Labeling strategy and signal broadening mechanism of Protein NMR spectroscopy in Xenopus laevis oocytes

We used Xenopus laevis oocytes, a paradigm for a variety of biological studies, as a eukaryotic model system for in-cell protein NMR spectroscopy. The small globular protein GB1 was one of the first studied in Xenopus oocytes, but there have been few reports since then of high-resolution spectra in oocytes. The scarcity of data is at least partly due to the lack of good labeling strategies and the paucity of information on resonance broadening mechanisms. Here, we systematically evaluate isotope enrichment and labeling methods in oocytes injected with five different proteins with molecular masses of 6 to 54 kDa. (19) F labeling is more promising than (15) N, (13) C, and (2) H enrichment. We also used (19) F NMR spectroscopy to quantify the contribution of viscosity, weak interactions, and sample inhomogeneity to resonance broadening in cells. We found that the viscosity in oocytes is only about 1.2 times that of water, and that inhomogeneous broadening is a major factor in determining line width in these cells.

Resistin as a potential marker of renal disease in lupus nephritis

Systemic lupus erythematosus (SLE) and lupus nephritis (LN) have strong concomitance with cardiovascular disease that cannot be explained fully by typical risk factors. We examined the possibility that serum or urine expression of adipokines may act as biomarkers for LN, as these proteins have been associated previously with cardiovascular disease as well as SLE. Antibody arrays were performed on serum and urine from lupus patients and matched controls using a cross-sectional study design. From the initial array-based screening data of 15 adipokines, adiponectin, leptin and resistin were selected for validation by enzyme-linked immunosorbent assay (ELISA). Correlations were determined between adipokine expression levels and measures of disease activity or lupus nephritis. The expression of adiponectin and resistin was increased in both sera and urine from LN patients, while leptin was increased in LN patient sera, compared to matched controls. Serum resistin, but not urine resistin, was correlated with measures of renal dysfunction in LN. Serum resistin expression may be useful as a marker of renal dysfunction in patients with LN, although longitudinal studies are warranted. Further studies are necessary to determine if resistin has functional consequences in LN.

Prospective controlled study of the safety and oncological outcomes of ELAPE procure with definitive anatomic landmarks versus conventional APE for lower rectal cancer

BACKGROUND

The use of extra-levator abdominoperineal resection (ELAPE) procedure for lower rectal cancer is controversial. It is unclear whether the ELAPE procedure could improve surgical safety and lead to better oncological outcomes.

METHODS

Sixty-nine lower rectal cancer patients who underwent ELAPE (36 cases) or conventional abdominoperineal resection (APE; 33 cases) between June 2011 and February 2013 were prospectively investigated. Clinicopathological variables including blood loss, intraoperative perforation (IOP) rate, circumferential resection margin (CRM) involvement, lymph node harvest, the postoperative complications, urinary and sexual function, quality of life (QOL), local recurrence rate and survival were recorded and compared.

RESULTS

Blood loss (P = 0.021), perineal wound complication (P = 0.039), IOP rate (P = 0.028), local recurrence (P = 0.034) were significantly less frequent in the ELAPE group. There was greater CRM involvement in the conventional APE group but no statistical difference between the two groups. Urinary function, sexual function and QOL were not significantly different between the two groups. Overall survival and progression-free survival were not significantly different between two groups, even when survival was analyzed according to TNM stage, T stage, N stage, and with or without neoadjuvant chemoradiotherapy. In patients who underwent ELAPE there was no statistical difference in postoperative complications between younger and elderly patients (age ≥60).

CONCLUSIONS

ELAPE procedure with definitive anatomic landmarks demonstrated surgical safety and decreased local recurrence for lower rectal cancer patients including the elderly, but there were no survival improvements in compared to conventional APE procedure.

Extracellular matrix metalloproteinase inducer (EMMPRIN) remodels the extracellular matrix through enhancing matrix metalloproteinases (MMPs) and inhibiting tissue inhibitors of MMPs expression in HPV-positive cervical cancer cells

PUPOSE OF INVESTIGATION: To study the expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), and tissue inhibitors of MMP (TIMPs) in uterine cervical cancer cell lines in vitro.

MATERIALS AND METHODS

EMMPRIN, MMPs, and TIMPs expression were assessed by Western blot and real-time RT-PCR from cervical carcinoma SiHa, HeLa, and C33-A cells.

RESULTS

EMMPRIN recombinant significantly increased MMP-2, MMP-9 protein and mRNA expression in SiHa and Hela cells, but not in C33-A cells by Western blot analysis and real-time RT-PCR. EMMPRIN recombinant significantly inhibited TIMP-1 protein and mRNA levels in SiHa and Hela cells, but not in C33-A cells. There was no difference on the TIMP-2 expression in those cells with the treatment of EMMPRIN recombinant. EMMPRIN RNAi decreased MMP-2 and MMP-9 and increased TIMP-1 expression in SiHa and HeLa cells, but not in C33-A cells. There was no change on the expression of TIMP-2 mRNA levels in SiHa, HeLa and C33-A cells transfected with siEMMPRIN.

CONCLUSION

EMMPRIN may induce MMP-2 and MMP-9, and downregulate TIMP-1 in HPV-positive cervical cancer cells in vitro.

Exploring the significance of sex hormone-binding globulin examination in the treament of women with polycystic ovarian syndrome (PCOS)

OBJECTIVES

To explore whether sex hormone-binding globulin (SHBG) and free androgen index (FAI) can be seen as therapeutic effect indexes of women with polycystic ovarian syndrome (PCOS).

MATERIALS AND METHODS

The body mass index (BMI), basal sexual hormones, SHBG, fasting blood glucose (FBG), and fasting insulin (FINS) were collected from 579 women with PCOS, were divided into two groups according to BMI: obese group (n = 145) and non-obese group (n = 434), according to homeostasis model assessment of insulin status (HOMA-IR). Patients were then divided into four groups: A: non-obese without insulin resistance (n = 174), B: non-obese with insulin resistance (n = 260), C: obese without insulin resistance (n = 34), D: obese with insulin resistance (n = 111). A and B groups received Diane-35 alone, C and D groups received Diane-35 plus metformin for three months. Then clomiphene citrate and HMAG were used to induce ovulation then compared ovulation rate and pregnancy outcome.

RESULTS

FAI decreased significantly and SHBG increased significantly in all groups. In A group FINS and HOMA-IR increased significantly (p < 0.05), but in B and D groups FINS and HOMA-IR decreased significantly (p < 0.05). After treatment the ovulation rate in non-obese group was higher than obese group (p < 0.01). Compared with non-ovulation patients, SHBG increased significantly and FAI decreased significantly in the patient with ovulation. Regarding the pregnancy outcome, FAI decreased significantly in delivery patients than spontaneous abortion patients. Furthermore, SHBG increased significantly.

CONCLUSION

It was important to check SHBG and FAI during the treatment of PCOS patient. They could be used to assess whether the treatment was effective and as a guidance of clinical medication.

Testing the mutant selection window hypothesis in vitro and in vivo with Staphylococcus aureus exposed to fosfomycin

The purpose of this study was to test the mutant selection window (MSW) hypothesis in vitro and in vivo with Staphylococcus aureus exposed to fosfomycin. With the in vitro time-kill studies, S. aureus ATCC 29213 [with a minimal concentration that inhibits colony formation by 99% (MIC99) of 2.2 μg/mL and a mutant prevention concentration (MPC) of 57.6 μg/mL] lost fosfomycin susceptibility at antibiotic concentrations (2×, 4×, and 8× MIC) that are between the lower and upper boundaries of the MSW. In the tissue-cage model, S. aureus was exposed to fosfomycin pharmacokinetics at concentrations below the MIC99, between the MIC99 and the MPC, and above the MPC, respectively. Changes in susceptibility and counts of total and resistant viable bacteria were monitored in tissue-cage fluid obtained daily. However, the selection of resistant mutants was not observed during antibacterial treatment and 48 h after the termination of fosfomycin treatment, regardless of the fosfomycin dosage. Besides, we found no differences between the in vitro-isolated mutant and its sensitive parental strain, which indicates the absence of fitness cost of fosfomycin resistance in S. aureus ATCC 29213. These findings demonstrate that agar plate determinations do not fit the MSW for fosfomycin treatment of rabbits infected with S. aureus ATCC 29213; therefore, the existence of the window must be demonstrated not only in vitro but also in vivo. Further research is needed on the exact mechanism of resistance.

Adipocytes contribute to resistance of human melanoma cells to chemotherapy and targeted therapy

Epidemiological evidence has linked the development and progression of several cancers including melanoma with obesity. However, whether obesity impinges on responses of cancer cells to treatment remains less understood. Here we report that human adipocytes contribute to resistance of melanoma cells to various therapeutic agents. Exposure to media from adipocyte cultures (adipocyte media) increased cell proliferation and reduced sensitivity of melanoma cells to apoptosis induced by diverse chemotherapeutic drugs, including the DNA-damaging drug cisplatin, the microtubuletargeting agent docetaxel, and the histone deacetylase inhibitor SAHA. This was associated with increased activation of PI3K/Akt and MEK/ERK signaling, and was attenuated by a PI3K or MEK inhibitor. The effect of adipocyte media on melanoma cells was, at least in part, due to the interaction between the adipokine leptin and its long form receptor OB-Rb, in that immunodepletion of leptin in adipocyte media or siRNA knockdown of OB-Rb in melanoma cells reversed the increase in Akt and ERK activation, enhancement in cell proliferation, and importantly, protection of melanoma cells against the drugs. In support, recombinant leptin partially recapitulated the effect of adipocyte media on melanoma cells. Of note, OB-Rb was increased on the surface of melanoma cells compared to melanocytes, whereas leptin short form receptors appeared to be suppressed post-transcriptionally, suggesting that OB-Rb was selectively upregulated in melanoma cells. Collectively, these results indicate that adipocytes contribute to the resistance of melanoma cells to chemotherapeutic drugs and agents targeting the PI3K/Akt and MEK/ERK pathways, and suggest that inhibition of the leptin/ OB-Rb system may be useful to improve the efficacy of multiple therapeutic approaches in the treatment of melanoma.

The prognostic significance of left ventricular ejection fraction in patients with advanced cancer treated in phase I clinical trials

BACKGROUND

New targeted agents may cause acute cardiac events. The purpose of our study was to investigate the incidence and the prognostic significance of left ventricular ejection fraction (LVEF) in phase I trials.

PATIENTS AND METHODS

Between October 2008 and September 2011, the records of 1166 consecutive patients with advanced cancer treated in the Phase I Clinic who underwent echocardiography were retrospectively reviewed.

RESULTS

Most of the patients were White (78%), and the most common tumor types were colorectal cancer and melanoma. Of 1166 patients, 177 (15.2%) patients had an LVEF of <50%. No difference in overall survival (OS) between patients with LVEF ≥ 50% and patients with LVEF < 50% was seen (median OS 7.4 versus 7.0 months, P = 0.84). Patients with LVEF ≤ 35% had shorter survival compared with those with LVEF between 35% and 50% (median 4.2 versus 8.0 months; P = 0.005). In multivariate analysis of patients with LVEF < 50%, independent factors predicting longer survival were LVEF > 35%, ≤2 prior systemic therapies, ≤2 metastatic sites, and normal lactate dehydrogenase and albumin levels.

CONCLUSION

Echocardiography would improve patient selection for enrollment in phase I clinical trials. These data suggest that it is safe to treat patients with LVEF between 35% and 50%.

Small-volume vitrification for human spermatozoa in the absence of cryoprotectants by using Cryotop

Cryotop is a carrier that has been used successfully in the cryopreservation of human spermatozoa. Here, we explored a novel method to vitrify human spermatozoa without cryoprotective agents (CPAs) using Cryotop. Spermatozoa from 21 Normozoospermic patients were collected and vitrified without CPAs or with sucrose in small volume using Cryotop. The sperm recovery rate, motility, viability, chromatin damage and DNA fragmentation were assessed. No significant difference was observed in the sperm recovery rate and motility rate between the spermatozoa cryopreserved without CPAs and with sucrose. The post-thawed spermatozoa cryopreserved without CPAs had a higher viability and lower damage to sperm chromatin and DNA than those cryopreserved with sucrose. These results suggest that small numbers of human spermatozoa can be successfully vitrified without CPAs using Cryotop.

Inflammation-related genetic variants predict toxicity following definitive radiotherapy for lung cancer

Definitive radiotherapy improves locoregional control and survival in inoperable non-small cell lung cancer (NSCLC) patients. However, radiation-induced toxicities (pneumonitis/esophagitis) are common dose-limiting inflammatory conditions. We therefore conducted a pathway-based analysis to identify inflammation-related SNPs associated with radiation-induced pneumonitis or esophagitis. 11,930 SNPs were genotyped in 201 stage I-III NSCLC patients treated with definitive radiotherapy. Validation was performed in an additional 220 NSCLC cases. After validation, 19 SNPs remained significant. A polygenic risk score (PRS) was generated to summarize the effect from validated SNPs. Significant improvements in discriminative ability were observed by adding the PRS into the clinical/epidemiological variable-based model. We then used 277 lymphoblastoid cell-lines to assess radiation sensitivity and eQTL relationships of the identified SNPs. Three genes (PRKCE,DDX58 and TNFSF7) were associated with radiation sensitivity. We concluded that inflammation-related genetic variants could contribute to the development of radiation-induced toxicities. These loci could assist in predicting those unfavorable events.

The transient expression of miR-203 and its inhibiting effects on skeletal muscle cell proliferation and differentiation

Previous studies have shown that miR-203 is a skin-specific microRNA (miRNA) with a profound role in skin cell differentiation. However, emerging microarray and deep sequencing data revealed that miR-203 is also expressed in embryonic skeletal muscle and myoblasts. In this study, we found that miR-203 was transiently upregulated in chicken embryos on days 10 to 16 (E10-E16) and was sharply downregulated and even not expressed after E16 in chicken embryonic skeletal muscle. Histological profiles and weight variations of embryo skeletal muscle revealed that miR-203 expression is correlated with muscle development. In vitro experiments showed that miR-203 exhibited downregulated expression during myoblast differentiation into myotubes. miR-203 overexpression inhibited myoblast proliferation and differentiation, whereas its loss-of-function increased myoblast proliferation and differentiation. During myogenesis, miR-203 can target and inhibit the expression of c-JUN and MEF2C, which were important for cell proliferation and muscle development, respectively. The overexpression of c-JUN significantly promoted myoblast proliferation. Conversely, knockdown of c-JUN by siRNA suppressed myoblast proliferation. In addition, the knockdown of MEF2C by siRNA significantly inhibited myoblast differentiation. Altogether, these data not only suggested that the expression of miR-203 is transitory during chicken skeletal muscle development but also showed a novel role of miR-203 in inhibiting skeletal muscle cell proliferation and differentiation by repressing c-JUN and MEF2C, respectively.

Precision measurement of the neutron twist-3 matrix element d(2)(n): probing color forces

Double-spin asymmetries and absolute cross sections were measured at large Bjorken x  (0.25≤x≤0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized (3)He target. In this dedicated experiment, the spin structure function g(2)((3)He) was determined with precision at large x, and the neutron twist-3 matrix element d(2)(n) was measured at ⟨Q(2)⟩ of 3.21 and 4.32  GeV(2)/c(2), with an absolute precision of about 10(-5). Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at ⟨Q(2)⟩=5  GeV(2)/c(2). Combining d(2)(n) and a newly extracted twist-4 matrix element f(2)(n), the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 30  MeV/fm in magnitude.

Measurement of the target-normal single-spin asymmetry in deep-inelastic scattering from the reaction (3)He(↑)(e,e')X

We report the first measurement of the target-normal single-spin asymmetry in deep-inelastic scattering from the inclusive reaction 3)He(↑)(e,e')X on a polarized (3)He gas target. Assuming time-reversal invariance, this asymmetry is strictly zero in the Born approximation but can be nonzero if two-photon-exchange contributions are included. The experiment, conducted at Jefferson Lab using a 5.89 GeV electron beam, covers a range of 1.7<W<2.9  GeV, 1.0<Q(2)<4.0  GeV(2) and 0.16<x<0.65. Neutron asymmetries were extracted using the effective nucleon polarization and measured proton-to-(3)He cross-section ratios. The measured neutron asymmetries are negative with an average value of (-1.09±0.38)×10(-2) for invariant mass W>2  GeV, which is nonzero at the 2.89σ level. Our measured asymmetry agrees both in sign and magnitude with a two-photon-exchange model prediction that uses input from the Sivers transverse momentum distribution obtained from semi-inclusive deep-inelastic scattering.

Matrine-induced apoptosis of human nasopharyngeal carcinoma cells via in vitro vascular endothelial growth factor-A/extracellular signal-regulated kinase1/2 pathway inactivation

Matrine, a main active extract from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines, such as malignant melanoma, breast cancer, and lung cancer. However, it is currently unclear whether matrine could also elicit an inhibitory effect on growth of nasopharyngeal carcinoma (NPC), let alone the possible molecular mechanisms. Therefore, in a previous study, we investigated matrine-induced proliferation inhibition and apoptosis in NPC cells. It was shown that proliferation of human NPC cells (CNE1 and CNE2) was significantly diminished by matrine in a dose- and time-dependent manner, and apoptosis was induced in both 2 NPC cells, particularly in CNE2 cells. Moreover, the increased apoptosis rate in matrine-treated CNE2 cells confirmed the proapoptotic activity of matrine. We further found that matrine treatment dose- and time-dependently reduced the levels of vascular endothelial growth factor-A (VEGF-A), and inactivated extracellular signal-regulated kinase1/2 (ERK1/2), followed by increased expression of downstream target caspase-3. Overall, we conclude that matrine could induce apoptosis of human NPC cells via VEGF-A/ERK1/2 pathway, which supports the potential use of matrine in clinically treating NPC.