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Paw Paw and Cancer: From Discovery to Clinical

Trials

Jerry L. McLaughlin, B.S.(Pharm.), M.S., Ph.D, R.Ph.

Emeritus Professor of Pharmacognosy

Purdue University

West Lafayette, IN

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Disclaimer

The following information is for educational purposes only and is not intended for the mitigation, cure, or treatment of medical conditions.

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Typical Cancer Treatments•Chemotherapy- anti-metabolites, alkylating agents, tubulin inhibitors, topoisomerase inhibitors, misc. (adriamycin, etc.)

•Radiation- Free radical oxidization of cell components

•Surgery- Tumor/lymphectomy/mastectomy

•Chemo side effects: hair loss, GI bleeding, bone marrow depression, infection and induction of new cancers

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Summary of Plant Anticancer Work:

(Purdue U., 1971-99)

•Developed brine shrimp and potato disc assays (followed by cell culture)

•Supported by NCI for 20 years

•Obtained and screened over 3500 species of higher plants.

•Activity directed fractionation isolated over 350 new cytotoxic compounds*

•Annonaceous acetogenins were the most potent leads

*see McLaughlin and Chang, Recent Advances in Phytochemistry, 33, 89-132, 1999

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•These are the fruits of the North American Paw paw tree

•In the midwest this is called the Indiana Banana

•The ripe fruits taste like banana custard

•The scientific name is Asimina triloba

•A fluid extract of the seeds was sold as an emetic by Eli Lilly in 1898

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Annonaceae•120 genera

•2100 species

•mainly tropical and subtropical

•mostly small trees and shrubs

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This is guanabana or Annona muriata (the competition)

It is also called graviola or Brazilian paw paw

•Brand X graviola capsules 24x less potent than paw paw extracts

•Brand Y graviola capsules 56x less potent than paw paw extracts

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Annonaceous acetogenins•Rapidly growing class of natural products, with potent in vivo antitumor, cytotoxic and pesticidal activities.

•Only found in several genera of the Annonaceae family.

•Over 400 isolated since 1982. (Jolad et al., J. Org. Chem., 47, 3151-3153, 1982)

•C-35/C-37 fatty acid derivatives + terminal methylated , -unsaturated -lactone or -keto-lactone ring + 0-3 tetrahydrofuran rings.

34 242

1

36

37

4o

O

o

OHOH

o

OH

(Hui, et al., Tetrahedron, 45, 6941-6948, 1989)

Bullatalicin

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Bullatacin (from Annona bullata)

(Hiu et al., Journal of Natural Products, 52, 463-477, 1989)

Major Functional Groups of the Annonaceous Acetogenins

O o

oO

O

65

4

2

1

35(33) 37(35)

36(34)

3

o

O

65

43

2 1

36(34)

35 (33)37(35)

34 24

S23 R

21

36

37

R4

15

16o

O

o

OH

OH

o

OH

35(33) 36(34)

37(35)

o

O

HO

65

4

3

2 1

o

OH OH

o

OH

oo

OH OH OH

ooo

OH

OH OAC OH

OH

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Compounds A B C D E

Trilobacin (1) threo trans erythro cis threo

Asimicin (2) threo trans threo trans threo

Bullatacin (3) threo trans threo trans erythro

Bullatacinone (4) threo trans threo trans erythro

o

OH

(CH2)8 R124

23 20 19 1615

534E

C

o

OH

CH3(CH2)8

B

A

D

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1

2

43 35 37

1,2,3 R1=R

o

OOH

4 R1= R

35

o

O

O

4

2

1

37

36

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Stereochemical Aspects of the Major Paw Paw Acetogenins

Rieser et al., Journal of the American Chemical Society 114, 10203-10213, 1992

Gu et al.,Journal of Organic Chemistry, 59, 5162-5172, 1994

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•Over 50 acetogenin peaks in paw paw•Isolated one-by-one•Structurally characterized

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Brine Shrimp Lethality Assay (BST)

•Artemia salina Leach Sea Monkeys

•Rapid, in-house, and low cost substitute for cytotoxicity assays

•Correlates well with other in vivo and in vitro cytotoxicity assays

•Responsible for isolation of numerous, chemically and pharmacologically diverse, antitumor and pesticidal compounds

•Records lethal concentration needed to kill 50% of the shrimp (LC50 value with upper and lower 95% confidence levels)

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Plant Part Extracted LC50 in ppm % yield Twigs 0.042 (0.20-0.09) 1.78Unripe fruit 0.060 (0.03-0.08) 5.11Root wood 0.060 (0.03-0.08) 1.27Seed 0.065 (0.03-0.10) 4.03Stem bark (7-88 ) 0.077 (0.04-0.12) 2.71Stem bark (10-90) 0.102 (0.06-0.15) 1.96Stem bark (10-90) 0.104 (0.03-0.20) 2.52Root bark 0.135 (0.09-0.21) 2.72Stem, wood, & leaves 0.202 (0.14-0.31) 1.6Stem wood 4.86 (0.37-11.93) 0.9 Leaves 53.6 (33-82) 4.36

Brine Shrimp Lethality and % Yields from plant parts of Asimina

triloba

Conclusion: twigs are a renewable source of biomass

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Bioactivity of Asimina triloba Fractions against Pests

Fraction 1000 100 10 1 1 1

F017 100 90 0 0 0 100

F018 50 0 0 0 0 0

F019 100 100 70 0 100 100

F020 100 100 100 50 100 100

Blowfly larvae (%)

C. elegans (%)Mosquito larvae (ppm)

*The results are corrected for control deaths by Abbott’s formula

Testing conducted at Eli Lilly and Co. Greenfield, IN

(Alhofahi et al., Insecticides of Plant Origin, Amer. Chem. Soc., Washington, D.C., 1989, pp.(25-43)

% Mortality*

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•This lice remover shampoo was introduced in Sept. 2001.

•Last year we commissioned studies proving that it removes fleas and ticks as well as lice

•100% effective in clinical trials

•Effective against pesticide-resistant pests

McCage et al., Phytomedicine,9, 743-748, 2002

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•Most potent part

•Easiest to collect

•Allows the tree to survive

•This batch was worthless because it lacked potency

•Time of collection must be important

University of Maryland paw paw plantation

Why use the twigs?

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When Should Paw Paw Twigs Be Collected?

•Harvest only in peak month according to:–HPLC

–Brine shrimp test

Gu et al; Phytochemical Analysis, 10, 32-38, 1999

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Biological Activities of Maryland (WMREC) Paw Paw Plantation

135 individual Asimina triloba twig samples collected 26 Sept. 1995 Grand BST Mean= 1.2ppm SE=0.30ppm

High Producers Low Producers

Tree Sample BST-LC50(ppm) Tree Sample BST-LC50(ppm)

4-11 0.033+/-0.0010 2-32 32 +/- 12

5-82 0.053+/-0.015 1-19 12+/- 4.7

4-70 0.056+/-0.0354 4-46 10 +/- 0.55

2-88 0.063+/-0.020 5-14 8.4 +/- 2.5

Individual paw paw trees can vary 1000x in twig potency; thus, bioassay of materials is essential.

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Two sites of cellular action: (depletes ATP)

Lewis et al., Pesticide Biochemistry and Physiology, 45, 12-23, 1993.

Ahammadsahib et al., Life Sciences, 53, 1113-1120, 1993.

Hollingworth et al., Biochemical Society Transactions, 22, 230-233, 1994.

Schuler et al., Proceedings of the National Academy of Sciences USA, 96, 4149-4155, 1999.

Morre et al., Life Sciences, 56, 343-348, 1995.

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Depletes the DNA and RNA Building Blocks Necessary for New, Abnormal Cell Division

Building blocks of RNA and DNA are lowered in just 3 days.

S. Fotopoulos et al., Clinical Reference Labs (unpublished)

Inhibition of DNA and RNA probably accounts for antiviral effects (cold sores, shingles, etc.) seen with these products

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Oberlies et al., Cancer Letters, 115, 173-179, 1997

Oberlies et al., Journal of Medicinal Chemistry, 40, 2102-2106, 1997

Johnson et al., in Biologically Active Natural Products, CRC Press, Boca Raton, 1999, pp.173-183

Diagram of the P-170 glycoprotein multidrug resistant pump

23J. McAlpine, Abbott Laboratories (unpublished data)

24Oberlies et al., Cancer Letters, 96,55-62, 1995

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In vivo anticancer activities of two paw paw acetogenins against mice bearing L1210 murine

leukemia

Product

Survival 1st run (% T/C)

Weight change (g/mouse)

Survival 2nd run (% T/C)

Bullatacin 50.0 138 138 -0.4

Bullatacinone400 144 1.1

Taxol 15000 139 -2.5

Dose* (g/kg)

Conclusion: 300 times as potent as taxol in vivo

Acetogenins cause much less weight loss than taxol

Studies performed at the Upjohn Co.

Ahammadsahib et al., Life Sciences, 53, 1113-1120, 1993

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Anti-tumor efficacy of Paw Paw compounds against A2780 human ovarian carcinoma implanted in athymic mice

Product Dose (mg/kg) TGI(%) Wt. Change g/mouse

Bullatacin 0.10 68 -1.5

0.05 67 -0.3

0.025 35 0.1

Bullatacinone 0.50 33 -0.7

0.25 24 0.1

0.125 52 -0.1

Bullatalicin 2.00 63 -0.9 1.00 75 -0.1 0.50 42 -0.2

Cisplatin 5.00 78 -1.1

V.Control -0.3TGI%= tumor groth inhibition %; animals were tested (ip) daily for 10 days starting day one after tumor implantation. Studies performed by the Upjohn Company. Ahammadsahib et al., Life Sciences, 53, 1113-1120, 1993

Conclusion: Acetogenins approach the effectiveness of cisplatin with less weight loss

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DNA laddering proves apoptosis

Geahlen, Purdue University(unpublished data)

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Over 100 Scientific papers on the chemistry and biology of the paw paw compounds

This work was honored on the cover of J. Nat. Prod. For the first 6 months of 1999. The zebra swallowtail butterfly concentrates the acetogenins as a protection from predation by birds

Martin et al., Journal of Natural Products, 62, 2-4, 1999

Alali et al., Journal of Natural Products, 62, 504-540, 1999 (our 5th comprehensive review)

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4 Mechanisms by Which Paw Paw Regulates Cells

1. Slows or stops ATP (adenosine triphosphate) production, thus energy is depleted. Apoptosis results in programmed cell death

a. At NADH: ubiquinone oxidoreductase (mitochondrial)

b. At NADH: oxidase (tumor cell membranes)

2. ATP is a direct and indirect precursor of DNA and RNA, thus cell reproduction is slowed or stopped; this effect blocks viral replication (cold sores, shingles, etc.)

3. Angiogenesis in endothelial cells requires ATP, thus , blood vessel formation is slowed or stopped

4. The multiple-drug resistance (MDR) pump requires ATP, thus drug resistant cells are slowed or stopped . In doing so it helps restore the function of refractive chemotherapy.

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Paw Paw is Non-Toxic

• Beagle safety study• Impossible to overdose• 32 capsules four times a day were non-

toxic due to vomiting.• Conclusion: Paw Paw is more effective

than common drugs and exhibits no toxicity.

____________________________D’Ver, White Eagle Labs, (unpublished results)

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Clinical Results: Breast Cancer

Patient #3 - Tumor size reduced and was not detected with MRI.

Patient #8 – 7 months Chemo + paw paw: Tumor almost completely disappeared. Biopsy after radical mastectomy showed no tumors in 14 lymph nodes—patient is cancer free

Patient #12 Stage IV 6 weeks of paw paw: 50% reduction in tumor markers (16080), size of tumors reduced significantly

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Clinical Results: Prostate Cancer

Patient #48 – Over 6 months PSA went from 36 33 30

Patient #53 – reduced pressure on prostate, reduced frequency of urination

Patient #56- Stage IV: distinct reduction in tumor masses (25% reduction verified by CT scan) after only 6 weeks

Patient #75 PSA of 4.5 1.7 after 6-8 weeks.

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Clinical Results: Lymphoma-Non Hodgkins

•Patient # 52

•Aug 2002 start date

•Patient has had lymphoma for 6 1/2 years with 3 rounds of chemotherapy

•34.1 white cell count was rising but reduced to 11.2 (after 35 days w/paw paw)(3.5-12.0 is the normal range for white cells counts)

•67.2% lymphocytes 30% (after 35 days w/ paw paw)(lymphocytes should normally be 16-43%)

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Clinical Results: Stage IV lung cancer

•Patient #51 In two months of paw paw tumor markers have improved

•CEA went from 275 to 222.

•Weight gain of 5 lbs.; no side effects

•Ambulatory after having previously been bed ridden/wheelchair and can now walk.

•Previous treatment:2 years of chemo for refractory lung cancer (chemotherapy resistant)

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Clinical Results: Stage IV

Melanoma (lung metastases)

Patient #52

In just 4 days on paw paw patient could breathe without “burning” sensation in his lungs

Strength returned and now can ride a bike, walk

Two lipomas on arm have decreased in size

Toe-nail fungus (had for 10 years) is going away

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Summary of Clinical Trials With Paw Paw Cell-Reg

•100+ Patients over the past year

•Many types of tumors represented

•Significant reductions seen in tumor sizes (verified by CT, etc.)

•Significant reductions in tumor antigen levels (PSA, CA2729, CA125, alkaline phosphatase, etc.)

•Very few side effects; mostly none; nausea and vomiting (2 people); itching (1 person); many reported “increased energy”.

•No hair loss, no bone marrow depression, No GI bleeding

•DON’T GIVE with COQ10 or thyroid stimulators or antioxidants

•Benefits seen with cold sores, shingles, toe nail fungus, acne, athletes foot, eczema & psoriasis (in capsules, lotion or salve).