Novel RNA molecular bioengineering technology efficiently produces functional miRNA agents

Genome-derived microRNAs (miRNAs or miRs) govern posttranscriptional gene regulation and play important roles in various cellular processes and disease progression. While chemo-engineered miRNA mimics or biosimilars made in vitro are widely available and used, miRNA agents produced in vivo are emerging to closely recapitulate natural miRNA species for research. Our recent work has demonstrated the success of high-yield, in vivo production of recombinant miRNAs by using human tRNA (htRNA) fused precursor miRNA (pre-miR) carriers. In this study, we aim to compare the production of bioengineered RNA (BioRNA) molecules with glycyl versus leucyl htRNA fused hsa-pre-miR-34a carriers, namely, BioRNAGly and BioRNALeu, respectively, and perform the initial functional assessment. We designed, cloned, overexpressed, and purified a total of 48 new BioRNA/miRNAs, and overall expression levels, final yields, and purities were revealed to be comparable between BioRNAGly and BioRNALeu molecules. Meanwhile, the two versions of BioRNA/miRNAs showed similar activities to inhibit non-small cell lung cancer cell viability. Interestingly, functional analyses using model BioRNA/miR-7-5p demonstrated that BioRNAGly/miR-7-5p exhibited greater efficiency to regulate a known target gene expression (EGFR) than BioRNALeu/miR-7-5p, consistent with miR-7-5p levels released in cells. Moreover, BioRNAGly/miR-7-5p showed comparable or slightly greater activities to modulate MRP1 and VDAC1 expression, compared with miRCURY LNA miR-7-5p mimic. Computational modeling illustrated overall comparable 3D structures for exemplary BioRNA/miRNAs with noticeable differences in htRNA species and payload miRNAs. These findings support the utility of hybrid htRNA/hsa-pre-miR-34a as reliable carriers for RNA molecular bioengineering, and the resultant BioRNAs serve as functional biologic RNAs for research and development.

Molecular Engineering of Functional SiRNA Agents

Synthetic biology constitutes a scientific domain focused on intentional redesign of organisms to confer novel functionalities or create new products through strategic engineering of their genetic makeup. Leveraging the inherent capabilities of nature, one may address challenges across diverse sectors including medicine. Inspired by this concept, we have developed an innovative bioengineering platform, enabling high-yield and large-scale production of biological small interfering RNA (BioRNA/siRNA) agents via bacterial fermentation. Herein, we show that with the use of a new tRNA fused pre-miRNA carrier, we can produce various forms of BioRNA/siRNA agents within living host cells. We report a high-level overexpression of nine target BioRNA/siRNA molecules at 100% success rate, yielding 3-10 mg of BioRNA/siRNA per 0.25 L of bacterial culture with high purity (>98%) and low endotoxin (<5 EU/μg RNA). Furthermore, we demonstrate that three representative BioRNA/siRNAs against GFP, BCL2, and PD-L1 are biologically active and can specifically and efficiently silence their respective targets with the potential to effectively produce downstream antiproliferation effects by PD-L1-siRNA. With these promising results, we aim to advance the field of synthetic biology by offering a novel platform to bioengineer functional siRNA agents for research and drug development.

Inhibition of iRhom1 by CD44-targeting nanocarrier for improved cancer immunochemotherapy

The multifaceted chemo-immune resistance is the principal barrier to achieving cure in cancer patients. Identifying a target that is critically involved in chemo-immune-resistance represents an attractive strategy to improve cancer treatment. iRhom1 plays a role in cancer cell proliferation and its expression is negatively correlated with immune cell infiltration. Here we show that iRhom1 decreases chemotherapy sensitivity by regulating the MAPK14-HSP27 axis. In addition, iRhom1 inhibits the cytotoxic T-cell response by reducing the stability of ERAP1 protein and the ERAP1-mediated antigen processing and presentation. To facilitate the therapeutic translation of these findings, we develop a biodegradable nanocarrier that is effective in codelivery of iRhom pre-siRNA (pre-siiRhom) and chemotherapeutic drugs. This nanocarrier is effective in tumor targeting and penetration through both enhanced permeability and retention effect and CD44-mediated transcytosis in tumor endothelial cells as well as tumor cells. Inhibition of iRhom1 further facilitates tumor targeting and uptake through inhibition of CD44 cleavage. Co-delivery of pre-siiRhom and a chemotherapy agent leads to enhanced antitumor efficacy and activated tumor immune microenvironment in multiple cancer models in female mice. Targeting iRhom1 together with chemotherapy could represent a strategy to overcome chemo-immune resistance in cancer treatment.

Use of recombinant microRNAs as antimetabolites to inhibit human non-small cell lung cancer

During the development of therapeutic microRNAs (miRNAs or miRs), it is essential to define their pharmacological actions. Rather, miRNA research and therapy mainly use miRNA mimics synthesized in vitro. After experimental screening of unique recombinant miRNAs produced in vivo, three lead antiproliferative miRNAs against human NSCLC cells, miR-22-3p, miR-9-5p, and miR-218-5p, were revealed to target folate metabolism by bioinformatic analyses. Recombinant miR-22-3p, miR-9-5p, and miR-218-5p were shown to regulate key folate metabolic enzymes to inhibit folate metabolism and subsequently alter amino acid metabolome in NSCLC A549 and H1975 cells. Isotope tracing studies further confirmed the disruption of one-carbon transfer from serine to folate metabolites by all three miRNAs, inhibition of glucose uptake by miR-22-3p, and reduction of serine biosynthesis from glucose by miR-9-5p and -218-5p in NSCLC cells. With greater activities to interrupt NSCLC cell respiration, glycolysis, and colony formation than miR-9-5p and -218-5p, recombinant miR-22-3p was effective to reduce tumor growth in two NSCLC patient-derived xenograft mouse models without causing any toxicity. These results establish a common antifolate mechanism and differential actions on glucose uptake and metabolism for three lead anticancer miRNAs as well as antitumor efficacy for miR-22-3p nanomedicine, which shall provide insight into developing antimetabolite RNA therapies.

Androgen receptor transcriptional activity is required for heregulin-1β-mediated nuclear localization of the HER3/ErbB3 receptor tyrosine kinase

Prostate cancer is initially regulated by the androgen receptor (AR), a ligand-activated, transcription factor, and is in a hormone-dependent state (hormone-sensitive prostate cancer (HSPC)), but eventually becomes androgen-refractory (castration-resistant prostate cancer (CRPC)) because of mechanisms that bypass the AR, including by activation of ErbB3, a member of the epidermal growth factor receptor family. ErbB3 is synthesized in the cytoplasm and transported to the plasma membrane for ligand binding and dimerization, where it regulates downstream signaling, but nuclear forms are reported. Here, we demonstrate in prostatectomy samples that ErbB3 nuclear localization is observed in malignant, but not benign prostate, and that cytoplasmic (but not nuclear) ErbB3 correlated positively with AR expression but negatively with AR transcriptional activity. In support of the latter, androgen depletion upregulated cytoplasmic, but not nuclear ErbB3, while in vivo studies showed that castration suppressed ErbB3 nuclear localization in HSPC, but not CRPC tumors. In vitro treatment with the ErbB3 ligand heregulin-1β (HRG) induced ErbB3 nuclear localization, which was androgen-regulated in HSPC but not in CRPC. In turn, HRG upregulated AR transcriptional activity in CRPC but not in HSPC cells. Positive correlation between ErbB3 and AR expression was demonstrated in AR-null PC-3 cells where stable transfection of AR restored HRG-induced ErbB3 nuclear transport, while AR knockdown in LNCaP reduced cytoplasmic ErbB3. Mutations of ErbB3's kinase domain did not affect its localization but was responsible for cell viability in CRPC cells. Taken together, we conclude that AR expression regulated ErbB3 expression, its transcriptional activity suppressed ErbB3 nuclear translocation, and HRG binding to ErbB3 promoted it.

Erratum: Author correction to 'Bioengineered miR-124-3p prodrug selectively alters the proteome of human carcinoma cells to control multiple cellular components and lung metastasis in vivo' [Acta Pharmaceutica Sinica B 11 (2021) 3950-3965]

[This corrects the article DOI: 10.1016/j.apsb.2021.07.027.].

Bioengineered BERA-Wnt5a siRNA Targeting Wnt5a/FZD2 Signaling Suppresses Advanced Prostate Cancer Tumor Growth and Enhances Enzalutamide Treatment

The next-generation antiandrogen drugs such as enzalutamide and abiraterone extend survival times and improve quality of life in patients with advanced prostate cancer. However, resistance to both drugs occurs frequently through mechanisms that are incompletely understood. Wnt signaling, particularly through Wnt5a, plays vital roles in promoting prostate cancer progression and induction of resistance to enzalutamide and abiraterone. Development of novel strategies targeting Wnt5a to overcome resistance is an urgent need. In this study, we demonstrated that Wnt5a/FZD2-mediated noncanonical Wnt pathway is overexpressed in enzalutamide-resistant prostate cancer. In patient databases, both the levels of Wnt5a and FZD2 expression are upregulated upon the development of enzalutamide resistance and correlate with higher Gleason score, biochemical recurrence, and metastatic status, and with shortened disease-free survival duration. Blocking Wnt5a/FZD2 signal transduction not only diminished the activation of noncanonical Wnt signaling pathway, but also suppressed the constitutively activated androgen receptor (AR) and AR variants. Furthermore, we developed a novel bioengineered BERA-Wnt5a siRNA construct and demonstrated that inhibition of Wnt5a expression by the BERA-Wnt5a siRNA significantly suppressed tumor growth and enhanced enzalutamide treatment in vivo. These results indicate that Wnt5a/FZD2 signal pathway plays a critical role in promoting enzalutamide resistance, and targeting this pathway by BERA-Wnt5a siRNA can be developed as a potential therapy to treat advanced prostate cancer.

Machine learning analysis including social determinants of health for predication of mortality following transcatheter aortic valve implantation: a single center experience

Funding Acknowledgements

Type of funding sources: None.

Introduction

Social determinants of health (SDOH) are increasingly being recognized as critical, independent prognosticators in cardiovascular disease. Despite this, little is known about the role of SDOH in predicting outcomes following transcatheter aortic valve implantation (TAVI).

Purpose

To assess the value of adding census-derived SDOH in developing machine learning (ML) models for prediction of all-cause mortality in patients following TAVI.

Methods

A total of 398 patients, who underwent TAVI in 2019, were studied. Clinical, demographic, echocardiographic (echo) and census-derived SDOH data were collected. All-cause mortality at 1 year was the endpoint. A general linear ML model was fit with 100 iterations and a 70:30 training-test split. We compared the predictive performance of the model with and without adding SDOH. The SDOH included in the ML model were race (white vs. non-white), % zip code population as female, and zip code average yearly income less than $45,000.

Results

Baseline SDOH, demographic, clinical, and echo data are shown in Table 1. Following univariate and multivariate predictor analysis, the following input data were used for the ML model without the SDOH: post TAVI all-cause hospitalizations, history of outpatient hemodialysis, atrial fibrillation, heart failure with reduced ejection fraction, myocardial infarction, coronary artery disease and beta-blockers. The ML model with SDOH used the same input as well as the SDOH variables. The model with vs. without SDOH had a median AUC of 0.75 vs. 0.73 (p = 0.9957).

Conclusions

Despite not reaching statistical significance, our ML model provides a holistic picture of mortality predictors. Larger studies are needed to more assess the predictive value of SDOH post TAVI. Abstract Figure. Baseline patient characteristics  Abstract Figure. ML Model: Area Under Curve

Exploring the therapeutic potential of Neem (Azadirachta Indica) for the treatment of prostate cancer: a literature review

Background and Objective

Multiple studies have demonstrated the medical potency of plant extracts and specific phytochemicals as therapeutics for prostate cancer (PCa) patients. Of note, the Neem plant known for its role as an antibiotic and anti-inflammatory is underexplored with an untapped potential for further development. This review focuses on extracts and phytochemicals derived from the Neem tree (Latin name; Azadirachta indica), commonly used throughout Southeast Asia for the prevention and treatment of a wide array of diseases including cancer. To date, there are more than 130 biologically active compounds that have been isolated from the Neem tree including azadirachtin, nimbolinin, nimbin, nimbidin, nimbidol, which have demonstrated a wide range of biological activities including anti-microbial, anti-fertility, anti-inflammatory, anti-arthritic, hepatoprotective, anti-diabetic, anti-ulcer, and anti-cancer effects. Very few scientific reports focus on the benefits of Neem in PCa, even though this herb has been used to prevent the disease and its progression for years in complementary and alternative medicine.

Methods

We used the search engines like PubMed, InCommon and Google using the key words: “Neem”, “Cancer”, “Prostate Cancer” and related words to find the information and data within the time frame from 1980–2022 for our article study.

Key Content and Findings

Here, we provide an overview of Neem extracts and phytochemical derivatives with a focus on their known potential and ability to inhibit specific cellular signaling pathways and processes which drive PCa incidence and progression.

Conclusions

The information presented here indicate that Neem and its derivatives have a therapeutic potential for the treatment of PCa when used as a single agent or in combination with conventional chemotherapeutics.

Bioengineered miR-124-3p prodrug selectively alters the proteome of human carcinoma cells to control multiple cellular components and lung metastasis in vivo

With the understanding of microRNA (miRNA or miR) functions in tumor initiation, progression, and metastasis, efforts are underway to develop new miRNA-based therapies. Very recently, we demonstrated effectiveness of a novel humanized bioengineered miR-124-3p prodrug in controlling spontaneous lung metastasis in mouse models. This study was to investigate the molecular and cellular mechanisms by which miR-124-3p controls tumor metastasis. Proteomics study identified a set of proteins selectively and significantly downregulated by bioengineered miR-124-3p in A549 cells, which were assembled into multiple cellular components critical for metastatic potential. Among them, plectin (PLEC) was verified as a new direct target for miR-124-3p that links cytoskeleton components and junctions. In miR-124-3p-treated lung cancer and osteosarcoma cells, protein levels of vimentin, talin 1 (TLN1), integrin beta-1 (ITGB1), IQ motif containing GTPase activating protein 1 (IQGAP1), cadherin 2 or N-cadherin (CDH2), and junctional adhesion molecule A (F11R or JAMA or JAM1) decreased, causing remodeling of cytoskeletons and disruption of cell-cell junctions. Furthermore, miR-124-3p sharply suppressed the formation of focal adhesion plaques, leading to reduced cell adhesion capacity. Additionally, efficacy and safety of biologic miR-124-3p therapy was established in an aggressive experimental metastasis mouse model in vivo. These results connect miR-124-3p-PLEC signaling to other elements in the control of cytoskeleton, cell junctions, and adhesion essential for cancer cell invasion and extravasation towards metastasis, and support the promise of miR-124 therapy.

In vivo fermentation production of humanized noncoding RNAs carrying payload miRNAs for targeted anticancer therapy

Rationale: Noncoding RNAs (ncRNAs) such as microRNAs (miRs or miRNAs) play important roles in the control of cellular processes through posttranscriptional gene regulation. However, ncRNA research is limited to utilizing RNA agents synthesized in vitro. Recombinant RNAs produced and folded in living cells shall better recapitulate biologic RNAs.

Methods: Herein, we developed a novel platform for in vivo fermentation production of humanized recombinant ncRNA molecules, namely hBERAs, carrying payload miRNAs or siRNAs. Target hBERAs were purified by anion exchange FPLC method. Functions of hBERA/miRNAs were investigated in human carcinoma cells and antitumor activities were determined in orthotopic osteosarcoma xenograft spontaneous lung metastasis mouse models.

Results: Proper human tRNAs were identified to couple with optimal hsa-pre-miR-34a as new fully-humanized ncRNA carriers to accommodate warhead miRNAs or siRNAs. A group of 30 target hBERAs were all heterogeneously overexpressed (each accounting for >40% of total bacterial RNA), which facilitated large-scale production (8-31 mg of individual hBERAs from 1L bacterial culture). Model hBERA/miR-34a-5p and miR-124-3p were selectively processed to warhead miRNAs in human carcinoma cells to modulate target gene expression, enhance apoptosis and inhibit invasiveness. In addition, bioengineered miR-34a-5p and miR-124-3p agents both reduced orthotopic osteosarcoma xenograft tumor growth and spontaneous pulmonary metastases significantly.

Conclusion: This novel ncRNA bioengineering technology and resulting recombinant ncRNAs are unique additions to conventional technologies and tools for basic research and drug development.

Single bioengineered ncRNA molecule for dual-targeting toward the control of non-small cell lung cancer patient-derived xenograft tumor growth

Lung cancer remains the leading cause of cancer deaths worldwide and accounts for more than 22% of all cancer-related deaths in the US. Developing new therapies is essential to combat against deadly lung cancer, especially the most common type, non-small cell lung cancer (NSCLC). With the discovery of genome-derived functional small noncoding RNA (ncRNA), namely microRNAs (miRNA or miR), restoration of oncolytic miRNAs lost or downregulated in NSCLC cells represents a new therapeutic strategy. Very recently, we have developed a novel technology that achieves in vivo fermentation production of bioengineered miRNA agents (BERA) for research and development. In this study, we aimed at simultaneously introducing two miRNAs into NSCLC cells by using single recombinant "combinatorial BERA" (CO-BERA) molecule. Our studies show that single CO-BERA molecule (e.g., let-7c/miR-124) was successfully processed to two miRNAs (e.g., let-7c-5p and miR-124-3p) to combinatorially regulate the expression of multiple targets (e.g., RAS, VAMP3 and CDK6) in human NSCLC cells, exhibiting greater efficacy than respective BERA miRNAs in the inhibition of cell viability and colony formation. Furthermore, we demonstrate that CO-BERA let-7c/miR-124-loaded lipopolyplex nanomedicine was the most effective among tested RNAs in the control of tumor growth in NSCLC patient-derived xenograft mouse models. The anti-tumor activity of CO-BERA let-7c/miR-124 was associated with the suppression of RAS and CDK6 expression, and enhancement of apoptosis. These results support the concept to use single ncRNA agent for dual-targeting and offer insight into developing new RNA therapeutics for the treatment of lethal NSCLC.

Expression and Purification of tRNA/ pre-miRNA-Based Recombinant Noncoding RNAs

Research on RNA function and therapeutic potential is dominated by the use of chemoengineered RNA mimics. Recent efforts have led to the establishment of novel technologies for the production of recombinant or bioengineered RNA molecules, which should better recapitulate the structures, functions and safety profiles of natural RNAs because both are produced and folded in living cells. Herein, we describe a robust approach for reproducible fermentation production of bioengineered RNA agents (BERAs) carrying warhead miRNAs, siRNAs, aptamers, or other forms of small RNAs, based upon an optimal hybrid tRNA/pre-miRNA carrier. Target BERA/sRNAs are readily purified by fast protein liquid chromatography (FPLC) to a high degree of homogeneity (>97%). This approach offers a consistent high-level expression (>30% of total bacterial RNAs) and large-scale production of ready-to-use BERAs (multiple to tens milligrams from 1 L bacterial culture).

The HMOX1 Pathway as a Promising Target for the Treatment and Prevention of SARS-CoV-2 of 2019 (COVID-19)

The coronavirus disease of 2019 (COVID-19) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global pandemic with increasing incidence and mortality rates. Recent evidence based on the cytokine profiles of severe COVID-19 cases suggests an overstimulation of macrophages and monocytes associated with reduced T-cell abundance (lymphopenia) in patients infected with SARS-CoV-2. The SARS-CoV-2 open reading frame 3 a (ORF3a) protein was found to bind to the human HMOX1 protein at a high confidence through high-throughput screening experiments. The HMOX1 pathway can inhibit platelet aggregation, and can have anti-thrombotic and anti-inflammatory properties, amongst others, all of which are critical medical conditions observed in COVID-19 patients. Here, we review the potential of modulating the HMOX1-ORF3a nexus to regulate the innate immune response for therapeutic benefits in COVID-19 patients. We also review other potential treatment strategies and suggest novel synthetic and natural compounds that may have the potential for future development in clinic.

Genistein Combined Polysaccharide (GCP) Can Inhibit Intracrine Androgen Synthesis in Prostate Cancer Cells

Our group and others have previously shown that genistein combined polysaccharide (GCP), an aglycone isoflavone-rich extract with high bioavailability and low toxicity, can inhibit prostate cancer (CaP) cell growth and survival as well as androgen receptor (AR) activity. We now elucidate the mechanism by which this may occur using LNCaP and PC-346C CaP cell lines; GCP can inhibit intracrine androgen synthesis in CaP cells. UPLC-MS/MS and qPCR analyses demonstrated that GCP can mediate a ~3-fold decrease in testosterone levels (p < 0.001) and cause decreased expression of intracrine androgen synthesis pathway enzymes (~2.5-fold decrease of 3βHSD (p < 0.001), 17βHSD (p < 0.001), CYP17A (p < 0.01), SRB1 (p < 0.0001), and StAR (p < 0.01)), respectively. Reverse-phase HPLC fractionation and bioassay identified three active GCP fractions. Subsequent NMR and LC-MS analysis of the fraction with the highest level of activity, fraction 40, identified genistein as the primary active component of GCP responsible for its anti-proliferative, pro-apoptotic, and anti-AR activity. GCP, fraction 40, and genistein all mediated at least a ~2-fold change in these biological activities relative to vehicle control (p < 0.001). Genistein caused similar decreases in the expression of 17βHSD and CYP17A (2.5-fold (p < 0.001) and 1.5-fold decrease (p < 0.01), respectively) compared to GCP, however it did not cause altered expression of the other intracrine androgen synthesis pathway enzymes; 3βHSD, SRB1, and StAR. Our combined data indicate that GCP and/or genistein may have clinical utility and that further pre-clinical studies are warranted.

Abstract B083: Dysregulation of the AR-Nrdp1-ErbB3 axis occurs in African American prostate cancer patients and is associated with worse outcomes

Background: We previously showed that Nrdp1, an E3 ubiquitin ligase, is transcriptionally regulated by the androgen receptor (AR) in prostate cancer (CaP) cells and that Nrdp1 can post-translationally regulate ErbB3 (an EGFR family member) levels via ubiquitination and subsequent proteasomal degradation. Increased levels of ErbB3 are associated with worse CaP patient outcome. The goal of the current study was to determine whether dysregulation of the AR-Nrdp1-ErbB3 axis contributes to prostate cancer health disparities for African American (AA) men, and to identify the underlying mechanisms involved. Methods: Expression levels and localization of AR, Nrdp1, and ErbB3 were assessed in a total of 208 CaP patient samples (50 African American (AA) and 158 Caucasian (CA) CaP patients) and two cell lines (LNCaP (CA) and MDAPCa2b (AA)). Expression levels and localization of these molecules were determined by immunohistochemistry (IHC) and subcellular fractionation and western blot. A combination of knockdown (siRNA), forced overexpression (Nrdp1-FLAG construct), and treatment with enzalutamide or synthetic androgen (R1881) experiments were employed to investigate the relationship between AR, Nrdp1, and ErbB3 expression levels and localization and to identify differences in AA and CA cell lines. Immunoprecipitation allowed for investigation of the mechanisms which facilitate nuclear transport of Nrdp1. Results: A statistically significant negative association between cytoplasmic levels of AR (AR C) and nuclear Nrdp1 (Nrdp1 N) exists in both Caucasian (CA) and African American (AA) prostate cancer (CaP) patients, but this association was stronger in AA patients compared to CA patients (Spearman correlation coefficient of -0.62 for AA patients, and -0.36 for CA patients). Increased nuclear Nrdp1 expression levels were associated with increased 5-year survival rates, and reduced nuclear Nrdp1 expression levels predicted biochemical recurrence (AUC 0.63). Dysregulation of the AR-Nrdp1-ErbB3 axis in AA CaP cells was also observed in cell line studies; AA CaP cells expressed significantly lower levels of both total and nuclear Nrdp1 compared to their CA CaP counterparts. Manipulation of AR expression levels and localization via knockdown and inhibition with enzalutamide had a lesser impact on Nrdp1 expression levels and localization in AA versus CA CaP cells. Immunoprecipitation studies demonstrated that Nrdp1 can bind to AR in CA CaP cells but not AA CaP cells. Conclusions: Our combined data indicate that dysregulation of the AR-Nrdp1-ErbB3 axis occurs to a larger extent in AA than CA CaP cells and that this can contribute to worse patient outcomes. Our data also indicate that lack of binding between AR and Nrdp1 in AA CaP cells may account for the lower levels of nuclear Nrdp1 observed in AA CaP cells. Further understanding of the mechanisms which regulate Nrdp1 levels and localization may allow for the development of treatments which help abrogate cancer health disparities.

Citation Format: Anhao Sam, Shawna Evans, Elizabeth Browning, Sheryl Krig, Neelu Batra, Thomas Steele, Salma Siddqui, Paramita Ghosh, Ruth Vinall. Dysregulation of the AR-Nrdp1-ErbB3 axis occurs in African American prostate cancer patients and is associated with worse outcomes [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B083.

Novel approaches for efficient in vivo fermentation production of noncoding RNAs

Genome-derived noncoding RNAs (ncRNAs), including microRNAs (miRNAs), small interfering RNAs (siRNAs), and long noncoding RNAs (lncRNAs), play an essential role in the control of target gene expression underlying various cellular processes, and dysregulation of ncRNAs is involved in the pathogenesis and progression of various diseases in virtually all species including humans. Understanding ncRNA biology has opened new avenues to develop novel RNA-based therapeutics. Presently, ncRNA research and drug development is dominated by the use of ncRNA mimics that are synthesized chemically in vitro and supplemented with extensive and various types of artificial modifications and thus may not necessarily recapitulate the properties of natural RNAs generated and folded in living cells in vivo. Therefore, there are growing interests in developing novel technologies for in vivo production of RNA molecules. The two most recent major breakthroughs in achieving an efficient, large-scale, and cost-effective fermentation production of recombinant or bioengineered RNAs (e.g., tens of milligrams from 1 L of bacterial culture) are (1) using stable RNA carriers and (2) direct overexpression in RNase III-deficient bacteria, while other approaches offer a low yield (e.g., nano- to microgram scales per liter). In this article, we highlight these novel microbial fermentation-based technologies that have shifted the paradigm to the production of true biological ncRNA molecules for research and development.

Bioengineered miR-328-3p modulates GLUT1-mediated glucose uptake and metabolism to exert synergistic antiproliferative effects with chemotherapeutics

MicroRNAs (miRNAs or miRs) are small noncoding RNAs derived from genome to control target gene expression. Recently we have developed a novel platform permitting high-yield production of bioengineered miRNA agents (BERA). This study is to produce and utilize novel fully-humanized BERA/miR-328-3p molecule (hBERA/miR-328) to delineate the role of miR-328-3p in controlling nutrient uptake essential for cell metabolism. We first demonstrated successful high-level expression of hBERA/miR-328 in bacteria and purification to high degree of homogeneity (>98%). Biologic miR-328-3p prodrug was selectively processed to miR-328-3p to suppress the growth of highly-proliferative human osteosarcoma (OS) cells. Besides glucose transporter protein type 1, gene symbol solute carrier family 2 member 1 (GLUT1/SLC2A1), we identified and verified large neutral amino acid transporter 1, gene symbol solute carrier family 7 member 5 (LAT1/SLC7A5) as a direct target for miR-328-3p. While reduction of LAT1 protein levels by miR-328-3p did not alter homeostasis of amino acids within OS cells, suppression of GLUT1 led to a significantly lower glucose uptake and decline in intracellular levels of glucose and glycolytic metabolite lactate. Moreover, combination treatment with hBERA/miR-328 and cisplatin or doxorubicin exerted a strong synergism in the inhibition of OS cell proliferation. These findings support the utility of novel bioengineered RNA molecules and establish an important role of miR-328-3p in the control of nutrient transport and homeostasis behind cancer metabolism.

A Novel Bioengineered miR-127 Prodrug Suppresses the Growth and Metastatic Potential of Triple-Negative Breast Cancer Cells

miR-127 is downregulated in breast cancer, where it has been shown to suppress the proliferation, migration, and invasion of breast cancer cells. In triple-negative breast cancer (TNBC), miR-127 downregulation correlates with decreased disease-free and overall patient survival. Tumor suppressor miRNAs may hold therapeutic promise but progress has been limited by several factors, including the lability and high cost of miRNA mimics. Here, we take a novel approach to produce a miR-127 prodrug (miR-127^PD), which we demonstrate is processed to mature, functional miR-127-3p in TNBC tumor cells. miR-127^PD decreased the viability and motility of TNBC cells, sensitized TNBC cells to chemotherapy, and restricted the TNBC stem cell population. Furthermore, systemic delivery of miR-127^PD suppressed tumor growth of MDA-MB-231 and MDA-MB-468 TNBC cells and spontaneous metastasis of MDA-MB-231 cells. In addition, CERK, NANOS1, FOXO6, SOX11, SOX12, FASN, and SUSD2 were identified as novel, functionally important targets of miR-127. In conclusion, our study demonstrates that miR-127 functions as a tumor and metastasis suppressor in TNBC and that delivery of miR-127 may hold promise as a novel therapy. SIGNIFICANCE: Exogenous administration of miR-127, which is functionally activated in target cells, inhibits growth and spontaneous metastasis of triple-negative breast cancer.

Cladosporium sphaerospermum causing brain abscess, a saprophyte turning pathogen: Case and review of published reports

Emergence of saprophytic fungi thriving in dead plant material and soil as opportunistic human pathogens is of great concern. Cladosporium species are environmental saprophytes reported to cause various superficial and invasive fungal infections worldwide. C. sphaerospermum, a predominantly indoor fungus has been reported from cases of meningitis, subcutaneous and pulmonary fungal infections in the past. Herein we report the first case of cerebral abscess due to C. sphaerospermum in an immunocompetent host who was successfully managed by combined medical and surgical therapy.

Bioengineered miR-27b-3p and miR-328-3p modulate drug metabolism and disposition via the regulation of target ADME gene expression

Drug-metabolizing enzymes, transporters, and nuclear receptors are essential for the absorption, distribution, metabolism, and excretion (ADME) of drugs and xenobiotics. MicroRNAs participate in the regulation of ADME gene expression via imperfect complementary Watson-Crick base pairings with target transcripts. We have previously reported that Cytochrome P450 3A4 (CYP3A4) and ATP-binding cassette sub-family G member 2 (ABCG2) are regulated by miR-27b-3p and miR-328-3p, respectively. Here we employed our newly established RNA bioengineering technology to produce bioengineered RNA agents (BERA), namely BERA/miR-27b-3p and BERA/miR-328-3p, via fermentation. When introduced into human cells, BERA/miR-27b-3p and BERA/miR-328-3p were selectively processed to target miRNAs and thus knock down CYP3A4 and ABCG2 mRNA and their protein levels, respectively, as compared to cells treated with vehicle or control RNA. Consequently, BERA/miR-27b-3p led to a lower midazolam 1'-hydroxylase activity, indicating the reduction of CYP3A4 activity. Likewise, BERA/miR-328-3p treatment elevated the intracellular accumulation of anticancer drug mitoxantrone, a classic substrate of ABCG2, hence sensitized the cells to chemotherapy. The results indicate that biologic miRNA agents made by RNA biotechnology may be applied to research on miRNA functions in the regulation of drug metabolism and disposition that could provide insights into the development of more effective therapies.

Abstract 3535: Differential expression and localization of the E3 ubiquitin ligase Nrdp1 in African American versus Caucasian American prostate cancer cells

Despite a recent decrease in overall incidence of prostate cancer (CaP), CaP incidence continues to be much higher among men of African origin living in the United States (223.9 men per 100,000) compared to those of European origin (139.9 men per 100,000). Also, the CaP age-specific mortality rates are 2.4 times greater among African-American (AA) compared with European American (EA) men. The causes for these differences are multifactorial, but include genetic effects that contribute to CaP-associated health disparity. We previously showed that the androgen receptor (AR) can suppress levels of the receptor tyrosine kinase ErbB3, a molecule that is known to drive CaP progression, by stimulating the E3 ubiquitin ligase Nrdp1 (also called RNF41 or FLRF). The goals of the current study were to determine whether differential expression and/or localization of Nrdp1 contribute to CaP-associated health disparities, and to further elucidate the mechanisms by which regulation of Nrdp1 levels and localization occurs. Immunohistochemistry (IHC) in prostate tissue determined that nuclear Nrdp1 levels are significantly lower in AA CaP patients (n=19) versus CA CaP patients (n=121) with localized disease (p=0.008). A similar association was observed in CaP cell lines; immunofluorescence (IF) analyses demonstrated MDAPCa2b and E006 (cell lines derived from AA CaP patients) express significantly lower levels of nuclear Nrdp1 compared to LNCaP, CWR22Rv1, C4-2, and C4-2B (cell lines derived from CA CaP patients). Western blot and qPCR determined that Nrdp1 levels are lower in AA versus CA CaP cells (MDAPCa2b express ~2-fold less Nrdp1 protein and mRNA levels compared to LNCaP), and that androgen withdrawal has a bigger impact on Nrdp1 expression levels in AA CaP cells (2-fold decrease in MDAPCa2b compared to ~1.2-fold decrease in LNCaP). Proteasomal regulation of Nrdp1 also occurs; treatment with MG132 resulted in accumulation of Nrdp1 in both AA and CA CaP cell lines. Interestingly, altering androgen and/or AR levels also affected Nrdp1 localization (IF analyses) as well as the ability of Nrdp1 to mediate CaP cell apoptosis (flow cytometry). In summary, we demonstrate that Nrdp1 is differentially expressed in AA versus CA CaP patients as well as in AA versus CA CaP-patient derived cell lines, and that androgen withdrawal has a bigger impact on Nrdp1 expression in AA CaP cell lines. We also demonstrate that androgen/AR is involved in determining Nrdp1 localization, and that Nrdp1 can mediate CaP cell apoptosis in the presence of AR. The combined data, and the knowledge that Nrdp1 regulates ErbB3 levels, suggest that differential expression of Nrdp1 in AA versus CA CaP may contribute to CaP-associated health disparities and may occur as a result of dysregulation of the regulation of Nrdp1 by androgen/AR.

Citation Format: Neelu Batra, Sheryl Krig, Anhao Sam, Katelyn Macias, Rosalinda Savoy, Salma Siddiqui, Frank Melgoza, Leandro D'Abronzo, Sidhartha Hazari, Blythe Durbin-Johnson, Paramita Ghosh, Ruth L. Vinall. Differential expression and localization of the E3 ubiquitin ligase Nrdp1 in African American versus Caucasian American prostate cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3535.

Bioengineered Noncoding RNAs Selectively Change Cellular miRNome Profiles for Cancer Therapy

Noncoding RNAs (ncRNAs) produced in live cells may better reflect intracellular ncRNAs for research and therapy. Attempts were made to produce biologic ncRNAs, but at low yield or success rate. Here we first report a new ncRNA bioengineering technology using more stable ncRNA carrier (nCAR) containing a pre-miR-34a derivative identified by rational design and experimental validation. This approach offered a remarkable higher level expression (40%-80% of total RNAs) of recombinant ncRNAs in bacteria and gave an 80% success rate (33 of 42 ncRNAs). New FPLC and spin-column based methods were also developed for large- and small-scale purification of milligrams and micrograms of recombinant ncRNAs from half liter and milliliters of bacterial culture, respectively. We then used two bioengineered nCAR/miRNAs to demonstrate the selective release of target miRNAs into human cells, which were revealed to be Dicer dependent (miR-34a-5p) or independent (miR-124a-3p), and subsequent changes of miRNome and transcriptome profiles. miRNA enrichment analyses of altered transcriptome confirmed the specificity of nCAR/miRNAs in target gene regulation. Furthermore, nCAR assembled miR-34a-5p and miR-124-3p were active in suppressing human lung carcinoma cell proliferation through modulation of target gene expression (e.g., cMET and CDK6 for miR-34a-5p; STAT3 and ABCC4 for miR-124-3p). In addition, bioengineered miRNA molecules were effective in controlling metastatic lung xenograft progression, as demonstrated by live animal and ex vivo lung tissue bioluminescent imaging as well as histopathological examination. This novel ncRNA bioengineering platform can be easily adapted to produce various ncRNA molecules, and biologic ncRNAs hold the promise as new cancer therapeutics.

Abstract P6-04-04: Maternal embryonic leucine zipper kinase (MELK) is a novel radiosensitizing and therapeutic target and is independently prognostic in triple-negative breast cancer

Background: While effective targeted therapies exist for estrogen receptor (ER)-positive and HER2/neu-positive breast cancer, no such effective therapies exist for ER-negative, PR-negative, and HER2-negative (“triple negative”) cancers. Given the lack of targeted agents for triple negative (TN) disease and their relative radiation insensitivity, it is clear that additional targets for treatment are critically needed.

Our previous work identified one such novel molecular target as maternal embryonic leucine zipper kinase (MELK), and we sought to investigate the impact of MELK expression on radiation response and patient outcomes.

Methods: Using gene expression arrays, we interrogated the expression of MELK in 2,061 breast tumor samples as well as a panel of 51 breast cancer cell lines. We measured protein expression in TN cancers with western blotting and used clonogenic survival assays to quantitate radiosensitivity of BCC lines at baseline and after MELK inhibition. Multiple datasets were used to evaluate the prognostic import of MELK. Kaplan-Meier analysis using local control and survival data was performed. Chi squared scores were calculated to determine significance and hazard ratios (HR) and 95% confidence intervals (CI) were calculated. A Cox proportional hazards model was constructed to identify potential factors of survival.

Results: We demonstrate that MELK expression is significantly elevated in human TN breast cancers, including chemoradiation resistant tumors (305 tumors compared to 1756 non-TN breast tumors; p-value 7.5 e-21). MELK protein and RNA expression is induced by ionizing radiation (5.6-7.5 fold at 72 hours, p-value &lt;0.01). We characterized the radiation sensitivity of BCC lines and demonstrated that MELK expression is significantly correlated with radioresistance (as measured by clonogenic survival) in 21 breast cancer cell lines (R: 0.62, p-value 0.003). Inhibition of MELK using both siRNA and small molecule inhibitors induces radiation sensitivity in vitro with and enhancement ratio (ER) of 1.5-1.6. We demonstrate that high MELK expression is strongly correlated with p53 mutation positive status (p-value &lt;0.001). Finally, local control and survival analyses of patients with BC showed that those patients whose tumors have high expression of MELK have significantly higher rates of LR after radiation and an overall poorer prognosis than patients with low expression of MELK (HR for LR 1.89-2.23, p-value 0.001; HR for overall survival 1.46-3.3; p-value &lt;0.001 in 3 independent datasets). In multivariate analysis of all patients, only MELK expression and grade were significantly associated with worse local recurrence free (LRF) survival with a HR of 1.35 (95% CI 1.05-1.72, p-value &lt; 0.01).

Conclusion: Here, we identify MELK as a potential biomarker of radioresistance and target for radiosensitization in triple negative breast cancers. MELK overexpression was associated with local failure across multiple data sets. MVA identified MELK as the strongest factor associated with poor local control. Our results support the rationale for developing clinical strategies to inhibit MELK as a novel target in triple-negative breast cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-04-04.

Genetic polymorphisms in the P2X7 gene and its association with susceptibility to tuberculosis

BACKGROUND

Several studies have reported the influence of genetic variations on susceptibility to tuberculosis (TB). Polymorphism in P2X7 gene coding for P2X7 receptor present on macrophages has been linked to TB in different populations.

OBJECTIVE

To assess the role of P2X7 gene -762T/C and -1513A/C polymorphisms in TB susceptibility.

DESIGN

In a case-control study, polymerase chain reaction (PCR) amplification of genomic DNA extracted from peripheral blood samples of cases and controls was followed by restriction fragment length polymorphism or allele-specific PCR.

RESULTS

The 1513C allele was found to be associated with TB susceptibility (P = 0.02, OR for variant C allele 1.33, 95%CI 1.03-1.73). A significant protective association against TB was found for -762T/C polymorphism (P < 0.01, OR for variant C allele 0.72, 95%CI 0.57-0.91). On classifying samples on the basis of sex, only males showed a significant association between P2X7 -1513A/C and P2X7 -762T/C and TB in the present study.

CONCLUSION

A significant association of 762T/C and 1513A/C polymorphisms with TB in the P2X7 gene was found in our study population. A sex bias, with only males showing a significant association with the disease, is the first report of this kind. Genetic studies for the characterisation of the susceptibility genes can help to gain a better understanding of TB pathogenesis.

Applications of soluble, encapsulated and cross-linked peroxidases from Sapindus mukorossi for the removal of phenolic compounds

Peroxidases have been known to polymerize phenolic compounds and precipitate them from solution. Sapindus peroxidases (SPases) were extracted from the leaves of Sapindus mukorossi and precipitated with four volumes of chilled methanol. Soluble, encapsulated and cross-linked forms of enzymes were used for the removal of phenolic compounds (initial concentration 1.0 mM) in a stirred batch reactor. Calcium alginate beads were prepared using sodium alginate and calcium chloride at 1.5% and 5.0% (w/v), respectively. Sodium alginate and glutaraldehyde at 1.0% (w/v) and 0.8% (v/v), respectively, were optimized for cross-linking of SPases. The maximal removal of 2-chlorophenol was found in the buffers ofpH range 4-7 and at 30-60 degrees C in the presence of 1.2 mM H2O2 by soluble enzymes, but encapsulated and cross-linked enzymes worked well at pH 5 and at 50 degrees C in the presence of 0.8 mM H2O2. The optimized doses of soluble, encapsulated and cross-linked SPases were 1.2, 4.2 and 1.2 mg/mL, respectively, for the removal of phenolic compounds. Encapsulated and cross-linked enzymes showed a lower efficiency than soluble enzyme but can be reused in multiple cycles for the removal of phenolic compounds.

Association of mannose-binding lectin gene polymorphism with tuberculosis susceptibility and sputum conversion time

Mannose-binding lectin (MBL) plays an important role in innate immunity. The effect of low MBL levels producing variants of MBL2 gene on tuberculosis (TB) has been controversial with some studies reporting it to confer protection against the disease, whereas others estimating a susceptibility relation. Other than conducting a case-control study to evaluate the role of MBL A/B polymorphism on TB, we conducted a longitudinal study to check whether this MBL variant can influence the host response to Mycobacterium tuberculosis infection. A total of 357 TB patients (286 pulmonary TB, 71 extrapulmonary (EP) TB) and 392 healthy controls belonging to same ethnicity were included in the study. We found the mutant allele 'B' allele confers a protective role against TB in our study population. This effect was absent in EP patients. On stratification on the basis of sex, the protective role of the 'B' allele was found to be limited to females only and males reported no significant difference. No effect of MBL A/B polymorphism on sputum conversion time was reported. We conclude that MBL 'B' allele is associated with protection against TB, but no influence was found on sputum conversion rate.

Mechanism of gallic acid biosynthesis in bacteria (Escherichia coli) and walnut (Juglans regia)

Gallic acid (GA), a key intermediate in the synthesis of plant hydrolysable tannins, is also a primary anti-inflammatory, cardio-protective agent found in wine, tea, and cocoa. In this publication, we reveal the identity of a gene and encoded protein essential for GA synthesis. Although it has long been recognized that plants, bacteria, and fungi synthesize and accumulate GA, the pathway leading to its synthesis was largely unknown. Here we provide evidence that shikimate dehydrogenase (SDH), a shikimate pathway enzyme essential for aromatic amino acid synthesis, is also required for GA production. Escherichia coli (E. coli) aroE mutants lacking a functional SDH can be complemented with the plant enzyme such that they grew on media lacking aromatic amino acids and produced GA in vitro. Transgenic Nicotiana tabacum lines expressing a Juglans regia SDH exhibited a 500% increase in GA accumulation. The J. regia and E. coli SDH was purified via overexpression in E. coli and used to measure substrate and cofactor kinetics, following reduction of NADP(+) to NADPH. Reversed-phase liquid chromatography coupled to electrospray mass spectrometry (RP-LC/ESI-MS) was used to quantify and validate GA production through dehydrogenation of 3-dehydroshikimate (3-DHS) by purified E. coli and J. regia SDH when shikimic acid (SA) or 3-DHS were used as substrates and NADP(+) as cofactor. Finally, we show that purified E. coli and J. regia SDH produced GA in vitro.

Neuromyelitis optica immunoglobulins as a marker of disease activity and response to therapy in patients with neuromyelitis optica

Objective

To determine whether neuromyelitis optica (NMO) immunoglobulin (IgG) antibody status in NMO/Devic’s disease patients followed prospectively is persistent or can change relative to the clinical status and/or response to therapy.

Design

A cross-sectional group of patients with NMO, relapsing extensive longitudinal transverse myelitis (RLETM) or optico-spinal multiple sclerosis (OSMS) were evaluated for the presence of NMO IgG antibodies. Repeated evaluation was made in all NMO/RLETM patients and in a subgroup of OSMS patients.

Setting

Baird Multiple Sclerosis Center, Buffalo, New York, an academic multiple sclerosis center.

Results

Out of a consecutive cohort of 38 patients evaluated for the presence of NMO IgG, 12 had NMO and 26 had OSMS. Five of the 12 NMO/RLETM patients were NMO IgG positive at the time of their initial evaluation. Four of these patients were repeatedly tested for NMO IgG: two of these became negative and two remained positive. One patient who was initially negative became positive during an acute event and again became negative during the stable disease phase following treatment. A positive test result was associated with active disease, whereas a negative NMO IgG result was consistently found in stable, long-term treated patients. None of the OSMS patients were positive for NMO IgG even during acute attacks.

Conclusions

NMO IgG antibodies are associated with active NMO/RLETM. A well-controlled stable disease usually under effective immunosuppressive therapy can transform the NMO IgG to a negative status. Repeated NMO IgG testing should be considered as a useful biological marker for monitoring NMO/RLETM disease and or response to therapy.

Reproductive potential of male Portan rats exposed to various levels of lead with regard to zinc status

The present study was designed to elucidate the mechanisms accounting for disruption of the normal function of the testis exposed to various levels of Pb. Three different doses of Pb (10, 50, 200mg Pb/kg body weight per d) were given orally to male Portan rats (groups 2, 3, 4). Zn (1mg Zn/kg body weight per d) was also given with Pb (50mg Pb/kg body weight per d) in group 5. Treatments continued for 3 months. Plasma luteinizing hormone and follicle-stimulating hormone concentrations were found to be decreased in Pb-exposed rats. This was in turn reflected in the appreciable decline in fertility status. In cell kinetic studies, significant declines in various cell populations (preleptotene, pachytene, young (step 7) spermatids and mature (step 19) spermatids) were seen. However, in group 5 after Zn supplementation, hormone levels, cell numbers and fertility status were found to be close to normal. It is concluded that Pb might act at maturation level to cause conspicuous degenerative changes in the testis; Zn supplementation protected against these effects.

Characterization of Ionically Bound Peroxidases from Apple(Mallus pumilus) Fruits

Ionically bound peroxidases (POD) were salt extracted from the pulp of four Indian apple varieties, i.e., Golden delicious HP, Golden delicious JK, Red delicious, and Royal delicious. They were precipitated with chilled ethanol. Thermal treatments of partially purified enzymes were given from 40-70 degrees C for 30 minutes. Golden delicious HP peroxidase showed thermostability at 60 degrees C, while three other peroxidases were observed at 50 degrees C. Phenolic compounds (i.e., caffeic acid, ferulic acids, p-coumaric acid, protocatechuic acid) and metal ions (i.e., Cu2+ and Fe2+) activated all apple peroxidases. However, Mn2+ inhibited the peroxidases from Golden delicious HP, Golden delicious JK, and Red delicious, and a substantial increase was observed in Royal delicious peroxidase. Mg2+ inhibited the peroxidases from Golden delicious HP and Red delicious, but marginal activation was reported in peroxidases from Golden delicious JK and Royal delicious. Zn2+ established stimulation in Golden delicious HP and Golden delicious JK peroxidases, but inhibition was observed in peroxidases in Red delicious and Royal delicious.. Methionine, proline, tryptophan, and valine stimulated all four apple peroxidases, but cysteine showed inhibition in Golden delicious JK.

Modulatory effects of Salmonella LAP-LPS on murine macrophages

PURPOSE

To study the modulatory effects of Salmonella lipid associated protein - lipopolysaccharides (LAP-LPS) on murine macrophages as the intracellular survival within the host macrophages is an important feature for a number of gram-negative pathogens like S. typhi.

METHODS

Macrophage functions were studied in two groups of mice immunized with either LPS or LAP-LPS.

RESULTS

Comparison of protective efficacy of mice preimmunized with LPS based preparations, against challenge infectious doses, showed higher protection in LAP-LPS complex immunized mice group as compared to the mice group immunized with LPS alone. Aggregation of S. typhi cells was lesser with intestinal mucus extracted from LAP-LPS immunized mice as compared to LPS immunized challenged group. A significant increase in the number of macrophages in LAP-LPS immunized mice was also observed in comparison to control and LPS immunized mice groups. Nitric oxide (NO) and superoxide dismutase (SOD) production were also more in macrophages derived from LAP-LPS immunized mice group. Phagocytic uptake studies showed that there was enhanced uptake of bacteria in the LAP-LPS immunized animals in comparison to LPS immunized and controls. Similar trend was observed in intracellular killing of bacteria by the macrophages.

CONCLUSIONS

The results indicated the involvement of protein moiety in LAP on modulation of effects of LPS on macrophages.

Influence of lead and zinc on rat male reproduction at 'biochemical and histopathological levels'

Sequential lead accumulation and biochemical and histopathological changes were observed in rat testis and epididymis after oral administration at varied doses of lead (10, 50 and 200 mg kg(-1) body wt.) for 3 months and also following the concomitant administration of lead with zinc (1 mg kg(-1) body wt. +50 mg Pb kg(-1) body wt.). Accumulation of lead in both testis and epididymis increased with dose. The concomitant administration of zinc reduced the lead levels. Similarly, dose-related changes were seen in the activities of the enzymes alkaline phosphatase and Na(+)-K(+)-ATPase, which decreased with increased dose of lead. A significant improvement in the activities of these enzymes was seen in the groups given both lead and zinc. Histologically, discernible changes were noticed only at higher doses (50 and 200 mg kg(-1) body wt.), which included disorganization and disruption of spermatogenesis with accumulation of immature cells in lumen of tubule. At higher doses of lead, complete arrest of spermatogenesis was seen and a significant decrease in germ cell layer population was evident. Even in epididymis, the histoarchitecture was disrupted only at higher doses of lead both in the caput and corpus regions. The changes included damage of basement membrane, disorganization of epithelium and vacuolization of cells. The tubules were found almost empty, indicating arrest of spermatogenesis. However, with concomitant administration of lead and zinc both testis and epididymis presented a near-normal picture, indicating the protective role of zinc. Hence, the data indicate that the protective effect of zinc on lead toxicity was mediated largely by significant competition between lead and zinc or due to reduction of the available binding sites.

The effect of zinc supplementation on the effects of lead on the rat testis

With increasing concerns about environmental pollution, the interaction of micronutrients with toxic metals is of great interest. The present study was designed to investigate testicular effects of lead following concomitant administration of zinc. Lead was administered orally as lead acetate (50 mg/kg b.w.) daily for 3 months to male Portan rats with or without zinc (1 mg/kg b.w. as zinc sulphate). The control group was given the same volume of distilled water. Endpoints included lead concentration in various body organs as well as in the reproductive system, including testicular subfractions; the testicular enzymes superoxide dismutase (SOD) and catalase; the marker enzyme delta-aminolevulinic acid dehydratase (delta-ALAD); and testicular histoarchitecture. The concentrations of lead in bone, kidney, prostate, testis, liver, epididymis, spleen, seminal vesicles, and blood were significantly higher in lead-treated rats. Lead deposition was reduced in animals that received supplemental zinc. There was a 30% reduction in lead deposition in the testis when zinc was coadministered. At the subcellular level, there was differential accumulation of lead; the nucleus preferentially took up the metal after lead treatment alone, while zinc coadministration shifted lead accumulation to the mitochondria. A significant decrease in delta-ALAD and in SOD activity was seen in the testis with lead treatment. Coadministration of zinc prevented these decreases, at least partially. Zinc coadministration did not prevent the inhibition of catalase observed with lead treatment. Histologically, the alterations in the testis with lead treatment alone were more pronounced compared to animals in which zinc was supplemented. Improvement in the inhibition of delta-ALAD and in the ubiquitous cellular enzyme SOD suggests less testicular tissue damage due to detoxification of free radicals. In conclusion, zinc supplementation ameliorates lead-induced testicular damage both at the cellular and subcellular level. The protective effect may be due to differential distribution of lead, either because of competition between lead and zinc or displacement of lead by zinc.

Not clients, not consumers and definitely not maternants

OBJECTIVE

To determine appropriate terminology for addressing women in pregnancy.

DESIGN

100 women (aged 15-50) were asked to fill in a questionnaire using one of the six choices provided for addressing women in pregnancy.

SETTING

Antenatal clinic of a teaching hospital.

RESULTS

Preferences vary according to context but simple terms like mother-to-be and pregnant women were more popular than client, consumer and maternant.

CONCLUSION

No single terminology for addressing women in pregnancy wins all round approval but simple softer terms like Mother-to-be please a vast majority.

Is transcutaneous electrical nerve stimulation of any value during cervical laser treatment?

OBJECTIVE

To assess the value of transcutaneous electrical nerve stimulation (TENS) during cervical laser therapy.

DESIGN

Randomized three arm controlled clinical trial comparing (i) TENS, (ii) local anaesthetic and (iii) TENS plus local anaesthetic (direct infiltration of 2% lignocaine and 0.03 iu/ml octopressin).

SETTING

Colposcopy Unit adapted to run randomized trials.

SUBJECTS

100 women with CIN and no previous experience of cervical surgery.

MAIN OUTCOME MEASURE

Visual linear analogue pain scores.

RESULTS

The median pain score associated with TENS was greater than the score associated with local anaesthesia (23% compared with 17%; P = 0.1). Combining TENS with local anaesthesia did not further reduce pain scores.

CONCLUSION

Although there was considerable consumer satisfaction with TENS it provided no additional pain relieving effect in addition to direct infiltration of lignocaine and it is inferior to lignocaine alone. We are unable to advocate the use of TENS for laser treatment of the cervix.