EY1920 Year Book

43 42 Cheng Huen Ki Role of a novel neutrophil subpopulation (APN) in promoting HCC tumorigenesis Background and Aims • High circulating neutrophil-to-lymphocyte ratio is a biomarker of poor clinical outcome in HCC and various cancers. • Recent evidence has shown GM-CSF is highly expressed in the peritumoral area of HCC and can induce expression of APN Hypothesis • APN are present in HCC microenvironment. • APN can induce an immunosuppressive microenvironment and facilitate immune escape of HCC • APN have a protumor role and is a potential immunotherapeutic target Objectives • Confirmpresence of APN in HCCmicroenvironment • Confirm clinical significance of APN in HCC patients • Study the function of APN subpopulation in vivo and in vitro • Develop therapeutic strategy using APN Representative Results Our qPCR data showed that APN markers were elevated in peritumoural areas of HCC patients, and significantly correlated with each other (p<0.001) (Fig.1). Consistent findings were confirmed in immunohistochemistry and flow cytometry(Fig 2). Clinical analysis also demonstrated that APN significantly correlated with tumour size, recurrence, staging, venous infiltration (Fig. 3) and negatively correlated with disease-free survival and overall survival of HCC patients (p<0.05). Life in MRes (Med) Cheng Yum Hung Fredrick, Yeung Wai Ho Oscar, Pang Li, Man Kwan, Lo Chung Mau Department of Surgery, Faculty of Medicine, The University of Hong Kong, Hong Kong, China . Conclusions • Results collectively indicated the novel tumour promoting roles of APN in HCC patients. • Targeting such population may represent a potential therapeutic strategy. Fig.1 IncreasedCD10+HLA-DR+Neutrophils in IntratumoralandperitumoralregionsofHCC Transcriptsanalysis .Geneexpressionof surfacemarkers in intratumoralandperitumoralareas compared tonormal liver tissues. LinearCorrelation .CD66b correlatedwithHLA-DRand CD10 inperitumoralareas. -10 -5 5 10 15 -10 -5 5 10 Peritumour CD66bcorrelationwithHLA-DRandCD10 PeritumorC66b peritumor-HLA peritumor-CD10 R 2 =0.4935, p<0.0001*** R 2 =0.5491, p<0.0001*** n=109 Fig. 3 Correlation between CD66b gene expression level and clinicopathogenic parameters CD66bgeneexpression APNmarker1expression PeritumoralCD66bcorrelationwithAPNmarkers APNmarker2expression Fig. 1 IncreasedexpressionofAPNmarkers inperitu ral and intertumoral regionofHCC Fig. 2SignificanceofAPN in tumorrecurrenceand relapse free survival ofHCC patients MBBS Enrichment Year 2019/20 Cheng Yum Hung Fredrick Full Year < IC - M R e s( Me d) at HK U, H o ng K o ng > Cheng Yum Hung Fredrick