Immune cells in the tumor microenvironment modulate cancer progression and are attractive therapeutic targets. Macrophages and T cells are key components of the microenvironment, yet their phenotypes ...and relationships in this ecosystem and to clinical outcomes are ill defined. We used mass cytometry with extensive antibody panels to perform in-depth immune profiling of samples from 73 clear cell renal cell carcinoma (ccRCC) patients and five healthy controls. In 3.5 million measured cells, we identified 17 tumor-associated macrophage phenotypes, 22 T cell phenotypes, and a distinct immune composition correlated with progression-free survival, thereby presenting an in-depth human atlas of the immune tumor microenvironment in this disease. This study revealed potential biomarkers and targets for immunotherapy development and validated tools that can be used for immune profiling of other tumor types.
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•Mass cytometry reveals the immune cell diversity of the ccRCC tumor ecosystem•PD-1+ cells display heterogeneous combinations of inhibitory receptors•CD38+CD204+CD206− tumor-associated macrophages correlate with immunosuppression•A specific immune signature is linked to shorter progression-free survival
Applying mass cytometry for high-dimensional single-cell analysis depicts an in-depth atlas of the immune microenvironment in clear cell renal cell carcinoma patients, thereby linking immune compositions with clinical features.
Atezolizumab, a humanised monoclonal antibody targeting PD-L1, is approved for locally advanced/metastatic urothelial carcinoma. SAUL evaluated atezolizumab in a broader, pretreated population, ...including patients ineligible for the pivotal IMvigor211 phase 3 trial of atezolizumab.
To determine the safety and efficacy of atezolizumab in an international real-world setting.
Between November 2016 and March 2018 (median follow-up 12.7mo), 1004 patients with locally advanced or metastatic urothelial or nonurothelial urinary tract carcinoma who experienced progression during or after one to three prior therapies for inoperable, locally advanced, or metastatic disease were enrolled. Patients with renal impairment, treated central nervous system metastases, or stable controlled autoimmune disease were eligible; 10% had Eastern Cooperative Oncology Group performance status (ECOG PS) 2 and 98% were platinum pretreated (Clinicaltrials.gov: NCT02928406).
Atezolizumab 1200mg every 3wk until progression or unacceptable toxicity.
The primary endpoint was safety. Secondary efficacy endpoints included overall survival (OS), progression-free survival (PFS), and overall response rate (ORR).
The median treatment duration was 2.8mo (range 0–19); 22% remained on treatment and 8% discontinued because of toxicity. Grade ≥3 adverse events occurred in 45% of patients. The most common grade ≥3 treatment-related adverse events were fatigue, asthenia, colitis, and hypertension (each in 1%). Median OS was 8.7mo (95% confidence interval CI 7.8–9.9). The 6-mo OS rate was 60% (95% CI 57–63%), median PFS was 2.2mo (95% CI 2.1–2.4), and the ORR was 13% (95% CI 11–16%; 3% complete responses). Among IMvigor211-like patients (excluding ECOG PS 2 and other IMvigor211 exclusion criteria), median OS was 10.0mo (95% CI 8.8–11.9) and 6-mo OS was 65% (95% CI 61–69%).
SAUL confirms the tolerability of atezolizumab in a real-world pretreated population with urinary tract carcinoma. Efficacy overall and in the IMvigor211-like subgroup is consistent with previous pivotal anti-PD-L1/PD-1 urothelial carcinoma trials. These results support the use of atezolizumab in urinary tract carcinoma, including patients with limited treatment options.
In this international study we investigated the efficacy and safety of atezolizumab treatment for advanced urinary tract cancer in a large population of pretreated patients, including those who would not normally be candidates for clinical trials. Patients tolerated the treatment well, even if they had autoimmune disease, were being treated with corticosteroids, or had disease that had spread to their brain. Life expectancy in this study for patients typical of everyday clinical practice was similar to that seen in trials that enrolled only selected fitter patients.
SAUL confirms the tolerability of atezolizumab in real-world patients with urinary tract carcinoma. Efficacy in the IMvigor211-like subgroup and the broader unselected population was consistent with previous anti-PD-L1/PD-1 pivotal trials, supporting the use of atezolizumab in these patients.
Cell surface proteins have a wide range of biological functions, and are often used as lineage-specific markers. Antibodies that recognize cell surface antigens are widely used as research tools, ...diagnostic markers, and even therapeutic agents. The ability to obtain broad cell surface protein profiles would thus be of great value in a wide range of fields. There are however currently few available methods for high-throughput analysis of large numbers of cell surface proteins. We describe here a high-throughput flow cytometry (HT-FC) platform for rapid analysis of 363 cell surface antigens. Here we demonstrate that HT-FC provides reproducible results, and use the platform to identify cell surface antigens that are influenced by common cell preparation methods. We show that multiple populations within complex samples such as primary tumors can be simultaneously analyzed by co-staining of cells with lineage-specific antibodies, allowing unprecedented depth of analysis of heterogeneous cell populations. Furthermore, standard informatics methods can be used to visualize, cluster and downsample HT-FC data to reveal novel signatures and biomarkers. We show that the cell surface profile provides sufficient molecular information to classify samples from different cancers and tissue types into biologically relevant clusters using unsupervised hierarchical clustering. Finally, we describe the identification of a candidate lineage marker and its subsequent validation. In summary, HT-FC combines the advantages of a high-throughput screen with a detection method that is sensitive, quantitative, highly reproducible, and allows in-depth analysis of heterogeneous samples. The use of commercially available antibodies means that high quality reagents are immediately available for follow-up studies. HT-FC has a wide range of applications, including biomarker discovery, molecular classification of cancers, or identification of novel lineage specific or stem cell markers.
The cancer stem cell (CSC) model proposes that tumors have a hierarchical organization in which only some cells indefinitely self-renew and thereby sustain tumor growth. In addition, the CSC model ...requires that tumor-initiating cells (TICs) be prospectively isolatable on the basis of their phenotype. Previous studies have suggested that serous ovarian cancer (SOC) conforms to the CSC model, but these used arguably nonfidelitous immortalized cell lines, cultured primary cells, or passaged xenografts as the source of tumor cells. We developed a robust assay for quantifying TICs from primary SOC. Using this assay, we find that TICs are rare when assayed in either NOD/SCID or NOD/SCID/IL2Rγâ»/â» (NSG) mice. TIC frequency (TICf) varies substantially between patients, although it is similar in primary ovarian masses and omental metastases, suggesting that TICf is an intrinsic property of ovarian tumors. CD133 marks all TICs from several primary SOC cases. However, in other cases, substantial TIC activity is found in both the CD133⺠and CD133â» fractions, whereas still other cases have exclusively CD133â» TICs. Furthermore, the TIC phenotype can change in xenografts: primary tumors in which all TICs are CD133⺠can give rise to xenografts that contain substantial numbers of CD133â» TICs. Our results highlight the need for quantitative rigor in the evaluation of TICs and for caution when using passaged xenografts for such studies. Furthermore, although our data suggest that SOC conforms to the CSC hypothesis, the heterogeneity of the TIC phenotype may complicate its clinical application.
Clear cell renal cell carcinoma (ccRCC) is a markedly heterogeneous disease in many aspects, including the tumour microenvironment. Our previous study showed the importance of the tumour ...microenvironment in ccRCC xeno-transplant success rates. In order to better understand the potential relationship between TICs and the immune microenvironment, we employed a multi-modal approach, examining RNA and protein expression (flow cytometry, immunohistochemistry).
We first examined the gene expression pattern of 18 stem/progenitor marker genes in the cancer genome atlas (TCGA) ccRCC cohort. Flow cytometry was next employed to examine lineage-specific expression levels of stem/progenitor markers and immune population makeup in six, disaggregated, primary ccRCC specimens. Immunohistochemistry was performed on a commercial ccRCC tissue microarray (TMA).
The 18 genes differed with respect to their correlation patterns with one another and to their prognostic significance. By flow cytometry, correlating expression frequency of 12 stem/progenitor markers and CD10 resulted in two clusters-one with CD10 (marker of proximal tubular differentiation), and second cluster containing mostly mesenchymal stem cell (MSC) markers, including CD146. In turn, these clusters differed with respect to their correlation with different CD45
lineage markers and their expression of immune checkpoint pathway proteins. To confirm these findings, four stem/progenitor marker expression patterns were compared with CD4, CD8 and CD20 in a ccRCC TMA which showed a number of similar trends with respect to frequency of the different tumour-infiltrating leukocytes.
Taken together, we observed heterogeneous but patterned expression levels of different stem/progenitor markers. Our results suggest a non-random relationship between their expression patterns with the immune microenvironment populations in ccRCC.
Recent advances in the arena of theranostics have necessitated a re-examining of previously established fields. The existing paradigm of therapeutic thyroid-stimulating hormone receptor (TSHR) ...targeting in the post-surgical management of differentiated thyroid cancer using levothyroxine and recombinant human thyroid-stimulating hormone (TSH) is well understood. However, in an era of personalized medicine, and with an increasing awareness of the risk profile of longstanding pharmacological hyperthyroidism, it is imperative clinicians understand the molecular basis and magnitude of benefit for individual patients. Furthermore, TSHR has been recently re-conceived as a selective target for residual metastatic thyroid cancer, with pilot data demonstrating effective targeting of nanoparticles to thyroid cancers using this receptor as a target. This review examines the evidence for TSHR signaling as an oncogenic pathway and assesses the evidence for ongoing TSHR expression in thyroid cancer metastases. Priorities for further research are highlighted.
Glioblastoma multiforme (GBM) is the most lethal adult brain cancer. Temozolomide (TMZ), the standard chemotherapeutic drug used in GBM, has limited benefit and alternate therapies are needed to ...improve GBM treatment. Nerve growth factor (NGF) and its precursor proNGF are increasingly recognized as stimulators of human tumor progression. The expression and stimulatory effect of NGF on GBM cell growth has previously been reported, but the status of proNGF in GBM is unreported. In this study, we have investigated proNGF expression and biological activity in GBM. A clinical cohort of GBM (
= 72) and low-grade glioma (
= 20) was analyzed by immunohistochemistry for proNGF and digital quantification. ProNGF expression was significantly increased in GBM compared to low grade gliomas and proNGF was also detected in patient plasma samples. ProNGF was also detected in most GBM cell lines by Western blotting. Although anti-proNGF blocking antibodies inhibited cell growth in GBM cells with methylated MGMT gene promoter, targeting proNGF could not potentiate the efficacy of TMZ. In subcutaneous xenograft of human GBM cells, anti-proNGF antibodies slightly reduced tumor volume but had no impact on TMZ efficacy. In conclusion, this data reveals that proNGF is overexpressed in GBM and can stimulate cancer cell growth. The potential of proNGF as a clinical biomarker and therapeutic target warrants further investigations.
Cannabis has been used to relieve the symptoms of disease for thousands of years. However, social and political biases have limited effective interrogation of the potential benefits of cannabis and ...polarised public opinion. Further, the medicinal and clinical utility of cannabis is limited by the psychotropic side effects of ∆
-tetrahydrocannabinol (∆
-THC). Evidence is emerging for the therapeutic benefits of cannabis in the treatment of neurological and neurodegenerative diseases, with potential efficacy as an analgesic and antiemetic for the management of cancer-related pain and treatment-related nausea and vomiting, respectively. An increasing number of preclinical studies have established that ∆
-THC can inhibit the growth and proliferation of cancerous cells through the modulation of cannabinoid receptors (CB1R and CB2R), but clinical confirmation remains lacking. In parallel, the anti-cancer properties of non-THC cannabinoids, such as cannabidiol (CBD), are linked to the modulation of non-CB1R/CB2R G-protein-coupled receptors, neurotransmitter receptors, and ligand-regulated transcription factors, which together modulate oncogenic signalling and redox homeostasis. Additional evidence has also demonstrated the anti-inflammatory properties of cannabinoids, and this may prove relevant in the context of peritumoural oedema and the tumour immune microenvironment. This review aims to document the emerging mechanisms of anti-cancer actions of non-THC cannabinoids.
Oesophageal and gastrooesophageal junction (GOJ) carcinoma frequently present with dysphagia and de novo metastatic disease. There is scope to improve treatment paradigms to both address symptoms and ...improve survival. One method is integrating immune checkpoint inhibition with novel treatment combinations.
PALEO is a single arm, phase II clinical trial in patients with previously untreated, oligometastatic or locoregionally advanced oesophageal or GOJ carcinoma and dysphagia. PALEO is sponsored by the Australasian Gastro-Intestinal Trials Group (AGITG). Participants receive 2 weeks of therapy with concurrent hypofractionated radiotherapy of 30Gy in 10 fractions to the primary tumour, weekly carboplatin AUC2, weekly paclitaxel 50 mg/m
and durvalumab 1500 mg q4 weekly, followed by durvalumab monotherapy continuing at 1500 mg q4weekly until disease progression, unacceptable toxicity or 24 months of therapy. A single metastasis is treated with stereotactic radiotherapy of 24Gy in 3 fractions in week 7. The trial primary endpoint is the progression free survival rate at 6 months. Secondary endpoints include duration of dysphagia relief, nutritional status change, quality of life, response rate, toxicity, progression free survival and overall survival. The tertiary endpoint is prediction of outcome based on biomarkers identified from patient serial blood samples collected pre- and post-radiotherapy.
This unique investigator-initiated clinical trial is designed to simultaneously address the clinically relevant problems of dysphagia and distant disease control. The overarching aims are to improve patient nutrition, quality of life and survival with low toxicity therapy. AGITG PALEO is a multidisciplinary collaboration and will add to the understanding of the relationship between radiotherapy and the anti-tumour immune response.
Australian and New Zealand Clinical Trials Registry: ACTRN12619001371189 , registered 8 October 2019.