EGF‐SubA Is Cytotoxic to Laryngeal SCC Cells

Abstract

Objective: 1) Determine the presence, if any, of aneuploidy in premalignant oral leukoplakia (OL). 2) Review the literature with respect to the relevance of aneuploidy as in OL.Method: Tissue was mechanically disaggregated, and cell suspensions were centrifuged (300 rpm/ 5 minutes). After 10 minutes trypsin digestion and treatment with RNAase inhibitors, cell suspension was stained with propidium iodide and spermine. Nuclear DNA content FCM (flow cytometry) measurements were preformed using FACS Calibur FCM with argon laser (488 nm beam).Results: Scrapings from 17 patients for FCM and tissue for morphological evaluations were obtained. Thirteen out of 17 (76%) patients were male. A total of 4 out of 17 were female (24%). All patients were smokers. A total of 4 out of 17 (82%) patients were graded as moderate dysplasia by 2 different oral pathologists, and 3/17 (18%) were graded as having severe dysplasia. The rate of detection of aneuploidy was 0% (0/17). Conclusion:Most published studies focus on DNA aneuploidy in HNC, and evidence for its role in OL is scant. On the basis of our results and the few published trials on this subject, we analyze whether aneuploidy plays a role in the prediction of risk of malignant transformation in OL.Objective: To investigate the effects of GW1929, a new specific PPARgamma agonist, on head and neck squamous carcinoma cell proliferation, apoptosis, and invasion.Method: Human well-differentiated tongue SCC15 cells were treated with 5, 10, 20 micromolar GW1929, and 1% DMSO in 2% FBS Media (control). Tetrazolilum salt WST-1 assay was used to assess proliferation. Cell cycle was analyzed with FACS. Caspase3 was measured with Caspase-Glo3/7 luminescent. RT-PCR measured metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 mRNA to assess anti-invasive effects.Results: GW1929 inhibited tumor cell proliferation. At 24, 48, and 72 hours, treatment with 5, 10, and 20 micromolar GW1929 inhibited SCC15 proliferation by 12% to 23%, 17% to 31%, 27% to 45% in a dose-dependent manner. FACS analysis showed that GW1929 prevented cells from entering S-phase of cell cycle. Confirming significant cellular apoptosis, levels of caspase 3 were 154%, 163%, 185% of control after a 24-hour treatment with 5, 10, 20 micromolar GW1929. GW1929 decreased expression of markers of extracellular matrix invasion in a dose-dependent manner. At 24 hours, levels of MMP-9 mRNA were decreased up to 2 fold, and levels of TIMP-1 mRNA were increased up to 2 fold.Conclusion: GW1929 is a potential antiproliferative agent, as evidenced by its pro-apoptotic, anti-proliferative, and antiinvasive effect on squamous carcinoma of the tongue.Objective: 1) Examine the effect and mechanism of action of EGF-SubA on laryngeal (LSCC) cells. EGF-SubA is a novel cytotoxic drug that promotes cleavage of GRP-78, a key component of the unfolded protein response. 2) Examine the interaction of EGF-SubA with clinically relevant modalities: cisplatin and gamma radiation in LSCC cells.Method: In vitro cytotoxicity was determined for a p...