Cetuximab has an inhibitory effect on cell motility in SCC-4 oral squamous cell carcinoma cell line

Cetuximab is a chimeric monoclonal antibody that acts as a competitive antagonist, by binding to EGFR. This cell signalling pathways regulates tumor progression. The oral squamous cell carcinoma undergoes to regional spreading and distant metastasis. This study aimed to evaluate the effect of treatment with Cetuximab on cell migration and invasion in OSCC cells, by using the SCC-4 cell line. Cell migration and cell invasion assay were performed and actin cytoskeleton of control and treated with Cetuximab cells were evaluated. Differences were considered significant when p<0.05.Cetuximab inhibited the migration of SCC-4 cells at three concentrations: 1 µg/mL, 50 µg/mL and 100 µg/mL (p<0.0001) in a dose-dependent manner. The number of SCC-4 treated cells with 1 μg/mL that migrated through the membrane was statistically different from 50 μg/mL (p<0.001) and 100 μg/mL (p<0.0001), and between 50 μg/mL and 100 μg/mL (p<0.01). Cetuximab 50 μg/mL inhibited cell invasion through the MatrigelTM compared with SCC-4 control cells (p<0.01). Cetuximab 50 μg/mL affected the organization of the actin cytoskeleton. Cetuximab has an inhibitory effect on actin cytoskeleton organization, cell migration and invasion, suggesting that Cetuximab treatment can be important to avoid oral squamous cell carcinoma metastasis.

Immunohistochemical study of RhoC GTPase in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a disease with high mortality and morbidity. Metastasis is a significant prognostic factor of the OSCC patients. The Rho GTPases are signaling proteins that controls important cellular processes in various complex mechanisms involved in carcinogenesis. This study aimed to evaluate the expression pattern of RhoC in OSCC protein by immunohistochemistry in situ. Immunohistochemical reactions were performed for RhoC by the method of avitina-biotin-peroxidase activity in samples OSCC: well differentiated (BD, n=6), moderately differentiated (MD, n=24) and poorly differentiated (PD, n=13). The morphometry was taken by QuickScore (percentage and intensity of staining) and only intensity staining. There was no statistical difference (p>0.05) through none of the modes of morphometric analysis between BD, MD and PD. And the RhoC staining was not associated with the histopathologic grading (χ2 = 4.65, p>0.05). However, the morphological evaluation of immunostained for RhoC in cases BD, MD, PD OSCC, regardless of histopathologic grading. These results suggest that there is no correlation between the RhoC immunoexpression and histopathological grading of OSCC.

GTPases Rho distribution in intraepithelial and invasive neoplasias of the uterine cervix

PURPOSE OF INVESTIGATION

To evaluate the distribution of GTPases RhoA, RhoB, and Cdc42 in cervical intraepithelial neoplasias (CIN) and invasive neoplasias of the uterine cervix.

MATERIALS AND METHODS

samples of neoplastic lesions of the uterine cervix of 44 patients were classified in: CIN I (n = 10), CIN II (n = 10), CIN III (n = 09), and invasive carcinoma (n = 15). Antibodies anti-RhoA, anti-RhoB, and anti-Cdc42 were used and staining was classified as: negative, mild, moderate, and intense positive.

RESULTS

When compared with dysplastic cells, superficial cells showed: higher expression of RhoB in CIN I (p = 0.0018), and lower expression of Cdc42 in CIN I (p = 0.0225). The authors observed higher expression of RhoA (p = 0.0002) and RhoB (p = 0.0046) in CIN dysplastic cells when compared with invasive carcinoma cells.

CONCLUSIONS

GTPases Rho may be involved with the regulation of biological processes, important to the progression of cervical neoplasias. Probably, RhoA is important for maintenance of cell differentiation and RhoB protects cells from malignant cervical neoplasia.