Papaya Leaf Shows Anti-Proliferative Effect on Prostate Cancer Cells

DOI: 10.1111/bju.13198
Conference: Prostate Cancer World Congress-August, 2015, At Cairns Convention Centre, Australia

“This study has shown that anti-Proliferative responses to papaya [leaf juice] extracts.”

Carica papaya leaf juice extracts have selective anti-proliferative responses in prostatic disease

This blog sponsored by the Julia Ruffin Project: researching, promoting, and growing papaya leaves for cancer


Papaya Leaf Slows Free Radical Destruction that Causes Aging and Cancer

We have published research articles that show the healing effect of papaya leaf on the liver. But this study explains how this action also has anti-aging and anti-cancer effects:

From the International Journal of Pharmacy

“…In general up on entry of any foreign particle enters in to our body. Free radicals can be generated, which is based on the size of the foreign particle or physico chemical characteristics of that foreign particle (1). The free radicals are not inactivated; their chemical reactivity can damage all cellular macromolecules including proteins, carbohydrates, lipids and nucleic acids. Their destructive effect on protein may play a role in the causation of diseases, like cataracts. Free radical damage to DNA is also implicated in the causation of cancer and its effect on LDL cholesterol is very likely responsible for heart disease. Free radicals are also responsible for ageing (2).
Iron over load causes liver toxicity by producing hydroxyl radicals by promoting Fenton reaction(3). Free radicals also can be able to cause various
diseases like neurodegenerative diseases (4), cardio vascular diseases (5), cancer etc. So the work started because of these serious effects up on the free radical generation, expecting that Herbal medicines have been used able to generate antioxidants, which can be provide balance between free radical generation and anti-oxidant levels or those anti-oxidants prevents the liver damage and gastric ulceration caused by free radicals….
In present study the antioxidant activity of aqueous extract of leaf of Carica papaya was found. From the study it was also found to decrease lipid peroxidation and significant increase in catalase, glutathione and protein with the aqueous extract of leaf of Carica papaya in dose dependant manner. Literature regarding phytoconstituents shows that aqueous extract of leaf of Carica papaya contains Alkaloids Carpain, Pseudo carpain, and dehydro carpaine I & II, Choline, Caproside, Vitamin C & E. Since all these constituents are found in the leaf of this plant it is possible that these constituents may be implicated in antioxidant activity of the species. Therefore, it was concluded that the aqueous extract of the leaf of Carica papaya possess antioxidant principles and has free radical scavenging activity.
The result have shown that the aqueous extract of the leaf of Carica papaya possesses antioxidant properties, supported by the decrease in lipid peroxidation and increase in the reduced glutathione and catalase activity in in vivo method. The in vivo antioxidant activities have been supported by its free radical scavenging activities in in-vitro method. Such antioxidant activity of Carica papaya might be responsible for its importance in traditional medicine for the treatment of various disorders. The present study opens many new areas of research work. This work can be continued in the future to study and confirm liver protective activity in different experimental models and also to isolate, identify, characterize and standardize the active principle(s) that are responsible for this activity.”

Balakrishna V*, Srikanth G, Ajay kumar Sarabu, Thippani Maneshwar
Department of Pharmacology, Vaageswari College of Pharamacy, Karimnagar, Andhra Pradesh, India
International Journal of Pharmacy
Journal Homepage:

Flavonoids make Papaya Leaf Tea Safe

In 2011 Brazilian scientists wanted to show that the apparent positive effect of papaya leaf on cancers was not toxic to the body.

The study used standard methods for discovery on this subject, and in the final analysis the study showed that papaya leaf is non-toxic by these methods and also disclosed the most likely substance in the papaya leaf that is responsible: it is the flavonoid in the leaf called rutin.

“…The results of this study indicated that an aqueous solution of the ethanolic extract of leaves of C. papaya, under the experimental conditions used, has low toxicity and an antimutagenic effect; flavonoids, such as rutin, may be the substances involved in this action.”

Antimutagenic activity of Carica papaya L. assayed in vivo by micronucleus test
Kalil, I.C.1; Gibson, B.A.V.1; Ribeiro, C.A.1; Benincá, L.S.1; Brasil, G.A.1; Andrade, T.U.1; Batitucci, M.C.P.2; Endringer, D.C.1*
1 Curso de Farmácia, Universidade Vila Velha – UVV 2 Universidade Federal do Espírito Santo – UFES
Recebido 22/09/2011 / Aceito 17/11/2011

International Journal of Herbal Medicine Documents Cancer Inhibition of Papaya Leaf

From Research Collected at the Bhupal’s Noble Institutes of Pharmaceutical Sciences in India’s largest state:

Carica papaya Linn: An Overview

Vijay Yogiraj, Pradeep Kumar Goyal, Chetan Singh Chauhan, Anju
Goyal, Bhupendra Vyas

February, 2015

” 5. Medicinal and Pharmacological properties of various parts of Carica papaya plant

5.1 Leaves
Papaya leaf has a numberless of benefits. In some parts of Asia, the young leaves of the papaya are steamed and eaten like spinach.
a) Dengue fever- Commencing on studies of Dr. Sanath Hettige, who conducted the research on 70 dengue fever patients, said papaya leaf juice helps increase white blood cells and platelets, normalizes clotting, and repairs the liver.
b) Cancer cell growth inhibition- Recent research on papaya leaf tea extract has demonstrated cancer cell growth inhibition. It appears to boost the production of key signaling molecules called Th1-type cytokines, which help regulate the immune system.
c) Antimalarial and antiplasmodial activity- Papaya leaves are made into tea as a treatment for malaria. Antimalarial and antiplasmodial activity has been noted in some preparations of the plant, but the mechanism is not
understood and not scientifically proven
d) Facilitate digestion- The leaves of the papaya plants
contain chemical compounds of carpain, Substance which kills microorganisms that often interfere with the digestive function.
Additional Benefits of Papaya Leaves: As an acne medicine, Increase appetite, Ease menstrual pain, Meat tenderizer, Relieve nausea.”

Memorial Sloan Cancer Center Records that Papaya Leaf Has Anti- Tumor Effect

“Papaya leaves exhibit anti-tumor, immunomodulatory (1), and antioxidant(9) effects in vitro….

Mechanism of Action
Papaya leaf extract modulates the immune system by enhancing the production of Th1 type cytokines, such as interleukin (IL-12), interferon (IFN-gamma) and tumor necrosis factor (TNF-alpha). Fractions with molecular weight less of than 1000 are most active in inhibiting tumor cell growth.”

The record on the website cites the references below:
1. Otsuki N, Dang NH, Kumagai E, et al. Aqueous extract of Carica papaya leaves exhibits anti-tumor activity and immunomodulatory effects. J Ethnopharmacol. Feb 17 2010;127(3):760-767.
9. Okoko T, Ere D. Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract.Asian Pac J Trop Biomed.2012 Jun;2(6):449-53.”

Constituents Recorded in the papaya leaf:
Carpaine, malic acid, quinic acid, manghaslin and clitorin, minor quantities of various malic acid derivatives, nicotiflorin, and rutin.(6)
Phenolic compounds: Dimethoxycoumarin, protocatechuic acid, p-coumaric acid, caffeic acid, chlorogenic acid, kaempferol and quercetin. (8)”

Studies Linking Cancer Survival to Papain (The enzyme in Papaya Leaf)

Papain is an active enzyme found in the natural papaya leaf. Papain is typically combined with two other proteases in oral enzyme therapy. The clinical study referenced below shows a significant positive difference in the survival rate for patients taking papain.

Systemic Enzyme Therapy in Oncology Effect and Mode of Action
Jörg Leipner and Reinhard Saller

Drugs 2000 Apr; 59 (4): 769-780

“…In this retrospective parallel-group cohort analysis, 166 patients who had received papain/trypsin/chymotrypsin (2 tablets 3 times daily) for at least 6 months were assigned to the active treatment group. The aim of the study was to investigate any effect of enzyme therapy on survival. A statistically significant mean prolongation of survival of 36 months was seen in patients with Stage III multiple myeloma (n = 54) in the enzyme group compared with the control group (n = 36) [83 months versus 47 months].”

Additional cases were reviewed naming less suffering and more survival when oral enzyme therapy that included papain was used as a complement to chemotherapy and radiation.

The mechanism of action was concluded to be:
“…This may constitute one of the mechanisms of action of enzyme therapy: orally administered enzymes seem to induce the synthesis of antiproteinases which in turn inactivate proteinases such as cathepsines”

Anti-Tumor Components in Papaya Leaf

“The ability of phytochemicals to inhibit tumor formation both in vitro and in vivo is well documented.”

Ichikawa, H., Nakamura, Y., Kashiwada, Y., and Aggarwal, B.B. Anticancer drugs designed by mother nature: Ancient drugs but modern targets. Curr. Pharm. Des 13, 3400–3416 (2007)

“Many of these [phytochemical] compounds have anti-oxidant, anti-proliferative, and pro-apoptotic effects on a variety of cancers, including leukemia, prostate, breast, colon, brain, melanoma, and pancreatic. Moreover, cancer stem cells have been identified for each of these blood and solid tumors paving the way for future studies to evaluate the efficacy of phytochemicals against cancer stem cells. The benefit of many of these phytochemicals is that they are well tolerated and are found in many food products that can be added to one’s diet. Furthermore, phytochemicals could be taken on a long-term basis to either prevent primary tumor formation or tumor recurrence.”

-Targeting Cancer Stem Cells with Phytochemicals
Brian T. Kawasaki, Elaine M. Hurt, Tashan Mistree and William L. Farrar

Papaya leaves contain a blend of phytochemicals named the “Kit for Cancer”.

“In the leaves of Carica papaya, components previously reported to potentially have anti-tumor activity include: tocopherol, lycopene, flavonoid, and benzylisothiocyanate.”

According to researchers:
Noriko Otsukia, Nam H. Dangb, Emi Kumagaia, Akira Kondoc, Satoshi Iwataa, Chikao Morimotoa
Aqueous extract of Carica papaya leaves exhibits anti-tumor activity and immunomodulatory effects

Related Posts on the effect of Papaya Leaf on Tumors

This post is for NJ’s friend.
The Julia Ruffin Project promotes, researches, and grows papaya leaf tea.