Main findings and Interpretation
Patients with the 2009 FIGO stage of IB1-IIA2 CC will undergo pLN
resection and impair the patient’s quality of life [8,40].Begin with this study, our TCGA data originated from bioinformatics
analysis demonstrated that LN metastasis of CESC may be related to
immune infiltration. Results stressed that the major immune infiltration
cell types were natural killer (NK) cells, macrophages and T cells.
In addition, traditional procedures have been used to elucidate the
mechanism by regularly exploring such molecular pathways which would
destroy the spatial structure[41,42]. By mIF and HALO system, their
spatial orientation interrelation of immune cells and immune markers
would be preserved [19,43]. Our results further revealed that immune
infiltration, including CD68, PD-1 and PD-L1 were significantly
up-regulated and CD8 was significantly down-regulated with pLN
metastasis of CC. This can be explained as macrophages and the immune
molecule PD-1, PD-L1 may promote pLN metastasis of CC.
Thirdly, by Pearson correlation coefficients (R) and linear regression,
we further found a significant positive correlation between CD3 and CD8,
CD3 and CD56, CD3 and CD68, CD8 and CD56, CD8 and PD-1, CD8 and PD-L1,
CD56 and CD68, CD56 and PD-1, cd56 and PD-L1, PD-1 and PD-L1 in CC
without pLN metastasis. With pLN metastasis, these correlations were
enhanced between CD3 and CD8, CD8 and CD56, CD8 and CD68. While these
correlations became weaken between CD3 and CD68, CD8 and PD-1, CD8 and
PD-L1, CD56 and PD-1, CD56 and PD-L1, PD-1 and PD-L1. These results
indicated that a large number of T cells are activated, and enhanced
communication with macrophages and NK cells may be involved in pLN
metastasis of CC.
Fourthly, by spatial proximity analysis, the average distance (um)
between CD8 and CD56, CD8 and CD68, CD8 and PD-1, CD8 and PD-L1, CD56
and PD-1, CD56 and PD-L1 were significantly closer with pLN metastasis.
These data have demonstrated that CD8+ T cells, NK cells and macrophage
may be involved in pLN metastasis of CC. To sum up to above two points,
these data further proved that the interaction between T cells and NK
cells, as well as T cells and macrophages may promote the metastasis of
pLN metastasis in CC.
Lastly, based on randomly selected sixty percent patients, a diagnostic
prediction model was established and the AUC can reach 0.843. The
nomogram incorporates five items of PD-1, PD-L1, the average distance of
CD56 to PD-1, the average distance of CD56 to PD-L1, and the average
distance of PD-1 to PD-L1. By internally validation with the remaining
40 percent of cases, a new ROC curve was emerged and the AUC reaching
0.888.
Summary with this information, T cells interact with NK cells and
macrophages through PD-1 and PD-L1 to promote pLN metastasis of CC.
Our nomogram can serve as an effective preoperative predictive tool to
assess pLN status in CC patients.
Cervical biopsy is an essential step before the diagnosis of CC. In the
process, we can take part of cancer tissue through cervical biopsy for
mIF detection. HALO system is further applied in quantitative and
spatial analysis. By the diagnostic prediction model, we can predict pLN
metastasis preoperatively, thus avoiding unnecessary routine pLN
dissection. In this way, we can avoid additional surgical trauma and
possible complications for
patients.