Targeted Cancer Therapy

Targeted Cancer Therapy is an umbrella term for all sorts of oncological medications that do not belong to classic chemotherapy or anti-hormonal therapy, and which are ‘otherwise’ targeted to tumour cells. Other names include:

• Targeted therapy
• Targeted therapy
• Molecular therapy
• Targeted molecular therapy
• Molecular targeted treatment

Many targeted treatments attack specific 'tumour errors'. DNA testing of cancer cells (also known as ‘molecular testing’) allows physicians to ascertain whether certain mutations (changes in the DNA) are present in the cancer cells. These mutations can cause cancer cells to continue growing and dividing. Targeted therapy can inhibit these processes.

What’s more, there are many other ways that 'targeted' therapy can help combat cancer, for example, by attacking blood vessels or proteins in the cell walls of cancer cells (receptors) or by inhibiting certain proteins within cancer cells.

Targeted therapy inhibits the signals that cause the cancer cells to grow. That is why the medications are called 'inhibitors'.

Many medications are part of the standard treatment for certain cancers, including breast cancer, colon cancer, ovarian cancer, GIST tumours, leukemia, lung cancer, Hodgkin's and non-Hodgkin's lymphoma, stomach cancer, melanoma, multiple myeloma, NET tumours, kidney cancer and oesophageal cancer.

To be considered for targeted medications, the tumour usually must exhibit certain characteristics. For targeted therapy against specific mutations, DNA testing is first necessary to form an idea about whether the targeted therapy could be effective.

A targeted therapy is often combined with other treatments, such as surgery, chemotherapy or radiation therapy, as well as other targeted treatments.

Certain targeted medications are administered intravenously or subcutaneously; others are administered in pill form.

Commonly used ‘targeted' therapies include:

ALK inhibitors: these inhibit the growth of cancer cells in certain cancers (esp. lung cancer) if there is an abnormality in the ALK gene. Examples of ALK inhibitors are alectinib (brand name Alecensa), ceritinib (Zykadia) and crizotinib (Xalkori).

Angiogenesis inhibitors: these prevent the formation of blood vessels in and around the tumour. Fewer blood vessels translate to less blood, which means less oxygen and nutrients are able to reach the tumour. Consequently, the tumour grows more slowly, stops growing or shrinks. Examples of angiogenesis inhibitors are axitinib (brand name Inlyta), bevacizumab (Avastin), pazopanib (Votrient), ramucirumab (Cyramza), sorafenib (Nexavar) and sunitinib (Sutent).

BCL2 inhibitors: in certain sorts of blood cancer (e.g. chronic lymphatic leukemia), a specific protein (BCL2) can be blocked, which helps kill cancer cells. An example of a BCL2 inhibitor is venetoclax (Venclyxto).

BRAF inhibitors: these inhibit the growth of cancer cells in certain cancers (especially melanoma) if there is an abnormality in the BRAF gene. Examples of BRAF inhibitors are vemurafenib (brand name Zelboraf) and dabrafenib (Tafinlar). BRAF inhibitors are also called ‘blockers’.

BTK inhibitors: in certain sorts of blood cancer (e.g. chronic lymphatic leukemia), a specific protein (BTK) can be blocked, which helps kill cancer cells. An example of a BTK inhibitor is ibrutinib (brand name Imbruvica).

CD30 inhibitors: in certain sorts of blood cancer (e.g. Hodgkin's lymphoma), a specific protein (CD30) can be blocked, which helps kill cancer cells. An example of a CD30 inhibitor is brentuximabvedotin (brand name Adcetris).

CD38 inhibitors: in certain sorts of blood cancer (e.g. multiple myeloma), a specific protein (CD38) can be blocked, which helps kill cancer cells. An example of a CD38 inhibitor is daratumumab (brand name Darzalex).

CDK4/6 inhibitors: inhibit the division of cancer cells in certain cancers (e.g. breast cancer). This slows the growth and spread of cancer cells. Examples of CDK4/6 inhibitors are abemaciclib (brand name Verzenios), palbociclib (Ibrance) and ribociclib (Kisqali).

EGFR inhibitors: these block a specific protein on the cell wall of cancer cells (EGFR), which plays a role in the onset of certain cancers. Examples of EGFR inhibitors are afatinib (brand name Giotrif), cetuximab (Erbitux), erlotinib (Tarceva), geefitinib (Iressa) and osimertinib (Tagrisso). EGFR inhibitors are also called ‘blockers’.

HER2 inhibitors: these block a specific protein on the cell wall of cancer cells (HER2), which plays a role in the onset of certain cancers (especially breast cancer). As a result, the tumour cells cannot divide anymore and die off. Examples of HER2 inhibitors are lapatinib (Tyverb), pertuzumab (Perjeta) and trastuzumab (brand name Hereptin). HER2 inhibitors are also called ‘blockers’.

mTOR inhibitors: inhibit the mTOR protein in certain cancers (especially kidney cancers and breast cancer), which causes the tumour cells to stop dividing. Examples of mTOR inhibitors are everolimus (brand name Afinitor) and temsirolimus (Torisel). mTOR inhibitors are also called cell-cycle inhibitors.

PARP inhibitors: these block a specific protein (PARP) that cancer cells use to repair the damage done to their DNA. Examples of PARP inhibitors are niraparib (brand name Zejula), olaparib (Lynparza), rucaparib (Rubraca) and talazoparib (Talzenna). PARP inhibitors are also called PARP inhibitors or polymerase inhibitors.

Proteasome inhibitors: these block a specific protein (proteasome) in multiple myeloma (a type of bone marrow cancer), which stops malignant cell division and allows healthy cells to start dividing again. Examples of proteasome inhibitors that are used with multiple myeloma are bortezomib (brand name Velcade), carfilzomib (Kyprolis) and ixazomib (Ninlaro). Proteasome inhibitors are also called ‘blockers’.

Tyrosinekinase inhibitors: in certain sorts of blood cancer (e.g. chronic myeloid leukemia) and in gastrointestinal stromal tumours (GIST), a specific protein (tyrosinekinase) can be blocked, which helps kill cancer cells. Examples of tyrosinekinase inhibitors are bosutinib (brand name Bosulif), dasatinib (Sprycel), imatinib (brand name Glivec), nilotinib (Tasigna) and ponatinib (brand name Iclusig). Tyrosinekinase inhibitors are also called 'blockers’.

In general, targeted medications have fewer side effects than other treatments, such as chemotherapy. They specifically target malignant cells so that healthy tissue can be spared.

With target therapy, each medication has different side effects, which differ depending on your condition and body.

The severity and frequency of side effects vary from product to product. A few examples include diarrhoea, reduced appetite, acne-prone skin and fatigue. Discuss the side effects with your attending physician, who can advise you best on how to proceed.

Source: https://www.allesoverkanker.be/doelgerichte-therapie and kanker.nl

Latest publication date: 14/01/2024