Traditionally used for
- Urinary & fluids
- Skin
Cautions & contraindications
- Pregnancy
- Bleeding disorders
- Toxic — professional use only
☯ TCM Properties
Disperses Stagnant Blood, d isperses accumulation and inhibits carcinoma
Traditional Chinese Uses
Xi Shu is the fruit, bark and root of Camptotheca acuminata (the "happy tree"), a comparatively modern addition to the materia medica. Bitter and cold, it disperses Blood stasis, breaks up accumulations and masses, clears Heat and resolves toxicity. It is used mainly as an anti-tumor and Heat-clearing agent for various masses and carcinomas, and has been applied to conditions such as gastric, intestinal, bladder and skin tumors, chronic leukemia, and psoriasis.
The tree is the natural source of camptothecin, from which the chemotherapy drugs topotecan and irinotecan (topoisomerase-I inhibitors) are derived. Because the active constituents are cytotoxic, crude Xi Shu is toxic — it can cause bone-marrow suppression, severe gastrointestinal reactions and bleeding — and is not for self-administration; it is contraindicated in pregnancy. It is used only within professional oncologic settings.
Western Herbalism Properties
Relationships
Full-screen graph →Click a node for details · double-click to expand it · Ctrl/⌘ + scroll or two fingers to zoom and pan.
Botanical Description
Camptotheca acuminata Decne. (Nyssaceae), the happy tree or cancer tree, is a fast-growing deciduous broadleaved tree reaching 20-25 m in height, endemic to southern China and Tibet. The trunk is straight with smooth grey bark; young branches are reddish-green and glabrous. Leaves are opposite, ovate to elliptic-oblong, 12-28 cm long, with entire margins, an abruptly acuminate tip, and prominent pinnate venation, glossy dark green above and lighter beneath with pubescent veins. The inflorescence is a globular head 1.5-2 cm in diameter consisting of many small greenish-white flowers, the heads arranged in axillary or terminal clusters, with separate male, female, and bisexual heads on the same tree. The fruit is a narrow winged samara 2-2.5 cm long, brown at maturity, aggregated into pendulous heads. The tree is the original natural source of camptothecin and its derivatives (irinotecan, topotecan), used in TCM and modern oncology for cancer treatment.
Active Constituents
Camptothecin
Monoterpene indole (pyrrolo[3,4-b]quinoline) alkaloidConcentration: roughly 0.4% of the dry weight of young leaves, about 1.5 times the level in seed and 2.5 times the level in bark; falls rapidly as leaves mature
Camptothecin is a topoisomerase I poison: it traps the covalent topoisomerase I-DNA cleavage complex so that advancing replication forks convert reversible single-strand nicks into lethal double-strand breaks. Activity requires the intact 20(S)-lactone E-ring, which hydrolyses to the far less active open carboxylate at physiological pH — the instability that defeated the parent alkaloid in the clinic and drove the development of the semisynthetic derivatives irinotecan and topotecan.
10-Hydroxycamptothecin
Monoterpene indole alkaloidConcentration: a minor congener of camptothecin; with 10-methoxycamptothecin it accounts for up to about half of total camptothecin-type alkaloid in young bark and up to about 30% in mature leaves, and is more than twice as abundant as the 10-methoxy compound in young bark
A C10-hydroxylated camptothecin that also poisons topoisomerase I. It is manufactured in China as a purified parenteral oncology drug (hydroxycamptothecin injection, HCPT) under specialist supervision; that licensed injectable is a different thing from the crude plant, and nothing in the herbal drug delivers a controlled dose of it.
10-Methoxycamptothecin
Monoterpene indole alkaloidConcentration: the dominant camptothecin derivative of leaf tissue, where it is more than ten-fold more abundant than 10-hydroxycamptothecin; the ratio is reversed in young bark
Formed by O-methylation of 10-hydroxycamptothecin. It contributes to the total topoisomerase I-inhibiting alkaloid burden of any crude extract, and its very different leaf-versus-bark ratio is one reason the toxicity of a crude preparation cannot be predicted from the plant part alone.
Hyperoside
Flavonol glycoside (quercetin 3-O-galactoside)Concentration: co-extracted with the camptothecin alkaloids from the seed
A non-cytotoxic flavonol glycoside recovered alongside the camptothecin alkaloids from Camptotheca acuminata seed. It is of interest mainly because it must be separated from the alkaloids during manufacture, not because it contributes to the antitumour activity.
⚠ Drug Interactions
Irinotecan and topotecan (licensed camptothecin derivatives)
Irinotecan and topotecan are semisynthetic derivatives of camptothecin, the alkaloid of Camptotheca acuminata, and share its target. Crude Xi Shu bark or fruit contains camptothecin, 10-hydroxycamptothecin and 10-methoxycamptothecin in ratios that vary with plant part and season, so a decoction adds an unquantified extra dose of topoisomerase I poison to a drug that is already titrated to marrow tolerance. The clinical literature that established efficacy for this chemical class is entirely about the intravenous semisynthetic derivatives given under oncology supervision, never about a decoction of the tree, and the parent alkaloid itself failed in the clinic on toxicity grounds.
Clinical note: Xi Shu is not a herbal substitute for irinotecan or topotecan and must never be offered as one. Do not give the crude drug to a patient receiving either agent, and tell the oncology team if a patient has been taking it.
Myelosuppressive cytotoxic chemotherapy and radiotherapy
The dose-limiting toxicities recorded when purified camptothecin sodium was given intravenously in the NCI trials of 1970-1972 were unpredictable neutropenia and thrombocytopenia, gastrointestinal toxicity with significant diarrhoea, and haemorrhagic cystitis; these are on-target effects of topoisomerase I inhibition plus urinary excretion of the alkaloid, and clinical development of the parent compound was stopped because of them. Any preparation of the crude drug carries the same alkaloids, so it stacks marrow and mucosal toxicity onto concurrent chemotherapy or radiotherapy.
Clinical note: Treat Xi Shu as a cytotoxic, not as a supportive herb. Do not combine it with chemotherapy or radiotherapy; if a patient has taken it, check a full blood count and look for haematuria and diarrhoea.
Warfarin, direct oral anticoagulants and antiplatelet drugs
There are no interaction studies of the crude drug with anticoagulants. The concern is pharmacodynamic rather than pharmacokinetic: camptothecin caused thrombocytopenia and haemorrhagic cystitis in the historical intravenous trials, and either would be far more dangerous in a patient who is anticoagulated or on antiplatelet therapy.
Clinical note: Avoid the combination. Any haematuria in a patient taking both should be treated as an emergency rather than attributed to the anticoagulant alone.
Evidence Tier
Moderate evidence · 3 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
3
0 verified · 3 unverified
Show 3 studies
- Preliminary pharmacologic and clinical evaluation of camptothecin sodium (NSC-100880)
- Phase I clinical trial of weekly and daily treatment with camptothecin (NSC-100880): correlation with preclinical studies
- Phase II study of camptothecin (NSC-100880) in the treatment of advanced gastrointestinal cancer
In vitro / animal
0
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Preliminary pharmacologic and clinical evaluation of camptothecin sodium (NSC-100880)
The first NCI clinical evaluation of camptothecin, given as the water-soluble sodium salt by intravenous injection to cancer patients — a purified single alkaloid administered parenterally, not a decoction or extract of Camptotheca acuminata bark or fruit. It reported some antitumour signal, chiefly in gastrointestinal tumours, alongside the toxicity pattern that later reviews of the programme summarise as unpredictable neutropenia and thrombocytopenia, gastrointestinal toxicity with significant diarrhoea, and haemorrhagic cystitis. This study says nothing about the safety or efficacy of the crude herb taken by mouth.
Phase I clinical trial of weekly and daily treatment with camptothecin (NSC-100880): correlation with preclinical studies
A parallel NCI Phase I dose-finding study of intravenous camptothecin sodium on weekly and daily schedules — again the isolated alkaloid as a sterile injection under hospital supervision, not the herbal drug. Together with the Gottlieb series it defined the dose-limiting myelosuppression and the haemorrhagic cystitis that stopped development of the parent compound and redirected the field towards the semisynthetic derivatives irinotecan and topotecan. Nothing here supports oral use of Xi Shu.
Phase II study of camptothecin (NSC-100880) in the treatment of advanced gastrointestinal cancer
The Phase II test of intravenous camptothecin sodium in advanced gastrointestinal malignancy. It is the trial cited in later reviews of the camptothecin programme as showing the agent to be ineffective and highly toxic at tolerated doses, and, with the companion melanoma study, the reason clinical testing of the parent alkaloid ceased. The agent studied was a purified intravenous drug; the failure of that drug is a reason to be more cautious with the crude plant, not less.
References
- O'Leary J, Muggia FM. Camptothecins: a review of their development and schedules of administration . European Journal of Cancer (1998) [DOI]
- Hartmann JT, Lipp HP. Camptothecin and Podophyllotoxin Derivatives . Drug Safety (2006) [DOI]
- López-Meyer M, Nessler CL, McKnight TD. Sites of Accumulation of the Antitumor Alkaloid Camptothecin inCamptotheca acuminata . Planta Medica (1994) [DOI]
- Salim V, Jones AD, DellaPenna D. Camptotheca acuminata 10-hydroxycamptothecin O-methyltransferase: an alkaloid biosynthetic enzyme co-opted from flavonoid metabolism . The Plant Journal (2018) [DOI]
- Zhang J, Yu Y, Liu D, Liu Z. Extraction and composition of three naturally occurring anti-cancer alkaloids in Camptotheca acuminata seed and leaf extracts . Phytomedicine (2007) [DOI]
- Wall ME, Wani MC. Camptothecin and taxol: discovery to clinic--thirteenth Bruce F. Cain Memorial Award Lecture . Cancer Research (1995)
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
📝 Notes
Public notes from the community and your own private notes on Xi Shu.
No notes yet.