PURPOSE: We determined the clinical significance of telomerase activity and telomere length in breast cancer patients and also developed the measuring system of telomerase activity change with RNAse A pre-treatment. MATERIALS AND METHODS: We measured the telomerase activity in 71 breast cancer tissues and paired normal tissues with TRAP (Telomeric Repeat Amplification Protocol) assay. Telomerase activity was calculated by computer-assisted densitometry compared to telomerase activity of the 293 control cell line. To develop the measuring system of telomerase activity modulation, we measured the telomerase activity after the treatment with RNAse A, 150microgram/ml, which inhibited 70% of telomerase activity compared to control in the 293 control cell line. In 59 paired tissues with telomerase activity, terminal restriction fragment (TRFs) length were measured using Southern blotting. RESULTS: Sixty-three out of 71 cancer tissues showed telomerase activity (88.7%), while no telomerase activity was detected in their paired normal tissues. Telomerase activity was correlated to the node metastasis (p=0.02) and stage (p=0.005), but not to the tumor size or the hormonal receptor status. TRFs were neither specific to tumor tissues nor related to any of the clinical parameters. However, changes of TRFs of the tumor tissues from their paired normal tissues were correlated to the telomerase activities. Also the patients with different TRFs between cancer and normal tissues were in more advanced stage. After pre-treatment with the 150microgram/ml of RNAse A, telomerase activity in the tumor tissues showed variable inhibition. Relative inhibition, the ratio of inhibited telomerase activity in each tumor tissue compared to the inhibition of 293 control cell line, was proportional to the telomerase activity. CONCLUSION: In breast cancer, telomerase activity was specific to the tumor tissues and correlated to tumor progression. A combination of telomerase activity and TRFs changes can be used as a guidline in detecting a better candidate for telomerase inhibition. Semi-quantitative assay with RI system can be used in evaluating the changes of telomerase activity after treatment with a new telomerase inhibitor with TRAP assay.
Biological Therapy* ; Blotting, Southern ; Breast Neoplasms* ; Breast* ; Cell Line ; Densitometry ; Humans ; Neoplasm Metastasis ; Ribonuclease, Pancreatic ; Telomerase* ; Telomere

Twelve male patients with operable breast cancer were evaluated for the expression of prognostic factors by immunohistochemical staining assay. Seven patients were stage I and II, and five patients were stage III. Axillary lymph node positivity was 42%. Nine patients were nuclear grade I, three were nuclear grade II, and none were nuclear grade III. The expression rate of EGFR (epidermal growth factor receptor), ER (estrogen receptor) were 8.3%, 70.0% respectively. This limited data suggest better tumor behavior in male than in female breast cancer. Adjuvant treatment should be considered in male breast cancer just as in females, based on axillary lymph node and ER states.
Breast Neoplasms/*chemistry/pathology ; Carcinoma/*chemistry/pathology ; Human ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Neoplasm Staging ; Prognosis ; Receptor, Epidermal Growth Factor/*analysis ; Receptors, Estrogen/*analysis

We have studied the patterns of P-glycoprotein expression before and after 3 cycles of induction chemotherapy (5-fluorouracil, adriamycin and cyclophosphamide) using immunohistochemically stained paraffin-embedded specimen of 28 patients with locally advanced breast cancer. The frequency of P-glycoprotein expression in untreated breast cancer turned out to be very low: only one out of 28 untreated, biopsy specimen at the time of diagnosis was positive. The frequency of P-glycoprotein expression was markedly increased from 9.1% before chemotherapy to 63.6% after induction chemotherapy (p = 0.006). After 3 cycles of induction chemotherapy, 25 patients had obtained clinical response to chemotherapy (4, CR; 21, PR). Eleven out of 25 tumors (44%) showing clinical response and all three tumors (100%) with minimal response have expressed P-glycoprotein. One out of 6 patients (16.7%) with microscopic residual tumor seen in mastectomy specimen expressed P-glycoprotein, whereas 13 of 22 patients (59.1%) with gross residual tumor showed the presence of P-glycoprotein (p = 0.08). The frequency of intrinsic P-glycoprotein expression in untreated breast cancer was quite low, but approximately half of the patients do acquire P-glycoprotein expression during the cycles of induction chemotherapy. Therefore, the results suggest that the immunohistochemical detection of P-glycoprotein on residual tumor cells after induction chemotherapy can predict acquired drug resistance in breast cancer.
Adult ; Aged ; Breast Neoplasms/chemistry/*drug therapy/pathology ; Breast Neoplasms/chemistry/*drug therapy/pathology ; Drug Resistance ; Drug Resistance ; Female ; Human ; Immunohistochemistry ; Membrane Glycoproteins/*analysis ; Middle Age ; P-Glycoprotein

PURPOSE: For tumor growth, invasion and metastasis, a cascade of linked sequential biological events is essential; overproduction of growth factors, activation of proteolytic enzymes, induction of tumor angiogenesis, and enhanced tumor cell motility and attachment. We tried to test whether the biological therapy against the biological targets can modulate the specific biological characteristics, and furthermore increased anti-tumor effects can be induced when the biological therapy and cytotoxic chemotherapy were combined. MATERIALS AND METHODS: YCC-1, 2, 3, 7, and AGS human gastric cancer cell lines were used in these studies. Pentosan polysulfate (PPS) as a heparin-binding growth factor (HBGF) inhibitor, Tranexamic acid as a plasmin inhibitor, Adriamycin as a chemotherapeutic agent, were selected. The methods were Northern blot analysis for the detection of Midkine (MK) expression, soft agar assay for autocrine tumorigenicity. The expression of uPA, PAI-1 was determined by ELISA, while the MMPs activities were evaluated by zymography. The effects of each drug on tumorigenicity and tumor cell proliferation were evaluated by soft agar assay and cell proliferation assay, respectively. RESULTS: YCC-3, 7, AGS cell lines expressed MK mRNA, whereas YCC-1, 2 did not. YCC-2 cell line showed increased expression of uPA and MMP activities. Only MK expressing YCC-3 and 7 cell lines showed the tumorigenicity. PPS suppressed the colony forming activities as much as Adriamycin did (PPS; 8~24%, Adriamycin; 12~40%), but it showed only cytostatic effects in cell proliferation assay (PPS; 60~103%, Adriamycin; 22~97%). When PPS was combined with Adriamycin on the Adriamycin resistant, MK expressing YCC-7 cell line, the growth inhibition rate increased up to 84%, while that of PPS or Adriamycin single treatment was 40%, 22%, respectively (p=0.001). CONCLUSION: The modulation of specific biological targets can induce the anti-tumor effects. This suggests the possible clinical application of biological therapy in gastric cancer.
Agar ; Antifibrinolytic Agents ; Biological Therapy ; Blotting, Northern ; Cell Line* ; Cell Movement ; Cell Proliferation ; Doxorubicin ; Drug Therapy ; Enzyme-Linked Immunosorbent Assay ; Humans* ; Intercellular Signaling Peptides and Proteins ; Matrix Metalloproteinases ; Neoplasm Metastasis ; Pentosan Sulfuric Polyester ; Peptide Hydrolases ; Plasminogen Activator Inhibitor 1 ; Population Characteristics ; RNA, Messenger ; Robenidine ; Stomach Neoplasms* ; Tranexamic Acid

The expression of p-glycoprotein (p-gp) was evaluated in pre- and post-chemotherapy states after the administration of adriamycin-based chemotherapy in 24 gastric cancer patients. Among them, group A was composed of twelve patients who relapsed after surgery plus adjuvant chemotherapy and group B was composed of another twelve patients who received neoadjuvant chemotherapy plus surgery. Pre-chemotherapy p-gp was evaluated in 18 out of 24 patients (6 patients had no pre-chemotherapy paraffin blocks) and post-chemotherapy p-gp was evaluated from all 24 patients. Pre- and post-chemotherapy p-gp was expressed in 5 of 18 patients (27.8%), and 9 of 24 patients (37.5%), respectively, with immunohistochemical stain using monoclonal antibody JSB-1. No differences of disease-free survivals were observed in Group A based on post-chemotherapy p-gp expression from relapsed lesions. In Group B, there was a higher relapse rate (p = 0.04) and a lower one-year disease-free survival rate (p = 0.04) in post-chemotherapy p-gp positive patients when adjuvant treatment was done with the same regimen as neoadjuvant chemotherapy. In all patients studied, post-chemotherapy p-gp expression correlated with a higher systemic recurrence (p = 0.04). These data suggest that p-gp can be induced by an adriamycin-based chemotherapy in gastric cancer. Thus, we suggest that the prognosis of gastric cancer may be poor if a multidrug resistance (MDR)-related regimen is used in the presence of p-gp after neoadjuvant chemotherapy with an adriamycin-based regimen, even if the initial response is good.
Adult ; Aged ; Combined Modality Therapy ; Dose-Response Relationship, Drug ; Doxorubicin/administration & dosage/*therapeutic use ; Drug Resistance ; Female ; Human ; Immunohistochemistry ; Male ; Middle Age ; Neoplasm Recurrence, Local ; P-Glycoprotein/*metabolism ; Stomach Neoplasms/*drug therapy/*metabolism/surgery ; Survival Analysis

No abstract available.
Cyclosporine* ; Drug Resistance, Multiple* ; Humans* ; Lung Neoplasms* ; Lung* ; Tamoxifen* ; Verapamil*

The intensive use of chemotherapeutic agents for the treatment of cancer has resulted in the cure or improved survival of many patients. But unfortunately, many cancers including human hepatocellular carcinoma (HCC) don't respond to chemotherapy. One of the major mechanisms for the drug resistance in the HCC is an elevated MDR1 RNA expression which makes cells become multidrug resistant. To overcome the multidrug resistance (MDR) phenotype, a high dose of verapamil is required both clinically and experimentally. Accordingly we have examined the MDR modulating effects with combinations of tamoxifen, cyclosporin A, and verapamil in vitro with the physiologically achievable concentrations of each agent, i.e., 2.0 microM/L for tamoxifen, 1.6 microM/L for cyclosporin A, and 2.5 microM/L for verapamil respectively in HCC lines. As expected, verapamil alone with the physiologically achievable concentration at which we tested didn't enhance the doxorubicin cytotoxicity in the HCC lines. Furthermore, any verapamil combination with cyclosporin A or tamoxifen was not effective in overcoming the doxorubicin resistance in the high MDR1 expressor (Hep-G2) line. However tamoxifen reduced the IC50 of doxorubicin by a factor of 1.9 in the low MDR1 expressor (SK-Hep1) and 1.1 in the high MDR1 expressor line (p< 10(-5) respectively). Of interest, combinations of tamoxifen and cyclosporin A showed a significant reduction in the IC50 of doxorubicin in both HCC lines. The IC50 of doxorubicin was reduced by a factor of 3.9 and 1.3, i.e., from 0.023943 micrograms/ml to 0.006157 micrograms/ml (p< 10(-5)) in the SK-Hep1 cell line, and 0.068819 micrograms/ml to 0.052442 micrograms/ml (p< 10(-5)) in Hep-G2 respectively when tamoxifen and cyclosporin A were administered together. Both the estrogen and progesterone receptors in the SK-Hep1 and Hep-G2 lines were less than 0.01 fmol/mg of cytosol protein, respectively. It is therefore suggested that the reversal of doxorubicin resistance is unrelated to their anti-estrogenic activity in the HCC lines. Three modulator combinations of tamoxifen, cyclosporin A, and verapamil were not more effective than the combination of tamoxifen and cyclosporin A on the sensitivity to doxorubicin. MDR modulators of tamoxifen, cyclosporin A, and verapamil didn't reduce the IC50 of cisplatin to the clinically achievable concentration range in HCC lines. In summary, the combination of tamoxifen and cyclosporin A at the concentrations normally seen after clinical administration of these modulators showed significant synergism on the sensitivity to doxorubicin in both low and high MDR1 expressor HCC lines. These data indicate the need for in vivo trials.
Antineoplastic Agents/*pharmacology ; Carcinoma, Hepatocellular/*physiopathology ; Cyclosporine/*pharmacology ; Drug Resistance ; Human ; Liver Neoplasms/*physiopathology ; Support, Non-U.S. Gov't ; Tamoxifen/*pharmacology ; Tumor Cells, Cultured/drug effects ; Verapamil/*pharmacology

No abstract available.
Carcinoma, Non-Small-Cell Lung* ; Cisplatin* ; Drug Therapy, Combination* ; Etoposide* ; Radiotherapy*

No abstract available.
P-Glycoprotein* ; Stomach Neoplasms*

PURPOSE: Leptomeningeal carcinomatosis occurs in about 5% of patients with solid tumor and is being diagnosed with increasing frequency as patients live longer and as neuro-imaging studies improve. In general, the most commom cancers that involved the leptomeninges are breast cancer, lung cancer, and malignant melanoma. MATERIALS AND METHODS: We investigated 25 patients presented with multiple neurologic symptoms and signs who were diagnosed with leptomeningeal carcinomatosis at the Yonsei Cancer Center from January 1990 to December 1999. RESULTS: The primary disease of leptomeningeal carcinomatosis were stomach cancer (10 cases), breast cancer (7 cases), lung cancer (5 cases), unknown primary cancer (2 cases) and common bile duct cancer (1 case). All patients were presented with multiple neurologic symptoms and signs involving the central nervous system (CNS), cranial nerve or spinal nerves. Twenty-one of twenty- five patients were treated with intrathecal chemotherapy, radiotherapy, or combination therapy. Fourteen of them (66.7%) experienced improvement or stabilization of neurologic symptom and sign. The median survival was 122 days (10-2190). CONCLUSION: In conclusion, although early diagnosis and active treatment of leptomeningeal carcinomatosis may improve the quality of life in selected patients, the median survival was relatively short. Therefore, new diagnostic and therapeutic strategy for leptomeningeal carcinomatosis were needed.
Breast Neoplasms ; Central Nervous System ; Common Bile Duct ; Cranial Nerves ; Drug Therapy ; Early Diagnosis ; Humans ; Lung Neoplasms ; Melanoma ; Meningeal Carcinomatosis* ; Neurologic Manifestations ; Quality of Life ; Radiotherapy ; Spinal Nerves ; Stomach Neoplasms