Objectives: Recently, we have isolated koetjapic acid (KA) from Sandoricum koetjape and identified its selective anticancer potentiality against colorectal carcinoma. KA is quite likely to be useful as a systemic anticancer agent against colorectal malignancy. However, with extremely low solubility, KA has to be converted into a biocompatible solubilized form without compromising the bioefficacy. Objective of this study is to enhance solubility of KA and to evaluate anticancer efficacy of potassium koetjapate in human colorectal cancer cells. Methods: (2-Hydroxypropyl)-β-cyclodextrin inclusion complex and solid dispersions (carboxymethyl cellulose, polyvinylpyrrolidone and sodium lauryl sulphate) of KA were prepared. In addition, a salt of KA, potassium koetjapate was synthesized. Key findings: Potassium koetjapate demonstrated higher solubility than the other tested formulations with enhanced cytotoxicity against HCT 116 cells. The enhanced efficacy of potassium koetjapate is attributed to apoptotic induction of nuclear condensation and disruption of mitochondrial membrane potential in the cells. Interestingly, potassium koetjapate was found to be safe in rats after oral administration (LD50 > 2000 mg/kg). Conclusions: The salt formulation of KA appears to modulate the capability of the parent compound by enhancing its solubility and improves its bioefficacy against colon cancer cells, suggesting attractive roles for its applications in medicine.

This paper describes synthesis, characterization (NMR, FT‐IR, microanalysis, and X‐ray crystallography), in vitro anticancer activity of ortho/para‐xylyl linked bis‐imidazolium salts (4‐5) and respective dinuclear Ag(I) N‐heterocyclic carbene (NHC) complexes (6‐7). All the compounds were tested for their cytotoxicity against human colorectal cancer (HCT 116) and breast cancer (MCF‐7) cell lines. According to cell viability measurements using MTT assay, all the complexes (6‐7) showed a dose‐dependent cytotoxic activity against both the cell lines, whereas respective salts (4‐5) proved to be inactive. The complexes (6‐7) demonstrated significant activity with IC₅₀ values range 5.6–20.3 μM for HCT 116 and 1.12–6.38 μM for MCF‐7. 5‐Fluorouracil was used as standard drug (IC₅₀ = 5.9 μM) for HCT 116, whereas tamoxifen was used as standard drug for MCF‐7 (IC₅₀ = 14 μM) cell line.

Koetjapic acid is an active compound of a traditional medicinal plant, Sandoricum koetjape. Although koetjapic acid has a promising anticancer potential, yet it is highly insoluble in aqueous solutions. To increase aqueous solubility of koetjapic acid, we have previously reported a chemical modification of koetjapic acid to potassium koetjapate (KKA). However, pharmacokinetics of KKA has not been studied. In this study, pharmacokinetics and antiangiogenic efficacy of KKA are investigated. Pharmacokinetics of KKA was studied after intravenous and oral administration in SD rats using HPLC. Anti-angiogenic efficacy of KKA was investigated in rat aorta, human endothelial cells (EA.hy926) and nude mice implanted with matrigel. Pharmacokinetic study revealed that KKA was readily absorbed into blood and stayed for a long time in the body with T_max 2.89 ± 0.12 h, C_max 7.24 ± 0.36 μg/mL and T_1/2 1.46 ± 0.03 h. The pharmacological results showed that KKA significantly suppressed sprouting of microvessels in rat aorta with IC₅₀ 18.4 ± 4.2 μM and demonstrated remarkable inhibition of major endothelial functions such as migration, differentiation and VEGF expression in endothelial cells. Further, KKA significantly inhibited vascularization in matrigel plugs implanted in nude mice. The results indicate that bioabsorption of KKA from oral route was considerably efficient with longer retention in body than compared to that of the intravenous route. Further, improved antiangiogenic activity of KKA was recorded which could probably be due to its increased solubility and bioavailability. The results revealed that KKA inhibits angiogenesis by suppressing endothelial functions and expression of VEGF.

Azolium (imidazolium and benzimidazolium) salts are known as stable precursors for the synthesis of Metal-N-Heterocyclic Carbene (M-NHC) complexes. Recently, some reports have been compiled indicating that benzimidazolium salts have anticarcinogenic properties. The current research is the further investigation of this phenomenon. Three ortho-xylene linked bis-benzimidazolium salts (1-3) with octyl, nonyl and decyl terminal chain lengths have been synthesized. Each of the compounds was characterized using FT-IR and NMR spectroscopic techniques. The molecular geometries of two of the salts (1-2) have been established using X-ray crystallographic technique. The compounds were tested for their cytotoxic properties against three cancerous cell lines namely, human colon cancer (HCT 116), human colorectal adenocarcinoma (HT- 29) and human breast adenocarcinoma (MCF-7). Mouse embryonic fibroblast (3T3-L1) was used as the model cell line of normal cells. The compounds showed selective anti-proliferative activities against the colorectal carcinoma cells. For HCT 116 and HT-29 cells, the IC₅₀ values ranged 0.9-2.6 µM and 4.0-10.0 µM, respectively. The salts 1 and 3 displayed moderate cytotoxicity against the breast cancer (MCF-7) cells with IC₅₀ 58.2 and 13.3 µM, respectively. However, the salt 2 produced strong cytotoxicity against MCF-7 cells with IC₅₀ 4.4 µM. Interestingly, the compounds demonstrated poor cytotoxic effects towards the normal cells (3T3-L1) as the IC₅₀ was found to be as high as 48.0 µM. Salts 2 and 3 demonstrated more pronounced anti-proliferative effect than the standard drugs used (5-Flourouracil and Tamoxifen).

Background and purpose: The previous work on koetjapic acid (KA) isolated from Sandoricum koetjape showed its efficacy towards colorectal cancer however KA has poor water solubility which poses the biggest hindrance to its efficacy. In the present paper, an attempt was made to study the anti-colon cancer efficacy of KA’s potassium salt i.e. potassium koetjapate (KKA) applying in vitro and in vivo methods. Experimental approach: KKA was produced by a semi-synthetic method. A human apoptosis proteome profiler array was applied to determine the protein targets responsible for the stimulation of apoptosis. Three doses of KKA were studied in athymic nude mice models to examine the in vivo anti-tumorigenic ability of KKA. Findings/Results: The results of this study demonstrated that KKA regulates the activities of various proteins. It downregulates the expression of several antiapoptotic proteins and negative regulators of apoptosis including HSP60, HSP90, Bcl-2, and IGF-1 in HCT 116 cells with consequent upregulation of TRAILR-1 and TRAILR-2, p27, CD40, caspase 3, and caspase 8 proteins. Additionally, KKA showed an in vitro antimetastatic effect against HCT 116 cells. These results are feasibly related to the down-regulation of Notch, Wnt, hypoxia, and MAPK/JNK and MAPK/ERK signalling pathways in HCT 116 cells besides the up-regulation of a transcription factor for cell cycle (pRb-E2F) pathways. In addition, KKA revealed potent inhibition of tumor growth. Conclusion and implications: In sum, the findings indicate that KKA can be a promising candidate as a chemotherapeutic agent against colorectal cancer.