Seiji Isonishi

Dose-dense paclitaxel once a week in combination with carboplatin every 3 weeks for advanced ovarian cancer: a phase 3, open-label, randomised controlled trial

BACKGROUND Paclitaxel and carboplatin given every 3 weeks is standard treatment for advanced ovarian carcinoma. Attempts to improve patient survival by including other drugs have yielded disappointing results. We compared a conventional regimen of paclitaxel and carboplatin with a dose-dense weekly regimen in women with advanced ovarian cancer. METHODS Patients with stage II to IV epithelial ovarian cancer, fallopian tube cancer, or primary peritoneal cancer were eligible for enrolment in this phase 3, open-label, randomised controlled trial at 85 centres in Japan. Patients were randomly assigned by computer-generated randomisation sequence to receive six cycles of either paclitaxel (180 mg/m(2); 3-h intravenous infusion) plus carboplatin (area under the curve [AUC] 6 mg/mL per min), given on day 1 of a 21-day cycle (conventional regimen; n=320), or dose-dense paclitaxel (80 mg/m(2); 1-h intravenous infusion) given on days 1, 8, and 15 plus carboplatin given on day 1 of a 21-day cycle (dose-dense regimen; n=317). The primary endpoint was progression-free survival. Analysis was by intention to treat (ITT). This trial is registered with ClinicalTrials.gov, number NCT00226915. FINDINGS 631 of the 637 enrolled patients were eligible for treatment and were included in the ITT population (dose-dense regimen, n=312; conventional regimen, n=319). Median progression-free survival was longer in the dose-dense treatment group (28.0 months, 95% CI 22.3-35.4) than in the conventional treatment group (17.2 months, 15.7-21.1; hazard ratio [HR] 0.71; 95% CI 0.58-0.88; p=0.0015). Overall survival at 3 years was higher in the dose-dense regimen group (72.1%) than in the conventional treatment group (65.1%; HR 0.75, 0.57-0.98; p=0.03). 165 patients assigned to the dose-dense regimen and 117 assigned to the conventional regimen discontinued treatment early. Reasons for participant dropout were balanced between the groups, apart from withdrawal because of toxicity, which was higher in the dose-dense regimen group than in the conventional regimen group (n=113 vs n=69). The most common adverse event was neutropenia (dose-dense regimen, 286 [92%] of 312; conventional regimen, 276 [88%] of 314). The frequency of grade 3 and 4 anaemia was higher in the dose-dense treatment group (214 [69%]) than in the conventional treatment group (137 [44%]; p<0.0001). The frequencies of other toxic effects were similar between groups. INTERPRETATION Dose-dense weekly paclitaxel plus carboplatin improved survival compared with the conventional regimen and represents a new treatment option in women with advanced epithelial ovarian cancer. FUNDING Bristol-Myers Squibb.

Long-term results of dose-dense paclitaxel and carboplatin versus conventional paclitaxel and carboplatin for treatment of advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer (JGOG 3016): a randomised, controlled, open-label trial

BACKGROUND The primary analysis of the JGOG 3016 trial showed that a dose-dense paclitaxel and carboplatin regimen significantly improves progression-free and overall survival compared with the conventional regimen as first-line chemotherapy for patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer. We report the long-term follow-up results for survival. METHODS This randomised controlled trial was done at 85 centres in Japan. Patients with stage II-IV ovarian cancer were randomly assigned to receive conventional treatment (carboplatin area under the curve [AUC] 6 mg/mL per min and paclitaxel 180 mg/m(2) on day 1) or dose-dense treatment (carboplatin AUC 6 mg/mL per min on day 1 and paclitaxel 80 mg/m(2) on days 1, 8, and 15). The treatments were repeated every 3 weeks for six cycles; responding patients had three additional cycles. The randomisation was done centrally by telephone or fax, stratified by residual disease, stage, and histological type. The primary endpoint was progression-free survival; overall survival was a secondary endpoint. Long-term information on adverse events was not collected. Efficacy analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00226915. FINDINGS 637 patients were enrolled, of whom 631 were analysed (312 assigned to the dose-dense regimen, 319 to the conventional regimen). Median follow-up was 76·8 months (IQR 68·9-85·6). Median progression-free survival was significantly longer in the dose-dense treatment group than in the conventional treatment group (28·2 months [95% CI 22·3-33·8] vs 17·5 months [15·7-21·7]; hazard ratio [HR] 0·76, 95% CI 0·62-0·91; p=0·0037). Median overall survival was 100·5 months (95% CI 65·2-∞) in the dose-dense treatment group and 62·2 months (52·1-82·6) in the conventional treatment group (HR 0·79, 95% CI 0·63-0·99; p=0·039). INTERPRETATION Dose-dense treatment offers better survival than conventional treatment and is a potential new standard of care for first-line chemotherapy for patients with advanced epithelial ovarian cancer.

Heat shock protein 27 was up-regulated in cisplatin resistant human ovarian tumor cell line and associated with the cisplatin resistance

To understand the molecular basis for failure of cisplatin (CDDP) based chemotherapy, we compared gene expressions between CDDP sensitive and resistant ovarian tumor cell line, 2008 and 2008/C13*5.25, by mRNA differential display. We detected both up-regulated and down-regulated bands in the resistant cell and found some of them to be positive on Northern blotting. DNA sequencing revealed one to be mitochondrial heat shock protein 75. We found that HSP27 and HSP70 were also up-regulated in the resistant cell by Western blotting. Further, transient transfection with the HSP27 sense gene made the sensitive cell more resistant, while transient transfection with the antisense gene made it more sensitive.

Allelic imbalance and mutations of the PTEN gene in ovarian cancer

The PTEN/MMAC1/TEP1 tumor‐suppressor gene, which maps to chromosome 10q23.3, is mutated and homozygously deleted in a variety of human tumors, including endometrioid‐type ovarian tumors. We examined 33 primary ovarian cancers and 3 ovarian borderline tumors for allelic imbalance (AI) of the 10q23.3 region using 5 polymorphic markers, including an insertion/deletion‐type polymorphic marker identified in intron 4 of the PTEN gene. AI at one or more loci was detected in 12 of 31 (39%) informative ovarian cancers and none of 3 ovarian borderline tumors. The commonly deleted region was mapped between the D10S215 and D10S541 loci, including the PTEN locus. Moreover, the incidence of AI at the PTEN locus (38%) was the highest among the 5 loci examined. Therefore, we searched for mutations in the entire coding region of the PTEN gene by PCR‐SSCP and sequencing analyses in these tumors and 7 ovarian cancer cell lines. Mutations were detected in 3 of the 33 (9%) ovarian cancers: 2 cases with double mutations and 1 case with a mutation on 1 allele accompanied by deletions on both alleles in the poly T tract preceding the splice acceptor site in intron 7. An intragenic deletion was detected in 1 of the 7 (14%) ovarian cancer cell lines. PTEN mutations were detected not only in the endometrioid type but also in the serous and mucinous types of ovarian cancer. However, PTEN was not mutated in the 12 tumors that showed AI of the PTEN locus. Our results suggest that the PTEN gene plays an important role in the development of a subset but diverse histological types of ovarian tumors. However, it is possible that another tumor‐suppressor gene in the close vicinity of the PTEN gene is also inactivated by AI of the 10q23.3 region. Int. J. Cancer 85:160–165, 2000. ©2000 Wiley‐Liss, Inc.

Randomized phase III trial of irinotecan plus cisplatin compared with paclitaxel plus carboplatin as first-line chemotherapy for ovarian clear cell carcinoma: JGOG3017/GCIG trial

PURPOSE Clear cell carcinoma (CCC) is a rare histologic subtype that demonstrates poor outcomes in epithelial ovarian cancer. The Japanese Gynecologic Oncology Group conducted the first randomized phase III, CCC-specific clinical trial that compared irinotecan and cisplatin (CPT-P) with paclitaxel plus carboplatin (TC) in patients with CCC. PATIENTS AND METHODS Six hundred sixty-seven patients with stage I to IV CCC of the ovary were randomly assigned to receive irinotecan 60 mg/m(2) on days 1, 8, and 15 plus cisplatin 60 mg/m(2) on day 1 (CPT-P group) every 4 weeks for six cycles or paclitaxel 175 mg/m(2) plus carboplatin area under the curve 6.0 mg/mL/min on day 1 every 3 weeks for six cycles (TC group). The primary end point was progression-free survival. Secondary end points were overall survival, overall response rate, and adverse events. RESULTS Six hundred nineteen patients were clinically and pathologically eligible for evaluation. With a median follow-up of 44.3 months, 2-year progression-free survival rates were 73.0% in the CPT-P group and 77.6% in TC group (hazard ratio, 1.17; 95% CI, 0.87 to 1.58; P = .85). Two-year overall survival rates were 85.5% with CPT-P and 87.4% with TC (hazard ratio, 1.13; 95% CI, 0.80 to 1.61; one-sided P = .76). Grade 3/4 anorexia, diarrhea, nausea, vomiting, and febrile neutropenia occurred more frequently with CPT-P, whereas grade 3/4 leukopenia, neutropenia, thrombocytopenia, peripheral sensory neuropathy, and joint pain occurred more frequently with TC. CONCLUSION No significant survival benefit was found for CPT-P. Both regimens were well tolerated, but the toxicity profiles differed significantly. Treatment with existing anticancer agents has limitations to improving the prognosis of CCC.

Allelic imbalance in chromosome band 18q21 and SMAD4 mutations in ovarian cancers

Recently, three candidate tumor suppressor genes, SMAD2 (MADR2/JV18–1), SMAD4 (DPC4), and DCC, were identified in chromosome band 18q21. We examined allelic imbalance (AI) in 18q21 using six polymorphic microsatellite markers in 38 primary ovarian cancers and four ovarian borderline tumors. AI at one or more loci was detected in 15 of 37 (41%) informative ovarian cancers and in none of the four borderline tumors. Frequent AI was detected at the D18S46 (31%) and D18S474 (36%) loci, which were adjacent to the SMAD4 gene, and at the D18S69 (33%) locus, which was telomeric to the DCC gene. Therefore, we searched for mutations of the SMAD4 gene in 42 primary tumors and eight cell lines by PCR‐SSCP and sequencing analyses. Missense mutations were detected in two ovarian tumors and three ovarian cancer cell lines, whereas silent mutation was detected in a primary ovarian cancer. These results suggest that there are at least two tumor suppressor genes on chromosome arm 18q and that SMAD4 is of importance in ovarian tumorigenesis. Genes Chromosomes Cancer 24:264–271, 1999.

Signaling and drug sensitivity.

Even though alterations in receptor and nonreceptor kinases are involved in the development of human cancer, many cancer cell lines still retain their responsiveness to growth factors. We have investigated the hypothesis that cellular signaling events regulate the sensitivity of cancer cells to chemotherapeutic agents. In 2008 human ovarian carcinoma cells, activation of a number of different transduction pathways resulted in a 2 to 4-fold increase in the sensitivity to cisplatin. These signaling events include pathways activated by the epidermal growth factor (EGF) receptor, tumor necrosis factor α (TNFα) receptor, bombesin receptor, protein kinase A (PKA), and protein kinase C (PKC). Enhanced sensitivity to chemotherapeutic agents is presumed to be mediated by phosphorylation of critical target protein(s). β-tubulin has been identified as one such target for the protein kinase A signaling cascade. For other signal transduction pathways the key substrates that regulate drug sensitivity have not yet been identified. Recent work has shown that DNA damaging agents activate signaling cascades one of which involves the Src, Ras, and Raf proteins as intermediates and results in induction of a number of genes, including c-fos, c-jun, and the growth arrest and DNA damage??inducible (gadd) genes. This signaling cascade has been shown to involve activation of protein kinase C and to have a protective function. With the growing understanding of how signaling events relate to damage response and drug sensitivity, new and potentially useful strategies for modulating drug sensitivity are evolving.

Depletion of protein kinase C (PKC) by 12- O -tetradecanoylphorbol-13-acetate (TPA) enhances platinum drug sensitivity in human ovarian carcinoma cells

Down-regulation of protein kinase C (PKC) by 12- O -tetradecanoylphorbol-13-acetate (TPA) enhances the sensitivity of human ovarian carcinoma 2008 cells to various types of platinum compounds such as cisplatin (DDP), carboplatin and (–)-(R)-2-aminomethylpyrrolidine (1,1-cyclobutanedicarboxylato)-platinum(II) monohydrate (DWA) by a factor of two- to threefold. TPA enhanced the sensitivity of the DDP-resistant 2008/C13*5.25 subline to each of these three drugs to the same extent as for the 2008 cells. The extent of PKC down-regulation and drug sensitization depended on the duration of TPA exposure; maximum effect was achieved with a 48 h pretreatment. Sensitization was TPA concentration-dependent and was maximal at 0.05 μM TPA. 2008 cells expressed only the PKCα and PKCζ isoforms. Western blot analysis revealed that whereas the expression of PKCα was reduced by TPA the level of PKCζ was not affected. These results suggest that PKCα is the isotype responsive to TPA in these cells and that platinum drug sensitivity can be modulated by this isoform alone. In parallel to its effect on PKCα, TPA decreased cellular glutathione content by 30 ± 3 (standard deviation (s.d.) % in 2008 cells and by 41 ± 3 (s.d.) % in 2008/C13*5.25 cells. TPA also increased accumulation of DDP and DWA by 70%, although this effect was limited to the 2008/C13*5.25 cells. TPA rendered 2008 and 2008/C13*5.25 cells resistant to cadmium chloride by a factor of 3.7 and 3.6-fold respectively, suggesting a significant increase in cellular metallothionein content. Although the mechanism of TPA induced sensitization is not yet fully understood, this study points to a central role for PKCα in modulating platinum drug sensitivity.

Side population is increased in paclitaxel-resistant ovarian cancer cell lines regardless of resistance to cisplatin

OBJECTIVES In recent years, cancer stem cells (CSCs) have been reported to be correlated with chemoresistance and may also be enriched in side populations (SPs). In this study, the relationship between resistance to paclitaxel (PTX) and cisplatin (CDDP) and side populations was examined in three parental PTX- and CDDP-sensitive ovarian cancer cell lines (2008, KF28, and TU-OM-1) and several other cell lines derived from these as well as the additional effects of interferon-alpha (INF-α). METHODS SP of three different parental cell lines and PTX- and/or CDDP-resistant cell lines derived from these was analyzed with flow cytometry. The expression of ABCB1 and ABCG2 in KF28 and its derived cell lines was examined. Additional cell-death effect of INF-α with PTX was also examined. RESULTS In the three parental cell lines and the PTX-sensitive cell lines derived from these lines, SP was very low. Conversely, in PTX-resistant cell lines, regardless of CDDP resistance, SP increased. ABCB1 was strongly expressed in the PTX-resistant cells, but not in their parental lines, which are sensitive to PTX. While INF-α showed only slight enhancement of the cell-death effect of PTX in PTX-sensitive cells, INF-α itself strongly induced apoptosis in PTX-resistant cells regardless of PTX concentration. CONCLUSIONS The SP could be correlated with resistance to PTX. SP could be a target of INF-α, and resistance to PTX might be overcome by INF-α.

Alpha-fetoprotein (AFP)-producing ovarian tumor in an elderly woman

Apart from typical yolk sac tumors, ovarian tumors with elevated alfa-fetoprotein (AFP) are uncommon and the differential diagnosis needs to consider the hepatoid pattern of a yolk sac tumor, hepatocellular carcinoma metastatic to the ovary, hepatoid carcinoma, and other epithelial ovarian tumors. We report here an AFP-producing ovarian tumor with uncertain pathological diagnosis, which was extremely responsive to chemotherapy. A 59-year-old Japanese woman presented with lower abdominal distension and was found to have a left ovarian mass on pelvic examination and magnetic resonance imaging (MRI) scan. Laboratory tests showed serum AFP, 73 687 ng/ml; carbohydrate antigen 125 (CA125), 1599 U/ml; and carcinoembryonic antigen (CEA), 13.9 ng/ml. Total hysterectomy with bilateral salpingo-oophorectomy, partial omentectomy, and low anterior resection of the rectum was performed, without any residual macroscopic tumor. Microscopically, the tumor was characterized by a hepatoid carcinomatous component composed of solid sheets of large eosinophilic cells with pleomorphic nuclei. The pathological stage was pT2N0M0. Tumor cells were diffusely immunoreactive for AFP and cytokeratin (CAM5.2), but monoclonal CEA and CA19-9 were focally positive in the cytoplasm, while CA125 was negative. The patient was treated postoperatively with three cycles of chemotherapy consisting of bleomycin, etoposide, and cisplatin; with this regimen, serum AFP decreased to 16 ng/ml from 12 600 ng/ml just before the initiation of chemotherapy. The patient received secondary cytoreductive surgery of systemic lymphadenectomy, which revealed no evidence of residual tumor.