Abstract P5-07-13: Identification of a cancer stem sell-specific function for the histone deacetylases, HDAC1 and HDAC7, in breast and ovarian cancer

This abstract was withdrawn by the authors.

Blocking the regulatory T cell molecule LAG-3 augments in vivo anti-tumor immunity in an autochthonous model of prostate cancer

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Background: LAG-3 is a CD4 homolog expressed on activated T cells, NK cells, tumor infiltrating lymphocytes (TIL), and plasmacytoid dendritic cells. Recently, we showed that LAG-3 was relatively overexpressed in specific T cells rendered unresponsive in vivo by the presence of cognate self-antigen. These anergic T cells display regulatory function both in vitro and in vivo, and blockade of LAG-3 with a non-depleting monoclonal antibody significantly mitigates their regulatory T cell activity. Methods: Using a novel model of prostate cancer in which a tumor-specific antigen is expressed in autochthonous tumors, we tested whether treatment with a non-depleting anti-LAG-3 antibody affected trafficking and function of tumor-specific T cells. Results: LAG-3 blockade significantly augments specific CD8 T cell trafficking to antigen-expressing tumors, but not to normal tissue. Most significantly, LAG-3 blockade functionally reversed CD8 T cell tolerance as assayed by an in vivo cytotoxic T lymphocyte (CTL) assay. Combining LAG-3 blockade with specific anti-tumor vaccination results in a dramatic increase in activated CD8 T cells in the tumor parenchyma. Conclusions: Taken together, these data support the concept that treatment with a LAG-3 blocking antibody may significantly delay disease progression in patients with cancer. We have recently generated a panel of monoclonal antibodies directed against human LAG-3; several of these antibodies significantly augment human T cell responses in vitro.

No significant financial relationships to disclose.

Cocaine use and acute rupture of ectopic pregnancies

The hemodynamic changes associated with ingestion of cocaine may precipitate rupture of ectopic pregnancy. Two cases are presented in which this association was suspected. We believe this to be the first report of this clinical entity, representing a risk factor that should be identified in patients with suspected ectopic pregnancy.

The interaction of hemispheric preference, laterality, and sex in the perception of emotional tone and verbal content

Twenty male and 20 female subjects, divided into those who showed a right or left hemispheric preference, listened to auditory messages with conflicting verbal content and emotional tone. The messages were presented to each ear to determine whether the effect of hemisphere of input on the evaluation of the messages was modified by hemispheric preference. Except for left preference males, subjects responded on the basis of preference rather than laterality.