Primary cutaneous lymphomas in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL): A series of 12 cases.

Background: Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is associated with an increased risk of a second malignancy.

Methods: We conducted a retrospective clinicopathologic review of 12 patients with CLL/SLL who developed a second lymphoma in the skin. Demographic data, clinical information, and histopathology from 31 biopsies were recorded.

ERK/MAPK Signaling Drives Overexpression of the Rac-GEF, PREX1, in BRAF- and NRAS-Mutant Melanoma.

Unlabelled: Recently, we identified that PREX1 overexpression is critical for metastatic but not tumorigenic growth in a mouse model of NRAS-driven melanoma. In addition, a PREX1 gene signature correlated with and was dependent on ERK MAPK activation in human melanoma cell lines. In the current study, the underlying mechanism of PREX1 overexpression in human melanoma was assessed.

P-Rex1 is required for efficient melanoblast migration and melanoma metastasis.

Metastases are the major cause of death from melanoma, a skin cancer that has the fastest rising incidence of any malignancy in the Western world. Molecular pathways that drive melanoblast migration in development are believed to underpin the movement and ultimately the metastasis of melanoma. Here we show that mice lacking P-Rex1, a Rac-specific Rho GTPase guanine nucleotide exchange factor, have a melanoblast migration defect during development evidenced by a white belly.

Infiltrative subcutaneous juvenile xanthogranuloma of the eyelid in a neonate.

An 18-day-old child presented with rapid enlargement of a firm subcutaneous eyelid mass present since birth. Imaging revealed extension into the anterior orbit. Incisional biopsy revealed juvenile xanthogranuloma.

Postsynaptic requirement for Abl kinases in assembly of the neuromuscular junction.

Agrin signals through the muscle-specific receptor tyrosine kinase (MuSK) to cluster acetylcholine receptors (AChRs) on the postsynaptic membrane of the neuromuscular junction (NMJ). This stands as the prevailing model of synapse induction by a presynaptic factor, yet the agrin-dependent MuSK signaling cascade is largely undefined. Abl1 (previously known as Abl) and the Abl1-related gene product Abl2 (previously known as Arg) define a family of tyrosine kinases that regulate actin structure and presynaptic axon guidance.