Colloidal silver has been used as an antimicrobial and disinfectant agent. However, there is scarce information on its antitumor potential. The aim of this study was to determine if colloidal silver had cytotoxic effects on MCF-7 breast cancer cells and its mechanism of cell death.

The development of new nanomaterials to promote wound healing is rising, because of their topical administration and easy functionalization with molecules that can improve and accelerate the process of healing. A nanocomposite of gold nanoparticles (AuNPs) functionalized with calreticulin was synthetized and evaluated. The ability of the nanocomposite to promote proliferation and migration was determined in vitro, and in vivo wound healing was evaluated using a mice model of diabetes established with streptozotocin (STZ). In vitro, the nanocomposite not affect the cell viability and the expression of proliferating cell nuclear antigen (PCNA). Moreover, the nanocomposite promotes the clonogenicity of keratinocytes, endothelial cells, and fibroblasts, and accelerates fibroblast migration. In vivo, mice treated with the nanocomposite presented significantly faster wound healing. The histological evaluation showed re-epithelization and the formation of granular tissue, as well as an increase of collagen deposition. Therefore, these results confirm the utility of AuNPs–calreticulin nanocomposites as potential treatment for wound healing of diabetic ulcers.

Bovine dialyzable leukocyte extract (bDLE) is a dialyzate of a heterogeneous mixture of low molecular weight substances released from disintegrated blood leukocytes or lymphoid tissue obtained from homogenized bovine spleen. The purpose of this study was to determine if bDLE had cytotoxic effects and modulated apoptosis gene expression in breast cancer cells. The MCF-7, BT-474, MDA-MB-453, A-427, Calu-1, U937 and L5178Y cancer cell lines and PBMC human cells were treated with bDLE (0–0.66 U/mL) for 72 h. The bDLE effect on cell growth proliferation was evaluated by MTT assay, and the MCF-7 was evaluated by ethidium bromide–acridine orange staining; total DNA was evaluated for DNA fragmentation, and total RNA was isolated for p53, bag-1, c-myc, bim, bax, bcl-2 and bad mRNA expression. The bDLE had dose-dependent cytotoxic effects and demonstrated an IC₅₀ at a dosage of 0.06 U/mL (P < 0.05). The bDLE did not affect the viability of normal human PBMC. The bDLE induced DNA fragmentation at doses of 0.06 and 0.13 U/mL in MCF-7 breast cancer cells. The bDLE induced cytotoxic effects and suppressed the p53, bag-1, c-myc, bax, bcl-2, and bad mRNA expression that influences apoptosis in MCF-7 breast cancer cells. Bim mRNA expression was not detected. This may open up interesting prospects for the treatment of human breast cancer.

Biomaterials are often used in orthopedic surgery like cavity fillings. However, related complications often require long-term systemic antibiotics, device removal, and extended rehabilitation. Hydroxyapatite/silver (HA/Ag) composites have been proposed as implantation biomaterials owing to the osteogenic properties of hydroxyapatite and to the antimicrobial efficiency of silver. Nevertheless, higher silver concentrations induce cytotoxic effects. The aim of this study was to synthesize and characterize HA/Ag nanocomposites that will allow us to use lower concentrations of silver nanoparticles with better antimicrobial efficiency and anti-inflammatory properties. The characterization of HA/Ag was performed by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Fourier-transform infrared spectra, X-ray photoelectron spectroscopy, and laser diffraction. Bioactivity was evaluated under a simulated body fluid. The viability of osteoblast like-cells (MG-63) was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) and the antimicrobial activity was evaluated by the standard McFarland method. The detection of nitric oxide was measured by a colorimetric assay and the inflammatory cytokines by flow cytometry. We obtained particulate composites of calcium phosphates identified as hydroxyapatite and silver nanoparticles. The bioactivity of the HA/Ag nanocomposites on SFB was confirmed by apatite formations. The viability of MG-63 cells was not affected. We also found antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans owing to the presence of silver nanoparticles at non-cytotoxic concentrations. HA/Ag reduced the release of nitric oxide and decreased the secretion of IL-1 and TNF-α in cells stimulated with Lipopolysaccharide (LPS). In conclusion, the inflammatory and antimicrobial capacity of the HA/Ag nanocomposites, as well as its bioactivity and low cytotoxicity make it a candidate as an implantation biomaterial for bone tissues engineering and clinical practices in orthopedic, oral and maxillofacial surgery.

Immunogenic cell death is a cell death modality that stimulates the immune system to combat cancer cells. IMMUNEPOTENT CRP (ICRP) is a mixture of substances of low molecular weight obtained from bovine spleens that exhibits in vitro cytotoxic activity on different tumor cell lines and modulates the immune response in vivo. The aim of the present study was to determine whether the cytotoxic effect of ICRP and its combination with oxaliplatin (OXP) on murine melanoma B16F10 cells was due to immunogenic cell death. The cytotoxic assay was performed using flow cytometry to detect Annexin V and propidium iodide staining, and calreticulin (CRT) exposure. Adenosine triphosphate, heat shock protein (HSP) 70, HSP90 and high mobility group box 1 (HMGB1) release were identified using bioluminescence, western blot and ELISA assays, respectively. The present in vitro study demonstrated that treatments with ICRP or OXP induced cell death in a time-dependent manner, but treatment with the combination of ICRP + OXP increased the cytotoxic effect following 24 h of treatment. CRT exposure and release of adenosine triphosphate (ATP), HSP70, HSP90 and HMGB1 were induced by treatment with ICRP, and the combination of ICRP + OXP increased the exposure and release of damage-associated molecular patterns (DAMPs), while OXP treatment only induced CRT exposure, ATP and HMGB1 release. The in vivo experiments demonstrated that administration of tumor-derived DAMP-rich cell lysates derived from B16F10 cells treated with ICRP and the combination of ICRP + OXP prevented melanoma growth; however, OXP treatment did not. These results suggested that IMMUNEPOTENT CRP may be used as an agent to increase the ability of antitumor drugs to induce immunogenic cell death and prevent the growth of melanoma.