Synthesis, Structure, and Cytotoxicity of Oxaliplatin-Based Platinum(IV) Anticancer Prodrugs Bearing One Axial Fluoride

Fluorine plays more and more important roles in drug design and development. In recent years, fluorine-containing organic drugs have already been applied in a broad range of therapeutic areas. Herein, we report our attempt to introduce an axial fluorine ligand to Pt(IV) complexes by oxidizing oxaliplatin with electrophilic fluorinating reagents in different protic solvents. The crystal structure of one representative complex is presented. The fluorinated Pt(IV) complexes are further expanded by functionalization with different anhydrides, and their analogues bearing one different axial ligand (OAc or OH group) are also synthesized. Further investigations show that the axial fluorine atom has dramatic effects on the chemical properties of these prodrugs. These new fluorinated Pt(IV) complexes are proved to be stable in physiological conditions. For most of the fluorinated Pt(IV) complexes, a higher reduction potential indicates its greater tendency to be reduced by ascorbate. Introducing an axial fluorine ligand in Pt(IV) complexes does not lead to the increase of their lipophilicity. Moreover, these new fluorinated Pt(IV) complexes show better cytotoxicity than nonfluorinated analogues which may derive from their higher cellular accumulation in cancer cells. Therefore, the good stability and high cytotoxicity of these fluorinated Pt(IV) prodrugs indicate their great potential as a building block for further functionalization.

Overexpression of EPS8L3 promotes cell proliferation by inhibiting the transactivity of FOXO1 in HCC

The homology of epidermal growth factor receptor pathway substrate 8 (EPS8), EPS8L3, is elevated significantly in hepatocellular carcinoma (HCC) tissues and cell lines compared with the normal liver tissues and cell lines. The MTT and colony formation assays demonstrated that overexpressing EPS8L3 enhances, while silencing reduces the proliferation of HCC cells. Further experiments illustrated that overexpressing EPS8L3 promotes the expression of p-AKT, Cyclin D1, but inhibits the transcriptional activity of FOXO1. Besides, colony formation assay demonstrated that AKT inhibitor suppresses the effect of EPS8L3 on proliferation in EPS8L3-overexpressing cells, whereas AKT restores the proliferation of EPS8L3-silenced cells, suggesting that EPS8L3 might promote proliferation by hyperactivating the AKT signaling pathway and subsequently inhibiting the FOXO1 transcriptional activity. Our results provide new view between EPS8L3 and progression of human HCC, suggesting that EPS8L3 may be a novel therapeutic target for HCC.

Abstract PD3-08: A randomized phase II trial of pyrotinib plus capecitabine versus lapatinib plus capecitabine in patients with HER2-positive metastatic breast cancer previously treated with taxanes, anthracyclines and/or trastuzumab

Background:Pyrotinib is an oral, irreversible pan-ErbB receptor tyrosine kinase inhibitor (TKI) with activity against epidermal growth factor receptor (EGFR) / HER1, HER2, and HER4. Lapatinib in combination with capecitabine is one of the standards of care for patients with HER2-positive metastatic breast cancer (MBC) who have received prior taxanes, anthracyclines and/or trastuzumab.

Methods: We conducted an open label, multicenter, randomized phase II trial to comparatively evaluate efficacy and safety of pyrotinib + capecitabine (PC) or lapatinib + capecitabine (LC) in women with HER2-positive MBC. Key eligibility criteria included prior treatment with taxanes, anthracyclines and/or trastuzumab, ≤2 prior chemotherapies for metastatic disease, no CNS metastases, and no prior treatment with HER2 targeted TKI. Eligible patients were randomized 1:1 to PC Arm (P 400 mg QD D1–21 + C 1000 mg/m2BID D1–14, 21-D cycle) or LC Arm (L 1250 mg QD D1–21 + C 1000 mg/m2BID D1–14, 21-D cycle). The primary endpoint was objective response rate (ORR) as assessed by investigator, and secondary endpoints included progression-free survival (PFS), time to progression (TTP), duration of response (DoR), overall survival (OS), and safety.

Results: Between May 2015 and Mar 2016, 128 patients (65 in PC arm and 63 in LC arm) were enrolled in this study. Median age was 48 years (range 25-70), ECOG performance status was 0 (53.9%) or 1 (46.1%), 62.5% had hormone receptor-positive disease, 76.6% had visceral disease and 53.9% had received prior trastuzumab in (neo)adjuvant and/or mestastatic setting. Baseline characteristics were well balanced in two arms. Median follow-up time was 15.0 months. ORR was 78.5% in PC arm and 57.1% in LC arm (p=0.01), Median PFS was 18.1 months in PC arm and 7.0 months in LC arm (hazard ratio 0.363; 95% CI 0.228, 0.579; p<0.0001), PFS benefit in PC arm compared to LC arm was observed irrespective of prior trastuzumab or not. Treatment related Grade 3-4 toxicities occurred in >2% patients in PC arm vs LC arm included hand-foot syndrome (21.5% vs 19.0%), diarrhea (13.8% vs 4.8%), decreased neutrophil (7.7% vs 1.6%), decreased WBC (6.2% vs 1.6%), vomiting (4.6% vs 0%), increased AST (3.1% vs 1.6%), decreased hemoglobin (3.1% vs 1.6%), increased total bilirubin (0% vs 4.8%) and increased conjugated bilirubin (0% vs 3.2%).

Conclusions: In women with HER2-positive MBC previously treated with taxanes, anthracyclines and/or trastuzumab, pyrotinib + capecitabine yield statistically significant better PFS and ORR than lapatinib + capecitabine in this randomized phase II trial. Phase III study is ongoing to validate this finding.

Citation Format: Xu B, Ma F, Ouyang Q, Li W, Jiang Z, Tong Z, Liu Y, Li H, Yu S, Feng J, Wang S, Hu X, Zhu X, Zou J. A randomized phase II trial of pyrotinib plus capecitabine versus lapatinib plus capecitabine in patients with HER2-positive metastatic breast cancer previously treated with taxanes, anthracyclines and/or trastuzumab [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-08.

Irradiation after surgery for breast cancer patients with primary tumours and one to three positive axillary lymph nodes: yes or no?

OBJECTIVE AND METHODS

We retrospectively analyzed clinicopathologic features and survival in breast cancer patients who had T1 or T2 primary tumours and 1-3 histologically involved axillary lymph nodes and who were treated with modified radical mastectomy without adjuvant radiotherapy (rt). We also explored prognosis to find the high- and low-risk groups.

RESULTS

From May 2001 to April 2005, 368 patients treated at Tianjin Tumor Hospital met the study criteria. The 5- and 8-year rates were 7.2% and 10.7% for locoregional recurrence (lrr), 85.1% and 77.7% for disease-free survival (dfs), and 92.8% and 89.3% for overall survival (os). Multivariate Cox regression analysis showed that age, tumour size, estrogen receptor (er) status, and lymphovascular invasion (lvi) were independent prognostic factors for lrr and dfs. Based on 4 patient-related factors that indicate poor prognosis (age < 40 years, tumour > 3 cm, er negativity, and lvi), the high-risk group (patients with 3 or 4 factors, accounting for 12.5% of the cohort) had 5- and 8-year rates of 24.3% and 36.9% for lrr, 57.2% and 39.2% for dfs, and 74.8% and 43.8% for os compared with 5.0% and 7.1% for lrr, 88.9% and 83.1% for dfs, 91.6% and 83.4% for os in the low-risk group (patients with 0-2 factors, accounting for 87.5% of the cohort; p < 0.001).

CONCLUSIONS

Our study identified several risk factors that correlated independently with a greater incidence of lrr and distant metastasis in patients with T1 and T2 breast cancer and 1-3 positive nodes. Patients with 0-2 risk factors may not be likely to benefit from post-mastectomy rt, but patients with 3-4 risk factors may need rt to optimize locoregional control and improve survival.

Succinate is an inflammatory signal that induces IL-1β through HIF-1α

Macrophages activated by the Gram-negative bacterial product lipopolysaccharide switch their core metabolism from oxidative phosphorylation to glycolysis. Here we show that inhibition of glycolysis with 2-deoxyglucose suppresses lipopolysaccharide-induced interleukin-1β but not tumour-necrosis factor-α in mouse macrophages. A comprehensive metabolic map of lipopolysaccharide-activated macrophages shows upregulation of glycolytic and downregulation of mitochondrial genes, which correlates directly with the expression profiles of altered metabolites. Lipopolysaccharide strongly increases the levels of the tricarboxylic-acid cycle intermediate succinate. Glutamine-dependent anerplerosis is the principal source of succinate, although the 'GABA (γ-aminobutyric acid) shunt' pathway also has a role. Lipopolysaccharide-induced succinate stabilizes hypoxia-inducible factor-1α, an effect that is inhibited by 2-deoxyglucose, with interleukin-1β as an important target. Lipopolysaccharide also increases succinylation of several proteins. We therefore identify succinate as a metabolite in innate immune signalling, which enhances interleukin-1β production during inflammation.

Injection of air into the headspace improves fermentation of phosphoric acid pretreated sugarcane bagasse by Escherichia coli MM170

Microaeration (injecting air into the headspace) improved the fermentation of hemicellulose hydrolysates obtained from the phosphoric acid pretreatment of sugarcane bagasse at 170°C for 10 min. In addition, with 10% slurries of phosphoric acid pretreated bagasse (180°C, 10 min), air injection into the headspace promoted xylose utilization and increased ethanol yields from 0.16 to 0.20 g ethanol/g bagasse dry weight using a liquefaction plus simultaneous saccharification and co-fermentation process (L+SScF). This process was scaled up to 80 L using slurries of acid pretreated bagasse (96 h incubation; 0.6L of air/min into the headspace) with ethanol yields of 312-347 L (82-92 gal) per tone (dry matter), corresponding to 0.25 and 0.27 g/g bagasse (dry weight). Injection of small amounts of air into the headspace may provide a convenient alternative to subsurface sparging that avoids problems of foaming, sparger hygiene, flotation of particulates, and phase separation.

Higher-capacity communication links based on two-mode phase-sensitive amplifiers

Optical communication links are usually made with erbium-doped fiber amplifiers, which amplify the signal waves in a phase-insensitive (PI) manner. They can also be made with parametric fiber amplifiers, in which the signal waves interact with idler waves. If information is transmitted using only the signals, parametric amplifiers are PI and their noise figures are comparable to those of erbium amplifiers. However, transmitting correlated information in the signals and idlers, or copying the signals prior to transmission, allows parametric amplifiers to be phase-sensitive (PS), which lowers their noise figures. The information capacities of two-mode PS links exceed those of the corresponding PI links by 2 b/s-Hz.

Effect of reduced sulfur compounds on the fermentation of phosphoric acid pretreated sugarcane bagasse by ethanologenic Escherichia coli

The addition of reduced sulfur compounds (thiosulfate, cysteine, sodium hydrosulfite, and sodium metabisulfite) increased growth and fermentation of dilute acid hydrolysate of sugarcane bagasse by ethanologenic Escherichia coli (strains LY180, EMFR9, and MM160). With sodium metabisulfite (0.5mM), toxicity was sufficiently reduced that slurries of pretreated biomass (10% dry weight including fiber and solubles) could be fermented by E. coli strain MM160 without solid-liquid separation or cleanup of sugars. A 6-h liquefaction step was added to improve mixing. Sodium metabisulfite also caused spectral changes at wavelengths corresponding to furfural and soluble products from lignin. Glucose and cellobiose were rapidly metabolized. Xylose utilization was improved by sodium metabisulfite but remained incomplete after 144 h. The overall ethanol yield for this liquefaction plus simultaneous saccharification and co-fermentation process was 0.20 g ethanol/g bagasse dry weight, 250 L/tonne (61 gal/US ton).

Noise performance of a frequency nondegenerate phase-sensitive amplifier with unequalized inputs

For the first time to our knowledge, the noise performance of a frequency nondegenerate phase-sensitive amplifier (PSA) with unequalized input powers has been experimentally characterized, based on a fiber-based parametric copier-PSA scheme. Two different noise-figure (NF) definitions-separate and combined NFs-are provided and compared. The results show that the separate NF of the weaker input wave is lower than that of the stronger wave due to the correlated-light nature. When considering the combined NF, the optimal noise performance (0 dB NF) is obtained only when the input powers are equal. Experiments agree well with the theoretical predictions.

Field-quadrature and photon-number correlations produced by parametric processes

In a previous paper [Opt. Express 13, 4986 (2005)], formulas were derived for the field-quadrature and photon-number variances produced by multiple-mode parametric processes. In this paper, formulas are derived for the quadrature and number correlations. The number formulas are used to analyze the properties of basic devices, such as two-mode amplifiers, attenuators and frequency convertors, and composite systems made from these devices, such as cascaded parametric amplifiers and communication links. Amplifiers generate idlers that are correlated with the amplified signals, or correlate pre-existing pairs of modes, whereas attenuators decorrelate pre-existing modes. Both types of device modify the signal-to-noise ratios (SNRs) of the modes on which they act. Amplifiers decrease or increase the mode SNRs, depending on whether they are operated in phase-insensitive (PI) or phase-sensitive (PS) manners, respectively, whereas attenuators always decrease these SNRs. Two-mode PS links are sequences of transmission fibers (attenuators) followed by two-mode PS amplifiers. Not only do these PS links have noise figures that are 6-dB lower than those of the corresponding PI links, they also produce idlers that are (almost) completely correlated with the signals. By detecting the signals and idlers, one can eliminate the effects of electronic noise in the detectors.

A Selective Medium for the Isolation and Quantification of Bradyrhizobium japonicum and Bradyrhizobium elkanii Strains from Soils and Inoculants

The ecological examination of members of the family Rhizobiaceae has been hampered by the lack of a selective medium for isolation of root nodule bacteria from soil. A novel non-antibiotic-containing medium has been developed which allows selective isolation of Bradyrhizobium japonicum and B. elkanii strains from soil and inoculants. The medium, BJSM, is based on the resistance of B.japonicum and B. elkanii strains to more than 40 mug of the metals ions Zn and Co per ml. BJSM does not allow growth of Rhizobium sp. strains. We used BJSM to isolate bacteria from a Hubbard soil and from several commercially prepared soybean inoculants. Ninety-eight percent of the isolates obtained from Hubbard soil nodulated Glycine max cv. Kasota, and between 55 and 95% of the isolates from the commercial inoculants had the ability to nodulate soybeans. Numbers of bradyrhizobia obtained by using BJSM, strain-specific fluorescent antibodies, and the most-probable-number plant infection assay indicated that the three techniques were comparable in quantifying B. japonicum strains in soils and inoculants, although most-probable-number counts were generally 0.5 order of magnitude greater than those obtained by using BJSM. Results of our studies indicate that BJSM is useful for direct isolation and quantification of B. japonicum and B. elkanii from natural soils and inoculants. This medium may prove to be an important tool for autecological and enumeration studies of diverse populations of bradyrhizobia and as a quality control method for soybean inoculants.