Archetypal clustering reveals physiological mechanisms linking milk yield and fertility in dairy cattle

Fertility in dairy cattle has declined as an unintended consequence of single trait selection for high milk yield. The unfavorable genetic correlation between milk yield and fertility is now well-documented, however, the underlying physiological mechanisms are still uncertain. To understand the relationship between these traits, we developed a method that clusters variants with similar patterns of effects and, after the integration of gene expression data, identifies the genes through which they are likely to act. Biological processes that are enriched in the genes of each cluster were then identified. We identified several clusters with unique patterns of effects. One of the clusters included variants associated with increased milk yield and decreased fertility, where the 'archetypal' variant (i.e., the one with the largest effect) was associated with the gene GC, while others were associated with TRIM32, LRRK2, and U6. These genes have been linked to transcription and alternative splicing, suggesting that these processes are likely contributors to the unfavorable relationship between the 2 traits. Another cluster, with archetypal variant near DGAT1 and including variants associated with CDH2, BTRC, SFRP2, ZFHX3, and SLITRK5, appeared to affect milk yield but have little effect on fertility. These genes have been linked to insulin, adipose tissue, and energy metabolism. A third cluster with archetypal variant near ZNF613 and including variants associated with ROBO1, EFNA5, PALLD, GPC6, and PTPRT were associated with fertility but not milk yield. These genes have been linked to GnRH neuronal migration, embryonic development, and/or ovarian function. The use of archetypal clustering to group variants with similar patterns of effects may assist in identifying the biological processes underlying correlated traits. The method is hypothesis-generating and requires experimental confirmation. However, we have uncovered several novel mechanisms potentially affecting milk production and fertility such as GnRH neuronal migration. We anticipate our method to be a starting point for experimental research into novel pathways which have been previously unexplored within the context of dairy production.

Integrative analysis reveals the recurrent genetic etiologies in idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is increasingly recognized as a chronic, progressive and fatal lung disease with an unknown etiology. Current studies focus on revealing the genetic factors in the risk of IPF, making the integrative analysis of genetic variations and transcriptomic alterations of substantial value.

AIM

This study aimed to improve the understanding of the molecular basis of IPF through an integrative analysis of whole-exome sequencing (WES), bulk RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) data.

METHODS

WES is a powerful tool for studying the genetic basis of IPF, allowing for the identification of genetic variants that may be associated with the development of the disease. RNA-seq data provide a comprehensive view of the transcriptional changes in IPF patients, while scRNA-seq data offer a more granule view of cell-type-specific alterations.

RESULTS

In this study, we identified a comprehensive mutational landscape of recurrent genomic and transcriptomic variations, including single-nucleotide polymorphisms, CNVs and differentially expressed genes, in IPF populations, which may play a significant role in the development and progression of IPF.

CONCLUSIONS

Our study provided valuable insights into the genetic and transcriptomic variations associated with IPF, revealing changes in gene expression that may contribute to disease development and progression. These findings highlight the importance of an integrative approach to understanding the molecular mechanisms underlying IPF and may pave the way for identifying potential therapeutic targets.

[Short-term efficacy and safety observation of standardized mite allergen extract rush subcutaneous immunotherapy for allergic rhinitis: a prospective study]

Objective: To conduct a comparative analysis of the efficacy, safety, and cytokine changes associated with three distinct dose escalation regimens of allergen-specific immunotherapy (AIT), and to provide valuable insights into the implementation of safer and more effective accelerated immunotherapy in clinical practice. Methods: A prospective study of subcutaneous immunotherapy (SCIT) was conducted at Renmin Hospital of Wuhan University, involving patients with allergic rhinitis visited from 2019 to 2022. Participants were allocated to one of three treatment groups based on their preferences: conventional immunotherapy (CIT, 23 cases), cluster immunotherapy (CLIT, 25 cases), or rush immunotherapy (RIT, 18 cases). The RIT group received a single subcutaneous injection of 150 mg of omalizumab one week before commencing treatment. Subjective evaluation indices, including the Combined Symptom and Medication Score (CSMS), Visual Analogue Scale (VAS), and single symptom score, were recorded alongside objective evaluation indices (e.g., sIgE, tIgE, Th1/2 and Th17 cytokines) and adverse reactions. Assessments were conducted at baseline, and at 1, 7, and 15 weeks after treatment. SPSS 22.0 software was used for data processing and analysis. Results: The study included a total of 66 patients, comprising 37 males and 29 females, who completed the treatment regimen. In all three groups, CSMS and VAS scores showed significant reductions at 1, 7, and 15 weeks post-treatment (all P<0.05). Notably, the RIT group demonstrated a significantly lower VAS score (4.33±0.94) compared to the CIT (9.48±1.37) and CLIT (9.44±1.33) groups at 1 week post-treatment (P<0.05). Additionally, the RIT group (0.62±0.23) exhibited a lower CSMS score than the CIT (1.54±0.21) and CLIT (1.06±0.22) groups at 15 weeks post-treatment (P<0.05). Furthermore, at the point of reaching the maintenance dose, the RIT group (0.61±0.20) demonstrated superior improvement in nasal itching symptoms compared to the CIT (1.78±0.38) and CLIT groups (1.56±0.32), with P<0.05. The incidence of local adverse reactions in the RIT group (36/11.76%) was lower than that in the CIT (69/20.00%) and CLIT groups (62/16.53%), with P<0.05. Notably, none of the three groups reported grade 3/4 systemic adverse reactions, and there was no statistically significant difference in systemic adverse reactions among the three groups. Following treatment, IL-4, IL-5, IL-6, IL-17, sIgE, sIgE/tIgE, and Eos% exhibited varying degrees of decrease in all three groups, whereas IL-10, TNF, and IFN-γ did not show significant changes. Conclusions: All three distinct dose escalation regimens of SCIT demonstrated substantial clinical efficacy. Of note, the approach of combining a single injection of omalizumab with RIT significantly improved early-stage efficacy and exhibited the advantages of safety, effectiveness, and convenience, establishing it as a reliable immunotherapy method.

Physical mapping of QTL associated with agronomic and end-use quality traits in spring wheat under conventional and organic management systems

Using phenotypic data of four biparental spring wheat populations evaluated at multiple environments under two management systems, we discovered 152 QTL and 22 QTL hotspots, of which two QTL accounted for up to 37% and 58% of the phenotypic variance, consistently detected in all environments, and fell within genomic regions harboring known genes. Identification of the physical positions of quantitative trait loci (QTL) would be highly useful for developing functional markers and comparing QTL results across multiple independent studies. The objectives of the present study were to map and characterize QTL associated with nine agronomic and end-use quality traits (tillering ability, plant height, lodging, grain yield, grain protein content, thousand kernel weight, test weight, sedimentation volume, and falling number) in hard red spring wheat recombinant inbred lines (RILs) using the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq v2.0 physical map. We evaluated a total of 698 RILs from four populations derived from crosses involving seven parents at 3-8 conventionally (high N) and organically (low N) managed field environments. Using the phenotypic data combined across all environments per management, and the physical map between 1058 and 6526 markers per population, we identified 152 QTL associated with the nine traits, of which 29 had moderate and 2 with major effects. Forty-nine of the 152 QTL mapped across 22 QTL hotspot regions with each region coincident to 2-6 traits. Some of the QTL hotspots were physically located close to known genes. QSv.dms-1A and QPht.dms-4B.1 individually explained up to 37% and 58% of the variation in sedimentation volume and plant height, respectively, and had very large LOD scores that varied from 19.0 to 35.7 and from 16.7 to 55.9, respectively. We consistently detected both QTL in the combined and all individual environments, laying solid ground for further characterization and possibly for cloning.

Physical Mapping of QTL in Four Spring Wheat Populations under Conventional and Organic Management Systems. I. Earliness

In previous studies, we reported quantitative trait loci (QTL) associated with the heading, flowering, and maturity time in four hard red spring wheat recombinant inbred line (RIL) populations but the results are scattered in population-specific genetic maps, which is challenging to exploit efficiently in breeding. Here, we mapped and characterized QTL associated with these three earliness traits using the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq v2.0 physical map. Our data consisted of (i) 6526 single nucleotide polymorphisms (SNPs) and two traits evaluated at five conventionally managed environments in the 'Cutler' × 'AC Barrie' population; (ii) 3158 SNPs and two traits evaluated across three organic and seven conventional managements in the 'Attila' × 'CDC Go' population; (iii) 5731 SilicoDArT and SNP markers and the three traits evaluated at four conventional and organic management systems in the 'Peace' × 'Carberry' population; and (iv) 1058 SNPs and two traits evaluated across two conventionally and organically managed environments in the 'Peace' × 'CDC Stanley' population. Using composite interval mapping, the phenotypic data across all environments, and the IWGSC RefSeq v2.0 physical maps, we identified a total of 44 QTL associated with days to heading (11), flowering (10), and maturity (23). Fifteen of the 44 QTL were common to both conventional and organic management systems, and the remaining QTL were specific to either the conventional (21) or organic (8) management systems. Some QTL harbor known genes, including the Vrn-A1, Vrn-B1, Rht-A1, and Rht-B1 that regulate photoperiodism, flowering time, and plant height in wheat, which lays a solid basis for cloning and further characterization.

[Clinical analysis of 126 patients with coronavirus disease 2019 with pharyngeal symptoms]

Objective: To investigate the clinical characteristics of patients with coronavirus disease 2019 (COVID-19) with pharyngeal symptoms. Methods: From January 10 to May 15, 2020, clinical data of 1 228 patients with COVID-19 in Renmin Hospital of Wuhan University was collected (554 males and 674 females, with the range of age from 10 to 95 years old, the average age was 55.2 years old). The patients were divided into pharyngeal symptoms group (PS, 126 cases) and non-pharyngeal symptoms group (Non-PS, 1 102 cases) according to the presence or absence of pharyngeal symptoms such as pharyngalgia, pharyngeal dryness, pharyngeal itching, and pharyngeal foreign body sensation. The clinical data in terms of age, sex, medical history, duration of symptoms, treatment time, clinical classification, pulmonary imaging findings, whole blood cell count, serum hypersensitivity C-reactive protein, C-reactive protein, procalcitonin were statistically analyzed between the two groups. Chi-square, Fisher's exact test and Mann-Whitney U test were used for statistical analysis. Results: The most common pharyngeal symptoms were pharyngalgia (59.52%, 75/126), followed by foreign body sensation (23.02%, 29/126), pharyngeal dryness (8.73%, 11/126), and itching (8.73%, 11/126). The median age of the patients in the PS group was 51.50 years old, which was less than 57.50 years old in the non-PS group, showing a significant difference (P<0.05). The female cases accounted for 65.08% (82/126), which was higher than 53.72% (592/1 102) of the non-PS group (P<0.05). The incidence of bilateral lung inflammation confirmed by CT images was 73.81% (93/126), which was significantly lower than 83.48% (920/1 102) in the non-PS group (P<0.05). No significant differences were shown in the proportion of patients with clinical types, treatment days, duration of symptoms, white blood cell count, lymphocyte count, lymphocyte percentage, eosinophil count, eosinophil percentage, hypersensitive C-reactive protein, C-reactive protein, D-dimer, procalcitonin and other indicators (P>0.05). Conclusions: The incidence of pharyngeal symptoms in patients with COVID-19 is 10.26%. Most of these symptoms occur before or at the same time as the common symptoms of the disease. Therefore, patients with such symptoms may bring a greater risk of infection to otolaryngologist. According to the current clinical classification criteria, pharyngeal symptoms have no obvious correlation with the degree of the disease; but the presence of pharyngeal symptoms may suggest a milder clinical presentation and a better prognosis.

The use of mid-infrared spectra to map genes affecting milk composition

The aim of this study was to investigate the feasibility of using mid-infrared (MIR) spectroscopy analysis of milk samples to increase the power and precision of genome-wide association studies (GWAS) for milk composition and to better distinguish linked quantitative trait loci (QTL). To achieve this goal, we analyzed phenotypic data of milk composition traits, related MIR spectra, and genotypic data comprising 626,777 SNP on 5,202 Holstein, Jersey, and crossbred cows. We performed a conventional GWAS on protein, lactose, fat, and fatty acid concentrations in milk, a GWAS on individual MIR wavenumbers, and a partial least squares regression (PLS), which is equivalent to a multi-trait GWAS, exploiting MIR data simultaneously to predict SNP genotypes. The PLS detected most of the QTL identified using single-trait GWAS, usually with a higher significance value, as well as previously undetected QTL for milk composition. Each QTL tends to have a different pattern of effects across the MIR spectrum and this explains the increased power. Because SNP tracking different QTL tend to have different patterns of effect, it was possible to distinguish closely linked QTL. Overall, the results of this study suggest that using MIR data through either GWAS or PLS analysis applied to genomic data can provide a powerful tool to distinguish milk composition QTL.

[Epidemiological investigation and analysis of allergic rhinitis among 6-12 years old children in Zaoyang City of Hubei Province]

Objective:The aim of this study is to investigate the epidemiological characteristics of allergic rhinitis(AR) among 6-12 years old children in Zaoyang.Method:All the children aged from 6 to 12 years old from 2 primary schools in Zaoyang in June 2018 were randomly selected as the research objects.The AR questionnaire was designed, and the epidemiological investigation was carried out. The results were analyzed by SPSS 20.0 software.Result:The prevalence rate of children aged 6-12 in Zaoyang was 13.7%,the prevalence rate of girls was 11.9%,and the prevalence rate of boys was 15.3%. The prevalence rate of boys was higher than that of girls,but the difference was not statistically significant(χ²=3.033,P>0.05).Univariate analysis showed that the factors related to AR were age(t=2.729,P<0.01), family history of allergic diseases (χ²=172.067,P<0.01),exposure to smoking or dust environment (χ²=43.091,P<0.01),exposure to smoking environment during pregnancy (χ²=6.09,P<0.05) and pet feeding history (χ²=9.473,P<0.01).Conclusion:The incidence of allergic rhinitis among 6-12 years old children in Zaoyang is high,age,family history of allergic diseasese,exposure to smoking or dust environment,exposure to smoking environment during pregnancy,and pet feeding history are risk factors for the incidence of allergic rhinitis in children.

[Expression and significance of polymeric immunoglobulin receptor in nasal polyps]

Objective:To explore the expression of polymeric immunoglobulin receptor in nasal polyps of patients with chronic rhinosinusitis with nasal polyps, and to investigateits relationship with the pathogenesis of nasal polyps. Method:Thirty-six specimens of nasal polyps were harvested patients were selected for the control group who had operation of nasal septal construction in the corresponding time period. The pIgR and IgA expression in nasal polyps and normal nasal inferior turbinate mucosa were detected by immunohistochemistry，and the real-time reverse transcription（RT-PCR） were used to detect the level of pIgR，IgA，RORc and Foxp3 mRNA expression in nasal polyps and normal nasal inferior turbinate mucosa. The association between pIgR mRNA and their association with the number of EOS，RORc mRNA，Foxp3 mRNA were analyzed，respectively． Result:The expression of pIgR in the nasal polyps was significantly lowerer than that in control group, and the result was statistically significant(P<0.05)；Compared with nasal polyps with no eosinophils, the expression levels of pIgR in the nasal polyps with eosinophils was lower\, and the result was statistically significant(P<0.05).The expression of IgA in the nasal polyps was significantly higherthan that in control , and the result was statistically significant(P<0.05).Compared with control, the mRNA expression of pIgR and Foxp3 in the nasal polyps were significantly lower，while the expression levels of IgA mRNA and Foxp3 mRNA in the nasal polyps was significantly higher compared to controls, and the result was statistically significant(P<0.05).In nasal polyps ,pIgR mRNA expression was correlated with RORc mRNA (P<0.05，r=-0.79)，and there was no correlation between pIgR mRNA and Foxp3 mRNA（P>0.05，r=0.36）. Conclusion:It was proved that pIgR down-regulation play an important role in the development of nasal polyps．.

A novel mutation of dipeptidyl aminopeptidase-like protein-6 in a family with suspicious idiopathic ventricular fibrillation

BACKGROUND

Sudden cardiac death (SCD) occurs in a broad spectrum of cardiac pathologies and is an important cause of mortality in the general population. Idiopathic ventricular fibrillation (IVF) is a rare but important factor resulting in SCD. It is diagnosed in a resuscitated cardiac arrest victim underlying unknown cause, with documented ventricular fibrillation. Previous studies have demonstrated that mutations in dipeptidyl aminopeptidase-like protein-6 (DPP6) and cardiac sodium channel Nav1.5 (SCN5A) are the most important genetic factors involve in IVF.

AIM

By using whole sequencing to identify the genetic lesion of a family with suspicious idiopathic ventricular fibrillation.

DESIGN

Prospective genetic study.

METHODS

In this study, we employed whole-exome sequencing in combination with arrhythmia-related gene filtering to identify the genetic lesion for a family suffering from suspicious IVF, syncope and SCD. We then generated the plasmids of DPP6-pcDNA3.1+ (WT and c.1578G>C/p.Q526H). Kv4.3-pcDNA3.1+ was co-transfected together with/without DPP6-pcDNA3.1+ (WT and/or c.1578G>C/p.Q526H) into HEK293 cells to perform the patch clamp experiments.

RESULTS

A novel missense mutation (c.1578G>C/p.Q526H) of DPP6 was identified and co-segregated with affected patients in this family. Patch clamp experiments suggested that this novel mutation might result in a gain of function and disturb the efflux of potassium ion.

CONCLUSION

Our study not only reported the second missense mutation of DPP6 in heart disease and expanded the spectrum of DPP6 mutations, but also contribute to the genetic diagnosis and counseling of families with suspicious IVF, syncope and SCD.

Morphology dependence of the thermal transport properties of single-walled carbon nanotube thin films

The thermal transport properties of random network, single-walled carbon nanotube (SWNT) films were assessed using Raman spectroscopy. Two types of SWNT films were investigated: single-layer and stacked. The single-layer films were fabricated by aerosol chemical vapour deposition and subsequent direct dry deposition, while the stacked films were prepared by placing the single-layer films on top of one another. The anisotropy of the network structures of each of these films was evaluated based on the angular dependence of the optical absorbance spectra. The results show that the anisotropy of the films decreases with increasing film thickness in the case of the single-layer films, and that the film anisotropy is preserved during the stacking process. The sheet thermal conductance is proportional to the SWNT area density in the case of stacked films, but is reduced with increasing thickness in the case of single-layer films. This effect is explained by a change in the network morphology from a two-dimensional anisotropic structure to the more isotropic structure. This work demonstrates the fabrication of low-density films with high sheet thermal conductance through the stacking of thin SWNT films.

[Application of directed acyclic graphs in control of confounding]

Observational study is a method most commonly used in the etiology study of epidemiology, but confounders, always distort the true causality between exposure and outcome when local inferencing. In order to eliminate these confounding, the determining of variables which need to be adjusted become a key issue. Directed acyclic graph(DAG)could visualize complex causality, provide a simple and intuitive way to identify the confounding, and convert it into the finding of the minimal sufficient adjustment for the control of confounding. On the one hand, directed acyclic graph can choose less variables, which increase statistical efficiency of the analysis. On the other hand, it could help avoiding variables that is not measured or with missing values. In a word, the directed acyclic graph could facilitate the reveal of the real causality effectively.

[Effect of the FOXP3 gene methylation status in pathogenesis of patients with allergic rhinitis]

Objective: To analyze the mRNA expression level and the methylation status of FOXP3 gene in peripheral blood of patients with allergic rhinitis(AR) and explore the roles of FOXP3 gene in the pathogenesis of AR.Method:According to inclusion and exclusion criteria,10 AR patients,10 AR patients received SIT treatment for over one year,10 healthy controls were recruited for this study.Bisulfate sequencing technology(BSP) was used to detect the different methyation status of FOXP3 gene in peripheral blood between AR patients and controls. Real time fluorescence quantitative reverse transcription-polymerase chain reaction(RT-PCR) was used to detect different levels of FOXP3 mRNA in peripheral blood between AR patients and controls.Result:VAS scores of AR patients with SIT is much lower than that of AR patients. The expression levels of FOXP3 mRNA in AR patients are significantly lower compared to controls and AR patients with SIT(P <0.05). The methylation levels of AR is significantly higher compared to healthy controls and AR patients with SIT(P <0.05), whereas the methylation levels of AR patients with SIT is significantly higher compared to controls.Conclusion:The methylation levels of -127 and -250 CpG island on FOXP3 promoter in peripheral blood of AR patients may be associated with allergic rhinitis, and SIT may attenuate symptoms of AR by regulating the methylation levels of FOXP3 promoter.

[Analysis of characteristics and factors affecting the recurrence of esophageal cancer within the first year after surgery]

OBJECTIVE

To analyze the characteristics and factors affecting the recurrence in esophageal cancer within the first year after esophagectomy.

METHODS

We reviewed retrospectively the clinical and follow-up data of 320 patients who underwent surgical treatment from April 2009 to April 2013 in Sichuan Provincial Cancer Hospital.

RESULTS

72 cases (72/320, 22.5%) had tumor recurrence within the first year after surgery. The average recurrence time was 6.89±3.53 months and the median recurrence time was 6.02 months. Univariate analysis showed that T stage, N stage, G grade, and pathological stage are related to the recurrence (P<0.05 for all). Logistic regression analysis showed that pathological stage is an independent risk factor for recurrence (P=0.002). There were 46 cases (46/72, 63.9%) of local recurrence and 26 cases (26/72, 36.1%) of distant metastasis. Among the 46 cases of local recurrence, 27 cases (27/46, 58.7%) had upper mediastinal lymph node metastasis. Among the 26 cases of distant metastasis, there were 11 cases (11/26, 42.3%) of pulmonary metastasis. Among the 72 cases of recurrence, the average number of dissected lymph nodes and involved nodes were 29.40±11.41 and 4.37±5.65, respectively, in patients with distant metastasis, and 21.18±10.37 and 1.91±2.14, respectively, in patients with local recurrence. Both the number of dissected and involved lymph nodes were significantly higher in the patients with distant metastasis (P<0.05).

CONCLUSIONS

Lymph node metastasis is the most common pattern of recent relapse after esophagectomy, and pathological stage is an independent risk factor for recurrence within the first year after surgery. Standardized lymph node dissection and rational treatment strategy is the key measures to reduce early recurrence of esophageal cancer.

HBV-induced ROS accumulation promotes hepatocarcinogenesis through Snail-mediated epigenetic silencing of SOCS3

Interleukin-6 (IL-6) has been demonstrated to be involved in Hepatitis B virus (HBV)-associated hepatocarcinogenesis through activation of the STAT3 pathway. The sustained activation of the IL-6/STAT3 pathway is frequently associated with repression of SOCS3, which is both a target gene and a negative regulator of STAT3. However, the silencing mechanism of SOCS3 in hepatocellular carcinoma (HCC) remains to be elucidated. Here, we showed that the repression of SOCS3 and sustained activation of IL-6/STAT3 pathway in HBV-producing HCC cells were caused by HBV-induced mitochondrial ROS accumulation. Mechanistic studies revealed that ROS-mediated DNA methylation resulted in the silencing of SOCS3. Decreased SOCS3 expression significantly promoted the proliferation of HCC cells and growth of tumor xenografts in mice. Further studies revealed that HBV-induced ROS accumulation upregulated the expression of the transcription factor, Snail, which bound to the E-boxes of SOCS3 promoter and mediated the epigenetic silencing of SOCS3 in association with DNMT1 and HDAC1. In addition, we found that the expression of Snail and SOCS3 were inversely correlated in HBV-associated HCC patients, suggesting that SOCS3 and/or Snail could be used as prognostic markers in HCC pathogenesis. Taken together, our data show that HBV-induced mitochondrial ROS production represses SOCS3 expression through Snail-mediated epigenetic silencing, leading to the sustained activation of IL-6/STAT3 pathway and ultimately contributing to hepatocarcinogenesis.

Downregulation of COMMD1 by miR-205 promotes a positive feedback loop for amplifying inflammatory- and stemness-associated properties of cancer cells

Sustained activation of nuclear factor-κB (NF-κB) in cancer cells has been shown to promote inflammation, expansion of cancer stem cell (CSC) population, and tumor development. In contrast, recent studies reveal that CSCs exhibit increased inflammation due to constitutive NF-κB activation; however, the underlying molecular mechanism remains unclear. In the present study, the analysis of microarray data revealed upregulation of NF-κB-regulated pro-inflammatory genes and downregulation of copper metabolism MURR1 domain-containing 1 (COMMD1) during the enrichment for stemness in SAS head and neck squamous-cell carcinoma (HNSCC) cells. The 3′-UTR of COMMD1 mRNA contains microRNA (miR)-205 target site. Parallel studies with HNSCC and NSCLC cells indicated that miR-205 is upregulated upon NF-κB activation and suppresses COMMD1 expression in stemness-enriched cancer cells. COMMD1 negatively regulates the inflammatory responses induced by TLR agonists, IL-1β, and TNF-α by targeting RelA for degradation. The shRNA-mediated downregulation of COMMD1 in cancer cells enhanced inflammatory response, generating favorable conditions for macrophage recruitment. In addition, genes associated with stemness were also upregulated in these cells, which exhibited increased potential for anchorage-independent growth. Furthermore, COMMD1 downregulation promoted in vivo tumorigenesis and tumor growth, and tumors derived from COMMD1-knockdown cells displayed elevated level of NF-κB activation, increased expression of inflammatory- and stemness-associated genes, and contain expanded population of tumor-associated leukocytes and stemness-enriched cancer cells. These results suggest that COMMD1 downregulation by miR-205 promotes tumor development by modulating a positive feedback loop that amplifies inflammatory- and stemness-associated properties of cancer cells.

TIFA, an inflammatory signaling adaptor, is tumor suppressive for liver cancer

TIFA (TNF receptor associated factor (TRAF)-interacting protein with a Forkhead-associated (FHA) domain), also called T2BP, was first identified using a yeast two-hybrid screening. TIFA contains a FHA domain, which directly binds phosphothreonine and phosphoserine, and a consensus TRAF6-binding motif. TIFA-mediated oligomerization and poly-ubiquitinylation of TRAF6 mediates signaling downstream of the Tumor necrosis factor alpha receptor 1 (TNFaR-I) and interleukin-1/Toll-like receptor 4 (TLR4) pathways. Examining TIFA expression in hepatocellular carcinoma (HCC) tissues microarrays, we noted marked decreases TIFA reactivity in tumor versus control samples. In agreement, we found that HCC cell lines show reduced TIFA expression levels versus normal liver controls. Reconstituting TIFA expression in HCC cell lines promoted two independent apoptosis signaling pathways: the induction of p53 and cell cycle arrest, and the activation of caspase-8 and caspase-3. In contrast, the expression of a non-oligomerizing mutant of TIFA impacted cells minimally, and suppression of TIFA expression protected cells from apoptosis. Mice bearing TIFA overexpression hepatocellular xenografts develop smaller tumors versus TIFA mutant tumors; terminal deoxynucleotidyl transferase dUTP nick end labeling staining demonstrates increased cell apoptosis, and decreased proliferation, reflecting cell cycle arrest. Interestingly, p53 has a greater role in decreased proliferation than cell death, as it appeared dispensable for TIFA-induced cell killing. The findings demonstrate a novel suppressive role of TIFA in HCC progression via promotion of cell death independent of p53.

Knockdown of H19 enhances differentiation capacity to epidermis of parthenogenetic embryonic stem cells

Parthenogenetic embryonic stem (pES) cells are pluripotent stem cells derived from artificially activated oocytes without embryo destruction, thus eliciting less ethic concerns, and have been demonstrated promising for autologous stem cell therapy. However, pES cells could carry inappropriate imprinting such as relatively high expression of H19, a paternal imprinted gene, and may negatively influence their lineage differentiation. We show that knockdown of H19 by shRNA in mouse pES cells does not alter self-renewal and expression of genes associated with pluripotency. We find that down-regulation of H19 promotes differentiation of pES cells to epidermis. In addition, H19 depletion also facilitates differentiation of pES cells to cardiomyocytes and strong heart-like beating. Our data support the notion that reduction of H19 improves pES cell differentiation in the lineages of ectoderm and mesoderm, and provide further evidence suggesting that defective imprinting can be manipulated to allow potential application of pES cells for stem cell therapy.

97 MAGNITUDE AND SPECIFICITY OF EFFECTS OF MATERNAL AND PATERNAL GENOMES ON THE FETO-PLACENTAL UNIT

The placenta, a major determinant of fetal growth in eutherians, facilitates maternal-fetal cross talk and mediates programming of postnatal phenotype via genetic and epigenetic mechanisms. However, magnitude and specificity of effects of maternal and paternal genomes on placental and fetal phenotype and their relationships are unclear. Using an outbred bovine intra-species model with well-defined Bos taurus taurus and Bos taurus indicus maternal and paternal genetics, we generated purebred and reciprocal cross fetuses (Animal Ethics No. S-094-2005) to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects (maternal weight and post-conception maternal weight gain) on 41 gross and histomorphological feto-placental parameters. Analysis of data from 73 fetuses recovered at midgestation (Day 153) with general linear models (Xiang et al. 2014 JBMR http://dx.doi.org/10.1002/jbmr.2263) using the GLM procedure of R version 22.14 (R Development Core Team, Vienna, Austria) revealed that maternal and paternal genome combined explained the highest proportion of variation (47.2–99.5%) in 30 investigated parameters with significant (P < 0.05–0.0001) models. Fetal sex accounted for up to 32.2% (P < 0.05–0.0001) and nongenetic maternal effects for up to 25.1% (P < 0.05–0.001) of variation in 11 and 14 parameters, respectively. Partitioning of parental (epi)genome variation showed that the maternal genome predominantly contributed to variation in gross (80.3–95.7%; P < 0.05–0.0001) and histomorphological (51.5–82.1%; P < 0.05–0.0001) placental parameters, fetal weight (54.1%; P < 0.0001), and fetal organ weights (43.7–73.1%; P < 0.05–0.0001), whereas the paternal genome predominantly contributed to fetal fluids weight (73.0%; P < 0.001), umbilical cord weight (73.9%; P < 0.05) and length (73.2%; P < 0.01), and placental (69.6%; P < 0.05) and umbilical cord (83.2%; P < 0.0001) efficiency. Our finding that the maternal genome determined placental phenotype (i.e. nutrient source) and the paternal genome determined umbilical cord and fetal fluid phenotype (i.e. nutrient flow) is in line with predicted expression patterns of genomic imprinting effects by both maternal-offspring coadaptation (Wolf and Hager 2006 PLoS Biol. 4, e380) and conflict-of-interest (Moore and Haig 1991 Trends Genet 7, 45–49) hypotheses in the feto-placental unit. Furthermore, there were 4 maternal genome determined relationships between placental weights and umbilical cord phenotype (P < 0.05–0.0001) and 28 paternal genome and/or fetal sex-determined relationships between fetus-, organ- and fetal fluid weights and umbilical cord phenotype (P < 0.05–0.0001). The finding of specific relationships between placenta and fetus merging in clusters differentiated by maternal and paternal genome effects suggests the existence of (epi)genetic-regulated morphological modules within the feto-placental unit.Funded by the JS Davies Bequest.

Ox-LDL increases OX40L in endothelial cells through a LOX-1-dependent mechanism

Oxidative low-density lipoprotein (Ox-LDL) is a key risk factor for the development of atherosclerosis, and it can stimulate the expression of a variety of inflammatory signals. As a new and highly sensitive inflammation index, OX40L may be a key to understanding the mechanisms that regulate interactions between cells within the vessel wall and inflammatory mediators during the development of atherosclerosis. To investigate whether Ox-LDL regulates OX40L expression through an oxidized LDL-1 receptor (LOX-1)-mediated mechanism, we investigated the effect of different concentrations of Ox-LDL (50, 100, 150 µg/mL) on endothelial cell proliferation and apoptosis. Stimulation with Ox-LDL increased OX40L protein 1.44-fold and mRNA 4.0-fold in endothelial cells, and these effects were inhibited by blocking LOX-1. These results indicate that LOX-1 plays an important role in the chronic inflammatory process in blood vessel walls. Inhibiting LOX-1 may reduce blood vessel inflammation and provide a therapeutic option to limit atherosclerosis progression.

Involvement of nuclear factor κB (NF-κB) in the downregulation of cyclooxygenase-2 (COX-2) by genistein in gastric cancer cells

Genistein induces growth inhibition in various human cancer cell lines but its mechanism of action remains unknown. This study determined whether the effect of genistein is mediated via suppression of cyclo-oxygenase (COX)-2 protein, and elucidated the mechanism of action of this effect in the human gastric cancer cell line BGC-823. Genistein treatment inhibited cell proliferation and induced apoptosis in a dose- and time-dependent manner; Western blotting analysis indicated a significant dose-dependent decrease in COX-2 protein levels. Genistein treatment exerted a significant inhibitory effect on activation of the transcription factor nuclear factor κB (NF-κB). Additionally, the NF-κB inhibitor pyrrolidine dithiocarbamate caused a reduction in COX-2 protein levels and NF-κB activation, similar to the effect of genistein. Suppression of COX-2 protein may be important for the antiproliferative and proapoptotic effects of genistein in BGC-823 cells, and these effects may be partly mediated through the NF-κB pathway.

Downregulation of transcription factor SOX2 in cancer stem cells suppresses growth and metastasis of lung cancer

Background:

The cancer stem cell hypothesis suggests that neoplastic clones are maintained exclusively by a small subpopulation of cells, which have indefinite proliferation and differentiation potentials and give rise to phenotypically diverse cancer cells. Cancer stem cells have been isolated by their ability to efflux Hoechst 33342 dye and are referred to as the ‘side population’ (SP).

Methods and results:

The Hoechst efflux assay was used to isolate and characterize the SP from murine D121 lung carcinoma cells. Here, we demonstrated that D121-SP cells contain cancer stem cell characteristics, that is, upregulation of the transcription factors SOX2 and Oct 4 in D121-SP cells. In addition, the migration of D121-SP was decreased, and apoptosis of D121-SP was upregulated following knocking down of SOX2 in D121 cells. Importantly, downregulation of SOX2 in D121 cells markedly suppressed their metastatic potential in syngeneic mice.

Conclusions:

These results suggest that the SP is an enriched source of lung tumour cells with stem cell properties and that SOX2 has an important role in maintaining stem cell properties and functions that may be a potential target for effective lung cancer therapy.

The role of proto-oncogene Fra-1 in remodeling the tumor microenvironment in support of breast tumor cell invasion and progression

A growing body of evidence indicates that interactions between neoplastic cells and tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) are crucial in promoting tumor cell invasion and progression. Macrophages play an ambiguous role in these processes since this M1 phenotype correlates with tumoricidal capacity whereas TAMs of M2 phenotype exert tumor-promoting effects. Here, we provide evidence that interactions between mouse breast tumor cells and TAMs remodel the TME, leading to upregulation of Fra-1, a member of the FOS family of transcription factor. In turn, this proto-oncogene initiates activation of the IL-6/JAK/Stat3 signaling pathway. This creates a malignant switch in breast tumor cells, leading to increased release of pro-angiogenic factors MMP-9, VEGF and TGF-β from tumor cells and intensified invasion and progression of breast cancer. Proof of concept for the crucial role played by transcription factor Fra-1 in regulating these processes was established by specific knockdown of Fra-1 with siRNA which resulted in marked suppression of tumor cell invasion, angiogenesis and metastasis in a mouse breast cancer model. Such a strategy could eventually lead to future efficacious treatments of metastatic breast cancer.

DNA vaccines designed to inhibit tumor growth by suppression of angiogenesis

The development of new blood vessels, i.e. angiogenesis, is a rate-limiting step in the development of tumors since tumor growth is generally limited to 1-2 mm3 in the absence of a blood supply. Thus, the inhibition of tumor growth by attacking the tumor's vascular supply offers a primary target for antiangiogenic intervention by DNA-based vaccines. Here, we describe two novel orally delivered DNA vaccines which suppress tumor angiogenesis and induce a robust cell-mediated immune response that provides for long-lived protection against melanoma, colon, breast and non-small-cell lung carcinoma in mouse model systems. These vaccines, which are delivered by attenuated Salmonella typhimurium to secondary lymphoid organs, are directed against such targets as vascular endothelial growth factor receptor 2 (FLK-1) and transcription factor Fos-related antigen 1 (Fra-1). Both vaccines break peripheral T cell tolerance against these self-antigens and induce a robust T cell-mediated immune response leading to suppression of tumor angiogenesis and resulting in effective suppression of tumor growth and metastases. Such research efforts may open up new possibilities for the rational design of future DNA vaccines effective for the prevention and treatment of cancer.

DNA vaccines suppress angiogenesis and protect against growth of breast cancer metastases

Two novel oral DNA-based vaccines provide immune protection against breast cancer in mouse model systems. These vaccines are delivered by attenuated Salmonella typhimurium to secondary lymphoid organs and are directed against novel targets such as transcription factor Fos-related antigen 1 (Fra-1) and endoglin (CD105). Both vaccines elicit suppression of angiogenesis in the breast tumor vasculature and break peripheral tolerance by eliciting potent cell-mediated protective immunity against these tumor self-antigens resulting in effective suppression of breast tumor growth and metastasis.

MIG (CXCL9) chemokine gene therapy combines with antibody-cytokine fusion protein to suppress growth and dissemination of murine colon carcinoma

The induction of a CTL response capable of eradicating disseminated tumor metastases and the establishment of a persistent tumor-protective immunity remain major goals of cancer immunotherapy. Here, we demonstrate for the first time that the combination of interleukin 2 (IL-2) targeted to the tumor microenvironment by a recombinant antibody-IL-2 fusion protein (huKS1/4-IL-2) with gene therapy by the murine chemokine MIG (CXCL9) markedly reduced s.c. tumor burden and decisively suppressed dissemination of experimental lung metastases of CT26-KSA colon carcinoma in syngeneic BALB/c mice. This combined therapy significantly prolonged the life span of these mice 3-4-fold by concurrently delivering MIG and IL-2 to the tumor site and thereby achieving chemoattraction of T cells together with their activation. The antitumor effect obtained was mediated predominantly by MHC class I antigen-restricted CD8(+) T cells with help from MHC class II antigen-restricted CD4(+) T lymphocytes. In addition, the MIG chemokine also induced angiostatic effects in the tumor vasculature. Taken together, this combination of MIG chemokine gene therapy with tumor-targeted cytokine IL-2 provides an approach for the rational design of novel cancer immunotherapy modalities.

An oral DNA vaccine against human carcinoembryonic antigen (CEA) prevents growth and dissemination of Lewis lung carcinoma in CEA transgenic mice

A DNA vaccine encoding human carcinoembryonic antigen (CEA) broke peripheral T-cell tolerance toward this tumor self-antigen expressed by Lewis lung carcinoma stably transduced with CEA in C57BL/6J mice transgenic for CEA. This vaccine, delivered by oral gavage with an attenuated strain of Salmonella typhimurium (SL7207), and boosted with an antibody-IL2 fusion protein, induced tumor-protective immunity mediated by MHC class I antigen-restricted CD8(+) T cells, resulting in eradication of subcutaneous tumors in 100% of mice and prevention of experimental pulmonary metastases in 75% of experimental animals. Both CTL and antigen-presenting dendritic cells were activated as indicated by a decisive increase in their respective activation markers CD2, CD25, CD28 as well as CD48 and CD80. The antitumor effects of this CEA-based DNA vaccine obtained in prophylactic settings, suggest that this approach could lead to the rational design of effective treatment modalities for human lung cancer.

A dual-function DNA vaccine encoding carcinoembryonic antigen and CD40 ligand trimer induces T cell-mediated protective immunity against colon cancer in carcinoembryonic antigen-transgenic mice

A carcinoembryonic Ag (CEA)-based DNA vaccine encoding both CEA and CD40 ligand trimer achieved effective tumor-protective immunity against murine colon carcinoma in CEA-transgenic mice by activating both naive T cells and dendritic cells. Peripheral T cell tolerance to CEA was broken in a prophylactic model by this novel, dual-function DNA vaccine, whose efficacy was further enhanced by boosts with a recombinant Ab-IL-2 fusion protein (huKS1/4-IL-2). These conclusions are supported by four lines of evidence. First, a lethal challenge of MC38-CEA-KS Ag murine colon carcinoma cells was for the first time completely rejected in 100% of experimental animals treated by oral gavage of this DNA vaccine carried by attenuated Salmonella typhimurium, followed by five boosts with huKS1/4-IL-2. Second, specific activation of dendritic cells was indicated by their marked up-regulation in expression of costimulatory molecules B7.1 (CD80), B7.2 (CD86), and ICAM-1. Third, a decisive increase over control values was observed in both MHC class I Ag-restricted cytotoxicity of CTLs from successfully vaccinated mice and secretion of proinflammatory cytokines IFN-gamma and IL-12. Fourth, activation of CTLs was augmented, as indicated by up-regulation of activity markers LFA-1, CD25, CD28, and CD69. Taken together, these results suggest that a dual-function DNA vaccine encoding CEA and CD40 ligand trimer combined with tumor-targeted IL-2 may be a promising strategy for the rational development of DNA-based cancer vaccines for future clinical applications.

Targeted interleukin 2 therapy enhances protective immunity induced by an autologous oral DNA vaccine against murine melanoma

We demonstrate that a mouse-human chimeric anti-ganglioside GD2-interleukin (IL)-2 fusion protein (ch14.18-IL2) substantially amplifies tumor-protective immunity against murine melanoma induced by an autologous oral DNA vaccine containing the murine ubiquitin gene fused to murine melanoma peptide epitopes gp100(25-35) and TRP-2(181-188). This combination therapy led to the complete rejection of a lethal challenge with B78D14 murine melanoma cells in six of eight mice and a marked suppression of s.c. tumor growth in the two remaining animals. The tumor-protective immunity was mediated by MHC class I antigen- restricted CD8(+) T cells together with CD4(+) T cell help, which was required only for tumor cell killing in the effector phase of the immune response. A single oral vaccination with the DNA vaccine, which was carried by attenuated Salmonella typhimurium, was equally as effective as three such vaccinations applied at 2-week intervals. The immunological mechanisms involved in this antitumor effect were suggested by a decisively increased secretion of tumor necrosis factor alpha TNFTnTNa and IFN-gamma from CD4(+) and CD8(+) T cells and a markedly up-regulated expression on CD8(+) T cells of high-affinity IL-2 receptor alpha chain (CD25), costimulatory molecule CD28, and adhesion molecule lymphocyte function-associated antigen-2 (LFA-2/CD2). Additionally, the combination therapy induced increased expression of costimulatory molecules B7.1 and CD48 on murine antigen-presenting cells. Taken together, our results suggest that IL-2 targeted to the tumor microenvironment by a specific antibody-IL-2 fusion protein is a potent enhancer of tumor-protective immunity induced by an oral DNA vaccine that may ultimately enhance the chances of success in its clinical application.

Protective immunity against human carcinoembryonic antigen (CEA) induced by an oral DNA vaccine in CEA-transgenic mice

Peripheral T-cell tolerance toward human carcinoembryonic self-antigen (CEA) was broken in CEA-transgenic C57BL/6J mice by an oral CEA-based DNA vaccine. This vaccine, delivered by the live, attenuated AroA- strain of Salmonella typhimurium (SL7207), induced tumor-protective immunity mediated by MHC class I-restricted CD8+ T cells. Activation of these T cells was indicated by increased secretion of proinflammatory cytokines IFN-gamma, interleukin (IL)-12 and granulocyte/macrophage-colony stimulating factor, as well as specific tumor rejection and growth suppression in vaccinated CEA-transgenic mice after a lethal challenge with murine MC38 colon carcinoma cells. These tumor cells were double transfected with CEA and the human epithelial cell adhesion molecule (Ep-CAM)/KSA and consequently served as a docking site for a recombinant antibody-IL2 fusion protein (KS1/4-IL2) recognizing KSA. Importantly, the efficacy of the tumor-protective immune response was markedly increased by boosts with this antibody-IL2 fusion protein, resulting in more effective tumor rejection coupled with increased expression of costimulatory molecules B7.2/B7.2 and intercellular adhesion molecule 1 (ICAM-1) on dendritic cells and intensified release of proinflammatory cytokines IFN-gamma, IL-12, and granulocyte/macrophage-colony stimulating factor from T cells of successfully vaccinated CEA-transgenic C57BL/6J mice. Increased T-cell activation mediated by boosts with KS1/4-IL2 fusion protein after tumor cell challenge was further indicated by expanded expression of T-cell activation markers CD25, CD28, CD69, and LFA-1. The application of such CEA-based DNA vaccines and its further improved versions may ultimately prove useful in combination therapies directed against human carcinomas expressing CEA self-antigens.

The level of MHC class I expression on murine adenocarcinoma can change the antitumor effector mechanism of immunocytokine therapy

The huKS1/4-IL2 fusion protein, directed against the human epithelial cell adhesion molecule (huEpCAM) has been shown to induce a strong CD8+ T-cell-dependent, natural killer (NK) cell-independent, antitumor response in mice bearing the huEp-CAM-transfected CT26 colon cancer CT26-EpCAM. Here we investigate the effectiveness of huKS1/4-IL2 against CT26-Ep21.6, a subclone of CT26-EpCAM, expressing low levels of MHC class I. In vitro antibody-dependent cellular cytotoxicity (ADCC) assays in the presence of huKS1/4-IL2 demonstrate that murine NK cells from spleen and blood can kill CT26-Ep21.6 significantly better than they kill CT26-EpCAM. NK-mediated ADCC of CT26-EpCAM can be enhanced by blocking the murine NK cell-inhibitory receptor, Ly-49C. A potent in vivo antitumor effect was observed when BALB/c mice bearing experimental metastases of CT26-Ep21.6 were treated with huKS1/4-IL2. The depletion of NK cells during huKS1/4-IL2 treatment significantly reduced the antitumor effect against CT26-Ep21.6. Together our in vitro and in vivo data in the huEp-CAM-transfected CT26 models indicate that the amount of MHC class I expressed on the tumor target cell plays a critical role in the in vivo antitumor mechanism of huKS1/4-IL2 immunotherapy. A low MHC class I level favors NK cells as effectors, whereas a high level of MHC class I favors T cells as effectors. Given the heterogeneity of MHC class I expression seen in human tumors and the prevailing T-cell suppression in many cancer patients, the observation that huKS1/4-IL2 has the potential to effectively activate an NK cell-based antitumor response may be of potential clinical relevance.

Tyrosine hydroxylase-based DNA-vaccination is effective against murine neuroblastoma

BACKGROUND

The disruption of self-tolerance against neuroblastoma is the ultimate goal of an effective DNA-vaccine.

PROCEDURE

Here we demonstrate the induction of a protective immunity against syngeneic murine NXS2 neuroblastoma in A/J mice, following vaccination with tyrosine hydroxylase (TH) derived antigens. Oral gene delivery was accomplished using an attenuated strain of Salmonella typhimurium as a carrier harboring vectors encoding for mTH antigens.

RESULTS

Vaccination was effective in protecting animals from a lethal challenge with wild-type NXS2 tumor cells.

CONCLUSIONS

These results provide the first evidence of the TH self antigen being recognized by T-cells and demonstrate that a TH-based DNA vaccine is a potentially useful immunotherapeutic strategy for neuroblastoma.

Tyrosine hydroxylase-based DNA-vaccination is effective against murine neuroblastoma

BACKGROUND

The disruption of self-tolerance against neuroblastoma is the ultimate goal of an effective DNA-vaccine.

PROCEDURE

Here we demonstrate the induction of a protective immunity against syngeneic murine NXS2 neuroblastoma in A/J mice, following vaccination with tyrosine hydroxylase (TH) derived antigens. Oral gene delivery was accomplished using an attenuated strain of Salmonella typhimurium as a carrier harboring vectors encoding for mTH antigens.

RESULTS

Vaccination was effective in protecting animals from a lethal challenge with wild-type NXS2 tumor cells.

CONCLUSIONS

These results provide the first evidence of the TH self antigen being recognized by T-cells and demonstrate that a TH-based DNA vaccine is a potentially useful immunotherapeutic strategy for neuroblastoma.

Brownian Coagulation of Fractal Agglomerates: Analytical Solution Using the Log-Normal Size Distribution Assumption

An analytical solution to Brownian coagulation of fractal agglomerates in the continuum regime that provides time evolution of the particle size distribution is presented. The theoretical analysis is based on representation of the size distribution of coagulating agglomerates with a time-dependent log-normal size distribution function and employs the method of moments together with suitable simplifications. The results are found in the form that extends the spherical particle solution previously obtained by K. W. Lee (J. Colloid Interface Sci. 92, 315-325 (1983)). The results show that the mass fractal dimension has a significant effect on the size distribution evolution during coagulation. When the obtained solution was compared with numerical results, good agreement was found. The self-preserving size distribution of nonspherical agglomerates is discussed. Copyright 2000 Academic Press.

Melanoma immunotherapy by targeted IL-2 depends on CD4(+) T-cell help mediated by CD40/CD40L interaction

The induction of tumor-protective immunity against malignancies remains a major challenge in cancer immunotherapy. A novel, humanized anti-ganglioside-GD(2)-IL-2 immunocytokine (hu14.18-IL-2) induced CD8(+) T cells to eradicate established pulmonary metastases of B78-D14 murine melanoma, in a process that required help by CD4(+) T cells and was mediated by the CD40/CD40 ligand (CD40L) interaction. The anti-tumor effect was diminished in mice deficient in CD4(+) T-cells. Three lines of evidence show that CD4(+) T-cell help was mediated by CD40/CD40L interaction but not by endogenous IL-2 production. First, the hu14.18-IL-2-induced anti-tumor response is partially abrogated in C57BL/6J CD40L knockout (KO) mice in contrast to C57BL/6J IL-2 KO animals, in which the immunocytokine was completely effective. Second, partial abrogation of the anti-tumor effect is induced with anti-CD40L antibodies to the same extent as with CD4(+) T-cell depletion. Third, a complete anti-tumor response induced by hu14.18-IL-2 can be reconstituted in C57BL/6J CD40L KO mice by simultaneous stimulation with an anti-CD40 mAb. These results suggest that help provided by CD4(+) T cells via CD40/CD40L interactions in our tumor model is crucial for effective immunotherapy with an IL-2 immunocytokine.

An autologous oral DNA vaccine protects against murine melanoma

We demonstrated that peripheral T cell tolerance toward murine melanoma self-antigens gp100 and TRP-2 can be broken by an autologous oral DNA vaccine containing the murine ubiquitin gene fused to minigenes encoding peptide epitopes gp100(25-33) and TRP-2(181-188). These epitopes contain dominant anchor residues for MHC class I antigen alleles H-2D(b) and H-2K(b), respectively. The DNA vaccine was delivered by oral gavage by using an attenuated strain of Salmonella typhimurium as carrier. Tumor-protective immunity was mediated by MHC class I antigen-restricted CD8(+) T cells that secreted T(H)1 cytokine IFN-gamma and induced tumor rejection and growth suppression after a lethal challenge with B16G3. 26 murine melanoma cells. Importantly, the protective immunity induced by this autologous DNA vaccine against murine melanoma cells was at least equal to that achieved through xenoimmunization with the human gp100(25-33) peptide, which differs in its three NH(2)-terminal amino acid residues from its murine counterpart and was previously reported to be clearly superior to an autologous vaccine in inducing protective immunity. The presence of ubiquitin upstream of the minigene proved to be essential for achieving this tumor-protective immunity, suggesting that effective antigen processing and presentation may make it possible to break peripheral T cell tolerance to a self-antigen. This vaccine design might prove useful for future rational designs of other recombinant DNA vaccines targeting tissue differentiation antigens expressed by tumors.

What to do with targeted IL-2

A common strategy in immunotherapy of cancer is the induction of an increased immunogenicity of syngeneic malignancies. A novel approach to achieve this goal is the targeting of cytokines into the tumor microenvironment with antibody-cytokine fusion proteins, called immunocytokines. This report summarizes therapeutic efficacy and immune mechanisms involved in targeting IL-2 to syngeneic tumors and describes their extended use as a synergistic treatment modality for cancer vaccines and antiangiogenesis. Treatment of established melanoma and colon carcinoma metastases with IL-2 immunocytokines resulted in eradication of disease, followed by a vaccination effect protecting mice from lethal challenges with wild-type tumor cells. In a syngeneic neuroblastoma model, targeted IL-2 elicited effective antitumor responses mediated by NK cells in the absence of a T-cell memory. Interestingly, targeted IL-2 was effective in amplification of memory immune responses previously induced by cancer vaccines. Furthermore, a synergistic effect achieved by combining targeted IL-2-immunotherapy with an antiangiogenic inhibitor of integrin alpha(v)beta(3) extends the potential of this immunotherapeutic strategy in combination with antiangiogenesis as demonstrated in three syngeneic tumor models. Based on these findings, targeted IL-2 may provide an effective tool for the adjuvant treatment of cancer either applied as a single strategy or in combination with cancer vaccines and antiangiogenic strategies.

T cell memory against colon carcinoma is long-lived in the absence of antigen

Eradication of established colon carcinoma metastases is a major goal for adjuvant immunotherapy of this disease. This was accomplished in a murine model by targeting IL-2 to the tumor microenvironment with a recombinant Ab-IL-2 fusion protein (huKS1/4-IL-2). The generation of a long-lived protective immunity was demonstrated by a 10- to 14-fold increase in CTL precursor (pCTL) frequency and induction of genes encoding Th1 cytokines, followed by the generation of tumor-specific CD8+ T effector cells, some of which differentiated into long-lived T memory cells. The frequency of pCTL correlated with enhanced immune protection against tumor cell challenge, and long-lived T cell memory was maintained in syngeneic SCID mice in the absence of tumor Ag. Tumor cell challenge of these SCID mice, concomitant with a boost of two noncurative doses of huKS1/4-IL-2 fusion protein, resulted in the generation of primed CD8+ T effector cells with concurrent release of Th1 cytokines. These events culminated in the complete rejection of the tumor cell challenge and prevention of pulmonary metastases. Taken together, the data suggest that T cell memory against colon carcinoma can be maintained in the absence of Ag.

Tumor-targeted IL-2 amplifies T cell-mediated immune response induced by gene therapy with single-chain IL-12

Induction, maintenance, and amplification of tumor-protective immunity after cytokine gene therapy is essential for the clinical success of immunotherapeutic approaches. We investigated whether this could be achieved by single-chain IL-12 (scIL-12) gene therapy followed by tumor-targeted IL-2 using a fusion protein containing a tumor-specific recombinant anti-ganglioside GD(2) antibody and IL-2 (ch14.18-IL-2) in a poorly immunogenic murine neuroblastoma model. Herein, we demonstrate the absence of liver and bone marrow metastases after a lethal challenge with NXS2 wild-type cells only in mice (five of six animals) vaccinated with scIL-12-producing NXS2 cells and given a booster injection of low-dose ch14.18-IL-2 fusion protein. This tumor-protective immunity was effective 3 months after initial vaccination, in contrast to control animals treated with a nonspecific fusion protein or an equivalent mixture of antibody and IL-2. Only vaccinated mice receiving the tumor-specific ch14.18-IL-2 fusion protein revealed a reactivation of CD8(+) T cells and subsequent MHC class I-restricted tumor target cell lysis in vitro. The sequential increase in the usage of TCR chains Vbeta11 and -13 in mouse CD8(+) T cells after vaccination and amplification with ch14.18-IL-2 suggests that the initial polyclonal CD8(+) T cell response is effectively boosted by targeted IL-2. In conclusion, we demonstrate that a successful boost of a partially protective memory T cell immune response that is induced by scIL-12 gene therapy could be generated by tumor-specific targeting of IL-2 with a ch14.18-IL-2 fusion protein. This approach could increase success rates of clinical cancer vaccine trials.

Synergy between an antiangiogenic integrin alphav antagonist and an antibody-cytokine fusion protein eradicates spontaneous tumor metastases

The suppression and eradication of primary tumors and distant metastases is a major goal of alternative treatment strategies for cancer, such as inhibition of angiogenesis and targeted immunotherapy. We report here a synergy between two novel monotherapies directed against vascular and tumor compartments, respectively, a tumor vasculature-specific antiangiogenic integrin alphav antagonist and tumor-specific antibody-interleukin 2 (IL-2) fusion proteins. Simultaneous and sequential combination of these monotherapies effectively eradicated spontaneous liver metastases in a poorly immunogenic syngeneic model of neuroblastoma. This was in contrast to controls subjected to monotherapies with either an antiangiogenic integrin alphav antagonist or antibody-IL-2 fusion proteins, which were only partially effective at the dose levels applied. Furthermore, simultaneous treatments with the integrin alphav antagonist and tumor-specific antibody-IL-2 fusion proteins induced dramatic primary tumor regressions in three syngeneic murine tumor models, i.e., melanoma, colon carcinoma, and neuroblastoma. However, each agent used as monotherapy induced only a delay in tumor growth. A mechanism for this synergism was suggested because the antitumor response was accompanied by a simultaneous 50% reduction in tumor vessel density and a 5-fold increase in inflammatory cells in the tumor microenvironment. Subsequently, tumor necrosis was demonstrated only in animals receiving the combination therapy, but not when each agent was applied as monotherapy. The results suggest that these synergistic treatment modalities may provide a novel and effective tool for future therapies of metastatic cancer.