The opposite of what we knew…

Do you remember all the hoopla caused by a June 2009 study on green tea and bortezomib? If not, please click here: That study came as very bad news for devoted green-tea-drinking patients on Velcade, even though, as Dr. Durie pointed out during a patient seminar that I attended last fall, those patients can still have their cuppa…just not on their Velcade days…

Now for today’s topic. Not too long ago, a blog reader (thanks!) reminded me of a November 2009 study that I had read in December but hadn’t posted about… Sherlock, grazie!, sent me the full study, whose main result is spelled out in the abstract ( EGCG is synergistic with bortezomib (=Velcade) against the KM3 multiple myeloma cell line. SYNERGISTIC??? That means that EGCG and Velcade are more efficient myeloma cell assassins when used together

Wait a sec…in June we were told that EGCG antagonizes bortezomib (see:, full text also available for free)…this group of researchers found that not only was EGCG not toxic or (at higher concentrations) only mildly toxic to myeloma cells, but also it prevented bortezomib from doing its job. In other words, based on the June study, EGCG actually protected the myeloma cells…from bortezomib.  

When I first read and posted about the June study, I don’t remember being bothered by the occasionally arrogant language used by the authors…especially in this excerpt about EGCG: this “miracle herb” extract is also consumed by many cancer patients who follow popular trends and self-medicate with complementary and alternative medicine (CAM) in hopes to support their conventional therapy or to lessen the burden of side effects—sometimes without the knowledge of their health care provider. “Popular trrrends”??? I say, I am feeling quite offended right now…how did I miss that condescending tone when I first read the study last year? Well, I suppose I was more focused on the importance of the issue at hand, i.e., warning Velcade-users against taking EGCG or even drinking green tea…

I also (!) didn’t question the finding that EGCG, when used alone, wasn’t able to kill even one miserable little myeloma cell, even at concentrations that are much greater than the typical concentrations achieved in humans. This is contrary, e.g., to the results of an authoritative 2006 study (see:… Makes me wonder…

One more thing. I would like to point out that, incredibly, the online media paid no attention whatsoever to the November pro-EGCG study, whereas the complete opposite is true of the June anti-EGCG study…in fact, if you do a quick online search, you will still find warnings, even recent ones, about drinking green tea with bortezomib…even if you type the words “EGCG” “bortezomib” and “synergy.”

What you will not find (at least I did not) is the slightest mention of the November 2009 study, the one with the synergy results. That story just wasn’t picked up, for…some reason (I can only guess…). Well, today I decided to fill the gap…not because I think that the November study is a better one, that is not for me to judge!, but because I don’t think it fair that this study be so blatantly ignored…

Okay, for reasons of simplicity, from now Study A will be the June anti-EGCG with bortezomib study, and Study B will be the November pro-EGCG with bortezomib study.

Just a quick glance at the two studies showed that there were differences in caspase activation…In Study A, EGCG blocked the activation of caspase-7, which essentially stopped bortezomib from exterminating the myeloma cells. In Study B, instead, EGCG activated different caspases, specifically caspase-3, -8 and -9, leading to the death of the myeloma cells. Some day I should really look into this caspase business…until then I will not be able to figure out how, why or if this might be significant (I’d be glad for some help, here!)…

For lack of time, sorry, I am going to jump to the Discussion part of Study B. As I had hoped, this is where the authors compare their own results to the ones of Study A (identified as “they” in the following excerpts):

-They use a relative [sic] lower concentrations of EGCG (10 mM) and bortezomib (10 nM), whereas we used a relative [sic] high concentration of EGCG (25, 50, and 100 mM) and bortezomib (20 nM). So let’s see…Study A used a lower dose of EGCG and bortezomib, Study B a higher one. Okay, that is certainly a difference.

-We focused on the mechanism of EGCG inhibiting myeloma cell growth and inducing cell apoptosis potentiated by bortezomib, whereas they focused on the effect of EGCG on bortezomib in myeloma cells. So, we found that EGCG inhibits myeloma cell growth and induces cell apoptosis potentiated by bortezomib. This part wasn’t clearly worded, in my opinion (but it is true that I just got over a cold…is my mind still fogged by a bit of congestion?). In fact, I don’t see any difference at all…Mental note: I need to find the time to compare how the experiments were carried out in both studies.

-This may be because of different drug concentrations or different cell lines. Study A and B (and even the above-mentioned 2006 study, by the way) tested EGCG and bortezomib on different myeloma cell lines. And different doses were used in both studies. Is that enough to explain their differing results? Possibly.

I found myself wondering about the different myeloma cell lines used in different studies. Interesting topic. I had no idea that there were so many myeloma cell lines. I began doing some research but had to give up. Too complicated and time-consuming…

Well, I admit, I am still baffled. I suppose that I would still be cautious about taking green tea or EGCG with Velcade. I would follow Dr. Durie’s suggestion. Best to be cautious. Still, Study B gives us some (green) tea for thought and shows how much we still have to learn…

P.S. Here is a list of things that Velcade patients should avoid taking:

Curcumin beats chemoresistance and helps thalidomide and bortezomib fight myeloma

A new study, carried out by a group of MD Anderson researchers and published this month in “Molecular Cancer Therapeutics” (see abstract: confirms what we already knew about curcumin’s synergy with bortezomib.*


The researchers performed experiments on myeloma cells and also on nude mice. Now, since I frequently read about “nude mice,” some time ago I gathered the courage to do a bit of research… almost wish I hadn’t!…at any rate, these mice are simply hairless (hence their nickname “nude”), not in need of a new set of clothes. Most importantly, though, due to a genetic mutation, they are born without a thymus and thus have an inhibited immune system, which means that they are not able to reject tissue or tumour grafts (they also have little or no defence against viruses and all sorts of nasty stuff, poor dears). Therein lies their usefulness.


Now, let me state that, after reading about nude mice, not to speak of other lab animals!, I finally stopped regretting that I didn’t choose science as my major in college and grad school. Ah yes, I’d have been the crazy student taking all the nude mice home, wrapping them in warm shawls and keeping them as pets…hmmm, something tells me that my brilliant scientific career wouldn’t have lasted very long…


Okay, now that that is all cleared up, and I have admitted publicly to how silly I am, let’s proceed. An important result of this new study is that curcumin inhibited the proliferation of human multiple myeloma cells regardless of their sensitivity to dexamethasone, doxorubicin, or melphalan. The wonderful orange powder also helped bortezomib and thalidomide kill myeloma cells by reducing NF-kappaB’s incessant hyperactivity (=a bad BAD thing!), which also affected the gene products under its control (cyclin D1, etc.).


Going on to the full study, now (grazieeee, Sherlock!). After a paragraph dealing with the usual dire myeloma statistics, blablabla, we find out that the researchers used C3 Complex, the curcumin that I (and many others) take. Good to know.


And then we get to the actual experiment, which I will try to summarize. The nude mice were divided into four groups: 1. the control group, which was treated just with corn oil and saline; 2. the curcumin alone group (1 gram of curcumin per kilogram…holy cats, that seems like a LOT! Ah no, wait, see my footnote**); 3. the bortezomib alone group, and 4. the curcumin and bortezomib combo group.


25 days after the treatment start date, the mice were killed, and their tumours examined. Skipping the long and detailed explanation of how this process was carried out, let’s get to the results. Compared with the other three groups, the biggest tumours were in the control group, as to be expected. There was instead a significant decrease in tumour volume in both the curcumin and bortezomib groups, i.e., 2 and 3. But in group 4, the combo group, the tumours were even smaller: When examined for tumor volume on different days, we found that curcumin + bortezomib combination was much more effective in reducing the tumor volume compared with either agent alone.


As for thalidomide, the researchers used myeloma cells treated with curcumin in combination either with bortezomib or thalidomide and found that Curcumin potentiated the apoptotic effect of bortezomib from 25% to 85% and thalidomide from 10% to 75%. Not bad at all…


Another interesting titbit, for those who remember my PARP cleavage post: When we examined the poly(ADP-ribose) polymerase cleavage, which indicates caspase-3 activation, a well-known characteristic of apoptosis, we found that curcumin potentiated the effect of bortezomib and thalidomide. In this particular case, curcumin worked better with thalidomide.


Now for the Discussion part: First, cells resistant to chemotherapeutic agents have been shown to express increased activation of NF-kB and suppression of this NF-kB can sensitize the cells to the drug. Second, multiple myeloma cells and mantel cell lymphoma are known to express constitutive active NF-kB that is resistant to bortezomib. Fairly clear, no?


Then we get to an interesting titbit concerning CRP: C-reactive protein, whose expression is regulated by NF-kB, has been shown to enhance the proliferation of myeloma cells and protect myeloma cells from chemotherapy-induced apoptosis both in vitro and in vivo. Among other things, CRP also increases the production of IL-6 with which it works synergistically to protect myeloma cells from chemotherapy-induced apoptosis. Bad stuff…!


Other proteins that help myeloma cells become resistant to the attacks of chemo drugs are cyclin D1, the members of the infamous Bcl family and survivin. I have posted about all of these buggers. At any rate, the study confirms that curcumin down-regulates all of them…as we already knew from previous posts.


Like curcumin, bortezomib inhibits the activation of NF-kappaB, but through different mechanisms. As follows: Bortezomib inhibits the proteasome, resulting in the accumulation of IkBa, whereas curcumin prevents IkB phosphorylation, thus blocking its subsequent ubiquitination and degradation through suppression of upstream kinase IKK. Thus, these different mechanisms of NF-kB suppression provide the rationale for combining these agents to effectively inhibit NF-kB activation. Now, even if we don’t understand the meaning of all this, what is clear is that curcumin and bortezomib attack myeloma cells and reduce NF-kB activity in different ways. And that is exactly why, when combined, they work better than when they are used alone.


Another useful characteristic of curcumin: it can help alleviate fatigue and peripheral neuropathy, which are common side effects of the conventional chemo drugs used to treat myeloma. Indeed, the study states that these effects can be REVERSED by curcumin. No comment needed here, methinks…


The study ends with a very strong statement: In conclusion, the chemoresistance remains a major challenge in the treatment of patients with multiple myeloma as well as other cancers. Multiple myeloma patients who have relapsed after conventional dose chemotherapy or stem cell transplantation are typically treated with high-dose corticosteroids, thalidomide, or bortezomib. However, a large number of these patients do not respond to treatment with these agents. Moreover, prolonged exposure leads to the development of resistance and toxicity, and progression-free and overall survival times for multiple myeloma patients are short. The ability of curcumin to suppress NF-kB activation, down-regulate the expression of cyclin D1 and Bcl-xL, inhibit cell proliferation, potentiate the effects of bortezomib and thalidomide, and overcome chemoresistance provides a sound basis for conducting clinical trials with curcumin, alone or in combination with other agents, to enhance treatment efficacy, reduce toxicity, and overcome chemoresistance of relapsed or refractory multiple myeloma.


*Probably based on the fact that I mention chemo treatments from time to time, especially bortezomib (Velcade), more than a few readers have asked me if I have ever had any conventional treatments. The answer is no. For more on that, please see “My Discovery of Curcumin” page, which, er, needs some updating, for instance I have been taking curcumin for more than three years now, not just two…but anyway, the basic info is there.


**When I first saw that 1 g/kg (or 1000 mg/kg) of curcumin was the daily dose administered to the nude mice in group 2 and 4, I thought that that would translate into a massive amount of curcumin for humans. But then I vaguely recalled that there were differences between mice and humans, other than the, uhm, rather obvious ones. And I remembered that there was a way to convert doses from mice to humans. A bit of research led me to a 2008 study ( dealing with this very topic and providing, yay!, the converting formula. So, unless my math is even worse than I thought (!), based on this formula and a 60 kg human being, 1000 mg/kg x 3 = 3000; 3000 : 37 = 81 x 60 = 4860 mg/daily dose. That means: less than 5 grams of curcumin a day in human terms. So for the past three years plus I have been taking a larger dose of curcumin than was used in this study. Interesting. And finally, an appeal to all my blog-reading math whizzes: would you mind checking my calculations? Thanks! It just seems way too simple, that’s all…

Some dietary flavonoids inhibit Bortezomib

Sherlock (grazieeeee!) sent me a study titled “Dietary flavonoids inhibit the anti-cancer effects of the proteasome inhibitor Bortezomib” (see abstract:, published in the July 16 2008 issue of “Blood.” This is an important study for those who are taking Velcade (Bortezomib) and supplements at the same time, so I decided to read, and post about, the full study. It’s quite a long post, sorry about that!


Quercetin is the most mentioned compound in this study. As you can read on my Quercetin Page, quercetin is a plant chemical, specifically a flavonol, found in apples and red onions and a variety of other foods such as capers, broccoli and red grapes.


In the abstract we can read that quercetin inhibited the killing effect of Bortezomib on primary CLL and malignant B-cell lines. Interestingly, though, when inorganic boric acid (a low toxic substance derived from boron, an element found in rocks, soil and water) was added to the quercetin-Bortezomib combination, this inhibitory effect was diminished. Let me highlight that the cell lines under scrutiny were CLL (=chronic lymphocytic leukaemia) and other malignant B-cell ones.


And what about myeloma cell lines? Well, the researchers found that quercetin had a direct effect on myeloma cells, which sounds like very good news. Indeed, the researchers write, At high doses, quercetin itself induced tumor cell death. Death to myeloma cells? Yippeedadoodee! (Except that I recall reading that we should not take high doses of quercetin, I don’t remember why right at the moment, but I have never taken more than 1.5 grams/day of this supplement, so please be cautious…).


Let’s go on to the full study now. I might as well fess up right at the beginning that I didn’t understand all of it. So I will concentrate on the bits that I did understand. An interesting titbit is that Bortezomib kills CLL cells in vitro but does not display substantial anti-tumor activity in patients with CLL. So Bortezomib has anti-cancer activity in a lab setting but not when administered to CLL patients. Just goes to show that sometimes, unfortunately, in vitro anti-cancer activity cannot necessarily be reproduced in vivo.


The researchers then tell us that Quercetin is one of the most abundant flavonoids in the human diet and is a potent anti-oxidant. In fact, and this is something I did not know, quercetin is the chief dietary flavonol present in the blood. It is also a proteasome inhibitor, as is Bortezomib.


Let’s get to some results. As the abstract anticipated, there is definitely interference between quercetin and Bortezomib as far as CLL cells and other malignant B-cell lines are concerned. Not a good thing, clearly.


Two specific myeloma cell lines were also tested. In order to fight the killing activity of Bortezomib, however, these cells had to be treated with a very high dose of quercetin: Quercetin also had the same inhibitory effect on Bortezomib-induced apoptosis in two myeloma cell lines, U266 and RPMI-8226. However, the myeloma cell lines required higher levels of quercetin (40 micro-M) for maximal inhibition of Bortezomib-induced apoptosis, as compared to 20 micro-M for primary CLL, HRC57 and DoHH2 cells.


Then we read that In addition, myeloma cell lines were more susceptible to quercetin-mediated G2/M arrest compared with the B-lymphoma cell lines. So, in sum, when myeloma cells are “pre-incubated” with a not-too-high-dose of quercetin, their sensitivity to Bortezomib increases, which is a good thing. And another thing: myeloma cells can apparently be killed outright by quercetin, if I understood this part correctly. Of course, in vitro effects may not be the same in vivo, as we know. Proceed with caution, as always.


At any rate, further on we can read a possible explanation for this peculiar occurrence. When quercetin and Bortezomib were added at the same time, the former had an inhibitory effect on the latter. But when myeloma cells were pre-incubated with quercetin, the inhibitory effect was less evident: However, in both myeloma cells lines, pre-incubation with quercetin led to less inhibition on Bortezomib-induced killing, suggesting that myeloma cells are more active in their uptake and utilization of quercetin, thereby reducing the chemical binding between quercetin and Bortezomib. So myeloma cells, unlike CLL cells, gobble up quercetin, which is how the chemical bonding between the two substances can be avoided. Interesting.


I will skip the technical part about Bax activation and go on to a more comprehensible section. (Anyone interested in that part, though, can drop me a line; I would be glad to forward the study.)


The researchers tested other dietary flavonoids, such as myricetin (found in grapes, berries, fruit, veggies, herbs and walnuts), apigenin (in parsley and celery) and kaempferol (in broccoli, tea and grapefruit) , which, like quercetin, are antioxidant compounds possessing anti-proteasome activity. Of these, only myricetin had an inhibitory effect on Bortezomib. Interestingly, its chemical structure is similar to that of quercetin. Makes sense.


The researchers conclude that there are many dietary flavonoids which have similar structures with quercetin or myricetin, so the intake of dietary flavonoids may reduce the killing activity of Bortezomib on circulating leukemic cells.


Other findings: EGCG has an inhibitory effect on Bortezomib, so I probably wouldn’t drink any green tea if I were taking Velcade. I also wouldn’t drink any Cabernet Sauvignon or eat cranberries or Concord grapes, which contain a compound called delphinidin that also inhibits Bortezomib. As does cyanidin, found in many types of berries including grapes, blackberries, blueberries, cranberries, raspberries and cherries; and also in apples and plums.


But there is some GOOD NEWS: curcumin and resveratrol were also tested and found to be okay when taken together with Bortezomib, which confirms what I had read in other studies.


In the Discussion part I found another interesting titbit that is a bit on the technical side (sorry about that!)…here is the full quote: Quercetin and Bortezomib share similarities with respect to proteasome inhibition and the induction of apoptosis. They both can be used in the treatment of cancer. However, the differences between these two compounds are (1) Bortezomib is a boronic dipeptide acid and quercetin is a flavonoid; (2) Bortezomib is a ROS-inducing agent and quercetin is an anti-oxidant. The question is whether they are synergistic or counteract each other in combination. We observed that quercetin prevented Bortezomib-induced ROS generation and apoptosis in primary CLL cells. However, quercetin also blocked Bortezomib-induced apoptosis in B-cell lines in which ROS generation was not evoked. I repeat, this inhibitory effect of quercetin on Bortezomib is true for CLL and other malignant B-cells. Not for myeloma cells.


Further on, we read that, while Bortezomib does not seem to work well for CLL patients, it is highly active in myeloma, another B-lymphoid malignancy, suggesting differential sensitivity to Bortezomib according to tumor type. Also, and this sort of repeats what I have written earlier, myeloma cells pre-incubated with quercetin were not as protected as CLL cells from the apoptotic effect of Bortezomib. The researchers suggest that quercetin (at 20 micro-M) has a direct effect on myeloma cells, but not CLL, HRC57 or DoHH2 cells, to increase sensitivity to, and/or synergize with, Bortezomib.


The researchers add that it is not known if dietary quercetin (i.e., not in supplement form) would interfere with Bortezomib. So CLL patients don’t necessarily have to stop eating apples and onions (the easiest thing to do is ask your doctor). And they also remind us that Not all dietary flavonoids can inhibit Bortezomib. Myricetin showed a similar effect to quercetin on the inhibition of Bortezomib, but kaempferol and apigenin did not.


The study ends as follows: The differential in vivo activity of Bortezomib seen in myeloma and CLL may partly be attributable to the effect of dietary flavonoids: quercetin primes myeloma cells, but not CLL cells, such that they become more sensitive to Bortezomib-induced killing. Further work will elucidate the in vivo significance of these findings, which in turn will inform the need for dietary advice on the intake of flavonoids, as well as drug manipulation of flavonoid activity. 


Hmmm, just as I had written a few concluding sentences and was about to publish this post on my blog, I did a quick online search just for the heck of it and came across a pertinent June 2008 “Haematologica” report ( whose findings made me add the following paragraph.


A group of Korean researchers tested six polyphenols—rutin, quercetin, caffeic acid, gallic acid, EGCG, and tannic acid—discovering that they all inhibited the anti-cancer activity of Bortezomib. Well, we already knew about quercetin and EGCG, so that is nothing new.


Now, the following is mere speculation on my part, but I have the feeling, based on what I understood from the July “Blood” study, that these compounds may have been added to the myeloma cell lines at the same time as Bortezomib, and that might explain the interference.


My point: the Korean study results might have been different if these substances had been added an hour or so before Bortezomib, which would have given the myeloma cells enough time to gobble them up, thus diminishing the interference potential. Pre-incubation with these polyphenols, in other words, might have made the myeloma cells more sensitive to the killing effect of Bortezomib, which would agree with the “Blood” study results. Again, since I have not seen the full Korean report, this is pure speculation on my part.


After reading this abstract, though, I would be concerned if I were taking Velcade and any of the above-mentioned and possibly interfering compounds (not curcumin or resveratrol, I repeat). So, here is my advice to Velcade-takers: please consult your doctor before adding anything to your protocol. Best to be on the safe side.

The dandelion phenomenon, part II

Picking up from where I left off yesterday, the first type of cancer to be linked to stem cells was chronic myeloid leukaemia, or CML. The Johns Hopkins researchers proceed with a lengthy discussion on a drug called imatinib, which is used in CML, but without much success in the long-term. CML patients relapse if they discontinue imatinib (which, the researchers tell us, is currently being used more than interferon-alpha or IFN), or their cancer progresses even while they are on it. There appears to be no survival advantage in taking imatinib. The explanation, the researchers suggest, may lie in the CML stem cell resistance to this drug.

They use the dandelion analogy: “This pattern of activity is analogous to cutting a dandelion off at ground level. Although this will eliminate the visible portion of the weed, the unseen root also needs to be eliminated to prevent regrowth of the weed.”

Contrary to what happens with imatinib, CML patients’ response to the above-mentioned IFN is slow and gradual, “but can be durable.” So IFN would appear to act against the CML stem cells. Then we read “Thus, treatments that selectively attack cancer stem cells will not immediately eliminate the differentiated tumor cells. In this situation, cure (elimination of the cancer stem cells) in effect precedes the clinical demonstration of complete remission (clearance of the differentiated cancer cells) and could occur without actual disease shrinkage.”

This explains why these researchers took such a strong stance against the above-mentioned theory of complete remission. Complete remission may last months or years, but the cancer will return, eventually, unless the cancer stem cells are targeted. A treatment that targets cancer stem cells, however, won’t necessarily affect the circulating non-stem cancer cells. Hence, in this scenario, cure occurs before complete remission. This is contrary to everything I have read on the myeloma patient listservs (where a lot of the focus is on complete remission, or CR as we write it) and in the official myeloma literature. There are heaps of studies on the importance of complete remission in myeloma, in fact.

The researchers go on to discuss bortezomib (marketed as Velcade), a proteasome inhibitor, and lenalidomide (marketed as Revlimid, a derivative of thalidomide) commonly used in the conventional treatment of myeloma. These two drugs “can inhibit myeloma plasma cells but appear to have little activity against myeloma stem cells in vitro,” which means that they are pruning only the visible part of the dandelion, whereas rituximab, a monoclonal antibody, targets myeloma stem cells, i.e., the dandelion’s roots, according to the Johns Hopkins team.

The danger, the researchers point out, is that “As with IFN in CML and rituximab in myeloma, therapy directed against cancer stem cells might be prematurely abandoned if clinical activity is judged solely by criteria that reflect the effects of treatment on the bulk of the cancer.” And in fact, they add,“Not surprisingly, rituximab was found to have limited activity against myeloma in a short-term clinical trial. Rituximab’s activity against myeloma stem cells probably could not have manifested as immediate clinical responses in this trial because of the persistence of the long-lived, but terminally differentiated, myeloma plasma cells.” There you go.

So when we target stem cells, we must be patient. Unfortunately, nowadays, patience is no longer a virtue. We want to see immediate results. Overnight.

The researchers suggest setting up a clinical trial using bortezomib against the bulk of the cancer cells and then rituximab against the myeloma stem cells. Almost two years and a half have passed since this study was published. I went to have a look at the clinical trials being conducted right now. There are 591 trials (!) testing rituximab. I narrowed my search to myeloma, and found that there are 18 trials using rituximab alone or in combination with other drugs, such as lenalidomide or melphalan. Only one study, at the Dana-Farber Cancer Institute, is being conducted with rituximab and bortezomib, but for patients with Waldenstrom’s macroglobulinemia.

Well, these are certainly interesting times. I am all in favour of the dandelion theory, and it is for that reason that I am monitoring the DMAPT clinical trial, which should be beginning soon. (I admit to being more interested in substances such as DMAPT than in rituximab.)

The trees that are slow to grow bear the best fruit. (Molière)