Tight junction disruption via claudin-6 overexpression promotes invasion and recurrence in high-grade endometrial tumors

Figure 2 Patterns of claudin-6 expression in high-grade endometrial carcinomas and its correlations with histologic subtypes and nodal meastasis. A: Stacked bar graph presenting the distribution of claudin-6 expression status—Group 1 (negative) and Group 2 (positive)—across five histotpathological categories of high-grade endometrial carcinoma. The tumor subtypes are differentiated by color: Orange (1): High-grade endometrioid carcinoma; Blue (2): Serous carcinoma; Green (3): Carcinosarcoma; Purple (4): Clear cell carcinoma; Yellow (5): Poorly differentiated adenocarcinoma. The majority of claudin-6-negative cases are high-grade endometrioid carcinomas, whereas positive expression is more frequently associated with biologically aggressive subtypes such as serous carcinoma, carcinosarcoma, and clear cell carcinoma; B: Stacked bar graph depicting the association between claudin-6 expression and lymph node metastasis. Orange (0): Absence of lymph node involvement; Blue (1): Presence of lymph node metastasis. Compared with the negative cases, the claudin-6-positive tumors (Group 2) presented a notably greater frequency of lymph node metastasis, indicating a potential association between claudin-6 expression and increased metastatic behavior.