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Kinase Typing and IHC - Screening for Better Chemotherapy?

Posted: Mon Feb 18, 2008 10:36 pm
by Fictional
As suggested by Olga, I opened up a new topic here to share our experiences with Kinase typing and immunohistochemistry.

We were interested in pursuing this because there are no established successful protocols for ASPS, and it is possible that tissue typing tumors can help patients and their doctors arrive at a more successful chemotherapy combination, than trial and error alone. There is a lot of interest in this approach, but until it can be proven to make a difference on a large scale, it will not become "standard practice."

Most studies of this sort can be performed on paraffin blocks. In the U.S., hospitals and labs are required by law to hold onto the paraffin blocks for at least 10 years, so potentially even if a tumor has been removed some years ago, a patient can request that a few sections be sent for testing by an outside lab.

The caveats are that primary tumors and metastatic tumors may have very different profiles. We have only just had our daughter's primary tumor removed (and so those are results we show below), but if we can, we will send some of the metastatic nodules for additional testing because we plan to have these surgically resected.

I was impressed by how little the standard stains at UCLA could tell us about possible useful chemotherapeutic agents: NEGATIVE ER, PR, HER-2, CD20, c-kit, EGFR We requested estrogen and progesterone because of one paper in a gynecological ASPS that reported estrogen and progesterone receptors.

Because 'K''s ASPS was gynecological, we were able to have a charitable organization (for female cancers) pay for typing of her cancer at Clarient (www.clarientinc.com). They had their results in 3 days and also provide digital copies of the slides.

Clarient: c-myc FISH NOT amplified
topo-isomerase II-alpha NOT amplified
thymidylate synthase (TS) Negative
COX2 POSITIVE (100% cells, 1-2 intensity)
PTEN NO loss of expression
Tau POSITIVE (2+)
VEGF POSITIVE (90% cells, 2-3+ intensity)
ERCC1 HIGH (100% cells, 3 intensity)
GST pi Low (0% cells, 0 intensity)
PDFR Alpa Negative
PDFR Beta POSITIVE (100% cells, 2 intensity)

If I understand the results well, certain chemotx seemed less preferred (e.g. cisplatin, taxol, herceptin, etc.), while anti-angiogenic agents (sutent, nexavar, celebrex, vinblastine) were still strong candidate drugs.

UCLA also sent the tumor tissue for c-met staining at Sloan Kettering (this can be done as a routine "second opinion"), and it came back positive - suggesting that the new oral c-met inhibitors under clinical trial would also be good candidates.

In our situation, we've been told that her nodules look completely resectable, so we are looking at chemo as a neoadjuvant, to be used prior to resection. The rationale for neoadjuvant use is that if patient can take a drug for a few cycles before the tumors are resected, one can find out from the pathologist whether the drug looks effective (the pathologist should see cell death) before to committing to many months (or more) of post-op treatment.

The dilemma with many of the newest "smart drugs" is that even if the are effective at stabilizing disease, they may only put the cells asleep so that although they do not grow and divide, they do not die either - raising the risk that they can waken again at some point and regrow. Because ASPS can send out tumors over such a long period, the ideal drug is one that can induce tumor cell death.

In our situation Sutent was somewhat disappointing because we found only 5% treatment effect (cell death) in the primary. Still it helped a little in that it inhibited primary tumor growth for 6 months - and that time allowed us to find a second opinion and surgeon who could resect the tumor cleanly without undue morbidity...

We have a greater respect for pathology as the MRI of her primary suggested more extensive central necrosis. That means MRI may suggest significant death of the tumor, but it might not really be dead. We also tried PET, but we were told the SUV's were so low in her case (2.3) at baseline, it would not be reliable to see a decrease.

Hope this might help someone. Please feel free to email off list with any questions.

Posted: Tue Feb 19, 2008 2:24 am
by Olga
hi, I wanted to post a few comments here:
1. We had a girl who's tumor was extensively tested and the result was used as a rationale for the targeted therapy, it didn't produce any miracle results. The lab was different tough.
2. Her primary tumor and her lung mets were tested for estrogen and while primary was negative lung mets were 60 % positive. There might be organ specific difference.
3. 5 % necrosis in the primary tumor might have been spontaneous, usually it is even bigger with no treatment.
4. c-met is an interesting target, I think I saw some article on ASPS and c-met.
I am glad to hear that her lung mets are resectable!

Posted: Sun May 04, 2008 7:01 am
by Fictional
Quick update here about profiling we did on 'K''s lung nodules.

Largest and a representative small nodule were also sent for IHC at Clarient. The large nodule (0.9 mm) was also sent for met staining.

We found a variations in Ki67 that seemed to reflect rate of growth.
Primary was 26%, large nodule was 40%, and small nodule was 5%.

Primary was positive for Cox2, MET, Tau, 90% VEGF, 100% PDGFbeta, low GSTpi.

Largest lung: negative for Cox2, Met, Tau;60% VEGF, 70% PDGF beta, high GSTpi.

Representative small lung: negative for Cox2 and Tau, Met not tested; VEGF and PDGF beta negative, low GSTpi.

Learning about the variation was a bit discouraging, but it suggested that medical + surgery therapy is a reasonable course of action (e.g. kill off some clones that you can with medical intervention, surgical resect if they don't respond).

Re: Kinase Typing and IHC - Screening for Better Chemotherapy?

Posted: Tue Dec 16, 2008 8:41 am
by Fictional
Hi there and happy holidays,

I just wanted to update our latest results with molecular profiling. We had the nodules from Germany (thoracotomy #2) sent to UCLA for further studies and confirmation. I posted a screenshot from her pathology under updates ARQ I think. It is nice to see necrotic tumors, but of course we wish there were more of them. That was early in the course of ARQ/Celebrex though.

The nodules were sent to Clarient and TMD (Targeted Molecular Diagnostics) - path obtained after 13 wks ARQ197/5wks high dose Celebrex.

1 untreated: 25% Ki67 (marker for proliferative rate), wildtype for Kras

2 with treatment effects (40, 80% necrotic): 37% Ki67, 52% Ki67 respectively

all three are negative for COX2 and negative for MET.

Results like these reinforced how difficult it is to interpret molecular profile results as our daughter continues on ARQ197 (now 6 months) and high dose Celebrex (5 months). Her course however if anything has quieted down (thank the Lord). No definitely new nodules for the past 6 months. Before that had been a trickle of new metastases with every scan. Her primary was removed 11 months ago.

The treatment effect - central necrosis in the most rapidly dividing nodules apparently is the most common finding in a "chemotherapeutic effect" for conventional agents. Because the disease seems to have stabilized as COX2 and met became negative ('K''s primary is highly met positive and 100% COX2 positive), we are interpreting the results as a good thing. In other cancers, the presence of met and COX2 correlates with worse prognosis, shorter survival, and more aggressive metastases. We know of 4 other ASPS patients who have had met-positive metastases and at least one ASPS with partially COX2 positive metastasis. So it met and COX2 positive occurs in metastases in at least some ASPS patients. Of course it is also possible we are continuing on a met inhibitor and celebrex for no reason...but as there have been no side effects, we think we are content to continue as we are.

The wildtype Kras was good to see. If the mutation were present, it would suggest that inhibiting met wouldn't have any benefit (Kras is downstream to met).

I did speak to our biotech friend about these latest results. She said in ovarian cancer it is not uncommon to see VEGF levels drop in the presence of Avastin. So it may be the absence of met and cox2 in the metastases is a result of ARQ and Celebrex. We also found a higher level of VEGF in our daughter's primary tumor vs. the lung mets - and this may have been because she was taking Sutent x 6 months. We did not check VEGF/PDGF this latest time - because last testing showed at least one live nodule negative for VEGF and PDGF. Because the charitable organization picks up anything our insurance doesn't pay we didn't want to order any more tests than necessary.

In our minds, all this still supports surgery as the ultimate option for removing persistent or chemo-resistant metastases.

Re: Kinase Typing and IHC - Screening for Better Chemotherapy?

Posted: Tue Dec 16, 2008 8:44 am
by Fictional
Oops. P.S. We also checked IGFR because of possible interest in R1507 in ASPS. The metastases were negative for IGFR so we are unlikely to go down that route.