No abstract

Semaphorins are a large family of molecules involved in axonal guidance during the development of the nervous system and have been recently shown to have both angiogenic and anti-angiogenic properties. Specifically, semaphorin 7A (SEMA7A) has been reported to have a chemotactic activity in neurogenesis and to be an immune modulator through α1β1integrins. SEMA7A has been shown to promote monocyte chemotaxis and induce them to produce proinflammatory mediators. In this study we explored the role of SEMA7A in a murine model of breast cancer. We show that SEMA7A is highly expressed by DA-3 murine mammary tumor cells in comparison to normal mammary cells (EpH4), and that peritoneal elicited macrophages from mammary tumor-bearing mice also express SEMA7A at higher levels compared to those derived from normal mice. We also show that murine macrophages treated with recombinant murine SEMA7A significantly increased their expression of proangiogenic molecule CXCL2/MIP-2. Gene silencing of SEMA7A in peritoneal elicited macrophages from DA-3 tumor-bearing mice resulted in decreased CXCL2/MIP-2 expression. Mice implanted with SEMA7A silenced tumor cells showed decreased angiogenesis in the tumors compared to the wild type tumors. Furthermore, peritoneal elicited macrophages from mice bearing SEMA7A-silenced tumors produce significantly (p < 0.01) lower levels of angiogenic proteins, such as CXCL2/MIP-2, CXCL1, and MMP-9, compared to those from control DA-3 mammary tumors. We postulate that SEMA7A in mammary carcinomas may skew monocytes into a pro-tumorigenic phenotype to support tumor growth. SEMA7A could prove to be valuable in establishing new research avenues toward unraveling important tumor-host immune interactions in breast cancer patients.

The classification of MFH has been recently debated. Nevertheless, our case is the second report of pediatric MFH involving the parotid gland. Surgical resection is the preferred treatment, but combined chemoradiation may be necessary in the head and neck region.

Herpes simplex virus (HSV) is regarded as a common viral pathogen that produces a wide variety of diseases. After a primary infection, which usually occurs during childhood and may or may not be clinically evident, the virus establishes a latent infection in the local sensory ganglia and can reactivate throughout the life of the individual. Fulminant hepatic failure (FHF) due to HSV infection is a clinical condition well known in pediatric, immunocompromised, and pregnant patients. It is rare in immunocompetent hosts. We report the case of a 51-year-old man with no significant past medical history who developed FHF with disseminated intravascular coagulopathy and septic shock secondary to HSV infection. The initial diagnosis was made through a frozen section of a needle liver biopsy and the presence of HSV was confirmed in the permanent section with immunohistochemistry. HSV was grown in cell culture from liver tissue obtained through an autopsy.

We have characterized the lymphocytes in the synovium of patients with rheumatoid arthritis (RA) by immunohistochemistry using monoclonal antibodies directed against B lymphocytes, T lymphocytes, and antibodies directed against CD45RA and CD45RO, which define T-cell subsets. Both CD45RA+ and CD45RO+ T lymphocytes were detected in the perivascular regions. CD45RA+ lymphocytes were present primarily in perivascular areas of moderate to large lymphocytic infiltration. Some synovial perivascular lymphocytic aggregates were organized into focal areas of CD45RA+ B lymphocytes surrounded by CD45RO+ T lymphocytes. In areas of diffuse lymphocytic infiltration, the T lymphocytes were CD45RO+. These data suggest that both CD45RO+ and CD45RA+ T lymphocytes enter the RA synovial tissue via the synovial vasculature and that, once in the tissue, the CD45RA+ T lymphocytes may undergo activation/maturation and acquire the CD45RO phenotype.

Metastasis is the primary cause of mortality in women with breast cancer. Metastasis to the lungs is greater in patients with pulmonary inflammatory illnesses. It is unknown how pre-existing pulmonary inflammation affects mammary tumor progression. We developed a novel breast cancer model in which pulmonary inflammation is induced in mice prior to tumor cell implantation. In the present study, we determined how pre-existing allergen-induced inflammation changes the pulmonary microenvironment to exacerbate tumor metastasis. We showed that pre-existing pulmonary inflammation in mammary tumor bearers is associated with: 1) an increase in growth of the primary tumor and metastasis; 2) an increase in the expression of a glycoprotein known as CHI3L1; and 3) increase in the levels of myeloid populations in their lungs. We also showed that myeloid derived cells from the lungs of allergic tumor bearers produce higher amounts of CHI3L1 than the saline controls. We previously showed that CHI3L1 induces the expression of proinflammatory and protumorigenic molecules. In this study, we show that CHI3L1 knockout tumor bearers with pre-existing allergic pulmonary inflammation had decreased levels of myeloid-derived cells, decreased levels of proinflammatory mediators, and a significant reduction in tumor volume and metastasis compared with the wild-type controls. Pre-existing inflammation and CHI3L1 might be driving the establishment of a premetastatic milieu in the lungs and aiding in the support of metastatic foci. Understanding the role of allergen-induced CHI3L1 and inflammation in tumor bearers and its effects on the pulmonary microenvironment could result in targeted therapies for breast cancer.

A pulmonary meningioma was removed from a 55-year-old woman. She had no evidence of a cranial meningioma after a 3-year follow-up period. Results of immunohistochemical and electron microscopic studies of the tumor were similar to those for cranial meningiomas. The literature on this subject was reviewed and a possible origin for these tumors in the lung is discussed.

Rosai-Dorfman disease is a rare clinical disorder which may present in many forms. While classically a disease of lymph nodes, soft tissue involvement is fairly common. Soft tissue involvement can occur without any lymphatic or systemic involvement, and may be difficult to diagnose. We describe a patient presenting with multiple soft tissue masses which on biopsy proved to be isolated cutaneous Rosai-Dorfman disease. MR imaging showed two well-defined nonspecific superficial masses that enhanced intensely. Review of the literature suggests that when this disease presents in soft tissue, multiple foci of involvement may be common. Although rare, Rosai-Dorfman disease should be considered in the differential diagnosis of patients presenting with multiple soft tissue masses.