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View Full Version : another reason not to get stressed out--study suggests herceptin may not work as well


Lani
05-20-2008, 07:02 AM
in those stressed out. Herceptin's effect is felt to be primarily through an immune reaction which in part depends on NK cells

J Surg Res. 2007 May 1;139(1):36-44. Epub 2007 Feb 9. Links

Impaired natural killer cell lysis in breast cancer patients with high levels of psychological stress is associated with altered expression of killer immunoglobin-like receptors.

Varker KA, Terrell CE, Welt M, Suleiman S, Thornton L, Andersen BL, Carson WE 3rd.
Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA.
BACKGROUND: We previously reported that cancer-related psychological stress is associated with reduced natural killer (NK) cell lysis. We hypothesized that reduced NK cell cytotoxicity in patients with increased levels of stress would correlate with alterations in the expression of inhibitory NK cell receptors (killer immunoglobulin-like receptors, or KIRs). The specific aim of this study was to examine KIR expression in patients with high or low levels of psychologic stress and correlate alterations in KIR expression with NK cell function. MATERIALS AND METHODS: Two hundred twenty-seven patients underwent baseline evaluation of cancer-related psychological stress and were randomized to psychosocial intervention versus observation. From this population, two groups were defined based on pretreatment measurements of NK lytic activity, stress levels, and the availability of cryopreserved peripheral blood mononuclear cells (PBMC). Group I (n=9) had low stress by the Impact of Events Scale (IES), and high NK cell lysis at the 50:1 effector: target ratio (NK(50)=52-89%). Group II (n=8) had high stress and low NK(50) (27-52%). Lymphokine activated killer (LAK) activity, antibody dependent cellular cytotoxicity (ADCC), and expression of cytokine receptors, adhesion molecules, and killer immunoglobulin-like receptors (KIRs) were assessed in PBMC. RESULTS: Incubation of PBMC with NK-stimulatory cytokines (IL-2, IL-12, or IL-15) led to significant increases in cytotoxic activity regardless of IES/NK(50) scores. There were no significant group differences in NK cell surface expression of the IL-2 receptor components CD25 and CD122, antibody-dependent lysis of HER2/neu-positive SKBr3 cells treated with an anti-HER2/neu monoclonal antibody, expression of adhesion molecules (CD2, CD11a, CD18) and markers of activation (CD69), or expression of the KIRs CD158a, NKG2a, NKB1, and CD161. However, levels of CD158b were significantly higher in Group I after incubation in media alone or with IL-2, and CD94 expression was significantly lower in Group I after incubation with IL-2. CONCLUSIONS: In this study of a small subset of breast cancer patients chosen from a previous clinical trial of psychosocial intervention for breast cancer, impaired NK lysis in breast cancer patients with high levels of psychological stress was associated with alterations in surface expression of killer immunoglobulin-like receptors. However, immune effectors retained the ability to lyse antibody-coated targets and to initiate lymphokine-activated killer activity, irrespective of stress levels or baseline NK(50).

Unregistered
05-20-2008, 08:22 AM
Hi Lani,

I don't understand this study, nor do I see anything about Herceptin. If the bottom line is the last sentence, it seems to be saying stress makes no difference in the end although it may affect measurement of some factor midstream in the process (whatever the process is - I'm a little unclear about those targets in the cell culture - are they talking cancer cells?)? Do you have a minute to interpret this for us?

This esoteric study in a lab seems a far distance from having implications to living beings.

Debbie Laxague, not unregistered - not sure what happened with that

Hopeful
05-20-2008, 08:37 AM
Debbie,

If you look in the RESULTS section of the abstract, you will see:

"There were no significant group differences in NK cell surface expression of the IL-2 receptor components CD25 and CD122, antibody-dependent lysis of HER2/neu-positive SKBr3 cells treated with an anti-HER2/neu monoclonal antibody, expression of adhesion molecules (CD2, CD11a, CD18) and markers of activation (CD69), or expression of the KIRs CD158a, NKG2a, NKB1, and CD161."

The phrase, "anti-Her2/neu monoclonal antibody," I believe, refers to Herceptin.

As to the conclusion, I read this the same way that you did, i.e., stress was not a factor.

Hopeful

Lani
05-20-2008, 09:28 AM
the entire article which is available free online

Figure 3 and other aspects of the text explain my concern

Paris
05-21-2008, 06:16 AM
Hi Lani, Could you either post or link to figure 3? I was able to find article on pubmed but not figure 3 (although it's the first time I've pulled something up on that site). Thanks!