The threat of cancer recurrence

Cancer is a shrewd and highly adaptable disease. It has been outsmarting physicians for an awfully long time. With conventional treatment (chemotherapy, radiation, surgery, targeted therapy, and immunotherapy), the statistics are not good. Of the nearly 2 million people newly diagnosed with cancer last year, over 600,000 of them have already died.

Although treatment outcomes have improved with conventional treatment over the last few decades, there are significant challenges that must be overcome, such as multi-drug resistance, disease progression, metastasis, and often inevitable recurrence. The need for new treatment approaches has never been more urgent.

Why does late-stage cancer recur after complete remission is achieved and there is no evidence of disease? Two big reasons for this are cancer stem cells and senescent cancer cells. If these two cell populations are not dealt with, long-term survival will be difficult if not impossible to achieve.

Cancer stem cells:

In the human body, there are healthy stem cells that help repair and regenerate damaged tissues. Similarly, in tumors, there are cancer stem cells (CSCs) that help repair and regenerate tumors. This subset of cancer cells is also known as tumor-survival cells (TSCs) or tumor-initiating cells (TICs). Cancer stem cells are drug-resistant and remain after each round of chemotherapy to repopulate the tumor with new cancer cells.

Many experts believe that successful eradication of cancer stem cells could change the face of cancer treatment. Not only are cancer stem cells a chief driver of treatment failure, cancer progression, metastasis, and recurrence (often more aggressive), but cancer stem cells may also be the root cause of the original tumor itself. Because of the powerful survival mechanisms of cancer stem cells, chemotherapy, radiation, and surgery are unable to kill them. In fact, conventional therapy may do the opposite and stimulate the proliferation and virulence of cancer stem cells.

Cancer stem cells can migrate and nest in distant sites of the body and remain quiescent (dormant) for months, years, or even decades until the right stimuli come along and awaken them. Conventional therapy can shrink tumors; however, it will not prevent tumor recurrence. Sooner or later, lingering cancer stem cells can form new and often more aggressive tumors from a small number of cells (as few as 100). In other words, being “tumor-free” is not the same as being “cancer-free.” Eradicating tumors is not enough. Cancer stem cells must also be eradicated to achieve long-term survival.

At present, there are no drugs that are FDA-approved for the purpose of targeting cancer stem cells; however, the following supplements and repurposed medications have been found to target cancer stem cells by killing them and/or preventing them from entering a dormant and more resistant state:

Bergamot
Curcumin
Doxycycline + azithromycin + vitamin C
EGCG
Genistein
Resveratrol
Sulforaphane
Tadalafil

Senescent cancer cells:

Besides cancer stem cells, the other problematic cells are senescent cancer cells. Not all cancer cells can be forced into apoptosis (programmed cell death) when treated with chemotherapy, radiation, or hormone-blockers. Instead of dying outright, many cancer cells simply stop proliferating, come to a standstill, and enter a senescent or dormant-like state. This is called senescence-associated growth arrest (SAGA), and while it sounds good, it is accompanied by something bad called senescence-associated secretory phenotype (SASP) in which the senescent cancer cells secrete copious amounts of proinflammatory molecules, protein-degrading compounds, and cancer-promoting growth factors that increase the risk of cancer recurrence.

While it is good that senescent cancer cells do not increase in number as a result of cell growth and cell division like regular cancer cells, in the long run, it is bad because senescent cancer cells do not die and they secrete toxic compounds. These compounds can stimulate cancer stem cells and promote the adverse effects of chemotherapy. If too many senescent cancer cells accumulate, recurrence of cancer can recur.

At present, there are no drugs that are FDA-approved for the purpose of targeting senescent cancer cells; however, the following supplements and repurposed medications have been found to eradicate senescent cells or decrease the toxic secretions of those senescent cells that cannot be eradicated:

Apigenin
Dasatinib + quercetin
Fisetin
FOXO4-DRI
Melatonin
Rapamycin
Tocotrienols

Comments from Dr. Thomas: If you are currently being treated for cancer or are in remission, it is crucial that you ask your oncologist what is being done to target your cancer stem cells and senescent cancer cells. Failing to do so could threaten your life.

References:

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