Maintenance Therapy for Recurrent or Metastatic Cervical Cancer: A Multicenter, Cohort Study

PURPOSE/OBJECTIVE(S)

Maintenance therapy with alternative agents after chemotherapy was shown to improve the overall survival in some advanced cancers such as breast cancer, lung cancer, ovarian cancer and so on. However, maintenance therapy is not accepted as the standard treatment for recurrent/metastatic cervical cancer. Aim of this study is to elucidate the efficacy of maintenance therapy in cervical cancer and to explore the factors associated with the prognosis of recurrent or metastatic cervical cancer.

MATERIALS/METHODS

In this multicenter cohort study, we retrospectively collected patients with a diagnosis of either recurrent or stage IVB cervical cancer to receive first-line chemotherapy with or without maintenance therapy. Patients did not have disease progression with first-line chemotherapy and were divided into maintenance therapy group (Arm A) and conventional chemotherapy group (Arm B). Information on clinical characteristics, metastasis information, treatment outcome and survival of patients was collected using an electronic medical record system. The endpoints of the study were OS and PFS. Data were analyzed for general characteristics and survival using statistical software, and the results were considered statistically significant at P < 0.05.

RESULTS

Between January 2019 and July 2021, a total of 270 patients were enrolled from 6 institutions in China. 26 patients were excluded because of short treatment cycles (less than 3 cycles). Finally, a total of 66 patients in Arm A and 178 patients in Arm B were analyzed for survival. The addition of maintenance significantly prolonged overall survival. Overall survival at 3 year was 50.1% in Arm A and 27.8% in Arm B (median overall survival, ≥36 months vs. 22 months; P<0. 001). The median progression-free survival was 21 months in Arm A and 14 months in Arm B (P = 0.025). Univariate survival analysis showed that age, maintenance therapy, combined radiotherapy, and number of extra-pelvic metastases were associated with PFS. Further multifactorial analysis showed that maintenance therapy, combined radiotherapy, and number of extra-pelvic metastases were independent prognostic factors for patients with recurrent or metastatic cervical cancer.

CONCLUSION

The addition of maintenance therapy significantly prolonged overall survival as well as progression-free survival in patients with recurrent or metastatic cervical cancer and did not increase the incidence of serious adverse events. It is time to consider maintenance therapy as the standard treatment after conventional chemotherapy for recurrent or metastatic cervical cancer, rather than waiting for disease progression.

Metabolic Glycan Labeling in Primary Neurons Enabled by Unnatural Sugars with No S-Glyco-Modification

It is of great interest to probe glycosylation in primary neuron cultures. However, per-O-acetylated clickable unnatural sugars, which have been routinely utilized in metabolic glycan labeling (MGL) for analyzing glycans, showed cytotoxicity to cultured primary neurons and thus led to the speculation that MGL was not compatible with primary neuron cell cultures. Here, we uncovered that neuron cytotoxicity of per-O-acetylated unnatural sugars was related to their reactions with protein cysteines via non-enzymatic S-glyco-modification. The modified proteins were enriched in biological functions related to microtubule cytoskeleton organization, positive regulation of axon extension, neuron projection development, and axonogenesis. We thus established MGL in cultured primary neurons without cytotoxicity using S-glyco-modification-free unnatural sugars including ManNAz, 1,3-Pr2ManNAz, and 1,6-Pr2ManNAz, which allowed for visualization of cell-surface sialylated glycans, probing the dynamics of sialylation, and large-scale identification of sialylated N-linked glycoproteins and the modification sites in primary neurons. Particularly, a total of 505 sialylated N-glycosylation sites distributed on 345 glycoproteins were identified by 1,6-Pr2ManNAz.

[Long-term outcomes of 328 patients with of autism spectrum disorder after fecal microbiota transplantation]

Objective: To evaluate the efficacy and safety of fecal microbiota transplantation (FMT) in the treatment of autism spectrum disorder (ASD). Methods: A longitudinal study was conducted. Clinical data from ASD patients with gastrointestinal symptoms and who underwent FMT in the Tenth People's Hospital affiliated to Tongji University or Jinling Hospital between May 2012 to May 2021 were retrospectively collected. Scores derived from the autism behavior checklist (ABC), the childhood autism rating scale (CARS), the Bristol stool form scale (BSFS), and the gastrointestinal symptom rating scale (GSRS) were analyzed at baseline and at the 1st, 3rd, 6th, 12th, 24th, 36th, 48th and 60th month after FMT. Records of any adverse reactions were collected. Generalized estimating equations were used for analysis of data on time points before and after FMT. Results: A total of 328 patients met the inclusion criteria for this study. Their mean age was 6.1±3.4 years old. The cohort included 271 boys and 57 girls. The percentage of patients remaining in the study for post-treatment follow-up at the 1st, 3rd, 12th, 24th, 36th, 48th and 60th month were as follows: 303 (92.4%), 284 (86.7%), 213 (64.9%), 190 (57.9%), 143 (43.6%), 79 (24.1%), 46 (14.0%), 31 (9.5%). After FMT, the average ABC score was significantly improved in the first 36 months and remained improved at the 48th month. However, the average score was not significantly different from baseline by the 60th month (1st-36th month, P<0.001; 48th month, P=0.008; 60th month, P=0.108). The average CARS score improved significantly during the first 48 months and remained improved at the 60th month (1st-48th month, P<0.001; 60th month, P=0.010). The average BSFS score was also significantly improved in the first 36 months (with an accompanying stool morphology that resembled type 4). This improvement was maintained at the 48th month. However, the average score was similar to baseline at the 60th month (1st-36th month, P<0.001; 48th month, P=0.008; 60th month, P=0.109). The average GSRS score was significantly improved during the first 24 months, but not afterwards (1st-24th month, P<0.001; 36th month, P=0.209; 48th month, P=0.996; 60th month, P=0.668). The adverse events recorded during treatment included abdominal distension in 21 cases (6.4%), nausea in 14 cases (4.3%), vomiting in 9 cases (2.7%), abdominal pain in 15 cases (4.6%), diarrhea in 18 cases (5.5%), fever in 13 cases (4.0%), and excitement in 24 cases (7.3%). All adverse reactions were mild to moderate and improved immediately after suspension of FMT or on treatment of symptoms. No serious adverse reactions occurred. Conclusion: FMT has satisfactory long-term efficacy and safety for the treatment of ASD with gastrointestinal symptoms.

Expression of lncRNA AK058003 in esophageal carcinoma and analysis of its intervention effect

OBJECTIVE

The aim of this study was to investigate the expression of long non-coding ribonucleic acid (lncRNA) AK058003 in esophageal carcinoma (EC) tissues, and to analyze its intervention effect.

PATIENTS AND METHODS

The expression of lncRNA AK058003 in EC tissues and para-carcinoma tissues from 130 EC patients was detected via quantitative Polymerase Chain Reaction (qPCR). EC cell lines were selected for exogenous interference in lncRNA AK058003. Subsequently, the expression of lncRNA AK058003 in normal esophageal epithelial cell line (Het-1A) and EC cell lines (EC109, EC9706, KYSE-150, KYSE-30, and TE-1) was detected by qPCR. EC9706 cell lines with the highest expression of lncRNA AK058003 were selected and transfected with lncRNA AK058003 siRNA and lncRNA AK058003 control, respectively. After transfection, the expression of lncRNA AK058003 was determined using PCR. The changes in cell growth and proliferation were analyzed via cell growth curve and cell cycle assay. Meanwhile, the changes in cell migration and invasion were analyzed through wound healing assay. Protein expressions of matrix metalloproteinase-1 (MMP1) and MMP2 were determined by Western blot. Clinical data were collected from EC patients, and the association between lncRNA AK058003 expression and tumor-node-metastasis (TNM) stage was finally analyzed.

RESULTS

LncRNA AK058003 was highly expressed EC tissues compared with para-carcinoma tissues (p<0.01). Compared with Het-1A cells, the expression of lncRNA AK058003 was significantly higher in EC109, EC9706, KYSE-150, KYSE-30, and TE-1 cells, with highest level in EC9706 cells (p<0.05). The expression of lncRNA AK058003 remarkably declined in lncRNA AK058003 siRNA group compared with lncRNA AK058003 control group (p<0.001). Compared with lncRNA AK058003 control group, the proliferation of EC cells was significantly weakened in lncRNA AK058003 siRNA group, with the greatest difference at 3 d. Flow cytometry results revealed that cell cycle was arrested in G0/G1 phase in lncRNA AK058003 siRNA group. Wound healing assay indicated that the intercellular distance became large, and cell migration ability was evidently enhanced in lncRNA AK058003 siRNA group with time (p<0.05). Besides, the protein expressions of MMP1 and MMP2 were remarkably lower in lncRNA AK058003 siRNA group than those in lncRNA AK058003 control group. This indicated remarkably declined invasion and metastasis ability. In addition, the postoperative prognosis was significantly worse in patients with higher expression of lncRNA AK058003 (p<0.05). All these findings suggested that lncRNA AK058003 could serve as a biomarker for EC prognosis.

CONCLUSIONS

LncRNA AK058003 is highly expressed in EC patients, which promotes proliferation, migration, invasion, and metastasis of EC cells. In addition, the postoperative prognosis of EC patients with high expression of lncRNA AK058003 is relatively poor.

miR-382-3p Overexpression attenuates N-methyl-D-aspartate-induced HT22 cell apoptosis via the regulation of the RhoC/ROCK1 signaling pathway

miR-382-3p can regulate apoptosis through multiple pathways, but the mechanism remains unknown. In this experiment, we explored whether miR-382-3p can modulate the N-methyL-D-aspartate (NMDA)- induced HT22 cell apoptosis by regulating the RhoC/ROCK1 signaling pathway. An excitatory neurotoxicity model of HT22 cells was induced in vitro with 2 mmol/L NMDA. The cells were divided into normal control, NMDA-induced, NMDA + miR-382-3p mimic, and NMDA + miR-382-3p inhibitor groups. The 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) method, Real-time PCR, Western blot, and flow cytometry were performed to investigate the mechanisms. The results found that NMDA can increase the oxidative stress of HT22 cells in a dose-dependent manner, downregulate the expression of miR-382-3p, upregulate the expression of mRNA and protein abundance of ROCK1 and RhoC, increase the expression levels of proapoptotic proteins Bax, Caspase-3, and Caspase-9, increase the apoptosis of HT22 cells, and reduce the activity and survival rate of HT22 cells. Compared with the NMDA-induced group, the miR-382-3p mimic-transfected HT22 cells increased the expression of miR- 382-3p, reduced the expression of the mRNA and protein abundance of ROCK1 and RhoC, inhibited the expression of proapoptotic proteins Bax, Caspase-3, and Caspase-9, reduced the apoptosis of HT22 cells, and increased the activity and survival rate of HT22 cells. The results suggest that increasing the expression of miR-382-3p can inhibit the activity of the RhoC/ROCK1 signaling pathway, reduce the expression of proapoptotic proteins, reduce the oxidative stress and apoptosis of HT22 cells, and increase the activity and survival rate of HT22 cells.

Display of quintuple glucagon-like peptide 1 (28-36) nonapeptide on Bacillus subtilis spore for oral administration in the treatment of type 2 diabetes

AIMS

To develop an oral delivery system of glucagon-like peptide 1 (GLP-1) (28-36) for treating type-2 diabetes, B.S-GLP-1(28-36), a recombinant Bacillus subtilis spores transformed with a plasmid vector encoding five consecutive GLP-1 (28-36) nonapeptides with an enterokinase site was constructed.

METHODS AND RESULTS

GLP-1(28-36) nonapeptide was successfully expressed on the surface of B. subtilis spores and validated by Western blot and immunofluorescence. The therapeutic effect of oral administration of B.S-GLP-1(28-36) spores was evaluated in type 2 diabetic model mice. The efficacy of recombinant spores was examined for a period of 13 weeks after oral administration in diabetic mice. At the end of the sixth week, diabetic mice with oral administration of BS-GLP-1(28-36) spores showed decreased blood glucose levels from 2·4 × 10^{- 2}  mol l^-1 to 1·7 × 10^{- 2}  mol l^-1 . By the ninth week, the mean fasting blood glucose level in the experimental group was significantly lower than that in the control group 30 min after injection of pyruvate. At the end of the 10th week of oral administration, the blood glucose of the experimental group was significantly lower than that of the control group after intraperitoneal injection of glucose. By the 12th week, fasting blood glucose level and fasting insulin level were measured in all mice, the results showed that the recombinant spores increased the insulin sensitivity of mice.

CONCLUSIONS

The results of pathological observation showed that the recombinant spores also had a certain protective effect on the liver and islets of mice, and the content of GLP-1(28-36) in the pancreas of the experimental group was increased.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study revealed that GLP-1(28-36) nonapeptides can reduce blood glucose and play an important role in the treatment of type 2 diabetes.

Efficient production of coenzyme Q10 from acid hydrolysate of sweet sorghum juice by Rhodobacter sphaeroides

In order to achieve efficient bioconversion of biomass-derived sugars, acid hydrolysate of sweet sorghum juice (SSJAH) containing abundant fermentable sugars was used for coenzyme Q10 (CoQ10) fermentation by Rhodobacter sphaeroides CQ-09-1. The synthesis of CoQ10 was facilitated when the initial concentration of total sugar was 80.00 g L-1. And the highest CoQ10 titer was obtained when the pH and temperature were maintained at 7.00 and 30.00 °C, respectively. Moreover, corn steep powder (CSP) was proved to be an efficient nitrogen & salt supplement to SSJAH. Under the optimized conditions, the titer of CoQ10 reached 141.95 mg L-1 in a fed-batch fermentation. The CoQ10 titer reported was about two times higher than that obtained in the previous study using wild strains. This process introduces a potential way to produce CoQ10 using the concept of biorefinery, while making full use of sweet sorghum juice (SSJ).

Phosphoproteome profiling revealed abnormally phosphorylated AMPK and ATF2 involved in glucose metabolism and tumorigenesis of GH-PAs

PURPOSE

Protein phosphorylation plays a key role in tumorigenesis and progression. However, little is known about the phosphoproteome profiles of growth hormone-secreting pituitary adenomas (GH-PAs). The aim of this study was to identify critical biomarkers and signaling pathways that might play important roles in GH-PAs and may, therefore, represent potential therapeutic targets.

METHODS

The differential phosphoprotein expression patterns involved in GH-PAs were investigated by nano-LC-MS/MS in a group of samples. The phosphoprotein expression data were analyzed by bioinformatics. The expression levels of the candidate phosphorylated AMPK (ser496) and ATF2 (ser112) were validated by Western blot analysis in another group of samples.

RESULTS

A total of 1213 phosphorylated protein sites corresponding to 667 proteins were significantly different between GH-PAs and healthy pituitary glands. Among these phosphorylated sites, 871 exhibited lower levels of phosphorylation in GH-PAs. Moreover, 140 novel phosphosites corresponding to 93 proteins were differentially phosphorylated between GH-PAs and healthy pituitary glands, 101 of which showed decreased phosphorylation in GH-PAs. The majority of differentially expressed phosphorylated proteins were significantly enriched in glycolysis and the AMPK signaling pathway in GH-PAs. The AMPK signaling pathway was demonstrated to be inhibited in GH-PAs by pathway activity analysis (z score = - 2.324). Notably, the phosphorylated levels of AMPK (ser496) and ATF2 (ser112) were significantly lower in GH-PAs than in healthy pituitary glands.

CONCLUSION

These findings suggest that decreased phosphorylation of the AMPK/ATF2 pathway may be critical for glucose metabolism and tumorigenesis in GH-PAs.

3D Black-Blood Luminal Angiography Derived from High-Resolution MR Vessel Wall Imaging in Detecting MCA Stenosis: A Preliminary Study

BACKGROUND AND PURPOSE

3D high-resolution vessel wall imaging is increasingly used for intracranial arterial diseases. This study compared the diagnostic performance of black-blood luminal angiography derived from 3D vessel wall imaging with source images of vessel wall imaging and TOF-MRA in detecting middle cerebral artery stenosis.

MATERIALS AND METHODS

Sixty-two patients with suspected MCA atherosclerosis underwent TOF-MRA, vessel wall imaging, and CTA. Intracranial black-blood luminal angiography was created from source images of vessel wall imaging using minimum intensity projection. The degree and length of MCA stenosis were measured on source images of vessel wall imaging, TOF-MRA, and black-blood luminal angiography and compared using CTA as a reference standard.

RESULTS

The image quality of black-blood luminal angiography was diagnostic in most patients. The intra- and interobserver agreement for both stenosis degree and length measurements was excellent for black-blood luminal angiography. It was comparable with that of source images of vessel wall imaging in grading stenosis. Compared with TOF-MRA, black-blood luminal angiography showed significantly higher sensitivity for the detection of severe stenosis (89.3% versus 64.3%, P = .039) and higher specificity for the detection of occlusion (95.4% versus 84.6%, P = .039). Lesion length estimated on source images of vessel wall imaging was significantly greater than that measured by CTA and black-blood luminal angiography (P < .001 and P = .010).

CONCLUSIONS

Black-blood luminal angiography is better than TOF-MRA in detecting severe stenosis and occlusion of the MCA. Compared with source images of vessel wall imaging, it is more accurate in evaluating stenosis length. Black-blood luminal angiography can be produced as a derivative from vessel wall imaging and implemented as an adjunct to vessel wall imaging and TOF-MRA without extra acquisition time.

Effect of in ovo feeding of l-arginine on the hatchability, growth performance, gastrointestinal hormones, and jejunal digestive and absorptive capacity of posthatch broilers

This study was conducted to investigate the effects of in ovo feeding (IOF) of Arg solution on the hatchability, growth performance, gastrointestinal hormones, serum AA, activities of digestive enzymes, and mRNA expressions of sensing receptors and nutrient transporters in the jejunum of posthatch broilers. One thousand two hundred embryonated eggs with similar weight were randomly allocated to 5 groups consisting of 8 replicates of 40 eggs each. The 5 treatments were arranged as a noninjected control, a diluent-injected (0.75% NaCl solution) group, and Arg solution-injected groups with 0.5%, 1.0%, and 2.0% Arg, all dissolved in diluent. At 17.5 d of incubation, 0.6 mL of IOF solution was injected into the amniotic fluid of each egg of the injected groups. Results showed the hatchability of the 2% Arg group was lower (linear, = 0.025) than that of the other groups, and the BW of 21-d-old broilers increased (linear, = 0.008; quadratic, = 0.003) with increasing IOF concentration of Arg. The ADFI (linear, = 0.005; quadratic, = 0.001) and ADG (linear, = 0.010; quadratic, = 0.004) increased during d 1 to 21 with increasing IOF concentration of Arg. For 7- and 21-d-old broilers, the weights of digestive organs increased (linear, < 0.05) with increasing IOF concentrations of Arg; the greatest values were observed in the 1% Arg group. For 21-d-old broilers, IOF of the 1% Arg solution increased ( < 0.05) the concentrations of ghrelin and glucagon-like peptide 2; the activities of digestive enzymes, alkaline phosphatase, maltase, and sucrase in the jejunum; and the concentrations of serum AA of Val, Met, Ile, Leu, Arg, and Pro compared with those of the noninjected control and diluent-injected group. In ovo feeding of the 1% Arg solution also increased ( < 0.05) the mRNA expressions of jejunal sensing receptors of taste receptor type 1 members 1 and 3; the G protein-coupled receptor, class C, group 6, subtype A; nutrient transporters of solute carrier family 7, members 4, 6, and 7; sodium-glucose transporter 1; and fatty acid-binding protein 1. In conclusion, the 1% Arg solution was the appropriate injection level. In ovo feeding of the 1% Arg solution did not affect the hatchability but facilitated the release of gastrointestinal hormones, increasing the digestive and absorptive capacity and finally improving the growth performance of 21-d-old broilers. Therefore, IOF of the appropriate Arg solution could be an effective technology for regulating early nutrition supply and subsequent growth development in the poultry industry.

Uptake of 2,4-bis(Isopropylamino)-6-methylthio-s-triazine by Vetiver Grass (Chrysopogon zizanioides L.) from Hydroponic Media

2,4-bis(Isopropylamino)-6-methylthio-s-triazine (prometryn) poses a risk to aquatic environments in several countries, including China, where its use is widespread, particularly due to its chemical stability and biological toxicity. Vetiver grass (Chrysopogon zizanioides L.) was tested for its potential for phytoremediation of prometryn. Vetiver grass was grown in hydroponic media in a greenhouse, in the presence of prometryn, with appropriate controls. Plant uptake and removal of prometryn from the media were monitored for a period of 67 days. The results showed that the removal of the prometryn in the media was expedited by vetiver grass. The removal half-life (t1/2) was shortened by 11.5 days. Prometryn removal followed first-order kinetics (Ct = 1.8070e(-0.0601t)). This study demonstrated the potential of vetiver grass for the phytoremediation for prometryn.

Detection of carotid artery stenosis: a comparison between 2 unenhanced MRAs and dual-source CTA

BACKGROUND AND PURPOSE

Dual-source CTA and black-blood MRA are recently developed techniques for evaluating carotid stenosis. The purpose of this study was to compare dual-source CTA with black-blood MRA and conventional TOF MRA in both detecting carotid stenosis by using DSA as a reference standard and demonstrating plaque morphology.

MATERIALS AND METHODS

Thirty patients with suspected carotid artery stenosis underwent unenhanced MRA by using black-blood and TOF MRA and dual-source CTA. Source images from unenhanced MRAs and dual-source CTA were reconstructed with MIP or curved planar reconstruction. The degree of carotid artery stenosis was measured, and plaque surface morphology at the stenosis was analyzed and compared among different techniques.

RESULTS

Good correlation was observed for measuring the degree of carotid stenosis among dual-source CTA, black-blood MRA, TOF MRA, and DSA. Sensitivity and specificity for detecting severe stenosis were 100% and 97% with dual-source CTA, 100% and 95% with black-blood MRA, and 79% and 95% with TOF MRA. None of the 3 technologies resulted in stenosis of <50% being overestimated. Plaque surface irregularity or ulceration was more frequently detected with dual-source CTA and black-blood MRA than with TOF MRA and DSA.

CONCLUSIONS

This preliminary study shows that black-blood MRA is a promising technique, comparable with dual-source CTA and DSA, but better than TOF MRA, in the evaluation of carotid stenosis. Unlike dual-source CTA, black-blood MRA requires no intravenous contrast or radiation.

Graphene mode-locked femtosecond laser at 2 μm wavelength

We experimentally demonstrated a passively mode-locked femtosecond laser by using a graphene-based saturable absorber mirror (graphene SAM) in the spectral region of 2 μm. The graphene SAM was fabricated by transferring chemical-vapor-deposited, high-quality, and large-area graphene on a highly reflective plane mirror. Stable mode-locked laser pulses as short as 729 fs were obtained with a repetition rate of 98.7 MHz and an average output power of 60.2 mW at 2018 nm.

Levels and profiles of unintentionally produced persistent organic pollutants in surface soils from Shanxi province, China

Six species of unintentionally produced persistent organic pollutions comprised of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, polychlorinated biphenyls, polychlorinated naphthalenes, hexachlorobenzene and pentachlorobenzene in soils collected from Shanxi province, China were determined. The sum toxic equivalent ranged from 0.14 to 2.20 with an average of 0.94 pg TEQ/g. Polychlorinated dibenzo-p-dioxins/furans contributed the most toxic proportion to the total toxic equivalent. CB-126 was the most toxic contributor to polychlorinated biphenyls. CN66/67 and CN73 are the dominant toxic congeners to polychlorinated naphthalenes. From the patterns, it was speculated that thermal related industries were possible sources of unintentionally produced persistent organic pollutions.

Effect of salicylate on KCNQ4 of the guinea pig outer hair cell

Salicylate causes a moderate hearing loss and tinnitus in humans at high-dose levels. Salicylate-induced hearing loss has been attributed to impaired sound amplification by outer hair cells (OHCs) through its direct action on the OHC motility sensor and/or motor. However, there is a disparity of salicylate concentrations between the clinical and animal studies, i.e., extremely high extracellular concentrations of salicylate (from 1 to 10 mM) is required to produce a significant reduction of electromotility in animal studies. Such concentrations are above the clinical/physiological range for humans. Here, we showed that clinical/physiological concentration range of salicylate caused concentration-dependent and reversible reductions in I(K,n) (KCNQ4) and subsequent depolarization of OHCs. Salicylate reduced the maximal tail current of the activation curve of I(K,n) without altering the voltage-sensitivity (V(half)). The salicylate-induced reduction of I(K,n) was almost completely blocked by linopirdine (0.1 mM) and BaCl₂ (10 mM). Consistent with the finding in OHCs, salicylate significantly reduced KCNQ4-mediated current expressed in Chinese hamster ovarian (CHO) cells by comparable amplitude to OHCs without significantly shifting V(half). Nonstationary fluctuation analysis shows that salicylate significantly reduced the estimated single-channel current amplitude and numbers. Intracellular Ca²+ elevation resulting from cytoplasmic acidosis also contributes to the current reduction of I(K,n) (KCNQ4) of OHCs. These results indicate a different model for the salicylate-induced hearing loss through the reduction of KCNQ4 and subsequent depolarization of OHCs, which reduces the driving force for transduction current and electromotility. The major mechanism underlying the reduction of I(K,n) (KCNQ4) is the direct blocking action of salicylate on KCNQ4.

Elevated levels of serum antibodies against Saccharomyces cerevisiae mannan in patients with systemic lupus erythematosus

This study was undertaken to investigate whether levels of anti- Saccharomyces cerevisiae mannan antibodies (ASCMAs), a serological marker for Crohn’s disease, seronegative spondyloarthritis and Behcet’s disease, also correlate with systemic lupus erythematosus (SLE) in humans. Serum samples from healthy volunteers ( n = 152) and patients with SLE ( n = 40) were compared for ASCMA-IgA, -IgG and -IgM levels using enzyme linked immunosorbent assays. ASCMA-IgG, but not IgM and IgA, prevalence was significantly raised in active SLE patients (57.5%) compared with healthy controls (8.5%). ASCMA-IgG levels in SLE patients during remission were relatively lower, indicating a possible correlation with disease activity. These results differ from a previous study, which did not detect a difference between ASCMA levels in SLE patients and healthy control. It remains to be evaluated whether elevated ASCMA-levels are common to all rheumatic disorders.

Elevated expression of transmembrane IL-15 in immune cells correlates with the development of murine lupus: a potential target for immunotherapy against SLE

Presentation in trans by the Interleukin-15 receptor alpha chain (IL-15Ralpha) has been suggested as the main mechanism for IL-15 anchoring to the cell surface, but it is also evident that IL-15 can exist as a transmembrane protein. We herein demonstrate that replacement of the first 41 residues of human IL-15 (hIL-15) with Igkappa chain leader sequence resulted in secretion of most of the recombinant hIL-15 expressed in transfectant cells, thus identifying the transmembrane region of IL-15. A fusion protein (hIL-15Ralpha-Fc) between the extracellular domain of hIL-15Ralpha and the Fc fragment of IgG1 was prepared and shown to be able to bind with transmembrane IL-15 (tmIL-15). The level of tmIL-15 expression in macrophages, activated T cells and B cells from 6-month-old BXSB male mice, an animal model for systemic lupus erythematosus (SLE), was significantly increased compared with that from BXSB females or young males. In addition, hIL-15Ralpha-Fc was able to block the T cell stimulating and anti-apoptotic effect of the tmIL-15-positive BXSB macrophages in vitro. Intravenous administration of hIL-15Ralpha-Fc reduced the titre of autoantibodies against dsDNA and also proteinuria in aged BXSB males, implying that neutralization of IL-15 activity in vivo may be an effective way of treating SLE.

Regulatory Activity of Activated Murine Peripheral CD4+CD25?T Cells: A Possible Mechanism of Feedback Regulation on Adaptive Immunity

This study was undertaken to investigate the possibility that peripheral CD4+CD25- T cells, once fully activated, transiently obtain suppressive function against other T cells. CD4+CD25- T cells, isolated from splenocytes of BALB/c mice, were stimulated with anti-CD3 MoAb in the presence of feeder cells for 72 h. The activated CD4+ T cells (T(act)) thus obtained were able to inhibit the activation and proliferation of bystander CD4+ T cells in a non-MHC-restricted manner. T(act)-mediated suppression was cell contact dependent, reversible by exogenous IL-2 as well as anti-GITR antibody. Furthermore, adoptive transfer of T(act) cells significantly downregulated humoral response of BALB/c mice to s.c. immunization with ovalbumin. We argue that suppression mediated by activated CD4+CD25- T cells may play an important role in maintaining homeostasis of the immune system and preventing excessive T-cell responses in vivo.

Activation of Akt and ERK signalling pathways induced by etoposide confer chemoresistance in gastric cancer cells

AIMS

To identify whether phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase/extracellular-regulated protein kinases signalling pathways are implicated in the chemoresistance of gastric cancer and to explore the possible mechanisms.

METHODS

Gastric cancer cell lines SGC7901 and BGC823 were exposed to etoposide, Wortmannin+etoposide or PD98059+etoposide. Cell cycle distribution and cell apoptosis were detected using flow cytometry and Hoechst 33258 staining. Cells viability was determined by a colourimetric assay utilising 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). Akt activity was detected using non-radioactive immunoprecipitation-kinase assay. Western blotting was exploited to evaluate the level of phosphorylated ERK1/2 and expressions of c-Myc and p53 protein.

RESULTS

Etoposide suppressed the viability of SGC7901 and BGC823 cells in a time- and dose-dependent manner; PD98059 and Wortmannin were able to enhance the cytotoxicity of etoposide. The apoptotic levels of cells treated with Wortmannin+etoposide or PD98059+etoposide were significantly higher than those of cells treated with etoposide only. Phospho-ERK1/2, Akt activity and expression of c-Myc were significantly induced by etoposide in a time-dependent manner; moreover, there was a weak effect on the expression of p53 protein. Both Wortmannin and PD98059 elevated the level of p53 expression strikingly, however, only PD98059 suppressed the up-regulation trend of c-Myc expression induced by etoposide.

CONCLUSION

Chemotherapy reagent activated phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase/extracellular-regulated protein kinases signalling pathways, which decreased the chemotherapy sensitivity of gastric cancer cell lines SGC7901 and BGC823 via suppressing the expression of p53 and enhancing the expression of c-Myc. This may be one of the molecular mechanisms of gastric cancer chemoresistance.

Phenotypic and functional analysis of human T lymphocytes in early second- and third-trimester fetuses

This study was undertaken to investigate the phenotypic and functional status of T lymphocytes of human fetuses from early second- to third-trimester. Cord blood samples were obtained from 19 healthy human fetuses (gestation weeks: 18-36), by cordocentesis, and 16 term newborns (gestation weeks 37-42). Maternal and unrelated male blood samples were also taken as controls. Percentage of lymphocytes in fetal white blood cells was 79.3%, reducing to 40% by term birth, much higher than that of adults. Cord blood mononuclear cells (CBMC), prepared by density gradient centrifugation followed by lysis of erythrocytes, were stained using PE- or FITC-labelled monoclonal Abs and analysed by flow cytometry. The frequencies of CD3+ T cells in fetal (40.1%) and neonatal (42.4%) CBMC were significantly lower than that of men (59.6%) and pregnant women (53.6%). Proportions of CD8+ T cells (9.5%), gammadelta-T cells (0.5%) and NK cells (4.8%) in fetal CBMC were also lower than that of neonates (except gammadelta-T cells) and adults. A negative linear correlation (r = -0.609) between the ratio of CD4+/CD8+ T cells in fetal blood and gestation age could also be established. Fetal CBMC showed vigorous spontaneous proliferation but failed to respond to mitogen (PHA) or allogeneic stimulation in vitro. The fetal mononuclear cells were unable to produce IL-2, IL-4 or IFN-gamma, but spontaneously secreted IL-10, IL-6 and TNF-alphain vitro. Stimulation with PHA up-regulated the production of IL-10, IL-6 and TNF-alpha substantially.