significant change. In contrast, both cyclin D1 and p34cdc2 increased significantly in recurrent tumors. These two biomarkers showed increased expression in 8 (cyclin D1) and 7 (p34cdc2) recurrent tumors, respectively, compared to their primary counterparts. Mean staining scores of both biomarkers in recurrent tumors increased by more than twofold compared to those in primary tumors and these differences were statistically significant (cyclin D1, p = 0.007; p34cdc2, p = 0.008).

CONCLUSION

This study showed significantly decreased apoptosis in recurrent colorectal tumors compared to their primary counterparts. The underlying regulatory mechanisms included increased expression of p53 and altered cell cycle regulators such as increased cyclin D1 and p34cdc2. With further study, it may be used for developing a new therapeutic strategy for the treatment of recurrent colorectal cancer.

Changes of telomerase and telomere lengths in paired normal and cancer tissues of breast

To attain the immortal phenotype, cancer cells must overcome the mitotic clock. Telomerase activity has been identified to be activated in malignant tumors including breast cancer. Telomerase activity was evaluated in 71 breast cancer tissues and paired normal tissues with the TRAP (telomerase repeat amplification protocol) assay. Telomerase activity was calculated and translated into arbitrary units by computer-assisted densitometry with the control of telomerase activity in the 293 control cell line. In 59 paired breast tissues with telomerase activity, terminal restriction fragment (TRF) lengths were measured using Southern blotting. Relative inhibition (RI), the ratio of inhibited telomerase activity in each tumor tissue compared to that of the 293 control cell line after pre-treatment with 150 microg/ml of RNAse A, was measured. Sixty-three of 71 cancer tissues showed telomerase activity (88.7%) with 75.3+/-17.9 units in densitometry, while no telomerase activity was detected in their paired normal tissues. Telomerase activity was correlated to node metastasis (p=0.02) and stage (p=0.005), but not to tumor size or the hormonal receptor status. TRF lengths were 11. 0+/-4.7 kb in 59 tumor tissues and 11.7+/-2.2 kb in paired normal tissues. TRF lengths did not correlate to any of the clinical parameters. However changes of TRF lengths in tumor tissues compared to those of normal tissues correlated to telomerase activity. RI in the tumor tissues was proportional to telomerase activity without RNAse A pre-treatment. In breast cancer, telomerase activity was specific to tumor tissues and increased with tumor progression. Telomerase activity and changes in TRF lengths can be used as guidelines in detecting candidates for the telomerase inhibitor.

Modulation of biological phenotypes for tumor growth and metastasis by target-specific biological inhibitors in gastric cancer

For tumor progression, a cascade of linked sequential biological events is essential. We tried to test whether biological therapy can modulate specific biological phenotypes and increase the anti-tumor effect when combined with chemotherapy. Five human gastric cancer cell lines (YCC-1, YCC-2, YCC-3, YCC-7, AGS) were used in these studies. Pentosan polysulfate (PPS) as a heparin-binding growth factor inhibitor, Tranexamic acid as a plasmin inhibitor, Lovastatin as an adhesion inhibitor and Adriamycin as a chemotherapeutic agent were selected. The effects of each drug on colony formation and tumor cell proliferation were evaluated by soft agar assay and cell proliferation assay, respectively to test direct anti-tumor effect. The expression of uPA, PAI-1 was determined by ELISA, while MMPs activity was evaluated by zymography. PPS suppressed the colony-forming activity as much as Adriamycin did, but it showed only cytostatic effects in cell proliferation assay. Migration capacity using Boyden chamber assay was more closely correlated with adhesive capacity than uPA or MMP-2 expression. The motility inhibitory effect of Tranexamic acid was observed in the YCC-7 cell line, which expressed all the required biological phenotypes for migration. In AGS, with high cell motility and adhesiveness, the adhesion was inhibited by Lovastatin and most of the inhibitory effect was recovered by Mevalonate. When PPS was combined with Adriamycin on the Adriamycin-resistant, midkine (MK) gene expressing YCC-7 cell line, the growth inhibition rate increased up to 84%, while that for a single treatment of PPS or Adriamycin was 40% and 22%, respectively (p=0.001). When we combined Tranexamic acid and Adriamycin, we observed the synergistic effect in YCC-3 and YCC-7, while no combined effect was found in YCC-1. The combination of Lovastatin and Adriamycin did not show any combined effects in any of the cell lines. In conclusion, a synergistic anti-proliferative effect (chemo-sensitization) with combined chemo-biotherapy was found in cancer cells with specific biological target, MK. The anti-motility effect was the greatest when the gastric cancer cells expressed all the specific biological phenotypes.

Prognostic significance of CD44 and nm23 expression in patients with stage II and stage IIIA gastric carcinoma

BACKGROUND AND OBJECTIVES

Predicting the prognosis in gastric carcinoma patients with intermediate stages is difficult. We investigated the prognostic impacts of CD44 and nm23 expression in a homogeneous group of patients with stage II and IIIA gastric carcinoma who had undergone curative resections.

METHODS

A total of 261 paraffin-embedded gastric carcinomas were stained with the monoclonal antibodies CD44 and nm23 using the labeled streptovidin biotin method.

RESULTS

The expression of CD44 and nm23 was detected, respectively, in 31.0% (81/261) and 70.1% (183/261) of all tumors. There was no correlation between CD44 expression and clinicopathological variables. However, nm23 was more frequently expressed in older patients with differentiated adenocarcinoma. A significant difference in 5-year survival rates was found between patients with CD44-positive (43.2%) and CD44-negative tumors (63.4%), (P = 0.0018). However, there was no significant difference in 5-year survival rates between patients with nm23-positive (54.7%) and nm23-negative tumors (62.7%) (P = 0.2734).

CONCLUSIONS

CD44 expression was a significant adverse prognostic factor in gastric carcinoma and may be a predictor of metastatic potential of the primary tumor. By contrast, immunohistochemical detection of nm23 expression was not a predictor of outcome of patients with gastric carcinoma.

Comparative study of transrectal ultrasonography, pelvic computerized tomography, and magnetic resonance imaging in preoperative staging of rectal cancer

PURPOSE

The preoperative assessment of rectal cancer wall invasion and regional lymph node metastasis is essential for the planning of optimal therapy. This study was done to determine the accuracy and clinical usefulness of transrectal ultrasonography, pelvic computed tomography, and magnetic resonance imaging in preoperative staging.

METHODS

A total of 89 patients with rectal cancer were examined with transrectal ultrasonography (n = 89), pelvic computed tomography (n = 69), and magnetic resonance imaging with endorectal coil (n = 73). The results obtained by these diagnostic modalities were compared with the histopathologic staging of specimens.

RESULTS

In staging depth of invasion, the overall accuracy was 81.1 percent (72/89) by transrectal ultrasonography, 65.2 percent (45/ 69) by computed tomography, and 81 percent (59/73) by magnetic resonance imaging. Overstaging was 10 percent (9/89) by transrectal ultrasonography, 17.4 percent (12/69) by computed tomography, and 11 percent (8/73) by magnetic resonance imaging; and understaging was 8 of 89 (8.9 percent) by transrectal ultrasonography, 12 of 69 (17.4 percent) by computed tomography, and 6 of 73 (8 percent) by magnetic resonance imaging. In staging lymph node metastasis, the overall accuracy rate was 54 of 85 (63.5 percent) in transrectal ultrasonography, 39 of 69 (56.5 percent) in computed tomography, and 46 of 73 (63 percent) in magnetic resonance imaging. The sensitivity was 24 of 45 (53.3 percent) in transrectal ultrasonography, 14 of 25 (56 percent) in computed tomography, and 33 of 42 (78.5 percent) in magnetic resonance imaging; and specificity was 30 of 40 (75.0 percent) in transrectal ultrasonography, 25 of 44 (56.8 percent) in computed tomography, and 13 of 31 (41.9 percent) in magnetic resonance imaging. The accuracy in detection of positive lateral pelvic lymph nodes under magnetic resonance imaging (n = 8) was 12.5 percent. The accuracy in detection of posterior vaginal wall invasion was 100 percent in transrectal ultrasonography (n = 7) and 100 percent in magnetic resonance imaging (n = 3), but 28.5 percent in computed tomography (n = 7).

CONCLUSIONS

Both transrectal ultrasonography and magnetic resonance imaging with endorectal coil exhibited similar accuracy and were superior to conventional computed tomography in preoperative assessment of depth of invasion and adjacent organ invasion. Because transrectal ultrasonography is a safer and more cost-effective modality than magnetic resonance imaging, transrectal ultrasonography is an appropriate method for preoperative staging of rectal cancer. Further efforts will be needed to provide a better staging of lymph node involvement.

Prognostic significance of CD44 and nm23 expression in patients with stage II and stage IIIA gastric carcinoma

BACKGROUND AND OBJECTIVES

Predicting the prognosis in gastric carcinoma patients with intermediate stages is difficult. We investigated the prognostic impacts of CD44 and nm23 expression in a homogeneous group of patients with stage II and IIIA gastric carcinoma who had undergone curative resections.

METHODS

A total of 261 paraffin-embedded gastric carcinomas were stained with the monoclonal antibodies CD44 and nm23 using the labeled streptovidin biotin method.

RESULTS

The expression of CD44 and nm23 was detected, respectively, in 31.0% (81/261) and 70.1% (183/261) of all tumors. There was no correlation between CD44 expression and clinicopathological variables. However, nm23 was more frequently expressed in older patients with differentiated adenocarcinoma. A significant difference in 5-year survival rates was found between patients with CD44-positive (43.2%) and CD44-negative tumors (63.4%), (P = 0.0018). However, there was no significant difference in 5-year survival rates between patients with nm23-positive (54.7%) and nm23-negative tumors (62.7%) (P = 0.2734).

CONCLUSIONS

CD44 expression was a significant adverse prognostic factor in gastric carcinoma and may be a predictor of metastatic potential of the primary tumor. By contrast, immunohistochemical detection of nm23 expression was not a predictor of outcome of patients with gastric carcinoma.

Comparison of prognostic significance of nodal staging between old (4th edition) and new (5th edition) UICC TNM classification for gastric carcinoma. International Union Against Cancer

The description of nodal staging for gastric cancer was changed in the new fifth edition of the International Union Against Cancer (UICC) TNM classification from the anatomic sites of metastatic lymph nodes to the number of metastatic lymph nodes, as pN1 is metastasis in 1 to 6 lymph nodes, pN2 is in 7 to 15 lymph nodes, and pN3 is in 16 or more lymph nodes. The purpose of this study was to investigate the prognostic significance of the new staging system based on the number of metastatic lymph nodes compared to the old staging system by anatomic site. From 1987 to 1994 a total of 2108 patients who underwent potentially curative resections with D2 or D3 lymph node dissection and with 15 or more lymph nodes retrieved were studied retrospectively. Lymph node metastases were found in 1018 patients (48.3%). A mean of 37.9 lymph nodes were retrieved per patient, and a mean of 7.2 lymph nodes were invaded by tumor cells. We found that the new nodal staging based on the number of metastatic lymph nodes closely correlated with the depth of cancer invasion and with the old nodal staging based on the anatomic site of the metastatic nodes, with statistical significance. The 5-year survival rates after gastrectomy decreased significantly by increasing the extent of the pN classification in both nodal staging methods. In a subgroup analysis of survivals between the old and new nodal staging, the new classification showed more homogeneous survival at the same stage than the old one. With a multivariate analysis of prognostic factors, including the old and new nodal staging, the depth of invasion and the new nodal stage were the most significant prognostic factors, followed by the old nodal stage. Our data suggested that the new nodal staging based on the number of metastatic lymph nodes is not only a reliable and objective method for nodal classification, but it is also a significant prognostic determinant for gastric cancer that can be used in practice.

Clinicopathologic characteristics of mucinous gastric adenocarcinoma

There has been considerable controversy over the prognosis of mucinous gastric adenocarcinoma (MGC). In this study we analyzed the clinicopathologic differences between MGC and non-mucinous gastric carcinoma (NMGC). In addition, the relationship between mucin content and other clinicopathologic variables, including prognosis in MGC, was also investigated. We reviewed 2118 patients with pathologically-confirmed gastric cancer who underwent gastrectomy at the Department of Surgery, Yonsei University College of Medicine, during the period between Jan. 1987 and Dec. 1993. Among them, 130 patients had gastric carcinoma with extracellular mucin (MGC) and 1988 patients had gastric carcinoma without extracellular mucin (NMGC). We placed the MGC patients into two groups according to mucin content: mucin content involving over 50% of the tumor (dominant type, n = 94) and mucin content involving less than 50% of the tumor area (partial type, n = 36). The results were as follows: MGC was more common in males than NMGC. The size of the tumor in MGC (mean 5.3 cm) was larger than that of NMGC (mean 4.4 cm). The patients with MGC had a higher incidence of Borrmann type IV (MGC: 16.1%, NMGC: 9.9%), more frequent serosal invasion (MGC: 75.4%, NMGC: 48.6%), lymph-node metastasis (MGC: 75.4%, NMGC: 50.7%), and peritoneal metastasis (MGC: 10.0%, NMGC: 3.5%) than patients with NMGC. The patients with MGC were more advanced in stage at the time of diagnosis and had a worse overall 10-year survival rate (44.9%) than patients with NMGC (54.7%). However, the 10-year survival rate according to the stage of MGC was similar to that of NMGC. There were no significant differences between the mucin content and other pathologic variables, including prognosis, i.e. similar biologic behavior between dominant type MGC and partial type MGC. In conclusion, we suggest that MGC was more frequently diagnosed in advanced stage than NMGC with a poorer prognosis and that it is reasonable to consider the carcinoma with mucin content involving more than 30% of the tumor area as MGC.

Effects of interleukin-2 transduction on the human hepatoma cell lines using retroviral vector

Gene therapy, using cytokine gene transduction, aims to increase the antigenicity of tumor cells, and to activate the immune effector cells, and thereby inducing tumor regression. With regards to in vitro sensitivity to peripheral blood monocytes and in vivo tumorigenic activity we compared the differences between parent hepatoma cell lines and interleukin-2 (IL-2) transduced hepatoma cell lines using N2A/IL-2 and LNC/IL-2 retrovirus. IL-2 secretion was 186 pg/10(6) cells/24 h in SK-Hep1 cell line and 147 pg/106 cells/24 h in Hep-3B cell line with N2A/IL-2 retroviral vector and was 55,000 pg/10(6) cells/24 h in Hep-3B cell line with LNC/IL-2 retroviral vector. in vitro sensitivity to peripheral blood monocytes was increased by 163.8-254% in IL-2 transduced hepatoma cell lines (Hep-3B/LNC/IL-2, Hep-G2/LNC/IL-2) compared to those of the parent cell lines. The tumor was formed in 1 of 3 BALB/c mice and all 3 nude mice with the injection of 1x107 cells. Simultaneous injection of 1x10(7) cells of the parent cell line (Hep-3B) into the right flank and IL-2 transduced cell line (Hep-3B/LNC/IL-2) into the left flank of the three BALB/c mice and of 5x10(5) cells for the three nude mice resulted in a complete regression of the IL-2 modified tumor cell line (Hep-3B/LNC/IL-2) in 3 weeks and the parent cell line (Hep-3B) in 5 weeks. After injection of 1x10(7) cells into five other nude mice, the tumor of the IL-2 transduced hepatoma cells (Hep-3B/LNC/IL-2) gradually disappeared, however, the tumor of the parent hepatoma cell line initially decreased and then gradually regrew 20 days later. In conclusion, IL-2 transduced hepatoma cell lines secreting IL-2 became more sensitive to peripheral blood monocytes. IL-2 secretion by LNC/IL-2 retrovirus from the hepatoma cell lines was more prominent compared with that by N2A/IL-2 retrovirus. IL-2 transduction into the hepatoma cells resulted in increased antigenicity to the tumors formed by IL-2 transduced hepatoma cell line and parent cell line, which leads the regression of the tumors. However, the higher the tumor burden, the less efficient tumor regression by IL-2 transduction into the hepatoma cell line in nude mice was observed.

Effects of interleukin-2 transduction on the human hepatoma cell lines using retroviral vector

Gene therapy, using cytokine gene transduction, aims to increase the antigenicity of tumor cells, and to activate the immune effector cells, and thereby inducing tumor regression. With regards to in vitro sensitivity to peripheral blood monocytes and in vivo tumorigenic activity we compared the differences between parent hepatoma cell lines and interleukin-2 (IL-2) transduced hepatoma cell lines using N2A/IL-2 and LNC/IL-2 retrovirus. IL-2 secretion was 186 pg/10(6) cells/24 h in SK-Hep1 cell line and 147 pg/106 cells/24 h in Hep-3B cell line with N2A/IL-2 retroviral vector and was 55,000 pg/10(6) cells/24 h in Hep-3B cell line with LNC/IL-2 retroviral vector. in vitro sensitivity to peripheral blood monocytes was increased by 163.8-254% in IL-2 transduced hepatoma cell lines (Hep-3B/LNC/IL-2, Hep-G2/LNC/IL-2) compared to those of the parent cell lines. The tumor was formed in 1 of 3 BALB/c mice and all 3 nude mice with the injection of 1x107 cells. Simultaneous injection of 1x10(7) cells of the parent cell line (Hep-3B) into the right flank and IL-2 transduced cell line (Hep-3B/LNC/IL-2) into the left flank of the three BALB/c mice and of 5x10(5) cells for the three nude mice resulted in a complete regression of the IL-2 modified tumor cell line (Hep-3B/LNC/IL-2) in 3 weeks and the parent cell line (Hep-3B) in 5 weeks. After injection of 1x10(7) cells into five other nude mice, the tumor of the IL-2 transduced hepatoma cells (Hep-3B/LNC/IL-2) gradually disappeared, however, the tumor of the parent hepatoma cell line initially decreased and then gradually regrew 20 days later. In conclusion, IL-2 transduced hepatoma cell lines secreting IL-2 became more sensitive to peripheral blood monocytes. IL-2 secretion by LNC/IL-2 retrovirus from the hepatoma cell lines was more prominent compared with that by N2A/IL-2 retrovirus. IL-2 transduction into the hepatoma cells resulted in increased antigenicity to the tumors formed by IL-2 transduced hepatoma cell line and parent cell line, which leads the regression of the tumors. However, the higher the tumor burden, the less efficient tumor regression by IL-2 transduction into the hepatoma cell line in nude mice was observed.

An unusual case of gastric carcinoma with synchronous non-Hodgkin's lymphoma

We report a case of synchronous gastric adenocarcinoma and abdominal non-Hodgkin's lymphoma in a 56-year-old man. An explo-laparotomy was performed for the purpose of palliative resection of the stomach and to evaluate the nature of splenic and peri-pancreatic mass lesions. The pathologic stage of the gastric carcinoma was stage IB (T2N0M0) and the clinical stage of the diffuse large cell type lymphoma was IIA2S. Following surgery and chemotherapy, the patient is now in a disease-free state.

Menstrual state should be considered in determining sero-positivity of soluble angiogenic factors in breast cancer

We investigated whether blood angiogenic factor (vascular endothelial growth factor, VEGF; angiogenin; basic fibroblast growth factor, bFGF; platelet-derived growth factor-AB, PDGF-AB) levels change during menstrual cycle of healthy premenopausal females or after menopause. We also measured the serum angiogenic factor levels in 34 operable breast cancer patients and compared them to those of healthy volunteer controls. No differences in the four angiogenic factor levels were found between the follicular and luteal phases of normal menstruation. However, angiogenin and bFGF levels were higher in pre-menopausal females than post-menopausal female and young male healthy volunteers. In cancer patients, the sero-positivity rate of the bFGF was 8.8% with menstrual-state-unmatched cut-off points, which increased to 36.4% with menstrual-state-matched cut-off points. This discrepancy was especially high in post-menopausal cancer patients. In conclusion, physiological elevation of the bFGF during normal menstruation can influence the precise interpretation of the pathological elevation of the bFGF in pre-menopausal breast cancer patients.

Telomerase activity and telomere lengths in various cell lines: changes of telomerase activity can be another method for chemosensitivity evaluation

For the cancer cells which have overcome the second mitotic clock (M2), activated telomerase is essential and used as another marker of immortality. Many trials had been initiated to target telomerase, which is known to be specific to tumors. To determine the best in vitro cell system for testing the efficacy of telomerase inhibitors, we evaluated the telomerase activity of various cancer cell lines and measured their telomere lengths. We also treated some cancer cell lines with adriamycin and measured the changes of telomerase activity. Telomerase activity was evaluated in various cell lines with the TRAP (telomeric repeat amplification protocol) assay. Telomerase activity was calculated and translated into arbitrary units by computer-assisted densitometry with the control of telomerase activity in the 293 control cell line. Also, terminal restriction fragment lengths were measured using Southern blotting. We also measured telomerase activity and telomere lengths in 11 benign breast tumor tissues and 19 paired stomach cancer and normal tissues. Cancer cell lines treated with adriamycin we evaluated for changes of telomerase activity and the cell proliferation by MTT assay and dye exclusion test. Telomerase activity of cell lines was 95.3 24.1 unit with a range of 27.6-129.6 unit, while the telomere lengths of those cell lines were variable from 5.0 to 10.4 kbp with a median of 6 kbp. In 11 cancer cell lines which were not yet firmly established, we could not detect any telomerase activity. Low telomerase activity was detected in only 2 benign tumor tissues of breast with a median telomere length of 8.8 (7-10.5) kbp. Among paired 19 gastric cancer and normal tissues, only 7 cancer tissues showed weak telomerase activity. After adriamycin treatment, telomerase activity in YCC-S-1, YCC-S-3, MCF-7 and MCF-7/ADR was decreased in accordance with the changes of the cell numbers. Telomerase is specific to cancer tissues and is expressed differently from organ to organ. Telomerase activity by TRAP assay could be used as a chemosensitivity assay.

Alpha-fetoprotein-producing gastric cancer

We measured the sero-positivity rate of serum alpha-fetoprotein (alphaFP) of gastric cancer patients by ELISA assay; forty-two curatively resected patients, 14 palliatively resected patients, 8 who received explo-laparotomy or bypass surgery and 18 patients with systemic metastasis. The sero-positive rate was 9.8% (8/82) and the positivity increased with cancer progression. Sex, age and pathological type were similar between alphaFP-positive and -negative patients. The overall synchronous hepatic metastasis rates in alphaFP-positive and alphaFP-negative groups were 37.5% (3/8) and 12.2% (9/74), respectively (p=0.08). The predictability of synchronous liver metastasis in eight alphaFP-positive patients were as follows: 37. 5% of total patients (3/8), 50.0% (3/6) of unresectable patients, and 60.0% (3/5) of patients with systemic metastasis. In three alphaFP-positive patient with liver metastasis, all the hepatic lesions were intrahepatic and multiple, while in alphaFP-negative patients, 67% (6/9) of the hepatic lesions was single intrahepatic lesion or surface nodule. The predictability of both synchronous and metachronous liver metastasis in alphaFP-positive gastric cancer patients was 75%. These findings suggested that, in advanced stomach cancer patients, especially in stage IV, alphaFP can be used in predicting liver metastasis during follow-up.

Different expression patterns of MMP-2 and MMP-9 in breast cancer

Among the many biological characteristics of cancer, the matrix metalloproteinase (MMPs) is essential for tumor invasion and metastasis. The relationship between MMP-2 and MMP-9 according to tumor progression has not been studied yet. We evaluated the synchronous expression and activation rate of MMP-2 and MMP-9 in breast cancer tissues and compared them to the clinical parameters in order to determine the clinical significance of MMPs and the possibilities of using them as a therapeutic target. The activity of MMPs was evaluated in 121 breast cancer tissues using zymography and the area of activation was calculated by computer-assisted densitometry in comparison to the activity of a positive control (HT-1080). In 121 tumor tissues, 32 (26.4%) did not express any form of MMPs and 19 (15.7%) showed both expression of MMP-2 and MMP-9. We observed that only one tissue expressed MMP-9 alone, while MMP-2 alone was expressed in 69 tissues. In 88 patients with MMP-2 and/or MMP-9 expression, we were unable to observe any correlation between the activity of MMPs expression or activation rate and the clinical parameters. But MMP-2 and MMP-9 activity increased according to T factor. Rapid production of MMP-9 occurred from T2 (p=0.046), while that of MMP-2 occurred from T3 (p=0.004). In conclusion, MMPs activity was organ specific. The major MMPs in breast cancer was MMP-2 and MMPs activity was different with tumor progression. When MMPs are a specific therapeutic target, we should use different inhibitors according to tumor size, in patients at the same stage.

Physiological and pathological changes of plasma urokinase-type plasminogen activator, plasminogen activator inhibitor-1, and urokinase-type plasminogen activator receptor levels in healthy females and breast cancer patients

The plasma urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1), and urokinase-type plasminogen activator receptor (uPAR) levels were measured in healthy volunteers and breast cancer patients. In pre-menopause healthy females, blood was sampled weekly during one menstruation cycle and menstruation phases (follicular, ovulatory, luteal) were determined by FSH/LH levels. uPA, PAI-1, and uPAR levels were at the nadir during ovulatory phase. uPA level was highest at follicular phase while PAI-1 level was highest at luteal phase. In comparison between pre- and post-menopause states, uPA and uPAR levels were higher in post-menopause state while PAI-1 level was higher in pre-menopause state. In breast cancer patients, uPA, PAI-1, and uPAR positive rates were low when we use the menopause-state-unmatched cut-off points. As we adjusted the cut-off points by menopause states, the PAI-1 positivity increased mainly in post-menopause cancer patients. These findings suggest that there is a minor but possible sequential change of these molecules during menstruation cycle which might blur the pathological positivity in pre-menopause cancer patients. The pathological elevation of PAI-1 was well detected in post-menopause cancer patients, but this elevation did not correlate with tumor burden such as number of metastatic sites or metastatic location. In conclusion, adjustment of physiological changes of uPA, PAI-1, and uPAR is required in determining pathological elevation of the plasma levels in cancer patients, especially in females.

Synchronous elevation of soluble intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) correlates with gastric cancer progression

Soluble forms of ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) have been reported from the supernatant of cytokine-activated endothelial cells, cancer cells and from sera of cancer patients. We measured sICAM-1 and sVCAM-1 from the serum of 20 healthy volunteers and 142 gastric cancer patients by ELISA assay. Ninety-five patients were operable and 47 patients were in-operable at the time of this study. Particularly in the 28 operable patients, we sampled both portal and peripheral blood simultaneously and measured the levels of the soluble forms of cell adhesion molecules (sCAMs). The sCAMs level and sero-positivity rate increased with cancer progression in order of the healthy controls, operable patients, and inoperable patients. In in-operable cancer, the sICAM-1 level increased more with liver metastasis. sICAM-1 and sVCAM-1 did not correlate with each other in either portal or peripheral blood. A total of 58.3% of patients with liver metastasis and 22.9% of patients without liver metastasis showed synchronous expression of both sCAMs (p = 0.03). Synchronous sero-positivity of sCAMs and alpha FP was higher with liver metastasis (p = 0.01). The median overall survival duration which co-expressed both sCAMs was 9 months. This showed a significant difference compared with the sICAMs non-expressing group, where the median survival was not reached until 24 months follow-up (p = 0.002). The synchronous expression of sCAMs was an independent risk factor in gastric cancer patients. We raise the possibility that synchronous sICAM-1 and sVCAM-1 elevation may be a useful monitor to determine tumor burden in gastric cancer.

A comparative study of intravenous granisetron versus intravenous and oral ondansetron in the prevention of nausea and vomiting associated with moderately emetogenic chemotherapy

We conducted a prospective, randomized, open, single-center, parallel group study comparing the anti-emetic efficacy and toxicity of granisetron with that of ondansetron in patients receiving moderately emetogenic chemotherapy. From December 1994 to May 1995, patients who were to receive moderately emetogenic chemotherapy for the first time or who had not received chemotherapy (80 to 100 mg/m2 of cisplatin or 40 mg/m2 of doxorubicin) within 4 weeks previously were enrolled in this study. The following anti-emetic regimens were used: 3 mg of granisetron were given intravenously before chemotherapy for a single dose; 8 mg of ondansetron were given intravenously before chemotherapy and then every 8 hours for a total of 3 doses, plus 8 mg of an oral maintenance dose every 12 hours for 5 consecutive days. We evaluated 97 patients (48 received granisetron and 49 received ondansetron). In the first 24 hours after chemotherapy, complete and major responses were achieved in 76.6% of the patients receiving granisetron and in 72.9% of patients receiving ondansetron (p = 0.9033). Additionally, there was no difference in the control of delayed nausea and vomiting between the two groups (51.1% versus 54.2%, p = 0.9200), and there were no significant adverse effects or toxicities. We have concluded that a single dose of granisetron is as effective in prophylaxis of emesis induced by moderately emetogenic chemotherapy as a triple dose of ondansetron plus oral maintenance.

Retrospective comparison of infusional 5-fluorouracil, doxorubicin, and mitomycin-C (modified FAM) combination chemotherapy versus palliative therapy in treatment of advanced gastric cancer

About one-third of patients with gastric cancer are unresectable at the time of diagnosis. Their median survival is < 6 months, with a grave prognosis. The purpose of this study was to assess the efficacy of a modified FAM (mFAM) regimen in advanced gastric cancer. We retrospectively reviewed the clinical records of 409 advanced gastric cancer patients who had not received curative surgery. Among 409 patients, 202 patients were treated with an mFAM regimen (infusional 5-FU + doxorubocin + mitomycin-C), and 207 patients received no chemotherapy (control group). No differences were found in clinical parameters between the two groups. The 1-year survival rates were 34.1% for the mFAM-treated group and 22.5% for the control group (p = 0.0135). In subset analysis, a higher 1-year survival rate was demonstrated in patients with mFAM and palliative surgery. Of the 154 evaluable patients in the mFAM-treated group, the response rate was 17.5%. In these patients, median response duration was 30 weeks, and progression-free survival was 23 weeks. Overall toxicity of mFAM regimen was relatively tolerable and reversible. In conclusion, FAM combination chemotherapy, which has been used as a standard therapy, prolonged survival after modification of the administration schedule and combination with palliative surgery. A prospective randomized study is warranted to confirm this conclusion from our retrospective study.

Comparison of biological phenotypes according to midkine expression in gastric cancer cells and their autocrine activities could be modulated by pentosan polysulfate

We studied biological phenotypes of gastric cancer cell lines based on a novel heparin-binding growth/differentiation factor (midkine (MK)) expression. MK expression was found in 67% (6/9) of the gastric cancer cell lines and 56% (14/25) of the primary cancer tissues. Gastric cancer cell lines with MK expression showed higher colony forming activity in soft agar assay and endothelial cell growth stimulatory effect in cross-feeding assay than cells which did not express MK. However, urokinase-type plasminogen activator (uPA) expression and tumor invasiveness did not correlate with MK expression. Growth of MK expressing cells was inhibited by a heparin-binding blocking agent, pentosan polysulfate (PPS). In cancer tissues, MK expression correlated with tumor size, suggesting in vivo autocrine and paracrine activity. This proliferation promoting activity of MK can be targeted by an anti-heparin binding agent as a biotherapy model in gastric cancer.

Sequential production and activation of matrix-metalloproteinase-9 (MMP-9) with breast cancer progression

The degradation of the basement membrane by matrix-metalloproteinase (MMP) and serine protease is a critical point in tumor invasion and metastasis. We measured the activity of MMP-9 from 28 normal, 12 benign and 126 breast cancer tissues using gelatin zymography with an image analysis system. ProMMP-9 was expressed in 17.5% of the cancer patients compared to 2.5% in 40 non-cancerous tissues (p = 0.014). The mature form of MMP-9 (82 kD) was expressed only in T2-T4 stages. During the early phase of breast cancer (DCIS and T1 stage) progression, only production of proMMP-9 increased. However, as the cancer grew or invaded skin (T2-T4), or with lymphovascular permeation, both production and activation of MMP-9 increased. In conclusion, proMMP-9 production was the main cause of increased MMP-9 activity during the early phase, while both production and activation increased in the late phase of breast cancer.

High level of urokinase-type plasminogen activator is a new prognostic marker in patients with gastric carcinoma

BACKGROUND

Prognosis of gastric carcinoma is related to invasion and metastasis. Evidence has accumulated that invasion and metastasis in solid tumors require the action of tumor-associated proteases, which promote the dissolution of the surrounding tumor matrix and the basement membrane. The serine protease urokinase-type plasminogen activator (uPA) and its inhibitor, plasminogen activator inhibitor-1 (PAI-1), appear to have a major function in these processes. Recent reports have demonstrated that expression of these proteolytic enzymes is elevated in breast and colon carcinoma and that it can be associated with invasiveness and poor prognosis. Therefore, the authors evaluated whether the expression and activation of uPA and PAI-1 might be of clinical value as a tumor/biologically defined risk factor in patients with gastric carcinoma.

METHODS

Enzyme-linked immunoadsorbent assays were used to test for uPA antigens and PAI-1 in tissue extracts of normal and cancerous tissue from 160 gastric carcinoma patients who were enrolled in the Yonsei Cancer Center Study Group.

RESULTS

Both uPA and PAI-1 levels were significantly higher in cancerous tissues than in normal tissues (uPA: 9.4 +/- 8.7 vs. 5.3 +/- 3.1 ng/mg protein cytosol; PAI-1: 10.9 +/- 9.1 vs. 5.8 +/- 2.9 ng/mg protein cytosol), (P < 0.001, respectively). Both high uPA and PAI-1 levels were associated with differentiation of the tumor (P = 0.04 and P = 0.004, respectively), and a high PAI-1 level was associated with lymph node metastasis at an advanced stage (P = 0.003 and P = 0.04, respectively). There was a correlation between the levels of uPA and PAI-1 expression in cancerous tissues (correlation coefficient = 0.57). In univariate analysis, a high level of uPA or PAI-1 was associated with a short relapse free survival, but in multivariate analysis only a high level of uPA was an independent prognostic parameter for a short relapse free survival for gastric carcinoma patients.

CONCLUSIONS

These data indicate that uPA is a new independent variable for the identification of high risk gastric carcinoma patients. Therefore, therapy targeting uPA can be applied as a new biologic treatment modality for these individuals.

Relationship between p53 overexpression and gastric cancer progression

The relationship between p53 overexpression and clinicopathologic variables in gastric cancer was evaluated using 304 paraffin-embedded gastric tumor tissues. DO7, a murine monoclonal antiserum to p53 protein, was used for the immunohistochemical analysis. Positive staining was found in 129 tumors (42.2% of all tumors). Overexpression of p53 was not associated with sex, location of the tumor in the stomach or the type of Borrman's tumor. The overexpression rate of p53 protein was 30.4% (28/92) in stage II and 47.6% (101/212) in stage III (p = 0.007). While there was no significant association between p53 protein accumulation and T stage, there was a significant association with N stage, i.e. p53 overexpression was 27.4% (17/62) in the node-negative group and 46.3% (112/242) in the node-positive group (p = 0.011). In 79 patients, in whom corresponding primary gastric tumor and regional lymph node metastases were available, overexpression was found in 34 (43%) primary tumors and in 38 (48.1%) node samples, with a concordance rate of 67.1% in terms of p53 expression. Mean numbers of regional lymph node involvement by the tumor were 6.1 in the group with p53 overexpression and 5.2 in the group showing no immunoreactivity (p = 0.051). These findings suggest that p53 overexpression is related to gastric cancer progression and that immunoreactivity in the metastatic lymph nodes show the dependency on p53 expression in the primary tumor.