microRNA biology and biomarkers – prostate cancer

microRNA biology and biomarkers – prostate cancer Stanley Liu, PhD, MD Clinician-­‐Scien4st Depts. of Medical Biophysics and Radia4on Oncology, University of Toronto Biology Stream, Sunnybrook Research Ins4tute OdeGe Cancer Centre, Sunnybrook Health Sciences Centre Radiotherapy •  Radia4on dose is delivered conformally to maximize dose to tumor while sparing surrounding 4ssue Clinical problems 1.  Tumor recurrence despite treatment with a ‘cura?ve’ dose of radia?on 2.  Personalizing treatment decisions -­‐ determining which pa?ents harbor high-­‐risk prostate cancer Targe?ng biology •  Our clinical gains from technological advances in radia?on treatment are plateauing •  Understanding and targe?ng biological processes is the next fron?er….. + Clinical problem 1 •  Pa?ent tumors can recur locally despite receiving a full course of radiotherapy. •  Recurrent tumors tend to be more aggressive and difficult to treat. •  Translates to worse outcomes for pa?ents. Radia?on resistant cancer model 2 Gy, 2 Gy …. similar to the clinic parental cells (PC3 prostate) radia?on resistant cells characterize cells Radia?on resistant cells have an aggressive phenotype radia?on survival prolifera?on Radia?on resistant cells have an aggressive phenotype G2/M checkpoint invasion Radia?on resistant cells have an aggressive phenotype Cross-­‐resistance to chemotherapy Radia?on resistant cells have an aggressive phenotype Implica?ons for the pa?ent: radia?on survival Increased resistance to reirradia?on? increased DNA DSB repair capacity? Cross-­‐resistance to DNA DSB cytotoxic chemotherapy? prolifera?on Faster tumor growth? invasion Increased distant metastases? microRNA may contribute towards this phenotype…. microRNA • 
What are they? •  short, non-­‐coding RNA which are altered in cancer Normal cell Cancer cell • 
What do they do? •  Decrease expression of genes • 
This dysregula?on can result in cancer development, or make cancers more aggressive and less responsive to treatments microRNA Messenger RNA (coding for a protein) Blocks protein produc?on microRNA binds to messenger RNA Why study microRNA in cancer? Biology: 1. Lead to a be]er understanding of how cancer cells can become aggressive and resistant to treatment Biomarkers: 2. Poten?al biomarkers to predict which pa?ents harbour aggressive cancer Therapy: 3. Target dysregulated microRNA in cancer to reverse treatment resistance microRNA in radia?on response •  microRNA expression pa]erns are altered by IR •  microRNA are required for the DNA damage response and they can influence cancer cell radiosensi?vity Hypothesis microRNA are involved in media?ng tumor resistance to radia?on Iden?fy microRNA •  Next-­‐genera?on sequencing of total microRNA from parental and radia?on resistant cells extract microRNA seq. microRNA Iden4fy microRNA increased in rad res cells microRNA enriched in radia?on resistant prostate cancer cells microRNA: -­‐ high expression levels -­‐ upregulated in rad res cells by at least 2x Rad res microRNA 95 Red = é rad res Green = é parental parental microRNA 95 is increased in radia?on resistant prostate cancer cells •  microRNA 95 expression is increased following radia?on treatment microRNA 95 increases radia?on resistance and prolifera?on prolifera?on radia?on survival microRNA 95 increases invasiveness control miR-­‐95 microRNA 95 decreases radia?on-­‐
induced cell senescence control miR-­‐95 microRNA 95 increases anchorage-­‐
independent growth control miR-­‐95 microRNA 95 increases prostate cancer growth and resists radia?on treatment prolifera?on necrosis control miR-­‐95 control miR-­‐95 control + IR miR-­‐95 + IR control + IR miR-­‐95 + IR microRNA 95 is increased in prostate cancer •  High microRNA 95 expression is associated with reduced biochemical relapse-­‐free survival Iden?fying targets of microRNA 95 + Overlapping genes ARPP19
MCCC2 BCAT2
NAV2 CCND1
NIPAL1 DGKD
OAZ2 DICER1
PARN DUS2L
PLEKHA1 EID1
PTPN21 EIF3B
RAI14 EMP1
RCBTB1 GCNT2
SGPP1 HAS2
TGDS HDGF
UBE4B KLHL3
ZNF614 KMO
ZNF678 SGPP1 is a target of microRNA 95 C 95 SGPP1 β-­‐ac?n •  The sphingosine pathway regulates the balance between cell death and survival Knockdown of SGPP1 promotes radioresistance PC3 DU145 FTY720 can sensi?ze microRNA 95 cells to radia?on treatment PC3 PC3 FTY720 DU145 DU145 (blocks S1P signaling) FTY720 effec?vely eliminates radia?on resistance in miR-­‐95 prostate cancer cells Model for miR-­‐95 radia?on resistance miR-­‐95 S1P SGPP1 sphingosine SK1 FTY720 PI3K -­‐ AKT cell survival prolifera?on angiogenesis ceramide cell death Clinical problem 2 •  Iden?fying pa?ents who have aggressive prostate cancer –  Allow personalized treatment decisions to be made Clinical problem 2 ‘low risk’ prostate cancer pa?ent Ac?ve surveillance •  Exam, PSA, repeat biopsy Occult high risk prostate cancer pa?ent Treat if progression (PSA, Geason) These pa?ents either have undiagnosed high risk disease upfront, or have true disease progression Iden?fy these occult high risk pa?ents upfront microRNA as predic?ve biomarkers •  microRNA are stable and detectable in urine miR-­‐95 expression is elevated Healthy volunteer Prostate cancer pa?ent Aim We will use urinary microRNA profiling of prostate cancer pa4ents to establish a non-­‐
invasive predic4ve signature to differen?ate between low and high grade prostate cancer. Protocol •  40 untreated high-­‐grade (Gleason 8+) pa?ents •  40 untreated low-­‐grade (Gleason 6) pa?ents •  Collect 50 mL of voided urine post-­‐DRE •  Isolate urine microRNA •  Perform microRNA profiling •  Generate urine microRNA signature •  Future studies: –  Valida.on Our Vision – develop a non-­‐invasive predic?ve test for high-­‐grade prostate cancer •  Urine microRNA signature will predict a pa?ent’s risk of harboring high-­‐grade prostate cancer –  In ac?ve surveillance pa?ent – detect occult high grade disease –  ‘Personalize’ treatment decisions ‘low risk’ pa?ent Urine miRNA signature ‘high grade’ profile Poor surveillance pa?ent Ini?ate treatment ‘low grade’ profile Good surveillance pa?ent Gepng research findings to our pa?ents… Summary •  Prostate cancer cells that survived radia?on treatment have an aggressive phenotype •  microRNA 95 is increased in prostate cancer and promotes cancer radia?on resistance and an aggressive phenotype •  Targe?ng the sphingosine pathway via an approved drug (FTY720) can overcome radia?on resistance mediated by microRNA 95 Summary •  Proof-­‐of-­‐principle: microRNA profile from urine is obtainable –  Early sign of ‘clustering’ of high versus low risk Ongoing research •  Therapy –  FTY720 to treat radia?on resistant prostate cancer –  An?-­‐microRNA therapy? •  Inves?gate func?on of addi?onal promising microRNA in radia?on resistance •  MicroRNA as predic?ve biomarkers in prostate cancer Xiaoyong Huang Samira Taeb Danny Vesprini Urban Emmenegger Sahar Jahngiri Elina Cook Aruz Mesci Fei-­‐Fei Liu Jeff Bruce Rob Bristow Allan E Tiffin Founda?on Paul van Slyke Dan Dumont Shan Man (Kerbel lab)