Tricritical point and wing structure in the itinerant ferromagnet UGe₂

Precise resistivity measurements on the ferromagnetic superconductor UGe2 under pressure p and magnetic field H reveal a previously unobserved change of the anomaly at the Curie temperature. Therefore, the tricritical point (TCP) where the paramagnetic-to-ferromagnetic transition changes from a second order to a first order transition is located in the p-T phase diagram. Moreover, the evolution of the TCP can be followed under the magnetic field in the same way. It is the first report of the boundary of the first order plane which appears in the p-T-H phase diagram of weak itinerant ferromagnets. This line of critical points starts from the TCP and will terminate at a quantum critical point. These measurements provide the first estimation of the location of the quantum critical point in the p-H plane and will inspire similar studies of the other weak itinerant ferromagnets.

Similarity of the Fermi surface in the hidden order state and in the antiferromagnetic state of URu₂Si₂

Shubnikov-de Haas measurements of high quality URu2Si2 single crystals reveal two previously unobserved Fermi surface branches in the so-called hidden order phase. Therefore, about 55% of the enhanced mass is now detected. Under pressure in the antiferromagnetic state, the Shubnikov-de Haas frequencies for magnetic fields applied along the crystalline c axis show little change compared with the zero pressure data. This implies a similar Fermi surface in both the hidden order and antiferromagnetic states, which strongly suggests that the lattice doubling in the antiferromagnetic phase due to the ordering vector Q(AF)=(001) already occurs in the hidden order. These measurements provide a good test for existing or future theories of the hidden order parameter.

Field re-entrant hidden-order phase under pressure in URu2Si2

We succeeded in growing high quality single crystals of URu(2)Si(2) and performed thermal expansion measurements under pressure. Applying a magnetic field along the [001] direction in the tetragonal structure, the so-called hidden-order phase reappears after the suppression of the antiferromagnetic phase above the critical pressure P(x). We determined the pressure-temperature-field phase diagram for the paramagnetic, hidden-order and antiferromagnetic states for the [Formula: see text] direction. We also present the temperature dependence of the upper critical field H(c2) for [Formula: see text] and [100] determined by the AC specific heat measurements, corresponding to the bulk superconductivity in a high quality single crystal.

Effects of third-line chemotherapy for women with recurrent ovarian cancer who received platinum/taxane regimens as first-line chemotherapy

PURPOSE

At present, it remains unclear whether the third-line chemotherapy has clinical benefit. In this study, we retrospectively evaluated the effect of third-line chemotherapy.

METHODS

We reviewed the medical records of 40 women with recurrent epithelial ovarian cancer (EOC) who received third-line chemotherapy after platinum/taxan regimens as first line chemotherapy.

RESULTS

In the first recurrence, 23 cases were platinum-sensitive and 17 cases were platinum-resistant. The cases for which the treatment-free interval from second-line chemotherapy (TFI) was a 3 months had a higher non-PD rate than those with TFI < 3 months (86% vs 33%, p = 0.002). In addition, the median overall survival (OS) was longer for TFI > or = 3 months than for TFI < 3 months (1195 days vs 235 days, p = 0.004). Finally, TFI was an independent significant prognostic factor by univariate (HR 3.28, p = 0.006) and multivariate (HR 3.21, p = 0.018) proportional hazard tests.

CONCLUSION

TFI from second-line chemotherapy may predict a survival benefit of third-line chemotherapy.

Superconducting and normal phases of FeSe single crystals at high pressure

We report on the synthesis of superconducting single crystals of FeSe and their characterization by x-ray diffraction, magnetization and resistivity. We have performed ac susceptibility measurements under high pressure in a hydrostatic liquid argon medium up to 14 GPa and we find that T(C) increases up to 33-36 K in all samples, but with slightly different pressure dependences on different samples. Above 12 GPa no traces of superconductivity are found in any sample. We have also performed a room temperature high pressure x-ray diffraction study up to 12 GPa on a powder sample, and we find that, between 8.5 and 12 GPa, the tetragonal PbO structure undergoes a structural transition to a hexagonal structure. This transition results in a volume decrease of about 16% and is accompanied by the appearance of an intermediate, probably orthorhombic, phase.

Use of amplification of the 8q24 and 20q11–13 loci to predict progression-free survival of advanced epithelial ovarian cancer patients receiving standard therapy

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Background: The purpose of this study was to identify genes that predict the progression free survival (PFS) of advanced epithelial ovarian cancer (aEOC) receiving standard therapy. Methods: We performed expression analysis using GeneChip (Human Genome U133 plus 2.0 Array) in aEOC cells produced by laser-based microdissection. Thirty three aEOC patients (stage IIc: 4, III: 19, IV: 10; serous adenocarcinoma: 21, endometrioid adenocarcinoma: 5, undifferentiated: 7) were included in this array study. All cases received staging laparotomy, cytoreductive surgery, and adjuvant chemotherapy (carboplatin + paclitaxel) as primary therapy. Results: Class comparison analysis between groups of NED (no evidence of disease) and non-NED identified 46 genes that exhibited significant differences (p < 0.001). Among them, 6 (13%) genes are located in 8q24 and 9 (19.6%) genes are located in 20q11–13. Finally, we focused on 8q24 and 20q11–13 loci, and confirmed array data using real-time quantitative PCR in 94 validation sets. The validation showed that ZNF7, MAF1, ADRM1, and GNAS amplification was related with PFS (p < 0.05, respectively). Conclusions: The amplification of 8q24 and 20q11–13 can predict the PFS of aEOC and these genes may be new biomarkers for aEOC.

No significant financial relationships to disclose.

Effects of weekly bevacizumab and pegylated liposomal doxorubicin in heavily pretreated patients with recurrent or progressed ovarian cancer

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Background: Vascular endothelial growth factor (VEGF) plays a central role in tumor angiogenesis and is regarded a promising therapeutic target. Bevacizumab (A) has significant antitumor activity in combination with cytotoxic agents. Currently, pegylated liposomal doxorubicin (D) is provided as one of the standard treatment options in recurrent ovarian cancer. Thus, we attempted to determine effects in combination of A and D for heavily pretreated patients with recurrent or progressed ovarian cancer. Methods: Twenty-two patients with heavily pretreated (more than one regimen or more than 6 cycles by paclitaxerl and carboplatin) received at least more than 3 cycles of weekly A-D consisting of A: 2 mg/kg and D: 10 mg/m2 (3 weeks, one week rest). The primary endpoint was response according to CA 125 and response evaluation criteria in solid tumor (RECIST) criteria. Results: Of 22 patients evaluable for CA 125 response, 7 (32%) had a response (decrease of >50%), and 8 (36%) patients had not progressed (doubling of CA 125) following 6 months on treatment. In RECIST evaluation, 2 (9%) patients had complete remission (CR) and 6 (27%) had partial remission (PR), resulting in 55% clinical benefit rate (CBR). Progression free interval (PFI) showed more than 6 months. Any hematological adverse effect was not observed in the present study. Gastrointestinal perforation was observed in only one case and was conservatively treated. Although nasal bleeding was frequently observed, no treatment was required. A induced hypertension was also observed and manageable. Hand-foot syndrome seemed due to D was seen in 3 of 22 patients and treatment was required in only one case. Conclusions: B seemed to enhance effect of D. This is the first study of weekly A-D in heavily pretreated ovarian cancer patients. Weekly A-D warrants further clinical study in such clinical settings.

No significant financial relationships to disclose.

Unconventional superconductivity of NpPd(5)Al(2)

The high quality single crystals of NpPd(5)Al(2) with the body-centered tetragonal structure were grown by the Pb flux method. NpPd(5)Al(2) was found to be the first Np-based heavy fermion superconductor with the relatively high critical temperature T(sc) = 4.9 K. The upper critical field H(c2) is large and highly anisotropic. Corresponding to the heavy electronic state, the initial slope of H(c2) is large, but H(c2) at low temperatures is suppressed by the magnetic field, indicating a strong Pauli paramagnetic effect and the first-order transition at H(c2). These results imply that NpPd(5)Al(2) is located at the proximity of the antiferromagnetic ordering, which might be hidden by the superconductivity. The d-wave superconductivity with a spin singlet state is most likely realized in NpPd(5)Al(2).

[Clinical study of carcinoma of the penis]

We retrospectively analyzed the records of 21 patients with penile carcinoma treated between January 1993 and February 2007. According to TMN classification (UICC 2002), 9, 8, 2 and 2 patients belonged to stages I, II, III and IV, respectively. During the follow up period of 4 to 144 months (median 15 months), the overall 5-year survival rate was 75.8%. All three patients having N2 died within one year. Lymph node metastasis (p = 0.001) and organ metastasis (p = 0.007) were found to be unfavorable prognostic factors for patients with penile cancer.

Can ABCF2 protein expression predict the prognosis of uterine cancer?

Uterine cervical and endometrial cancers are common malignant solid neoplasms for which there are no useful prognostic markers. In this study, we evaluate the relationship between ATP-binding cassette superfamily F2 (ABCF2) expression and clinical factors including clinical stage, histologic type, grade and prognosis in uterine cervical and endometrial cancer. Two hundred and sixty seven cervical and 103 endometrial cancers were studied. ATP-binding cassette superfamily F2 cytoplasmic expression was detected by immunohistochemical staining and scored as positive or negative. Among cervical cancer cases, 149 (55.8%) expressed ABCF2. The overall survival was longer in ABCF2-negative than ABCF2-positive cases (P=0.0069). Statistically significant prognostic factors for survival were ABCF2 positivity (risk ratio (rr)=1.437), old age (rr=1.550) and advanced stage (rr=2.577). ATP-binding cassette superfamily F2 positivity was an independent prognostic factor by multivariate proportional hazard test (P=0.0002). Among endometrial cancer cases, 72 (69.9%) were cytoplasmic ABCF2 positive. However, there was no significant relationship between ABCF2 expression and age, clinical stage, histologic type, histologic grade, oestrogen receptor status or prognosis. ATP-binding cassette superfamily F2 expression may be a useful prognostic marker in cervical but not endometrial cancer. The role of ABCF2 protein may differ depending on the type of cancer.

Multigap superconductivity in the heavy-Fermion system CeCoIn5

New thermal conductivity experiments on the heavy-fermion superconductor CeCoIn5 down to 10 mK rule out the suggested existence of unpaired electrons. Moreover, they reveal strong multigap effects with a remarkably low "critical" field Hc2S for the small gap band, showing that the complexity of heavy-fermion band structure has a direct impact on their response under magnetic field.

Human monoclonal antibody for ovarian clear cell carcinoma-2, a human monoclonal antibody with antitumor activity against ovarian cancer cells that recognizes CA125-like antigen

In recent years, antibody therapy employing monoclonal antibodies has become a new approach for treating cancer. This study was performed to establish a human monoclonal antibody recognizing an epitope related to CA125 using KM mice and to assess its reactivity with ovarian cancer cells. A human ovarian clear cell adenocarcinoma cell line (RMG-I) was used to immunize KM mice, and hybridoma supernatant was obtained by a standard method employing enzyme-linked immunosorbent assay screening. Next, selection of hybridomas was performed with two antibodies (MA602-1 and MA602-6) and a sandwich immunoassay for CA125-like antigen, and then the limiting dilution was used to obtain a human monoclonal antibody. Immunohistochemical reactivity of this antibody (human monoclonal antibody for ovarian clear cell carcinoma-2 [HMOCC-2]) with ovarian cancer was assessed, while its specificity was analyzed by Western blotting. Various antibodies were used to identify the epitope targeted by HMOCC-2. Finally, the antitumor effect of HMOCC-2 was assessed by intraperitoneal administration to SCID (severe combined immunodeficiency) mice with heterografts of RMG-I tumors. HMOCC-2 showed a positive reaction with 60% (63/105) of ovarian cancer specimens. Western blotting of the membrane fraction of RMG-I revealed several bands at 120-250 kd. HMOCC-2 recognized the CA125-like antigens identified by several antibodies. HMOCC-2 also exhibited significant antitumor activity (P < 0.01) against ovarian cancer heterografts. HMOCC-2 reacts specifically with ovarian cancer cells via a target epitope analogous to that of CA125 and also exhibits activity against ovarian tumors. These findings suggest that it may have the potential to be employed clinically for molecular-targeting therapy.

Magnetic structure of CeRhIn(5) under magnetic field

The magnetically ordered ground state of CeRhIn(5) at ambient pressure and zero magnetic field is an incommensurate helicoidal phase with the propagation vector k = (1/2,1/2,0.298) and the magnetic moment in the basal plane of the tetragonal structure. We determined by neutron diffraction the two different magnetically ordered phases of CeRhIn(5) evidenced by bulk measurements under applied magnetic field in the basal plane. The low temperature high magnetic phase corresponds to a commensurate sine-wave structure of the magnetization with k = (1/2,1/2,1/4). At high temperature, the phase is incommensurate with k = (1/2,1/2,0.298) and a possible small ellipticity. The propagation vector of this phase is the same as that of the zero-field structure.

Cyclin-dependent kinase (CDK) activity as a prognostic marker in primary epithelial ovarian cancer

5575

Background: The unpredictable nature of primary epithelial ovarian cancer (EOC) response to treatment necessitates the identification of factors that predict long-term outcome. CDK activity is the core regulator of the cell-cycle checkpoint for cancer cells. We previously found that cell death induced by taxanes requires increased activity of CDK1 and CDK2- fundamental kinases in cell proliferation. Thus, we hypothesized that CDK1/2 activities can determine the prognosis of patients with primary EOC. Methods: We retrospectively analyzed frozen ovarian cancer specimens from 72 women treated with cytoreductive surgery and adjuvant chemotherapy for newly diagnosed EOC. Median patient age was 61 years (range, 38–80), 91% had FIGO stage III/IV disease, and 86% were treated with platinum- or taxane-based regimens. Median follow-up was 32 months; median time to treatment failure (TTF), defined as time from surgery to first relapse for patients who had achieved complete response or time to disease progression for those who had persistent disease, was 15 months. Enzymatic activity of CDK1/2 in the tumor tissues was determined by a modified in vitro kinase activity assay using a C2P device (Sysmex Inc.). Recursive partitioning and regression trees algorithm (RPART) was used to identify the cohorts based on CDK1/2 activities. Results: In the univariate analysis, disease stage (p=0.021), type of surgery (optimal vs. suboptimal) (p=0.004), presence of ascites (p=0.043), and CA125 after the adjuvant therapy (p=0.005) were significant predictors of TTF. The cohort with CDK2 activity = 87.3 had a significantly shorter TTF (p=0.014) and the cohort with CDK1 activity = 226.35 showed a trend toward longer TTF (p=0.094). Multivariate Cox proportional hazards regression analysis revealed CDK2 activity (<87.3 vs. = 87.3) (p=0.012) and CA125 level at completion of the adjuvant chemotherapy regimen (p=0.02) to be independent predictors of TTF. Conclusion: Our data supports kinase activity of cell cycle as a clinically significant prognostic factor. To extend these findings, we plan to conduct a large prospective study to determine whether CDK1/2 profiling can predict long-term outcome in primary EOC.

[Table: see text]

NMR evidence for higher-order multipole order parameters in NpO2

We report a microscopic investigation of multipolar order parameters in the ordered state of NpO2 conducted via 17O NMR on a single crystal. From the angular dependence of hyperfine fields at 17O nuclei, we have obtained clear evidence for the appearance of field-induced antiferro-octupolar as well as field-induced antiferro-dipolar moments below T0 = 26 K. We have also observed oscillatory spin-echo decay, which is well understood in terms of small electric field gradients created by antiferro-quadrupolar ordering. This reveals that the quadrupolar order parameter is directly observable by means of NMR. The present NMR studies provide definitive support for a proposed longitudinal triple-q type octupolar-quadrupolar ordering model for NpO2.

Analysis of clinicopathologic factors predicting para-aortic lymph node metastasis in endometrial cancer

The purposes of this study were to compare the relationships between para-aortic lymph node metastasis and various clinicopathologic factors to evaluate whether para-aortic lymph node dissection is necessary when treating endometrial cancer. A retrospective study was performed on 841 patients with endometrial cancer, who underwent the initial surgery at the Keio University Hospital. Clinicopathologic factors related to para-aortic lymph node metastasis significant on a univariate analysis were analyzed in a multivariate fashion using a logistic model. According to the multivariate analysis, the clinicopathologic factor most strongly related to the existence of para-aortic lymph node metastasis was positive pelvic lymph node metastasis (P < 0.01). Among the 155 patients who underwent pelvic and para-aortic lymph node dissection, the difference of 5-year overall survival by the presence of retroperitoneal lymph node metastasis was examined by Kaplan-Meier method. The prognosis was poor even if para-aortic lymph node dissection was performed in cases of positive para-aortic lymph node metastasis. In conclusion, when deciding whether to perform para-aortic lymph node dissection in patients with endometrial cancer, it is necessary to consider the pelvic lymph nodal status. If there is no pelvic lymph node metastasis, it could not be necessary to perform para-aortic lymph node dissection.