The Landscape of Adoptive Cellular Therapies in Ovarian Cancer

Ovarian cancers are typically poorly immunogenic and have demonstrated disappointing responses to immune checkpoint inhibitor (ICI) therapy. Adoptive cellular therapy (ACT) offers an alternative method of harnessing the immune system that has shown promise, especially with the success of chimeric antigen receptor T-cell (CAR-T) therapy in haematologic malignancies. So far, ACT has led to modest results in the treatment of solid organ malignancies. This review explores the possibility of ACT as an effective alternative or additional treatment to current standards of care in ovarian cancer. We will highlight the potential of ACTs, such as CAR-T, T-cell receptor therapy (TCR-T), tumour-infiltrating lymphocytes (TILs) and cell-based vaccines, whilst also discussing their challenges. We will present clinical studies for these approaches in the treatment of immunologically 'cold' ovarian cancer and consider the rationale for future research.

Outcomes of the SARS-CoV-2 omicron (B.1.1.529) variant outbreak among vaccinated and unvaccinated patients with cancer in Europe: results from the retrospective, multicentre, OnCovid registry study

BACKGROUND

The omicron (B.1.1.529) variant of SARS-CoV-2 is highly transmissible and escapes vaccine-induced immunity. We aimed to describe outcomes due to COVID-19 during the omicron outbreak compared with the prevaccination period and alpha (B.1.1.7) and delta (B.1.617.2) waves in patients with cancer in Europe.

METHODS

In this retrospective analysis of the multicentre OnCovid Registry study, we recruited patients aged 18 years or older with laboratory-confirmed diagnosis of SARS-CoV-2, who had a history of solid or haematological malignancy that was either active or in remission. Patient were recruited from 37 oncology centres from UK, Italy, Spain, France, Belgium, and Germany. Participants were followed up from COVID-19 diagnosis until death or loss to follow-up, while being treated as per standard of care. For this analysis, we excluded data from centres that did not actively enter new data after March 1, 2021 (in France, Germany, and Belgium). We compared measures of COVID-19 morbidity, which were complications from COVID-19, hospitalisation due to COVID-19, and requirement of supplemental oxygen and COVID-19-specific therapies, and COVID-19 mortality across three time periods designated as the prevaccination (Feb 27 to Nov 30, 2020), alpha-delta (Dec 1, 2020, to Dec 14, 2021), and omicron (Dec 15, 2021, to Jan 31, 2022) phases. We assessed all-cause case-fatality rates at 14 days and 28 days after diagnosis of COVID-19 overall and in unvaccinated and fully vaccinated patients and in those who received a booster dose, after adjusting for country of origin, sex, age, comorbidities, tumour type, stage, and status, and receipt of systemic anti-cancer therapy. This study is registered with ClinicalTrials.gov, NCT04393974, and is ongoing.

FINDINGS

As of Feb 4, 2022 (database lock), the registry included 3820 patients who had been diagnosed with COVID-19 between Feb 27, 2020, and Jan 31, 2022. 3473 patients were eligible for inclusion (1640 [47·4%] were women and 1822 [52·6%] were men, with a median age of 68 years [IQR 57-77]). 2033 (58·5%) of 3473 were diagnosed during the prevaccination phase, 1075 (31·0%) during the alpha-delta phase, and 365 (10·5%) during the omicron phase. Among patients diagnosed during the omicron phase, 113 (33·3%) of 339 were fully vaccinated and 165 (48·7%) were boosted, whereas among those diagnosed during the alpha-delta phase, 152 (16·6%) of 915 were fully vaccinated and 21 (2·3%) were boosted. Compared with patients diagnosed during the prevaccination period, those who were diagnosed during the omicron phase had lower case-fatality rates at 14 days (adjusted odds ratio [OR] 0·32 [95% CI 0·19-0·61) and 28 days (0·34 [0·16-0·79]), complications due to COVID-19 (0·26 [0·17-0·46]), and hospitalisation due to COVID-19 (0·17 [0·09-0·32]), and had less requirements for COVID-19-specific therapy (0·22 [0·15-0·34]) and oxygen therapy (0·24 [0·14-0·43]) than did those diagnosed during the alpha-delta phase. Unvaccinated patients diagnosed during the omicron phase had similar crude case-fatality rates at 14 days (ten [25%] of 40 patients vs 114 [17%] of 656) and at 28 days (11 [27%] of 40 vs 184 [28%] of 656) and similar rates of hospitalisation due to COVID-19 (18 [43%] of 42 vs 266 [41%] of 652) and complications from COVID-19 (13 [31%] of 42 vs 237 [36%] of 659) as those diagnosed during the alpha-delta phase.

INTERPRETATION

Despite time-dependent improvements in outcomes reported in the omicron phase compared with the earlier phases of the pandemic, patients with cancer remain highly susceptible to SARS-CoV-2 if they are not vaccinated against SARS-CoV-2. Our findings support universal vaccination of patients with cancer as a protective measure against morbidity and mortality from COVID-19.

FUNDING

National Institute for Health and Care Research Imperial Biomedical Research Centre and the Cancer Treatment and Research Trust.

Abstract 1591: Convergence of antigenic diversity and Tex-cell stability fatally constrains immune surveillance in non-small cell lung cancer (TRACERx) and HIV-1 infection (Protocol C)

T cells recognize cognate antigen and elicit effector function to eliminate target cells. In chronic infection and cancer, exhausted T cells with impaired effector function and narrow TCR repertoires must respond to vast and diverse antigenic landscapes, favoring immune escape. Here we test whether T cell exhaustion and antigenic diversity converge to drive fatal immune failure in chronic infection and cancer. We leveraged over 600 primary longitudinal samples from the Protocol C (IAVI) and TRACERx (CRUK) studies to track the natural course of HIV-1 infection and non-small cell lung cancer (NSCLC), respectively, using high parameter flow cytometry, genome sequencing and TCRseq, complemented with focused scRNAseq and antigen specific profiling. In both diseases systemic Tcf1-Tox+Eomes+PD1+ T (Tex) cells track antigen burden and predict adverse outcome, independent of host clinical status. In HIV-1 infection, Tex cells are clonally restricted and rapid Gag RNA sequence divergence accompanies higher viral loads and lower CD4 counts. Similarly, in lung cancer peripheral Tex cells harbor hyper-expanded TCRs, contract after resection and reconstitute at recurrence with strikingly preserved clonal hierarchies, creating a ‘specificity gap’ that could be exploited by subclonal evolution. Commensurate with this model, we discover that a high level of systemic Tex cells coupled with either elevated Gag diversity in HIV-1 infection, or higher mutational or copy number heterogeneity in lung cancer defines patients with the poorest clinical outcome. We propose a unifying model of immune failure in chronic infection and cancer where genomic diversity and T cell exhaustion co-ordinately diminish human immune protection.

Citation Format: James L. Reading, Rachel Rosenthal, Oriol Pich, Samuel Gamble, Seng Anakin Ung, Teerapon Sahwangarrom, Betty Gration, Yien Ning Sophia Wong, Lucas Black, Benny Chain, Jonathan Hare, Sergio A. Quezada, Charles Swanton. Convergence of antigenic diversity and Tex-cell stability fatally constrains immune surveillance in non-small cell lung cancer (TRACERx) and HIV-1 infection (Protocol C) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1591.

Systematic Evaluation of the Immune Environment of Small Intestinal Neuroendocrine Tumors

PURPOSE

The immune tumor microenvironment and the potential therapeutic opportunities for immunotherapy in small intestinal neuroendocrine tumors (siNET) have not been fully defined.

EXPERIMENTAL DESIGN

Herein, we studied 40 patients with primary and synchronous metastatic siNETs, and matched blood and normal tissue obtained during surgery. We interrogated the immune checkpoint landscape using multi-parametric flow cytometry. In addition, matched FFPE tissue was obtained for multi-parametric IHC to determine the relative abundance and distribution of T-cell infiltrate. Tumor mutational burden (TMB) was also assessed and correlated with immune infiltration.

RESULTS

Effector tumor-infiltrating lymphocytes (TIL) had a higher expression of PD-1 in the tumor microenvironment compared with the periphery. In addition, CD8+ TILs had a significantly higher co-expression of PD-1/ICOS and PD-1/CTLA-4 (cytotoxic T lymphocyte antigen-4) and higher levels of PD-1 expression compared with normal tissue. IHC revealed that the majority of cases have ≤10% intra-tumoral T cells but a higher number of peri-tumoral T cells, demonstrating an "exclusion" phenotype. Finally, we confirmed that siNETs have a low TMB compared with other tumor types in the TCGA database but did not find a correlation between TMB and CD8/Treg ratio.

CONCLUSIONS

Taken together, these results suggest that a combination therapy approach will be required to enhance the immune response, using PD-1 as a checkpoint immunomodulator backbone in combination with other checkpoint targeting molecules (CTLA-4 or ICOS), or with drugs targeting other pathways to recruit "excluded" T cells into the tumor microenvironment to treat patients with siNETs.

Systemic Anti-Cancer Therapy and Metastatic Cancer Are Independent Mortality Risk Factors during Two UK Waves of the COVID-19 Pandemic at University College London Hospital

An increased mortality risk was observed in patients with cancer during the first wave of COVID-19. Here, we describe determinants of mortality in patients with solid cancer comparing the first and second waves of COVID-19. A retrospective analysis encompassing two waves of COVID-19 (March-May 2020; December 2020-February 2021) was performed. 207 patients with cancer were matched to 452 patients without cancer. Patient demographics and oncological variables such as cancer subtype, staging and anti-cancer treatment were evaluated for association with COVID-19 mortality. Overall mortality was lower in wave two compared to wave one, HR 0.41 (95% CI: 0.30-0.56). In patients with cancer, mortality was 43.6% in wave one and 15.9% in wave two. In hospitalized patients, after adjusting for age, ethnicity and co-morbidities, a history of cancer was associated with increased mortality in wave one but not wave two. In summary, the second UK wave of COVID-19 is associated with lower mortality in hospitalized patients. A history of solid cancer was not associated with increased mortality despite the dominance of the more transmissible B.1.1.7 SARS-CoV-2 variant. In both waves, metastatic disease and systemic anti-cancer treatment appeared to be independent risk factors for death within the combined cancer cohort.

Specialist palliative and end-of-life care for patients with cancer and SARS-CoV-2 infection: a European perspective

BACKGROUND

Specialist palliative care team (SPCT) involvement has been shown to improve symptom control and end-of-life care for patients with cancer, but little is known as to how these have been impacted by the COVID-19 pandemic. Here, we report SPCT involvement during the first wave of the pandemic and compare outcomes for patients with cancer who received and did not receive SPCT input from multiple European cancer centres.

METHODS

From the OnCovid repository (N = 1318), we analysed cancer patients aged ⩾18 diagnosed with COVID-19 between 26 February and 22 June 2020 who had complete specialist palliative care team data (SPCT+ referred; SPCT- not referred).

RESULTS

Of 555 eligible patients, 317 were male (57.1%), with a median age of 70 years (IQR 20). At COVID-19 diagnosis, 44.7% were on anti-cancer therapy and 53.3% had ⩾1 co-morbidity. Two hundred and six patients received SPCT input for symptom control (80.1%), psychological support (54.4%) and/or advance care planning (51%). SPCT+ patients had more 'Do not attempt cardio-pulmonary resuscitation' orders completed prior to (12.6% versus 3.7%) and during admission (50% versus 22.1%, p < 0.001), with more SPCT+ patients deemed suitable for treatment escalation (50% versus 22.1%, p < 0.001). SPCT involvement was associated with higher discharge rates from hospital for end-of-life care (9.7% versus 0%, p < 0.001). End-of-life anticipatory prescribing was higher in SPCT+ patients, with opioids (96.3% versus 47.1%) and benzodiazepines (82.9% versus 41.2%) being used frequently for symptom control.

CONCLUSION

SPCT referral facilitated symptom control, emergency care and discharge planning, as well as high rates of referral for psychological support than previously reported. Our study highlighted the critical need of SPCTs for patients with cancer during the pandemic and should inform service planning for this population.

Abstract LB004: Nivolumab (NIVO) and ipilimumab (IPI) treatment in prostate cancer with an immunogenic signature: cohort 1 of the NEPTUNES multi-centre, two-stage biomarker-selected Phase II trial

Background: Responses to checkpoint inhibitor (CPI) monotherapy in patients with metastatic castration resistant prostate cancer (mCRPC) have been limited. This is likely due to a “cold” tumour immune microenvironment. We hypothesised that patients with mCRPC will be more likely to respond if they have a positive immunogenic signature (ImS+). We report the response/safety for NIVO + IPI in pts with ImS+ mCRPC from cohort 1 of the NEPTUNES study.

Methods: Pts with mCRPC who progressed following ≥1 line of therapy and ImS+ were eligible. ImS+ was defined by ≥1 of the following: 1) mismatch repair deficient (MMRD) by immunohistochemistry (IHC); 2) DNA damage repair deficient (DDRD) excluding MMRD, detected by the UW-OncoPlex targeted exome sequencing assay and; 3) high tumour infiltrating lymphocytes (TILs) on multiplexed immunohistochemistry (CD4, CD8 or FoxP3+ &gt;20% nucleated cells). Treatment was NIVO 1 mg/kg + IPI 3 mg/kg Q3W for 4 doses, then NIVO 480 mg every 4 weeks. Primary endpoint was composite response rate (CRR) defined by ≥1 of the following: 1) radiological response by RECIST 1.1; 2) PSA response ≥50%; 3) conversion of circulating tumour cells (CTC) at week 9. Treatment would be deemed ineffective if the CRR was &lt;20%. Results: 50/211 pts were ImS+, and 35 patients were treated with NIVO/IPI with a median follow up of 7.2 months (range 2.1-20.5). The overall CRR was 9/35 (26%, 95%CI 12-43%). The ImS+ determinants in responding/all treated patients included MMRD (n=4/5), BRCA1/2 (n=3/4), exclusively high TILs (n=2/9) and CDK12 (n=1/7). In responders, median duration of response was 4.9 months (range 1.8-19.7). Grade 3-4 treatment-related adverse events occurred in 17/35 (49%).

Conclusions: NIVO + IPI demonstrated significant activity in biomarker selected, pre-treated pts with mCRPC. The safety profile is consistent with this dosing schedule. Accrual to expansion cohort 2 started in September 2020.

Determinants of immunogenic signature in responding patientsPatientInflammatory Infiltrate (%)MMRD (Y/N)DDRD (Y/N)TMB Mut/MBNEP-03340NN1NEP-03610NY Biallelic BRCA24NEP-0964NY Biallelic BRCA28NEP-1093Y MSH2/MSH6N14NEP-12625Y MSH2/MSH6N21NEP-13110Y PMS2/MLH1N13NEP-15920Y MSH2/MSH6Y BRCA127NEP-16525NY Biallelic CDK125NEP-06930NN1

Citation Format: Mark D. Linch, Yien Ning Sophia Wong, Robert Jones, Peter Sankey, Debra H. Josephs, Simon J. Crabb, John Staffurth, Anjali Zarkar, Laura White, Marian Duggan, Giulia Pellizzari, Graham Wheeler, Sandy Beare, Hayley Cartwright, Josep Linares, Ayse Akarca, Sergio A. Quezada, Leah Ensell, John Hartley, Gerhardt Attard, Joanna Burr, Anuradha Jayaram, Bihani Kularatne, Mahaz Kayani, Moon Chung, Colin C. Pritchard, Alex Freeman, Aiman Haider, Teresa Marafioti. Nivolumab (NIVO) and ipilimumab (IPI) treatment in prostate cancer with an immunogenic signature: cohort 1 of the NEPTUNES multi-centre, two-stage biomarker-selected Phase II trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB004.

Systemic pro-inflammatory response identifies patients with cancer with adverse outcomes from SARS-CoV-2 infection: the OnCovid Inflammatory Score

BACKGROUND

Patients with cancer are particularly susceptible to SARS-CoV-2 infection. The systemic inflammatory response is a pathogenic mechanism shared by cancer progression and COVID-19. We investigated systemic inflammation as a driver of severity and mortality from COVID-19, evaluating the prognostic role of commonly used inflammatory indices in SARS-CoV-2-infected patients with cancer accrued to the OnCovid study.

METHODS

In a multicenter cohort of SARS-CoV-2-infected patients with cancer in Europe, we evaluated dynamic changes in neutrophil:lymphocyte ratio (NLR); platelet:lymphocyte ratio (PLR); Prognostic Nutritional Index (PNI), renamed the OnCovid Inflammatory Score (OIS); modified Glasgow Prognostic Score (mGPS); and Prognostic Index (PI) in relation to oncological and COVID-19 infection features, testing their prognostic potential in independent training (n=529) and validation (n=542) sets.

RESULTS

We evaluated 1071 eligible patients, of which 625 (58.3%) were men, and 420 were patients with malignancy in advanced stage (39.2%), most commonly genitourinary (n=216, 20.2%). 844 (78.8%) had ≥1 comorbidity and 754 (70.4%) had ≥1 COVID-19 complication. NLR, OIS, and mGPS worsened at COVID-19 diagnosis compared with pre-COVID-19 measurement (p<0.01), recovering in survivors to pre-COVID-19 levels. Patients in poorer risk categories for each index except the PLR exhibited higher mortality rates (p<0.001) and shorter median overall survival in the training and validation sets (p<0.01). Multivariable analyses revealed the OIS to be most independently predictive of survival (validation set HR 2.48, 95% CI 1.47 to 4.20, p=0.001; adjusted concordance index score 0.611).

CONCLUSIONS

Systemic inflammation is a validated prognostic domain in SARS-CoV-2-infected patients with cancer and can be used as a bedside predictor of adverse outcome. Lymphocytopenia and hypoalbuminemia as computed by the OIS are independently predictive of severe COVID-19, supporting their use for risk stratification. Reversal of the COVID-19-induced proinflammatory state is a putative therapeutic strategy in patients with cancer.

Cancer History and Systemic Anti-Cancer Therapy Independently Predict COVID-19 Mortality: A UK Tertiary Hospital Experience

BACKGROUND

The COVID-19 pandemic remains a pressing concern to patients with cancer as countries enter the second peak of the pandemic and beyond. It remains unclear whether cancer and its treatment contribute an independent risk for mortality in COVID-19.

METHODS

We included patients at a London tertiary hospital with laboratory confirmed SARS-CoV-2 infection. All patients with a history of solid cancer were included. Age- and sex-matched patients without cancer were randomly selected. Patients with hematological malignancies were excluded.

RESULTS

We identified 94 patients with cancer, matched to 226 patients without cancer. After adjusting for age, ethnicity, and co-morbidities, patients with cancer had increased mortality following COVID-19 (HR 1.57, 95% CI:1.04-2.4, p = 0.03). Increasing age (HR 1.49 every 10 years, 95% CI:1.25-1.8, p < 0.001), South Asian ethnicity (HR 2.92, 95% CI:1.73-4.9, p < 0.001), and cerebrovascular disease (HR 1.93, 95% CI:1.18-3.2, p = 0.008) also predicted mortality. Within the cancer cohort, systemic anti-cancer therapy (SACT) within 60 days of COVID-19 diagnosis was an independent risk factor for mortality (HR 2.30, 95% CI: 1.16-4.6, p = 0.02).

CONCLUSIONS

Along with known risk factors, cancer and SACT confer an independent risk for mortality following COVID-19. Further studies are needed to understand the socio-economic influences and pathophysiology of these associations.

Clinical portrait of the SARS-CoV-2 epidemic in European cancer patients

The SARS-Cov-2 pandemic significantly impacted on oncology practice across the globe. There is uncertainty as to the contribution of patients' demographics and oncological features on severity and mortality from Covid-19 and little guidance as to the role of anti-cancer and anti-Covid-19 therapy in this population. In a multi-center study of 890 cancer patients with confirmed Covid-19 we demonstrated a worsening gradient of mortality from breast cancer to haematological malignancies and showed that male gender, older age, and number of co-morbidities identifies a subset of patients with significantly worse mortality rates from Covid-19. Provision of chemotherapy, targeted therapy and immunotherapy did not worsen mortality. Exposure to antimalarials was associated with improved mortality rates independent of baseline prognostic factors. This study highlights the clinical utility of demographic factors for individualized risk-stratification of patients and support further research into emerging anti-Covid-19 therapeutics in SARS-Cov-2 infected cancer patients.

Escape from nonsense-mediated decay associates with anti-tumor immunogenicity

Frameshift insertion/deletions (fs-indels) are an infrequent but highly immunogenic mutation subtype. Although fs-indels are degraded through the nonsense-mediated decay (NMD) pathway, we hypothesise that some fs-indels escape degradation and elicit anti-tumor immune responses. Using allele-specific expression analysis, expressed fs-indels are enriched in genomic positions predicted to escape NMD, and associated with higher protein expression, consistent with degradation escape (NMD-escape). Across four independent melanoma cohorts, NMD-escape mutations are significantly associated with clinical-benefit to checkpoint inhibitor (CPI) therapy (Pmeta = 0.0039). NMD-escape mutations are additionally found to associate with clinical-benefit in the low-TMB setting. Furthermore, in an adoptive cell therapy treated melanoma cohort, NMD-escape mutation count is the most significant biomarker associated with clinical-benefit. Analysis of functional T cell reactivity screens from personalized vaccine studies shows direct evidence of fs-indel derived neoantigens eliciting immune response, particularly those with highly elongated neo open reading frames. NMD-escape fs-indels represent an attractive target for biomarker optimisation and immunotherapy design.

Presenting Features and Early Mortality from SARS-CoV-2 Infection in Cancer Patients during the Initial Stage of the COVID-19 Pandemic in Europe

We describe the outcomes in cancer patients during the initial outbreak of the COVID-19 in Europe from the retrospective, multi-center observational OnCovid study. We identified 204 cancer patients from eight centers in the United Kingdom, Italy, and Spain aged > 18 (mean = 69) and diagnosed with COVID-19 between February 26th and April 1st, 2020. A total of 127 (62%) were male, 184 (91%) had a diagnosis of solid malignancy, and 103 (51%) had non-metastatic disease. A total of 161 (79%) had > 1 co-morbidity. A total of 141 (69%) patients had > 1 COVID-19 complication. A total of 36 (19%) were escalated to high-dependency or intensive care. A total of 59 (29%) died, 53 (26%) were discharged, and 92 (45%) were in-hospital survivors. Mortality was higher in patients aged > 65 (36% versus 16%), in those with > 2 co-morbidities (40% versus 18%) and developing > 1 complication from COVID-19 (38% versus 4%, p = 0.004). Multi-variable analyses confirmed age > 65 and > 2 co-morbidities to predict for patient mortality independent of tumor stage, active malignancy, or anticancer therapy. During the early outbreak of SARS-CoV-2 infection in Europe co-morbid burden and advancing age predicted for adverse disease course in cancer patients. The ongoing OnCovid study will allow us to compare risks and outcomes in cancer patients between the initial and later stages of the COVID-19 pandemic.

Publisher Correction: Spatial heterogeneity of the T cell receptor repertoire reflects the mutational landscape in lung cancer

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Intratumoural (IT) evolutionary landscape of high-risk prostate cancer and outcome: The PROGENY (PROstate cancer GENomic heterogeneitY) study of genomic and immune parameters

e17500

Background: IT heterogeneity (ITH) is well recognised in prostate cancer (PC), but its role in high-risk disease and patient outcomes are uncertain. Methods: This was a prospective, single-arm, translational study using targeted multi-region prostate biopsies to study genomic and T-cell ITH in clinically high-risk PC aiming to identify drivers and potential therapeutic strategies. A pre-defined exploratory objective was to evaluate the association of ITH, median inflammatory infiltrate (MII), total, clonal and neoantigens, with overall survival (OS) and time-to-next-line of therapy (TTNL). Results: 49 men with elevated prostate-specific antigen (PSA) and multiparametric-magnetic resonance imaging (MRI) detected PC underwent image-guided multiregion transperineal biopsy. 79 tumour regions from 25 patients (pts) with PC underwent sequencing, analysis of mutations, copy number and neoepitopes combined with tumour infiltrating T-cell subset quantification. The median follow-up was 60 months (m) with 10 death events. For %ITH, MII, total, clonal and subclonal neoantigens, patients were split by the median. Conclusions: The PROGENY study provides a diagnostic platform suitable for studying tumour ITH and has the potential to identify poor outcome subgroups in PC. Larger sample numbers in prospective trials are warranted to further investigate this hypothesis. [Table: see text]

The T cell differentiation landscape is shaped by tumour mutations in lung cancer

Tumour mutational burden (TMB) predicts immunotherapy outcome in non-small cell lung cancer (NSCLC), consistent with immune recognition of tumour neoantigens. However, persistent antigen exposure is detrimental for T cell function. How TMB affects CD4 and CD8 T cell differentiation in untreated tumours, and whether this affects patient outcomes is unknown. Here we paired high-dimensional flow cytometry, exome, single-cell and bulk RNA sequencing from patients with resected, untreated NSCLC to examine these relationships. TMB was associated with compartment-wide T cell differentiation skewing, characterized by loss of TCF7-expressing progenitor-like CD4 T cells, and an increased abundance of dysfunctional CD8 and CD4 T cell subsets, with significant phenotypic and transcriptional similarity to neoantigen-reactive CD8 T cells. A gene signature of redistribution from progenitor-like to dysfunctional states associated with poor survival in lung and other cancer cohorts. Single-cell characterization of these populations informs potential strategies for therapeutic manipulation in NSCLC.

Spatial heterogeneity of the T cell receptor repertoire reflects the mutational landscape in lung cancer

Somatic mutations together with immunoediting drive extensive heterogeneity within non-small-cell lung cancer (NSCLC). Herein we examine heterogeneity of the T cell antigen receptor (TCR) repertoire. The number of TCR sequences selectively expanded in tumors varies within and between tumors and correlates with the number of nonsynonymous mutations. Expanded TCRs can be subdivided into TCRs found in all tumor regions (ubiquitous) and those present in a subset of regions (regional). The number of ubiquitous and regional TCRs correlates with the number of ubiquitous and regional nonsynonymous mutations, respectively. Expanded TCRs form part of clusters of TCRs of similar sequence, suggestive of a spatially constrained antigen-driven process. CD8+ tumor-infiltrating lymphocytes harboring ubiquitous TCRs display a dysfunctional tissue-resident phenotype. Ubiquitous TCRs are preferentially detected in the blood at the time of tumor resection as compared to routine follow-up. These findings highlight a noninvasive method to identify and track relevant tumor-reactive TCRs for use in adoptive T cell immunotherapy.

Nivolumab and ipilimumab treatment in prostate cancer with an immunogenic signature (NEPTUNES)

TPS5090

Background: Responses to checkpoint inhibitor (CPI) monotherapy in patients with metastatic castration resistant prostate cancer (mCRPC) have been limited. This is in part attributed to low tumour mutational burden (TMB) and low tumour infiltrating lymphocytes (TILs). Previously ~20% patients with prostate cancer have demonstrated high TILs or TMB1. We hypothesize that patients with higher TMB due to mismatch repair deficiency (dMMR) or defective DNA damage response (dDDR) and patients with high TILs are more likely to respond to combination CPI with anti PD-1 and anti CTLA-4 therapy. Methods: NEPTUNES is a single arm phase II trial designed to assess the efficacy of nivolumab and ipilimumab in biomarker selected patients with mCRPC that have progressed following ≥1 line of therapy. The immunogenic signature (ImS) biomarker is defined by ≥1 of the following: 1) dMMR by immunohistochemistry (IHC); 2) dDDR detected by the UW-OncoPlex sequencing assay and; 3) high TILs on multiplexed IHC. The UW-OncoPlex assay detects mutations in >260 genes and provides an estimation of TMB. Assuming an ImS+ rate of 20%, we aim to pre-screen 175 patients in order to enrol 35 patients into the main study. The primary endpoint is composite response rate (CRR), achieved if ≥1 of the following criteria are satisfied: 1) radiological response by RECIST 1.1; 2) PSA response ≥50%; 3) conversion of circulating tumour cells (CTC) count from ≥5 cells at baseline to <5 cells at week 9. The treatment will be deemed ineffective if the CRR is <20%. Nivolumab (1 mg/kg) and ipilimumab (3 mg/kg) is dosed every three weeks for up to 4 times, followed by a 480mg flat dose of nivolumab every 4 weeks for up to one year. Baseline biopsies are mandated and paired biopsy at week 12 is encouraged. The secondary endpoints include safety, overall survival, and radiological and PSA progression free survival. Exploratory biological markers including TMB, mutational profiles, change in TILs and liquid biomarkers will be correlated with the primary clinical endpoint. Since opening in February 2018, 126 patients have been pre-screened with 25 ImS+. To date, 9/25 ImS+ patients have been enrolled into the main study. The trial is ongoing, with patient accrual expected to complete by late 2019. References: 1Linch, M., Goh, G., Hiley, C., Shanmugabavan, Y., McGranahan, N., Rowan, A., . . . Swanton, C. (2017). Intratumoural evolutionary landscape of high-risk prostate cancer: the PROGENY study of genomic and immune parameters. Ann Oncol, 28(10), 2472-2480. doi:10.1093/annonc/mdx355. Clinical trial information: NCT03061539.

Urine-derived lymphocytes as a non-invasive measure of the bladder tumor immune microenvironment

Despite the advances in cancer immunotherapy, only a fraction of patients with bladder cancer exhibit responses to checkpoint blockade, highlighting a need to better understand drug resistance and identify rational immunotherapy combinations. However, accessibility to the tumor prior and during therapy is a major limitation in understanding the immune tumor microenvironment (TME). Herein, we identified urine-derived lymphocytes (UDLs) as a readily accessible source of T cells in 32 patients with muscle invasive bladder cancer (MIBC). We observed that effector CD8+ and CD4+ cells and regulatory T cells within the urine accurately map the immune checkpoint landscape and T cell receptor repertoire of the TME. Finally, an increased UDL count, specifically high expression of PD-1 (PD-1hi) on CD8+ at the time of cystectomy, was associated with a shorter recurrence-free survival. UDL analysis represents a dynamic liquid biopsy that is representative of the bladder immune TME that may be used to identify actionable immuno-oncology (IO) targets with potential prognostic value in MIBC.

Fc Effector Function Contributes to the Activity of Human Anti-CTLA-4 Antibodies

With the use of a mouse model expressing human Fc-gamma receptors (FcγRs), we demonstrated that antibodies with isotypes equivalent to ipilimumab and tremelimumab mediate intra-tumoral regulatory T (Treg) cell depletion in vivo, increasing the CD8+ to Treg cell ratio and promoting tumor rejection. Antibodies with improved FcγR binding profiles drove superior anti-tumor responses and survival. In patients with advanced melanoma, response to ipilimumab was associated with the CD16a-V158F high affinity polymorphism. Such activity only appeared relevant in the context of inflamed tumors, explaining the modest response rates observed in the clinical setting. Our data suggest that the activity of anti-CTLA-4 in inflamed tumors may be improved through enhancement of FcγR binding, whereas poorly infiltrated tumors will likely require combination approaches.

Intratumoural evolutionary landscape of high-risk prostate cancer: the PROGENY study of genomic and immune parameters

BACKGROUND

Intratumoural heterogeneity (ITH) is well recognised in prostate cancer (PC), but its role in high-risk disease is uncertain. A prospective, single-arm, translational study using targeted multiregion prostate biopsies was carried out to study genomic and T-cell ITH in clinically high-risk PC aiming to identify drivers and potential therapeutic strategies.

PATIENTS AND METHODS

Forty-nine men with elevated prostate-specific antigen and multiparametric-magnetic resonance imaging detected PC underwent image-guided multiregion transperineal biopsy. Seventy-nine tumour regions from 25 patients with PC underwent sequencing, analysis of mutations, copy number and neoepitopes combined with tumour infiltrating T-cell subset quantification.

RESULTS

We demonstrated extensive somatic nucleotide variation and somatic copy number alteration heterogeneity in high-risk PC. Overall, the mutational burden was low (0.93/Megabase), but two patients had hypermutation, with loss of mismatch repair (MMR) proteins, MSH2 and MSH6. Somatic copy number alteration burden was higher in patients with metastatic hormone-naive PC (mHNPC) than in those with high-risk localised PC (hrlPC), independent of Gleason grade. Mutations were rarely ubiquitous and mutational frequencies were similar for mHNPC and hrlPC patients. Enrichment of focal 3q26.2 and 3q21.3, regions containing putative metastasis drivers, was seen in mHNPC patients. We found evidence of parallel evolution with three separate clones containing activating mutations of β-catenin in a single patient. We demonstrated extensive intratumoural and intertumoural T-cell heterogeneity and high inflammatory infiltrate in the MMR-deficient (MMRD) patients and the patient with parallel evolution of β-catenin. Analysis of all patients with activating Wnt/β-catenin mutations demonstrated a low CD8+/FOXP3+ ratio, a potential surrogate marker of immune evasion.

CONCLUSIONS

The PROGENY (PROstate cancer GENomic heterogeneitY) study provides a diagnostic platform suitable for studying tumour ITH. Genetic aberrations in clinically high-risk PC are associated with altered patterns of immune infiltrate in tumours. Activating mutations of Wnt/β-catenin signalling pathway or MMRD could be considered as potential biomarkers for immunomodulation therapies.

CLINICAL TRIALS.GOV IDENTIFIER

NCT02022371.

Evolving adoptive cellular therapies in urological malignancies

Immunotherapies have long been used to treat urological cancers but rarely lead to cure. In the past 5 years, success of immune checkpoint inhibition has led to a resurgence of enthusiasm for immunotherapy in the treatment of solid tumours. Increased understanding of tumour immune biology, technological advancements of gene transfer and cell culture, and improved clinical infrastructures for routine delivery of cell products, has made cell-based immunotherapeutics a real prospect for cancer therapy. These scientific and clinical activities, attempting to exploit the innate and adaptive immune systems for therapeutic gain, are well exemplified by the urological malignancies of renal, bladder, prostate, and penile cancer, a group of anatomically localised diseases, each with a distinct biology and different immunotherapeutic challenges. In this Review, we present the results of clinical studies investigating autologous cellular therapies in urological malignancies. Specifically, we discuss the rationale for upcoming studies, and how novel therapies and adoptive cell combinations can be used for personalised cancer therapy.

Fc-Optimized Anti-CD25 Depletes Tumor-Infiltrating Regulatory T Cells and Synergizes with PD-1 Blockade to Eradicate Established Tumors

CD25 is expressed at high levels on regulatory T (Treg) cells and was initially proposed as a target for cancer immunotherapy. However, anti-CD25 antibodies have displayed limited activity against established tumors. We demonstrated that CD25 expression is largely restricted to tumor-infiltrating Treg cells in mice and humans. While existing anti-CD25 antibodies were observed to deplete Treg cells in the periphery, upregulation of the inhibitory Fc gamma receptor (FcγR) IIb at the tumor site prevented intra-tumoral Treg cell depletion, which may underlie the lack of anti-tumor activity previously observed in pre-clinical models. Use of an anti-CD25 antibody with enhanced binding to activating FcγRs led to effective depletion of tumor-infiltrating Treg cells, increased effector to Treg cell ratios, and improved control of established tumors. Combination with anti-programmed cell death protein-1 antibodies promoted complete tumor rejection, demonstrating the relevance of CD25 as a therapeutic target and promising substrate for future combination approaches in immune-oncology.

Mammography casting-type calcification and risk of local recurrence in DCIS: analyses from a randomised study

BACKGROUND

We studied the association between mammographic calcifications and local recurrence in the ipsilateral breast.

METHODS

Case-cohort study within a randomised trial of radiotherapy in breast conservation for ductal cancer in situ of the breast (SweDCIS). We studied mammograms from cases with an ipsilateral breast event (IBE) and from a subcohort randomly sampled at baseline. Lesions were classified as a density without calcifications, architectural distortion, powdery, crushed stone-like or casting-type calcifications.

RESULTS

Calcifications representing necrosis were found predominantly in younger women. Women with crushed stone or casting-type microcalcifications had higher histopathological grade and more extensive disease. The relative risk (RR) of a new IBE comparing those with casting-type calcifications to those without calcifications was 2.10 (95% confidence interval (CI) 0.92-4.80). This risk was confined to in situ recurrences; the RR of an IBE associated with casting-type calcifications on the mammogram adjusted for age and disease extent was 16.4 (95% CI 2.20-140).

CONCLUSION

Mammographic appearance of ductal carcinoma in situ of the breast is prognostic for the risk of an in situ IBE and may also be an indicator of responsiveness to RT in younger women.