trans-sodium-crocetinate and Pancreatic-Neoplasms

Pancreatic cancer is the fourth leading cause of cancer deaths in the US and no significant treatment is currently available. Here, we describe the effect of crocetinic acid, which we purified from commercial saffron compound crocetin using high performance liquid chromatography. Crocetinic acid inhibits proliferation of pancreatic cancer cell lines in a dose- and time-dependent manner. In addition, it induced apoptosis. Moreover, the compound significantly inhibited epidermal growth factor receptor and Akt phosphorylation. Furthermore, crocetinic acid decreased the number and size of the pancospheres in a dose-dependent manner, and suppressed the expression of the marker protein DCLK-1 (Doublecortin Calcium/Calmodulin-Dependent Kinase-1) suggesting that crocetinic acid targets cancer stem cells (CSC). To understand the mechanism of CSC inhibition, the signaling pathways affected by purified crocetinic acid were dissected. Sonic hedgehog (Shh) upon binding to its cognate receptor patched, allows smoothened to accumulate and activate Gli transcription factor. Crocetinic acid inhibited the expression of both Shh and smoothened. Finally, these data were confirmed in vivo where the compound at a dose of 0.5 mg/Kg bw suppressed growth of tumor xenografts. Collectively, these data suggest that purified crocetinic acid inhibits pancreatic CSC, thereby inhibiting pancreatic tumorigenesis.

Topics: Animals; Apoptosis; Carotenoids; Cell Line, Tumor; Cell Movement; Cell Proliferation; Chromatography, High Pressure Liquid; Crocus; Dose-Response Relationship, Drug; Doublecortin-Like Kinases; Female; Hedgehog Proteins; Humans; Intracellular Signaling Peptides and Proteins; Mice; Mice, Nude; Neoplasm Transplantation; Neoplastic Stem Cells; Pancreatic Neoplasms; Phosphorylation; Plant Extracts; Protein Serine-Threonine Kinases; Receptors, G-Protein-Coupled; Shc Signaling Adaptor Proteins; Signal Transduction; Smoothened Receptor; Spheroids, Cellular; Src Homology 2 Domain-Containing, Transforming Protein 2; Vitamin A

Crocetin, a carotenoid compound derived from saffron, has long been used as a traditional ancient medicine against different human diseases including cancer. The aim of the series of experiments was to systematically determine whether crocetin significantly affects pancreatic cancer growth both in vitro and/or in vivo. For the in vitro studies, first, MIA-PaCa-2 cells were treated with crocetin and in these sets of experiments, a proliferation assay using H(3)-thymidine incorporation and flow cytometric analysis suggested that crocetin inhibited proliferation. Next, cell cycle proteins were investigated. Cdc-2, Cdc-25C, Cyclin-B1, and epidermal growth factor receptor were altered significantly by crocetin. To further confirm the findings of inhibition of proliferation, H(3)-thymidine incorporation in BxPC-3, Capan-1, and ASPC-1 pancreatic cancer cells was also significantly inhibited by crocetin treatment. For the in vivo studies, MIA-PaCa-2 as highly aggressive cells than other pancreatic cancer cells used in this study were injected into the right hind leg of the athymic nude mice and crocetin was given orally after the development of a palpable tumor. The in vivo results showed significant regression in tumor growth with inhibition of proliferation as determined by proliferating cell nuclear antigen and epidermal growth factor receptor expression in the crocetin-treated animals compared with the controls. Both the in vitro pancreatic cancer cells and in vivo athymic nude mice tumor, apoptosis was significantly stimulated as indicated by Bax/Bcl-2 ratio. This study indicates that crocetin has a significant antitumorigenic effect in both in vitro and in vivo on pancreatic cancer.

Topics: Animals; Antineoplastic Agents; Apoptosis; Carotenoids; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Disease Progression; ErbB Receptors; Female; Humans; Mice; Mice, Nude; Neoplasm Proteins; Pancreatic Neoplasms; Proliferating Cell Nuclear Antigen; Vitamin A; Xenograft Model Antitumor Assays