The SH3-SAM adaptor HACS1 is up-regulated in B cell activation signaling cascades

HACS1 is a Src homology 3 and sterile alpha motif domain-containing adaptor that is preferentially expressed in normal hematopoietic tissues and malignancies including myeloid leukemia, lymphoma, and myeloma. Microarray data showed HACS1 expression is up-regulated in activated human B cells treated with interleukin (IL)-4, CD40L, and anti-immunoglobulin (Ig)M and clustered with genes involved in signaling, including TNF receptor-associated protein 1, signaling lymphocytic activation molecule, IL-6, and DEC205. Immunoblot analysis demonstrated that HACS1 is up-regulated by IL-4, IL-13, anti-IgM, and anti-CD40 in human peripheral blood B cells. In murine spleen B cells, Hacs1 can also be up-regulated by lipopolysaccharide but not IL-13. Induction of Hacs1 by IL-4 is dependent on Stat6 signaling and can also be impaired by inhibitors of phosphatidylinositol 3-kinase, protein kinase C, and nuclear factor kappaB. HACS1 associates with tyrosine-phosphorylated proteins after B cell activation and binds in vitro to the inhibitory molecule paired Ig-like receptor B. Overexpression of HACS1 in murine spleen B cells resulted in a down-regulation of the activation marker CD23 and enhancement of CD138 expression, IgM secretion, and Xbp-1 expression. Knock down of HACS1 in a human B lymphoma cell line by small interfering ribonucleic acid did not significantly change IL-4-stimulated B cell proliferation. Our study demonstrates that HACS1 is up-regulated by B cell activation signals and is a participant in B cell activation and differentiation.     

Müllerian adenosarcoma of vagina arising in persistent endometriosis: report of a case and review of the literature

BACKGROUND: Primary adenosarcoma arising in vaginal endometriosis poses a diagnostic challenge, especially in superficial vaginal biopsies. CASE: A 56-year-old woman, with a prior diagnosis of ovarian endometriosis, presented with a rapidly enlarging mass of the vaginal vault. Two prior biopsies were benign and showed endometriosis. The third vaginal biopsy revealed benign endometriotic glands cuffed by a cellular stroma with moderate cytologic atypia, a histological appearance diagnostic of Müllerian adenosarcoma. A 16-cm vaginal mass that had infiltrated the pelvic structures was resected. CONCLUSIONS: Close clinical follow-up of extrauterine endometriosis and clinical-pathologic correlation is necessary. Histological features such as cellular stromal cuffing around benign endometriotic glands are critical in arriving at a timely diagnosis of adenosarcoma in patients with persistent extrauterine endometriosis, even in superficial vaginal biopsies.     

Long-term effects of polymer-based, slow-release, sirolimus-eluting stents in a porcine coronary model

BACKGROUND: Stent-based delivery of sirolimus (SRL) has shown reduction in neointimal hyperplasia and restenosis. The purpose of this study was to evaluate the chronic vascular response and the expression of cell cycle regulators after SRL-eluting stent implantation in a porcine coronary model. METHODS: Forty-nine pigs underwent placement of 109 oversized stents (control, n=54, SRL (140 microg/cm(2)), n=55) in the coronary arteries with histologic analysis and Western blot (PCNA, p27(kip1), CD45, MCP-1, IL-2, IL-6, TNF-beta) at 3, 30, 90 or 180 days. RESULTS: At 3 days, the mean thrombus area was similar for control (0.38+/-0.19 mm(2)) and SRL (0.29+/-0.09 mm(2)) stents. After 30 days, the mean neointimal area was significantly less for the SRL (1.40+/-0.35 mm(2)) versus the control stents (2.94+/-1.28 mm(2), p<0.001). At 90 and 180 days, the mean neointimal area was similar for the SRL (3.03+/-0.92 and 3.34+/-0.99 mm(2)) as compared with control stents (3.45+/-1.09 and 3.65+/-1.23 mm(2)). Western blot analysis demonstrated an increased expression of p27(kip1) in the vessel wall at 90 days for the SRL versus control stents (p=0.05) but with increased levels of PCNA in the SRL as compared with control stents (p=0.003). CONCLUSION: SRL-eluting stents favorably modulate neointimal formation for 30 days in the porcine coronary model. Long-term inhibition of neointimal hyperplasia is not sustained presumably due to delayed cellular proliferation despite increased levels of the cyclin-dependent kinase p27(kip1) in the vessel wall.