Mitochondria in epithelial ovarian carcinoma exhibit abnormal phenotypes and blunted associations with biobehavioral factors

Malignant tumor cells exhibit mitochondrial alterations and are also influenced by biobehavioral processes, but the intersection of biobehavioral factors and mitochondria in malignant tumors remains unexplored. Here we examined multiple biochemical and molecular markers of mitochondrial content and function in benign tissue and in high-grade epithelial ovarian carcinoma (EOC) in parallel with exploratory analyses of biobehavioral factors. First, analysis of a publicly-available database (n = 1435) showed that gene expression of specific mitochondrial proteins in EOC is associated with survival. Quantifying multiple biochemical and molecular markers of mitochondrial content and function in tissue from 51 patients with benign ovarian masses and 128 patients with high-grade EOC revealed that compared to benign tissue, EOCs exhibit 3.3–8.4-fold higher mitochondrial content and respiratory chain enzymatic activities (P < 0.001) but similar mitochondrial DNA (mtDNA) levels (− 3.1%), documenting abnormal mitochondrial phenotypes in EOC. Mitochondrial respiratory chain activity was also associated with interleukin-6 (IL-6) levels in ascites. In benign tissue, negative biobehavioral factors were inversely correlated with mitochondrial content and respiratory chain activities, whereas positive biobehavioral factors tended to be positively correlated with mitochondrial measures, although effect sizes were small to medium (r = − 0.43 to 0.47). In contrast, serous EOCs showed less pronounced biobehavioral-mitochondrial correlations. These results document abnormal mitochondrial functional phenotypes in EOC and warrant further research on the link between biobehavioral factors and mitochondria in cancer

Dual Anti-OX40/IL-2 Therapy Augments Tumor Immunotherapy via IL-2R-Mediated Regulation of OX40 Expression

The provision of T cell co-stimulation via members of the TNFR super-family, including OX40 (CD134) and 4-1BB (CD137), provides critical signals that promote T cell survival and differentiation. Recent studies have demonstrated that ligation of OX40 can augment T cell-mediated anti-tumor immunity in pre-clinical models and more importantly, OX40 agonists are under clinical development for cancer immunotherapy. OX40 is of particular interest as a therapeutic target as it is not expressed on naïve T cells but rather, is transiently up-regulated following TCR stimulation. Although TCR engagement is necessary for inducing OX40 expression, the downstream signals that regulate OX40 itself remain unclear. In this study, we demonstrate that OX40 expression is regulated through a TCR and common gamma chain cytokine-dependent signaling cascade that requires JAK3-mediated activation of the downstream transcription factors STAT3 and STAT5. Furthermore, combined treatment with an agonist anti-OX40 mAb and IL-2 augmented tumor immunotherapy against multiple tumor types. Dual therapy was also able to restore the function of anergic tumor-reactive CD8 T cells in mice with long-term well-established (>5 wks) tumors, leading to increased survival of the tumor-bearing hosts. Together, these data reveal the ability of TCR/common gamma chain cytokine signaling to regulate OX40 expression and demonstrate a novel means of augmenting cancer immunotherapy by providing dual anti-OX40/common gamma chain cytokine-directed therapy

Sequencing three crocodilian genomes to illuminate the evolution of archosaurs and amniotes

The International Crocodilian Genomes Working Group (ICGWG) will sequence and assemble the American alligator (Alligator mississippiensis), saltwater crocodile (Crocodylus porosus) and Indian gharial (Gavialis gangeticus) genomes. The status of these projects and our planned analyses are described

Immune Checkpoint Blockade in Gastrointestinal Cancers: The Current Status and Emerging Paradigms

Immunotherapy is a rapidly evolving treatment paradigm that holds promise to provide long-lasting survival benefits for patients with cancer. This promise, however, remains unfulfilled for the majority of patients with gastrointestinal (GI) cancers, as significant limitations in efficacy exist with immune checkpoint inhibitors (ICIs) in this disease group. A plethora of novel combination treatment strategies are currently being investigated in various clinical trials to make them more efficacious as our understanding of molecular mechanisms mediating resistance to immunotherapy advances. In this article, we summarize the current status of immune checkpoint blockade in GI cancers and discuss the biological rationales that underlie the emerging treatment strategies being tested in ongoing clinical trials in combination with ICIs. We also highlight the promising early results from these strategies and provide future perspectives on enhancing response to immunotherapy for patients with GI cancers

STAT3 and STAT5 are required for optimal up-regulation of OX40 following stimulation with common gc cytokines.

<p><b>A</b>) WT or STAT3^−/− OT-I T cells were stimulated for 2 days, harvested, and then re-cultured with media alone, rmIL-2, rmIL-4, or rmIL-21 (100 ng/ml); 24 hours later cells were harvested and the extent of CD25 and OX40 expression (% positive and MFI) were measured. <b>B</b>) Polyclonal endogenous WT or STAT5^−/− CD8 T cells were stimulated for 2 days with 2 mcg/ml anti-CD3 mAb, harvested, and then re-cultured with media alone, rmIL-2, rmIL-4, or rmIL-21 (100 ng/ml) and then 24 hours later, cells were harvested and the extent of CD25 and OX40 expression (% positive and MFI) were determined. <b>A, B</b>) Bar graphs depict the mean+/−SD (n = 2–3/group). Data are representative of one out of two independent experiments. *P<0.05; ** P<0.01; *** P<0.001; NS = no statistically significant difference.</p

OX40 is regulated on murine and human T cells by TCR stimulation and IL-2.

<p><b>A</b>) Purified naïve wild-type or OX40^−/− OT-I T cells (1×10⁶/ml) were stimulated with peptide-pulsed APCs (6×10⁶/ml). Two days later, OT-I T cells were harvested and re-cultured (5×10⁵ cells/ml) +/− rmIL-2 (100 ng/ml). Twenty-four hours later, cells were harvested and the extent of CD25 and OX40 expression were determined. Bar graphs depict the mean+/−SEM (n = 6/group). <b>B, C</b>) Human CD8 or <b>C</b>) CD4 T cells collected from PBMC were stimulated with media, rhIL-2 (5,000 IU/ml, equivalent to 300 ng/ml), and/or 1 mcg/ml anti-CD3 mAb (OKT-3). Forty-eight hours later, cells were harvested, washed, and stimulated with media or rhIL-2 (5,000 IU/ml). Twenty-four hours later, the extent of CD25 and OX40 expression were measured. <b>C</b>) Bar graphs depict the mean+/−SD (n = 3–5/group). Data are pooled from five independent experiments. *P<0.05; **P<0.01; ***P<0.001.</p