Abstract P3-14-08: A randomized phase II trial comparing docetaxel plus cyclophosphamide with epirubicin plus cyclophosphamide followed by docetaxel as neoadjuvant chemotherapy for hormone receptor-negative breast cancer. Kanagawa breast oncology group (KBOG) 1101 study

Background: Taxane-based regimens have been developed and used widely to treat breast cancer. It has therefore become important to identify subgroups of patients in which anthracyclines are indispensable. Pathological response to neoadjuvant chemotherapy (NAC) predicts prognosis in hormone-negative subtypes. We therefore initiated a randomized phase II NAC study to compare a taxane with and without an anthracycline in these breast-cancer subtypes.

Aim: To determine the safety and activity of six cycles of docetaxel and cyclophosphamide (TC6) compared with 5-fluorouracil, epirubicin, and cyclophosphamide followed by docetaxel (FEC-D), and to examine the predictive factors for each regimen.

Methods: Eligibility criteria were operable hormone-receptor-negative breast cancer, age younger than 75 years and ECOG PS0-1. According to HER2 status, patients were randomly assigned to TC (75/600 mg/m2) every 3 weeks X 6 or FEC (500/100/500 mg/m2) every 3 weeks X 3 followed by D (100 mg/m2) every 3 weeks X 3. The primary endpoint was the rate of pathological complete response (pCR; grade 3). Triple-negative (TN) breast cancer was subdivided by cytokeratin 5/6 and epidermal growth factor receptor into basal- and non-basal subtypes. Secondary endpoints were safety, breast-conserving surgery, disease-free survival, overall survival, and predictive factors: Ki-67, p53, aldehyde dehydrogenase (ALDH) 1 and topoisomerase 2A by both immunohistochemistry and fluorescence in situ hybridization for each regimen.

Results: Ninety-seven of 103 patients were analyzed successfully (50 for FEC-D and 47 for TC6). Significantly more severe adverse events (grade 2) were observed in FEC-D-treated patients (poor appetite, nausea and vomiting: p = 0.001; febrile neutropenia: p = 0.016). The pCR rate tended to be higher in FEC-D-treated patients compared with TC6-treated patients (pCR: 36.0 vs. 25.5%, n.s.). FEC-D treatment was significantly more effective than TC6 in basal-type (p = 0.033) but not in non-basal and HER2 subtypes. ALDH1 was associated with resistance to both regimens (FEC-D: p = 0.047, TC6: p = 0.085)

Conclusions: TC6 was safer, but not more effective than FEC-D. TC6 was significantly less active than FEC-D in basal subtype, and equivalent to FEC-D in HER2 and non-basal subtypes. Concurrent use of trastuzumab with TC could thus represent a reasonable option for NAC in HER2-subtype patients. ALDH1 could provide a marker for novel strategies such as stem cell-based therapies for breast cancer. Analyses on pathological factors in surgical specimens after NAC will be presented at the meeting.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-08.

Abstract P6-06-20: Predictive factors for pathologic complete response and disease-free survival after neoadjuvant chemotherapy with trastuzumab: A multicenter retrospective observational study in patients with HER2-positive primary breast cancer (JBCRG-C03 study)

BACKGROUND:

Addition of trastuzumab to neoadjuvant chemotherapy (NAC) improved pathologic complete response (pCR) rate in HER2-positive breast cancer. Although recent trials have shown favorable prognosis with NAC plus trastuzumab, clinicopathological factors to predict the outcome have not been fully understood. The aim of this study was to investigate the survival after NAC with trastuzumab and to explore the predictive factors.

PATIENTS AND METHODS:

This is a multicenter retrospective observational study. Patients with HER2-positive primary breast cancer treated with NAC plus trastuzumab from 2001 to 2010 were identified from the institutional database. Primary end point was disease-free survival (DFS). pCR was defined as ypT0/is+ypN0. Kaplan-Meier method was used to estimate DFS. Logistic regression and proportional hazard analysis were used to identify clinicopathological factors to predict pCR and DFS, respectively.

RESULTS:

733 patients were included in the analysis (whole dataset). 425 were ER/PgR-negative (HR- dataset) and 306 were ER/PgR-positive (HR+ dataset). Radiation therapy was performed in 90% of lumpectomy and 31% of mastectomy. Hormonal therapy was performed in 84% of HR+ dataset. pCR rate was 45% in whole dataset, 60% in HR- dataset, and 34% in HR+ dataset. Table 1 showed the result of multivariate analysis for pCR in whole dataset. When HR+ and HR- dataset were analyzed separately, no definitive predictors for pCR were identified in multivariate analysis. Although the patients with pCR showed a significantly favorable prognosis than those without pCR at 3 years DFS, in whole dataset (93% vs 83%, p<0.0001) and HR- dataset (94% vs 80%, p<0.0001), there was no significant difference in HR+ dataset (89% vs 86%, p = 0.10). Different predictors were selected for DFS when multivariate analysis was conducted separately between HR- and HR+ dataset (Table 2).

CONCLUSIONS:

In this observational study, we clarified predictors for pCR and DFS in HER2-positive patients treated with neoadjuvant trastuzumab containing therapy based on tumor subtype. Our results may help us to predict the prognosis more precisely and to simulate the disease course.

Table 1) Multivariate logistic regression analysis for pCR in whole datasetFactorsOR95%CIp-valuePost- vs Pre-menopause1.50(1.05-2.15)0.026*cT1-2 vs cT3-41.72(1.16-2.59)0.008*ER/PgR-negative vs ER/PgR-positive3.32(2.30-4.82)<0.0001*Grade 3 vs 1-21.28(0.89-1.84)0.183

Table 2) Multivariate proportional hazard analysis for DFSFactors†HR95%CIp-valueWhole dataset   Pre- vs Post-menopause1.61(1.04-2.52)0.033*cN2-3 vs cN03.06(1.58-6.24)0.001*cN1 vs cN02.26(1.23-4.41)0.007*Grade 3 vs 1-21.87(1.20-2.97)0.006*non-pCR vs pCR1.90(1.18-3.13)0.008*HR- dataset   Pre- vs Post-menopause1.70(1.01-2.85)0.046*cT3-4 vs cT1-21.86(1.09-3.17)0.024*non-pCR vs pCR3.28(1.90-5.87)<0.0001*HR+ dataset   cN2-3 vs cN05.01(1.79-16.19)0.002*cN1 vs cN03.50(1.40-10.61)0.006*Grade 3 vs 1-22.95(1.52-5.87)0.001*†Only factors with statistical significance

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-20.

Abstract P2-12-13: Results of randomised controlled phase II study (KBCSG02 trial) of the efficiency of palonosetron, aprepitant, and dexamethasone for day1 with or without dexamethasone on days2 and 3

Background: Emesis is one of the major non-hematologic toxicity caused by chemotherapy. The control of Chemotherapy Induced Nausea and Vomiting (CINV) is conducted to a life lengthening. Recently, CINV is controlled by the second generation 5-HT3 receptor blocker (Palonosetron; PALO) and a NK-1 receptor antagonist (Aprepitant; APR). It has been shown that dexamethasone (DEX) with 5-HT3 receptor blocker improves acute/delayed CINV. However, it has not been determined the medication schedule of DEX with PALO and APR. The purpose of this study is evaluated the efficiency of palonosetron, aprepitant and dexamethasone for day1 with or without dexamethasone on days2 and 3.

Methods: Breast cancer patients who administered anthracyclin drug regimen have been eligible from April, 2011 to June, 2012. The patients were randomised to group A (PALO/APR/DEX one day) and group B (PALO/APR/DEX three days). Eighty patients was estimate as study samples. The primary endpoint was a complete response (CR) rate of vomiting, the secondary endpoint was a complete control (CC) rate of vomiting.

Distinct development of GABA system in the ventral and dorsal horns in the embryonic mouse spinal cord

In the adult brain, γ-amino butyric acid (GABA) is an inhibitory neurotransmitter, whereas it acts as an excitatory transmitter in the immature brain, and may be involved in morphogenesis. In the present study, we immunohistochemically examined the developmental changes in GABA signaling in the embryonic mouse cervical spinal cord. Glutamic acid decarboxylase and GABA were markers for GABA neurons. Vesicular GABA transporter was a marker for GABAergic and glycinergic terminals. Potassium chloride cotransporter 2 was a marker for GABAergic inhibition. We found five points: (1) In the ventral part, GABA neurons were divided into three groups. The first differentiated group sent commissural axons after embryonic day 11 (E11), but disappeared or changed their transmitter by E15. The second and third differentiated groups were localized in the ventral horn after E12, and sent axons to the ipsilateral marginal zone. There was a distal-to-proximal gradient in varicosity formation in GABAergic axons and a superficial-to-deep gradient in GABAergic synapse formation in the ventral horn; (2) In the dorsal horn, GABA neurons were localized after E13, and synapses were diffusely formed after E15; (3) GABA may be excitatory for several days before synapses formation; (4) There was a ventral-to-dorsal gradient in the development of GABA signaling. The GABAergic inhibitory network may develop in the ventral horn between E15 and E17, and GABA may transiently play crucial roles in inhibitory regulation of the motor system in the mouse fetus; (5) GABA signaling continued to develop after birth, and GABAergic system diminished in the ventral horn.

GPER1/GPR30 activation improves neuronal survival following global cerebral ischemia induced by cardiac arrest in mice

Female sex steroids, particularly estrogens, contribute to the sexually dimorphic response observed in cerebral ischemic outcome, with females being relatively protected compared to males. Using a mouse model of cardiac arrest and cardiopulmonary resuscitation (CA/CPR), we previously demonstrated that estrogen neuroprotection is mediated in part by the estrogen receptor β, with no involvement of estrogen receptor α. In this study we examined the neuroprotective effect of the novel estrogen receptor, G-protein coupled estrogen receptor 1 (GPER1/GPR30). Male mice administered the GPR30 agonist G1 exhibited significantly reduced neuronal injury in the hippocampal CA1 region and striatum. The magnitude of neuroprotection observed in G1 treated mice was indistinguishable from estrogen treated mice, implicating GPR30 in estrogen neuroprotection. Real-time quantitative RT-PCR indicates that G1 treatment increases expression of the neuroprotective ion channel, small conductance calcium-activated potassium channel 2. We conclude that GPR30 agonists show promise in reducing brain injury following global cerebral ischemia.

Expression of uPAR mRNA in peripheral blood is a favourite marker for metastasis in gastric cancer cases

Urokinase-type plasminogen activator receptor (uPAR) plays a central role in the plasminogen activation cascade and participates in extracellular matrix degradation, cell migration and invasion. We evaluated the expression level of uPAR mRNA and the presence of isolated tumour cells (ITCs) in bone marrow (BM) and peripheral blood (PB) in gastric cancer patients and clarified its clinical significance. We assessed specific uPAR mRNA expression by quantitative real-time reverse transcriptase- polymerase chain reaction (RT–PCR) in BM and PB in 846 gastric cancer patients as well as three epithelial cell markers, carcinoembryonic antigen (CEA), cytokeratin (CK)-19 and CK-7. The uPAR mRNA expression in bone marrow and peripheral blood expressed significantly higher than normal controls (P<0.0001). The uPAR mRNA in BM showed concordant expression with the depth of tumour invasion, distant metastasis, and the postoperative recurrence (P=0.015, 0.044 and 0.010, respectively); whereas in PB, we observed more intimate significant association between uPAR expression and clinicopathologic variables, such as depth of tumour invasion, the distant metastasis, the venous invasion and the clinical stage (P=0.009, 0.002, 0.039 and 0.008, respectively). In addition, the uPAR mRNA expression in PB was an independent prognostic factor for distant metastasis by multivariate analysis. We disclosed that it was possible to identify high-risk patients for distant metastasis by measuring uPAR mRNA especially in peripheral blood at the timing of operation in gastric cancer patients.

Outcome of risk-based therapy for infant acute lymphoblastic leukemia with or without an MLL gene rearrangement, with emphasis on late effects: a final report of two consecutive studies, MLL96 and MLL98, of the Japan Infant Leukemia Study Group

We evaluated the efficacy of a treatment strategy in which infants with acute lymphoblastic leukemia (ALL) were stratified by their MLL gene status and then assigned to different risk-based therapies. A total of 102 patients were registered on two consecutive multicenter trials, designated MLL96 and MLL98, between 1995 and 2001. Those with a rearranged MLL gene (MLL-R, n=80) were assigned to receive intensive chemotherapy followed by hematopoietic stem cell transplantation (HSCT), while those with germline MLL (MLL-G, n=22) were treated with chemotherapy alone. The 5-year event-free survival (EFS) rate for all 102 infants was 50.9% (95% confidence interval, 41.0-60.8%). The most prominent late effect was growth impairment, observed in 58.9% of all evaluable patients in the MLL-R group. This plan of risk-based therapy appears to have improved the overall prognosis for infants with ALL, compared with previously reported results. However, over half the events in patients with MLL rearrangement occurred before the instigation of HSCT, and that HSCT-related toxic events comprised 36.3% (8/22) of post-transplantation events, suggesting that further stratification within the MLL-R group and the development of more effective early-phase intensification chemotherapy will be needed before the full potential of this strategy is realized.

Prophylactic fresh frozen plasma may prevent development of hepatic VOD after stem cell transplantation via ADAMTS13-mediated restoration of von Willebrand factor plasma levels

We initially conducted a multicenter, randomized trial (n=43), and subsequently a questionnaire study (n=209) of participating hospitals, to evaluate whether infused fresh frozen plasma (FFP) could prevent the occurrence of hepatic veno-occlusive disease (VOD) after stem cell transplantation (SCT). Forty-three patients were divided into two groups: 23 receiving FFP infusions and 20 not receiving it. VOD developed in three patients not receiving FFP. Plasma von Willebrand factor (VWF) antigen levels were lower at days 0, 7 and 28 after SCT in patients receiving FFP than in those not receiving it, whereas plasma ADAMTS13 activity (ADAMTS13:AC) did not differ between them. Plasma VWF multimer (VWFM) was demonstrated to be defective in the high approximately intermediate VWFM during the early post-SCT phase, but there was a significant increase in high VWFM just before VOD onset. This suggests that a relative enzyme-to-substrate (ADAMTS13/high-VWFM) imbalance is involved in the pathogenesis of VOD. To strengthen this hypothesis, the incidence of VOD was apparently lower in patients receiving FFP infusions than in those not receiving it (0/23 vs 3/20) in the randomized trial. Further, the results combined with the subsequent questionnaire study (0/36 vs 11/173) clearly showed the incidence to be statistically significant (0/59 vs 14/193, P=0.033).

Identification of the high-risk group for metastasis of gastric cancer cases by vascular endothelial growth factor receptor-1 overexpression in peripheral blood

Identification of an isolated tumour cell with metastatic ability is important for predicting the recurrence and prognosis of gastric cancer. A biological marker for evaluating the metastatic ability of gastric cancer cells has not yet been identified. We assessed vascular endothelial growth factor receptor-1 mRNA expression by quantitative real-time reverse transcriptase-polymerase chain reaction. Vascular endothelial growth factor receptor-1 mRNA in peripheral blood was more highly expressed in perioperative metastasis-positive and postoperative recurrence cases than in normal control cases, early cancer cases and nonmetastatic advanced cancer cases. The peripheral blood vascular endothelial growth factor receptor-1 mRNA-positive group was associated with advanced clinical stage, deep invasion beyond the muscularis propria, lymphatic involvement, vascular involvement, lymph node metastasis, positive peritoneal lavage cytology, preoperative metastasis and postoperative recurrence. Flow cytometry analysis disclosed that vascular endothelial growth factor receptor-1 expressing cells in the peripheral blood were more abundant in cancer cases with metastases than in cases without metastases. Our data suggest that the amount of positive cells may provide information on the clinical features of gastric cancer, especially in regard to gastric cancer metastasis.

Partial hepatectomy and subsequent radiation facilitates engraftment of mouse embryonic stem cells in the liver

For liver-targeted regenerative medicine, embryonic stem (ES) cell-derived hepatocyte-like cells proffer great expectation. In vitro exposure to a combination of various growth factors, such as hepatocyte growth factor and fibroblast growth factor-4, as well as cytokines, leads to differentiation of ES cells into hepatocyte-like cells. We sought to determine the in vivo environment that allowed engraftment of ES cells transplanted to the liver. Thus, we examined the effect of partial hepatectomy (50%) (PHT) and subsequent radiation (RT) of the male Balb/c mouse host liver on ES cell engraftment. ES cells (5 x 10(6)) derived from 129Sv mice were transplanted into the residual liver. The controls were ES cells transplanted into a normal liver. Bromo-deoxy-residine (BrdU)-uptake was performed to evaluate the effect of hepatectomy and RT on hepatocyte regeneration. Mouse ES cells engrafted, forming teratomas in the normal liver without showing any mononuclear infiltration. A liver modified by PHT and RT facilitated engraftment of mouse ES cells compared with a normal liver. Hepatic RT significantly suppressed hepatocytic uptake of BrdU.

Transduction of human islets with the lentiviral vector

Establishment of an efficient gene delivery system for human pancreatic beta cells is important for the development of diabetes-targeted cell therapies. The human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vector is well documented to be an effective gene transfer tool for various types of cells. Thus, we examined the efficiency of lentivirus-mediated gene delivery for human islets. Human islets were isolated using defined protocols for enzymatic dissociation and purification using discontinuous Ficoll gradients with a refrigerated Cobe 2991 machine. Isolated islets were shipped to Japan, cryopreserved for 3 months, and then subjected to transduction. A vesicular stomatitis virus G-protein (VSV-G)-pseudotyped lentiviral vector LtV-NLS/LacZ was produced in 293T cells under the Fugene6 method. 804G extracellular matrices were applied for monolayer formation of islets. Detection of NLS/LacZ expression was performed using X-gal staining. Lentiviral transduction was effective in these monolayer islets.

Lack of clinical utility of minimal residual disease detection in allogeneic stem cell recipients with childhood acute lymphoblastic leukemia: multi-institutional collaborative study in Japan

The clinical utility of minimal residual disease (MRD) measurements following allogeneic stem cell transplantation (SCT) in childhood ALL is controversial. We therefore performed a multi-institutional study of MRD in bone marrow samples taken before SCT and at 1, 3, 6 and 12 months after SCT. Case-specific clonal rearrangements of IgH and TCR genes and expression levels of Wilms' tumor 1 (WT1) mRNA were determined by PCR or RT-PCR methods. In total, 95 cases met all criteria for analysis of informative IgH/TCR markers and quantitative WT1 mRNA expression levels. During the 2-year (median 414 days) study period, 20 patients relapsed. Although the proportion of patients with a positive IgH/TCR result before SCT was significantly reduced at 1 month after treatment (P<0.001), attesting the efficacy of SCT, serial measurements of IgH/TCR rearrangements did not correlate with leukemic relapse. Clonal switch was demonstrated in 11 of the 14 patients with bone marrow relapse, indicating that the poor predictive power of the MRD assay most likely reflected the loss of PCR targets. WT1 expression was not related to either MRD detection by IgH/TCR assays or to clinical leukemic relapse. The clinical value of serial MRD monitoring would be limited in ALL patients undergoing SCT.

[First successful clinical application of tissue engineered blood vessel]

With this tissue engineering (TE) technique, the peripheral pulmonary artery was successfully reconstructed, using the patient's own venous cells in a 4-year-old girl, 2 years after Fontan procedure. A 4-year-old girl was given a diagnosis of single right ventricle, double-outlet right ventricle and pulmonary atresia. She underwent left modified Blalock-Taussig shunt at a month old, pulmonary artery angioplasty at a year and 3 months old, and bidirectional cavopulmonary shunt at 2 years and a month old. She underwent again pulmonary artery angioplasty and Fontan operation at 3 years and 3 months. An angiographical examination 7 months after the operation revealed total occlusion of the right intermediate pulmonary artery. TE technique using autologous cells was indicated. The application of this procedure was approved by the ethical committee in Tokyo Women's Medical University. The patient's parents were thoroughly informed and signed a consent form. Approximately 2 cm of the peripheral vein was explanted under sterile conditions. The tissue was minced, placed in tissue culture dishes and cultured at 37 degrees C, 100% humidity and a 5% CO2 atmosphere for almost a month. The number of cells substantially increased to reach 12 millions for almost a month. The culture medium was changed every 3 days. The polymer tube that served as a scaffold for cells was composed of the copolymer of PCL-PLA (50:50) with reinforcement by woven PGA. The polymer conduit, 10 mm in diameter, 20 mm in length and 1 mm in thickness, was designated to biodegradate within 8 weeks. The number of seeded cells was approximately a million/cm2. The graft transplantation was performed 10 days after seeding cells. The occlusive right intermediate pulmonary artery was reconstructed with the TE vessel graft under extracorporeal circulation with a pump-oxygenator. The patient followed a satisfactory postoperative course. The postoperative angiography demonstrated that the graft was not constricted and dilated but that it preserved good patency. Long-term follow-up are necessary. We plan to continue to use the TE technique using autologous cells in the low pressure system like venous or pulmonary circulation. Because our results even in early experimental phase were valuable and promising, we believe that the TE approach may play an important role in the near future as an another alternative, together with transplantation and artificial organ, especially in the field of cardiovascular surgery that mostly needs replants.

Superior outcome of infant acute myeloid leukemia with intensive chemotherapy: results of the Japan Infant Leukemia Study Group

This study analyzed data on 35 infants with acute myeloid leukemia (AML) who were treated with intensive chemotherapy between 1995 and 1998 in Japan. The incidence of boys, younger age (< 6 months old), and hyperleukocytosis at onset was high in patients with the M4/M5 subtype (n = 23) in the French-American-British classification, compared with the non-M4/M5 subtype (n = 12). Thirteen (56%) and 16 (70%) patients with the M4/M5 subtype also showed 11q23 translocations and MLL gene rearrangements, respectively, whereas only one patient with the non-M4/M5 subtype had this rearrangement. All 35 patients were treated with the ANLL91 protocol consisting of etoposide, high-dose cytarabine, and anthracyclines. Overall survival and the event-free survival (EFS) rates at 3 years of all patients were 76% (95% confidence interval [CI], 61.3%-90.7%) and 72% (95% CI, 56.4%-87.9%), respectively. EFS showed no significant difference between 2 subgroups divided by age, gender, presence of the MLL gene rearrangements, and white blood cell count at onset; EFS in patients with the M4/M5 subtype tended to be better than those with the non-M4/M5 subtype. Although all 6 patients who underwent allogeneic stem cell transplantation (SCT) have been in complete remission, no benefit of SCT was confirmed. These findings suggest that the intensive chemotherapy with the ANLL91 protocol might have been responsible for the observed good outcome of infant AML, even without SCT. The presence of the MLL gene rearrangements or the age at onset had no impact on the outcome of infant AML.