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Parameningeal Rhabdomyosarcoma: Results of the European Pediatric Soft Tissue Sarcoma Study Group RMS 2005 Study.
No full textBACKGROUND: Parameningeal (PM) site is an unfavorable characteristic in rhabdomyosarcoma (RMS). We described the treatment and outcome for patients with PM RMS and investigated the prognostic value of risk factors. We scored PM site by originating site and by highest risk extension. METHODS: Patients with PM RMS were treated within the European pediatric Soft tissue sarcoma Study Group (EpSSG) RMS 2005 study with risk-adapted, multi-modal treatment. RESULTS: Three-hundred-eighty-one patients with PM RMS were included. Radiotherapy was administered in 359 patients (77 with surgery). After a median follow-up of 75 months, 5-year event-free survival was 60% (95% confidence interval (CI) 55%-65%), 5-year overall survival was 65% (95% CI 60%-70%). CONCLUSIONS: The outcome for patients with PM RMS has not improved in comparison to previous historical studies, despite the more rigorous application of radiotherapy (94% of patients). Signs of meningeal involvement, PM site, and age at diagnosis remained prognostic risk factors. TRIAL REGISTRATION: EudraCT number 2005-000217-35
Unveiling, Analyzing the Mechanisms of, and Proposing Solutions for Bribery in Japan's Medical Device Sector.
No full textBoth public and academic scrutiny of the financial relationships between the medical device industry and the healthcare society occur less frequently than those involving the pharmaceutical industry, and Japan is no exception to these shortcomings. This paper examines the ethical and legal challenges inherent in Japan's medical device industry through the lens of bribery scandals, placing these issues within the broader context of global healthcare corruption. It aims to derive lessons and suggest universal strategies for ethical and legal enhancements. The discussion includes two notable cases: one involving inappropriate transactions between a cancer center and a biliary stent manufacturer, and another concerning a corrupt donation scheme between a medical device company and a university's anesthesiology department, which was found guilty. In our analysis, we also acknowledge the industry's efforts toward compliance and reform to maintain a balanced perspective. The analysis not only highlights the unique culture and structure of the Japanese medical device industry, such as the exploitation of flexible pricing and opaque financial practices but also contrasts these issues with the tightly regulated pharmaceutical industry. This approach reveals both sector-specific challenges and common corruption drivers, enhancing our understanding of why such scandals occur and persist. We propose ethical and compliance-focused business measures such as centralizing donation decisions, limiting the financial independence of marketing divisions, and increasing transparency, alongside adopting mandatory disclosure practices based on successful models from the United States and Europe. By emphasizing integrity and presenting diverse perspectives, this study aims to elevate ethical and legal standards in the medical device industry and improve patient health outcomes worldwide
Combination of oncolytic Maraba virus with immune checkpoint blockade overcomes therapy resistance in an immunologically cold model of advanced melanoma with dysfunctional T-cell receptor signalling.
No full textBACKGROUND: Over the past decade, cancer immunotherapies have revolutionized the treatment of melanoma; however, responses vary across patient populations. Recently, baseline tumor size has been identified as an independent prognostic factor for overall survival in patients with melanoma receiving immune checkpoint inhibitors. MG1 is a novel oncolytic agent with broad tumor tropism that has recently entered early-phase clinical trials. The aim of this study was to characterize T-cell responses in human and mouse melanoma models following MG1 treatment and to establish if features of the tumor immune microenvironment (TIME) at two distinct tumor burdens would impact the efficacy of oncolytic virotherapy. METHODS: Human three-dimensional in vitro priming assays were performed to measure antitumor and antiviral T-cell responses following MG1 infection. T-cell receptor (TCR) sequencing, T2 killing assay, and peptide recall assays were used to assess the evolution of the TCR repertoire, and measure specific T-cell responses, respectively. In vivo, subcutaneous 4434 melanomas were characterized using RNA sequencing, immunohistochemistry, and flow cytometry. The effectiveness of intratumoral MG1 was assessed in advancing 4434 tumors and the generation of antitumor and antiviral T cells measured by splenocyte recall assays. Finally, combination MG1 and programmed cell death protein-1 antibody (αPD-1) therapy was investigated in advanced 4434 tumors. RESULTS: MG1 effectively supported priming of functional cytotoxic T cells (CTLs) against tumor-associated antigens as well as virus-derived peptides, as assessed using peptide recall and T2 killing assays, respectively. TCR sequencing revealed that MG1-primed CTL comprised larger clusters of similar CDR3 amino acid sequences compared with controls. In vivo testing of MG1 demonstrated that MG1 monotherapy was highly effective at treating early disease, resulting in 90% cures; however, the efficacy of MG1 reduced as the disease burden (local tumor size) increased, and the addition of αPD-1 was required to overcome resistance in more advanced disease. Differential gene expression profiles revealed that increased tumor burden was associated with an immunologically colder TIME. Furthermore, analysis of TCR signaling in advancing tumors demonstrated a different dynamic of TCR engagement compared with smaller tumors, in particular a shift in antigen recognition by CD4+ cells, from conventional to regulatory subsets. CONCLUSION: Addition of αPD-1 to MG1 is required to overcome viral therapy resistance in immunologically 'colder' more advanced melanoma, highlighting the importance of tumor burden to different types of immunotherapy
Organelle adaptations in response to mechanical forces during tumour dissemination.
No full textCell migration plays a pivotal role in various biological processes including cancer dissemination and successful metastasis, where the role of mechanical signals is increasingly acknowledged. This review focuses on the intricate mechanisms through which cancer cells modulate their migratory strategies via organelle adaptations in response to the extracellular matrix (ECM). Specifically, the nucleus and mitochondria emerge as pivotal mediators in this process. These organelles serve as sensors, translating mechanical stimuli into rapid metabolic alterations that sustain cell migration. Importantly, prolonged exposure to such stimuli can induce transcriptional or epigenetic changes, ultimately enhancing metastatic traits. Deciphering the intricate interplay between ECM properties and organelle adaptations not only advances our understanding of cytoskeletal dynamics but also holds promise for the development of innovative anti-metastatic therapeutic strategies
Immune evasion impacts the landscape of driver genes during cancer evolution.
No full textBACKGROUND: Carcinogenesis is driven by interactions between genetic mutations and the local tumor microenvironment. Recent research has identified hundreds of cancer driver genes; however, these studies often include a mixture of different molecular subtypes and ecological niches and ignore the impact of the immune system. RESULTS: In this study, we compare the landscape of driver genes in tumors that escaped the immune system (escape +) versus those that did not (escape -). We analyze 9896 primary tumors from The Cancer Genome Atlas using the ratio of non-synonymous to synonymous mutations (dN/dS) and find 85 driver genes, including 27 and 16 novel genes, in escape - and escape + tumors, respectively. The dN/dS of driver genes in immune escaped tumors is significantly lower and closer to neutrality than in non-escaped tumors, suggesting selection buffering in driver genes fueled by immune escape. Additionally, we find that immune evasion leads to more mutated sites, a diverse array of mutational signatures and is linked to tumor prognosis. CONCLUSIONS: Our findings highlight the need for improved patient stratification to identify new therapeutic targets for cancer treatment
Therapeutic inhibition of monocyte recruitment prevents checkpoint inhibitor-induced hepatitis.
No full textBACKGROUND: Checkpoint inhibitor-induced hepatitis (CPI-hepatitis) is an emerging problem with the widening use of CPIs in cancer immunotherapy. Here, we developed a mouse model to characterize the mechanism of CPI-hepatitis and to therapeutically target key pathways driving this pathology. METHODS: C57BL/6 wild-type (WT) mice were dosed with toll-like receptor (TLR)9 agonist (TLR9-L) for hepatic priming combined with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) plus anti-programmed cell death 1 (PD-1) ("CPI") or phosphate buffered saline (PBS) control for up to 7 days. Flow cytometry, histology/immunofluorescence and messenger RNA sequencing were used to characterize liver myeloid/lymphoid subsets and inflammation. Hepatocyte damage was assessed by plasma alanine transaminase (ALT) and cytokeratin-18 (CK-18) measurements. In vivo investigations of CPI-hepatitis were carried out in Rag2-/- and Ccr2rfp/rfp transgenic mice, as well as following anti-CD4, anti-CD8 or cenicriviroc (CVC; CCR2/CCR5 antagonist) treatment. RESULTS: Co-administration of combination CPIs with TLR9-L induced liver pathology closely resembling human disease, with increased infiltration and clustering of granzyme B+perforin+CD8+ T cells and CCR2+ monocytes, 7 days post treatment. This was accompanied by apoptotic hepatocytes surrounding these clusters and elevated ALT and CK-18 plasma levels. Liver RNA sequencing identified key signaling pathways (JAK-STAT, NF-ΚB) and cytokine/chemokine networks (Ifnγ, Cxcl9, Ccl2/Ccr2) as drivers of CPI-hepatitis. Using this model, we show that CD8+ T cells mediate hepatocyte damage in experimental CPI-hepatitis. However, their liver recruitment, clustering, and cytotoxic activity is dependent on the presence of CCR2+ monocytes. The absence of hepatic monocyte recruitment in Ccr2rfp/rfp mice and CCR2 inhibition by CVC treatment in WT mice was able to prevent the development and reverse established experimental CPI-hepatitis. CONCLUSION: This newly established mouse model provides a platform for in vivo mechanistic studies of CPI-hepatitis. Using this model, we demonstrate the central role of liver infiltrating CCR2+ monocyte interaction with tissue-destructive CD8+ T cells in the pathogenesis of CPI-hepatitis and highlight CCR2 inhibition as a novel therapeutic target
Expression of tumor antigens within an oncolytic virus enhances the anti-tumor T cell response.
No full textAlthough patients benefit from immune checkpoint inhibition (ICI) therapy in a broad variety of tumors, resistance may arise from immune suppressive tumor microenvironments (TME), which is particularly true of hepatocellular carcinoma (HCC). Since oncolytic viruses (OV) can generate a highly immune-infiltrated, inflammatory TME, OVs could potentially restore ICI responsiveness via recruitment, priming, and activation of anti-tumor T cells. Here we find that on the contrary, an oncolytic vesicular stomatitis virus, expressing interferon-ß (VSV-IFNß), antagonizes the effect of anti-PD-L1 therapy in a partially anti-PD-L1-responsive model of HCC. Cytometry by Time of Flight shows that VSV-IFNß expands dominant anti-viral effector CD8 T cells with concomitant relative disappearance of anti-tumor T cell populations, which are the target of anti-PD-L1. However, by expressing a range of HCC tumor antigens within VSV, combination OV and anti-PD-L1 therapeutic benefit could be restored. Our data provide a cautionary message for the use of highly immunogenic viruses as tumor-specific immune-therapeutics by showing that dominant anti-viral T cell responses can inhibit sub-dominant anti-tumor T cell responses. However, through encoding tumor antigens within the virus, oncolytic virotherapy can generate anti-tumor T cell populations upon which immune checkpoint blockade can effectively work
LKB1 depletion-mediated epithelial-mesenchymal transition induces fibroblast activation in lung fibrosis.
No full textThe factors that determine fibrosis progression or normal tissue repair are largely unknown. We previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine signalling. Here, we report that liver kinase B1 (LKB1) inactivation in ATII cells inhibits autophagy and induces EMT as a consequence. In IPF lungs, this is caused by downregulation of CAB39L, a key subunit within the LKB1 complex. 3D co-cultures of ATII cells and MRC5 lung fibroblasts coupled with RNA sequencing (RNA-seq) confirmed that paracrine signalling between LKB1-depleted ATII cells and fibroblasts augmented myofibroblast differentiation. Together these data suggest that reduced autophagy caused by LKB1 inhibition can induce EMT in ATII cells and contribute to fibrosis via aberrant epithelial-fibroblast crosstalk
Molecular subtypes of cancer-associated fibroblasts and their regulation of the tumour microenvironment in pancreatic ductal adenocarcinoma.
No full textPancreatic Ductal Adenocarcinoma (PDAC) remains a leading cause of cancer-related deaths, with a 5-year survival rate of less than 10 % in Western countries. Transcriptomic analysis of PDAC in the last decade has unearthed molecular classifiers that has shaped our understanding of inter-tumoural heterogeneity that drives the abysmally poor survival rates associated with this disease. However, expectations that these classifiers would be able to identify targeted therapies based on molecular signatures of surgically relevant candidates unfortunately remains limited due to less than reliable biomarkers for these subtypes. Further, the presence of the highly desmoplastic stroma enriched in cancer-associated fibroblasts (CAFs) and immune cells among others, aggravates treatment options. CAFs make up a significant proportion of the stroma and were once believed to represent a homogeneous population. In the last five years, this misconception has largely been removed by the identification of CAF subtypes through partitioning around medoid (PAM) centroids and single-cell RNA sequencing (scRNA-seq). CAFs are an integral population in the pancreatic tumour microenvironment (TME) and are involved in intricate crosstalk with neoplastic and immune cells. Therefore, they serve as an attractive therapeutic target to devise strategies against PDAC.
In my first results chapter, largely through scRNA-seq analysis, I investigate CAF heterogeneity, evolution, and prognosis, and provide mechanistic insight into the role CAF subtypes play in the TME. Specifically, I demonstrate the presence of a pericyte-like CAF subtype present in adjacent normal tissue that is antagonised by myCAFs and provides a physical barrier to prevent invasion and metastasis. I also highlight the presence of three to four main CAF communities through the integration of multiple published CAF transcriptomic signatures and demonstrate the prognostic power of these CAF signatures in over 600 patient samples.
In my second results chapter, to identify hetero-cellular relationships, I uncover the variable association of CAF subtypes to cancer subtypes. Further, I demonstrate the suppression of CD8 T cells by myCAFs, the latter of which also demonstrated positive correlation with anti-inflammatory macrophages. Additionally, I evaluate the CAF subtypes in the context of hypoxia and inflammatory cell death, additional hallmarks of PDAC that our lab has shown precedence in in other cancers such as pancreatic neuroendocrine tumours. Importantly, this analysis led to the identification of myCAF subsets through both bulk sequencing data and scRNA-seq analysis. Notably, I imply that there is a myofibroblast and inflammatory spectrum on which myCAFs and iCAFs lie, and only CAFs on the extreme myofibroblast end of this spectrum display immunosuppressive features, suggesting the presence of plasticity or cell states, as opposed to terminally differentiated cell types.
I dedicate my final chapter to understanding the modulation of CAF subtypes to therapy. Specifically, I demonstrate myCAFs confer resistance to gemcitabine, which forms part of the standard of care for patients with PDAC, through the suppression of iCAFs and the cytotoxic ability of T and NKT cells. This is also associated with reduction in pro-inflammatory cDC1 cells, a dendritic cell subset. In an alternative treatment strategy, through scRNA-seq analysis and in vivo stimulation of an immune dormant murine orthotopic model using engineered cytokine therapy, I demonstrate the suppression of endothelial cells by myCAFs, implicating this subtype in reduced tumour vasculature. Given a wide range of interactions between CAF subtypes and other TME-based cell types demonstrated in this chapter and results chapter 2, I perform a comprehensive scRNA-seq ligand-receptor analysis in PDAC and validate these findings across different cancer types to identify key targets and druggable candidates
Impact of germline DNA repair gene variants on prognosis and treatment of men with advanced prostate cancer.
No full textThe clinical importance of germline variants in DNA repair genes (DRGs) is becoming increasingly recognized, but their impact on advanced prostate cancer prognosis remains unclear. A cohort of 221 newly diagnosed metastatic castration-resistant prostate cancer (mCRPC) patients were screened for pathogenic germline variants in 114 DRGs. The primary endpoint was progression-free survival (PFS) on first-line androgen signaling inhibitor (ARSI) treatment for mCRPC. Secondary endpoints were time to mCRPC progression on initial androgen deprivation therapy (ADT) and overall survival (OS). Twenty-seven patients (12.2%) carried a germline DRG variant. DRG carrier status was independently associated with shorter PFS on first-line ARSI [HR 1.72 (1.06-2.81), P = 0.029]. At initiation of ADT, DRG carrier status was independently associated with shorter progression time to mCRPC [HR 1.56, (1.02-2.39), P = 0.04] and shorter OS [HR 1.99, (1.12-3.52), P = 0.02]. Investigating the contributions of individual germline DRG variants on PFS and OS revealed CHEK2 variants to have little effect. Furthermore, prior taxane treatment was associated with worse PFS on first-line ARSI for DRG carriers excluding CHEK2 (P = 0.0001), but not for noncarriers. In conclusion, germline DRG carrier status holds independent prognostic value for predicting advanced prostate cancer patient outcomes and may potentially inform on optimal treatment sequencing already at the hormone-sensitive stage