Md Abdullah Al Kamran Khan ^1* Yuhan Sun ¹ Alexander James Sedgwick ¹ Julian Vivian ^2,3,4 Alexandra Jane Corbett ¹ Riccardo Dolcetti ^1,5,6 Theo Mantamadiotis ^1,7 Stefano Mangiola ^8,9 Alexander David Barrow ^1*

• ¹ Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
• ² St Vincents Institute of Medical Research, University of Melbourne, Fitzroy, Victoria, Australia
• ³ Department of Medicine, The University of Melbourne, Melbourne, Australia
• ⁴ Australian Catholic University, Melbourne, Australia
• ⁵ Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
• ⁶ Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Australia
• ⁷ Department of Surgery, Royal Melbourne Hospital, University of Melbourne, Melbourne, Australia
• ⁸ Walter and Eliza Hall Institute of Medical Research, The University of Melbourne, Parkville, Victoria, Australia
• ⁹ Department of Medical Biology, University of Melbourne, Melbourne, Australia

Human natural killer (NK) cells can be sub-divided into two functional subsets but the clinical significance of these CD56 bright and CD56 dim NK cells in anti-tumour immunity remains largely unexplored. We determined the relative abundances of gene signatures for CD56 bright and CD56 dim NK cells along with 3 stromal and 18 other immune cell types in the patient tumour transcriptomes from the cancer genome atlas bladder cancer dataset (TCGA-BLCA).Using this computational approach, CD56 bright NK cells are predicted to be the more abundant tumour-infiltrating NK subset which is also associated with improved patient prognosis. A similar favorable survival trend was projected using gene signatures for mature myeloid dendritic cells (mDC) and CD8 + effector memory T cells (TEM) and unveiled a potential CD56 bright NK-mDC-CD8 + T cell crosstalk in the BLCA tumour microenvironment. Expression of transcripts encoding the activating NK cell receptors, NKG2D, NKp44, CD2, and CD160, showed positive survival trends in combination with CD56 bright NK cell infiltration. Transcription factors including HOBIT, IRF3, and STAT2 were also correlated with CD56 bright NK cell abundance. Additionally, a HOBIT-dependent tissue-residency program correlated with the CD56 bright NK and CD8 + TEM cell signatures was found to be associated with favourable BLCA patient survival. Overall, our study highlights the significance of CD56 bright NK cells in BLCA patient prognosis. Our data facilitates a better understanding of the NK cell anti-tumour responses that may ultimately lead to the development of promising NK and T cell-based therapies for BLCA.