Enhancement of anti-tumor efficacy of immune checkpoint blockade by alpha-TEA.

Cancer immunotherapy such as anti-PD-1/anti-PD-L1 immune checkpoint blockade (ICB) can provide significant clinical benefit in patients with advanced malignancies. However, most patients eventually develop progressive disease, thus necessitating additional therapeutic options. We have developed a novel agent, a-TEA-LS, that selectively induces tumor cell death while sparing healthy tissues, leading to increased activation of tumor-reactive T cells and tumor regression.

Reverting Immune Suppression to Enhance Cancer Immunotherapy.

Tumors employ strategies to escape immune control. The principle aim of most cancer immunotherapies is to restore effective immune surveillance. Among the different processes regulating immune escape, tumor microenvironment-associated soluble factors, and/or cell surface-bound molecules are mostly responsible for dysfunctional activity of tumor-specific CD8T cells.

Blockade of TGF-β signaling to enhance the antitumor response is accompanied by dysregulation of the functional activity of CD4CD25Foxp3 and CD4CD25Foxp3 T cells.

Background: The pleiotropic cytokine, transforming growth factor (TGF)-β, and CD4CD25Foxp3 regulatory T cells (Tregs) play a critical role in actively suppressing antitumor immune responses. Evidence shows that TGF-β produced by tumor cells promotes tolerance via expansion of Tregs. Our group previously demonstrated that blockade of TGF-β signaling with a small molecule TGF-β receptor I antagonist (SM16) inhibited primary and metastatic tumor growth in a T cell dependent fashion.

Mertk on tumor macrophages is a therapeutic target to prevent tumor recurrence following radiation therapy.

Radiation therapy provides a means to kill large numbers of cancer cells in a controlled location resulting in the release of tumor-specific antigens and endogenous adjuvants. However, by activating pathways involved in apoptotic cell recognition and phagocytosis, irradiated cancer cells engender suppressive phenotypes in macrophages. We demonstrate that the macrophage-specific phagocytic receptor, Mertk is upregulated in macrophages in the tumor following radiation therapy.

GMP-grade α-TEA lysine salt: a 28-Day oral toxicity and toxicokinetic study with a 28-Day recovery period in Beagle dogs.

Background: Alpha-tocopheryloxyacetic acid (α-TEA) is a semi-synthetic derivative of naturally occurring vitamin E (alpha-tocopherol) that can be delivered via an oral route. Preclinical in vitro and in vivo data demonstrated that α-TEA is a potent anti-tumor agent with a safe toxicity profile in mice. We report a comprehensive study to evaluate the toxokinetics of good manufacturing practice (GMP)-grade α-TEA in dogs after daily oral administration for 28 days, followed by a 28-day recovery period.