Find information on thousands of medical conditions and prescription drugs.

Herceptin

Trastuzumab (Herceptin®) is an anti-cancer therapy that acts on the HER2/neu (erbB2) receptor. "Receptors" are usually protein molecules on the surface of a cell which allow the cell to respond to hormones and other signals from other cells. Herceptin's principal use is in breast cancer in patients whose tumors overexpress (produce more than the usual amount of) this receptor. Trastuzumab is administered either once a week or once every three weeks intravenously for 30 to 90 minutes. more...

Home
Diseases
Medicines
A
B
C
D
E
F
G
H
Habitrol
Halcion
Haldol
Haloperidol
Halothane
Heparin sodium
Hepsera
Herceptin
Heroin
Hetacillin
Hexachlorophene
Hexal Diclac
Hexal Ranitic
Hexetidine
Hibiclens
Histidine
Hivid
HMS
Hyalgan
Hyaluronidase
Hycodan
Hycomine
Hydralazine
Hydrochlorothiazide
Hydrocodone
Hydrocortisone
Hydromorphone
Hydromox
Hydroxycarbamide
Hydroxychloroquine
Hydroxystilbamidine
Hydroxyzine
Hyoscine
Hypaque
Hytrin
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z

Mechanism of action

Amplification of ErbB2 occurs in 30% of early-stage breast cancers (Bange et al 2001). It encodes the transmembrane tyrosine kinase p185-erbB2 glycoprotein. Although the signaling pathways induced by the erbB2 receptor are incompletely characterized, it is thought that activation of the PI3K/Akt pathway is important. This pathway is normally associated with mitogenic signaling involving the MAPK pathway. In cancer growth producing signals from erbB2 are constitutively transmitted, promoting invasion, survival and angiogenesis of cells (Ménard et al 2003). Furthermore overexpression can also confer therapeutic resistance to cancer therapies. Kute et al. (2004) suggest that the prime mechanism that causes increase in proliferation speed is due to induction of p27Kip1, an inhibitor of cdk2 and of cell proliferation, to remain in the cytoplasm instead of translocation in to the nucleus. This is caused by phosphorylation by Akt.

Herceptin is a monoclonal antibody which binds to its extracellular segment of the erbB2 receptor. Cells treated with Herceptin undergo arrest during the G1 phase of the cell cycle and experience a reduction in proliferation. It has been suggested that Herceptin induces some of its effect by downregulation of erbB2 leading to disruption of receptor dimerization and signaling through the downstream PI3K cascade. P27Kip1 is then not phosphorylated and is able to enter the nucleus and inhibit cdk2 activity, causing cell cycle arrest (Kute et al 2004). Also, Herceptin suppresses angiogenesis by induction of antiangiogenic factors and repression of proangiogenic factors. It is thought that a contribution to the unregulated growth observed in cancer could be due to proteolytic cleavage of erbB2 that results in the release of the extracellular domain. Herceptin has been shown to inhibit erbB2 ectodomain cleavage in breast cancer cells (Albenall et al 2003). There may be other undiscovered mechanisms by which Herceptin induces regression in cancer.

Impact

Herceptin has had a "major impact in the treatment of HER2-positive metastatic breast cancer" (Tan and Swain 2002). In combination with chemotherapy Herceptin has been shown to increase both survival and response rate in comparison to Herceptin alone (Nahta and Esteva 2003). It is possible to determine the 'erbB2 status' of a tumour, which can be used to predict efficacy of treatment with Herceptin. If it is determined that a tumour is overexpressing the erbB2 oncogene then a patient is eligible for treatment with Herceptin (Yu and Hung 2000). It is surprising that although erbB2 has great affinity for the receptor and the fact that such a high dose can be administered (due to its low toxicity) 70% of patients do not respond to treatment. In fact resistance is developed rapidly on treatment of virtually all patients. It is suggested that a mechanism of resistance is the lack p27Kip1 translocation to the nucleus in some strains, enabling cdk2 to induce cell proliferation (Kute et al., 2004).

Read more at Wikipedia.org


[List your site here Free!]



Portrait of a cancer drug at work - Biomedicine - breast cancer drug Herceptin binds to and inhibits the protein HER2 on cancer-cell surfaces - Brief Article
As researchers seek better drugs for breast cancer, they have a revealing new picture that could guide their way. It shows where the breast cancer drug ...
Trastuzumab for Metastatic Breast Cancer - Herceptin
Trastuzumab is not the first monoclonal antibody to be used as an anti-tumor agent, but it may be the most publicized. In about one third of breast cancers, the human epidermal growth factor recept
Speaking of people
James D. White SAFEWAY'S SENIOR VICE PRESIDENT, CORPORATE BRANDS James D. White is senior vice president of corporate brands for Safeway, one of the ...
Not another magic bullet - Herceptin for breast cancer
Medical breakthroughs are rare, but the new breast cancer drug trastuzumab (Herceptin) was launched yesterday with all the buzz words we associate with ...
Cancer drug may cause heart failure - Herceptin - News
A team of researchers is calling for long term studies investigating the risk of heart failure among women taking the breast cancer drug trastuzumab ...
Herceptin Linked to Serious Side Effects, Deaths - Brief Article - Statistical Data Included
Genentech has issued a warning about serious side effects that have been reported in women who have been treated with Herceptin, the monoclonal antibody ...
First case over Herceptin is back in court
A MOTHER of two will today mount a legal challenge to her local NHS trust's refusal to give her the breast cancer drug Herceptin. Ann Marie Rogers, ...
Herceptin fight woman is clear of breast cancer
A MOTHER who won a battle with the National Health Service to make a lifesaving drug available to breast cancer sufferers has beaten the disease. Barbara Clark, 49, of Bridgwater, was given a

Home Contact Resources Exchange Links ebay