Molecular subtypes of breast cancer emerging in young women in Taiwan: evidence for more than just westernization as a reason for the disease in Asia.

BACKGROUND: In the past two decades, the incidence of breast cancer in young Taiwanese females has been rapidly increasing, approaching the risk level of western countries. As a first step to investigate the possible etiology, we examined the molecular subtypes of female breast cancer in Taiwan. METHODS: This study included 1,028 consecutive patients with breast cancer diagnosed in National Taiwan University Hospital between 2004 and 2006. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2, cytokeratin 5/6, and epidermal growth factor receptor expression and/or gene amplification were analyzed. RESULTS: Younger (50 years) patients. The higher prevalence of luminal A subtype was mainly attributed to a higher ER (75% versus 63%; P < 0.001) and PR (47% versus 33%; P < 0.001) expression rate in younger patients than older patients. Tumors with histologic grade 3 were less prevalent in younger patients than in older patients (23% versus 30%; P = 0.01). For very young (<35 years) patients, the molecular subtype distribution, ER and/or PR expression rate, and histologic grade were not significantly different from those of less young (35-50 years) patients. CONCLUSIONS: Young breast cancer patients in Taiwan are characterized by a high prevalence of luminal A subtype and low prevalence of histologic grade 3 tumor and/or basal-like subtype. These features are distinct from young breast cancer patients in western countries.

Prognostic significance of beta-catenin and topoisomerase IIalpha in de novo acute myeloid leukemia.

The Wnt/beta-catenin signaling is important for controlling self-renewal of hematopoietic stem cells and its constitutive activation has recently been documented in a significant proportion of acute myeloid leukemia (AML) cases. Topoisomerase IIalpha (Topo IIalpha) is a marker of cell proliferation and a crucial target for anthracycline cytotoxicity, the mainstay of management employed in AML. We retrospectively investigated the prognostic roles of beta-catenin and topo IIalpha in a cohort of 59 patients with newly diagnosed AML by immunohistochemistry. Aberrant beta-catenin expression was demonstrated in 13 patients (22%), and it was more likely to occur in those with unfavorable karyotypes. Advanced age and poor performance status adversely influenced the achievement of complete remission, while neither aberrant beta-catenin expression nor enhanced topo IIalpha activity did. On multivariate survival analysis, four factors independently predicted a shortened overall survival: aberrant beta-catenin expression, high topo IIalpha activity, poor-risk cytogenetics, and presence of at least one comorbidity factor. Our results suggest that both beta-catenin and topo IIalpha independently predicted an adverse prognosis and might serve as new markers for risk stratification in AML patients.

Phase II randomized study of daily gefitinib treatment alone or with vinorelbine every 2 weeks in patients with adenocarcinoma of the lung who failed at least 2 regimens of chemotherapy.

BACKGROUND: The objective of this study was to assess the efficacy of adding chronic, intermittent, low-dose vinorelbine to gefitinib treatment for patients who had adenocarcinoma of the lung who failed>or=2 regimens of chemotherapy. METHODS: Patients were randomized into 2 arms: Oral gefitinib 250 mg daily (the G arm) or vinorelbine 15 mg/m2 as an intravenous infusion on Day 1 and oral gefitinib 250 mg daily on Days 2 through 14 every 2 weeks (the GV arm). From August 2004 to October 2005, 48 patients were enrolled. Epidermal growth factor receptor (EGFR) exon 18 through 21 nucleotide sequence analysis and fluorescence in situ hybridization were performed in patients who had tumor tissue specimens available for analysis. RESULTS: After randomization, each arm had 24 patients. However, 3 patients refused vinorelbine treatment and were given gefitinib treatment only. Thus, 27 patients received G treatment, and 21 patients received GV treatment. Objective response rates were 55.6% in the G arm and 52.4% in the GV arm. All toxicities in both arms were mild. The 1-year progression-free survival rate was 57.1% in the GV arm and 21.2% in the G arm (P=.008). The median survival was 13.3 months in the G arm and 23.4 months in the GV arm (P=.1231). Three of 6 patients (50%) had an exon 19 in-frame deletion, and 2 of 10 patients had EGFR gene high polysomy or amplification (20%). CONCLUSIONS: Gefitinib was highly effective in ethnic Chinese patients with adenocarcinoma of the lung who failed previous platinum and taxane treatment. The addition of low-dose vinorelbine every 2 weeks produced a significantly better 1-year progression-free survival rate.

Effect of age on pulmonary metastases and immunotherapy in young and middle-aged mice.

BACKGROUND: We used B16-F10 (B16) melanoma tumor cells and syngeneic C57BL/6 (B6) mice as a study model for pulmonary metastases, to better understand whether or not there exist differences in tumorigenicity and in the effectiveness of immunotherapy as a function of host age (1-, 3-, 12- and 24-month-old). METHODS: Intravenous injection of B16 melanoma cells were administered to B6 mice of different ages with/without interleukin (IL)-2 and IL-12 daily treatment. Tumor growth, splenocyte function, serum cytokines (IL-10, interferon-gamma, vascular endothelial growth factor) and survival were compared. RESULTS: The study showed that, without IL-2 and IL-12 treatment, middle-aged mice suffering from pulmonary metastases had fewer pulmonary metastases and better survival than younger mice suffering from pulmonary metastases. Three days' IL-2 plus IL-12 treatment could not prolong mice survival, but prolonged treatment significantly improved the survival of both the younger and older tumor-bearing mice, especially the older mice, despite the fact that the younger mice had a better serum cytokine and splenocyte cellular immune response to cytokine treatment. CONCLUSION: The young B6 mice that suffered from B16 pulmonary metastases had a poorer prognosis than the middle-aged mice. Short-term IL-2 plus IL-12 treatment is ineffective in prolonging survival, and a longer duration of treatment is needed. This kind of immunotherapy was effective in both the young and middle-aged mice, but it was more effective in the middle-aged mice.

Effects of paclitaxel and doxorubicin in histocultures of hepatocelular carcinomas.

Cancer has been the leading cause of death in Taiwan over the past two decades and liver cancer is the leading cause of all cancer deaths in Taiwan with a trend of increase in incidence. Therapeutic options and efficacy for liver cancer have been limited and the 5-year survival rate is less than 7% in the Unite States. The study was conducted to establish a histoculture system of human hepatocellular carcinomas (HCC) for biological and pharmacological studies and to determine the efficacy of anticancer drugs with the established HCC histocultures. Patient HCC tissues freshly obtained after surgeries were prepared and histocultured. The histocultured HCC were treated with doxorubicin and paclitaxel of various concentrations for 96-h. Upon drug treatments, the activity of tumor cell proliferation and extent of cell death induction were measured and changes of the alpha-fetoprotein levels in the culture medium were determined. We demonstrated that human HCC can be successfully cultured in a 3-dimensional histoculture system and used for pharmacological studies. Doxorubicin and paclitaxel showed concentration-dependent activities in anti-proliferation and cell death induction against the human HCC. Inhibitory effects of both drugs on alpha-fetoprotein production of the cultured HCC were in agreement with their anti-proliferative effects. Exposure time-dependent antitumoral effects of paclitaxel treatments at 3-, 24-, and 96-h against the histocultured HCC PLC/PRF/5 xenograft tumors were also observed. In conclusion, we have demonstrated a histoculture system for patient HCC and it can be utilized in selection of active drugs prior to treatments in patients and in evaluation of new agents against HCC, for which therapeutic agents are in desperate needs worldwide.

The sensitivity of human mesenchymal stem cells to ionizing radiation.

PURPOSE: Recent studies have shown that mesenchymal stem cells (MSCs) obtained from bone marrow transplantation patients originate from the host. This clinical observation suggests that MSCs in their niches could be resistant to irradiation. However, the biologic responses of bone marrow MSCs to irradiation have rarely been described in the literature. METHODS AND MATERIALS: In this study, human bone marrow-derived, clonally expanded MSCs were used to investigate their sensitivity to irradiation in vitro, and the cellular mechanisms that may facilitate resistance to irradiation. The human lung cancer cell line A549 and the breast cancer cell line HCC1937 were used as controls for radiosensitivity; the former line has been shown to be radioresistant and the latter radiosensitive. We then examined their in vitro biologic changes and sensitivities to radiation therapy. RESULTS: Our results suggest that MSCs are characterized as resistant to irradiation. Several cellular mechanisms were demonstrated that may facilitate resistance to irradiation: ATM protein phosphorylation, activation of cell-cycle checkpoints, double-strand break repair by homologous recombination and nonhomologous end joining (NHEJ), and the antioxidant capacity for scavenging reactive oxygen species. CONCLUSIONS: As demonstrated, MSCs possess a better antioxidant reactive oxygen species-scavenging capacity and active double-strand break repair to facilitate their radioresistance. These findings provide a better understanding of radiation-induced biologic responses in MSCs and may lead to the development of better strategies for stem cell treatment and cancer therapy.

Comprehensive breast cancer adjuvant digital summary.

BACKGROUND: Patients with breast cancer often fail to recall the details of their original diagnosis and adjuvant therapy with the passage of time. Subsequent follow-up and treatment at a later time and a different institution wastes valuable time and effort to retrieve the original data. PATIENTS AND METHODS: Twenty-five consecutive patients with breast cancer of all stages admitted for adjuvant/neoadjuvant treatment and surgical excision were entered on study. An individualized comprehensive visual evaluation summary sheet (VESS) was created that detailed initial diagnosis, preceding relevant investigations, drug scheduling, and dosages of adjuvant therapy. Completion of a VESS required a computer, a digital camera with connection to a microscope, and radiology images over the PACS system. The completed one-page summary can be printed or stored. RESULTS: A VESS takes up an average of 4.4 MB (1.24-8 MB), each containing 11.5 images (range, 4-23 images), spanning a time period of around 216 days (range, 125-558 days). CONCLUSIONS: Patients received a complete summary of pertinent information concerning their diagnosis and adjuvant therapy.

Tumor beta-1,4-galactosyltransferase IV overexpression is closely associated with colorectal cancer metastasis and poor prognosis.

PURPOSE: To elucidate the significance of beta-1,4-galactosyltransferase IV (beta-1,4-GT-IV) in the clinical presentation and prognostication of colorectal cancer. EXPERIMENTAL DESIGN: Tissue lysates from paired tumor and nontumor tissues of a colon cancer patient were labeled separately with fluorescent dyes Cy5 and Cy3 for two-dimensional difference in-gel electrophoresis. Subsequent matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and immunoblot analyses identified a down-regulated level of beta-1,4-GT-IV in the tumor tissue. In the follow-up study, paired tissue lysates were obtained from 100 colorectal cancer patients with immunoblot analyses done to compare the levels of beta-1,4-GT-IV expression in these patients. RESULTS: Of 100 colorectal patients studied, 48% had down-regulated expression of beta-1,4-GT-IV in the tumor tissue but 28% of patients exhibited elevated beta-1,4-GT-IV levels. Increased beta-1,4-GT-IV in the tumor tissue was significantly coexistent with raised serum level of CA-199 and the presence of tumor metastasis (P=0.006 and P<0.001, respectively) but was independent of age and gender of patient, tumor site, tumor size, serum level of carcinoembryonic antigen, grade of tumor cell differentiation, and depth of tumor invasion. The results of logistic regression analyses suggested that tumor beta-1,4-GT-IV overexpression and tumor invasion, but not other patient variables such as tumor size and serum levels of carcinoembryonic antigen and CA19-9, were significantly correlated with the occurrence of metastases (P<0.05). In a multivariate regression analysis, the patient group with tumor beta-1,4-GT-IV overexpression strongly predicted for tumor metastasis (odds ratio, 10.009; 95% confidence interval, 2.992-33.484; P<0.001). Likewise, tumor beta-1,4-GT-IV overexpression was significantly associated with poor overall survival (P<0.01). By Cox regression analysis, this association remained significant even after adjustment for tumor metastasis (P=0.048). CONCLUSION: Increased beta-1,4-GT-IV expression in tumor tissue was strongly associated with tumor metastases and poor prognosis in colorectal cancer.

Novel rapid tissue lysis method to evaluate cancer proteins: correlation between elevated Bcl-X(L) expression and colorectal cancer cell proliferation.

AIM: We optimized a rapid and efficient tissue lysis method using the MagNA Lyser (Roche, Germany). Using this novel method combined with immunoblot analysis, we investigated the correlation between abnormal Bcl-X(L) expression and clinicopathological characteristics in colorectal cancer. METHODS: Tissue samples from Sprague-Dawley rats were tested to determine optimal lysis conditions for use with MagNA Lyser. We next used the new method to extract tissue proteins from the tumor tissue of a colorectal cancer patient. The availability of extractable tissue proteins for proteomic study was demonstrated by two-dimensional (2D) gel electrophoresis and subsequent matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. In addition, we prepared tissue lysates from paired tumor tissues and adjacent nontumor tissues of 50 colorectal carcinoma patients. Ensuing immunoblot analyses were performed to detect the level of Bcl-X(L) expression. RESULTS: The optimal sample sizes processed were found to be around 200 mg, with oscillation frequency of 6500 r/min for 80 s. Test of the first human tissue lysate confirmed that the MagNA Lyser method was adequate for protein extraction and subsequent identification by current proteomic protocols. The method was also applicable to immunoblot analysis. Thirty of 50 (60%) colorectal patients exhibited higher level of Bcl-X(L) expression in their tumor tissues. Raised level of Bcl-X(L) expression correlated with patients' gender and tumor cell proliferation index (P = 0.037 and P<0.001, respectively), but was independent of clinicopathological characteristics and overall survival. CONCLUSION: We report a novel tissue lysis method applicable to proteomic and immunoblot analyses, which can facilitate the discovery and detection of cancer protein alterations.

erb-b2 amplification by fluorescence in situ hybridization in breast cancer specimens read as 2+ in immunohistochemical analysis.

We conducted this study to ascertain the prevalence of erb-b2 gene amplification in breast cancer specimens read as 2+ in immunohistochemical analysis. Slides from patients with metastatic or recurrent breast cancer were eligible for fluorescent in situ hybridization (FISH) study if they were read as 2+ immunohistochemically for erb-b2 by a certified pathologist. The PathVysion kit (Vysis, Downers Grove, IL) was used for FISH studies. Amplification of the erb-b2 gene was defined as an erb-b2/CEP17 (chromosome 17 centromere) ratio of 2 or more in 30 tumor cells counted. From May 2003 to June 2004, 221 slides were submitted from 24 hospitals around the island. Of 216 successful hybridizations, 96 (44.4%) were determined to be erb-b2 amplified. In addition, the topoisomerase IIa gene was coamplified in 11 (21%) of 53 and deleted in 8 (15%) of 53 erb-b2 amplified cases. The erb-b2 gene amplification rate was very high in cases determined to be 2+ by immunohistochemical analysis; therefore, determination of erb-b2 status by FISH in cases scored 2+ immunohistochemically is strongly recommended.

Impact of circulating free tumor cells in the peripheral blood of colorectal cancer patients during laparoscopic surgery.

Despite widespread use of laparoscopic surgery for colorectal operations, its application for curative resection of colorectal cancer is still controversial. One of the major concerns is the impact of the laparoscopic procedure on dissemination of tumor cells. The main purpose of this study was to investigate the impact of laparoscopic surgery on circulating tumor cells in colorectal cancer patients. Quantitation of circulating free tumor cells (FTCs) was performed preoperatively, during the operation, and 14 days later by means of real-time quantitative reverse transcriptasepolymerase chain reaction (RT-PCR) targeting guanylyl cyclase C (GCC) mRNA in 42 colorectal cancer patients undergoing laparoscopic resections. Despite an increasing trend of FTC detection in patients with advancing stage, there is no significant difference in the preoperative FTC level by disease stage. No elevation in FTC level was found during the laparoscopic procedure in most patients compared with their preoperative FTC value. Patients with a persistently high FTC load [per nucleated blood cells (NBCs)] (> 10(2) FTCs/10(6) NBCs) 2 weeks postoperatively portends a poor prognosis regarding disease recurrence and tumor-related mortality when compared to those with an undetectable or low FTC load (< or = 10(2) FTCs/10(6) NBCs). We concluded that the laparoscopic procedure itself had no significantly deleterious effect on circulating FTCs and that the detection of FTCs by real-time qRT-PCR might be of clinical importance during the postoperative follow-up for colorectal cancer patients.

Sequence-dependent effect of a cyclooxygenase-2 inhibitor on topoisomerase I inhibitor and 5-fluorouracil-induced cytotoxicity of colon cancer cells.

Selective cyclooxygenase-2 (COX-2) inhibitors have been found to induce anti-proliferative and apoptotic activity in many cancer cells. However, interaction between COX-2 inhibitors and other chemotherapeutic agents remains to be determined. We investigated the interactive effects of a selective COX-2 inhibitor, etodolac, in combination with 5-fluorouracil (5-FU) or SN-38 (active metabolite of irinotecan) on colon cancer cell lines, HT29 and SW620, in simultaneous and sequential administration schedules. Isobologram analysis demonstrated that etodolac in combination with 5-FU or SN-38 according to a simultaneous schedule resulted in only an additive effect; however, synergism was achieved in a sequential schedule. Apoptosis induction in both cell lines was also significantly increased after sequential treatment with etodolac followed by either 5-FU or SN-38 compared to that after simultaneous treatment with etodolac and either 5-FU or SN-38. Our study suggests apoptosis-inducing synergism resulted from administration of etodolac and either 5-FU or SN-38 sequentially, but not simultaneously.

Prognostic implications of the expression of erbB2, topoisomerase II alpha and thymidylate synthase in metastatic gastric cancer after fluorouracil-based therapy.

OBJECTIVE: This retrospective study aimed to ascertain the expression of erbB2 in relation to topoisomerase II alpha (T2 alpha) and thymidylate synthase (TS) markers in 30 consecutive metastatic gastric cancer patients with a specimen available for study. METHODS: All patients had been entered on consecutive chemotherapeutic clinical trials that were all 5-fluorouracil based. The specimens were evaluated by fluorescence in situ hybridization to ascertain erbB2 and T2 alpha gene amplification, and by immunohistochemical staining for T2 alpha and TS protein expression. RESULTS: erbB2 amplification was detected in 16.7% of specimens, with co-amplification of the T2 alpha gene in 40%, and 44% had undetectable TS protein expression. Kaplan-Meier survival curves showed significantly prolonged overall survival in patients with erbB2 and T2 alpha gene amplification, T2 alpha protein overexpression and absence of TS protein expression (P = 0.0011, P = 0.0048, P = 0.0061 and P = 0.0267, respectively, by log rank test). There was a positive correlation between erbB2 amplification and T2 alpha amplification, T2 alpha protein overexpression, and a trend towards absence of TS expression (P = 0.0001, P = 0.003 and P = 0.066 by Fisher's exact test). CONCLUSION: High dose fluorouracil/leucovorin-based chemotherapy may have the potential to reverse the adverse effects resulting from erbB2 gene amplification in gastric cancer.

Colon cancer cells with high invasive potential are susceptible to induction of apoptosis by a selective COX-2 inhibitor.

Cyclooxygenase-2 (COX-2) expression has been shown to correlate with the invasiveness of colon cancer cells. To further investigate this positive correlation and its possible therapeutic implications, a selective COX-2 inhibitor, etodolac, was tested on three variants of HT-29 colon cancer cell lines, HT-29/Inv1, HT-29/Inv2 and HT-29/Inv3, with graded increases of in vitro Matrigel invasive potential and COX-2 expression levels. HT-29 variants with higher invasive potential were found to be more sensitive to etodolac by in vitro growth inhibition assays, the estimated LD(50) being 0.5 mM for highly invasive HT-29/Inv2 and HT-29/Inv3 cells, 0.6 mM for slightly less invasive HT-29/Inv1, and 1.8 mM for the parental HT-29. Treatment of the highly invasive HT-29/Inv2 and Inv3 variants with as little as 0.1 mM etodolac in the growth medium produced signs of apoptosis, as detected by DNA fragmentation and TUNEL (terminal deoxynucleotidyl transferase dUTP-biotin nick end labeling) assay. In vivo experiments in SCID mice showed that etolodac inhibited the growth of subcutaneous tumors induced by HT-29/Inv3 cells significantly more than those by the parental HT-29 cells. These results suggest that COX-2 inhibitors have a potential role in prevention of tumor invasion in colon cancer patients.

A phase I study of weekly docetaxel, 24-hour infusion of high-dose fluorouracil/leucovorin and cisplatin in patients with advanced gastric cancer.

OBJECTIVES: To determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of both docetaxel and 5-fluorouracil (5-FU) when administered weekly in a regimen of docetaxel, 5-FU/leucovorin and cisplatin (DFLP) for 2 consecutive weeks every 3 weeks. PATIENTS AND METHODS: A total of 31 patients with chemo-naive, advanced adenocarcinoma of the stomach were enrolled in the study. Cisplatin and leucovorin dosages were fixed throughout the study at 30 and 300 mg/m2, respectively. 5-FU dosage was fixed at 1,600 mg/m2 while docetaxel was evaluated at weekly 1-hour infusion dosages of 30, 40 and 50 mg/m2 to determine the MTD. Cisplatin, 5-FU and leucovorin were administered together as a 24-hour continuous infusion following docetaxel. Weekly 5-FU dosages of 1,600, 2,000 and 2,400 mg/m2 were then evaluated after setting the docetaxel dosage at the MTD. RESULTS: A total of 95 chemotherapy cycles were administered, with a median of three cycles per patient. The MTD of docetaxel was defined at 40 mg/m2. At a docetaxel dosage of 50 mg/m2 per week, the dose-limiting events of grade 4 febrile neutropenia and grade 3 hypomagnesemia occurred. With fixation of docetaxel to 40 mg/m2, the DLT for 5-FU was found at 2,400 mg/m2 per week. This incurred grade 4 neutropenia such that the MTD of 5-FU was defined at 2,000 mg/m2. Grade 3/4 neutropenia occurred in 14 patients (45%), with 2 patients developing febrile neutropenia. Grade 2 and 3 hypomagnesemia and hypokalemia occurred in 9 (41%) and 4 (18%) patients, respectively, of the first 22 patients treated with a 24-hour infusion of cisplatin and 5-FU/leucovorin immediately following docetaxel. Following a change in the cisplatin administration schedule to a 3-hour infusion after 5-FU/leucovorin infusion, no such complications were observed in 9 subsequently treated patients. Grade 2 diarrhea was recorded in 11 patients (35%). Grade 2/3 asthenia occurred in 9 patients (30%), which resolved after correction of electrolyte disorders. Twenty-six patients were assessable for response analysis. There were 2 (7.8%) complete and 14 (53.8%) partial responses, with the overall response rate being 61.5% (95% confidence interval, 41.5-81.6%). Responses were observed at all dose levels. CONCLUSION: Two consecutive weeks of DFLP infusions every 3 weeks appear to be an active regimen with a tolerable toxicity profile in advanced gastric cancer. For further phase II studies, the recommended dose for this combination is 40 mg/m2 of docetaxel and 2,000 mg/m2 of 5-FU per week.

Palliative MEFLEP therapy in advanced pancreatic cancer: excellent response in a patient with Her-2/neu amplification.

INTRODUCTION: Patients with pancreatic cancer often present initially in advanced disease with many compromising factors, and yet they may still be responsive to chemotherapy. AIMS: The response of 23 patients with advanced pancreatic cancer to continuous infusion therapy was investigated. METHODOLOGY: From September 1995 to February 1998, 23 patients with advanced pancreatic cancer, many with compromising factors, were treated with a MEFLEP regimen: biweekly 24-hour infusions of etoposide, 5-fluorouracil, leucovorin, epirubicin, and cisplatin, all given through an infusion pump, plus megestrol acetate, 160 mg/d, taken daily. A total of 145 courses were given. Overall response rate was 21% (4/19) for assessable chemo-naive patients; median survival for all 23 patients was 6 months; 22% of patients were alive at 1 year; and a clinical response benefit was attained in 35%. RESULTS: Toxicity was manageable; grade 3 or 4 leukopenia occurred in 1 patient each, 1 patient had fever and grade 3 infection, and grade 3 and 4 hyperammonemic encephalopathy developed in 3 and 1 patients, respectively. All four of the latter patients recovered uneventfully within 2 days of initiation of therapy. Nine patients were evaluated by fluorescence in situ hybridization for the Her-2/neu oncogene, but for only one patient did amplification of the gene occur. She attained complete remission with treatment and lived for 26.7 months after diagnosis. CONCLUSION: Biweekly MEFLEP is an active and manageable regimen for patients with advanced pancreatic cancer with compromised clinical status.

Phase II and pharmacokinetic study of GL331 in previously treated Chinese gastric cancer patients.

PURPOSE: A phase II and pharmacokinetic study was designed to assess the efficacy and toxicity profile of an epidophyllotoxin analogue, GL331, in previously treated Chinese gastric cancer patients, with concurrent pharmacokinetic evaluation of the drug's metabolism. MATERIAL AND METHODS: GL331 was given at 200 mg/m(2) as a daily 3-h infusion for 5 days every 4 weeks. RESULTS: Enrolled in the study were 15 patients. One patient died from neutropenic sepsis before evaluation, one patient did not receive the full dose for reasons unrelated to GL331, nine patients had progressive disease with a median survival of 80 days, and five had stable disease with a median survival of 240 days. Grade 3 and 4 myelosuppression occurred in 10 of the 15 patients, with one death from neutropenic sepsis. This patient's peak GL331 concentration was 16.8 microg/ml, which was high compared to the mean peak drug concentration of 6+/-4.1 microg/ml. The mean systemic GL331 clearance was 12.1+/-7.2 l/h per m(2), much lower than 23.3+/-8.2 l/h per m(2) found in the phase I trial. Topoisomerase IIalpha was determined by immunohistochemistry and overexpression was detected in 3 of 11 specimens. CONCLUSIONS: GL331 was ineffective at this dose and schedule in this group of patients in spite of adequate blood levels of the drug.