Exosomes are smallest extracellular vesicles of size 30 to 100 nm originated from late endosomes. These are released by broad array of cells including B‐ cells, cells, dendritic cells (DCs), T‐cells,  epithelial cells,  platelets and many more.

1. KESHAV RAJ BHUSAL
U N I V E R S I T Y O F O S L O
F A C U L T Y O F M A T H E M A T I C S A N D N A T U R A L S C I E N C E
D E P A R T M E N T O F B I O S C I E N C E S
Exosome and Cancer

2. Background and introduction
 Extracellular membrane vesicles(EMV) are
phospholipid bilayered vesicles from the eukaryotic
cell.
 Distinct biogenesis pathways lead to different types
of EMV
 Exosomes
 Shedding microvesicles
 Apoptotic blebs(Abs)
 communication medium between the cells

3. Background and introduction
Cell Mol Life Sci 68 (2011) 2667–2688.

4. Background and introduction
 Exosomes are smallest extracellular vesicles.
 Size=30–100 nm
 originates from late endosomes.
 Released in the extracellular medium by a broad
array of cells.
 First identified in sheep red blood cell ( 1983) -
Believed to be a mechanism for the exchange of
proteins between cells.

5. Background and introduction
 Believed to be a mechanism for the exchange of
proteins between cells.
 became interest for immunologists , when they were
proposed to play a role in antigen presentation(1996)
 finding by Hadi Valadi
 exosomes carry mRNA and miRNA,
 capacity to vehicle genetic messages.

6. Biogenesis and release of exosome
Raposo G , and Stoorvogel W J Cell Biol 2013;200:373-383

7. Biogenesis and release of exosome
 Released by
 B‐cells,
 dendritic cells (DCs),
 T‐cells,
 epithelial cells,
 platelets
 present in physiological fluids
 serum,
 urine,
 breast milk,
 cerebrospinal fluid,
 saliva

8. Composition of exosome
Virol. 2011;85:12844-12854

9. Antitumorigenic Role of
Tumor-Derived
Exosomes

10.  Due to their protein and nucleic acids contents, which
closely reflects the nature and state of their parental cells,
exosomes are considered veritable concentrations of
information.
 All of the molecules found in exosomes are potentially
useful for diagnostic purposes
 screening testing,
 confirmatory diagnostics,
 patient profiling,
 monitoring of treatments.

11. Immunogenic properties
 exosomes derived from tumor cells have been shown
to have anti-tumorigenic properties
 inducing tumor cell apoptosis (Ristorcelli et al., 2008)
 enhancing anti-tumor immunity (Zhang et al., 2010)
 tumor-derived exosomes have been used as a source
of tumor antigens to pulse DCs(Taieb et al., 2006)
Exosome transfer tumer Ag to DC induce CD8+ Tcell
dependent antitumer effect

12. Induction of tumor cell apoptosis
 Apoptotic function of tumor-derived exosomes on
tumor cells was also reported( Ristorcelli et al, 2008)
human pancreatic tumer cell exosome increase
Bax/Decrease Bcl2 expression tumer cell towards
mitochondrial apoptotic pathway

13. Conclusion
 Increasing evidence suggests that tumor-derived
exosomes can confer anti-tumorigenic effects.
 Some evidence also suggest exosomes also have
protumerogenic effect.
 These controversial effects can be the results of
complex interactions between exosomes, responding
cells, and environmental factors.
 A better understanding of the roles of tumor-derived
exosomes in cancer pathogenesis is needed to further
improve anti-cancer therapeutics as well as
exosome-based cancer diagnostics.

14. Suggested video on you tube
(Documentary by life technologies)
 Episode 1- What is exosome
(https://www.youtube.com/watch?v=sE2krsErbwI)
 Episode2- The history & promise of exosome
(https://www.youtube.com/watch?v=Ry9kL-R-7E8)
 Episode3- Exosomes in cancer research
(https://www.youtube.com/watch?v=SZZ_-fnkEVc)
 Episode4- Curiosity and a passion for science
(https://www.youtube.com/watch?v=Lsz8sMBxyyM)
 Episode5- collaboration,the key to scientific research
(https://www.youtube.com/watch?v=-wz90lVQE9w)
 Episode6- The next small thing
(https://www.youtube.com/watch?v=EB_uI9STq-I)

15. THANK YOU