Seminario final 2012 biología molecular.laura-sebastían
1. Laura María Másmela Gil.
Sebastián Gómez Restrepo.
School of Medicine.
3th Semester.
CD24 promotes tumor cell invasion by
suppressing tissue factor
pathway inhibitor-2 (TFPI-2) in a c-Src-
dependent fashion.
Niko Bretz , Aurelia Noske, Sascha Keller , Natalie Erbe-Hofmann,
Thomas Schlange , Alexei V. Salnikov ,Gerd Moldenhauer ,
Glen Kristiansen , Peter Altevogt.
2. Introduction.
CD24.
Importantly, CD24 is
often highly
Is a glycoprotein expressed on the expressed in human
cell surface of most B solid tumors (lung,
lymphocytes and mature brain,
granulocytes; Is a cell adhesion stomach, colorectal,
molecule. prostate, breast
and ovary) and is
associated with a
poor prognosis.
3. Introduction
Increase in
number of cells
composing a
tissue.
Tumour.
A benign tumor is a type
Malignant tumors are
of tumor does not
grow disproportionately cancerous. Cancer cells can
and aggressively, does not invade and damage tissues
invade surrounding tissues. and organs near the tumor
4. Introduction
TFPI-2 The first K domain inhibits
coagulation factor VIIa
complexed to tissue factor (TF).
Human TFPI is a
physiological inhibitor of
the extrinsic pathway of The second K domain inhibits
factor Xa.
coagulation and functions in
anticoagulation and anti-
inflammation. It is a
secreted protein with three The third K domain binds to
heparin.
Kunitz (K) domains.
5. Introduction
Tissue factor (TF) is a transmembrane
glycoprotein that initiates the extrinsic pathway of
coagulation cascade and acts as a
receptor and enzyme cofactor factor VII. Also is
directly related to the aggressive cancer.
6. Introduction
C Src.
Is an endogenous protein
from the family of
tyrosine kinases, which is
present in the cytosol of
the cell.
c-Src is the gene product
of the same proto-
oncogene c-Src, that is a
precursor of a potentially
cancer causing.
8. General Objective.
• Study the mechanism of cell
FPI-2
invasion with CD24-dependent CD24 knock-
down or transient over expression in human
cancer cell lines.
15. Materiales y métodos
Es una técnica que
permite medir
Utlización de FACS
simultáneamente
Citometría de flujo Canto II FlowJo
múltiples
software.
marcadores de una
sola célula.
16. Materiales y métodos
Western blot
Detección de proteínas
Lisis celular
Mediante una electroforesis en pesadas
gel: separación de proteínas
transferencia a membrana
absorbente
Detección: anticuerpo primario-
anticuerpo secundario
17. Materiales y métodos
Separación de
Muestra de la matriz
extracelular y de
células
para
detección de la
proteína TFPI-2 se
Sembrado celular
utilizo un
anticuerpo.
Análisis
de TFPI-2
18. Materiales y métodos
Procedimiento
histopatológic
Uso de
o de cánceres
anticuerpo
de mama
especifico, Localización
primarios,
marcado con Muestra del
Inmunohisto lesiones in situ
una enzima fijada en complejo
química. de carcinoma,
que puede parafina. antígeno-
metástasis
transformar anticuerpo.
recurrentes
CD24 en
locales y
visible.
distales.
19. Resultados
La caída de CD24 afecta la invasión de líneas
celulares cancerosas.
• Se demuestra el rol de CD24 en la regulación
de la invasión de células tumorales.
• La ausencia de CD24 reduce la
invasión de células tumorales humanas.
21. Resultados
En células de carcinoma colorrectal y de
páncreas CD24 fue expresado
para controlar la expresión génica
por un mecanismo desconocido hasta ahora.
Disminución de la
expresión del CD24.
El agotamiento trasitorio
de TFPI-2 modula
la invasión de células Aumenta el TPFI-2
cancerígenas en el En todas las líneas
pulmón celulares estudiadas.
23. Resultados
• Expresión del TFPI-2 inhibe la invasión
celular.
TFPI-2 juega un papel
importante en la regulación
de la invasión de células
tumorales.
24. Resultados
• Sobre- expresión de CD24, suprime el TFPI-2;
aumentando la invasión célular.
Isoformas.
CD24-Ala CD24-Val
La expresión
de ambas formas
reduce la
cantidad del TFPI-2.
25. Resultados
Agotamiento de CD24 afecta la actividad de C Src.
CD24 se localiza en las balsas de membrana junto
con el C Src.
El eje CD24-Src juega un papel importante en la
regulación y expresión del TFPI 2.
27. Discusión
AUTHOR WHAT HE/SHE SAID AGREE DESAGREE
konduri SD and “Importantly, the up-regulation of TFPI-2 mRNA X
others was not only detected in SKOV3ip but also in
HS683 and A549 cells. Concomitantly, in all
three cell lines we noticed a significantly
reduced cell invasion that was not seen in
SNB19 cells having no detectable levels of TFPI-
2.”
Sierko E, “Our findings establish a link between CD24 X
Wojtukiewicz and TFPI-2, a proteinase inhibitor known for its
MZ, Kisiel W important role in the inhibition of tumor cell
invasiveness, neoplastic growth, and
metastases formation”
28. DISCUSIÓN
AUTHOR WHAT HE/SHE SAID AGREE DESAGREE
Taniuchi K, “In the presence of CD24 the x
Nishimori I, cleavage of BART
Hollingsworth mRNA by G3BP was blocked
MA whereas both BART or
CD24 siRNA depletion resulted in
enhanced cell motility
and invasion”
Sierko E, “The TFPI-2 gene is considered a x
Wojtukiewicz tumor suppressor
MZ, Kisiel W gene as its down-regulation or loss
is associated with
increasing malignancy”
31. conclusiones
• 1. In summary the results demonstrate for the
first time that CD24 can regulate the
expression of TFPI-2.
• 2. it was showed that cellular invasion was
significantly reduced after CD24 knock down
or after TRPI-2 overexpression
32. conclusiones
• 3. these findings suggest that the depletion of
CD24 in malignant tumors might offer a new
possibility to interfere with tumor progression.
• 4. in clinical practice is important to
know about the expression of CD24 and TFPI-
2 in tumor invasion or no invasion of
many body cells for potential cancer
treatments.