Alternative splicing of its 5'-UTR limits CD20 mRNA translation and enables resistance to CD20-directed immunotherapies

Aberrant skipping of coding exons in CD19 and CD22 compromises the response to immunotherapy in B-cell malignancies. Here, we showed that the MS4A1 gene encoding human CD20 also produces several messenger RNA (mRNA) isoforms with distinct 5' untranslated regions. Four variants (V1-4) were detected using RNA sequencing (RNA-seq) at distinct stages of normal B-cell differentiation and B-lymphoid malignancies, with V1 and V3 being the most abundant. During B-cell activation and Epstein-Barr virus infection, redirection of splicing from V1 to V3 coincided with increased CD20 positivity. Similarly, in diffuse large B-cell lymphoma, only V3, but not V1, correlated with CD20 protein levels, suggesting that V1 might be translation-deficient. Indeed, the longer V1 isoform contained upstream open reading frames and a stem-loop structure, which cooperatively inhibited polysome recruitment. By modulating CD20 isoforms with splice-switching morpholino oligomers, we enhanced CD20 expression and anti-CD20 antibody rituximab-mediated cytotoxicity in a panel of B-cell lines. Furthermore, reconstitution of CD20-knockout cells with V3 mRNA led to the recovery of CD20 positivity, whereas V1-reconstituted cells had undetectable levels of CD20 protein. Surprisingly, in vitro CD20-directed chimeric antigen receptor T cells were able to kill both V3- and V1-expressing cells, but the bispecific T-cell engager mosunetuzumab was only effective against V3-expressing cells. To determine whether CD20 splicing is involved in immunotherapy resistance, we performed RNA-seq on 4 postmosunetuzumab follicular lymphoma relapses and discovered that in 2 of them, the downregulation of CD20 was accompanied by a V3-to-V1 shift. Thus, splicing-mediated mechanisms of epitope loss extend to CD20-directed immunotherapies.

Alternative splicing of its 5'-UTR limits CD20 mRNA translation and enables resistance to CD20-directed immunotherapies

Aberrant skipping of coding exons in CD19 and CD22 compromises responses to immunotherapy for B-cell malignancies. Here, we show that the MS4A1 gene encoding human CD20 also produces several mRNA isoforms with distinct 5' untranslated regions (5'-UTR). Four variants (V1-4) were detectable by RNA-seq in distinct stages of normal B-cell differentiation and B-lymphoid malignancies, with V1 and V3 being the most abundant by far. During B-cell activation and Epstein-Barr virus infection, redirection of splicing from V1 to V3 coincided with increased CD20 positivity. Similarly, in diffuse large B-cell lymphoma only V3, but not V1, correlated with CD20 protein levels, suggesting that V1 might be translation-deficient. Indeed, the longer V1 isoform was found to contain upstream open reading frames (uORFs) and a stem-loop structure, which cooperatively inhibited polysome recruitment. By modulating CD20 isoforms with splice-switching Morpholino oligomers, we enhanced CD20 expression and anti-CD20 antibody rituximab-mediated cytotoxicity in a panel of B-cell lines. Furthermore, reconstitution of CD20-knockout cells with V3 mRNA led to the recovery of CD20 positivity, while V1-reconstituted cells had undetectable levels of CD20 protein. Surprisingly, in vitro CD20-directed CAR T cells were able to kill both V3- and V1-expressing cells, but the bispecific T cell engager mosunetuzumab was only effective against V3-expressing cells. To determine whether CD20 splicing is involved in immunotherapy resistance, we performed RNA-seq on four post-mosunetuzumab follicular lymphoma relapses and discovered that in two of them downregulation of CD20 was accompanied by the V3-to-V1 shift. Thus, splicing-mediated mechanisms of epitope loss extend to CD20-directed immunotherapies.

Key Points

In normal & malignant human B cells, CD20 mRNA is alternatively spliced into four 5'-UTR isoforms, some of which are translation-deficient.The balance between translation-deficient and -competent isoforms modulates CD20 protein levels & responses to CD20-directed immunotherapies.

Explanation of Novelty

We discovered that in normal and malignant B-cells, CD20 mRNA is alternatively spliced to generate four distinct 5'-UTRs, including the longer translation-deficient V1 variant. Cells predominantly expressing V1 were still sensitive to CD20-targeting chimeric antigen receptor T-cells. However, they were resistant to the bispecific anti-CD3/CD20 antibody mosunetuzumab, and the shift to V1 were observed in CD20-negative post-mosunetuzumab relapses of follicular lymphoma.

Elevated iNOS and 3'-nitrotyrosine in Kaposi's Sarcoma tumors and mouse model

Kaposi's Sarcoma (KS) is a heterogenous, multifocal vascular malignancy caused by the human herpesvirus 8 (HHV8), also known as Kaposi's Sarcoma-Associated Herpesvirus (KSHV). Here, we show that KS lesions express iNOS/NOS2 broadly throughout KS lesions, with enrichment in LANA positive spindle cells. The iNOS byproduct 3-nitrotyrosine is also enriched in LANA positive tumor cells and colocalizes with a fraction of LANA-nuclear bodies. We show that iNOS is highly expressed in the L1T3/mSLK tumor model of KS. iNOS expression correlated with KSHV lytic cycle gene expression, which was elevated in late-stage tumors (>4 weeks) but to a lesser degree in early stage (1 week) xenografts. Further, we show that L1T3/mSLK tumor growth is sensitive to an inhibitor of nitric oxide, L-NMMA. L-NMMA treatment reduced KSHV gene expression and perturbed cellular gene pathways relating to oxidative phosphorylation and mitochondrial dysfunction. These finding suggest that iNOS is expressed in KSHV infected endothelial-transformed tumor cells in KS, that iNOS expression depends on tumor microenvironment stress conditions, and that iNOS enzymatic activity contributes to KS tumor growth.

Unstable EBV latency drives inflammation in multiple sclerosis patient derived spontaneous B cells

Epidemiological studies have demonstrated that Epstein-Barr virus (EBV) is a known etiologic risk factor, and perhaps prerequisite, for the development of MS. EBV establishes life-long latent infection in a subpopulation of memory B cells. Although the role of memory B cells in the pathobiology of MS is well established, studies characterizing EBV-associated mechanisms of B cell inflammation and disease pathogenesis in EBV (+) B cells from MS patients are limited. Accordingly, we analyzed spontaneous lymphoblastoid cell lines (SLCLs) from multiple sclerosis patients and healthy controls to study host-virus interactions in B cells, in the context of an individual's endogenous EBV. We identify differences in EBV gene expression and regulation of both viral and cellular genes in SLCLs. Our data suggest that EBV latency is dysregulated in MS SLCLs with increased lytic gene expression observed in MS patient B cells, especially those generated from samples obtained during "active" disease. Moreover, we show increased inflammatory gene expression and cytokine production in MS patient SLCLs and demonstrate that tenofovir alafenamide, an antiviral that targets EBV replication, decreases EBV viral loads, EBV lytic gene expression, and EBV-mediated inflammation in both SLCLs and in a mixed lymphocyte assay. Collectively, these data suggest that dysregulation of EBV latency in MS drives a pro-inflammatory, pathogenic phenotype in memory B cells and that this response can be attenuated by suppressing EBV lytic activation. This study provides further support for the development of antiviral agents that target EBV-infection for use in MS.

Proceedings of the 7th Biannual International Symposium on Nasopharyngeal Carcinoma 2015

A1 Hope and despair in the current treatment of nasopharyngeal cancer

IB Tan

I1 NPC international incidence and risk factors

Ellen T Chang

I2 Familial nasopharyngeal carcinoma and the use of biomarkers

Chien-Jen Chen, Wan-Lun Hsu, Yin-Chu Chien

I3 Genetic susceptibility risk factors for sporadic and familial NPC: recent findings

Allan Hildesheim

I5 Genetic and environmental risk factors for nasopharyngeal cancer in Southeast Asia

James D McKay, Valerie Gaborieau, Mohamed Arifin Bin Kaderi, Dewajani Purnomosari, Catherine Voegele, Florence LeCalvez-Kelm, Graham Byrnes, Paul Brennan, Beena Devi

I6 Characterization of the NPC methylome identifies aberrant epigenetic disruption of key signaling pathways and EBV-induced gene methylation

Li L, Zhang Y, Fan Y, Sun K, Du Z, Sun H, Chan AT, Tsao SW, Zeng YX, Tao Q

I7 Tumor exosomes and translational research in NPC

Pierre Busson, Claire Lhuillier, Olivier Morales, Dhafer Mrizak, Aurore Gelin, Nikiforos Kapetanakis, Nadira Delhem

I8 Host manipulations of the Epstein-Barr virus EBNA1 protein

Sheila Mansouri, Jennifer Cao, Anup Vaidya, and Lori Frappier

I9 Somatic genetic changes in EBV-associated nasopharyngeal carcinoma

Lo Kwok Wai

I10 Preliminary screening results for nasopharyngeal carcinoma with ELISA-based EBV antibodies in Southern China

Sui-Hong Chen, Jin-lin Du, Ming-Fang Ji, Qi-Hong Huang, Qing Liu, Su-Mei Cao

I11 EBV array platform to screen for EBV antibodies associated with NPC and other EBV-associated disorders

Denise L. Doolan, Anna Coghill, Jason Mulvenna, Carla Proietti, Lea Lekieffre, Jeffrey Bethony, and Allan Hildesheim

I12 The nasopharyngeal carcinoma awareness program in Indonesia

Renske Fles, Sagung Rai Indrasari, Camelia Herdini, Santi Martini, Atoillah Isfandiari, Achmad Rhomdoni, Marlinda Adham, Ika Mayangsari, Erik van Werkhoven, Maarten Wildeman, Bambang Hariwiyanto, Bambang Hermani, Widodo Ario Kentjono, Sofia Mubarika Haryana, Marjanka Schmidt, IB Tan

I13 Current advances and future direction in nasopharyngeal cancer management

Brian O’Sullivan

I14 Management of juvenile nasopharyngeal cancer

Enis Ozyar

I15 Global pattern of nasopharyngeal cancer: correlation of outcome with access to radiotherapy

Anne WM Lee

I16 The predictive/prognostic biomarker for nasopharyngeal carcinoma

Mu-Sheng Zeng

I17 Effect of HLA and KIR polymorphism on NPC risk

Xiaojiang Gao, Minzhong Tang, Pat Martin, Yi Zeng, Mary Carrington

I18 Exploring the Association between Potentially Neutralizing Antibodies against EBV Infection and Nasopharyngeal Carcinoma

Anna E Coghill, Wei Bu, Hanh Nguyen, Wan-Lun Hsu, Kelly J Yu, Pei-Jen Lou, Cheng-Ping Wang, Chien-Jen Chen, Allan Hildesheim, Jeffrey I Cohen

I19 Advances in MR imaging in NPC

Ann D King

O1 Epstein-Barr virus seromarkers and risk of nasopharyngeal carcinoma: the gene-environment interaction study on nasopharyngeal carcinoma in Taiwan

Yin-Chu Chien, Wan-Lun Hsu, Kelly J Yu, Tseng-Cheng Chen, Ching-Yuan Lin, Yung-An Tsou, Yi-Shing Leu, Li-Jen Laio, Yen-Liang Chang, Cheng-Ping Wang, Chun-Hun Hua, Ming-Shiang Wu, Chu-Hsing Kate Hsiao, Jehn-Chuan Lee, Ming-Hsui Tsai, Skye Hung-Chun Cheng, Pei-Jen Lou, Allan Hildesheim, Chien-Jen Chen

O2 Familial tendency and environmental co-factors of nasopharyngeal carcinoma: the gene-environment interaction study on nasopharyngeal carcinoma in Taiwan

Wan-Lun Hsu, Kelly J Yu, Yin-Chu Chien, Tseng-Cheng Chen, Ching-Yuan Lin, Yung-An Tsou, Yi-Shing Leu, Li-Jen Liao, Yen-Liang Chang, Tsung-Lin Yang, Chun-Hun Hua, Ming-ShiangWu, Chu-Hsing Kate Hsiao, Jehn-ChuanLee, Ming-Hsui Tsai, Skye Hung-Chun Cheng, Jenq-Yuh Ko, Allan Hildesheim, Chien-Jen Chen

O3 The genetic susceptibility and prognostic role of TERT-CLPTM1L and genes in DNA damage pathways in NPC

Josephine Mun Yee Ko, Wei Dai, Dora Kwong, Wai Tong Ng, Anne Lee, Roger Kai Cheong Ngan, Chun Chung Yau, Stewart Tung, Maria Li Lung

O4 Long term effects of NPC screening

Mingfang Ji, Wei Sheng, Mun Hon Ng, Weimin Cheng, Xia Yu, Biaohua Wu, Kuangrong Wei, Jun Zhan, Yi Xin Zeng, Su Mei Cao, Ningshao Xia, Yong Yuan

O5 Risk prediction of nasopharyngeal carcinoma by detecting host genetic and Epstein-Barr virus variation in saliva

Qian Cui, Miao Xu, Jin-Xin Bei, Yi-Xin Zeng

O6 Patterns of care study in Turkish nasopharyngeal cancer patients (NAZOTURK): A Turkish Radiation Oncology Association Head and Neck Cancer Working Group Study

B Şahin, A Dizman, M Esassolak, A Saran İkizler, HC Yıldırım, M Çaloğlu, B Atalar, F Akman, C Demiroz, BM Atasoy, E Canyilmaz, S Igdem, G Ugurluer, T Kütük, M Akmansoy, E Ozyar

O7 Long term outcome of intensity modulated radiotherapy in nasopharyngeal carcinoma in National Cancer Centre Singapore

Kiattisa Sommat, Fu Qiang Wang, Li-Lian Kwok, Terence Tan, Kam Weng Fong, Yoke Lim Soong, Shie Lee Cheah, Joseph Wee

O8 International phase II randomized study on the addition of docetaxel to the combination of cisplatin and 5-fluorouracil in the induction treatment for nasopharyngeal carcinoma in children and adolescents

M Casanova, E Özyar, C Patte, D Orbach, A Ferrari, VF Cristine, H Errihani, J Pan, L Zhang, S Liji, K Grzegorzewski, L Gore, A Varan

O9 Prognostic impact of metastatic status in patients with nasopharyngeal carcinoma

Susanna Hilda Hutajulu, Guntara Khuzairi, Camelia Herdini, Henry Kusumo, Mardiah Suci Hardianti, Kartika Widayati Taroeno-Hariadi, Ibnu Purwanto, Johan Kurnianda

O10 Development of small molecule inhibitors of latent Epstein-Barr virus infection for the treatment of nasopharyngeal carcinoma

Troy E. Messick, Kimberly Malecka, Lois Tolvinski, Samantha Soldan, Julianna Deakyne, Hui Song, Antonio van den Heuvel, Baiwei Gu, Joel Cassel, Mark McDonnell, Garry R Smith, Venkata Velvadapu, Haiyan Bian, Yan Zhang, Marianne Carlsen, Shuai Chen, Alastair Donald, Christian Lemmen, Allen B Reitz, Paul M Lieberman

O11 Therapeutic targeting of cancer stem-like cells using a Wnt modulator, ICG-001, enhances the treatment outcome of EBV-positive nasopharyngeal carcinoma

King Chi Chan, Lai Sheung Chan, Kwok Wai Lo, Timothy Tak Chun Yip, Roger Kai Cheong Ngan, Michael Kahn, Maria Li Lung, Nai Ki Mak

O12 Role of micro-RNA in NPC biology

Fei-Fei Liu

O13 Expansion of EBNA1- and LMP2-specific effector T lymphocytes from patients with nasopharyngeal carcinoma without enhancement of regulatory T cells

Wafa Khaali; Juliette Thariat; Laurence Fantin; Flavia Spirito; Meriem Khyatti; El Khalil Ben Driss; Sylvain Olivero; Janet Maryanski; Alain Doglio

O14 The experience of patients’ life after amifostine radiotherapy treatment (ART) for nasopharyngeal carcinoma (NPC)

Mengxue Xia, Yunfei Xia, Hui Chang, Rachel Shaw

O15 Analysis of mitochondrial DNA mutation in latent membrane protein-1 positive nasopharyngeal carcinoma

Pudji Rahaju

O16 Factors influencing treatment adherence of nasopharyngeal cancer and the clinical outcomes: a hospital-based study

Mardiah Suci Hardianti, Sindhu Wisesa, Kartika Widayati Taroeno-Harijadi, Ibnu Purwanto, Bambang Hariwiyanto, Wigati Dhamiyati, Johan Kurnianda

O17 Chromosomal breaks mediated by bile acid-induced apoptosis in nasopharyngeal epithelial cells: in relation to matrix association region/scaffold attachment region

Sang-Nee Tan, Sai-Peng Sim

O18 Expression of p53 (wild type) on nasopharyngeal carcinoma stem cell that resistant to radiotherapy

Muhtarum Yusuf, Ahmad C Romdhoni, Widodo Ario K, Fedik Abdul Rantam

O19 Mathematical model of nasopharyngeal carcinoma in cellular level

Sugiyanto, Lina Aryati, Fajar Adi-Kusumo, Mardiah Suci Hardianti

O20 Differential expression of microRNA-21 on nasopharyngeal carcinoma plasma patient

SY Bintoro, R Oktriani, C. Herawati, A Surono, Sofia M. Haryana

O21 Therapeutic targeting of an oncogenic fibroblast growth factor-FGF19, which promotes proliferation and induces EMT of carcinoma cells through activating ERK and AKT signaling

L. Zhong, L. Li, B. B. Ma, A. T. Chan, Q. Tao

O22 Resist nasopharyngeal carcinoma (NPC): next generation T cells for the adoptive immunotherapy of NPC

M. Kalra, M. Ngo, S. Perna, A. Leen, N. Lapteva, C. M. Rooney, S. Gottschalk

O23 The correlation of heat shock protein 70 expressions and staging of nasopharyngeal carcinoma

Elida Mustikaningtyas, Sri Herawati, Achmad C Romdhoni

O24 Epstein-Barr virus serological profiles of nasopharyngeal carcinoma - A tribute to Werner Henle

Mingfang Ji, YaruiXu, Weimin Cheng, ShengxiangGe, Fugui Li, M. H. Ng

O25 Targeting the apoptosis pathway using combination TLR3 agonist with anti-survivin molecule (YM-155) in nasopharyngeal carcinoma

Louise SY Tan, Benjamin Wong, CM Lim

O26 The resistance mechanism of nasopharyngeal cancer stem cells to cisplatin through expression of CD44, Hsp70, p53 (wild type), Oct-4, and ß-catenin encoded-genes

Achmad C Romdhoni, Fedik A. Rantam, Widodo Ario Kentjono

P1 Prevalence of nasopharyngeal carcinoma patients at Departement of Otorhinolaringology-Head and Neck Surgery, Dr. Hasan Sadikin general hospital, Bandung, Indonesia in 2010-2014

Deasy Z Madani, Nur Akbar, Agung Dinasti Permana

P2 Case report on pediatric nasopharyngeal carcinoma at Dr. Sardjito Hospital, Yogyakarta

Camelia Herdini, Sagung Rai Indrasari, Jajah Fachiroh, Dwi Hartati, T. Baning Rahayudjati

P3 Report on loco regionally advanced nasopharyngeal cancer patients treated with induction chemotherapy followed by concurrent chemo-radiation therapy

Iswandi Darwis, Susanna Hilda Hutajulu, Bambang Hariwiyanto, Wigati Dhamiyati, Ibnu Purwanto, Kartika Widayati Taroeno-Hariadi, Johan Kurnianda

P4 Sex and age differences in the survival of patients with nasopharyngeal carcinoma

Sindhu Wisesa, Mardiah Suci Hardianti, Susanna Hilda Hutajulu, Kartika Widayati Taroeno-Harijadi, Ibnu Purwanto, Camelia Herdini, Wigati Dhamiyati, Johan Kurnianda

P5 Impact of delayed diagnosis and delayed therapy in the treatment outcome of patients with nasopharyngeal carcinoma

Khoirul Anwar, Susanna Hilda Hutajulu, Sagung Rai Indrasari, Sri Retna Dwidanarti, Ibnu Purwanto, Kartika Widayati Taroeno-Hariadi, Johan Kurnianda

P6 Anaysis of pretreatment anemia in nasopharyngeal cancer patients undergoing neoadjuvant therapy

Dominicus Wendhy Pramana, Susanna Hilda Hutajulu, Bambang Hariwiyanto, Wigati Dhamiyati, Ibnu Purwanto, Kartika Widayati Taroeno-Hariadi, Johan Kurnianda

P7 Results of treatment with neoadjuvant cisplatin-5FU in locally advanced nasopharyngeal carcinoma: a local experience

Diah Ari Safitri, Susanna Hilda Hutajulu, Camelia Herdini, Sri Retna Dwi Danarti, Ibnu Purwanto, Kartika Widayati Taroeno-Hariadi, Johan Kurnianda

P8 Geriatrics with nasopharyngeal cancer

Suryo A Taroeno, Sindhu Wisesa, Kartika Widayati Taroeno-Hariadi, Ibnu Purwanto, Bambang Hariwiyanto, Wigati Dhamiyati, Johan Kurnianda

P9 Correlation of lymphocyte to monocyte and neutrophil to lymphocyte ratio to the response of cisplatin chemoradiotheraphy in locally advance nasopharyngeal carcinoma

I. Wijaya, A. Oehadian, D. Prasetya

P10 Prediction of nasopharyngeal carcinoma risk by Epstein-Barr virus seromarkers and environmental co-factors: the gene-environment interaction study on nasopharyngeal carcinoma in Taiwan

Wan-Lun Hsu, Yin-Chu Chien, Kelly J Yu, Cheng-Ping Wang, Ching-Yuan Lin, Yung-An Tsou, Yi-Shing Leu, Li-Jen Liao, Yen-Liang Chang^191,192, Jenq-Yuh Ko, Chun-Hun Hua, Ming-Shiang Wu, Chu-Hsing Kate Hsiao, Jehn-Chuan Lee, Ming-Hsui Tsai, Skye Hung-Chun Cheng, Pei-Jen Lou, Allan Hildesheim, Chien-Jen Chen

P11 Non-viral risk factors for nasopharyngeal carcinoma in West Sumatra, Indonesia

Sukri Rahman, Bestari J. Budiman, Novialdi, Rahmadona, Dewi Yuri Lestari

P12 New prototype Vidas EBV IgA quick: performance on Chinese and Moroccan populations

C. Yin, A. Foussadier, E. Blein, C. Chen, N. Bournet Ammour, M. Khiatti, S. Cao

P13 The expression of EBV-LMP1 and VEGF as predictors and plasma EBV-DNA levels as early marker of distant metastasis after therapy in nasopharyngeal cancer

Dewi Syafriyetti Soeis Marzaini

P14 Characteristics and factors influencing subjects refusal for blood samples retrieval: lesson from NPC case control study in Yogyakarta – Indonesia

Dwi Hartati, Baning Rahayujati, Camelia Herdini, Jajah Fachiroh

P15 Expression of microRNA BART-7-3p and mRNA PTEN on blood plasma of patients with nasopharyngeal carcinoma

L. Gunawan, S. Mubarika Haryana, A. Surono, C. Herawati

P16 IgA response to native early antigen (IgA-EAext) of Epstein-Barr virus (EBV) in healthy population and nasopharyngeal carcinoma (NPC) patients: the potential for diagnosis and screening tools

Michael Hartono, Jajah Fachiroh, Umi Intansari, Dewi Kartikawati Paramita

P17 IgA responses against Epstein-Barr Virus Early Antigen (EBV-EA) peptides as potential candidates of nasopharyngeal carcinoma detection marker

Akmal Akbar, Jajah Fachiroh, Dewi Kartikawati Paramita

P18 Association between smoking habit and IgA-EBV titer among healthy individuals in Yogyakarta, Indonesia

Benny Hermawan, T Baning Rahayudjati, Dewi K Paramita, Jajah Fachiroh

P19 Epstein-Barr virus IgA titer comparison of healthy non-family individuals and healthy first degree family of NPV patients

Gabriella Argy, Jajah Fachiroh, Dewi Kartikawati Paramita, Susanna Hilda Hutajulu

P20 Identification of EBV Early Antigen (EA) derived peptides for NPC diagnosis

Theodora Caroline Sihotang, Jajah Fachiroh, Umi Intansari, Dewi Kartikawati Paramita

P21 Host-pathogen study: relative expression of mRNA BRLF1 Epstein-Barr virus as a potential biomarker for tumor progressivity and polymorphisms of TCRBC and TCRGC2 host genes related to genetic susceptibility on nasopharyngeal carcinoma

Daniel Joko Wahyono, Purnomo Soeharso, Dwi Anita Suryandari, Lisnawati, Zanil Musa, Bambang Hermani

P22 In vitro efficacy of silvestrol and episilvestrol, isolated from Borneo, on nasopharyngeal carcinoma, a major cancer in Borneo

Maelinda Daker, Yeo Jiun Tzen, Norhasimah Bakar, Asma’ Saiyidatina Aishah Abdul Rahman, Munirah Ahmad, Yeo Tiong Chia, Alan Khoo Soo Beng

P23 The expression of mir-141 in patients with nasopharyngeal cancer

Widyandani Sasikirana, Tirta Wardana, Muhammad Radifar, Cita Herawati, Agus Surono, Sofia Mubarika Haryana

Phototherapeutic effects in hamsters with heart disease

In previous experiments we have shown that hamsters with inherited heart disease--cardiomyopathic hamsters (CMHs)--live longer if they spend their lives in an environment devoid of time cues. The purpose of this experiment was to test the several hypotheses by which life in constant light could extend life in CMHs. To do this, CMHs were allowed to spend their lives in one of six different lighting conditions: constant light, LD 12:12, LD 23:1, LD 1:23, LD 1:23.2, and LD 1:23.6. The only schedule to produce a significant extension of life was LD 1:23.6; in contrast to LD 1:23.2, this schedule is photostimulatory. Of the hypotheses tested to evaluate the life-enhancing effects of constant light, support was found for only the one stating that non-24-h LD regimens are health enhancing. Although some evidence was found relating testicular size to life span, dissociations between these variables indicate that testicular function does not play an overriding role in modulating the phototherapeutic effects.

Regulatory function of glucose and insulin on high-density lipoprotein cholesterol in normolipidemic subjects

A decreased plasma concentration of high-density lipoprotein (HDL) cholesterol is associated with a higher incidence of coronary artery disease in populations. Therefore, there is intense investigation into the mechanisms responsible for the regulation of HDL cholesterol concentration in plasma. Insulin has a potent effect on HDL cholesterol, but it is unclear whether this is mediated by the primary effect insulin has on plasma triglycerides (TG). In this study, the question of the relationship between glucose, insulin, and HDL cholesterol has been addressed by investigating a cohort of nondiabetic normolipidemic men living in the Venice, Italy, area. One hundred twenty-eight men aged 30 to 69 years were initially recruited. The following parameters were measured: fasting plasma cholesterol, TG, HDL cholesterol, glucose, and insulin. One hundred seventeen of these subjects underwent an oral glucose tolerance test (OGTT), and the glucose and insulin responses were assessed. The final statistical analysis was performed on 98 nondiabetic individuals with plasma lipid levels within the 75th percentile for cholesterol and TG concentrations of the general population of the same age. The insulin response was a positive independent variable for plasma TG (P < .005) and HDL cholesterol (P < .005). On the other hand, HDL cholesterol was negatively associated with plasma TG. This relationship remained significant (P < .0001) also after controlling for age, body mass index (BMI), and glucose- and insulin-related measurements. Consistent with these results, both a stepwise variable selection analysis and a stratification analysis of the data indicated that the plasma TG concentration is the major determinant of HDL cholesterol level.(ABSTRACT TRUNCATED AT 250 WORDS)

Persistent stress-induced sensitization of adrenocortical and startle responses

We assessed the functional adrenocortical and behavioral state of rats previously exposed to repeated stressor presentations. In Experiment 1, the whole-body startle response to threshold (91 dB) and suprathreshold (96 dB) stimuli was assessed in rats given 3 daily sessions (3DS) of 40, 2-mA tailshocks. The 3DS rats showed an exaggerated startle response to the threshold auditory stimulus 4 days poststressor compared to nonshocked controls (CON). An exaggerated startle response in stressed rats was not evident either 1 day or 10 days poststressor. In Experiment 2, adrenocortical sensitization and behavioral reactivity were assessed in rats exposed to 1 day (1DS) or 3 days of our stress regimen. Stressed rats exhibited elevated basal plasma corticosterone (CORT) levels 1 day poststressor which recovered by 9 days poststressor. Stressed rats also exhibited suppressed open-field activity 4 days poststressor. On the 10th day poststressor, rats were exposed to a single tailshock. The 1DS and 3DS rats showed both a sensitized and prolonged CORT response to stressor reexposure compared to control rats which received only the single tailshock. In addition, on the 11th day poststressor 3DS rats exhibited a moderate recapitulation of the elevated basal CORT levels seen after the initial stressor exposures. Thus, exposure to our stress regimen produces a chronic stress state in rats characterized by persistent behavioral and adrenocortical sensitization, as well as suppressed open-field activity and elevated basal CORT levels. Rats exhibiting a chronic stress state may be appropriate as a model for the study of stress-related psychophysiological illnesses, such as posttraumatic stress disorder.

Relationship of triglycerides and HDL cholesterol in hypertriglyceridemia

Hypoalphalipoproteinemia (plasma HDL-cholesterol concentration at or below 35 mg/dl as reported in the National Cholesterol Education Program Guidelines) is a well known risk factor for premature coronary artery disease (CAD). In hypertriglyceridemic patients, hypoalphalipoproteinemia is commonly believed to be linked to the derangement of triglyceride metabolism. In this study the occurrence of primary hypoalphalipoproteinemia has been investigated in a cohort of hypertriglyceridemic patients whose plasma triglyceride concentration had been normalized either through diet or diet plus drug treatment. Following the initial visit, 115 hypertriglyceridemic patients received dietary advice and returned for the second visit four months later. Diet reduced plasma triglycerides in all the patients. HDL-cholesterol increased in 76 patients whereas in the others, it remained unchanged or even decreased. Plasma triglyceride concentration was normalized (less than 200 mg/dl) in 54 patients by diet alone, but among these 11 remained hypoalphalipoproteinemics. Patients in whom, despite dietary restrictions, triglycerides exceeded 200 mg/dl, were considered for pharmacological treatment with Bezafibrate (300 mg t.i.d.) for 4 months. Thirty-nine concluded the study. Treatment significantly decreased plasma triglyceride concentration in all the subjects. Normalization was achieved in 32 patients. Four of them, however, remained hypoalphalipoproteinemic. These results indicate that a subgroup of hypertriglyceridemic patients remained hypoalphalipoproteinemic even after normalization of triglyceride levels. In these patients hypertriglyceridemia and hypoalphalipoproteinemia may occur as expression of two distinct primary metabolic defects.