Immunotherapy for esophageal cancer:Where are we now and where can we go

Immune checkpoint inhibitor therapy has dramatically improved patient prognosis,and thereby transformed the treatment in various cancer types including esophageal squamous cell carcinoma(ESCC)in the past decade.Monoclonal antibodies that selectively inhibit programmed cell death-1(PD-1)activity has now become standard of care in the treatment of ESCC in metastatic settings,and has a high expectation to provide clinical benefit during perioperative period.Further,anti-cytotoxic T-lymphocyte–associated protein 4(CTLA-4)monoclonal antibody has also been approved in the treatment of recurrent/metastatic ESCC in combination with anti-PD-1 antibody.Well understanding of the existing evidence of immune-based treatments for ESCC,as well as recent clinical trials on various combinations with chemotherapy for different clinical settings including neoadjuvant,adjuvant,and metastatic diseases,may provide future prospects of ESCC treatment for better patient outcomes.

Viro-immune therapy:A new strategy for treatment ofpancreatic cancer

Pancreatic ductal adenocarcinoma(PDAC) is an almost uniformly lethal disease with less than 5% survival at five years. This is largely due to metastatic disease, which is already present in the majority of patients when diagnosed. Even when the primary cancer can be removed by radical surgery, local recurrence occurs within one year in 50%-80% of cases. Therefore, it is imperative to develop new approaches for the treatment of advanced cancer and the prevention of recurrence after surgery. Tumour-targeted oncolytic viruses(TOVs) have become an attractive therapeutic agent as TOVs can kill cancer cells through multiple mechanisms of action, especially via virus-induced engagement of the immune response specifically against tumour cells. To attack tumour cells effectively, tumour-specific T cells need to overcome negative regulatory signals that suppress their activation or that induce tolerance programmes such as anergy or exhaustion in the tumour microenvironment. In this regard, the recent breakthrough in immunotherapy achieved with immune checkpoint blockade agents, such as anti-cytotoxic T-lymphocyte-associate protein 4, programmed death 1(PD-1) or PD-L1 antibodies, has demonstrated the possibility of relieving immune suppression in PDAC. Therefore, the combination of oncolytic virotherapy and immune checkpoint blockade agents may synergistically function to enhance the antitumour response, lending the opportunity to be the future for treatment of pancreatic cancer.

Immunotherapy in pancreatic cancer:Unleash its potential through novel combinations

Pancreatic cancer is the third leading cause of cancer mortality in both men and women in the United States,with poor response to current standard of care,short progression-free and overall survival.Immunotherapies that target cytotoxic T lymphocyte antigen-4,programmed cell death protein-1,and programmed death-ligand 1 checkpoints have shown remarkable activities in several cancers such as melanoma,renal cell carcinoma,and nonsmall cell lung cancer due to high numbers of somatic mutations,combined with cytotoxic T-cell responses.However,single checkpoint blockade was ineffective in pancreatic cancer,highlighting the challenges including the poor antigenicity,a dense desmoplastic stroma,and a largely immunosuppressive microenvironment.In this review,we will summarize available clinical results and ongoing efforts of combining immune checkpoint therapies with other treatment modalities such as chemotherapy,radiotherapy,and targeted therapy.These combination therapies hold promise in unleashing the potential of immunotherapy in pancreatic cancer to achieve better and more durable clinical responses by enhancing cytotoxic T-cell responses.