VIDEO: Neil Riordan, PA, PhD discusses Stem Cells: Their Role in Aging and in the Treatment of Chronic Diseases

At our May 4th 2019 event in Southlake, Texas, Dr. Riordan discusses stem cell therapy at the Stem Cell Institute in Panama City, Panama. He mentions the two main types of adult stem cells but his talk focuses on mesenchymal stem cells including their sources and functions. Then he goes on to discuss specifically the specially selected human umbilical cord tissue-derived MSCs used in Panama. He highlights several clinical trials for spinal cord injury, rheumatoid arthritis, diabetes and cancer inhibition. He shows MSCs growing in culture and discusses 3D culturing. He then goes into cord tissue products being offered in the US including Signature Cord, a minimally-manipulated Wharton’s jelly product he developed. Finally, Dr. Riordan discusses current US law and the new stem cell law in Texas, including where he sees the industry in the US going from here.

High-Dose Intravenous Vitamin C Therapy at Riordan Clinic Offers New Hope to Young Cancer Patient After Chemotherapy Fails


Hoyt Lee

Hoyt Lee

After undergoing failed chemotherapy treatments and the debilitating side effects that go along with them, things are finally looking up for 6 year-old cancer patient, Hoyt Lee. Since starting high-dose intravenous vitamin C therapy at the Riordan Clinic in Wichita, Kansas two and a half years ago, Hoyt’s condition stabilized and is now improving; something his oncologists said would likely never happen.

At just three months of age, doctors diagnosed Hoyt Lee with Neurofibromatosis 1 (NF-1). At 16 months old, he started chemotherapy for a brain tumor. After completing a grueling year of drug cocktails that wracked his young body, Hoyt’s mother, Shawna Overbey, received the news that she’d feared the most. Hoyt’s tumors were not responding to the chemo. They were growing.
Magnetic Resonance Imaging (MRI) showed accelerated tumor growth in his optic nerve chiasm. The optic chiasm is an X-shaped structure formed by the crossing of the optic nerves in the brain. The tumor was affecting his right and left eyes, his pituitary gland, and his hypothalamus.

The only available treatment alternatives were radiation or a different chemotherapy cocktail that can cause nerve damage and affect motor skills like walking and hand movement.

That’s when Shawna knew there had to be another way. Countless hours of research lead Shawna and Hoyt to Dr. Ron Hunninghake at the Riordan Clinic, a non-profit organization in Wichita, Kansas that specializes in alternative cancer therapies. The Riordan Clinic was founded in 1975 by Dr. Hugh Riordan and benefactor Olive W. Garvey. It has been providing IV therapy to patients like Hoyt for the past 40 years.

The late Dr. Riordan and his son, Neil H. Riordan, PhD, were pioneers in the use of vitamin C to treat cancer. Far ahead of their time, they invented patents (6,448,287, 6,436,411, 6,284,786) on treating cancer with vitamin C that date back prior to the turn of this century. For the past 20 years, Nina Mikirova, PhD has carried on their cancer research at the clinic.

At present, Neil Riordan, PhD is a renowned applied stem cell therapy researcher whose clinic in Panama, Stem Cell Institute, specializes in treating inflammatory and autoimmune related conditions with human *umbilical cord tissue–derived mesenchymal stem cells. Dr. Riordan has also teamed up with board-certified orthopedic surgeon, Wade McKenna, DO to bring stem cell therapy for orthopedic conditions to Southlake, Texas at the Riordan-McKenna Institute (RMI). RMI uses a proprietary mixture of the patient’s own bone marrow stem cells with *amniotic tissue products. Patients can receive intravenous high-dose vitamin C and other intravenous nutritional supplements at Riordan Wellness, which occupies space at the RMI building in Southlake.

Decades after the Riordans’ pioneering research, ascorbic acid treatment for cancer is entering the mainstream, with clinical trials being conducted at John’s Hopkins, University of Iowa, Jefferson University and Cornell. A clinical trial on vitamin C and prostate cancer was recently completed at Copenhagen University Hospital at Herlev, Denmark and in a study published November 5th in Science, a team of researchers from Weill Cornell Medicine, Cold Spring Harbor Laboratory, Tufts Medical Center, Harvard Medical School and The Johns Hopkins Kimmel Cancer Center found that high doses of vitamin C – roughly equivalent to the levels found in 300 oranges – impaired the growth of KRAS mutant and BRAF mutant colorectal tumors in cultured cells and mice.

Since undergoing IV high-dose vitamin C therapy, Hoyt Lee’s progress has been miraculous. According to his mother, MRIs have shown tumor stability or shrinkage over the past two and a half years. The tumor is no longer affecting his right eye, pituitary gland or hypothalamus. As of February 2016, there is almost no sign of a tumor in Hoyt’s optic nerve chiasm. Hoyt is doing so well that he won’t have to return to the hospital for another year.

“As Schopenhauer said, ‘All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.’,” said Dr. Riordan. “As far as high-dose vitamin C goes, I think that, fortunately, we are finally entering the third stage,’ he added.

“We are delighted with Hoyt’s progress and equally proud that through generous charitable contributions, we’ve been able to do it without the crushing costs that can be associated with conventional treatments like chemotherapy,” commented Donna Kramme, CEO of Riordan Clinic. “It can cost as much as $15,000 per year to treat a child like Hoyt. We ask that everyone who is passionate about helping children like Hoyt please contact the Riordan Clinic to donate today. Without your help we cannot continue vital research that will make Hugh Riordan’s dream four decades ago, a reality today and into the future,” she concluded.

About Riordan Clinic

Riordan Clinic is a not-for-profit 501(c)(3), nutrition-based health facility in Wichita, Kansas. We have integrated lifestyle and nutrition to help you find the underlying causes of your illness. Since our inception in 1975, our mission has been clear and unwavering. Our functional medicine providers “stimulate an epidemic of health.”

People turn to the Riordan Clinic to restore, improve, and maintain health. Our integrative health practitioners listen to the needs of patients. Then we test and measure to map out a research-based, nutrition-fueled path to well being. Together, our professionals move beyond simply treating symptoms to address illness at its cause. Your Way to Well communicates a positive, hope-filled message. It stresses our individualized approach and achieves the best possible outcomes.

Riordan Clinic Website:

Riordan Clinic
3100 N. Hillside Ave.
Wichita, Kansas

Tel: (316) 682-3100
Fax: (316) 682-2062

About Riordan-McKenna Institute (RMI)

RMI specializes in non-surgical treatment of acute and chronic orthopedic conditions using *amniotic tissue allograft and bone marrow aspirate concentrate (BMAC) that is harvested using the patented BioMAC bone marrow aspiration cannula. Common conditions treated include meniscal tears, ACL injuries, rotator cuff injuries, runner’s knee, tennis elbow, and joint pain due to degenerative conditions like osteoarthritis.

Additionally, RMI augments orthopedic surgeries with BMAC and amniotic tissue allograft to promote better post-surgical outcomes and uses amniotic membranes as part of a complete wound care treatment regimen.

BMAC contains a patient’s own mesenchymal stem cells (MSC,) hematopoietic stem cells (CD34+), growth factors and other progenitor cells. Amniotic tissue allograft is composed of collagens and other structural proteins, which provide a biologic matrix that supports angiogenesis, tissue growth and new collagen during tissue regeneration and repair.
*Amniotic tissue is donated after normal healthy births.

Riordan-McKenna Institute Website:

Riordan-McKenna Institute
801 E. Southlake Blvd.
Southlake, Texas

Tel: (817) 776-8155
Toll Free: (877) 899-7836
Fax: (817) 776-8154

About Stem Cell Institute Panama

Founded in 2007 on the principles of providing unbiased, scientifically sound treatment options; the Stem Cell Institute (SCI) has matured into the world’s leading adult stem cell therapy and research center. In close collaboration with universities and physicians world-wide, our comprehensive stem cell treatment protocols employ well-targeted combinations of autologous bone marrow stem cells, autologous adipose stem cells, and donor human umbilical cord stem cells to treat: autism, cerebral palsy, multiple sclerosis, spinal cord injury, osteoarthritis, rheumatoid arthritis, heart disease, and autoimmune diseases.

In partnership with Translational Biosciences, a subsidiary of Medistem Panama, SCI provides clinical services for ongoing clinical trials that are assessing safety and signs of efficacy for autism, multiple sclerosis, osteoarthritis, rheumatoid arthritis, and spinal cord injury using allogeneic umbilical cord tissue-derived mesenchymal stem cells (hUC-MSC) and hU-MSC-derived mesenchymal trophic factors (MTF). In 2017, Translation Biosciences plans to expand its clinical trial portfolio to include heart disease and cerebral palsy.

For more information on stem cell therapy:

Stem Cell Institute Website:

Aquilino de la Guardia Street
BICSA Financial Center
63rd Floor
Panama City, Panama

*Tissue is donated after normal, healthy births.

FDA poised to outlaw breast reconstruction for breast cancer survivors using their own fat tissue

FDA-NotApprovedStampThe U.S. Food and Drug Administration held public hearings for two days this week to allow for public commenting on proposed guidance relating to the regulation of human cells, tissues or tissue-based products.

In its current form, this guidance will classify a woman’s own fat tissue as a drug when used in breast reconstruction procedures. This is certainly bad news for the over 100,000 female cancer patients who seek this procedure each year.

According to the FDA, the sole purpose of a woman’s breast is to lactate. Of course that begs the question of what the purpose of a man’s breast might be but we will leave that for another day. Since fat from other parts of the body does not produce milk, it cannot be transferred into a woman’s breast.

Specifically, in its industry guidance entitled Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps) from Adipose Tissue: Regulatory Considerations; Draft Guidance, the FDA states, “The basic function of breast tissue is to produce milk (lactation) after childbirth. Because this is not a basic function of adipose [fat] tissue, using HCT/Ps from adipose tissues for breast augmentation would generally be considered a non-homologous use.” “Homologous use” refers to a tissue’s ability to serve the same “basic function or functions” as the tissue into which it is being transplanted. So in this case, “non-homologous” use equals FDA-regulated “drug”.

That’s right ladies. Your fat tissue is an FDA-regulated drug if your doctor wishes to use it to help reconstruct your breasts following a mastectomy unless she goes through the FDA drug approval process, which can take a decade or two and cost upwards of 2 billion dollars. Needles to say, this is a financial burden that no doctor, clinic or hospital can bear. Once finalized, this new guidance will effectively shut the door on using a woman’s own fat tissue to help reconstruct her breasts.

And it doesn’t stop there. According to the FDA, in most cases, our own cells are drugs too. An FDA panel member even went so far as to state that our blood is an FDA-regulated drug.

For example, if your doctor wants to remove a small sample of bone marrow from your hip and inject part of it into your knee because she has read the literature and believes it can help you heal without surgery, the FDA says that’s verboten because you guessed it – it’s a drug that is subject to the full FDA drug approval process.

As the FDA becomes increasing intrusive in our lives, restricting the ability of licensed medical doctors to practice medicine, one has to wonder where it all will end? The answer seems to be that once the FDA has its way, our bodies, down to the very last cell, will be classified as drugs, and therefore subject to federal regulation by the FDA.

If you agree that the FDA has no business outlawing the use of your own fat tissue to reconstruct your breasts, please spread the word and ask your friends, family members and doctors to let the FDA know what you think before September 27th by commenting here:

You might also consider contacting your local congressman, congresswoman, and state senators.

2016-09-15T16:40:41+00:00September 15th, 2016|Bone Marrow Stem Cells, Breast Cancer, Cancer, FDA, News|

Modulation of Cytokines in Cancer Patients by Intravenous Ascorbate Therapy

IV-Vitamin-CNina Mikirova, Neil Riordan, Joseph Casciari

Med Sci Monit 2016; 22:14-25
DOI: 10.12659/MSM.895368

BACKGROUND: Cytokines play an important role in tumor angiogenesis and inflammation. There is evidence in the literature that high doses of ascorbate can reduce inflammatory cytokine levels in cancer patients. The objective of this study was to investigate the effect of treatment by intravenous vitamin C (IVC) on cytokines and tumor markers.

MATERIAL AND METHODS: With the availability of protein array kits allowing assessment of many cytokines in a single sample, we measured 174 cytokines and additional 54 proteins and tumor markers in 12 cancer patients before and after a series of IVC treatments.

RESULTS: Presented results show for our 12 patients the effect of treatment resulted in normalization of many cytokine levels. Cytokines that were most consistently elevated prior to treatments included M-CSF-R, Leptin, EGF, FGF-6, TNF-α, β, TARC, MCP-1,4, MIP, IL-4, 10, IL-4, and TGF-β. Cytokine levels tended to decrease during the course of treatment. These include mitogens (EGF, Fit-3 ligand, HGF, IGF-1, IL-21R) and chemo-attractants (CTAC, Eotaxin, E-selectin, Lymphotactin, MIP-1, MCP-1, TARC, SDF-1), as well as inflammation and angiogenesis factors (FGF-6, IL-1β, TGF-1).

CONCLUSIONS: We are able to show that average z-scores for several inflammatory and angiogenesis promoting cytokines are positive, indicating that they are higher than averages for healthy controls, and that their levels decreased over the course of treatment. In addition, serum concentrations of tumor markers decreased during the time period of IVC treatment and there were reductions in cMyc and Ras, 2 proteins implicated in being upregulated in cancer.

Read Full Article…

2016-02-15T17:06:37+00:00February 15th, 2016|Cancer, Neil Riordan, News, PhD|

The dual effect of MSCs on tumour growth and tumour angiogenesis

Michelle Kéramidas, Florence de Fraipont, Anastassia Karageorgis, Anaïck Moisan, Virginie Persoons, Marie-Jeanne Richard, Jean-Luc Coll and Claire Rome

Abstract (provisional)

Understanding the multiple biological functions played by human mesenchymal stem cells (hMSCs) as well as their development as therapeutics in regenerative medicine or in cancer treatment are major fields of research. Indeed, it has been established that hMSCs play a central role in the pathogenesis and progression of tumours, but their impact on tumour growth remains controversial.

Our results suggest that hMSCs injection decreased solid tumour growth in mice and modified tumour vasculature, which confirms hMSCs could be interesting to use for the treatment of pre-established tumours.


In this study, we investigated the influence of hMSCs on the growth of pre-established tumours. We engrafted nude mice with luciferase-positive mouse adenocarcinoma cells (TSA-Luc+) to obtain subcutaneous or lung tumours. When tumour presence was confirmed by non-invasive bioluminescence imaging, hMSCs were injected into the periphery of the SC tumours or delivered by systemic intravenous injection in mice bearing either SC tumours or lung metastasis.


Regardless of the tumour model and mode of hMSC injection, hMSC administration was always associated with decreased tumour growth due to an inhibition of tumour cell proliferation, likely resulting from deep modifications of the tumour angiogenesis. Indeed, we established that although hMSCs can induce the formation of new blood vessels in a non-tumoural cellulose sponge model in mice, they do not modify the overall amount of haemoglobin delivered into the SC tumours or lung metastasis. We observed that these tumour vessels were reduced in number but were longer.


Our results suggest that hMSCs injection decreased solid tumour growth in mice and modified tumour vasculature, which confirms hMSCs could be interesting to use for the treatment of pre-established tumours.

Original Link:

2013-04-30T18:17:29+00:00April 30th, 2013|Cancer, Mesenchymal Stem Cells, News, Stem Cell Research|

Resveratrol Suppresses Cancer Stem Cells

Pandey et al. Breast Cancer Res Treat.

Resveratrol is a compound found in grapes, red wine, purple grape juice, peanuts, and berries that has been associated with many health benefits, particularly reduction in heart disease. Some studies have demonstrated that resveratrol increases life span when administered at high concentrations. One area of controversy has been the potential of resveratrol in the treatment of cancer.

One way of testing the anti-cancer efficacy of compounds is to administer the compound of interest to cancer cells that are growing “in a test tube”, or “in vitro.” Recently it was shown that cancer cells taken from a patient and propagated in vitro are usually not representative of the original tumor from which the cancer cells were excised. Specifically, it has been shown that in patients, cancer cells can broadly be classified into the rapidly multiplying cells, and the “sleeping cells” otherwise known as tumor stem cells. It appears that in vitro the rapidly multiplying cells continue multiplying, but the cancer stem cells do not multiply. This is important because the cancer stem cells seem to be the cells responsible for causing the tumor to spread, whereas in the rapidly multiplying cells actually seem to be weaker and more sensitive to chemotherapy.

To date the majority of studies investigating effects of resveratrol on cancer have focused on testing with the rapidly multiplying cells. The paper published today investigated the effects of resveratrol on tumor stem cells. Breast cancer tumor stem cells where isolated based on expression of the proteins CD44 and ESA, and lacking CD24. Tumor stem cells were harvested from patients that were both estrogen receptor positive and negative. It was found that addition of resveratrol caused death of the tumor stem cells, as well as blocked their ability to form three dimensional tumors in tissue culture called “mammospheres.”

Interestingly it seemed like the effects of the resveratrol were mediated by manipulating the way in which the cancer stem cells make fat. Specifically, resveratrol caused a significant reduction in fat synthesis which is associated with down-regulation of the enzyme fatty acid synthase (FAS). The suppression of the enzyme FAS was correlated with upregulation of the genes DAPK2 and BNIP3, which are known to stimulate a process called “apoptosis”, or cellular suicide.

This recent paper belongs to a growing example of scientific reports in which various “treatments” advocated by naturopathic doctors seem to have effects on cancer stem cells. For example, a previous publication (Kakarala et al. Targeting breast stem cells with the cancer preventive compounds curcumin and piperine. Breast Cancer Res Treat. 2010 Aug;122(3):777-85.) reported that the chemical curcumin, which is a component of the Indian spice turmeric, selectively inhibits cancer stem cells.

It appears that many of the chemotherapeutic drugs that are conventionally used in the treatment of cancer do not affect the cancer stem cell because chemotherapy requires tumor cells to be actively proliferating. In contrast, many of the “natural remedies” seem to suppress cancer stem cells because their activities seem to be mediated by other means than the ones in which chemotherapy works. It will be interesting to see if more papers such as the present one appear, which seem to provide scientific rationale for a more “compassionate approach” to cancer therapy

2010-12-29T14:23:41+00:00December 29th, 2010|Cancer, News, Stem Cell Research|

Pluripotent stem cell-derived natural killer cells for cancer therapy.

Knorr et al. Transl Res. 2010 Sep;156(3):147-154. Epub

Immune therapy of cancer is an exciting prospect given the possibility of treating cancer without the side effects associated with conventional treatments such as chemotherapy or radiotherapy. Additionally, the use of the immune system to target tumors offers the possibility of eradicating micrometastasis, which often cannot be treated by conventional means.

Early work in the immunotherapy of cancer involved taking out patient lymphocytes that were infiltrating the tumor, expanding them outside of the body, and subsequently re-injecting them with the hope that expanded numbers of tumor-specific killer cells would destroy the tumor. Unfortunately this approach was very expensive and did not yield positive results to justify the complexity and expense of the procedure. One possible reason for the failure of this approach is that the cells used where already “old” and “exhausted”. In other words, previous encounters of the T cells with cancer antigens seems to have programmed them so as to inhibit ability to mount a proper immune response.

The use of natural killer cells as an alternative to T cells was considered. These cells, called lymphokine activated killers (LAK) displayed specific ability to kill tumors and were more effective than T cells alone. Unfortunately this approach too also required substantial manipulation of the cells outside of the body and was not practical.

In a recent paper, the group of Knorr et al discussed how to use stem cells to solve the problem of generating anti-cancer immune cells out of the body. They discuss how they have successfully used embryonic stem cells to generate “universal donor” natural killer cells. This approach is highly promising since NK cells do not need to be matched with the recipient in order to mediate anti-cancer activity. Additionally, since the cells are generated “brand new” in the laboratory, the problem of “exhaustion” is no longer relevant. Unfortunately there are still several obstacles to overcome such as the potential of embryonic stem cells forming leukemias/tumors, and the possibility of host anti-graft responses.

The paper also describes the future possibility of using inducible pluripotent stem (iPS) cells as a method of generating autologous T cells with any given TCR specificity.

2010-08-01T16:46:36+00:00August 1st, 2010|Cancer, News, Stem Cell Research|

Natural Compound in Broccoli Slows Breast Cancer Stem Cells

The area of cancer stem cells is very hot. To give an
example, the pharmaceutical company GSK recently purchased the cancer stem cell
company Oncomed for more than a billion dollars, at a time when Oncomed’s cancer
stem cell-targeting drugs were not even tested in humans. This area is of great
interest because it suggests that the way to kill cancer is not to block the
fast multiplying cells, but that the cancer has a "root cause" that scientists
for decades have been ignoring.

Cancer stem cells are usually not destroyed by chemotherapy
or radiation therapy because they are slow dividing cells that possess numerous
proteins to protect themselves from toxicity such as multiple drug resistance
proteins. These proteins have the function of identifying chemotherapy inside
of the cancer cell and actively pumping it out. It is believed that the reason
why these proteins exist is to protect cells from damage to DNA. In cancer stem
cells these proteins appear to play a role in causing relapse after

Previously it was reported that the chicken feed antibiotic
salinomycin has the ability to selectively kill cancer stem cells (Gupta PB.
Identification of selective inhibitors of cancer stem cells by high-throughput
screening. Cell. 2009 Aug 21;138(4):645-59. Epub 2009 Aug 13
), additionally,
using similar testing scenarios researchers found the anti-diabetic drug
metfomin inhibits breast cancer stem cells (Vazquez-Martin et al. The
anti-diabetic drug metformin suppresses self-renewal and proliferation of
trastuzumab-resistant tumor-initiating breast cancer stem cells. Breast Cancer
Res Treat. 2010 May 11
). Given the recent nature of these findings, their
use in humans has not yet been reported in the scientific literature. In the
current study which will be discussed, another compound with similar anti-breast
cancer stem cell activity was identified.

A recent study (Li et al. Sulforaphane, a dietary
component of broccoli/broccoli sprouts, inhibits breast cancer stem cells. Clin
Cancer Res. 2010 May 1;16(9):2580-90
) demonstrated that a natural chemical
compound found in broccoli and other cruciferous vegetables called sulforaphane
has the ability to slow down multiplication of breast cancer stem cells.
Essentially this means that sulforaphane can block the cells that cause cancer
from being activated and thus could be an effective cancer therapy if high
enough doses can be safely administered.

The scientists purified human breast cancer stem cells
using the Aldefluor assay made by the company Aldagen, which selects for cells
expressing the enzyme aldehyde dehydrogenase, an enzyme found in normal and
cancer stem cells. The stem cells were tested to see if they would form tumors
in mice lacking an immune system called nonobese diabetic/severe combined
immunodeficient mice.

It was found that sulforaphane administered at a
concentration of 1-5 micromol/L was sufficient to suppress multiplication of the
aldehyde dehydrogenase-positive stem cell population by 65% to 80% and reduce
the size and number of primary mammospheres by 8- to 125-fold and 45% to 75%,
respectively. Mammospheres are round tumor-like structures that grow in tissue
culture plates that represent a three-dimensional cancer.

Daily injection with 50 mg/kg sulforaphane for 2 weeks
reduced aldehyde dehydrogenase-positive cells by >50% in nonobese
diabetic/severe combined immunodeficient xenograft tumors. Since it appeared
that the administration of sulforaphane eliminated breast cancer stem cells in
the animal, the next step was to assess the ability of the growing tumors to
cause secondary tumors when transplanted into other animals. This indeed was
demonstrated to be the case. Ability to block transfer of tumors to secondary
recipients is associated with possibility of cure since it represents targeting
of the functional tumor stem cell compartment.

Mechanistically it appears that sulforaphane works on the
cancer stem cells through suppression of the Wnt/beta-catenin self-renewal
pathway, which is found in numerous tumor and non-malignant stem cells. This of
course poses the question of whether the high doses of sulforaphane that were
used in the study would have unwanted effects on healthy stem cells in the
body. The most relevant side effect of chemotherapeutic drugs is suppression of
blood cell production from the bone marrow stem cell. Indeed the scientists
found that there was no alteration of blood cell parameters in treated animals,
suggesting at least a partial degree of selectivity.

Sulforaphane is believed to exert at least some of its
anticancer biological effects through its ability to suppress histone
deacetylase (HDAC) activity. HDAC are proteins that are involved in "bundling"
of the DNA. If DNA from one cell was stretched out, it would be 7 meters from
end-to-end. The histone that are acetylated bind DNA in a loose manner and
allow for new genes from the DNA to be expressed that normally would not be
expressed. In the area of cancer, the treatment with HDAC inhibitors is
believed to cause brand new expression of tumor suppressor genes. These genes,
such as p53, instruct the tumor cell to undergo cellular suicide, called

The controversial "Burzynski Therapy" involving
antineoplastons, which are naturally occurring compounds is believed to function
through induction of histone acetylation and induction of tumor suppressor genes
(Burzynski, The present state of antineoplaston research, Integr Cancer Ther.
2004 Mar;3(1):47-58). It would be interesting to examine whether some of the
reported positive effects of this non-toxic cancer therapy is mediated by
suppression of tumor stem cell activity.

A recent paper (Ho et al. Dietary sulforaphane, a
histone deacetylase inhibitor for cancer prevention. J Nutr. 2009
Dec;139(12):2393-6. Epub 2009 Oct 7
) demonstrated that sulforaphane inhibits
HDAC activity in human colorectal and prostate cancer cells. Based on the
similarity of sulforaphane metabolites and other phytochemicals to known HDAC
inhibitors, it was previously demonstrated that sulforaphane acted as an HDAC
inhibitor in the prostate, causing enhanced histone acetylation, derepression of
P21 and Bax, and induction of cell cycle arrest/apoptosis, leading to cancer
prevention. The possible ability of sulforaphane to target aberrant acetylation
patterns, in addition to effects on phase 2 enzymes, may make it an effective
agent in suppressing cancer cells in a non-toxic manner.

This study also poses the question if HDAC inhibitors in
general can alter tumor stem cell ability. It is known that valproic acid, the
HDAC inhibitor actually increases ability of stem cells to self renew while
being selectively toxic to leukemic cells

An interesting note regarding cancer stem cells is that many approaches
traditionally supported by practitioners of alternative medicine may actually be
targeting these cells. In alternative medicine the main theme is providing the
body with nutrients to "heal itself". Practitioners of alternative medicine
have had some degree of success treating cancer in a "nontoxic" manner using
dramatic dietary modifications, nutrient therapy, and administration of agents
that induce differentiation. It may be possible that these interventions act to
reduce the localized inflammation in the tumor mass. This inflammation is
believed by some to be what stimulates the cancer stem cell to enter cell
cycle. Accordingly, it is interesting to see that components of broccoli
inhibit cancer stem cells. It will be interesting to examine other nutrients
for ability to target cancer stem cells.

2010-05-11T17:37:08+00:00May 11th, 2010|Cancer, News, Stem Cell Research|