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Although effective, immune checkpoint blockade induces response in only a subset of cancer patients. There is an urgent need to discover new immune checkpoint targets. Recently, it was found that a class of sialic acid-binding immunoglobulin-like lectins (Siglecs) expressed on the surface of T cells in cancer patients inhibit T cell activation through their intracellular immunosuppressive motifs by recognizing sialic acid-carrying glycans, sialoglycans. However, ligands of Siglecs remain elusive. Here, we report sialylated IgG (SIA-IgG), a ligand to Siglec-7, that is highly expressed in epithelial cancer cells. SIA-IgG binds Siglec-7 directly and inhibits TCR signals. Blocking of either SIA-IgG or Siglec-7 elicited potent antitumor immunity in T cells. Our study suggests that blocking of Siglec-7/SIA-IgG offers an opportunity to enhance immune function while simultaneously sensitizing cancer cells to immune attack., (© 2022 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Total marrow irradiation (TMI) is an alternative to total body irradiation (TBI) as a component of the conditioning regimen for hematopoietic cell transplantation (HCT), offering the ability to deliver more targeted doses and facilitating organ-sparing. The organ-sparing effect of TMI is theorized to decrease the risk of complications associated with radiation, including subsequent malignant neoplasms (SMNs), while allowing for dosage escalation to improve oncologic outcomes. The purpose of this study was to compare SMNs rates among patients treated with TBI- or TMI-based conditioning regimens. We hypothesized that TMI would yield a rate of SMNs comparable to, if not lower than, TBI. A retrospective matched-pair analysis of patients who underwent allogeneic HCT and received either TBI- or TMI-based conditioning regimens to a total dose of 12 to 20 Gy was performed. A total of 171 patients received TMI-based conditioning and 171 received TBI-based conditioning, matched based on age, sex, diagnosis, and length of follow-up. SMNs were identified from an established long-term follow-up protocol, our institutional cancer registry, and the California Cancer Registry. There were no significant differences in patient and clinical characteristics between the TMI and TBI cohorts except for clinical response status at transplantation and radiation dose. As expected, patients in the TMI received higher radiation doses (median dose, 16.0 Gy for the TMI cohort versus 13.2 Gy for the TBI cohort; P < .001). The median follow-up for both cohorts was 2.0 years (range, .5 to 12.3 years). There was no significant difference in the risk of developing SMNs between the 2 cohorts (P = .81). A total of 9 patients (5.3%) conditioned with TBI and 10 patients (5.8%) conditioned with TMI developed SMNs, at a median of 3.3 years and 1.7 years following HCT, respectively. Excluding nonmelanoma skin cancers and noninvasive neoplasms, 2 patients in the TBI cohort developed SMNs (both melanomas), and 1 patient in the TMI cohort developed an SMN (colon cancer). No patients developed a subsequent hematologic malignancy. TMI-based conditioning is not associated with a significant difference in the risk of developing SMNs compared with TBI-based conditioning during early post-HCT follow-up. Future studies with longer follow-up may be needed to further characterize the risk of SMNs associated with TMI-based conditioning regimens compared with TBI-based regimens., (Copyright © 2022 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

The failure of T cells to eradicate tumour cells in the tumour microenvironment is mainly due to the dysfunction of T cells. Senescent T cells, with defects in proliferation and effector functions, accumulate in ageing, chronic viral infections, and autoimmune disorders where antigen stimulation persists. Increasing evidence suggests that inducing T cell senescence is a key strategy used by malignant tumours to evade immune surveillance. In this review, we summarize the general features, functional regulation, and signalling network of senescent T cells in tumour development and highlight their potential as prognostic biomarkers in multiple cancer treatments, including chemotherapy, radiotherapy, and immunotherapy. Moreover, we discuss possible therapeutic strategies for preventing or rejuvenating senescence in tumour-specific T cells. Understanding these critical issues may provide novel strategies to enhance cancer immunotherapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Previous studies have indicated coronavirus disease 2019 (COVID-19) patients with cancer have a high fatality rate., Methods: We conducted a systematic review of studies that reported fatalities in COVID-19 patients with cancer. A comprehensive meta-analysis that assessed the overall case fatality rate and associated risk factors was performed. Using individual patient data, univariate and multivariable logistic regression analyses were used to estimate odds ratios (OR) for each variable with outcomes., Results: We included 15 studies with 3019 patients, of which 1628 were men; 41.0% were from the United Kingdom and Europe, followed by the United States and Canada (35.7%), and Asia (China, 23.3%). The overall case fatality rate of COVID-19 patients with cancer measured 22.4% (95% confidence interval [CI] = 17.3% to 28.0%). Univariate analysis revealed age (OR = 3.57, 95% CI = 1.80 to 7.06), male sex (OR = 2.10, 95% CI = 1.07 to 4.13), and comorbidity (OR = 2.00, 95% CI = 1.04 to 3.85) were associated with increased risk of severe events (defined as the individuals being admitted to the intensive care unit, or requiring invasive ventilation, or death). In multivariable analysis, only age greater than 65 years (OR = 3.16, 95% CI = 1.45 to 6.88) and being male (OR = 2.29, 95% CI = 1.07 to 4.87) were associated with increased risk of severe events., Conclusions: Our analysis demonstrated that COVID-19 patients with cancer have a higher fatality rate compared with that of COVID-19 patients without cancer. Age and sex appear to be risk factors associated with a poorer prognosis., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)