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Emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants diminishes the efficacy of vaccines and antiviral monoclonal antibodies. Continued development of immunotherapies and vaccine immunogens resilient to viral evolution is therefore necessary. Using coldspot-guided antibody discovery, a screening approach that focuses on portions of the virus spike glycoprotein that are both functionally relevant and averse to change, we identified human neutralizing antibodies to highly conserved viral epitopes. Antibody fp.006 binds the fusion peptide and cross-reacts against coronaviruses of the four genera, including the nine human coronaviruses, through recognition of a conserved motif that includes the S2′ site of proteolytic cleavage. Antibody hr2.016 targets the stem helix and neutralizes SARS-CoV-2 variants. Antibody sd1.040 binds to subdomain 1, synergizes with antibody rbd.042 for neutralization, and, similar to fp.006 and hr2.016, protects mice expressing human angiotensin-converting enzyme 2 against infection when present as a bispecific antibody. Thus, coldspot-guided antibody discovery reveals donor-derived neutralizing antibodies that are cross-reactive with Orthocoronavirinae, including SARS-CoV-2 variants.

Currently circulating SARS-CoV-2 variants acquired convergent mutations at receptor-binding domain (RBD) hot spots1. Their impact on viral infection, transmission, and efficacy of vaccines and therapeutics remains poorly understood. Here, we demonstrate that recently emerged BQ.1.1. and XBB.1 variants bind ACE2 with high affinity and promote membrane fusion more efficiently than earlier Omicron variants. Structures of the BQ.1.1 and XBB.1 RBDs bound to human ACE2 and S309 Fab (sotrovimab parent) explain the altered ACE2 recognition and preserved antibody binding through conformational selection. We show that sotrovimab binds avidly to all Omicron variants, promotes Fc-dependent effector functions and protects mice challenged with BQ.1.1, the variant displaying the greatest loss of neutralization. Moreover, in several donors vaccine-elicited plasma antibodies cross-react with and trigger effector functions against Omicron variants despite reduced neutralizing activity. Cross-reactive RBD-directed human memory B cells remained dominant even after two exposures to Omicron spikes, underscoring persistent immune imprinting. Our findings suggest that this previously overlooked class of cross-reactive antibodies, exemplified by S309, may contribute to protection against disease caused by emerging variants through elicitation of effector functions.

Infection with severe acute respiratory syndrome coronavirus 2 associates with diverse symptoms, which can persist for months. While antiviral antibodies are protective, those targeting interferons and other immune factors are associated with adverse coronavirus disease 2019 (COVID-19) outcomes. Here we discovered that antibodies against specific chemokines were omnipresent post-COVID-19, were associated with favorable disease outcome and negatively correlated with the development of long COVID at 1 yr post-infection. Chemokine antibodies were also present in HIV-1 infection and autoimmune disorders, but they targeted different chemokines compared with COVID-19. Monoclonal antibodies derived from COVID-19 convalescents that bound to the chemokine N-loop impaired cell migration. Given the role of chemokines in orchestrating immune cell trafficking, naturally arising chemokine antibodies may modulate the inflammatory response and thus bear therapeutic potential.

Emergence of SARS-CoV-2 variants diminishes the efficacy of vaccines and antiviral monoclonal antibodies. Continued development of immunotherapies and vaccine immunogens resilient to viral evolution is therefore necessary. Using coldspot-guided antibody discovery, a screening approach that focuses on portions of the virus spike that are both functionally relevant and averse to change, we identified human neutralizing antibodies to highly conserved viral epitopes. Antibody fp.006 binds the fusion peptide and cross-reacts against coronaviruses of the fourgenera, including the nine human coronaviruses, through recognition of a conserved motif that includes the S2’ site of proteolytic cleavage. Antibody hr2.016 targets the stem helix and neutralizes SARS-CoV-2 variants. Antibody sd1.040 binds to subdomain 1, synergizes with antibody rbd.042 for neutralization and, like fp.006 and hr2.016, protects mice when present as bispecific antibody. Thus, coldspot-guided antibody discovery reveals donor-derived neutralizing antibodies that are cross-reactive withOrthocoronavirinae, including SARS-CoV-2 variants.One sentence summaryBroadly cross-reactive antibodies that protect from SARS-CoV-2 variants are revealed by virus coldspot-driven discovery.

Memory B cells (MBCs) generate rapid antibody responses upon secondary encounter with a pathogen. Here, we investigated the kinetics, avidity, and cross-reactivity of serum antibodies and MBCs in 155 SARS-CoV-2 infected and vaccinated individuals over a 16-month time frame. SARS-CoV-2-specific MBCs and serum antibodies reached steady-state titers with comparable kinetics in infected and vaccinated individuals. Whereas MBCs of infected individuals targeted both prefusion and postfusion Spike (S), most vaccine-elicited MBCs were specific for prefusion S, consistent with the use of prefusion-stabilized S in mRNA vaccines. Furthermore, a large fraction of MBCs recognizing postfusion S cross-reacted with human betacoronaviruses. The avidity of MBC-derived and serum antibodies increased over time resulting in enhanced resilience to viral escape by SARS-CoV-2 variants, including Omicron BA.1 and BA.2 sublineages, albeit only partially for BA.4 and BA.5 sublineages. Overall, the maturation of high-affinity and broadly reactive MBCs provides the basis for effective recall responses to future SARS-CoV-2 variants., iScience, 26 (1), ISSN:2589-0042

SARS-CoV-2 from alpha to epsilon As battles to contain the COVID-19 pandemic continue, attention is focused on emerging variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that have been deemed variants of concern because they are resistant to antibodies elicited by infection or vaccination or they increase transmissibility or disease severity. Three papers used functional and structural studies to explore how mutations in the viral spike protein affect its ability to infect host cells and to evade host immunity. Gobeil et al . looked at a variant spike protein involved in transmission between minks and humans, as well as the B1.1.7 (alpha), B.1.351 (beta), and P1 (gamma) spike variants; Cai et al . focused on the alpha and beta variants; and McCallum et al . discuss the properties of the spike protein from the B1.1.427/B.1.429 (epsilon) variant. Together, these papers show a balance among mutations that enhance stability, those that increase binding to the human receptor ACE2, and those that confer resistance to neutralizing antibodies. —VV

Probing CD4 T cell immunity to SARS-CoV-2 A better understanding of CD4 + T cell responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial to the design of effective next-generation vaccines. Low et al. defined and estimated the CD4 + T cell repertoire of convalescent COVID-19 patients. After sorting various CD4 + T cell subsets, they generated numerous T cell clones that reacted to the SARS-CoV-2 spike protein. A large number of T cell clones from almost all individuals recognized a small conserved immunodominant region within the spike protein receptor-binding domain (RBD). The researchers isolated T cell clones that broadly reacted to the spike protein of other coronaviruses, providing evidence for the recall of preexisting cross-reactive memory T cells after SARS-CoV-2 infection. Science , abg8985, this issue p. 1336

Introduction: Severe respiratory syndrome coronavirus 2 (SARS-CoV-2) uses the androgen receptor (AR), through ACE2 receptor and TMPRSS2, to enter nasal and upper airways epithelial cells. Genetic analyses revealed that HSD3B1 P1245C polymorphic variant increases dihydrotestosterone production and upregulation of TMPRSS2 with respect to P1245A variant, thus possibly influencing SARS-CoV-2 infection. Our aim was to characterize the HSD3B1 polymorphism status and its potential association with clinical outcomes in hospitalized patients with COVID-19 in Southern Switzerland.Materials and Methods: The cohort included 400 patients hospitalized for COVID-19 during the first wave between February and May 2020 in two different hospitals of Canton Ticino. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue blocks, and HSD3B1 gene polymorphism was evaluated by Sanger sequencing. Statistical associations were verified using different test.Results:HSD3B1 polymorphic variants were not associated with a single classical factor related to worse clinical prognosis in hospitalized patients with SARS-CoV-2. However, in specific subgroups, HSD3B1 variants played a clinical role: intensive care unit admission was more probable in patients with P1245C diabetes compared with P1245A individuals without this comorbidity and death was more associated with hypertensive P1245A>C cases than patients with P1245A diabetes without hypertension.Discussion: This is the first study showing that HSD3B1 gene status may influence the severity of SARS-CoV-2 infection. If confirmed, our results could lead to the introduction of HSD3B1 gene status analysis in patients infected with SARS-CoV-2 to predict clinical outcome.

IntroductionCirculating tumor DNA (ctDNA) correlates with the response to therapy in different types of cancer. However, in patients with locally advanced rectal cancer (LARC), little is known about how ctDNA levels change with neoadjuvant chemoradiation (Na-ChRT) and how they correlate with treatment response. This work aimed to explore the value of serial liquid biopsies in monitoring response after Na-ChRT with the hypothesis that this could become a reliable biomarker to identify patients with a complete response, candidates for non-operative management.Materials and MethodsTwenty-five consecutive LARC patients undergoing long-term Na-ChRT therapy were included. Applying next-generation sequencing (NGS), we characterized DNA extracted from formalin-fixed paraffin embedded diagnostic biopsy and resection tissue and plasma ctDNA collected at the following time points: the first and last days of radiotherapy (T0, Tend), at 4 (T4), 7 (T7) weeks after radiotherapy, on the day of surgery (Top), and 3–7 days after surgery (Tpost-op). On the day of surgery, a mesenteric vein sample was also collected (TIMV). The relationship between the ctDNA at those time-points and the tumor regression grade (TRG) of the surgical specimen was statistically explored.ResultsWe found no association between the disappearance of ctDNA mutations in plasma samples and pathological complete response (TRG1) as ctDNA was undetectable in the majority of patients from Tend on. However, we observed that the poor (TRG 4) response to Na-ChRT was significantly associated with a positive liquid biopsy at the Top.ConclusionsctDNA evaluation by NGS technology may identify LARC patients with poor response to Na-ChRT. In contrast, this technique does not seem useful for identifying patients prone to developing a complete response.

PURPOSE Despite extensive research on cancer and work-related outcomes, evidence from longitudinal cohort studies is limited, especially in young women with breast cancer (BC). We aimed to investigate employment trajectories in young BC survivors and to identify potential factors associated with changes in work activity. METHODS The HOHO European prospective multicenter cohort study enrolled 300 young women (≤ 40 years) with newly diagnosed BC. Women completed surveys at baseline and every 6 months for 3 years, then yearly for up to 10 years to assess, among other variables, employment status, sociodemographic, medical, and treatment data. Symptoms were assessed by the Breast Cancer Prevention Trial symptom scales and single items from the Cancer Rehabilitation Evaluation System. Univariable and multivariable multinomial logistic regression analyses identified factors associated with changes in employment status. RESULTS Among the 245 women included in this analysis, 85% were employed at the last individual post-baseline assessment (1 to 10 years). At 5 years, women had a 29.4% probability (95% CI: 23.6-35.5) of experiencing any reduction and a 14.9% probability (95% CI: 10.6-19.9) of experiencing any increase in work activities. Being enrolled in Switzerland (vs. Italy) and reporting more trouble in performing daily activities were significantly associated with work reduction. CONCLUSION Our results suggest that most young BC survivors remain employed in the long-term. IMPLICATIONS FOR CANCER SURVIVORS Regular evaluation of symptoms which may interfere with daily life and identification of financial discomfort is critical in providing timely and individually tailored interventions and in limiting unwanted reductions in work activities.

Infection by SARS-CoV-2 leads to diverse symptoms, which can persist for months. While antiviral antibodies are protective, those targeting interferons and other immune factors are associated with adverse COVID-19 outcomes. Instead, we discovered that antibodies against specific chemokines are omnipresent after COVID-19, associated with favorable disease, and predictive of lack of long COVID symptoms at one year post infection. Anti-chemokine antibodies are present also in HIV-1 infection and autoimmune disorders, but they target different chemokines than those in COVID-19. Monoclonal antibodies derived from COVID- 19 convalescents that bind to the chemokine N-loop impair cell migration. Given the role of chemokines in orchestrating immune cell trafficking, naturally arising anti-chemokine antibodies associated with favorable COVID-19 may be beneficial by modulating the inflammatory response and thus bear therapeutic potential.One-Sentence Summary:Naturally arising anti-chemokine antibodies associate with favorable COVID-19 and predict lack of long COVID.

SUMMARYThe recently emerged SARS-CoV-2 Omicron variant harbors 37 amino acid substitutions in the spike (S) protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody therapeutics. Here, we show that the Omicron RBD binds to human ACE2 with enhanced affinity relative to the Wuhan-Hu-1 RBD and acquires binding to mouse ACE2. Severe reductions of plasma neutralizing activity were observed against Omicron compared to the ancestral pseudovirus for vaccinated and convalescent individuals. Most (26 out of 29) receptor-binding motif (RBM)-directed monoclonal antibodies (mAbs) lost in vitro neutralizing activity against Omicron, with only three mAbs, including the ACE2-mimicking S2K146 mAb1, retaining unaltered potency. Furthermore, a fraction of broadly neutralizing sarbecovirus mAbs recognizing antigenic sites outside the RBM, including sotrovimab2, S2X2593 and S2H974, neutralized Omicron. The magnitude of Omicron-mediated immune evasion and the acquisition of binding to mouse ACE2 mark a major SARS-CoV-2 mutational shift. Broadly neutralizing sarbecovirus mAbs recognizing epitopes conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.

BackgroundThe worldwide pandemic situation forced many hospitals to adapt COVID-19 management strategies. In this scenario, theSwiss Academy of Medical Sciences(SAMW/ASSM) organized national guidelines based on expert opinion to identify Do-Not-Resuscitate (DNR) patients, to reduce futile ICU admission and resource misuse. However, the practical impact of this standardized national protocol has not been yet evaluated. In our specialized COVID-19 Center, we investigated characteristics and mortality of DNR patients identified according to national standardized protocol, comparing them to non-DNR patients.MethodsThis was a pilot retrospective validation study, evaluating consecutive hospital admitted COVID-19 patients. Primary outcome was 30-days survival ofDNR patientsin comparison to thecontrol group. Secondary outcomes reported quality of treatment of deceased patients, especially of agitation/sedation and dyspnea, using respectively the Richmond Agitation-Sedation Scale – Palliative care (RASS-PAL) for sedation and agitation (+4/-5) and the modified Borg Scale for dyspnea (1-10).ResultsFrom March 16 to April 1, 2020, 213 consecutive patients were triaged; at 30-days follow-up, 9 patients (22.5%) died in theDNR group, 4 (2.2%) in thecontrol group. The higher mortality rate in theDNR groupwas further confirmed by Log-Rank Mantel-Cox (23.104, p < 0.0001). In theDNR-groupdeceased patients, end-of-life support was performed with oxygen (100%), opioids (100%) and sedatives (89%); the mean RASS-PAL improved from 2.2 to -1.8 (p < 0.0001) and the Borg scale improved from 5.7 to 4.7 (p = 0.581).ConclusionA national standardized protocol identified patients at higher risk of short-term death. Although the legal status of DNRs varies from country to country, the implementation of national standardized protocol could be the way to guarantee a better treatment of COVID-19 patients in a pandemic situation with limited resources.

• We conducted a Swiss survey on patterns of practice during COVID-19 pandemic. • Dedicated IT solutions were implemented in all radiation-oncology departments. • Upfront endocrine treatments for breast and prostate cancer were privileged. • Use of hypofractionation for breast, rectal cancer and palliation was increased.

Purpose Helical tomotherapy (HT) has been recently introduced in the neoadjuvant treatment of locally advanced rectal cancer. Aim of this study is to report the toxicity and local control rates of a large series of locally advanced rectal cancer patients treated with neoadjuvant chemotherapy and HT under daily image guidance followed by surgery. Methods Data from 117 locally advanced rectal cancer patients treated at two Swiss Radiotherapy departments were collected and analyzed. Radiotherapy consisted of 45 Gy (1.8 Gy/fraction, 5 fractions/week delivered in 5 weeks) to the regional pelvic lymph nodes. Seventy patients also received a simultaneous integrated boost (SIB) up to 50 Gy to the tumor and involved nodes (2 Gy/fraction, 5 fractions/week delivered in 5 weeks). Chemotherapy consisted of capecitabine 825 mg/m2, twice daily, during the irradiation days. After a median interval of 59 days [95% confidence interval (CI) 53–65 days), all patients underwent surgery. Results Median follow-up was 45 months (range 4–90 months). The overall rate of acute grade 2–4 toxicity was 18.8% (n = 22). Four patients (3.4%) presented a grade 3 dermatitis (n = 1) or diarrhea (n = 3), and 1 (0.8%) demonstrated grade 4 rectal toxicity. No patients presented with grade ≥ 3 hematologic toxicity. Six patients (5.1%) had late grade 3 gastrointestinal toxicity. The 4-year local control rate was 88.4% (95% CI 87.5–88.5%). Conclusions Neoadjuvant chemoradiotherapy delivered with HT under daily image guidance is well tolerated and shows a high 4-year local control rates.

SARS-CoV-2 entry is mediated by the spike (S) glycoprotein which contains the receptor-binding domain (RBD) and the N-terminal domain (NTD) as the two main targets of neutralizing antibodies (Abs). A novel variant of concern (VOC) named CAL.20C (B.1.427/B.1.429) was originally detected in California and is currently spreading throughout the US and 29 additional countries. It is unclear whether antibody responses to SARS-CoV-2 infection or to the prototypic Wuhan-1 isolate-based vaccines will be impacted by the three B.1.427/B.1.429 S mutations: S13I, W152C and L452R. Here, we assessed neutralizing Ab responses following natural infection or mRNA vaccination using pseudoviruses expressing the wildtype or the B.1.427/B.1.429 S protein. Plasma from vaccinated or convalescent individuals exhibited neutralizing titers, which were reduced 3-6 fold against the B.1.427/B.1.429 variant relative to wildtype pseudoviruses. The RBD L452R mutation reduced or abolished neutralizing activity of 14 out of 35 RBD-specific monoclonal antibodies (mAbs), including three clinical-stage mAbs. Furthermore, we observed a complete loss of B.1.427/B.1.429 neutralization for a panel of mAbs targeting the N-terminal domain due to a large structural rearrangement of the NTD antigenic supersite involving an S13I-mediated shift of the signal peptide cleavage site. These data warrant closer monitoring of signal peptide variants and their involvement in immune evasion and show that Abs directed to the NTD impose a selection pressure driving SARS-CoV-2 viral evolution through conventional and unconventional escape mechanisms.

The identification of CD4+ T cell epitopes is essential for the design of effective vaccines capable of inducing neutralizing antibodies and long-term immunity. Here we demonstrate in COVID-19 patients a robust CD4+ T cell response to naturally processed SARS-CoV-2 Spike and Nucleoprotein, including effector, helper and memory T cells. By characterizing 2,943 Spike-reactive T cell clones, we found that 34% of the clones and 93% of the patients recognized a conserved immunodominant region encompassing residues S346-365 in the RBD and comprising three nested HLA-DR and HLA-DP restricted epitopes. By using pre- and post-COVID-19 samples and Spike proteins from alpha and beta coronaviruses, we provide in vivo evidence of cross-reactive T cell responses targeting multiple sites in the SARS-CoV-2 Spike protein. The possibility of leveraging immunodominant and cross-reactive T helper epitopes is instrumental for vaccination strategies that can be rapidly adapted to counteract emerging SARS-CoV-2 variants.

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) transmission is uncontrolled in many parts of the world, compounded in some areas by higher transmission potential of the B1.1.7 variant now seen in 50 countries. It is unclear whether responses to SARS-CoV-2 vaccines based on the prototypic strain will be impacted by mutations found in B.1.1.7. Here we assessed immune responses following vaccination with mRNA-based vaccine BNT162b2. We measured neutralising antibody responses following a single immunization using pseudoviruses expressing the wild-type Spike protein or the 8 amino acid mutations found in the B.1.1.7 spike protein. The vaccine sera exhibited a broad range of neutralising titres against the wild-type pseudoviruses that were modestly reduced against B.1.1.7 variant. This reduction was also evident in sera from some convalescent patients. Decreased B.1.1.7 neutralisation was also observed with monoclonal antibodies targeting the N-terminal domain (9 out of 10), the Receptor Binding Motif (RBM) (5 out of 31), but not in neutralising mAbs binding outside the RBM. Introduction of the E484K mutation in a B.1.1.7 background to reflect newly emerging viruses in the UK led to a more substantial loss of neutralising activity by vaccine-elicited antibodies and mAbs (19 out of 31) over that conferred by the B.1.1.7 mutations alone. E484K emergence on a B.1.1.7 background represents a threat to the vaccine BNT162b.

Background Advanced breast cancer (BC) impact immune cells in the blood but whether such effects may reflect the presence of early BC and its therapeutic management remains elusive. Methods To address this question, we used multiparametric flow cytometry to analyze circulating leukocytes in patients with early BC (n = 13) at the time of diagnosis, after surgery, and after adjuvant radiotherapy, compared to healthy individuals. Data were analyzed using a minimally supervised approach based on FlowSOM algorithm and validated manually. Results At the time of diagnosis, BC patients have an increased frequency of CD117+CD11b+ granulocytes, which was significantly reduced after tumor removal. Adjuvant radiotherapy increased the frequency of CD45RO+ memory CD4+ T cells and CD4+ regulatory T cells. FlowSOM algorithm analysis revealed several unanticipated populations, including cells negative for all markers tested, CD11b+CD15low, CD3+CD4−CD8−, CD3+CD4+CD8+, and CD3+CD8+CD127+CD45RO+ cells, associated with BC or radiotherapy. Conclusions This study revealed changes in blood leukocytes associated with primary BC, surgical removal, and adjuvant radiotherapy. Specifically, it identified increased levels of CD117+ granulocytes, memory, and regulatory CD4+ T cells as potential biomarkers of BC and radiotherapy, respectively. Importantly, the study demonstrates the value of unsupervised analysis of complex flow cytometry data to unravel new cell populations of potential clinical relevance.

Aim: Recommendations for managing patients with nasopharyngeal carcinoma (NPC) in non-endemic areas are largely derived from studies conducted in endemic areas. We analysed the impact of treatment approaches on survival in non-endemic areas. Methods: In an international, multicentre, retrospective study, we analyse consecutive patients with NPC diagnosed between 2004 and 2017 in 36 hospitals from 11 countries. Treatment was categorised as non-intensive (NIT), including radiotherapy alone or concomitant chemoradiotherapy (cCRT), and intensive (IT) including cCRT preceded by and/or followed by chemotherapy (CT). The impact of IT on overall survival (OS) and disease-free survival (DFS) was adjusted for all the available potential confounders. Results: Overall, 1021 and 1113 patients were eligible for overall survival (OS) and disease-free survival (DFS) analyses, respectively; 501 and 554 with Epstein Barr-encoded RNA (EBER) status available. In the whole group, 5-year OS was 84% and DFS 65%. The use of NIT was associated with a risk of death or recurrence 1.37 times higher than patients receiving IT. Patients submitted to NIT and induction CT thorn concurrent concomitant chemo and three-dimensional Conformal Radiation Therapy (3DCRT) had a risk of death or recurrence 1.5 and 1.7 times higher than patients treated with induction CT + cCRT with intensity-modulated radiotherapy (IMRT), respectively. The IT had no impact on OS in neither patients with EBER+ nor in patients with EBER-; IT showed better DFS in EBER+ but not in patients with EBER-. Conclusions: In low-incidence areas, patients with NPC treated with induction CT followed by concurrent IMRT cCRT achieved the highest DFS rate. The benefit of IT on DFS was restricted to patients with EBERthorn, suggesting that additional therapy offers no advantages in EBER- cases. (C) 2021 Elsevier Ltd. All rights reserved.

Analysis of the specificity and kinetics of neutralizing antibodies (nAbs) elicited by SARS-CoV-2 infection is crucial for understanding immune protection and identifying targets for vaccine design. In a cohort of 647 SARS-CoV-2-infected subjects, we found that both the magnitude of Ab responses to SARS-CoV-2 spike (S) and nucleoprotein and nAb titers correlate with clinical scores. The receptor-binding domain (RBD) is immunodominant and the target of 90% of the neutralizing activity present in SARS-CoV-2 immune sera. Whereas overall RBD-specific serum IgG titers waned with a half-life of 49 days, nAb titers and avidity increased over time for some individuals, consistent with affinity maturation. We structurally defined an RBD antigenic map and serologically quantified serum Abs specific for distinct RBD epitopes leading to the identification of two major receptor-binding motif antigenic sites. Our results explain the immunodominance of the receptor-binding motif and will guide the design of COVID-19 vaccines and therapeutics., Graphical Abstract, Highlights • SARS-CoV-2 RBD is immunodominant and accounts for 90% of serum neutralizing activity • RBD antibodies decline with a half-life of ∼50 days, but their avidity increases • Structural definition of a SARS-CoV-2 RBD antigenic map using monoclonal antibodies • ACE2-binding site dominates SARS-CoV-2 polyclonal neutralizing antibody responses, Serological analyses of ∼650 SARS-CoV-2-exposed individuals show that 90% of the serum or plasma neutralizing activity targets the virus receptor-binding domain, with structural insights revealing how distinct types of neutralizing antibodies targeting the ACE2-binding site dominate the immune response against SARS-CoV-2 spike.

Aim To assess the educational needs, role and perceptions in palliative care issues of radiation oncologists (ROs) and trainees. Background 1/3 of radiotherapy patients are treated with palliative intent. Conversely, education and role that ROs have in the palliative care process are not well established, neither in terms of how they perceive their competence nor whether it is important to improve training, research and attention in palliative care issues at radiotherapy congresses. Material and Methods Literature systematic review in National Library of Medicine and Cochrane databases with 11 relevant issues to be identified. One doctor made first selection of articles, a second one confirmed their eligibility. Results 722 articles reviewed, 19 selected. 100% recognize the importance of palliative care in radiotherapy, 89.4% the need of training in palliative care for ROs, 68.4% the necessity of improving the resident programs, 63.1% the importance of skilled ROs in palliative care, 63.1% the need of better communication skills and pain management (47.3%), 52.6%, the perception of inadequate training in palliative care, 36.8% the lack of research and palliative care topics in radiotherapy meetings, 21% the absence of adequate guidelines regarding palliative care approaches, 42.1% the importance of the ROs in palliative care teams and 26.3% the lack of their involvement. Conclusion Palliative care has an important role in radiotherapy but it seems ROs still need more training. It is necessary to improve training programs, increment palliative care research in radiotherapy, giving more attention to palliative care themes at radiotherapy congresses. This could lead to a better integration of radiotherapists in multidisciplinary palliative care teams in the future.

To report outcomes of a population of anal cancer patients treated with modern intensity-modulated radiotherapy and daily image-guided radiotherapy techniques. We analyzed data of 155 patients consecutively treated with intensity-modulated radiotherapy +/− chemotherapy in three radiotherapy departments. One hundred twenty-two patients presented a stage II–IIIA disease. Chemotherapy was administered in 138 patients, mainly using mitomycin C and 5-fluorouracil (n = 81). All patients received 36 Gy (1.8 Gy/fraction) on the pelvic and inguinal nodes, on the rectum, on the mesorectum and on the anal canal, and a sequential boost up to a total dose of 59.4 Gy (1.8 Gy/fraction) on the anal canal and on the nodal gross tumor volumes. Median follow-up was 38 months (interquartile range 12–51). Toxicity data were available for 143 patients: 22% of them presented a G3+ acute toxicity, mainly as moist desquamation (n = 25 patients) or diarrhea (n = 10). Three patients presented a late grade 3 gastrointestinal toxicity (anal incontinence). No grade 4 acute or late toxicity was recorded. Patients treated with fixed-gantry IMRT delivered with a sliding window technique presented a significantly higher risk of acute grade 3 (or more) toxicity compared to those treated with VMAT or helical tomotherapy (38.5 vs 15.3%, p = 0.049). Actuarial 4-year local control rate was 82% (95% CI 76–91%). Modern intensity-modulated radiotherapy with daily image-guided radiotherapy is effective and safe in treating anal cancer patients and should be considered the standard of care in this clinical setting.

Objective: To determine the recommended dose (RD) of gefitinib when combined with concomitant radiotherapy (RT) in a preoperative setting in patients with locally advanced rectal cancer. Secondary objectives were to evaluate acute toxicities, pathological response rate, progression-free and overall survival (OS). Materials and Methods: 20 patients with cT3-4 or cN+ cM0 tumors were enrolled. The planned RT consisted in 50 Gy given in 2 daily fractions of 1.25 Gy in 4 weeks. During RT, gefitinib was planned to be given orally once daily with 2 successive dose levels: 250 mg and 500 mg. Rectal surgery was scheduled 5 - 6 weeks after completion of RT. The median follow-up for all patients was 57 months. Results: Among the first cohort of 6 patients, 1 patient presented a dose limiting toxicity (DLT) (Grade 3 diarrhea/dehydration). In the second cohort, 2/6 patients presented with the same DLT so that 250 mg was considered as the RD. Main acute toxicities consisted in diarrhea (grade 2 - 3, 63%), and skin reaction (in RT fields grade 2 - 3 in 42%). The 5-year actuarial OS and loco-regional control rates were of 80% and 84% respectively. Conclusion: The concomitant daily administration of 250 mg of gefitinib with 50 Gy preoperative RT is feasible with manageable toxicity. The major pathologic response rate is encouraging, though it needs further confirmation. Distant metastasis still represents a concern and new strategies to overcome this issue are warranted.

A treatment planning study was performed to compare volumetric-modulated arc radiotherapy against conventional fixed field IMRT.CT datasets of 10 patients affected by carcinoma of the anal canal were included and five plans were generated for each case: fixed beam IMRT, single (RA1)- and double (RA2)-modulated arcs with the RapidArc technique. Dose prescription was set according to a simultaneous integrated boost strategy to 59.4 Gy to the primary tumour PTVI (at 1.8 Gy/fraction) and to 49.5 Gy to risk area including inguinal nodes, PTVII. Planning objectives for PTV were minimum dose95%, maximum dose107%; for organs at risk (OARs): bladder (mean45 Gy, D(2%)56 Gy, D(30%)35 Gy), femurs (D(2%)47 Gy), small bowel (mean30 Gy, D(2%)56 Gy). MU and delivery time scored treatment efficiency.All techniques fulfilled objectives on maximum dose. Some deviations were observed on minimum dose for PTV. Uniformity (D(5)-D(95)) on PTVI resulted 6.6+/-1.4% for IMRT and ranged from 5.7+/-0.3% to 8.1+/-0.8% for RA plans (+/-1 standard deviation). Conformity index (CI(95%)) was 1.3+/-0.1 (IMRT) and 1.4+/-0.1 (all RA techniques). Bladder: all techniques resulted equivalent above 40 Gy; V(30 Gy) approximately 57% for the double arcs, approximately 61% for RA1 and approximately 65% for IMRT. Femurs: maximum dose was of the order of 41-42 Gy for all RA plans and approximately 45 Gy for IMRT. Small bowel: all techniques respected planning objectives. The number of computed MU/fraction was 1531+/-206 (IMRT), 468+/-95 (RA1), and 545+/-80 (RA2) leading to differences in treatment time: 9.4+/-1.7 min for IMRT vs. 1.1+/-0.0 min for RA1 and 2.6+/-0.0 min for double arcs.RapidArc showed improvements in organs at risk and healthy tissue sparing with uncompromised target coverage when double arcs are applied. Optimal results were also achieved anyway with IMRT plans.

Approximately, twenty years ago, the Rare Cancer Network (RCN) was formed in Lausanne, Switzerland, to support the study of rare malignancies. The RCN has grown over the years and now includes 130 investigators from twenty-four nations on six continents. The network held its first international symposium in Nice, France, on March 21-22, 2014. The proceedings of that meeting are presented in two companion papers. This manuscript reviews the history of the growth of the RCN and contains the abstracts of fourteen oral presentations made at the meeting of prior RCN studies. From 1993 to 2014, 74 RCN studies have been initiated, of which 54 were completed, 10 are in progress or under analysis, and 9 were stopped due to poor accrual. Forty-four peer reviewed publications have been written on behalf of the RCN.

Combined chemoradiation therapy is the gold standard in the treatment of squamous cell anal cancer (SCAC). However, even if the response rate is very high, many patients eventually relapse or experience a reccurrence, thus requiring an invasive surgical procedure that has severe side effects. Most SCAC tumors overexpress epidermal growth factor receptor (EGFR); therefore, it is reasonable to consider anti-EGFR drugs as a new treatment option, as demonstrated by anecdotal reports. Promising results obtained in other solid tumors, both squamous and non-squamous, have revealed that an increase in the EGFR gene copy number may predict the efficacy of anti-EGFR therapies, while the presence of mutations in downstream members of the EGFR pathway may confer resistance. These markers have been only sporadically considered in SCAC.We investigated the status of the EGFR gene using FISH and examined KRAS, BRAF, and PIK3CA hot-spots mutations using sequencing analysis in a cohort of 84 patients affected by SCAC.Twenty-eight patients (34%) showed an increase in EGFR gene copy number due to amplification (4%) or to polysomy (30%). KRAS and PIK3CA gene mutations were found in 4 (5%) and 13 patients (16%), respectively. No mutations were found in the BRAF gene.The characterization of the EGFR pathway may help in identifying different subgroups of SCAC that have specific molecular features, which may have implications in what targeted therapies are used to treat each patient.

Preoperative radiotherapy (RT) followed by surgery is widely accepted in the treatment of locally advanced rectal cancer (LARC). This study aimed to estimate at the population-based level the impact of preoperative RT on overall survival (OS) and cancer-specific survival (CSS) in LARCs diagnosed in Southern Switzerland between 1996 and 2007. All patients with LARC were selected from the Ticino Cancer Registry database. Patients were categorized according to the first administered treatment: preoperative radiotherapy (RT) followed by surgery (RT+) versus surgery (RT-). Clinical-pathological characteristics and 5-year OS and CSS were analysed. Among 384 patients with LARC, 54% underwent preoperative RT, occurring more frequently in the mid-distal part of the rectum compared with the RT- group (74.8 vs. 29.8%, respectively). Both 5-year OS and CSS significantly improved in RT+ patients (OS: 68 vs. 54%, respectively; CSS: 71 vs. 63%, respectively). The adjusted hazard ratio for all death was equal to 0.66 (95% confidence interval: 0.46; 0.97); similarly, the hazard ratio for cancer-specific death was 0.63 (95% confidence interval: 0.39; 0.99). These observational population-based results, after controlling for most important diagnostic and clinical prognostic factors, confirm the benefit of preoperative RT of LARC, even if the magnitude seems greater than expected in clinical trials results. Additional studies are needed, particularly with regard to the possible effect of standardized staging procedure and multidisciplinary discussion on patient outcome.