Trifluridine/tipiracil plus bevacizumab in patients with untreated metastatic colorectal cancer ineligible for intensive therapy: the randomized TASCO1 study.

BACKGROUND: We designed an open-label, noncomparative phase II study to assess the safety and efficacy of first-line treatment with trifluridine/tipiracil plus bevacizumab (TT-B) and capecitabine plus bevacizumab (C-B) in untreated patients with unresectable metastatic colorectal cancer (mCRC) who were not candidates for combination with cytotoxic chemotherapies. PATIENTS AND METHODS: From 29 April 2016 to 29 March 2017, 153 patients were randomly assigned (1:1) to either TT-B (N = 77) or C-B (N = 76). The primary end point was progression-free survival (PFS). The primary PFS analysis was performed after 100 events (radiological progression or death) were observed. Secondary end points included overall survival (OS), quality of life (QoL; QLQ-C30 and QLQ-CR29 questionnaires), and safety. RESULTS: Median (range) duration of treatment was 7.8 (6.0-9.7) months and 6.2 (4.1-9.1) months in the TT-B and C-B groups, respectively. Median (range) PFS was 9.2 (7.6-11.6) and 7.8 (5.5-10.1) months, respectively. Median (range) OS was 18 (15.2 to NA) and 16.2 (12.5 to NA) months, respectively. QoL questionnaires showed no relevant changes over time for either treatment. Therapies were well tolerated. Patients receiving TT-B had more grade ≥3 neutropenia (47% versus 5% with C-B). Patients receiving C-B had more grade ≥3 hand-foot syndrome (12% versus 0% with TT-B) and grade ≥3 diarrhea (8% versus 1% with TT-B), consistent with the known safety profiles of these agents. CONCLUSION: TT-B treatment showed promising clinical activity in untreated patients with unresectable mCRC ineligible for intensive therapy, with an acceptable safety profile and no clinically relevant changes in QoL. CLINICAL TRIAL INFORMATION: NCT02743221 (ClinicalTrials.gov).

Autophagy inhibition radiosensitizes in vitro, yet reduces radioresponses in vivo due to deficient immunogenic signalling.

Clinical oncology heavily relies on the use of radiotherapy, which often leads to merely transient responses that are followed by local or distant relapse. The molecular mechanisms explaining radioresistance are largely elusive. Here, we identified a dual role of autophagy in the response of cancer cells to ionizing radiation. On one hand, we observed that the depletion of essential autophagy-relevant gene products, such as ATG5 and Beclin 1, increased the sensitivity of human or mouse cancer cell lines to irradiation, both in vitro (where autophagy inhibition increased radiation-induced cell death and decreased clonogenic survival) and in vivo, after transplantation of the cell lines into immunodeficient mice (where autophagy inhibition potentiated the tumour growth-inhibitory effect of radiotherapy). On the other hand, when tumour proficient or deficient for autophagy were implanted in immunocompetent mice, it turned out that defective autophagy reduced the efficacy of radiotherapy. Indeed, radiotherapy elicited an anti-cancer immune response that was dependent on autophagy-induced ATP release from stressed or dying tumour cells and was characterized by dense lymphocyte infiltration of the tumour bed. Intratumoural injection of an ecto-ATPase inhibitor restored the immune infiltration of autophagy-deficient tumours post radiotherapy and improved the growth-inhibitory effect of ionizing irradiation. Altogether, our results reveal that beyond its cytoprotective function, autophagy confers immunogenic properties to tumours, hence amplifying the efficacy of radiotherapy in an immunocompetent context. This has far-reaching implications for the development of pharmacological radiosensitizers.