- Proteolytic enzymes are naturally occurring proteins that break down other proteins
- As a therapy for CFCs (Cancer) proteolytic enzymes have been successfully used to alleviate treatment and illness-induced symptoms, enhance other therapies, and improve survival outcomes
- Mechanisms behind anti-CFC effects include:
- Breaking down tumor tissue to improve treatment efficacy, especially useful for dense tumors such as pancreatic CFCs
- Reducing inflammation
- Exposing CFCs to the immune system’s attack by degrading their protective surface proteins
- Directly eliminating CFCs by eliminating CFC stem cells.
What Are Proteolytic Enzymes?
Proteolytic enzymes, or proteases, are proteins that break down other proteins by catalyzing the hydrolysis of peptide bonds. They are involved in essential cellular processes such as digestion, protein recycling, tissue remodeling, immune defense, and inflammation regulation across all living organisms.
People have unknowingly used proteolytic enzymes as part of traditional medicine for centuries, as they are important active ingredients in many medicinal plants. The most utilized and studied proteolytic enzymes are derived from extracts of plant, animal and microbes:
- Bromelain (pineapple)
- Papain (papaya)
- Ficin (fig leaf)
- Trypsin and Chymotrypsin (animal pancreatic enzymes)
- Nattokinase, Lumbrokinase, Serratiopeptidase (microbial sources)
When taken orally in extracted forms, some enzymes bypass the body’s usual processes of digestion through what is known as oral tolerance and are absorbed through the digestive tract, enter the bloodstream, where they retain their proteolytic properties, and exert wide systemic effects such as:
- Eliminate infections: Proteolytic enzymes can kill various microorganisms, including bacteria, viruses, fungi, and parasites. Enzymes can also break down protective biofilm layers produced by microbes to protect themselves from being destroyed.
- Resolve inflammation: By modulating small proteins called cytokines produced by the body that are intended to regulate a wide range of biological processes including inflammation, proteolytic enzymes are able to reduce chronic inflammation while supporting tissue repair. They have been successfully used in treating pain, wounds, injuries, arthritis and in support of exercise recovery.
- Enhance digestion and nutrient absorption: When taken with food, supplemental proteolytic enzymes assist in the digestion of protein.
In addition to all of the aforementioned actions, proteolytic enzymes are able to directly eliminate or are synergistic with other therapies and lifestyle interventions to eliminate CFCs.
Historical Origins of Enzyme Therapy in CFCs (Cancer)
The concept of enzyme therapy as a treatment for CFCs developed over 100 years ago from observations of several researchers. The idea was first proposed by British embryologist John Beard in 1902. His trophoblast theory suggested that CFC behave like embryonic trophoblasts, the rapidly growing cells that form the outer layer of the early embryo and contribute to placenta formation.
The placenta is the point of attachment between the developing fetus and the mother’s uterus. This is where the mother’s blood connects with that of the embryo’s, laden with the end products of metabolism such as carbon dioxide and other waste products and are replaced with mother’s nutrient and oxygen rich blood. Once the embryo’s pancreas begins producing proteolytic enzymes like trypsin and chymotrypsin at around day 56, the trophoblast cells stop dividing and a stable placenta is formed. Beard posited that CFCs results from trophoblast cells that have escaped this regulatory control, and he went on to discover that pancreatic enzymes could halt the growth of CFCs and restore the original functioning of the cells.
Beard’s trophoblast model of CFCs states 1) adult stem cells are ectopic (escaped) trophoblast cells that had migrated to other tissues early in embryogenesis; 2) pancreatic enzymes convert the trophoblast into a stable placenta; 3) CFCs arise from trophoblasts that have escaped regulatory control; and 4) pancreatic enzymes can effectively be used to treat CFCs.
Beard treated over 170 patients with fresh pancreatic extracts and reported both tumor shrinkage and long-term improvement in some cases. However, Beard’s findings were largely dismissed by other scientists as they failed to repeat his results, possibly because they used stored extracts that had lost their activity.
Further support for Beard’s theory came in 1925 when researchers Freund and Kaminer found that blood from healthy individuals could destroy CFCs, while CFC patients’ blood could not, until proteolytic enzymes were added. This led to the development of systemic enzyme therapy, later advanced by Dr. Max Wolf, Dr. William Kelley, and others.
Interestingly, modern research has discovered aspects in CFCs that make Beard’s old trophoblast theory relevant to current model. It is now known that tumors contain small populations of CFCs (cancer) stem cells. CFC stem cells can generate and maintain tumors, and they likely originate from normal stem cells, aligning with Beard’s theory of stem-cell-like origin of CFCs. They are also resistant to chemotherapy and radiation, making them primary targets for therapies.
Benefits and Mechanisms of Proteolytic Enzymes in CFC (Cancer) Therapy
Proteolytic enzymes have been successfully used both as enhancers of other treatments and even as standalone therapy. They have shown significant improvements in survival outcomes, alleviating symptoms, supporting immune function, disrupting tumor structure, and even targeting CFC (cancer) stem cells.
1. Reducing Side Effects of Chemotherapy, Radiation and Surgery
- Animal and human studies show enzymes can reduce organ damage, fibrosis and peripheral neuropathy from chemotherapy
- In clinical trials enzyme therapy reduced radiation-related symptoms such as pain, skin reactions, and subcutaneous tissue changes in people with cervical and head and neck CFCs
- Enzyme supplements speed up post-surgery wound healing
- Enzymes accelerate healing by dissolving dead tissue, clearing up inflammatory cytokines, and improving blood and lymphatic flow
2. Modulating Inflammation and Immune Responses
Chronic inflammation fuels CFC development and progression. Proteolytic enzymes show context-dependent immune-modulating effects, meaning they reduce inflammation while supporting immune responses against tumors:
- Enzymes reduce tumor-promoting inflammation by suppressing pro-inflammatory signaling (NF-κB, COX-2, IL-6) while enhancing immune function (promoting IFN-γ signaling)
- In people with breast CFCs oral enzyme therapy stimulated deficient immune cell (monocytes) activity, restoring immune function closer to normal levels.
- In a study on healthy people, enzyme therapy significantly enhanced the anti-tumor function of polymorphonuclear leukocytes (PMN), essential immune cells in the defense against CFCs. When PMN encounter CFCs, they kill them by generating reactive oxygen species (ROS), a process known as “respiratory burst”. Enzyme therapy enhanced ROS generation in a dose-dependent manner (peak with 20 tablets, 4 hours after ingestion), aligning with typical clinical dosing of 10–20 tablets per day.
3. Enhancing Other Treatments by Reducing Tumor Stiffness
Several enzymes have been shown to synergize with chemotherapy, radiotherapy, and immunotherapy due to their unique ability to modify tumor tissue. Tumors are typically rich in structural molecules including fibrin, collagen, mucins, and hyaluronic acid, that form a dense matrix and a significant physical barrier for therapies as well as immune cells to enter the tumor. In addition, weak blood flow in tumors creates a low oxygen (hypoxic), acidic, and inflammatory environment. This abnormal environment is responsible for turning on genes that promote aggressive growth and treatment resistance and suppressing immune responses.
Proteolytic enzymes degrade tumor matrix components (fibrin, collagen, mucins, hyaluronic acid), improving:
- Oxygenation and blood flow
- Drug delivery and radiotherapy effectiveness
- Immune cell infiltration
In an animal study with pancreatic CFCs, that are notoriously hard to treat due to the dense tumor structure, a combination of bromelain and N-acetyl cysteine (NAC, an antioxidant that can reduce the disulfide bonds found within a mucinous mass):
- Reduced tumor density
- Was as effective as Gemcitabine (a standard chemotherapy drug) in reducing tumor growth
- Allowed for over 99% dose reduction of Gemcitabine with the same efficacy
- Had no observable toxicity even at high doses allowing continuous treatment
- Even when injected into the abdominal cavity, tumor growth slowed down in distant untreated locations, showing systemic tumor suppressive effects
4. Systemic Anti-Tumor Effects
In addition to breaking down established tumors, proteolytic enzymes degrade circulating proteins that CFCs use when they enter bloodstream. CFCs circulating in blood coat themselves with fibrin and platelets to penetrate distant tissues and prevent immune cells from recognizing and attacking them.
Enzymes such as bromelain and nattokinase have been shown to:
- Break down fibrin
- Inhibit platelet-tumor interactions
This, then exposes CFCs to the immune system thus reducing their metastatic potential.
5. Selectively Targeting CFCs and Their Stem Cells
Proteolytic enzymes have been shown to kill CFCs in a targeted manner, without harming healthy cells. They promote cell death (apoptosis) in CFCs by influencing their cellular signaling, upregulating pro-apoptotic proteins (p53, Bax) and downregulating survival pathways (Akt, ERK). In healthy cells, however, they show opposite, protective effects enhancing cellular resilience and survival under stress.
Even more importantly, proteolytic enzymes inhibit epithelial–mesenchymal transition (EMT), a process wherein epithelial cells or mature cells are transformed into mesenchymal cells (stem cells). Fundamentally, this involves epithelial cells losing their apical–basal (top-to-bottom) polarity and cell–cell adhesion by disrupting tight junctions and, what are known as adherens junctions, connecting cels to cells. Mesenchymal (stem) cells have an elongated shape, migrate easily, as well as the ability to invade surrounding tissues. This fundamental transition leads to the acquisition of stem cell properties, which renders the cells multipotent, i.e., capable of differentiating into various cell types.
When EMT was first discovered in the late 1960s it was revealed that EMT, along with its reverse process mesenchymal–epithelial transition (MET), are essential processes involved in embryonic development. This same process of EMT induction in CFCs produces CFC stem cells, which have invasive capabilities as well as all the other properties required for successful metastases. Furthermore, an intermediate epithelial/mesenchymal (E/M) hybrid state occurs before a cell becomes a mesenchymal cell and these E/M hybrid cells have high plasticity, rendering them capable of transitioning between different states of EMT depending on the combination of epithelial markers and mesenchymal markers which are activated. These cells, then have stem cell properties such as the ability to self-renew, hence giving rise to both mature epithelial cells and mesenchymal cells, and then to transform into CFC stem cells. Consequently, EMT has been found to be responsible for chemotherapy resistance, metastasis, and tumor relapse.
These stem cells are a small but critical cell population in tumors by being the only cell type capable of metastasis and recurrence. And, since these cells are not only resistant to chemotherapy and radiotherapy, both of these “treatment” modalities actually stimulate the entire process of EMT, resulting in even more CFC stem cells.
By suppressing EMT and promoting cellular differentiation, proteolytic enzymes can reprogram CFCs into a non-malignant cell, thereby reducing tumor aggressiveness and preventing it from growing back.
Clinical Evidence in People
1. Colorectal CFCs
Oral enzyme therapy significantly reduced both disease-related symptoms and adverse effects from chemotherapy and radiotherapy. In addition, there was a trend toward prolonged survival in people receiving oral enzymes alongside compared to those receiving conventional therapy alone. Adverse reactions to enzyme therapy were minimal, affecting only 3.4% (21 of 616) of patients, and were limited to mild to moderate gastrointestinal symptoms.
2.Multiple Myeloma
In Stage III patients, enzyme therapy increased median survival from 47 to 83 months—a 3-year gain. Benefits were linked to immune modulation and reduced inflammatory markers.
3. Mucinous Peritoneal Tumors
A combination of Bromelain and NAC injected into tumors or peritoneum dissolved mucin deposits and improved surgical outcomes. Although long-term outcomes were not intended to measure, remarkable extension in survival was observed in people undergoing enzyme treatment.
4. Pancreatic CFCs
A pilot study of inoperable pancreatic CFCs with a comprehensive nutritional-enzyme protocol resulted in:
- One-year survival rate: 81%, two-year survival: 45%, and three-year survival: 36%, significantly exceeding outcomes typically seen in standard chemotherapy (Gemcitabine) treatment where median survival was 5.7 months, with only 18% surviving one year and 0% beyond 19 months.
- The protocol also included a diet emphasizing uncooked plant-based foods to preserve natural enzymes in the food, not only to assist in their digestion and enhance nutrient absorption but to preserve the body’s own pancreatic enzymes for systemic therapeutic effects. There is evidence that pancreatic enzymes not used for digestion are reabsorbed and returned to pancreas for further use, called enteropancreatic circulation. These enzymes, once in the bloodstream, could also have anti-tumor activity therefore contributing to the oral enzyme therapy.
In conclusion, proteolytic enzymes offer a multi-targeted approach to resolving CFCs. Their ability to reduce symptoms, support immune function, break down tumor barriers and target CFC (cancer) stem cells makes them an invaluable component of a truly effective integrative approach to the restoration of health from this condition.
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