[Improvement of tissue fibrosis in TAFRO syndrome by prednisolone monotherapy].

We report the case of a 48-year-old man who presented with fatigue and weight loss. A local physician observed elevated alkaline phosphatase levels, anemia, thrombocytopenia, and renal dysfunction. Fever also appeared, and the patient was admitted to our hospital. Computed tomography revealed hepatosplenomegaly, pleural and ascitic fluid, and left axillary lymphadenopathy. Bone marrow biopsy indicated hyperplasia with increased megakaryocytes and reticulin fibrosis. Axillary lymph node biopsy showed Castleman's disease-like features. Liver biopsy revealed proliferation of reticulin fibrosis. Therefore, TAFRO syndrome was diagnosed and treatment with 1 mg/kg prednisolone was started. Anemia and thrombocytopenia improved, and after 24 weeks of treatment, serum hyaluronic acid and type IV collagen decreased to the normal range. Bone marrow biopsy after 18 weeks of treatment showed decreased reticular fibers. In TAFRO syndrome, improvement of liver and bone marrow fibrosis can be expected with adequate intervention, and serum hyaluronic acid and type IV collagen are useful for evaluating fibrosis.

[A Case of Immune-Related Adverse Events Affecting the Lungs, Skin, and Pituitary Gland during Pembrolizumab Treatment].

The patient was a 69-year-old man diagnosed with stage ⅣB lung adenocarcinoma with 95% programmed death- ligand 1 expression, and pembrolizumab monotherapy was initiated. The patient exhibited fatigue from the 12th course(36 weeks after treatment initiation) of treatment. Chest computed tomography revealed scattered ground-glass opacities in the upper lobes of both lungs, and he was subsequently diagnosed with interstitial pneumonia. Fatigue persisted even after a drug holiday from pembrolizumab, and the patient was diagnosed with hypopituitarism based on the results of endocrinological examinations. Rashes appeared on both legs 40 weeks after treatment initiation, which led to the patient being diagnosed with a drug-induced skin disorder. All the adverse events resolved upon treatment with hydrocortisone. Immune- related adverse events due to pembrolizumab may occur in multiple organs simultaneously.

Identification of EloA-BP1, a novel Elongin A binding protein with an exonuclease homology domain.

The Elongin complex stimulates the rate of transcription elongation by RNA polymerase II by suppressing the transient pausing of the polymerase at many sites along the DNA template. Elongin is composed of a transcriptionally active A subunit, and two positive regulatory B and C subunits. Although the NH(2)-terminal approximately 120 amino acid region of Elongin A is dispensable for its transcriptional activity in vitro, it shares significant sequence similarity with the NH(2)-terminus of other class of transcription factors SII and CRSP70, suggesting that the NH(2)-terminus mediates interactions important for the regulation of transcription in vivo. To identify proteins that can bind to these conserved sequences, a human B cell cDNA library was screened using the NH(2)-terminus of Elongin A as bait in a yeast two-hybrid system. Here, we report on the cloning and characterization of a novel human exonuclease domain-containing protein, Elongin A-binding protein 1 (EloA-BP1). EloA-BP1 is composed of 1221 amino acids and its mRNA is ubiquitously expressed. Double immunofluorescence labeling in COS7 cells suggested that EloA-BP1 and Elongin A are colocalized to the cell nucleus. By using an in vitro binding assay, we show that EloA-BP1 is capable of binding not only the NH(2)-terminal approximately 120 amino acid region of Elongin A, but also that of SII. Although the purified EloA-BP1 had no detectable effect on the rate of transcription elongation in vitro, it may play some role in the regulation of elongation in vivo.