D-Limonene Abstracts 1


D-limonene rich volatile oil from blood oranges inhibits angiogenesis, metastasis and cell death in human colon cancer cells

         (Chidambara Murthy, Jayaprakasha et al. 2012) Download

AIMS: To identify the chemical constituents of volatile oil from blood orange (Citrus sinensis (L) Osbeck) and understand the possible mechanisms of inhibition of colon cancer cell proliferation. MAIN METHODS: Volatile oil was obtained from blood oranges by hydro-distillation. Nineteen compounds were identified by GC-MS and d-limonene was found to be the major component. The blood orange volatile oil was formulated into an emulsion (BVOE) and examined for its effects on viability of colon cancer cells. In addition, experiments were performed to understand the possible mechanism of proliferation inhibition, angiogenesis and metasasis by BVOE. KEY FINDINGS: BVOE exhibited dose-dependent inhibition of cell proliferation and induced apoptosis in the colon cancer cells, as confirmed by flow cytometry. Immunoblotting of colon cancer cells treated with BVOE shows dose-dependent induction of Bax/Bcl2) and inhibition of vascular endothelial growth factor (VEGF). Furthermore, treatment of serum starved SW480 and HT-29 cells with 100mug/ml BVOE suggested the inhibition of VEGF and markers associated with inhibition of angiogenesis. The antiangiogenic activity of BVOE was also confirmed by inhibition of in vitro tube formation in human umbilical vein endothelial cells. Dose-dependent anti-metastasis activity and blockage of vascular endothelial growth factor receptor 1 (VEGFR1) binding following treatment with BVOE were confirmed by cell migration assays and immunoblots to detect decreased expression of matrix metalloproteinases (MMP-9). SIGNIFICANCE: The results of this study provide persuasive evidence of the apoptotic and anti-angiogenesis potential of BVOE in colon cancer cells. The extent of induction of apoptosis and inhibition of angiogenesis suggest that BVOE may offer great potential for prevention of cancer and may be appropriate for further studies.

Ras pathway activation in gliomas: a strategic target for intranasal administration of perillyl alcohol

         (da Fonseca, Linden et al. 2008) Download

INTRODUCTION: Targeted therapy directed at specific molecular alterations is already creating a shift in the treatment of cancer patients. Malignant gliomas commonly overexpress the oncogenes EGFR and PDGFR and contain mutations and deletions of the tumor suppressor genes PTEN and TP53. Some of these alterations lead to activation of the P13K/Akt and Ras/MAPK pathways, which provide targets for therapy. Perillyl alcohol (POH), the isoprenoid of greatest clinical interest, was initially considered to inhibit farnesyl protein transferase. Follow-up studies revealed that POH suppresses the synthesis of small G proteins, including Ras. Intranasal delivery allows drugs that do not cross the blood-brain barrier to enter the central nervous system. Moreover, it eliminates the need for systemic delivery, thereby reducing unwanted systemic side effects. MATERIALS AND METHODS: Applying this method, a phase I/II clinical trial of POH was performed in patients with relapsed malignant gliomas after standard treatment: surgery, radiotherapy, and chemotherapy. POH was administrated in a concentration of 0.3% volume/volume (55 mg) four times daily in an interrupted administration schedule. The objective was to evaluate toxicity and progression-free survival (PFS) after six months of treatment. The cohort consisted of 37 patients, including 29 with glioblastoma multiforme (GBM), 5 with grade III astrocytoma (AA), and 3 with anaplastic oligodendroglioma (AO). Neurological examination and suitable image analysis (computed tomography (CT), magnetic resonance imaging (MRI)) established disease progression. Complete response was defined as neurological stability or improvement of conditions, disappearance of CT/MRI tumor image, and corticosteroid withdraw; partial response (PR) as > or =50 reduction of CT/MRI tumor image, neurological stability, or improvement of conditions and corticosteroid requirement; progressive course (PC) as > or =25 increase in CT/MRI tumor image or the appearance of a new lesion; and stable disease as a lack of any changes in the CT/MR tumor image or neurological status. RESULTS: After six months of treatment, PR was observed in 3.4% (n=1) of the patients with GBM and 33.3% (n=1) with AO; stable disease in 44.8% (n=13) with GBM, 60% (n=3) with AA, and 33.3% (n=1) with AO; and PC in 51.7% (n=15) with GBM, 40% (n=2), with AA and 33.3% (n=1) AO. PFS (sum of PRs and stable disease) was 48.2% for GBM, 60% for AA, and 66.6% for AO patients. CONCLUSIONS: The preliminary results indicate that intranasal administration of the signal transduction inhibitor POH is a safe, noninvasive, and low-cost method. There were no toxicity events and the regression of tumor size in some patients is suggestive of antitumor activity.

Citrus peel use is associated with reduced risk of squamous cell carcinoma of the skin

         (Hakim, Harris et al. 2000) Download

Limonene has demonstrated efficacy in preclinical models of breast and colon cancers. The principal sources of d-limonene are the oils of orange, grapefruit, and lemon. The present case-control study was designed to determine the usual citrus consumption patterns of an older Southwestern population and to then evaluate how this citrus consumption varied with history of squamous cell carcinoma (SCC) of the skin. In this Arizona population, 64.3% and 74.5% of the respondents reported weekly consumption of citrus fruits and citrus juices, respectively. Orange juice (78.5%), orange (74.3%), and grapefruit (65.3%) were the predominant varieties of citrus consumed. Peel consumption was not uncommon, with 34.7% of all subjects reporting citrus peel use. We found no association between the overall consumption of citrus fruits [odds ratio (OR) = 0.99, 95% confidence interval (CI) = 0.73-1.32] or citrus juices (OR = 0.97, 95% CI = 0.71-1.31) and skin SCC. However, the most striking feature was the protection purported by citrus peel consumption (OR = 0.66, 95% CI = 0.45-0.95). Moreover, there was a dose-response relationship between higher citrus peel in the diet and degree of risk lowering. This is the first study to explore the relationship between citrus peel consumption and human cancers. Our results show that peel consumption, the major source of dietary d-limonene, is not uncommon and may have a potential protective effect in relation to skin SCC. Further studies with large sample sizes are needed to more completely evaluate the interrelationships between peel intake, bioavailability of d-limonene, and other lifestyle factors.

Phase II trial of perillyl alcohol (NSC 641066) administered daily in patients with metastatic androgen independent prostate cancer

         (Liu, Oettel et al. 2003) Download

OBJECTIVE: We conducted a phase II multicenter trial of perillyl alcohol in patients with advanced hormone refractory prostate cancer (HRPC). The primary endpoint was to evaluate the 6-month progression-free survival given the potential cytostatic nature of the drug. Secondary objectives included assessing acute and chronic toxicities, as well as measuring objective response rates. METHODS: Patients with metastatic androgen-independent prostate cancer that failed at least one prior chemotherapeutic or experimental regimen were eligible. Perillyl alcohol was administered orally at 1200 mg/m2/dose four times daily and continued until disease progression or development of unacceptable toxicity. RESULTS: Fifteen patients were eligible. Six patients received less than one cycle (4 weeks) of drug, four of which stopped because of drug intolerance. Only six patients received more than two cycles of therapy and were considered evaluable for response. Main toxicity included grade 1-2 gastrointestinal intolerance (nausea/vomiting in 60% of the patients) and fatigue (47%). One patient developed a grade 4 hypokalemia that was felt likely attributable to the drug. No objective responses were seen. All patients either progressed or withdrew from the study secondary to drug intolerance before the 6-month time period. CONCLUSION: Perillyl alcohol administered at this dose and formulation did not have any objective clinical activity in this patient population.

Inhibition of growth and metastasis of human gastric cancer implanted in nude mice by d-limonene

         (Lu, Zhan et al. 2004) Download

AIM: To investigate the effects and mechanism of d-limonene on the growth and metastasis of gastric cancer in vivo. METHODS: Metastatic model simulating human gastric cancer was established by orthotopic implantation of histologically intact human tumor tissue into gastric wall of nude mice. One percent d-limonene was orally administered at dose of 15 ml/kg every other day for seven weeks. Eight weeks after implantation, tumor weight, inhibition rate, apoptotic index (AI), microvessel density (MVD), vascular endothelial growth factor (VEGF), variation of ultrastructure, and the presence of metastasis were evaluated, respectively, after the mice were sacrificed. RESULTS: The tumor weight was significantly reduced in 5-FU group (2.55+/-0.28 g), d-limonene group (1.49+/-0.09 g) and combined treatment group (1.48+/-0.21 g) compared with the control group(2.73+/-0.23 g, P<0.05). In 5-FU group, d-limonene group, combined treatment group, the inhibition rates were 2.60%,47.58% and 46.84% and 0, respectively; AI was (3.31+/-0.33)%, (8.26+/-1.21)%, (20.99+/-1.84)% and (19.34+/-2.19)%, respectively; MVD was (8.64+/-2.81), (16.77+/-1.39), (5.32+/-4.26) and (5.86+/-2.27), respectively; VEGF expression was (45.77+/-4.79), (41.34+/-5.41), (29.71+/-8.92) and (28.24+/-8.55), respectively. The incidences of peritoneal metastasis also decreased significantly in 5-FU group(77.8%), d-limonene group (20.0%) and combined group (22.2%) compared with control group (100%) versus 62.5%,30% and 22.2%) (P<0.05). Liver metastasis was also inhibited and the incidences decreased significantly in 5-FU group, d-limonene group and combined group than that in control group (87.5% vs 55.5%, 20.0% and 22.2% respectively)(P<0.05). The incidence of ascites in control group, 5-FU group, d-limonene group and combined group was 25.0%, 22.2%, 0, 0, respectively and 12.5%, 11.1% 0, 0, with respect to the metastasis rate to other organs. CONCLUSION: d-limonene has antiangiogenic and proapoptotic effects on gastric cancer, thereby inhibits tumor growth and metastasis. Combination of d-limonene with cytotoxic agents may be more effective.

Phase I and pharmacokinetic study of D-limonene in patients with advanced cancer. Cancer Research Campaign Phase I/II Clinical Trials Committee

         (Vigushin, Poon et al. 1998) Download

PURPOSE: D-Limonene is a natural monoterpene with pronounced chemotherapeutic activity and minimal toxicity in preclinical studies. A phase I clinical trial to assess toxicity, the maximum tolerated dose (MTD) and pharmacokinetics in patients with advanced cancer was followed by a limited phase II evaluation in breast cancer. METHODS: A group of 32 patients with refractory solid tumors completed 99 courses of D-limonene 0.5 to 12 g/m2 per day administered orally in 21-day cycles. Pharmacokinetics were analyzed by liquid chromatography-mass spectrometry. Ten additional breast cancer patients received 15 cycles of D-limonene at 8 g/m2 per day. Intratumoral monoterpene levels were measured in two patients. RESULTS: The MTD was 8 g/m2 per day; nausea, vomiting and diarrhea were dose limiting. One partial response in a breast cancer patient on 8 g/m2 per day was maintained for 11 months; three patients with colorectal carcinoma had prolonged stable disease. There were no responses in the phase II study. Peak plasma concentration (Cmax) for D-limonene ranged from 10.8+/-6.7 to 20.5+/-11.2 microM. Predominant circulating metabolites were perillic acid (Cmax 20.7+/-13.2 to 71+/-29.3 microM), dihydroperillic acid (Cmax 16.6+/-7.9 to 28.1+/-3.1 microM), limonene-1,2-diol (Cmax 10.1+/-8 to 20.7+/-8.6 microM), uroterpenol (Cmax 14.3+/-1.5 to 45.1+/-1.8 microM), and an isomer of perillic acid. Both isomers of perillic acid, and cis and trans isomers of dihydroperillic acid were in urine hydrolysates. Intratumoral levels of D-limonene and uroterpenol exceeded the corresponding plasma levels. Other metabolites were trace constituents in tissue. CONCLUSIONS: D-Limonene is well tolerated in cancer patients at doses which may have clinical activity. The favorable toxicity profile supports further clinical evaluation.


Chidambara Murthy, K. N., G. K. Jayaprakasha, et al. (2012). "D-limonene rich volatile oil from blood oranges inhibits angiogenesis, metastasis and cell death in human colon cancer cells." Life Sci 91(11-12): 429-39. [PMID: 22935404]

da Fonseca, C. O., R. Linden, et al. (2008). "Ras pathway activation in gliomas: a strategic target for intranasal administration of perillyl alcohol." Arch Immunol Ther Exp (Warsz) 56(4): 267-76. [PMID: 18726148]

Hakim, I. A., R. B. Harris, et al. (2000). "Citrus peel use is associated with reduced risk of squamous cell carcinoma of the skin." Nutr Cancer 37(2): 161-8. [PMID: 11142088]

Liu, G., K. Oettel, et al. (2003). "Phase II trial of perillyl alcohol (NSC 641066) administered daily in patients with metastatic androgen independent prostate cancer." Invest New Drugs 21(3): 367-72. [PMID: 14578686]

Lu, X. G., L. B. Zhan, et al. (2004). "Inhibition of growth and metastasis of human gastric cancer implanted in nude mice by d-limonene." World J Gastroenterol 10(14): 2140-4. [PMID: 15237454]

Vigushin, D. M., G. K. Poon, et al. (1998). "Phase I and pharmacokinetic study of D-limonene in patients with advanced cancer. Cancer Research Campaign Phase I/II Clinical Trials Committee." Cancer Chemother Pharmacol 42(2): 111-7. [PMID: 9654110]