Curcumin Abstracts 3 - Cancer


Effects of curcumin on stem-like cells in human esophageal squamous carcinoma cell lines.
            (Almanaa et al., 2012)  Download
BACKGROUND:  Many cancers contain cell subpopulations that display characteristics of stem cells. Because these cancer stem cells (CSCs) appear to provide resistance to chemo-radiation therapy, development of therapeutic agents that target CSCs is essential. Curcumin is a phytochemical agent that is currently used in clinical trials to test its effectiveness against cancer. However, the effect of curcumin on CSCs is not well established. The current study evaluated curcumin-induced cell death in six cancer cell lines derived from human esophageal squamous cell carcinomas. Moreover, these cell lines and the ones established from cells that survived curcumin treatments were characterized. METHODS:  Cell loss was assayed after TE-1, TE-8, KY-5, KY-10, YES-1, and YES-2 cells were exposed to 20-80 μM curcumin for 30 hrs. Cell lines surviving 40 or 60 μM curcumin were established from these six original lines. The stem cell markers aldehyde dehydrogenase-1A1 (ALDH1A1) and CD44 as well as NF-κB were used to compare CSC-like subpopulations within and among the original lines as well as the curcumin-surviving lines. YES-2 was tested for tumorsphere-forming capabilities. Finally, the surviving lines were treated with 40 and 60 μM curcumin to determine whether their sensitivity was different from the original lines. RESULTS:  The cell loss after curcumin treatment increased in a dose-dependent manner in all cell lines. The percentage of cells remaining after 60 μM curcumin treatment varied from 10.9% to 36.3% across the six lines. The cell lines were heterogeneous with respect to ALDH1A1, NF-κB and CD44 expression. KY-5 and YES-1 were the least sensitive and had the highest number of stem-like cells whereas TE-1 had the lowest. The curcumin-surviving lines showed a significant loss in the high staining ALDH1A1 and CD44 cell populations. Tumorspheres formed from YES-2 but were small and rare in the YES-2 surviving line. The curcumin-surviving lines showed a small but significant decrease in sensitivity to curcumin when compared with the original lines. CONCLUSION:  Our results suggest that curcumin not only eliminates cancer cells but also targets CSCs. Therefore, curcumin may be an effective compound for treating esophageal and possibly other cancers in which CSCs can cause tumor recurrence.


Clearance of cervical human papillomavirus infection by topical application of curcumin and curcumin containing polyherbal cream: a phase II randomized controlled study.
            (Basu et al., 2013) Download
Curcumin and curcumin containing polyherbal preparations have demonstrated anti-microbial and anti- viral properties in pre-clinical studies. Till date no therapeutic intervention has been proved to be effective and safe in clearing established cervical human papillomavirus (HPV) infection. The present study evaluated the efficacy of Basant polyherbal vaginal cream (containing extracts of curcumin, reetha, amla and aloe vera) and of curcumin vaginal capsules to eliminate HPV infection from cervix. Women were screened by Pap smear and HPV DNA test by PCR. HPV positive women without high grade cervical neoplasias (N=287) were randomized to four intervention arms to be treated with vaginal Basant cream, vaginal placebo cream, curcumin vaginal capsules and placebo vaginal capsules respectively. All subjects were instructed to use one application of the assigned formulation daily for 30 consecutive days except during menstruation and recalled within seven days of the last application for repeat HPV test, cytology and colposcopy. HPV clearance rate in Basant arm (87.7%) was significantly higher than the combined placebo arms (73.3%). Curcumin caused higher rate of clearance (81.3%) than placebo though the difference was not statistically significant. Vaginal irritation and itching, mostly mild to moderate, was significantly higher after Basant application. No serious adverse events were noted.

Phase IIa clinical trial of curcumin for the prevention of colorectal neoplasia.
            (Carroll et al., 2011) Download
Curcumin is derived from the spice tumeric and has antiinflammatory and antineoplastic effects in vitro and in animal models, including preventing aberrant crypt foci (ACF) and adenomas in murine models of colorectal carcinogenesis. Inhibiting the production of the procarcinogenic eicosanoids prostaglandin E₂ (PGE₂) and 5-hydroxyeicosatetraenoic acid (5-HETE) can suppress carcinogenesis in rodents. Curcumin reduces mucosal concentrations of PGE₂ (via inhibition of cyclooxygenases 1 and 2) and 5-HETE (via inhibition of 5-lipoxygenase) in rats. Although preclinical data support curcumin activity in many sites, the poor bioavailability reported for this agent supports its use in the colorectum. We assessed the effects of oral curcumin (2 g or 4 g per day for 30 days) on PGE₂ within ACF (primary endpoint), 5-HETE, ACF number, and proliferation in a nonrandomized, open-label clinical trial in 44 eligible smokers with eight or more ACF on screening colonoscopy. We assessed pre- and posttreatment concentrations of PGE₂ and 5-HETE by liquid chromatography tandem mass spectroscopy in ACF and normal-tissue biopsies; ACF number via rectal endoscopy; proliferation by Ki-67 immunohistochemistry; and curcumin concentrations by high-performance liquid chromatography in serum and rectal mucosal samples. Forty-one subjects completed the study. Neither dose of curcumin reduced PGE₂ or 5-HETE within ACF or normal mucosa or reduced Ki-67 in normal mucosa. A significant 40% reduction in ACF number occurred with the 4-g dose (P < 0.005), whereas ACF were not reduced in the 2-g group. The ACF reduction in the 4-g group was associated with a significant, five-fold increase in posttreatment plasma curcumin/conjugate levels (versus pretreatment; P = 0.009). Curcumin was well tolerated at both 2 g and 4 g. Our data suggest that curcumin can decrease ACF number, and this is potentially mediated by curcumin conjugates delivered systemically.

A novel curcumin-based vaginal cream Vacurin selectively eliminates apposed human cervical cancer cells.
            (Debata et al., 2013) Download
OBJECTIVE:  Human papillomavirus (HPV) infections remain a leading cause of mortality worldwide. In the U.S. strategies via screening and vaccination prevent HPV-associated cervical neoplasms, but consume immense healthcare costs. The spice component curcumin has potent anticancer and antiviral properties, which have been difficult to harness as a treatment, due to its poor systemic bioavailability. This project tests the possibility of developing a curcumin-based therapy for cervical cancer. METHODS:  Using four HPV(+) cervical cancer cell lines and normal fibroblasts we first tested the selectivity and potency of curcumin in eliminating HPV(+) cells. Subsequently, we developed a curcumin-based cervical cream and tested its efficacy in eliminating apposed HPV(+) cells and also its possible side effects on the vaginal epithelium of healthy mice. RESULTS:  Curcumin selectively eliminates a variety of HPV(+) cervical cancer cells (HeLa, ME-180, SiHa, and SW756), suppresses the transforming antigen E6, dramatically inhibits the expression of the pro-cancer protein epidermal growth factor receptor (EGFR), and concomitantly induces p53. Additionally, Vacurin, a uniform colloidal solution of curcumin in a clinically used amphipathic vaginal cream, eliminates apposed HeLa cells while suppressing the expression of EGFR. In mice, daily intravaginal application of Vacurin for three weeks produced no change in body weight and when the mice were sacrificed, the vaginal tract epithelium showed no Vacurin-evoked adverse effects. CONCLUSION:  We have developed a curcumin-based vaginal cream, which effectively eradicates HPV(+) cancer cells and does not affect non-cancerous tissue. Our preclinical data support a novel approach for the treatment of cervical HPV infection.

Monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, and curcumin: a randomized, double-blind placebo-controlled cross-over 4g study and an open-label 8g extension study.
            (Golombick et al., 2012) Download
Monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) represent useful models for studying multiple myeloma precursor disease, and for developing early intervention strategies. Administering a 4g dose of curcumin, we performed a randomised, double-blind placebo-controlled cross-over study, followed by an open-label extension study using an 8g dose to assess the effect of curcumin on FLC response and bone turnover in patients with MGUS and SMM. 36 patients (19 MGUS and 17 SMM) were randomised into two groups: one received 4g curcumin and the other 4g placebo, crossing over at 3 months. At completion of the 4g arm, all patients were given the option of entering an open-label, 8g dose extension study. Blood and urine samples were collected at specified intervals for specific marker analyses. Group values are expressed as mean ± 1 SD. Data from different time intervals within groups were compared using Student's paired t-test. 25 patients completed the 4g cross-over study and 18 the 8g extension study. Curcumin therapy decreased the free light-chain ratio (rFLC), reduced the difference between clonal and nonclonal light-chain (dFLC) and involved free light-chain (iFLC). uDPYD, a marker of bone resorption, decreased in the curcumin arm and increased on the placebo arm. Serum creatinine levels tended to diminish on curcumin therapy. These findings suggest that curcumin might have the potential to slow the disease process in patients with MGUS and SMM.

Comparison of oxaliplatin- and curcumin-mediated antiproliferative effects in colorectal cell lines.
            (Howells et al., 2007) Download
Colorectal cancer remains a leading cause of cancer death worldwide, despite markedly improved response rates to current systemic therapies. Oxaliplatin either alone or incorporated into 5-fluorouracil/leucovorin regimes has resulted in increased survival rates, particularly with regards to metastatic colorectal carcinoma. The chemopreventive polyphenol curcumin, which is currently in clinical trial, has been advocated for use in colorectal cancer either singly or in combination with chemotherapeutic drugs. In this study, the antiproliferative capacity of both compounds was compared in HCEC (normal-derived), HT29 (p53 mutant adenocarcinoma) and HCT116 (p53wt adenocarcinoma) colorectal cell lines to determine whether effects were cell-type specific at pharmacologically achievable doses, and whether the combination resulted in enhanced efficacy. Both oxaliplatin and curcumin displayed marked antiproliferative capacity at therapeutic concentrations in the two tumor cell lines. Order of sensitivity to oxaliplatin was HCT116>HT29>HCEC, whereas order of sensitivity to curcumin was HT29>HCT116>HCEC. HCT116 cells underwent induction of G2/M arrest in response to both oxaliplatin (irreversible) and curcumin (reversible). Apoptosis was induced by both agents, and up to 16-fold induction of p53 protein was observed in response to the combination. Antiproliferative effects in HT29 cells were largely cell cycle independent, and were mediated by induction of apoptosis. Effects were greatly enhanced in both cell lines when agents were combined. This study provides further evidence that curcumin may be of use in therapeutic regimes directed against colorectal cancer, and suggests that in combination with oxaliplatin it may enhance efficacy of the latter in both p53wt and p53 mutant colorectal tumors.

Curcumin inhibits cancer stem cell phenotypes in ex vivo models of colorectal liver metastases, and is clinically safe and tolerable in combination with FOLFOX chemotherapy.
            (James et al., 2015) Download
In vitro and pre-clinical studies have suggested that addition of the diet-derived agent curcumin may provide a suitable adjunct to enhance efficacy of chemotherapy in models of colorectal cancer. However, the majority of evidence for this currently derives from established cell lines. Here, we utilised patient-derived colorectal liver metastases (CRLM) to assess whether curcumin may provide added benefit over 5-fluorouracil (5-FU) and oxaliplatin (FOLFOX) in cancer stem cell (CSC) models. Combination of curcumin with FOLFOX chemotherapy was then assessed clinically in a phase I dose escalation study. Curcumin alone and in combination significantly reduced spheroid number in CRLM CSC models, and decreased the number of cells with high aldehyde dehydrogenase activity (ALDH(high)/CD133(-)). Addition of curcumin to oxaliplatin/5-FU enhanced anti-proliferative and pro-apoptotic effects in a proportion of patient-derived explants, whilst reducing expression of stem cell-associated markers ALDH and CD133. The phase I dose escalation study revealed curcumin to be a safe and tolerable adjunct to FOLFOX chemotherapy in patients with CRLM (n = 12) at doses up to 2 grams daily. Curcumin may provide added benefit in subsets of patients when administered with FOLFOX, and is a well-tolerated chemotherapy adjunct.

Targeting breast stem cells with the cancer preventive compounds curcumin and piperine.
            (Kakarala et al., 2010) Download
The cancer stem cell hypothesis asserts that malignancies arise in tissue stem and/or progenitor cells through the dysregulation or acquisition of self-renewal. In order to determine whether the dietary polyphenols, curcumin, and piperine are able to modulate the self-renewal of normal and malignant breast stem cells, we examined the effects of these compounds on mammosphere formation, expression of the breast stem cell marker aldehyde dehydrogenase (ALDH), and Wnt signaling. Mammosphere formation assays were performed after curcumin, piperine, and control treatment in unsorted normal breast epithelial cells and normal stem and early progenitor cells, selected by ALDH positivity. Wnt signaling was examined using a Topflash assay. Both curcumin and piperine inhibited mammosphere formation, serial passaging, and percent of ALDH+ cells by 50% at 5 microM and completely at 10 microM concentration in normal and malignant breast cells. There was no effect on cellular differentiation. Wnt signaling was inhibited by both curcumin and piperine by 50% at 5 microM and completely at 10 microM. Curcumin and piperine separately, and in combination, inhibit breast stem cell self-renewal but do not cause toxicity to differentiated cells. These compounds could be potential cancer preventive agents. Mammosphere formation assays may be a quantifiable biomarker to assess cancer preventive agent efficacy and Wnt signaling assessment can be a mechanistic biomarker for use in human clinical trials.

A phase I/II study of gemcitabine-based chemotherapy plus curcumin for patients with gemcitabine-resistant pancreatic cancer.
            (Kanai et al., 2011) Download
PURPOSE:  Curcumin, a plant-derived natural polyphenol, could be a promising anti-cancer drug and shows synergic effects with cytotoxic agents. We evaluated the safety and feasibility of combination therapy using curcumin with gemcitabine-based chemotherapy. METHODS:  Gemcitabine-resistant patients with pancreatic cancer received 8 g oral curcumin daily in combination with gemcitabine-based chemotherapy. The primary endpoint was safety for phase I and feasibility of oral curcumin for phase II study. RESULTS:  Twenty-one patients were enrolled. No dose-limiting toxicities were observed in the phase I study and oral curcumin 8 g/day was selected as the recommended dose for the phase II study. No patients were withdrawn from this study because of the intolerability of curcumin, which met the primary endpoint of the phase II study, and the median compliance rate of oral curcumin was 100% (Range 79-100%). Median survival time after initiation of curcumin was 161 days (95% confidence interval 109-223 days) and 1-year survival rate was 19% (4.4-41.4%). Plasma curcumin levels ranged from 29 to 412 ng/ml in five patients tested. CONCLUSIONS:  Combination therapy using 8 g oral curcumin daily with gemcitabine-based chemotherapy was safe and feasible in patients with pancreatic cancer and warrants further investigation into its efficacy.

Curcumin as a possible lead compound against hormone-independent, multidrug-resistant breast cancer.
            (Labbozzetta et al., 2009) Download
We examine the possible evidence that the phytochemical curcumin may overcome resistance to hormonal and cytotoxic agents in breast cancer. We present our observations on MCF-7R, a multidrug-resistant (MDR) variant of the MCF-7 breast cancer cell line. In contrast to MCF-7, MCF-7R lacks aromatase and estrogen receptor alpha (ERalpha) and overexpresses the multidrug transporter ABCB1 and the products of different genes implicated in cell proliferation and survival, like c-IAP-1, NAIP, survivin, and COX-2. Nevertheless, in cytotoxicity and cell death induction assays, we found that the antitumor activity of curcumin is substantial both in MCF-7 and in MCF-7R. We elaborated the diketone system of curcumin into different analogues; the benzyloxime and the isoxazole and pyrazole heterocycles showed remarkable increases in the antitumor potency both in the parental and in the MDR MCF-7 cells. Furthermore, curcumin or, more potently, the isoxazole analogue, produced early reductions in the amounts of relevant gene transcripts that were diverse (i.e., they were relative to Bcl-2 and Bcl-X(L) in MCF-7 and the inhibitory of apoptosis proteins and COX-2 in MCF-7R) in the two cell lines. Thus, the two compounds exhibited the remarkable property of being able to modify their molecular activities according to the distinct characteristics of the parental and MDR cells. We discuss also how curcumin may (1) exert antitumor effects in breast cancer through ER-dependent and ER-independent mechanisms; and (2) act as a drug transporter-mediated MDR reversal agent. Overall, the structure of curcumin may represent the basis for the development of new, effective anticancer agents in hormone-independent MDR breast cancer.

The New Combination Docetaxel, Prednisone and Curcumin in Patients with Castration-Resistant Prostate Cancer: A Pilot Phase II Study.
            (Mahammedi et al., 2016) Download
OBJECTIVES:  Favorable phase I results justified this pilot phase II study to assess the efficacy of docetaxel/curcumin in patients with chemotherapy-naive metastatic castration-resistant prostate cancer (CRPC). METHODS:  Thirty patients with progressing CRPC and a rising prostate-specific antigen (PSA) received docetaxel/prednisone in standard conditions for 6 cycles in combination with per os curcumin, 6,000 mg/day (day -4 to day +2 of docetaxel). The co-primary endpoint was the overall response rate determined by PSA and target assessments. An ancillary study assessed the seric values of chromogranin A (CgA) and neuron-specific enolase (NSE). RESULTS:  Twenty-six patients received the scheduled treatment, 2 progressed and 2 died before the end of treatment. A PSA response was observed in 59% of patients (14% of PSA normalization) and achieved within the first three cycles for 88% of responders. Partial response was reached for 40% of evaluable patients. The regimen was well tolerated, and no adverse event was attributed to curcumin. Twenty patients were 100% curcumin compliant. The PSA level and objective response rate were not correlated with the serum values of CgA and NSE. CONCLUSION:  This study produced additional data on curcumin as a treatment for cancer, with a high response rate, good tolerability and patient acceptability, justifying the interest to conduct a randomized trial.

Inhibitory effect of curcumin on uterine leiomyoma cell proliferation.
            (Tsuiji et al., 2011) Download
OBJECTIVE:  Uterine leiomyomas are the most common gynaecological benign tumour and greatly affect reproductive health and wellbeing. They are the predominant indication for hysterectomy in premenopausal women. Curcumin, a well-known component of turmeric, has been reported to prevent various diseases such as cancer, diabetes and obesity. Previous study reported that curcumin represses the proliferation of several tumour cells. However, there has not been a precise characterisation of the curcumin-induced inhibition of uterine leiomyoma cells. In this study, we investigated the inhibitory effect of curcumin on leiomyoma cells proliferation. STUDY DESIGN:  Eker rat-derived uterine leiomyoma cell lines (ELT-3 cells) were used. Cell proliferation was assessed by counting the number of cells and MTS assay. The activation of peroxisome proliferator-activated receptor-gamma (PPARγ) was evaluated by luciferase assay. RESULTS:  We found that curcumin significantly inhibited ELT-3 cell proliferation. PPARγ was expressed in ELT-3 cells and curcumin acted as a PPARγ ligand. This inhibitory effect of curcumin was attenuated by the treatment of cells with PPARγ antagonist. CONCLUSION:  These experimental findings in vitro show that the inhibitory effect of curcumin on ELT-3 cell proliferation occurs through the activation of PPARγ. Curcumin may be useful as an alternative therapy for uterine leiomyoma.



Almanaa, TN, ME Geusz, and RJ Jamasbi (2012), ‘Effects of curcumin on stem-like cells in human esophageal squamous carcinoma cell lines.’, BMC Complement Altern Med, 12 195. PubMed: 23095512
Basu, P, et al. (2013), ‘Clearance of cervical human papillomavirus infection by topical application of curcumin and curcumin containing polyherbal cream: a phase II randomized controlled study.’, Asian Pac J Cancer Prev, 14 (10), 5753-59. PubMed: 24289574
Carroll, RE, et al. (2011), ‘Phase IIa clinical trial of curcumin for the prevention of colorectal neoplasia.’, Cancer Prev Res (Phila), 4 (3), 354-64. PubMed: 21372035
Debata, PR, et al. (2013), ‘A novel curcumin-based vaginal cream Vacurin selectively eliminates apposed human cervical cancer cells.’, Gynecol Oncol, 129 (1), 145-53. PubMed: 23234806
Golombick, T, et al. (2012), ‘Monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, and curcumin: a randomized, double-blind placebo-controlled cross-over 4g study and an open-label 8g extension study.’, Am J Hematol, 87 (5), 455-60. PubMed: 22473809
Howells, LM, A Mitra, and MM Manson (2007), ‘Comparison of oxaliplatin- and curcumin-mediated antiproliferative effects in colorectal cell lines.’, Int J Cancer, 121 (1), 175-83. PubMed: 17330230
James, MI, et al. (2015), ‘Curcumin inhibits cancer stem cell phenotypes in ex vivo models of colorectal liver metastases, and is clinically safe and tolerable in combination with FOLFOX chemotherapy.’, Cancer Lett, 364 (2), 135-41. PubMed: 25979230
Kakarala, M, et al. (2010), ‘Targeting breast stem cells with the cancer preventive compounds curcumin and piperine.’, Breast Cancer Res Treat, 122 (3), 777-85. PubMed: 19898931
Kanai, M, et al. (2011), ‘A phase I/II study of gemcitabine-based chemotherapy plus curcumin for patients with gemcitabine-resistant pancreatic cancer.’, Cancer Chemother Pharmacol, 68 (1), 157-64. PubMed: 20859741
Labbozzetta, M, et al. (2009), ‘Curcumin as a possible lead compound against hormone-independent, multidrug-resistant breast cancer.’, Ann N Y Acad Sci, 1155 278-83. PubMed: 19250217
Mahammedi, H, et al. (2016), ‘The New Combination Docetaxel, Prednisone and Curcumin in Patients with Castration-Resistant Prostate Cancer: A Pilot Phase II Study.’, Oncology, 90 (2), 69-78. PubMed: 26771576
Tsuiji, K, et al. (2011), ‘Inhibitory effect of curcumin on uterine leiomyoma cell proliferation.’, Gynecol Endocrinol, 27 (7), 512-17. PubMed: 20672906