Despite its aggressive nature, triple-negative breast cancer (TNBC) often exhibits leucocyte infiltrations that correlate with favorable prognosis. In this study, we offer an explanation for this ...apparent conundrum by defining TNBC cell subsets that overexpress the IL15 immune receptor IL15RA. This receptor usually forms a heterotrimer with the IL2 receptors IL2RB and IL2RG, which regulates the proliferation and differentiation of cytotoxic T cells and NK cells. However, unlike IL15RA, the IL2RB and IL2RG receptors are not upregulated in basal-like TNBC breast cancer cells that express IL15RA. Mechanistic investigations indicated that IL15RA signaling activated JAK1, STAT1, STAT2, AKT, PRAS40, and ERK1/2 in the absence of IL2RB and IL2RG, whereas neither STAT5 nor JAK2 were activated. RNAi-mediated attenuation of IL15RA established its role in cell growth, apoptosis, and migration, whereas expression of the IL15 cytokine in IL15RA-expressing cells stimulated an autocrine signaling cascade that promoted cell proliferation and migration and blocked apoptosis. Notably, coexpression of IL15RA and IL15 was also sufficient to activate peripheral blood mononuclear cells upon coculture in a paracrine signaling manner. Overall, our findings offer a mechanistic explanation for the paradoxical association of some high-grade breast tumors with better survival outcomes, due to engagement of the immune stroma.
Mortality of patients with breast cancer is due overwhelmingly to metastatic spread of the disease. Although dissemination is an early event in breast cancer, extended periods of cancer cell dormancy ...can result in long latency of metastasis development. Deciphering the mechanisms underlying cancer cell dormancy and subsequent growth at the metastatic site would facilitate development of strategies to interfere with these processes. A challenge in this undertaking has been the lack of models for cancer cell dormancy. We have established novel experimental systems that model the bone microenvironment of the breast cancer metastatic niche. These systems are based on 3D cocultures of breast cancer cells with cell types predominant in bone marrow. We identified conditions in which cancer cells are dormant and conditions in which they proliferate. Dormant cancer cells were able to proliferate upon transfer into supportive microenvironment or upon manipulation of signaling pathways that control dormancy. These experimental systems will be instrumental for metastasis studies, particularly the study of cellular dormancy.
The identification of cells responsible for metastasis and their routes of dissemination is critical for understanding the characteristics that engender metastatic potential.DNA sequencing of primary ...tumours and metastases from the same patient enables the reconstruction of the evolutionary steps of metastasis, but the accuracy of this strategy is reliant on comprehensive sampling of both.Research autopsy studies overcome the limitations of tissue sampling in living patients, thereby providing the detailed view of the metastatic landscape needed to inform an understanding of the biological underpinnings of metastasis and approaches to prevent its onset.
Metastasis is a complex process and the leading cause of cancer-related death globally. Recent studies have demonstrated that genomic sequencing data from paired primary and metastatic tumours can be used to trace the evolutionary origins of cells responsible for metastasis. This approach has yielded new insights into the genomic alterations that engender metastatic potential, and the mechanisms by which cancer spreads. Given that the reliability of these approaches is contingent upon how representative the samples are of primary and metastatic tumour heterogeneity, we review insights from studies that have reconstructed the evolution of metastasis within the context of their cohorts and designs. We discuss the role of research autopsies in achieving the comprehensive sampling necessary to advance the current understanding of metastasis.
Abstract
Introduction: Studies of cancer evolution have relied on archival tissue surplus to diagnostic requirements from living patients obtained in early stage disease and less commonly ...relapsed/metastatic disease. PEACE (Posthumous Evaluation of Advanced Cancer Environment) is a national research autopsy study aiming to understand the biological processes driving metastatic disease and cancer evolution.
Experimental procedures: Patients recruited into the national TRACERx (TRAcking Cancer Evolution through therapy (Rx)) lung study who subsequently developed metastatic disease were enrolled into PEACE. Here we present a cohort of 15 TRACERx/PEACE patients in whom multi-region tumor sampling was performed at diagnosis +/- relapse and at autopsy. Fresh frozen tissue was subjected to whole-exome sequencing (mean depth 390) and germline DNA from blood was used for reference. Single nucleotide variants (SNVs) were identified using VarScan2 and the subclonal composition of each tumor was inferred using PyClone and used to reconstruct phylogenetic trees.
Summary of data: Disease progression was associated with increased genomic complexity. Different patterns of progression occurred; monoclonal/monophyletic, polyclonal/monophyletic and polyclonal/polyphyletic dissemination. Both early and late divergence relative to the last clonal sweep were observed. Putative drivers were found to occur both clonally and subclonally. SNVs and copy number aberrations were used to reconstruct migration patterns.
Conclusions: Preliminary analysis in this cohort demonstrates increasing genomic complexity with disease progression and variation in patterns of metastatic dissemination. We are yet to establish the impact of the tumor and immune microenvironment on such patterns as well as clinical presentation and outcome. Ongoing PEACE analysis includes study of the somatic copy number landscape and the characterisation of subclones that seed metastases.
Patient & sample characteristicsN (%)Total patients15Median age (IQR)73 (65 - 80)Female sex (%)6 (40%)Histological subtypeAdenocarcinoma7 (47%)Squamous cell carcinoma5 (33%)Large cell carcinoma2 (13%)Adenosquamous carcinoma1 (7%)Treatment receivedRadiotherapy8 (53%)Chemotherapy6 (40%)Immunotherapy5 (33%)Targeted therapy4 (27%)Smoking statusCurrent smoker2 (13%)Ex-smoker12 (80%)Never smoker1 (7%)Total metastases sampled289Median samples per patient (range)19 (5 - 41)Number of samples per patient5-104 (27%)11-205 (33%)>206 (40%)Number of tissue types sampled17
Citation Format: Ariana Huebner, Sonya Hessey, Cristina Naceur-Lombardelli, Mita Akther, Selvaraju Veeriah, Maise Al Bakir, David Moore, Simone Zaccaria, Nicholas McGranahan, Charles Swanton, Mariam Jamal-Hanjani, TRACERx and PEACE consortium. Lung cancer evolutionary trajectories in PEACE 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 3123.
Abstract Non-small cell lung cancer (NSCLC) is a highly complex disease, characterized by extensive genomic heterogeneity and dynamic evolution under therapeutic pressure. This evolution can lead to ...alterations in the antigens expressed by cancer cells, thereby influencing the T cell repertoire (TCR) as T cells expand in response to foreign antigens. Despite the central role of TCR in cancer progression and treatment response, only few studies have investigated the temporal and spatial changes in the TCR repertoire. In this study, we delve into the role of the TCR repertoire in metastatic progression in NSCLC. We conducted TCR sequencing of multiregion primary tumors, normal-adjacent tissues, and post-mortem metastases sampled from a cohort of 22 patients enrolled in the TRACERx and PEACE studies. Our findings reveal that primary tumor regions and normal-adjacent tissues exhibit similar fractions of expanded clonotypes. However, a higher proportion of expanded intratumoral TCRs were privately expanded in the tumor samples, suggesting a unique TCR landscape within the tumor microenvironment. The TCR repertoire across multiregion primary tumor samples was largely homogenous, with most expanded clonotypes shared across at least two regions. However, only a small fraction of these clonotypes were tracked in metastases, indicating a significant shift in the TCR repertoire during metastatic progression. Notably, the expanded clonotypes that persisted over time from early to late stage disease were significantly enriched for clonotypes ubiquitously expanded in the primary tumor across all regions. This was not shown to be associated with an increased likelihood of generation via VDJ recombination, suggesting a tumor-specific immune response. The expanded TCR repertoire in the postmortem metastases clustered mainly by anatomical site, suggesting an immune response driven by tissue-resident T cells. Moreover, we found a significant positive correlation between repertoire dissimilarity and genomic distance, suggesting that T cell clones track with tumor clones across spatial sites within patients. Our study demonstrates the significant spatiotemporal dynamics of the TCR repertoire during the metastatic progression of NSCLC, orchestrated by both tissue-resident T cells and the genomic evolutionary trajectory of tumors. Such an exploration could provide valuable insights to inform future strategies for immunotherapy treatments and enhance clinical monitoring of patients. Citation Format: Corentin Richard, Sonya Hessey, Cristina Naceur-Lombardelli, Selvaraju Veeriah, Gayathri Nageswaran, Crispin Hiley, Sergio Quezada, Benny Chain, TRACERx and PEACE Consortia, Charles Swanton, Mariam Jamal-Hanjani. Inferring the T cell repertoire dynamics in non-small cell lung cancer metastases abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1609.
Abstract Metastatic lung cancer is a heterogeneous disease, characterized by different patterns of clinical progression and therapy response. The scale of this heterogeneity on a lesion specific ...level has yet to be quantified but is of clinical importance because it may provide an indication of molecular mechanisms underpinning metastasis growth. Currently, whether metastasis growth patterns can be predicted by the primary tumor or governed by metastasis specific characteristics is not known. Furthermore, circulating tumor DNA (ctDNA) has proven useful to predict disease relapse, but how closely it reflects metastatic growth post relapse is unclear. In 104 patients enrolled in the TRACERx study with disease relapse post-surgical resection of the primary tumor, lesion volumetric dynamics were tracked in 460 metastases. Total volume growth rate (TVGR) was calculated using CT imaging performed between disease relapse and death. All patients had whole exome sequencing (WES) of the primary tumor. For 19 patients enrolled in the PEACE autopsy study WES and RNAseq from 60 metastases visible on imaging prior to death and subsequently sampled at autopsy were analyses. In 29 patients, ctDNA was used to track 200 tumor-specific mutations to assess tumor burden and detect metastatic subclones. High TVGR correlated with poor survival (hazard ratio for death 1st vs 2nd tertile was 0.21, p<0.001; 2nd vs 3rd tertile was 0.51, p=0.04). Primary tumor subclonal whole genome doubling was predictive of high TVGR. There was considerable heterogeneity in the growth rate of metastases within patients. The anatomical location of metastases contributed to this, extrathoracic soft tissue and pleura had the highest growth rates, whilst lymph node and adrenal the lowest (p<0.001). Molecular attributes differed between metastases, with fast growing metastases being enriched for proliferation pathway gene expression. It was observed that the most prevalent population of cells, or clone, in the fastest growing metastasis within a patient was exclusive to that metastasis, suggesting that genomic features that characterize the clone might support rapid growth. ctDNA tracked with tumor burden post relapse and patients with extrathoracic relapse had higher levels of ctDNA. In 9 patients, metastasis specific mutations identified at autopsy and in ctDNA, were used to determine the proportion of ctDNA shed by different metastatic sites. ctDNA subclonal fraction was found to track with changes in lesion volumes during disease progression. This work highlights significant heterogeneity in metastatic growth rates which can potentially be attributed to the presence of distinct genomic features which may dictate tumor growth rate. ctDNA accurately reproduces patterns of radiological disease progression and when combined with longitudinal imaging and tumor DNA sequencing, can accurately reconstruct the natural history of cancer evolution. Citation Format: Wing Kin Liu, Boyue Ding, Hessey Sonya, Carlos Martinez-Ruiz, Cristina Naceur-Lombardelli, Corentin Richard, Hyothaek Lee, Catarina Veiga, Kishen Patel, Ariana Huebner, Allan Hackshaw, Christopher Abbosh, Alexander M. Frankell, Gary Royle, Charles Swanton, Mariam Jamal-Hanjani. Tracking metastatic dissemination and tumor growth using longitudinal imaging and ctDNA abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4136.
Abstract Background: Cancer research autopsy genomic studies offer insight into the metastatic cancer landscape but come with complexities that relate to the sampling and processing of post-mortem ...tissue. Clarifying the effect of autopsy variables on pre- and post-sequencing quality control (QC) is an unmet need that may inform tissue collection strategies. Methods: The effect of age, sex, post-mortem interval (PMI), and sample type (primary, metastatic, or normal) on pre-sequencing QC (nucleic acid concentration and integrity) was examined in 2678 samples (88.6% metastatic, 8.0% primary, 3.4% normal) from 83 patients with melanoma, lung, renal, or prostate cancer in the PEACE study. In the lung cohort, 160 surgical samples were also included through the TRACERx study, allowing surgery-autopsy tissue comparisons. Post-sequencing QC metrics were evaluated for lung samples that underwent DNA (n=522) or RNA (n=366) sequencing. Results: RNA concentration and RIN were greater in surgical samples than those collected at autopsy. Across cohorts, metastatic autopsy samples had greater nucleic acid concentrations than primary or normal autopsy samples, but not integrity. DNA and RNA concentration and integrity differed significantly between primary tumor types. When comparing samples of different metastatic sites from the whole cohort, concentration was lowest in bone (DNA) or the digestive tract (RNA), while integrity was greatest in the brain and lowest in the digestive tract (DIN, RIN). Although autopsy variables like age, sex and PMI correlated with pre-sequencing QC metrics in univariate analysis, they were not found to significantly correlate with these metrics in multivariate analysis, which identified that only primary cancer type and metastatic site were independent determinants of concentration and integrity. Similarly, for post-DNA (whole exome) sequencing QC, only the metastatic site was found to independently influence sequencing QC metrics like total number of sequences, average sequence length, and FastQC score. For RNA sequencing, only the metastatic site was found to influence sequencing QC metrics like total number of sequences, percentage of non-duplicated sequences, one hit-one genome percentage, and the alignment percentage on the human genome. Discussion: The lack of influence of PMI on QC in the largest QC-focused autopsy cancer study to date suggests that quality tissue can be obtained from non-rapid autopsy programs, which are more feasible and less resource-intensive than rapid programs. Citation Format: Petros Fessas, Sonya Hessey, Corentin Richard, Cristina Naceur-Lombardelli, Sophia Ward, David A. Moore, Karolina Nowakowska, Blanca Trujillo, Irene Lobon, Scott T. Shepherd, Fiona Byrne, Samra Turajlic, Gerhardt Attard, Charles Swanton, Mariam Jamal-Hanjani. The effect of cancer research autopsy parameters on DNA and RNA sequencing quality abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2926.
Abstract
Metastatic non-small cell lung cancer (NSCLC) results from a complex evolutionary process in which cancer cells migrate from a primary tumour to a new anatomical site. Immunotherapy is ...frequently used to treat NSCLC, but drug resistance is frequent (>50%) and metastasis remains the most common cause of death. Recent studies of primary and metastatic tumours suggest that anti-cancer treatments can impact cancer evolutionary dynamics by applying selective pressures that promote the development of treatment resistance in genetically distinct subpopulations of cancer cells, or tumour clones. However, the relationship between metastatic progression and the development of resistance to immunotherapy has not been fully explored. In particular, whether metastases become resistant to immunotherapy as a result of the migration of resistant cells or whether distinct metastatic sites converge in parallel toward an immunotherapy resistance phenotype irrespective of cell migration, is not known.
In this work, we investigate the role of metastatic cell migration in the development of immunotherapy resistance using DNA sequencing data from primary and metastatic tumour samples from twelve immunotherapy-treated patients with NSCLC co-recruited to the national TRACERx and PEACE studies. Using computational approaches, we identified distinct tumour clones in primary and metastatic tumours and used these to reconstruct tumour phylogenies for each patient. By evaluating tumour clonal dynamics in relation to treatment, we classified tumour clones as either sensitive or resistant to immunotherapy. We reconstructed the metastatic migration histories of these clones using existing computational methods based on somatic single nucleotide variants. Our results suggest that heterogeneous mechanisms of immune evasion develop in parallel at distinct metastatic sites. The ongoing analysis of the genetic changes that distinguish resistant from sensitive clones, and migrating from non-migrating clones, will provide further detail regarding the impact of metastatic migrations on immunotherapy resistance.
Using this approach to map the evolutionary history of metastatic NSCLC, we provide insight into the mechanism by which immunotherapy resistance develops at distinct metastatic sites.
Citation Format: Sonya Hessey, Ariana Huebner, Oriol Pich, Abi Bunkum, Wing Liu, David A. Moore, Cristina Naceur-Lombardelli, Selvaraju Veeriah, Sophie Ward, Roberto Salgado, Nicholas McGranahan, Simone Zaccaria, Charles Swanton, Mariam Jamal-Hanjani. Tracking the emergence of immunotherapy resistance in lung cancer metastases abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2037.