Cancer metastasis

Definition

Cancer metastasis is the process by which cancer cells spread from their original site to other parts of the body, forming secondary tumors. This occurs when cancer cells invade nearby tissues, enter the bloodstream or lymphatic system, and establish new tumors in distant organs. Understanding this process is crucial, as it significantly impacts the progression of cancer and affects treatment strategies.

5 Must Know Facts For Your Next Test

1. Metastatic cancer is often more challenging to treat than localized cancer due to its ability to spread to multiple sites.
2. The steps involved in metastasis include local invasion, intravasation into blood vessels, survival in circulation, extravasation into new tissues, and colonization to form new tumors.
3. Certain types of cancer, such as breast and prostate cancer, have well-known patterns of metastasis to specific organs like bones or lungs.
4. Cell adhesion molecules play a crucial role in metastasis by allowing cancer cells to detach from the primary tumor and attach to new sites in the body.
5. Therapies targeting metastasis are an active area of research, focusing on disrupting the pathways that facilitate the spread of cancer cells.

Review Questions

• How do microtubules contribute to the process of cancer metastasis?
  • Microtubules are essential components of the cytoskeleton that help maintain cell shape and facilitate intracellular transport. In cancer metastasis, microtubules aid in cell movement and enable cancer cells to migrate from the primary tumor site through local tissues. By providing structural support for cellular processes like invadopodia formation and motility, microtubules play a vital role in the ability of metastatic cells to invade surrounding environments and enter the bloodstream.
• Discuss how cell-cell junctions influence the metastatic behavior of cancer cells.
  • Cell-cell junctions, such as adherens junctions and tight junctions, are critical for maintaining tissue integrity and regulating cell behavior. In metastatic cancer cells, changes in these junctions allow them to become more invasive by breaking down adhesive interactions with neighboring cells. When these junctions are weakened or altered, cancer cells can detach from their primary location, facilitating their migration into surrounding tissues and ultimately contributing to the formation of secondary tumors.
• Evaluate the role of the extracellular matrix in supporting or inhibiting cancer metastasis.
  • The extracellular matrix (ECM) plays a dual role in cancer metastasis, either promoting or inhibiting the spread of cancer cells. On one hand, a remodeled ECM can provide a conducive environment for metastatic cells by secreting growth factors and facilitating cell attachment. On the other hand, an intact ECM can act as a barrier that limits invasion and spread. Understanding how the ECM interacts with tumor cells during metastasis can lead to novel therapeutic approaches aimed at altering these interactions to inhibit cancer progression.

Related terms

angiogenesis: The formation of new blood vessels from pre-existing ones, which is essential for providing nutrients to growing tumors and facilitating metastasis.

extravasation: The process by which cancer cells exit the bloodstream and invade surrounding tissues to establish secondary tumors after entering circulation.

tumor microenvironment: The surrounding environment of a tumor, including nearby cells, signaling molecules, and extracellular matrix, which influences tumor growth and metastasis.