JITC Letter from the Editor - March 2019

Dear JITC Readers,

In the March edition of the JITC Digest, there are five important articles of which I would like to draw attention. First, the article “HDAC6 selective inhibition of melanoma patient T-cells augments anti-tumor characteristics,” by Andressa S. Laino et al. details the development of two HDAC6-selective inhibitors, ACY-1215 and ACY-241 as modulators of human T cell properties. Through ex vivo studies and at concentrations achievable in human patients, the reported HDAC6 inhibitors did considerably enhance melanoma patient T cell functions suggesting potential therapeutic efficacy.

Next, the research article, “Persistent mutant oncogene specific T cells in two patients benefitting from anti-PD-1,” by Kellie N. Smith et al. reports two cases of patients with biomarker-negative tumors (low mutational burden, negative for PD-L1, MMR proficient), each of which maintained a T cell response to a hotspot oncogenic mutation years after treatment initiation and both of whom derived durable clinical benefit from PD-1 blockade. Such results demonstrate that driver mutations may elicit efficient and durable anti-tumor immune responses and augment clinical response to immunotherapy.

Furthermore, the article, “Cancer-cell-secreted CXCL11 promoted CD8+ T cells infiltration through docetaxel-induced-release of HMGB1 in NSCLC,” by Qun Gao et al. presents novel data demonstrating the ability of docetaxel to upregulate CXCL11 in the tumor microenvironment through the release of HMGB1, subsequently driving the recruitment of CD8+ T cells and eliciting an improved immune response. This data supports the further development of clinical studies to measure anti-tumor immune response after docetaxel treatment in cancer patients.

“The IL-1/IL-1 receptor axis and tumor cell released inflammasome adaptor ASC are key regulators of TSLP secretion by cancer associated fibroblasts in pancreatic cancer,” by Emanuela Brunetto et al. identified tumor-derived IL-1-alpha and IL-1-beta as key cytokines in driving thymic stromal lymphopoietin (TLSP) secretion by cancer associated fibroblasts and tumor-released ASC. Results also demonstrate that treatment with an IL-1R antagonist significantly reduces TSLP expression in in vivo tumor models, providing support to the further assessment of therapies which aim to interfere with such pathways.

Finally, Cynthia Perez et al.’s article, “NKG2D signaling certifies effector CD8 T cells for memory formation,” shows that signaling through NKG2D in primary effector CD8 T cells is required for their differentiation into functional memory cells. As a better understanding of how long-term memory cells are formed from the initial effector pool of CD8 T cells remains an essential objective in immunology, this process of “memory certification” provides important clues to the development of improved vaccines and adoptive cellular therapies.

With best regards,

Pedro J. Romero, MD
Editor-in-Chief, Journal for ImmunoTherapy of Cancer

To view the entire March 2019 JITC Digest, please click here.