Expression and role of AIM2 inflammasome in early non-small cell lung cancer tissues

ObjectiveTo observe the expression of absent in melanoma 2(AIM2) inflammasome in early non-small cell lung cancer(NSCLC) tissues and its relationship with clinicopathological features, and explore the role and potential mechanisms of AIM2 inflammasome in the pathogenesis of early NSCLC.

MethodsThe paraffin specimens of 57 early NSCLC tissues and their adjacent tissues were collected, including 33 cases of adenocarcinomas and 24 cases of squamous cell carcinoma.Immunohistochemistry assay was used to detect the protein expression of AIM2 inflammasome components AIM2, apoptosis-associated speck-like protein containing a CARD(ASC) and caspase-1, and the downstream cytokines interleukin(IL)-1β and IL-18, their relationship with clinicopathological features was analyzed, and the correlation between the expression of the above proteins was explored.

ResultsThe positive expression rates of inflammasome components AIM2, ASC, caspase-1 and IL-1β, IL-18 in NSCLC tissues were significantly higher than those in adjacent tissues(P < 0.01).The positive expression rates of AIM2, ASC, caspase-1, IL-1β and IL-18 in adenocarcinoma were higher than those in squamous cell carcinoma(P < 0.05 to P < 0.01), which in cancer tissues with low differentiation and lymph node metastasis were higher than those with high-middle differentiation and non-lymph node metastasis(P < 0.05 to P < 0.01), but the difference of which in cancer tissues with different gender, age and tumor size was not statistically significant(P>0.05).In NSCLC tissues, the expression level of AIM2 was positively correlated with the expression level of ASC, caspase-1, IL-1β and IL-18(P < 0.05 to P < 0.01), the expression level of ASC was positively correlated with the expression level of caspase-1, IL-1β and IL-18(P < 0.05 to P < 0.01), and the expression level of caspase-1 was positively correlated with the expression level of IL-1β and IL-18(P < 0.01 and P < 0.05).

ConclusionsThe expression of AIM2 inflammasome components and IL-1β, IL-18 are all up-regulated in early NSCLC tissues, the expression of AIM2 inflammasome in adenocarcinoma is higher than that in squamous cell carcinoma, and its expression level is related to the degree of tumor differentiation and lymph node metastasis.