Multiparametric analysis of the effectiveness of cisplatin on cutaneous squamous carcinoma cells using two different types of adjuvants.

The objective of this study was to regulate the cytotoxicity of cisplatin (cisPt) minimizing its adverse effects. For this purpose, the lowest cisPt concentration needed to obtain a significant positive response in cutaneous squamous cell carcinoma (cSCC) was explored. Two adjuvant agents as gold nanoparticles (AuNP) and chelating tricine were tested as enhancers in cisPt treatment. Effectiveness of all treatments was assessed by means of biochemical techniques, which offer quantitative data, as well as two microscopy-based techniques that provided qualitative cell imaging. The present work confirms the effectiveness of free cisplatin at very low concentrations. In order to enhance its effectiveness while the side effects were probably diminished, cisPt 3.5 µM was administered with AuNP 2.5 mM, showing an effectiveness practically equal to that observed with free cisPt. However, the second treatment investigated, based on cisPt 3.5 µM combined with tricine 50 mM, enhanced drug effectiveness, increasing the percentage of cells dying by apoptosis. This treatment was even better in terms of cell damage than free cisPt at 15 µM. Images obtained by TEM and cryo-SXT confirmed these results, since a notable number of apoptotic bodies were detected when cisPt was combined with tricine. Thus, tricine was clearly a better adjuvant for cisPt treatments.

Measurement by nuclear magnetic resonance diffusion of the dimensions of the mobile lipid compartment in C6 cells.

The (1)H spectrum of certain tumor cells, in vivo tumors, and their biopsies in vitro shows a narrow and intense resonance at 1.26 ppm, which has been assigned to the fatty acyl chain of triglycerides [nuclear magnetic resonance (NMR) visible mobile lipids, MLs]. We have used diffusion-weighted NMR spectroscopy to directly address the subcellular origin of MLs in the case of C6 cells in which lactate accumulation had been inhibited by prior iodoacetamide incubation. Borage oil and artificial lipid droplets were used as model systems of free and restricted diffusion, respectively. The characteristic diameter for the ML resonance compartment measured by NMR for the C6 cells was not significantly different from the one obtained with phase contrast microscopy (1.88 +/- 0.04 micro m from NMR versus 1.37 +/- 0.33 micro m from microscopy). We herewith provide direct and noninvasive evidence that the lipid signal at 1.26 ppm in C6 cells, which remains visible in long echo time (T(E) = 136 ms) experiments, mostly originates from subcellular structures with diameters of 1-2 micro m, which correspond to the cytosolic lipid droplets that can be detected in optical microscopy preparations of the same cells.