Elevated PD-L1 expression on tumor cells, a context associated with an adaptive immune response, has been linked to the total burden of copy number variants (CNVs) in aneuploid tumors, to microsatellite instability (MSI), and to specific genomic driver lesions, including loss of PTEN, MYC amplification, and activating mutations in driver oncogenes such as KRAS and PIK3CA. Triple-negative breast cancers (TNBCs) typically have high levels of CNVs and diverse driver lesions in their genomes. Thus, there is significant interest in exploiting genomic data to develop predictive immunotherapy biomarkers for patients with TNBC. Whole tissue samples from 55 resected TNBCs were screened by immunohistochemistry (IHC) for PD-1 and PD-L1 by using validated antibodies and established scoring methods for staining of tumor and non-tumor cells. In parallel, we interrogated biopsies from each resection with DNA content flow cytometry and sorted the nuclei of diploid, tetraploid, and aneuploid cell populations. CNVs were mapped with CNV oligonucleotide arrays by using purified (>95%) tumor populations. We generated whole exome data for 12 sorted tumor samples to increase the resolution within loci of interest and to incorporate somatic mutations into our genomic signatures. PD-L1 staining was detected on tumor cells in 29 out of 54 (54%) evaluable cases and was associated with increased overall survival (P = 0.0024). High levels of PD-1 and PD-L1 (IHC ≥4) were present in 11 out of 54 (20%) and 20 out of 54 (37%) cases with staining of PD-L1 primarily on tumor cells for 17 out of 20 (85%) cases. The latter included tumors with both high (>50) and low (<20) numbers of CNVs. Notably, homozygous deletion of PTEN (n = 6) or activating mutation in PIK3CA (n = 1) was not associated with increased expression of either immune checkpoint activator in TNBC. In contrast, two treatment-naïve cases with EGFR driver amplicons had high PD-L1 tumor staining. High mutational load and predicted neoepitopes were observed in MSI+ and high CNV burden TNBCs but were not associated with high PD-L1 expression on tumor cells. Our results challenge current models of genomic-based immunotherapy signatures yet suggest that discrete genomic lesions may complement existing biomarkers to advance immune checkpoint therapies for patients with TNBC.
Abstract Antimicrobial resistance is widely recognised as a global threat to human health. This paper explores the mobilisation of biomedical concepts and technologies within local semantic registers and addresses the implications of translation and knowledge complexity for attempts to mitigate the problem of antibiotic resistance. In China, antibiotics are frequently prescribed for common complaints and are widely available without prescription. Drawing on field research in three rural counties of one province, we show that current patterns of antibiotic use are the result of sociocultural, economic and systems drivers within a medical context that draws on precepts from both biomedicine and Chinese medical knowledge. Comparative analysis with European settings suggests that pathogenicity, the set of explanatory frameworks regarding the production of disease, varies socio-temporally in the causal mechanisms that are prioritised. Incorporated within diagnostic strategies that direct treatment towards the bodily response to infection rather than to the infecting pathogen, ‘anti-inflammatory medicine’ as the popular term for antibiotics in parts of Asia foregrounds physiological process over microbial invasion. We examine the articulation of biomedical knowledge paradigms within a non-Pasteurian milieu in relation to socio-historical process, including hybridisation between ontologically distinct medical traditions and the heterogeneity of scientific knowledge claims that underpin contemporary practices of antibiotic prescribing. We conclude that the concept of inflammation functions as a boundary object which effectively mediates the interfaces between popular knowledges, biomedical sciences and local medical practices. Our analysis may have wide relevance because popular and scientific understandings of inflammation alike draw on metaphors grounded in universal sensory experience that provides a common basis for culturally diverse conceptual elaboration. Situated understandings of inflammation and associated treatment preferences constitute a contextually coherent response to available medical technologies in community health care. Our analysis also calls into question simplistic interpretations of antibiotic use for non-bacterial conditions as deriving from lack of education or public awareness and suggests a need to reconsider current public health knowledge translation strategies.
BackgroundActivation of the JAK/STAT pathway is common in triple-negative breast cancer (TNBC) and affects the expression of genes controlling immune signaling. A subset of TNBC cases will have somatic amplification of chromosome 9p24.1, encoding PD-L1, PD-L2, and JAK2, which has been associated with decreased survival.Materials and MethodsEleven TNBC cell lines were evaluated using array comparative genomic hybridization. A copy number gain was defined as an array comparative genomic hybridization log2 ratio of ≥ 1. Cell surface expression of programmed cell death ligand 1 (PD-L1) was detected using flow cytometry and compared with the median fluorescence intensity of isotype control immunoglobulin. To selectively inhibit JAK2, lentiviral vectors encoding 2 different short hairpin RNA (shRNA) were generated. JAK2, STAT1, STAT3, phosphorylated (p) STAT1, and pSTAT3 expression were measured by immunoblot. Statistical significance was defined as P < .05.ResultsThe cell line HCC70 had 9p24.1 copy number amplification that was associated with both increased JAK2 and pSTAT3; however, knockdown of JAK2 inhibited cell growth independently of 9p24.1 copy number status. In TNBC cell lines with 9p24.1 gain or amplification, PD-L1 expression rapidly and strikingly increased 5- to 38-fold with interferon-γ (P < .05), and inducible PD-L1 expression was completely blocked by JAK2 knockdown and the JAK1/2 inhibitor ruxolitinib. In tumor tissue, expression of interferon-γ–related genes correlated with 9p24.1 copy number status.ConclusionThese data suggest that the JAK2/STAT1 pathway in TNBC might regulate the dynamic expression of PD-L1 that is induced in the setting of an inflammatory response. Inhibition of JAK2 might provide a synergistic therapy when combined with other immunotherapies in the subset of TNBC with 9p24.1 amplification.
Introduction This study aims to investigate patterns of antibiotic treatment-seeking, describe current levels of and drivers for antibiotic use for common infections (respiratory tract and urinary tract infections) and test the feasibility of determining the prevalence and epidemiology of antimicrobial resistance (AMR) in rural areas of Anhui province, in order to identify potential interventions to promote antibiotic stewardship and reduce the burden of AMR in China. Methods and analysis We will conduct direct observations, structured and semistructured interviews in retail pharmacies, village clinics and township health centres to investigate treatment-seeking and antibiotic use. Clinical isolates from 1550 sputum, throat swab and urine samples taken from consenting patients at village and township health centres will be analysed to identify bacterial pathogens and ascertain antibiotic susceptibilities. Healthcare records will be surveyed for a subsample of those recruited to the study to assess their completeness and accuracy. Ethics and dissemination The full research protocol has been reviewed and approved by the Biomedical Ethics Committee of Anhui Medical University (reference number: 20170271). Participation of patients and doctors is voluntary and written informed consent is sought from all participants. Findings from the study will be disseminated through academic routes including peer-reviewed publications and conference presentations, via tailored research summaries for health professionals, health service managers and policymakers and through an end of project impact workshop with local and regional stakeholders to identify key messages and priorities for action.
Abstract Background: Checkpoint blockade (CKB) are in clinical trials in breast cancer, but responses may be limited by the low tumor micro-immune profile and somatic mutation burden. Oncolytic viruses may function by activating the immune microenvironment, and improve clinical responses when combined with CKB against cancers like melanoma. In this study, we evaluate the synergy of cytotoxic T lymphocytes (CTLs) combined with oncolytic myxoma virus in an in vitro model of human breast cancer. Method: BMLF1-CTLs were generated from human HLA-A*02 PBMCs, which were stimulated with antigen presenting cells pulsed with the EBV BMLF1 HLA-A*02 peptide (GLCTLVAML). MCF-7 was engineered to express the full-length BMLF1 gene from EBV. To assess the impact of myxoma virus infection on CTL cytotoxicity, target MCF-7 cells (+/- BMLF1) were co-cultured with BMLF1-CTLs (E:T ratio=5:1) and myxoma virus vMyx-M135KO-GFP (vMyx135KO), at multiplicity of infection (MOI) ranges from 0.1 to 10 ffu/cell, in vitro for 48 hours. Cytotoxicity was measured by flow cytometry with propidium iodide (PI). Cell surface expression of MHC class I and class II were measured by flow cytometry. Statistical comparisons were performed using an unpaired t-test and variation among and between groups was calculated using ANOVA. Statistical significance was defined as p<0.05. Results: At the highest MOI (10 ffu/cell), cell surface MHC class I expression on MDA-MB-231 was decreased 38-fold (p<0.01), compared to untreated control. MCF-7 was more sensitive to MHC class I downregulation (MOI 1 ffu/cell, 37.3-fold reduction, p<0.002). No significant change of cell surface expression of MHC class II was detected in either breast cancer cell lines at any MOI. In MCF-7-BMLF1- cells, baseline cytotoxicity remained low in both CTL and vMyx135KO (MOI=0.1 ffu/cell) only treatments (14% vs. 10%). With antigen expression (MCF-7-BMLF1+), CTL cytotoxicity increase to 21% (p=0.02). At a MOI of 0.1 ffu/cell, vMyx135KO viral infection further sensitized cells to CTL cytotoxicity (21% vs. 36%, p<0.001) Conclusions: Oncolytic myxoma virus infection can decrease the MHC class I expression in human breast cancer cell lines, but only at high multiplicities of infection. At low level of virus, myxoma virus infection can enhance CTL cytotoxcity of breast cancer cell line. Citation Format: Meixuan Chen, Ana L. Matos, Padhmavathy Yuvaraj, Laura Belmont, Grant McFadden, Karen S. Anderson. Synergy of CTL tumor cytotoxicity with myxoma oncolytic virotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4093.
Background: Checkpoint blockade (CKB) are in clinical trials in breast cancer, but responses may be limited by the low tumor micro-immune profile and somatic mutation burden. Oncolytic viruses may function by activating the immune microenvironment, and improve clinical responses when combined with CKB against cancers like melanoma. In this study, we evaluate the synergy of cytotoxic T lymphocytes (CTLs) combined with oncolytic myxoma virus in an in vitro model of human breast cancer.Method: BMLF1-CTLs were generated from human HLA-A*02 PBMCs, which were stimulated with antigen presenting cells pulsed with the EBV BMLF1 HLA-A*02 peptide (GLCTLVAML). MCF-7 was engineered to express the full-length BMLF1 gene from EBV. To assess the impact of myxoma virus infection on CTL cytotoxicity, target MCF-7 cells (+/- BMLF1) were co-cultured with BMLF1-CTLs (E:T ratio=5:1) and myxoma virus vMyx-M135KO-GFP (vMyx135KO), at multiplicity of infection (MOI) ranges from 0.1 to 10 ffu/cell, in vitro for 48 hours. Cytotoxicity was measured by flow cytometry with propidium iodide (PI). Cell surface expression of MHC class I and class II were measured by flow cytometry. Statistical comparisons were performed using an unpaired t-test and variation among and between groups was calculated using ANOVA. Statistical significance was defined as p<0.05.Results: At the highest MOI (10 ffu/cell), cell surface MHC class I expression on MDA-MB-231 was decreased 38-fold (p<0.01), compared to untreated control. MCF-7 was more sensitive to MHC class I downregulation (MOI 1 ffu/cell, 37.3-fold reduction, p<0.002). No significant change of cell surface expression of MHC class II was detected in either breast cancer cell lines at any MOI. In MCF-7-BMLF1- cells, baseline cytotoxicity remained low in both CTL and vMyx135KO (MOI=0.1 ffu/cell) only treatments (14% vs. 10%). With antigen expression (MCF-7-BMLF1+), CTL cytotoxicity increase to 21% (p=0.02). At a MOI of 0.1 ffu/cell, vMyx135KO viral infection further sensitized cells to CTL cytotoxicity (21% vs. 36%, p<0.001)Conclusions: Oncolytic myxoma virus infection can decrease the MHC class I expression in human breast cancer cell lines, but only at high multiplicities of infection. At low level of virus, myxoma virus infection can enhance CTL cytotoxcity of breast cancer cell line.Citation Format: Meixuan Chen, Ana L. Matos, Padhmavathy Yuvaraj, Laura Belmont, Grant McFadden, Karen S. Anderson. Synergy of CTL tumor cytotoxicity with myxoma oncolytic virotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4093.
Primary care clinicians in rural China are required to balance their immediate duty of care to their patients with patient expectations for antibiotics, financial pressures, and their wider responsibilities to public health. They appear to make greater efforts in managing immediate clinical risks and personal reputation, than in considering the long-term consequences of their actions as potentially contributing to antimicrobial resistance. This paper employs Bourdieu's theory of capital to examine the perspectives and practices of Chinese primary care clinicians prescribing antibiotics at low-level health facilities in rural Anhui province, China. We examine the institutional context and clinical realities of these rural health facilities and identify how these influence the way clinicians utilise antibiotics in the management of common upper respiratory tract infections. Confronted with various official regulations and institutional pressures to generate revenues, informants' desire to maintain good relations with patients and their concerns for patient safety result in tensions between their professional knowledge of 'rational' antibiotic use and their actual prescribing practices. Informants often deferred responsibility for antimicrobial stewardship to the government or upper levels of the healthcare system and drew on the powerful public discourse of "suzhi" (human quality) to legitimize their liberal prescribing of antibiotics in an imagined socioeconomic hierarchy. The demands of both practitioners' and patients' social, cultural, and economic forms of capital help to explain patterns of antibiotic prescribing in rural Chinese health facilities.