Early exposure of high-dose interleukin-4 to tumor stroma reverses myeloid cell-mediated T-cell suppression

Myeloid-derived suppressor cells (MDSCs) inhibit T-cell activity and promote tumor growth in tumor-bearing hosts. We sought to determine how to prevent the generation of these cells and modulate anti-tumor immunity at different times during tumor growth. Interleukin-4 (IL-4), a cytokine closely associated with the differentiation of myeloid cells, was expressed locally at the tumor site with its dose and expression time tightly regulated by a tet-off system. Early exposure of high-dose IL-4 to the tumor stromal cells effectively prevented the generation of myeloid suppressor cells and led to a T-cell-mediated tumor rejection. However, IL-4 had no effect a few days after tumor growth, when myeloid suppressor cells had been generated and T cells were tolerized. Importantly, coinoculation of IL-4 receptor (IL-4R)-deficient tumor cells with IL-4R competent, but not IL-4R-deficient myeloid cells led to IL-4-mediated tumor regression in IL-4R-deficient mice, indicating that IL-4 acts directly on myeloid cells. These results show a novel way to prevent T cells from MDSC-induced suppression, with important indications for cancer therapy.

AKT1 polymorphisms are associated with tuberculosis in the Chinese population

AKT1, a serine/threonine kinase, plays a critical role in the controlling of intracellular growth of Mycobacterium tuberculosis. In this study, we investigated whether polymorphisms in AKT1 affect susceptibility to tuberculosis (TB). Two single nucleotide polymorphisms of AKT1, IVS3+18C>T and +726G>A were genotyped in Chinese patients with pulmonary TB by polymerase chain reaction-restriction fragment length polymorphism. Patients with pulmonary TB had significantly lower IVS3+18 C/C genotype and higher C/T genotype compared with age-, gender- and ethnically matched controls (P < 0.05). The T-A haplotype frequency was significantly higher in patients than in controls (P < 0.05). In conclusion, our result indicates that AKT1 polymorphisms are associated with susceptibility to pulmonary TB.

MicroRNA-25 functions in regulation of pigmentation by targeting the transcription factor MITF in Alpaca (Lama pacos) skin melanocytes

Although the influence of endocrine factors is well established, the molecular and cellular mechanisms controlling coat color are not completely understood. A major mechanism for post-transcriptional regulation of gene expression is through the action of microRNAs (miRNAs), which anneal to the 3' untranslated region of mRNAs in a sequence-specific fashion and either block translation or promote transcript degradation. In this study, we investigated the expression of miRNAs in the skin of alpacas with brown vs white coat color using a microarray screen; identified potential mRNA targets for identified miRNAs among coat color genes; and subsequently determined the ability of a specific, differentially expressed miRNA (miR-25) to suppress expression of micropthalmia-associated transcription factor (MITF), a predicted miR-25 target gene that regulates genes linked to coat color. Expression of 10 different miRNA species in the skin of alpacas with brown vs white coat color was identified from microarray screens. Of the 10 alpaca skin miRNAs identified, predicted binding sites in the 3' untranslated region of RNAs encoding for known genes linked to coat color were primarily for miR-25, but sites were also identified for miR-129 and miR-377. Potential miR-25 binding sites were present in transcripts encoding for 11 coat color genes, including MITF. An inverse relationship between transcript abundance for MITF and miR-25 was observed in skin samples collected from alpacas with white vs brown coat color. Furthermore, overexpression of miR-25 in cultured melanocytes reduced MITF mRNA and protein abundance and corresponding mRNA abundance for the MITF-regulated enzymes tyrosinase and tyrosinase-related protein 1. Results support a novel functional role for miRNA-25 in the regulation of gene expression linked to coat color.

Ruscogenin glycoside (Lm-3) isolated from Liriope muscari improves liver injury by dysfunctioning liver-infiltrating lymphocytes

The effects of ruscogenin 1-O-[β-d-glucopyranosyl(1 → 2)] [β-d-xylopyranosyl(1 → 3)]-β-d-fucopyranoside (Lm-3) and its aglycone, ruscogenin, on liver injury induced in mice by delayed-type hypersensitivity to picryl chloride have been investigated. Lm-3 and ruscogenin significantly decreased liver injury when given during the effector phase of the delayed-type hypersensitivity reaction. The pretreatment of nonparenchymal cells, but not hepatocytes, with Lm-3 or ruscogenin in-vitro caused a concentration- and time-dependent inhibition against the damage. Lm-3 showed a stronger inhibition against the damage than ruscogenin (IC50: Lm-3 6.3 times 10−10  m, ruscogenin 3.9 times 10−7  m). However, neither Lm-3 nor ruscogenin blocked the hepatotoxic potential of CCl4, when used to pretreat hepatocytes. Moreover, Lm-3 and ruscogenin inhibited concanavalin A-induced lymphocyte proliferation only at high concentrations. These results suggested that Lm-3 and ruscogenin improved the immunological liver injury by selectively causing dysfunction of the liver-infiltrating cells rather than by protecting hepatocyte membranes. Such characteristics would be significant for treating immunologically related liver diseases as well as for developing new drugs.

Effect of timing, dose and interstitial versus nanoparticle delivery of tumor necrosis factor alpha in combinatorial adjuvant cryosurgery treatment of ELT-3 uterine fibroid tumor

Cryosurgery has shown potential as a minimally invasive technology for tumor treatment. However, incomplete destruction followed by tumor recurrence after cryosurgery is a common drawback. This study characterizes several variables in the cryoadjuvant TNF-alpha enhancement of conservative cryosurgery (i.e. freezing to the visible edge) of ELT-3 (uterine leiomyoma) tumor in a female nude mouse model. The variables include pretreatment time, mode of TNF-alpha delivery (native vs. CYT-6091, a PEGylated 33 nm colloidal gold core nanoparticle) and dose of TNF-alpha. Survival and tumor growth delay were measured up to 30 days and showed: 1) pretreatment with TNF-alpha required 4 hours incubation prior to cryosurgery to produce a tumor growth delay over cryosurgery alone, and 2) CYT-6091 reduced the toxicity of TNF-alpha administration over intratumoral or peritumoral injection of native TNF-alpha. Taken together, 5 microgram TNF-alpha delivered by the nanodrug CYT-6091 4 hours prior to cryosurgery yielded a dramatic reduction in tumor growth over cryosurgery alone and in some cases even total remission of the tumor. However, some toxicity at higher doses (i.e. 5 micrograms) with CYT-6091 was noted compared to previous work in prostate (LNCaP) cancer grown in a male nude mouse. Potential reasons for this, including sex and weight of the animals are discussed. Further opportunities to optimize the TNF-alpha enhanced cryosurgical response of this tumor include dosing between 2 - 5 microgram at 4 hours prior to cryosurgery, and freezing beyond the visible edge of the tumor.

Smoking and risk of death due to pulmonary tuberculosis: a case-control comparison in 103 population centers in China

OBJECTIVE

To examine the relationship between smoking and the risk of tuberculosis (TB) mortality in a large population-based case-control study in China using an alternative control group selection design.

METHODS

During 1989-1991, a nationwide mortality survey was conducted of deaths among adults from 1986 to 1988. Surviving spouses or other informants provided detailed information about their own as well as the deceased person's smoking history. For the present study, all persons who died of TB at age > or =40 were used as cases, whereas all surviving spouses of deceased persons who died from causes other than those attributed to smoking were used as controls.

RESULTS

It was estimated that for 22.5% of men and 6.6% of women, smoking was a contributing factor for TB deaths. Although variations in TB death rates by smoking status were not obvious before the age of 60, these differences increased substantially with age thereafter. This trend occurred in both urban and rural areas, although rural TB death rates were double those observed in urban areas.

CONCLUSIONS

Tobacco smoking was associated with a large number of deaths from TB in China. The current study confirms results from previous studies about the relationship between smoking and TB mortality.

Variation of meat quality traits among five genotypes of chicken

The main objective of this study was to examine the diversity of meat quality traits among 5 chicken genotypes. The genotypes included 2 Chinese native breeds (Wenchang,WCH, and Xianju), 1 commercial broiler line (Avian, AV), 1 commercial layer line (Hy-Line Brown, HLB), and 1 Chinese commercial broiler line (Lingnanhuang, LNH) synthesized by exotic and native breeds, which were slaughtered at their market ages: 16, 7, 16, and 8 wk, respectively. The effects of genotype, muscle type, and sex on meat quality traits were examined. Birds from slow-growing genotypes (WCH, Xianju, and HLB) exhibited higher shear value, inosine-5'-monophosphate concentration, lower cook loss, and more fat than those from fast-growing genotypes (AV and LNH). Chickens from WCH possessed the lowest expressible moisture, cook loss, and the highest lipid (%) among the 3 slow-growing genotypes. The HLB birds were intermediate in expressible moisture and cook loss and lowest in lipid among all genotypes. The LNH cross birds were similar to AV broilers in most meat quality parameters, although they had a lower shear force value and higher fat content than AV broilers. Breast muscle had higher expressible moisture, shear force, protein (%), inosine-5'-monophosphate content, lower cook loss, and lipid (%) than leg muscle. Muscles from male chickens had higher expressible moisture than those from the females. Variability of meat quality characteristics is mainly related to genotype and muscle type differences.

Reliability of environmental sampling to quantify Mycobacterium avium subspecies paratuberculosis on California free-stall dairies

The reliability of environmental sampling to quantify Mycobacterium avium ssp. paratuberculosis (MAP) based on collector and time was evaluated. Fecal slurry samples were collected using a standardized protocol simultaneously by 2 collectors of different experience levels. Samples were collected from 30 cow pens on 4 dairies every other day on 3 occasions while cow movements between pens were minimal. The 4 study herds had moderate MAP seroprevalence and were housed in free-stall dairies in central California. Results of testing the environmental samples for MAP using PCR and culture were strongly correlated. The reliability of environmental sampling simultaneously by different collectors as estimated by the intraclass correlation coefficient was excellent (81%) for PCR and good (67%) for culture and may justify comparison of quantitative results of samples collected by different investigators. The reliability of environmental sampling over a 5-d period was good (67 and 64% for PCR and culture results, respectively), which justifies the utility of environmental sampling to identify pens with a high MAP bioburden between routine cow pen changes on a dairy. Environmental sampling of free-stall pens using the standardized sampling protocol yielded comparable PCR and culture results across collectors with different experience levels and at different times within a 5-d period.

Small Interfering RNA-Mediated Silencing of Heat Shock Protein 27 (HSP27) Increases Chemosensitivity to Paclitaxel by Increasing Production of Reactive Oxygen Species in Human Ovarian Cancer Cells (HO8910)

Increasing evidence indicates that reactive oxygen species (ROS) are involved in paclitaxel cytotoxicity. Modulating the oxidant–antioxidant status of tumour cells may increase the antitumour activity of paclitaxel. The cytoprotective roles of heat shock protein 27 (HSP27) include chaperoning cellular proteins, regulating apoptotic signalling and modulating oxidative stress. Immunohistochemical staining for HSP27 in human ovarian cancer specimens showed HSP27 was associated with aggressive malignant ovarian disease. Small interfering RNA (siRNA) was used to down-regulate HSP27 in human ovarian cancer cells (HO8910). Reduction of HSP27 expression increased the in vitro chemosensitivity of HO8910 cells to paclitaxel and increased paclitaxel-induced apoptosis and ROS production, although the ROS scavenger, N-acetyl-l-cysteine, partly offset the effects of HSP27 siRNA. Thus, gene knock-down of HSP27 offsets the role of this protein in resisting oxidant stress, thereby indirectly increasing the sensitivity of cells to paclitaxel. The siRNA-induced knock-down of HSP27 could be a novel and potent strategy to help overcome chemotherapeutic resistance to paclitaxel in epithelial ovarian cancer cells.

Complexation of uranium(VI) with malonate at variable temperatures

The complexation between uranium(VI) and malonate in 1.05 mol kg−1 NaClO4 was studied at variable temperatures (25, 35, 45, 55 and 70 °C). The formation constants of three successive complexes, UO2(OOCCH2COO), UO2(OOCCH2COO)2 2− and UO2(OOCCH2COO)3 4−, and the molar enthalpies of complexation were determined by potentiometry and calorimetry. The heat capacity of the complexation, Δ Co p,m(MLj), is calculated to be 96 ± 12, 195 ± 15 and 267 ± 22 J K−1 mol−1 for j=1, 2 and 3, respectively. Extended X-ray Absorption Fine Structure Spectroscopy helped to characterize the coordination modes in the complexes in solution. UV/Vis absorption and luminescence spectra at different temperatures provided qualitative information on the temperature effect. The effect of temperature on the complexation between uranium(VI) and malonate is discussed in terms of the electrostatic model and compared with the complexation between uranium(VI) and acetate.

The DEAD-box protein p72 regulates ERalpha-/oestrogen-dependent transcription and cell growth, and is associated with improved survival in ERalpha-positive breast cancer

The DEAD-box RNA helicases p68 (DDX5) and p72 (DDX17) have been shown to act as transcriptional co-activators for a diverse range of transcription factors, including estrogen receptor α (ERα). Here, we show that, although both proteins interact with and co-activate ERα in reporter gene assays, siRNA-mediated knockdown of p72, but not p68, results in a significant inhibition of estrogen-dependent transcription of endogenous ERα-responsive genes and estrogen-dependent growth of MCF-7 and ZR75-1 breast cancer cells. Furthermore, immunohistochemical staining of ERα-positive primary breast cancers for p68 and p72 indicate that p72 expression is associated with an increased period of relapse-free and overall survival (p=0.006 and p=0.016 respectively), as well as being inversely associated with Her2 expression (p=0.008). Conversely, p68 shows no association with relapse-free period, or overall, survival but it is associated with an increased expression of Her2 (p=0.001), AIB-1 (p<0.001) and higher tumour grade (p=0.044). Our data thus highlight a crucial role for p72 in ERα co-activation and estrogen-dependent cell growth and provide evidence in support of distinct but important roles for both p68 and p72 in regulating ERα activity in breast cancer.

Infusion of mesenchymal stem cells and rapamycin synergize to attenuate alloimmune responses and promote cardiac allograft tolerance

The inherent immunosuppressive properties and low immunogenicity of mesenchymal stems cells (MSCs) suggested their therapeutic potential in transplantation. We investigated whether MSCs could prolong allograft survival. Treatment involving infusion of MSCs into BALB/c recipients 24 hours after receiving a heart allograft from a C57BL/6 donor significantly abated rejection and doubled graft mean survival time compared to untreated recipients. Furthermore, combination therapy of MSCs and low-dose Rapamycin (Rapa) achieved long-term heart graft survival (>100 days) with normal histology. The treated recipients readily accepted donor skin grafts but rejected third-party skin grafts, indicating the establishment of tolerance. Tolerant recipients exhibited neither intragraft nor circulating antidonor antibodies, but demonstrated significantly high frequencies of both tolerogenic dendritic cells (Tol-DCs) and CD4(+)CD25(+)Foxp3(+)T cells in the spleens. Infusion of GFP(+)C57BL/6-MSCs in combination with Rapa revealed that the GFP-MSCs accumulated in the lymphoid organs and grafts of tolerant recipients. Thus, engraftment of infused MSCs within the recipient's lymphoid organs and allograft appeared to be instrumental in the induction of allograft-specific tolerance when administered in combination with a subtherapeutic dose of Rapamycin. This study supports the clinical applicability of MSCs in transplantation.

Effect of Dose, Timing and Delivery of Tumor Necrosis Factor Alpha as an Adjuvant in Cryosurgery of ELT-3 Uterine Leiomyoma (Fibroid) Tumor

Uterine leiomyoma (fibroid or myoma) is the most common indication for hysterectomy in premenopausal women. Cryomyolysis is a uterus sparing procedure in which a myoma is frozen by a cryoprobe, thereby causing tissue necrosis upon thawing and eventual reduction in myoma size. Unfortunately, although the iceball is readily visualized (by ultrasound-US or magnetic resonance-MR), the tissue at the periphery of the iceball is not completely destroyed. One potential solution to this problem is the use of cryosurgical adjuvants that increase cryosurgical image guidance and efficacy. Previous work in our lab has shown that TNF-α (native or as the nanodrug, CYT-6091, Cytimmune Sciences, Inc.) can act synergistically with cryosurgery to destroy all prostate cancer within an iceball. Building on this work, the current study was designed to test TNF-α as an adjuvant in an in vivo model of uterine fibroid (ELT-3) in a nude mouse. The aims of this study are to characterize in vivo: 1) the destruction of the uterine fibroid over time after cryosurgery; 2) the effect of TNF-α pre-treatment on enhancement of cryosurgery; 3) the effect of TNF-α dose, pre-treatment time and mode of delivery on the above and to note any toxicities. ELT–3 rat uterine fibroid cells were grown in the hind limb of female nude mice. TNF-α at various dose (2μg and 5μg) was administered at 1, 2 and 4 hours before cryotreatment in native or CYT-6091. Native TNF-α was injected either intra-tumorally or peri-tumorally. Injecting TNF-α solution into the center of the tumor comprised the intra-tumoral approach. For peri-tumoral injection, TNF-α solution was injected at each one of eight evenly distributed points spanning the circumference of the tumor base. CYT-6091 was administered by i.v. injection only. Cryosurgery was performed with a modified 1 mm diameter cryoprobe tip (−120°C). Freezing was allowed to continue to the visible edge of the tumor. Injury was assessed by measuring tumor-growth delay. Baseline tumor size was measured on day 0; fold-changes in tumor size are reported relative to size at day 0. Toxicity was evaluated by survival rate. Groups were 4–6 animals in each group. The data suggests that pre-treatment with TNF-α before cryosurgery significantly enhances visually guided destruction of uterine leiomyoma, and that the dose, timing and mode of delivery are important variables in optimization of this combination treatment. First, it was observed that at least four hours pretreatment with TNF-α is required to obtain the synergistic effect of TNF-α and cryoinjury. Second, peri-tumoral injection of native TNF-α, was the most effective delivery method to enhance cryoinjury at low dose (2μg), however it was also the most toxic method at high dose (5μg). On the other hand, CYT-6091, although less effective than peri-tumoral injection at 2μg, was the safest delivery mode (0% lethality at 2μg; 33% at 5μg). Finally, CYT-6091 delivery at 5μg with cryosurgery resulted in a dramatic tumor growth delay compared with cryosurgery alone. Therefore, i.v. injection of CYT-6091 followed by cryosurgery allowed the highest dose of TNF-α, the least toxicity and the best overall myoma reduction. Funding: R01 CA075284, American Medical Systems, Inc. TNF-α and CYT-6091: Cytimmune Sciences, Inc.

High-sensitivity KRAS mutation detection in colorectal and lung cancer using SURVEYOR Nuclease scanning

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Background: Mutations of the KRAS gene in colorectal and lung cancers have been associated with lack of response to epidermal growth factor receptor (EGFR) inhibitor therapies. Here we describe a highly sensitive assay that identifies mutations by scanning the entire coding region of KRAS exons 2 and 3 using SURVEYOR Nuclease, an endonuclease that cleaves double-stranded heteroduplex DNA at base pair mismatch sites. Methods: DNA was extracted from formalin-fixed paraffin- embedded tissue sections from a set of 30 colorectal and lung cancer samples. Two amplicons covering the coding and splice junction regions of the KRAS gene exons 2 and 3 were PCR-amplified, hybridized to allow heteroduplex formation, incubated with SURVEYOR Nuclease and analyzed on the WAVE-HS DHPLC system. The sensitivity of SURVEYOR Nuclease mutation detection was assessed by creating serial dilutions of 50:50 mixtures of original PCR products from mutant samples with wild type amplicons from control DNA. Results: 6 samples were identified as KRAS mutant by WAVE-HS profiles containing two fragment peaks in addition to the full length amplicon peak, indicating SURVEYOR Nuclease cleavage at a mismatch site. Mutations were found in both exon 2 (codons 12, 13) and exon 3 (codon 59). Sequencing confirmed the KRAS mutations in these samples. Levels of mutant DNA as low as 2% (1 ng/ul) were identified by this method, consistent with other SURVEYOR-based assays. Conclusions: SURVEYOR Nuclease technology is a sensitive and comprehensive method for detecting mutation in KRAS.

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Spermatogonial stem cells: unlimited potential

Recent reports have demonstrated that adult cells can be reprogrammed to pluripotency, but mostly with genes delivered using retroviruses. Some of the genes are cancer causing; thus, these adult-derived embryonic stem (ES)-like cells cannot be used for therapy to cure human diseases. Remarkably, it has also been demonstrated recently by several groups that, in mice, spermatogonial stem cells (SSCs) can be reprogrammed to ES-like cells without the necessity of exogenously added genes. SSCs constitute one of the most important stem cell systems in the body, not only because they produce spermatozoa that transmit genetic information from generation to generation, but also because of the recent studies showing their remarkable plasticity. Very little is known about SSCs in humans, except for the earlier work of Clermont and colleagues who demonstrated that there are Adark and Apale spermatogonia, with the Adark referred to as the reserve stem cells and the Apale being the renewing stem cells. We now demonstrate that G protein-coupled receptor 125 (GPR125) may be a marker for human SSCs. Putative human SSCs can also be reprogrammed to pluripotency. We were able to achieve this result without the addition of genes, suggesting that human SSCs have considerable potential for cell-based, autologous organ regeneration therapy for various diseases.