The Enemy Within: Human Cytomegalovirus. Juliet V. Spencer University of San Francisco

Transcription

1 The Enemy Within: Human Cytomegalovirus Juliet V. Spencer University of San Francisco NCASM Spring Meeting March 8, 2014

2 Herpes is all around us Human Herpesviruses Clinical Presentation Herpes simplex virus 1 cold sores Herpes simplex virus 2 genital herpes Varicella- Zoster Virus chicken pox/shingles Epstein- Barr Virus mononucleosis Human Cytomegalovirus rash, birth defects Human Herpesvirus 6 roseola infantum Human Herpesvirus 7 roseola infantum Human Herpesvirus 8 Kaposi s sarcoma Common Features: 1. Virus structure 2. Lifelong latent infection

3 Human Cytomegalovirus (HCMV) Highly species specific Within host infects wide range of cells Epithelial cells, endothelial cells, fibroblasts, myeloid cells. Inclusions (owl eyes) Cytomegaly (giant cells)

4 HCMV Infection & Latency Transmission: mucosa 50-90% seropositive in US Mild infection Latency in bone marrow Virus stays in body forever! Periodic reactivation, shedding

5 Health Impact of HCMV Transplant recipients - BIG problem Most donors are seropositive! The troll of transplantation (Balfour 1979) Direct effects: pneumonitis, hepatitis, retinitis, death Indirect effects: graft rejection, vasculopathy, diabetes, opportunistic infections Ganciclovir has improved outcome, but..resistance!! Also other immune compromised populations - AIDS patients

6 Health Impact of HCMV Pregnant woman VERY BIG problem 30,000 blueberry muffin babies/year 20% suffer long term defects deafness, mental retardation, etc. Mostly seronegative women, but superinfection! Vaccine desperately needed

7 Health Impact of HCMV The Enemy Within Long term chronic infection + declining immune function = Cardiovascular disease

8 Health Impact of HCMV The Enemy Within Long term chronic infection + declining immune function = CANCER ONCOMODULATION HCMV promotes tumor progression

9 HCMV and Cancer - Glioblastoma Tumor Invasive Normal Cobbs et al, 2002 HCMV proteins and DNA detected in malignant gliomas Dziurzynski et al., 2011 Consensus on the role of human cytomegalovirus in cancer IE1 staining from Dziurzynski et al., 2011 Hadaczek et al., 2013 Cidofovir has anti- tumor activity for glioblastoma

10 HCMV and Breast Cancer? Yes! Taher et al, 2013 HCMV present in 100% of breast cancer specimens examined It s complicated No! Utera- Barillas et al., 2013 No association between HCMV and breast cancer progression 4 of 47 samples HCMV+

11 HCMV: Master Manipulator 230 kb genome, 167 genes >50% target host processes Especially immune responses * Cytokines & chemokines * Alter cellular communications * UL111A gene encodes cmvil- 10

12 A Tale of Two Cytokines Human version: IL- 10 * Normal human cytokine * Helps end immune response * Anti- inflammatory effects Viral version: cmvil- 10 * Mimics human IL- 10 effects * Virus shuts off immune response!

13 Anything you can do I can do better cmvil- 10 / human IL % amino acid identity cmvil- 10 cmvil- 10 High affinity binding to IL- 10R JAK/Stat signaling Dampen immune response Possible role in cancer?

14 IL- 10 and Cancer Elevated IL- 10 = poor prognosis (Mahipal et al, 2011, Llanes- Fernandez et al, 2006) IL- 10 inhibits apoptosis, promotes invasion (Zeng et al, 2009, Zheng et al, 2007) Stat 3 activation increased metastatic potential (Zhang et al 2010, Yu et al, 2009)

15 Could cmvil- 10 act on breast cancer cells in a paracrine manner to promote a more invasive phenotype? cmvil- 10 IL- 10R Stat3 Stat3 Tx Cell Proliferation Inhibition of Apoptosis Migration/Chemotaxis Altered Gene Expression

16 Human breast cancer cells express IL- 10R ESTROGEN RECEPTOR (ER) EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR) INTERLEUKIN- 10 RECEPTOR (IL- 10R) MDA- MB MCF MDA- MB- 231 IL- 10R IL- 10R Cell Count Fluorescence intensity 2 o only

17 And are not infected with HCMV

18 Time (min) IL- 10R distribution following treatment with cmvil RelaGve Fluorescence Units 180

19 cmvil- 10 triggers Stat3 activation

20 cmvil- 10 stimulates cell proliferation * p < 0.01

21 cmvil- 10 promotes cell survival

22 Enhanced migration to EGF with cmvil- 10 Relative Light Units Control cmvil- 10 Relative Light Units Control EGF EGF (ng/ml)

23 cmvil- 10 induces changes in gene expression Tumor Metastasis Array

24 cmvil- 10 induces changes in cell adhesion genes Cell Adhesion Panel Metastasis suppressor protein 1 Tumor suppressor Cell- cell junctions

25 cmvil- 10 induces changes in MMP genes Extracellular Matrix Panel MMP3 (pg/ml) cmvil- 10 (ng/ml) Matrix metalloproteinase 3 Stromelysin Degrades collagen Activates other MMPs

26 ü Clean up on IL- 10! cmvil- 10 promotes an invasive phenotype * Stat3 activation * Increased cell proliferation * Protection from apoptosis * Increased migration * Altered gene expression ü ü ü

27 What does this mean? * cmvil- 10 promotes cancer progression * Cells have more invasive potential Long term implications: * Should cancer patients be screened for CMV? * Should they be treated with chemotherapy + anti- CMV therapeutics?

28 Where do we go from here? Future directions * Would cmvil- 10 truly promote metastasis in vivo? * Can cmvil- 10 be detected in human serum? * Do levels correlate with disease severity in cancer patients?

29 Final thoughts Is HCMV really the enemy? Some say no key to HIV vaccine! * Long- lived, non- pathogenic * Induces broad T cell responses * Big coding capacity * Ideal vaccine vector * Successful protection of monkeys from SIV! Picker et al., 2012 Ann Rev Med 63:95 Hansen et al., 2011 Nature 473:523 Hansen et al., 2013 Nature 502:100

30 Acknowledgements Cendy Valle Oseguera Robin Bishop Carolyn Tu Vivian Young Karl Banta Amanda Moules Jeff Oda Katie Arnolds HERPESVIRUS RESEARCH LAB National Institutes of Health Lily Drake Cancer Fund USF Faculty Development Fund The Fletcher Jones Foundation