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Eggert, D.

Publications and source records attributed to Eggert, D..

2 recordsLinked to original sources

Infrared Laser Sampling of Low Volumes Reveals Marker Lipids in Palatine Tonsil Carcinoma via Shotgun Lipidomics

Complete surgical resection is essential for oropharyngeal squamous cell carcinoma (OPSCC) therapy, underscoring the need for improved intraoperative margin assessment. To advance in-vivo diagnostics of OPSCC, Nanosecond infrared laser (NIRL) tissue sampling combined with shotgun lipidomic analysis reveals lipidome differences between OPSCC tissue and adjacent healthy tissue. Ablations were performed on tonsil squamous cell carcinoma on n=28 samples from 11 patients with an established chamber setup and a subset of n=6 samples from three patients with a custom-made handheld applicator. Welchs t-test results (p=0.05, two-fold change) revealed a similar OPSCC lipid profile in 7 of 11 patients. Potential tumor lipid markers were identified as consistently significantly increased, despite biological heterogeneity of the samples, underscoring their potential diagnostic value. Tissue ablation with a custom-made handheld applicator coupled to a laser fiber was successful and the lipidomic analysis was consistent to the chamber setup. Although our setup is currently limited by an ablation time exceeding one minute, this study demonstrates the potential of the handheld applicator for future applications such as endoscopy or intraoperative diagnostics.

cancer biology↗

Radial F-actin Organization During Early Neuronal Development

The centrosome is thought to be the major neuronal microtubule-organizing center (MTOC) in early neuronal development, producing microtubules with a radial organization. In addition, albeit in vitro, recent work showed that isolated centrosomes could serve as an actin-organizing center (Farina et al., 2016), raising the possibility that neuronal development may, in addition, require a centrosome-based actin radial organization. Here we report, using super-resolution microscopy and live-cell imaging, F-actin organization around the centrosome with dynamic F-actin aster-like structures with F-actin fibers extending and retracting actively. Photoconversion/photoactivation experiments and molecular manipulations of F-actin stability reveal a robust flux of somatic F-actin towards the cell periphery. Finally, we show that somatic F-actin intermingles with centrosomal PCM-1 satellites. Knockdown of PCM-1 and disruption of centrosomal activity not only affect F-actin dynamics near the centrosome but also in distal growth cones. Collectively the data show a radial F-actin organization during early neuronal development, which might be a cellular mechanism for providing peripheral regions with a fast and continuous source of actin polymers; hence sustaining initial neuronal development.

neuroscience↗