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Colorectal cancer is one of the most significant types of cancer, ranking second in the world's mortality cases. As colorectal cancer is often diagnosed at a late stage of disease progression, effective treatments are necessary. Therefore, radiotherapy has become a fundamental approach in the treatment of colorectal cancer, especially those based on the use of 177 Lu. A potential approach to meet this challenge is the use of nanotechnology through the development of radionuclide-based nanomaterials. In this work, we investigated a SiO 2 -derived class of nanomaterials formed by the insertion of the coordination complex, based on Eu 3+ and pyrimidine-2,6-dicarboxylic acid (DPA), into nanoparticles of amino-functionalized mesoporous silica (EuDPA/SiO 2 −NH 2 ). The properties of the EuDPA/SiO 2 −NH 2 nanoparticles were initially investigated by SEM, FT-IR, TGA, and luminescence. The cellular uptake of EuDPA/SiO 2 −NH 2 nanoparticles into HT-29 cells was confirmed by fluorescence microscopy. Radioactivity was incorporated into the EuDPA/SiO 2 −NH 2 nanoparticles by replacing a tracer quantity of Eu 3+ sites with the lanthanide element 177 Lu, which resulted in the composition of a dual-modality probe for both SPECT imaging and tumor radiotherapy. Analysis of 177 Lu loading into EuDPA/SiO 2 −NH 2 particles showed efficient incorporation, up to 93% radioactivity into the final compound. The imaging potential of the 177 Lu−EuDPA/SiO 2 −NH 2 nanoparticles was investigated by SPECT/CT imaging, a subcutaneous HT-29 mouse model of colorectal cancer. Image analysis showed that tumor localization was maintained after intratumoral administration for up to 48 h. To evaluate the therapeutic potential of 177 Lu−EuDPA/SiO 2 −NH 2 nanoparticles, HT-29 xenografts were treated in vivo by direct intratumoral injection. Compared with control (PBS) treatment or treatment with unlabeled EuDPA/SiO 2 −NH 2 nanoparticles, the treatment with 177 Lu−EuDPA/SiO 2 −NH 2 nanoparticles resulted in a significantly reduced tumor growth. Together, the results of this study results indicate that 177 Lu−EuDPA/SiO 2 −NH 2 is a promising agent for further development in SPECT imaging and clinical treatment of colorectal cancer.

The objective of this study was to find the optimum dose of flaxseed that would decrease prostaglandins and alter estrogen pathway endpoints implicated in ovarian cancer. Fifty 1.5-year-old chickens per group were fed different percentages of flaxseed (5%, 10%, 15%) for four months then sacrificed to collect blood and tissues. Levels of flaxseed lignan metabolites, Enterolactone (EL) and Enterodiol (ED), were measured in the serum, liver and ovaries by LC-MS/MS while omega-3 and 6 fatty acid levels were measured by GC. Effect of varying flaxseed doses was assessed by measuring levels of prostaglandin E2, estrogen metabolites (16-hydroxyestrone (16-OHE1), 2-hydroxyestrone (2-OHE1)) and analyzing the expression of E2 metabolizing enzymes (CYP3A4, CYP1B1, CYP1A1) and ERα in the ovaries. The ratio of omega-3 fatty acids/ omega-6 fatty acids increased with increase in flaxseed supplementation of diet corresponding to a dose dependent decrease in COX-2 protein and prostaglandin E2 levels. EL and ED increased in the liver, ovary and serum with increasing concentrations of flaxseed. Flaxseed decreased the expression of ERα in the ovary. The ratio of 2-hydroxyestrone to 16-hydroxyestrone in the serum increased significantly in the 15% flaxseed diet with a corresponding increase in CYP1A1 in the liver and a decrease in CYP3A4 in the ovary, respectively. CYP1B1 mRNA also decreased with flaxseed diet in the ovary. The 15% flaxseed supplemented diet significantly decreased inflammatory prostaglandin E2, ERα, CYP3A4, CYP1B1 and 16-OHE1 while it increased CYP1A1 and 2-OHE1, thus reducing the inflammatory and pro-carcinogenic microenvironment of the ovary.

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Polyaniline-decorated ZIF-8 nanoparticles (nPANI@nZIF-8) were easily synthesized and employed as a multifunctional system for the delivery of the antitumor drug 5-fluorouracil (5-FU). Because of the storage ability of the network ZIF-8, 68% of the total amount of the 5-FU drug was released at pH 5.2. The system exhibits absorption in the near-infrared (NIR) region and can be used in the photothermal therapy owing to the presence of nPANI, which has a strong NIR uptake. This absorption causes local hyperthermia by aiding in the diffusion of the drug molecules contained by the polymer into nPANI@nZIF-8/5-FU achieving a greater release of the 5-FU drug, about 80% activated by an NIR laser (λ = 980 nm). This hyperthermia reached about 70 °C (200 μL, 1 mg mL–1 nPANI@nZIF-8), which was directly proportional to the concentration of the material. Therefore, our work can aid in the construction of new chemo-photothermal platforms that may be employed in cancer therapy.