Germline mutations of SMARCA4 in small cell carcinoma of the ovary, hypercalcemic type and in SMARCA4-deficient undifferentiated uterine sarcoma: Clinical features of a single family and comparison of large cohorts.

OBJECTIVE: Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) and SMARCA4-deficient undifferentiated uterine sarcoma (SMARCA4-DUS) are rare and aggressive tumors, primarily affecting pre- and perimenopausal women. Inactivating SMARCA4 mutations are thought to be the driving molecular events in the majority of these tumors. Here, we report the clinical course of a family with germline SMARCA4 mutation and compare large cohorts of these rare tumor types. METHODS: We extracted clinico-pathological medical record data for the family with germline SMARCA4 mutation. Clinico-genomic data from SCCOHT and SMARCA4-DUS cohorts were retrospectively extracted from the archives of a large CLIA-certified reference molecular laboratory. RESULTS: We identified a single family with an inherited germline SMARCA4 mutation, in which two different family members developed either SCCOHT or SMARCA4-DUS, both of whom died within one year of diagnosis, despite aggressive surgical, chemotherapy and immunotherapy treatment. Retrospective comparative analysis of large SCCOHT (n = 48) and SMARCA4-DUS (n = 17) cohorts revealed that SCCOHT patients were younger (median age: 28.5 vs. 49.0) and more likely to have germline SMARCA4 alterations (37.5% vs. 11.8%) than SMARCA4-DUS patients. CONCLUSIONS: Growing understanding of the role SMARCA4 plays in the pathogenesis of these rare cancers may inform recommended genetic testing and counseling in families with these tumor types.

Prioritizing Patient Safety and Minimizing Waste: Institutional Review of Cases and a Proposed Process for Designing a Surgical Pathology Gross-Only Examination Policy.

OBJECTIVES: Gross-only examination policies vary widely across pathology departments. Several studies-particularly a College of American Pathologists' Q-Probes study-have looked at the variations in gross-only policies, and even more studies have addressed the (in)appropriateness of certain specimen types for gross-only examination. Few, if any, studies have tackled the important task of how to revise and safely implement a new gross-only examination protocol, especially in collaboration with clinical colleagues. METHODS: We reviewed the grossing protocols from three anatomic pathology centers to identify common gross-only specimen types. We compiled an inclusive list of any specimen types that appeared on one or more centers' lists. We performed a retrospective review of the gross and microscopic diagnoses for those specimen types to determine if any diagnoses of significance would have been missed had that specimen been processed as a gross-only. RESULTS: We reviewed 940 cases among 13 specimen types. For 7 specimen types, the gross diagnoses provided equivalent information to the microscopic diagnoses. For 6 specimen types, microscopic diagnoses provided clinically meaningful information beyond what was captured in the gross diagnoses. CONCLUSIONS: To improve the value of care provided, pathology departments should conduct internal reviews and consider transitioning specimen types to gross-only when safe.

Acute lymphoblastic leukemia with 4;11 translocation analyzed by a multi-modal strategy of conventional cytogenetics, FISH, morphology, flow cytometry and molecular genetics, and review of the literature.

We report a case of acute lymphoblastic leukemia (ALL) with a 4;11 translocation. Metaphase cells and interphase nuclei derived from a routine unstimulated culture of bone marrow were analyzed using a combined strategy of G-banding and fluorescent in situ hybridization (FISH) in addition to hematopathological analysis, flow cytometry, and molecular genetics. This multimodal approach enables a successful correlation of pathology and cytogenetics to support a comprehensive diagnosis of the patient. Meaningful prognostication and appropriate therapeutic considerations are possible only when accurate diagnostic information is given. We further search and review the literature for the most up-to-date information currently available for this subtype of ALL in the constantly evolving field of molecular cytogenetics.

MEK inhibition and phosphorylation of serine 4 on B23 are two coincident events in mitosis.

Previous studies have shown that activation of the Raf/MEK/ERK pathway is necessary for G2/M transition. However, as for the activation state of MEK in mitosis the conclusion is not consistent. Here we show that MEK is inhibited in mitosis. In addition, we identify a multifunctional protein named B23 that strongly cross-reacts with a phospho-MEK antibody in mitotic cells. Sequence homology between the N-terminus surrounding Ser 4 of B23 and the Raf phosphorylation site on MEK suggests a mechanism for cross-reaction of the antibody. Thus, mutation of Ser 4 to alanine abolishes cross-reactivity between B23 and the phospho-MEK antibody. Our findings may explain the discrepancy of results obtained with the use of phospho-MEK antibody regarding the activation state of MEK in mitosis.

Interaction between active Pak1 and Raf-1 is necessary for phosphorylation and activation of Raf-1.

Activation of Raf-1 is a complex process in which phosphorylation of Ser(338)-Tyr(341) is a critical step. Previous studies have shown that Pak1/2 is implicated in both Ras-dependent and -independent activation of Raf-1 by phosphorylating Raf Ser(338). The present study explores the structural basis of Raf-1 phosphorylation by Pak1. We found that Pak directly associates with Raf-1 under both physiological and overexpressed conditions. The association is greatly stimulated by 4beta-12-O-tetradecanoylphorbol-13-acetate and nocodazole and by expression of the active mutants of Rac and Ras. The active forms of Pak generated by mutation of Thr(423) to Glu or truncation of the amino-terminal moiety exhibit a greater binding to Raf than the wild type, whereas the kinase-dead mutant Pak barely binds Raf. The extent of binding to Raf-1 is correlated with the ability of Pak to phosphorylate Raf and induce mitogen-activated protein kinase activation. Furthermore, the Raf-1 binding site is defined to the carboxyl terminus of the Pak catalytic domain. In addition, our results suggest that the amino-terminal regulatory region of Raf inhibits the interaction. Taken together, the results indicate that the interaction depends on the active conformations of Pak and Raf. They also argue that Pak1 is a physiological candidate for phosphorylation of Raf Ser(338) during the course of Raf activation.