The combination of RNAscope and immunohistochemistry (IHC) techniques supported the findings from DSP of an overexpression of PD-1 in bacteria-positive microniches in OSCC specimens, in addition to a significant reduction in the levels of Ki-67, suggesting that infected regions of the OSCC and CRC tumour tissue have a lower proliferation potential than uninfected regions (Extended Data Fig. 3a,b). Here, MKI67 is linked to neoplasm.