Oral squamous cell carcinoma (OSCC) is the most common malignant tumor of the oral cavity and is usually preceded by a range of premalignant tissue abnormalities termed oral potentially malignant disorders. Identifying malignant transformation is critical for early treatment and consequently improved survival and decreased morbidity. Invadopodia (INV) are specialized subcellular structures required for cancer cell invasion. We developed a new method to visualize INV in keratinocytes using fluorescent immunohistochemistry (FIHC) and semi‐automated images analysis. The presence of INV was used to determine the risk of malignant transformation. We analyzed 145 formalin‐fixed, paraffin‐embedded (FFPE) oral biopsy samples from 95 patients diagnosed as nondysplastic, dysplastic, and OSCC including 49 patients whose lesions transformed to OSCC (progressing) and 46 cases that did not transform to OSCC (control). All samples were stained for Cortactin, tyrosine kinase substrate with five SH3 domains (Tks5) and matrix metallopeptidase 14 (MMP14) using FIHC, imaged using confocal microscopy and analyzed using a multichannel colocalization analysis. The areas of colocalization were used to generate an INV score. Using the INV score, we were able to identify progressing lesions with a sensitivity of 75–100% and specificity of 72–76%. A positive INV score was associated with increased risk of progression to OSCC. Our results suggest that INV markers can be used in conjunction with the current diagnostic standard for early detection of OSCC.

Objective To explore the role of chromokinesin KIF4A in gastric cancer cell invasion using gastric cancer cells SGC-7901 and chromokinesin KIF4A deficient gastric cancer cells (SGC-shKIF4A). Methods Expression levels of KIF4A in controlling gastric cancer cells (SGC-shNC) and SGC-shKIF4A cells were determined by Western Blot. Invasion of gastric cancer cells were assessed using Transwell invasion assay and the number of cells passing through the matrigel was counted. Changing numbers of cortactin in SGC-7901, SGC-shNC, and SGC-shKIF4A cells were analyzed by immunofluorescence staining. Results Compared to the SGC-shNC cells, invasion ability of SGC-shKIF4A cells was increased. Compared to other cells, the numbers of cortactin in SGC-shKIF4A cells was also increased suggesting invadopodia in these cells was increased(P<0.01). Conclusions Chromokinesin KIF4A acts as a tumor suppressor by inhibiting gastric cancer cells invasion and the results provides strong evidences for KIF4A serving as one of potent targets for gastric cancer prognostics and treatment in clinic. Key words: KIF4A; Cortactin; Cell invasion; Gastric cancer cell

AFAP1L1 is strongly associated with malignant osteosarcoma, liposarcoma, and leiomyosarcoma, it localizes to invadopodia and controls cell invasion by a novel Lyn/AFAP1L1/Vav2-Nck2 pathway