Obstacles for T-lymphocytes in the tumour microenvironment: Therapeutic challenges, advances and opportunities beyond immune checkpoint oleh Navin Kumar Verma, Brandon Han Siang Wong, Zhi Sheng Poh, Aiswarya Udayakumar, Ritu Verma, Ryan Kwang Jin Goh, Shane P. Duggan, Vishalkumar G. Shelat, K. George Chandy, Nicholas Francis Grigoropoulos