Samenvatting
Summary Pecorino Molecular Biology of Cancer Ch. 9
This is an extensive, English summary of Pecorino's 'Molecular Biology of Cancer' book, Ch. 9 – about metastasis.
[Meer zien]Voorbeeld 1 van de 4 pagina's
Voorbeeld 1 van de 4 pagina's
In winkelwagengesponsord bericht van onze partner
Gekoppeld boek
Titel boek:
Auteur(s):
- Uitgave:
- ISBN:
- Druk:
1 beoordeling
Door: dorindeminderman • 3 jaar geleden
Voorbeeld van de inhoud
Oncology 9HC 6
9.1
Organs have well-defined boundaries defined by basement membranes which are acellular
structures made up of extracellular matrix proteins, which keep cells in place. Tumor cells
however compromise this system and are able to metastasize; tumors from a primary site
are able to break free and spread to a distant site. This characteristic feature is only one of
malignant tumors. Metastasis is what makes a cancer lethal, as it interferes with organ
function by physically obstructing or by competing with normal cells for nutrient and
oxygen. It appears though, specific tumors primarily metastasize to certain organs; they
show a preference for an organ, organotropism. This is partially explained by the
directionality of the blood flow, but not always. Cancer cells are like seed and soil; the
metastasizing cells are the seeds, but these require a proper soil to grow. The soil would be
a pre-established niche for the seeds of metastasized tumors to grow. The ability to
metastasize anyway depends on the interactions with cancer cell surface molecules and the
microenvironment (including the ECM). This idea gave rise to the phenomenon of the pre-
metastatic niche. This is a site of future metastasis that is altered to optimally host
metastasized tumor cells in the future. Such an environment is prepared by factors secreted
by the tumor itself, which thus prepare the environment for its arrival.
The metastatic tumor cells from a primary tumor are not clonal, but rather composed of
subpopulations from a genetically identical cells (subclones) differing in mutations due to
evolution. Spreading nevertheless can be monoclonal, seeding by one cell, or polyclonal,
with seeding by multiple subclones. Moreover, the spreading can be linear, one primary
tumor and one metastasis, or branched, with one primary tumor and multiple metastases.
9.2
Metastasis, like carcinogenesis, is a multi-step process on itself. The major steps include
invasion, intravasation, transport, extravasation, and lastly, metastatic colonization.
Additionally, a tumor must not be seen as a clump of proliferating cells, but also the tumor
microenvironment and the tumor-associated stroma is equally important. The metastatic
ability is even determined by the microenvironment.
9.3
The first step of metastasis is invasion. A primary tumor must be able to break free from the
constraints of the local environment and acquire migratory characteristics. This acquisition
or change of the tumor is termed, epithelial-mesenchymal transition (EMT). It is a
conversion of closely connected epithelial cells to highly mobile mesenchymal cells. The
process of EMT is common in embryogenesis, as it is needed for gastrulation and pattern
formation; so, this is another process reactivated in cancer cells. Important characteristics of
EMT include loss of cell polarity, deconstruction of cellular junctions, downregulation of
epithelial markers and the upregulation of mesenchymal markers.
EMT is induced by the tumor-associated stroma which releases factors that stimulate the
transition. Ligand-bound tyrosine kinase receptors on tumor cells activate certain signaling
Voordelen van het kopen van samenvattingen bij Stuvia op een rij:
Verzekerd van kwaliteit door reviews
Stuvia-klanten hebben meer dan 700.000 samenvattingen beoordeeld. Zo weet je zeker dat je de beste documenten koopt!
Snel en makkelijk kopen
Je betaalt supersnel en eenmalig met iDeal, creditcard of Stuvia-tegoed voor de samenvatting. Zonder lidmaatschap.
Focus op de essentie
Samenvattingen worden geschreven voor en door anderen. Daarom zijn de samenvattingen altijd betrouwbaar en actueel. Zo kom je snel tot de kern!
Veelgestelde vragen
Wat krijg ik als ik dit document koop?
Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.
Tevredenheidsgarantie: hoe werkt dat?
Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.
Van wie koop ik deze samenvatting?
Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper noahdekker84. Stuvia faciliteert de betaling aan de verkoper.
Zit ik meteen vast aan een abonnement?
Nee, je koopt alleen deze samenvatting voor €3,49. Je zit daarna nergens aan vast.
Is Stuvia te vertrouwen?
4,6 sterren op Google & Trustpilot (+1000 reviews)
Afgelopen 30 dagen zijn er 80461 samenvattingen verkocht
Opgericht in 2010, al 14 jaar dé plek om samenvattingen te kopen