Stage-dependent and heterogeneous tumor association of Fusobacterium nucleatum in Romanian patients with colon adenocarcinoma

Figure 1 Scatter plot. A: FS17 detection in tumor vs adjacent colonic tissue. Scatter plot of paired quantitative real-time polymerase chain reaction cycle threshold (Ct) values for Fusobacterium nucleatum (F. nucleatum) detected with the FS17 primer set in tumor and adjacent non-tumoral colonic tissues. Lower Ct values indicate higher bacterial detection. Marked interindividual variability was observed, with higher tumor-associated FS17 detection in slightly more than half of the cases; B: Correlation between microRNA-21 (miR-21) expression and FS17 tumor Ct values. Scatter plot illustrating the relationship between miR-21 Ct values and FS17-derived F. nucleatum Ct values in tumor tissue. Pearson correlation analysis demonstrated a weak and non-significant association (r = −0.12, P = 0.66), indicating no direct relationship between miR-21 expression and tumor-associated bacterial detection; C: Correlation between miR-21 expression and FS17 Ct values in adjacent tissue. Scatter plot showing the association between miR-21 Ct values and FS17-derived F. nucleatum Ct values in adjacent non-tumoral colonic tissue. No significant correlation was observed (r = −0.09, P = 0.74), suggesting independent variation of miR-21 expression and bacterial detection in non-tumoral tissue. miR-21: MicroRNA-21.

Figure 2 Cycle threshold values according to preoperative T stage. A: MicroRNA-21 (miR-21) cycle threshold (Ct) values according to preoperative T stage. Distribution of miR-21 Ct values stratified by preoperative tumor T stage. Data are presented as individual values with group distributions. Overlapping ranges across stages indicate no significant differences in miR-21 expression according to local tumor invasion; B: FS17 Ct values in adjacent non-tumoral tissue according to preoperative T stage. FS17-derived Ct values for Fusobacterium nucleatum (F. nucleatum) detection in adjacent non-tumoral colonic tissue stratified by preoperative T stage. No consistent stage-dependent pattern is observed, with overlapping distributions across tumor stages; C: FS17 tumor Ct values according to preoperative T stage. Boxplot showing FS17-derived Ct values for F. nucleatum detection in tumor tissue stratified by preoperative T stage. Lower Ct values in T2 tumors indicate higher bacterial detection compared with T3-T4 tumors, demonstrating a stage-dependent tumor association. miR-21: MicroRNA-21.

Figure 3 Cycle threshold values according to preoperative N stage. A: MicroRNA-21 (miR-21) cycle threshold (Ct) values according to preoperative N stage. miR-21 Ct values stratified by nodal status (N stage). Individual values demonstrate substantial overlap between nodal categories, indicating no significant association between miR-21 expression and lymph node involvement; B: FS17 tumor Ct values according to preoperative nodal status. FS17-derived Ct values for Fusobacterium nucleatum (F. nucleatum) detection in tumor tissue stratified by nodal stage (N0-N2). A progressive increase in Ct values is observed with advancing nodal involvement, although substantial overlap between groups is present; C: FS17 Ct values in adjacent non-tumoral tissue according to nodal status. Boxplot illustrating FS17-derived Ct values for F. nucleatum detection in adjacent non-tumoral tissue stratified by nodal stage. Overlapping distributions indicate no significant association between bacterial detection in adjacent tissue and nodal involvement. miR-21: MicroRNA-21.