Faculty Bibliography

Across the world, there are varied cultural practices applied in the newborn period that pediatric dermatologists need to be familiar with. This report details a 9-day-old girl who presented with black, spike-like hairs across the back after her mother had been rubbing breast milk on her back in a circular motion for the first 7 days of life. On dermatoscopic exam, these lesions were found to be tight bundles of lanugo hairs, consistent with a diagnosis of knotted lanugo. Improved understanding of cultural practices and newborn skin care routines is critical for diagnosis, treatment, and counseling.

The SLC7A11/xCT cystine and glutamate antiporter has emerged as an attractive target for cancer therapy due to its selective overexpression in multiple cancers and its role in preventing ferroptosis. Utilizing pharmacological and genetic approaches in hepatocellular carcinoma cell lines, we demonstrate that overexpression of SLC7A11 engenders hypersensitivity towards l-selenocystine, a naturally occurring diselenide that bears close structural similarity to l-cystine. We find that the abundance of SLC7A11 positively correlates with sensitivity to l-selenocystine, but surprisingly, not to Erastin, an inhibitor of SLC7A11 activity. Our data indicate that SLC7A11 acts as a transport channel for l-selenocystine, which preferentially incites acute oxidative stress and damage eventuating to cell death in cells that highly express SLC7A11. Hence, our findings raise the prospect of l-selenocystine administration as a novel strategy for targeting cancers that up-regulate SLC7A11 expression.