KHYG-1 cells retain functionality following exposure to the tumour and omental microenvironments of patients with obesity-associated cancer

Natural killer (NK) cell dysfunction has been extensively reported in obesity and cancer. In the setting of obesity-associated cancers such as oesophagogastric adenocarcinomas (OAC), NK cell therapies offer an opportunity to augment anti-tumour immunity and improve outcomes. Herein, this ex vivo study investigated the potential therapeutic utility of KHYG-1 NK cells for OAC and examined how migration towards and exposure to the omental and tumour microenvironments might hinder their future efficacy. OAC patient-derived tissue conditioned media was used to recapitulate the soluble microenvironments of omentum and tumour. Flow cytometric analysis was performed to compare the function and phenotype of KHYG-1 cells to healthy donor blood-derived NK cells and to assess the effects of the omentum and tumour on KHYG-1 function. KHYG-1 cell chemotaxis towards OAC patient-derived adipose-conditioned media (ACM) or tumour-conditioned media (TCM) was assessed by Boyden Chamber assay. KHYG-1 cell cytotoxicity against target cell line K562 was assessed by NK cell cytotoxicity assay. Our functional data reveal that ACM and TCM derived from OAC patients with obesity do not significantly suppress KHYG-1 cell effector function. Furthermore, KHYG-1 cells migrate in significantly higher numbers towards the chemotactic signals of OAC patient-derived omentum, compared to tumour. Interestingly, supplementing the OAC tumour microenvironment (TME) with the chemokine IP-10 enhances KHYG-1 cell chemoattraction. Together, our ex vivo data support the therapeutic potential of KHYG-1 cells in OAC. However, our findings suggest that erroneous KHYG-1 cell migration towards omentum will present a future challenge for their effective migration towards OAC tumour in vivo. To overcome this challenge, this study supports the concept of chemokine profile remodelling as an approach to skew KHYG-1 cell migration towards tumour in OAC. Culture of KHYG-1 with Adipose Conditioned Media (ACM) and Tumour Conditioned Media (TCM) alters the expression of NK cell phenotypic and functional markers while ACM increases their killing capacity. KHYG-1 cell migration towards ACM is significantly higher than their migration towards TCM, however supplementing the TCM with IP-10 increases KHYG-1 cell chemoattraction.