Complete genome sequence of Pediococcus acidilactici A40, a bacterium with biocontrol and plant growth-promoting properties

We report the complete genome assembly of Pediococcus acidilactici A40, a bacterium with biocontrol and plant growth-promoting properties, obtained from Colombia.

Functional and Phylogenetic Characterization of Bacteria in Bovine Rumen Using Fractionation of Ruminal Fluid

Cattle productivity depends on our ability to fully understand and manipulate the fermentation process of plant material that occurs in the bovine rumen, which ultimately leads to the improvement of animal health and increased productivity with a reduction in environmental impact. An essential step in this direction is the phylogenetic and functional characterization of the microbial species composing the ruminal microbiota. To address this challenge, we separated a ruminal fluid sample by size and density using a sucrose density gradient. We used the full sample and the smallest fraction (5%), allowing the enrichment of bacteria, to assemble metagenome-assembled genomes (MAGs). We obtained a total of 16 bacterial genomes, 15 of these enriched in the smallest fraction of the gradient. According to the recently proposed Genome Taxonomy Database (GTDB) taxonomy, these MAGs belong to Bacteroidota, Firmicutes_A, Firmicutes, Proteobacteria, and Spirochaetota phyla. Fifteen MAGs were novel at the species level and four at the genus level. The functional characterization of these MAGs suggests differences from what is currently known from the genomic potential of well-characterized members from this complex environment. Species of the phyla Bacteroidota and Spirochaetota show the potential for hydrolysis of complex polysaccharides in the plant cell wall and toward the production of B-complex vitamins and protein degradation in the rumen. Conversely, the MAGs belonging to Firmicutes and Alphaproteobacteria showed a reduction in several metabolic pathways; however, they have genes for lactate fermentation and the presence of hydrolases and esterases related to chitin degradation. Our results demonstrate that the separation of the rumen microbial community by size and density reduced the complexity of the ruminal fluid sample and enriched some poorly characterized ruminal bacteria allowing exploration of their genomic potential and their functional role in the rumen ecosystem.

Disentangling the Complexity of the Rumen Microbial Diversity Through Fractionation Using a Sucrose Density Gradient

The ruminal microbial community is an important element in health, nutrition, livestock productivity, and climate impact. Despite the historic and current efforts to characterize this microbial diversity, many of its members remain unidentified, making it challenging to associate microbial groups with functions. Here we present a low-cost methodology for rumen sample treatment that separates the microbial community based on cell size, allowing for the identification of subtle compositional changes. In brief, the sample is centrifuged through a series of sucrose density gradients, and cells migrate to their corresponding density fraction. From each fraction, DNA is extracted and 16S rRNA gene amplicons are sequenced. We tested our methodology on four animals under two different conditions, fasting, and post-feeding. Each fraction was examined by confocal microscopy showing that the same sucrose fraction consistently separated similar cell-sized microorganisms independent of the animal or treatment. Microbial composition analysis using metabarcoding showed that our methodology detected low abundance bacterial families and population changes between fasting and post-feeding treatments that could not be observed by bulk DNA analysis. In conclusion, the sucrose-based method is a powerful low-cost approximation to untwine, enrich, and potentially isolate uncharacterized members of the ruminal microbiome.

Abstract 806: TGFBR1*6A enhances breast cancer susceptibility and promote cell cycle transition

Background: TGFBR1*6A is a polymorphic variant of the Transforming Growth Factor Beta receptor 1 (TGFBR1) that has three GCG synonymous deletions in its signal peptide. It is a low penetrance breast cancer susceptibility allele (OR, 1.15; 95% CI, 1.01 to 1.31) postulated to enhance tumor formation. In this study, a novel breast cancer mouse model carrying humanized TGFBR1*6A (hTGFBR1*6A) knock-in was used to investigate TGFBR1*6A influence on breast cancer formation, and dissect its molecular pathogenicity.

Methods: Humanized mouse models of the two most common TGFBR1*6A genotypes - homozygous TGFBR1*6A/6A and heterozygous TGFBR1*9A/6A, and wild-type TGFBR1 were created by replacing murine Tgfbr1 exon 1 with human TGFBR1*6A or TGFBR1 exon 1. The three genotypes were bred with MMTV.Neu mice to study breast cancer development. Between 29-35 nulliparous females from each genotype were monitored for tumor formation (≥1 tumor), multiple tumor formation (≥2 tumors) and survival. Tumor cells were isolated from the hTGFBR1 and hTGFBR1*6A mice and validated for similar Neu protein expression. They were assessed for TGF-β/FoxO1 signaling as it relates to cell cycle progression and proliferation.

Results: After 548 days, the mice harboring hTGFBR1*6A developed significantly more tumors (p=0.003 for one/more tumors, and p=0.0009 for two/more tumors) than wild-type mice. About 70% hTGFBR1*6A/6A and 28.6% hTGFBR1*9A/6A variants compared to 18.5% hTGFBR1 wild-type mice developed two (2) or more tumors. The hTGFBR1*6A mice also had shorter survival when compared with the wild-type mice (Log rank X2=7.77, p=0.02). The hTGFBR1*6A/6A and hTGFBR1*9A/6A mice survived for 178-210 and 208-282 days respectively compared to 198-342 days among the wild-type. The isolated hTGFBR1*6A tumor cells formed three (3) times more colonies, and exhibited higher growth rate and G1/S cell cycle transition than wild-type tumor cells. Interestingly, the hTGFBR1*6A cells were less sensitive to TGF-β anti-proliferative effects despite showing marked increase in TGF-β/SMAD signaling. Analyses of the TGF-β/FoxO1 growth inhibition pathway showed decreased FoxO1, p21 and p27 gene and protein expression, which was not increased significantly by TGF-β treatment. This suggests that TGFBR1*6A constitutively inhibits the TGF-β/FoxO1 cell cycle tumor suppressor arm.

Conclusions: Altogether, this study provides new evidence in support of TGFBR1*6A as a breast cancer susceptibility allele. It also identifies deregulation of TGF-β/FoxO1 cell cycle inhibition as a potential mechanism underlying its increased cellular proliferation.

Citation Format: Kojo Agyemang, Michael Pennison, Minghui Wang, Allan Johansen, Hugo Jimenez, Carl Blackman, Ravi Singh, Ralph D'Agostino, Paul Grippo, Antonio Di Cristofano, Boris Pasche. TGFBR1*6A enhances breast cancer susceptibility and promote cell cycle transition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 806.

Toll-like receptor-4 deficiency inhibits ultraviolet radiation-induced tumor development by modulation of immune and inflammatory responses

Ultraviolet (UV) B irradiation of the skin induces acute inflammation, as characterized by erythema, edema, and immunosuppression, and is subsequently linked to the progression of skin cancer. Toll-like receptor 4 (TLR4), a component of innate immunity, has been shown to play an important role in cancer. To elucidate the role of TLR4 in UVB-induced tumor development, TLR4-proficient (C3H/HeN) and TLR4-deficient (C3H/HeJ) mice were exposed to multiple doses of UVB radiation (200 mJ/cm² ) for 40 weeks. Photocarcinogenesis was retarded in terms of tumor incidence, and tumor latency, in mice deficient in TLR4 compared with TLR4-proficient mice, whereas significantly greater numbers of tumors occurred in TLR4-proficient mice. There was significant upregulation of inflammatory markers like COX-2, PGE₂ , S100A8, and S100A9 in the skin of TLR4-proficient mice than the skin of TLR4-deficient mice. Furthermore, we found that TLR4-proficient mice had a significantly higher number of Gr1+CD11b+ myeloid cells CD4+CD25+ regulatory T-cells than TLR4-deficient mice. Furthermore, the levels of interferon (IFN)-γ cytokine was increased and the levels of interleukin (IL)-4, IL-10, and IL-17 cytokines were decreased in serum, skin, and tumor lysates of TLR4-deficient mice in comparison with samples from TLR4-proficient mice. Together, our data indicate that TLR4-mediated inflammation may cause suppression of antitumor responses and trigger the development of UVB-induced skin cancers. Thus, strategies to inhibit TLR4-mediated immune suppression may allow us to develop preventive and therapeutic approaches for the management of UVB-induced cutaneous tumors.

Tumour-specific amplitude-modulated radiofrequency electromagnetic fields induce differentiation of hepatocellular carcinoma via targeting Cav3.2 T-type voltage-gated calcium channels and Ca2+ influx

BACKGROUND

Administration of amplitude modulated 27·12 MHz radiofrequency electromagnetic fields (AM RF EMF) by means of a spoon-shaped applicator placed on the patient's tongue is a newly approved treatment for advanced hepatocellular carcinoma (HCC). The mechanism of action of tumour-specific AM RF EMF is largely unknown.

METHODS

Whole body and organ-specific human dosimetry analyses were performed. Mice carrying human HCC xenografts were exposed to AM RF EMF using a small animal AM RF EMF exposure system replicating human dosimetry and exposure time. We performed histological analysis of tumours following exposure to AM RF EMF. Using an agnostic genomic approach, we characterized the mechanism of action of AM RF EMF.

FINDINGS

Intrabuccal administration results in systemic delivery of athermal AM RF EMF from head to toe at levels lower than those generated by cell phones held close to the body. Tumour shrinkage results from differentiation of HCC cells into quiescent cells with spindle morphology. AM RF EMF targeted antiproliferative effects and cancer stem cell inhibiting effects are mediated by Ca2+ influx through Cav3·2 T-type voltage-gated calcium channels (CACNA1H) resulting in increased intracellular calcium concentration within HCC cells only.

INTERPRETATION

Intrabuccally-administered AM RF EMF is a systemic therapy that selectively block the growth of HCC cells. AM RF EMF pronounced inhibitory effects on cancer stem cells may explain the exceptionally long responses observed in several patients with advanced HCC. FUND: Research reported in this publication was supported by the National Cancer Institute's Cancer Centre Support Grant award number P30CA012197 issued to the Wake Forest Baptist Comprehensive Cancer Centre (BP) and by funds from the Charles L. Spurr Professorship Fund (BP). DWG is supported by R01 AA016852 and P50 AA026117.

Ca2+ and CACNA1H mediate targeted suppression of breast cancer brain metastasis by AM RF EMF

BACKGROUND

Brain metastases are a major cause of death in patients with metastatic breast cancer. While surgical resection and radiation therapy are effective treatment modalities, the majority of patients will succumb from disease progression. We have developed a novel therapy for brain metastases that delivers athermal radiofrequency electromagnetic fields that are amplitude-modulated at breast cancer specific frequencies (BCF).

METHODS

27.12 MHz amplitude-modulated BCF were administered to a patient with a breast cancer brain metastasis by placing a spoon-shaped antenna on the anterior part of the tongue for three one-hour treatments every day. In preclinical models, a BCF dose, equivalent to that delivered to the patient's brain, was administered to animals implanted with either brain metastasis patient derived xenografts (PDXs) or brain-tropic cell lines. We also examined the efficacy of combining radiation therapy with BCF treatment. Additionally, the mechanistic underpinnings associated with cancer inhibition was identified using an agnostic approach.

FINDINGS

Animal studies demonstrated a significant decrease in growth and metastases of brain-tropic cell lines. Moreover, BCF treatment of PDXs established from patients with brain metastases showed strong suppression of their growth ability. Importantly, BCF treatment led to significant and durable regression of brain metastasis of a patient with triple negative breast cancer. The tumour inhibitory effect was mediated by Ca²⁺ influx in cancer cells through CACNA1H T-type voltage-gated calcium channels, which, acting as the cellular antenna for BCF, activated CAMKII/p38 MAPK signalling and inhibited cancer stem cells through suppression of β-catenin/HMGA2 signalling. Furthermore, BCF treatment downregulated exosomal miR-1246 level, which in turn decreased angiogenesis in brain environment. Therefore, targeted growth inhibition of breast cancer metastases was achieved through CACNA1H.

INTERPRETATION

We demonstrate that BCF, as a single agent or in combination with radiation, is a novel treatment approach to the treatment of brain metastases. This paradigm shifting modality warrants further clinical trials for this unmet medical need.

Abstract P5-07-16: Role of collagen X in enhancing the metastatic potential of breast cancer cells using a MDA-MB-231 cell line model

Breast cancer is the second highest cause of cancer related deaths for women in developed countries. Breast cancer patients with distant metastasis at the time of diagnosis have an estimated 5-year relative survival rate of 26% as compared to a 99% survival rate of patients who have localized tumors. Evidence suggests that collagens play a role in enhancing the metastatic capability of breast cancer cells. Short chain collagen, collagen X, is encoded by the collagen type x alpha 1 chain (COL10A1) gene and is normally expressed exclusively by hypertrophic chondrocytes during endochondral ossification. Recently, COL10A1 gene expression has been found to be overexpressed in various tumor types, including breast tumors. It is hypothesized that an increase in COL10A1 expression may play a role in breast cancer metastasis. The goal of our project was to evaluate the role of collagen X in breast cancer metastasis using the MDA-MB-231 breast cancer cell line. Stable cell lines were generated to express either GFP only (MDA-VEC) or GFP tagged COL10A1 (MDA-COL). GFP and COL10A1 transcript and protein levels were examined to confirm overexpression of collagen X and transwell assays were used to determine changes in the invasive capability of the cells. Cells overexpressing collagen X demonstrated a higher rate of invasion suggesting that collagen X may play a role in enhancing the metastatic potential of breast cancer cells. Understanding the role collagen X plays in breast cancer metastasis may provide a mechanism for developing diagnostic and prognostic strategies for identifying patients whose breast cancer is more prone to metastasize.

Citation Format: McKiernan K, Jimenez H, McEachern M, Hubbard J, O'Connell M. Role of collagen X in enhancing the metastatic potential of breast cancer cells using a MDA-MB-231 cell line model [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-07-16.

Amplitude-modulated radiofrequency electromagnetic fields target hepatocellular carcinoma stem cells through activation of Cav 3.2 T-type calcium channels

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Background: Amplitude-modulated 27.12 MHz radiofrequency electromagnetic fields (AM RF EMF) delivered via a spoon-shaped antenna placed on the patient’s tongue result in shrinkage of the primary and metastatic tumors in patients with advanced hepatocellular carcinoma (HCC). (Costa FP, et al. Br J Cancer. 2011;105:640-648.) The mechanism by which AM RF EMF have direct antiproliferative effect and disruption of the mitotic spindle on cancer cells is largely unknown. (Zimmerman JW, et al. Br J Cancer. 2012;106:307-313.) Methods: We assessed the Specific Absorption Rate (SAR) level and distribution inside the human body. In vitro experiments with HCC cells were performed as previously described (Zimmerman). Immunodeficient mice were subcutaneously implanted with Huh-7 HCC cells or patient-derived xenografts (PDX). Mice were exposed to HCC-specific AM RF EMF using systems replicating human exposure levels and treatment duration. Tumor samples were examined for EMT and cell cycle markers. Results: Intrabuccal delivery results in whole-body absorption of AM RF EMF. Proliferation of hepatitis B positive and negative cell lines as well as HCC cancer stem cells (CSCs) are blocked by AM RF EMF through Cav 3.2 T-type voltage gated calcium channels (VGCC). Proliferation of HCC is inhibited in vivo and tumor shrinkage occurs by dedifferentiation of HCC cells into quiescent myofibroblasts while the growth of intestinal and blood marrow cells is unaltered. Conclusions: Whole-body SAR ranges from 0.2 to 1 mW/kg and is significantly below the international safety limits for human exposure. Intrabucally-administered AM RF EMF is a novel targeted therapy for systemic treatment of advanced HCC with minimal off target effects. Inhibition of HCC CSCs may explain the extremely long term survival (>5 years) of several patients with advanced HCC.

Use of non-ionizing electromagnetic fields for the treatment of cancer

Cancer treatment and treatment options are quite limited in circumstances such as when the tumor is inoperable, in brain cancers when the drugs cannot penetrate the blood-brain-barrier, or when there is no tumor-specific target for generation of effective therapeutic antibodies. Despite the fact that electromagnetic fields (EMF) in medicine have been used for therapeutic or diagnostic purposes, the use of non-ionizing EMF for cancer treatment is a new emerging concept. Here we summarize the history of EMF from the 1890's to the novel and new innovative methods that target and treat cancer by non-ionizing radiation.

Pathogenic tau species drive a psychosis-like phenotype in a mouse model of Alzheimer's disease

Psychotic Alzheimer's disease (AD+P) is a rapidly progressive variant of AD associated with an increased burden of frontal tau pathology that affects up to 50% of those with AD, and is observed more commonly in females. To date, there are no safe and effective medication interventions with an indication for treatment in this condition, and there has been only very limited exploration of potential animal models for pre-clinical drug development. Pathogenic tau is over represented in the frontal cortex in AD+P, especially in females. In order to develop a candidate animal model of AD+P, we employed a tau mouse model with a heavy burden of frontal tau pathology, the rTg(tauP301L)4510 mouse, hereafter termed rTg4510. We explored deficits of prepulse inhibition of acoustic startle (PPI), a model of psychosis in rodents, and the correlation between pathogenic phospho-tau species associated with AD+P and PPI deficits in female mice. We found that female rTg4510 mice exhibit increasing PPI deficits relative to littermate controls from 4.5 to 5.5 months of age, and that these deficits are driven by insoluble fractions of the phospho-tau species pSer396/404, pSer202, and pThr231 found to be associated with human AD+P. This preliminary data suggests the utility of the rTg4510 mouse as a candidate disease model of human female AD+P. Further work expanded to include both genders and other behavioral outcome measures relevant to AD+P is necessary.

Targeted treatment of cancer with radiofrequency electromagnetic fields amplitude-modulated at tumor-specific frequencies

In the past century, there have been many attempts to treat cancer with low levels of electric and magnetic fields. We have developed noninvasive biofeedback examination devices and techniques and discovered that patients with the same tumor type exhibit biofeedback responses to the same, precise frequencies. Intrabuccal administration of 27.12 MHz radiofrequency (RF) electromagnetic fields (EMF), which are amplitude-modulated at tumor-specific frequencies, results in long-term objective responses in patients with cancer and is not associated with any significant adverse effects. Intrabuccal administration allows for therapeutic delivery of very low and safe levels of EMF throughout the body as exemplified by responses observed in the femur, liver, adrenal glands, and lungs. In vitro studies have demonstrated that tumor-specific frequencies identified in patients with various forms of cancer are capable of blocking the growth of tumor cells in a tissue- and tumor-specific fashion. Current experimental evidence suggests that tumor-specific modulation frequencies regulate the expression of genes involved in migration and invasion and disrupt the mitotic spindle. This novel targeted treatment approach is emerging as an appealing therapeutic option for patients with advanced cancer given its excellent tolerability. Dissection of the molecular mechanisms accounting for the anti-cancer effects of tumor-specific modulation frequencies is likely to lead to the discovery of novel pathways in cancer.

Prevention and treatment of cancer with aspirin: where do we stand?

Aspirin is arguably the synthesized drug that has been used most commonly in human history. Aspirin was originally developed and marketed for the treatment of inflammatory disorders at the end of the 19th century, but its mechanism of action remained unknown until the second half of the 20th century. Since the latter part of the 20th century aspirin also has been used for the primary and secondary prevention of cardiovascular diseases given its anti-thrombotic properties. An association between intake of aspirin and decreased cancer risk was identified in the past decades. Whether aspirin can be used as an anticancer agent in patients with a diagnosis of cancer was unknown until recently. Recent studies suggest that aspirin might provide therapeutic benefit in the adjuvant treatment of certain forms of cancer. This review provides a critical update on this topic, which has potential implications for oncologists and their patients.

TGFBR1 and cancer susceptibility

Transforming growth factor beta (TGF-β) is a potent inhibitor of cell growth. TGFBR1 6A is a polymorphism consisting of a 9-base pair in-frame deletion within exon 1 of the type I TGF-β receptor (TGFBR1), which results in a receptor with decreased TGF-β signaling capability. The discovery of an association between TGFBR1*6A and cancer susceptibility led to the hypothesis that hypomorphic variants of the TGF-β signaling pathway may predispose to the development of cancer. This hypothesis was tested in vivo with the development of a mouse model of Tgfbr1 haploinsufficiency. Tgfbr1 (+/-) mice developed twice as many intestinal tumors as Tgfbr1 (+/+). Tgfbr1 haploinsufficiency was also associated with early onset adenocarcinoma and increased tumor cell proliferation. A case control study identified two haplotypes associated with constitutively decreased TGFBR1 and substantially increased colorectal cancer risk indicating that TGFBR1 may act as a potent modifier of cancer risk.

Low levels of radiofrequency electromagnetic fields and cancer cell proliferation in vivo

e15049

Background: The incidence of hepatocellular carcinoma (HCC) is increasing but five-year survival remains dismal. Intrabuccal administration of amplitude-modulated radiofrequency electromagnetic fields (RF EMF) is a novel, non-invasive treatment modality resulting in whole body absorption of very low levels of RF EMF. Recent studies show that this approach elicits radiological responses in patients with HCC and breast cancer (J Exp Clin Cancer Res, 2009, 28:51; Br J Cancer, 2011, 105:640). Using an in vitro exposure system replicating the levels of exposure achieved in humans, we have shown that HCC cells and breast cancer cells are growth inhibited by HCC-specific and breast cancer-specific frequencies, respectively. Additionally, RF EMF exposure causes modulation of gene expression and disruption of the mitotic spindle (Br J Cancer 2012, 106:307). Methods: HCC cells were exposed to radiofrequency electromagnetic fields modulated at specific frequencies previously identified in HCC patients. MicroRNA arrays compared exposed and control groups of HCC cells. HCC cells were injected subcutaneously in NOD SCID mice. Following palpable tumor establishment, mice were exposed to HCC-specific RF EMF at a specific absorption rate of 0.4 W/kg and euthanized following excessive tumor burden. Results: We identified increased levels of miRNAs targeting proteins belonging to the PI3K pathway, specifically IP3/DAG signaling and intracellular calcium release, a pathway frequently disrupted in HCC and breast cancer. While HCC xenografts grew in control mice, we observed significant tumor shrinkage in mice exposed to HCC-specific modulation frequencies and residual xenograft tumor cells were infiltrated with fibrous tissue and showed significantly decreased proliferation and increased apoptosis. There was no evidence of altered cell proliferation or fibrosis in other organs. Conclusions: These findings are the first in vivo evidence of the efficacy of RF EMF in HCC and uncover a novel mechanism that targets cancer cell growth at specific modulation frequencies, by means of changes in PI3K signaling and release of intracellular calcium.

Abstract 5612: Cancer cell proliferation is inhibited by specific modulation frequencies

Purpose: Hepatocellular carcinoma (HCC) incidence in the US is dramatically increasing. Five-year survival remains 3-5%, demonstrating urgent need for additional therapies. Intrabuccal administration of amplitude modulated electromagnetic fields (RF EMF) is a novel, minimally invasive treatment modality which results in whole body absorption of very low levels of RF EMF. Clinical studies show that this treatment approach elicits therapeutic responses in patients with hepatocellular carcinoma and breast cancer. Using an in vitro exposure system replicating the levels of exposure achieved in humans, we have described a phenotype in HCC cells following RF EMF exposure that included proliferative inhibition, modulation of gene expression, and disruption of the mitotic spindle. This phenotype was specific for HCC cells exposed to HCC-specific RF EMF at exposure levels ranging from 0.03 to 0.4 W/kg.

Methods: HCC cells were exposed to 27.12 MHz electromagnetic fields modulated at specific frequencies from 400 Hz to 21 kHz, previously identified in HCC patients. MicroRNA arrays compared exposed and control groups of HCC cells, with microRNA validation followed by Western blot of target genes and proteins. HCC xenografts were injected subcutaneously in NOD SCID mice. Following palpable tumor establishment, mice were exposed to HCC-specific RF EMF at a specific absorption rate of 0.4 W/kg, euthanized following excessive tumor burden, and evaluated by immunohistochemistry.

Results: We identified increased levels of miRNAs targeting proteins belonging to the PI3K pathway, specifically IP3/DAG signaling and intracellular calcium release. This pathway is frequently disrupted in HCC and breast cancer, making it an excellent candidate for modulation by RF EMF; furthermore, downstream effects include: cell cycle progression, proliferation, inhibition of apoptosis, and cell migration. We observed tumor shrinkage in mice exposed to HCC-specific modulation frequencies and residual xenograft tumor cells were infiltrated with fibrous tissue and showed significantly decreased proliferation and increased apoptosis. There was no evidence of altered cell proliferation or fibrosis in other organs.

Conclusion: These findings are the first evidence of the efficacy and safety of RF EMF in HCC using a subcutaneous xenograft model and uncover a novel mechanism that controls cancer cell growth in vivo at specific modulation frequencies, possibly through modulation of PI3K signaling and downstream release of intracellular calcium.

Citation Format: Hugo Jimenez, Jacquelyn W. Zimmerman, Michael J. Pennison, Ivan Brezovich, Nengjun Yi, Celeste T. Yang, Ryne Ramaker, Devin Absher, Richard M. Myers, Niels Kuster, Frederico P. Costa, Alexandre Barbault, Boris Pasche. Cancer cell proliferation is inhibited by specific modulation frequencies. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5612. doi:10.1158/1538-7445.AM2013-5612

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

Caloric restriction responses can maintain immune responses during aging (47.14)

Age-related defects accumulate in both the innate and adaptive arms of immunity to generate a state of immune deficiency. Our laboratory has previously shown a decrease in immune responses in aged mice compared to younger mice in the context of OX40 costimulation. This loss of immunity during aging underscores the need for simple approaches to boost immunity in older individuals. We hypothesize that immune responses in the context of OX40 activation or blockade of CTLA-4 in older mice can be restored and/or maintained through caloric restriction (CR) or dietary supplementation with a CR mimetic. Two CR dietary regimens were used to determine if immunity in old immune-compromised mice could be restored and if immunity could be maintained during aging. In addition mice were fed diets that were formulated with resveratrol (100 ppm), a CR mimetic. Tumor immune responses and Ag-specific T cell responses in these mice were then assessed and compared to young mice and the appropriate dietary controls. Our results demonstrate that caloric restriction cannot restore immune function in old mice. However, CR or resveratrol dietary supplementation initiated at a young age can maintain both OX40-mediated anti-tumor immunity and T cell responses as these mice age. Thus, the induction of a caloric restriction response (via traditional CR or by a CR mimetic) appears to maintain immunological fitness and may increase the effectiveness of immune-based cancer therapies in older subjects.

Abstract 525: Toll-like receptor-4 mediated cutaneous immune responses augment ultraviolet radiation-induced DNA damage and tumor development

UV (ultraviolet) B induced DNA damage plays a critical role in development of skin cancer. The molecular basis for this biologic activity resides at least in part from the demonstrated ability of this form of radiant energy to damage DNA, predominantly in the form of cyclobutane pyrimidine dimers (CPD). The purpose of this study was to determine whether toll-like receptor-4 (TLR4) contributed to UV-induced DNA damage responses and cutaneous tumor development. TLR4 deficient and wild type (WT) mice were subjected to a local UVB induced DNA damage regimen consisting of 90 mJ/cm2 UVB radiation. Wild type mice exhibited significant (p<0.05) DNA damage in the form of cyclobutane pyrimidine dimers (CPD), whereas TLR4 deficient mice developed significantly fewer CPD (p<0.05) in their skin and bone marrow dendritic cells (BMDC). The expression of DNA repair gene XPA was significantly less (p<0.05) in skin and BMDC from WT mice than TLR4 deficient mice after UVB exposure. When cytokine levels were compared in these two strains after UVB exposure, BMDC from UV-irradiated TLR4 deficient mice produced significantly more IL-12 and IL-23 cytokines (p<0.05) than BMDC from WT mice. Furthermore, we found that Toll like receptor-4 (TLR4) promoted UVB induced tumor development. We observed that UVB induced skin carcinogenesis was retarded in terms of tumor incidence, and tumor latency, in mice deficient in TLR4 compared to WT mice, whereas significantly greater (p<0.05) numbers of tumors occurred in WT mice. Further, we found that tumor-bearing WT mice produced more IL-17 and IL-10 (p<0.05), whereas TLR4 deficient mice produced more IFN-γ (p<0.05). CD4+CD25+ regulatory T-cells from WT mice produced more IL-10 (p<0.05) than regulatory T-cells from TLR4 deficient mice. There was a significant increase (p<0.05) in Foxp3 expression in skin of WT mice than TLR4 deficient mice. Thus, strategies to inhibit TLR4 may allow us to develop immunopreventive and immunotherapeutic approaches for management of UVB induced cutaneous DNA damage and skin cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 525. doi:1538-7445.AM2012-525

Tualang honey protects keratinocytes from ultraviolet radiation-induced inflammation and DNA damage

Malaysian tualang honey possesses strong antioxidant and anti-inflammatory properties. Here, we evaluated the effect of tualang honey on early biomarkers of photocarcinogenesis employing PAM212 mouse keratinocyte cell line. Keratinocytes were treated with tualang honey (1.0%, v/v) before a single UVB (150 mJ cm(-2) ) irradiation. We found that the treatment of tualang honey inhibited UVB-induced DNA damage, and enhanced repair of UVB-mediated formation of cyclobutane pyrimidine dimers and 8-oxo-7,8-dihydro-2'-deoxyguanosine. Treatment of tualang honey inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in murine keratinocyte cell line. The treatment of tualang honey also inhibited UVB-induced inflammatory cytokines and inducible nitric oxide synthase protein expression. Furthermore, the treatment of tualang honey inhibited UVB-induced COX-2 expression and PGE2 production. Taken together, we provide evidence that the treatment of tualang honey to keratinocytes affords substantial protection from the adverse effects of UVB radiation via modulation in early biomarkers of photocarcinogenesis and provide suggestion for its photochemopreventive potential.

Fluorescamine as a terminating agent in solid phase peptide synthesis

Fluorescamine was shown to be an excellent terminating agent for blocking unreacted amino groups during solid phase peptide synthesis. A comparison of the termination efficiency of fluorescamine versus that of acetylation revealed that the former method gave superior products as assessed by peptide analysis, dansyl-amino end group determination and biological assay. In addition, fluorescamine terminated fragments were converted to non-fluorescent spirolactones during the deprotection stage. These spirolactones were stable to subsequent solid phase reaction conditions and were readily removed from the target peptide.

Clinical comparison of technetium-99m-teboroxime and thallium-201 utilizing a continuous SPECT imaging protocol

To examine the advantages of a 99mTc-labeled cardiac perfusion agent, teboroxime or SQ30,217 (Squibb Diagnostics), a prospective study was undertaken comparing it to 201Tl stress testing in 17 patients suspected or known of having coronary artery disease (CAD). All patients were studied utilizing a single-detector SPECT camera with a continuous acquisition imaging protocol. Testing was performed on a treadmill to comparable levels with both agents within a 2-wk period. Concordance between the two studies on a patient by patient basis was seen in 16/17 (94%) patients, and discordance was seen in 1/17 (6%) patients. Comparison of findings between 201Tl and 99mTc-teboroxime on a segment by segment basis showed concordance in 107/119 (90%) segments, and 12/119 (10%) were discordant. Both examinations independently detected an equal number of normal (77) and abnormal (42) segments. There was no significant difference between the two agents in classifying lesions as ischemic, although there were significant differences between thallium and teboroxime in classifying infarct and infarct/ischemia. Technetium-99m-teboroxime SPECT imaging is a clinically useful method for detecting CAD, with a major advantage being the shorter examination time per individual patient study. The mean total examination time for completion of the 99mTc-teboroxime study was 2.5 hr versus 4.0 hr for 201Tl.

Penetrating wounds of the back and flank: analysis of 77 cases

To determine the factors that allow early recognition of injuries to the intrathoracic and intra-abdominal organs in patients with penetrating wounds to the lower thorax and abdomen with site of entrance located in the back or flanks, we retrospectively analyzed the cases of 77 such patients. There were 65 stab wounds (85%) and 12 gunshot wounds (15%). The injuries were confined to the abdomen in 46 (60%); 39 were stab wounds and seven were gunshot wounds. The wounds were confined to the chest in 24 patients (31%) and involved both the chest and abdomen in seven cases (9%). Of the 53 abdominal wounds, 21 necessitated celiotomy; in 20 of them, an intra-abdominal organ was found injured, and one patient died (1.9%). Of the 24 injuries confined to the chest, only one patient required emergency thoracotomy due to massive hemorrhage; all 24 patients survived. All of the seven thoracoabdominal injuries, two produced by gunshot and five by stabbing, necessitated celiotomy. Most patients with gunshot wounds to the back and flanks require celiotomy, but a selective therapy can be safely used in patients with stab wounds. The rate of negative exploratory celiotomy was less than 5%; the mortality was 1.3%.

Clinical implications derived from the morphological classification of 89 patients with acute pancreatitis

A morphologic categorization of pancreatitis which can only be made at operation or at autopsy has prognostic and therapeutic implications. We reviewed 89 such cases and classified them as follows: 1) Edematous in 54 (60.7%). All patients underwent operation; five (9.2%) died. 2) Necrotizing in 20 (22.5%). Eighteen patients required operation. Seven (39%) patients died; two patients treated nonoperatively died. 3) Hemorrhagic in 15 (16.8%). Operation was performed in nine with five (55.5) deaths; six patients treated without operation died. These observations suggest that 50% of patients operated on for pancreatitis have the mild edematous form; most of them survive the operation. In the severe forms of pancreatitis with necrosis or hemorrhage of the pancreas, about 50% of patients die postoperatively. There were no survivors in those treated without operation, suggesting the usefulness of surgical treatment once pancreatic necrosis is suspected. However, the advisability of operation and the prognostic implications derived from the morphologic categorization of acute pancreatitis are applicable (only retrospectively) after the pancreas has been examined at operation.

Effects of various operations on the electrical activity of the human stomach recorded during the postoperative recovery period

This study attempts to characterize any changes occurring in the human gastric control electrical rhythm (CER), following a variety of gastric surgical procedures. Pairs of electrodes were implanted in selected specific sites on the stomachs of 57 patients undergoing either antrectomy and vagotomy, proximal gastric vagotomy (PGV), vagotomy and drainage, gastric resection without vagotomy, or fundoplication. Five patients undergoing nongastric operations served as controls. After operation recordings were obtained with differential preamplifiers, an oscilloscope, and a dual-channel tape recorder. An electrical signal compatible with a CER was found almost always in the distal body or antrum, regardless of whether vagotomy was performed. In contrast, a CER was found only occasionally in the fundus, and was never found following PGV. Although there was a difference in the frequency of occurrence of fundic CER in patients with and without vagotomy, it was not statistically significant (p = 0.0668). Patients with prolonged postoperative convalescence because of gastric atony were compared with patients with normal postoperative courses regarding the presence or absence of CER in the gastric antrum or fundus. A statistically significant relationship between abnormal gastric motility and absence of CER was not established.

Autocorrelation, cross correlation and coherence analyses of the electrical activity of the human stomach in the postoperative period

Electrical potentials generated by the stomach have been well categorized. They vary in amplitude, shape, frequency and time relationships and may be contaminated by electrical activity from other organs. In addition to visual observation, this investigation used methods of autocorrelation and cross correlation, spectral analysis and coherence determinations to refine and numerically characterize gastric electrical potentials. Bipolar Teflon coated electrode wires were brought out through the abdominal wall in six patients, four of whom underwent fundoplication, one of whom underwent cholecystectomy and one of whom underwent portacaval shunt. Recordings were obtained until the ninth postoperative day using differential preamplifiers, an oscilloscope and a dual channel tape recorder. Oscilloscope displays were photographed, and the outputs of the tape recorder were filtered in the analog mode. Similar recordings were also obtained postoperatively in a patient with gastric stasis, and a surface electrode was used to record the gastric electrical activity of a normal volunteer. The propagation time, electrical control activity frequencies and bioelectrical dependence or independence between the two measuring sites were clearly differentiated by these methods. This method offers a safe and feasible way of recording and analyzing the electrical activity of the human stomach in the postoperative period with statistically specified reliability. This is accomplished through temporarily implanted wires, and, potentially, from the surface of the body, even during electrical interference.

Evaluation and treatment of acute and chronic pancreatitis. A review of 380 cases

The cases of 380 patients with pancreatitis were analyzed retrospectively. There were 237 men (62%) and 143 women (38%). Etiologic factors included: alcoholism, 62%; biliary lithiasis, 16.6%; idiopathic, 12%; miscellaneous, 7%; and trauma, 2.4%. Acute pancreatitis occurred in 279 patients (73%); 189 (67%) were treated nonoperatively, 90 (33%) underwent operation; electively in 43 and urgently in 47. Postoperatively, one patient (2.3%) died in the elective group and 14 (30%) in the emergency group. Chronic pancreatitis occurred in 101 patients. Their pertinent findings were: alcoholism in 78%, biliary lithiasis in 8%, absence of abdominal pain in 15%, diabetes in 40%, and jaundice in 20%. Fifty patients were treated without operation; 43 were alcoholics, 17 of them died in the follow-up period. Fifty-one patients, 36 of them alcoholics, underwent a variety of operations, with three deaths (6%); 21 were improved after operation. It was concluded that 30% of patients with acute pancreatitis require operation, mainly to correct biliary lithiasis. Emergency operations dictated by relentless deterioration or uncertain diagnosis had a high operative mortality (30%), particularly in patients with necrotizing or hemorrhagic pancreatitis. Operative treatment for chronic pancreatitis was most effective when directed toward specific goals, including pseudocysts, obstructed pancreatic or common bile ducts. Operations done without specific anatomical objectives were often therapeutic failures.

Continuous tissue culture cell lines derived from chemically induced tumors of Japanese quail

Several continuous tissue culture cell lines were established from methylcholanthrene-induced fibrosarcomas of Japanese quail. The lines consist either of fibroblastic elements, round refractile cells or polygonal cells. They show transformed characteristics in agar colony formation and hexose uptake, and most are tumorigenic. Their cloning efficiency in plastic dishes is not increased over that of normal quail embryo fibroblasts. The quail tumor cell lines do not produce endogenous avian oncoviruses and fail to complement the Bryan high titer strain of Rous sarcoma virus; those tested lack the p27 protein of avian oncoviruses. Most of the cell lines are susceptible to subgroup A avian sarcoma viruses, but are relatively resistant to viruses of subgroups C, E and F as compared to normal quail embryo fibroblasts.