PI3K Isoform Immunotherapy for Solid Tumours

Improving the anti-tumour T cell response as a consequence of immunotherapy can result in eradication of tumour burden, however, the majority of patients fail with current treatment regimens and so novel immunotherapies with greater efficacy and improved tolerability are needed. The phosphoinositide-3-kinase (PI3K) family members that are directly involved in cell signalling comprise PI3Kα, PI3Kβ, PI3Kδ and PI3Kγ, with the latter two isoforms expressed primarily by leukocytes. The survival and optimal function of regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSCs) is dependent on PI3Kδ, whereas tumour-associated macrophages (TAMs), use PI3Kγ. Blocking these signalling isoforms can boost development of effective anti-cancer immune responses and result in control of tumour burden. The dependence on different PI3K isoforms in immune cells makes targeting this pathway an attractive approach for tumour immunotherapy. Herein, we discuss how inhibiting specific PI3K isoforms in pro-tumoural Tregs, MDSCS and TAMs can unleash a powerful anti-tumour immune response, driven by CD8+ T cells, capable of controlling tumour burden and consider how the immune response to therapy needs careful investigation, to identify both the correlates of successful treatment and those that impede the generation of robust anti-tumour responses. Furthermore, we review how combination immunotherapy approaches with both PI3K inhibitors and subsequent immune checkpoint blockade can potentiate the efficacy of monotherapy. Finally, we discuss the recent advances in the use of PI3K isoform-specific inhibitors as an immunotherapy for solid tumours in clinical trials.

Personalized Medicine: Recent Progress in Cancer Therapy

Translational research has revolutionized how we develop new treatments for cancer patients. The change from an organ-centric concept guiding treatment choice towards deep molecular analysis, driving a personalized approach, is one of the most important advances of modern oncology. Several tools such as next generation sequencing and RNA sequencing have greatly improved the capacity to detect predictive and prognostic molecular alterations. Detection of gene mutations, amplifications, and fusions has therefore altered the history of several diseases in both a localized and metastatic setting. This shift in perspective, in which attention is focused on the specific molecular alterations of the tumor, has opened the door to personalized treatment. This situation is reflected in the increasing number of basket trials selecting specific molecular targets. Nonetheless, some weaknesses need to be addressed. The complexity of cancer cells enriched with concomitant molecular alterations complicates identification of the driver. Moreover, tumor heterogeneity could be responsible for the lack of benefit when targeted agents are used. In light of this, there is growing interest in the role of multidisciplinary committees or molecular tumor boards to try to enhance selection. The aim of this review is to critically analyze the evolution of cancer treatment towards a precision approach, underlining some recent successes and unexpected failures.

Perspectives of Induction With Chemo and/or Immune Check Point Inhibition in Head and Neck Organ Preservation Treatment

Induction chemotherapy (ICT) is an attractive option for advanced head and neck squamous cell carcinoma (HNSCC) patients which has been prospectively evaluated in the context of a multimodality treatment approach. The theoretical benefit is the ability to suppress distant metastases and shrink the tumor while chemotherapy is better tolerated when given sequentially than concurrently. However, clinical trials have failed to show consistent benefit of ICT over concurrent radio-chemotherapy and due to so far lacking level 1 evidence ICT outside larynx organ preservation remains rather investigational. Immune modulation by inhibition of immune checkpoints is an exciting recent development in HNSCC which has mainly been investigated as second line treatment after progression on platinum-based chemotherapy in patients with recurrent/metastatic HNSCC. Due to the promising results in these trials and even more in the first-line trial KEYNOTE-048 and encouraging first preliminary results of preoperative Anti-PD1-application, the role of neoadjuvant immunotherapy is currently under investigation in HNSCC.

[Immunotherapy highlights of the ASCO annual meeting 2018 for head and neck cancers]

BACKGROUND

Immunotherapeutic strategies are becoming increasingly more important for head and neck cancer and numerous clinical trials were presented at the annual meeting of the American Society of Clinical Oncology (ASCO) 2018.

OBJECTIVE

In this review the most interesting clinical trials and trial results for immunotherapy of head and neck cancer are summarized.

MATERIAL AND METHODS

All abstracts and presentations on immunotherapy of head and neck cancer at the annual meeting of the ASCO 2018 were screened to select the most interesting trials for a more detailed analysis.

RESULTS

For head and neck cancer, practice changing phase III trial results were missing, but several noteworthy new strategies and trial results for immunotherapy were presented. Neoadjuvant immunotherapy trials, results concerning immunotherapy in old age, prognostic implications of immune-mediated adverse events and new immunotherapy combinations are summarized in this article.

CONCLUSION

The role of immunotherapy for the treatment of head and neck cancer is markedly increasing. Many pioneering trials are currently ongoing, in the phase of data analysis or in planning.