Miloš Lazarević, Maja Milošević, Nada Petrović, Slobodan Petrović, Giuseppe Damante, Jelena Milašin and Branislav Milovanović
Background/Aim: Current approaches in therapy of head and neck cancers are surgery, radiotherapy and chemotherapy. However, recurrence, development of multidrug resistance, side effects, and high costs of therapy are significant problems which point to the need for more efficient and less toxic drugs and interventions.
Material and Methods: Eight essential oils obtained from Thymus serpyllum, Mentha piperita, Juniperus communis, Rosmarinus officinalis, Melissa officinalis, Achillea millefolium, Zingiber officinale, and Helichrysum arenarium were tested for their anti-proliferative on oral squamous cell carcinoma (OSCC) culture and SCC-25 cell line. Cytotoxicity assays (MTT and Neutral red) were used to detect the effect of the mentioned essential oils.
Results: T. serpyllum, M. piperita, J. communis, and R. officinalis essential oils exhibited the best anti-proliferative effect, on both types of cells. M. piperita had the greatest effect on SCC-25 cell line (4,5% of viable cells) and OSCC cells (7,2% of viable cells). Overall, cytotoxicity was higher in OSCC than in SCC-25 cell line.
Conclusions: This study showed a clear anti-proliferative effect of four essential oils, in vitro making them novel potential antineoplastic agents.
Nađa Nikolič, Boban Aničić, Zvezdana Tepavčević, Zoran Jezdić, Jelena Čarkić, Boško Toljić, Nasta Dedović-Tanić, Vitomir Konstantinović, Miroslav Vukadinović and Jelena Milašin
Background: Genetic studies of salivary gland neoplasms were mainly focused on chromosomal changes, and some specific patterns of chromosome translocations have been described. However, molecular alterations, in particular the role of HER-2/H-ras/c-myc signalling cascade in pleomor- phic adenoma pathogenesis (PA), are less well characterized. In addition, data on single nucleotide polymorphisms (SNPs) as potential susceptibility factors for PA development are also quite scarce.
Methods: Mutational analyses were performed by means of real-time PCR (HER-2 and c-myc amplification analysis), PCR-SSCP and sequencing (H-ras point mutation detec- tion). Polymorphisms analysis was performed by PCR-RFLP (survivin and MMP-9 genes).
Results: Amplification of HER-2 and c-myc has been found in 13% and 9% of PA cases respectively. Point mutations in H-ras codons 12/13 have been detected in 17% of PAs. No correlation could be established between these alterations and clinical characteristics of PAs, whereas they might play a role in a subset of malignant salivary gland tumours. As for survivin -31 G/C polymorphism, C allele carriers had a 4-fold decrease of the risk of developing PA (p=0.05). Carriers of the variant allele T of the -1562C/T SNP in MMP-9 gene had a 4-fold increase of the risk of developing PA (p<0.001).
Conclusions: A longer follow-up of PA patients harbouring mutations could uncover a prognostic role of HER-2 and c- myc amplification as predictors of adenoma transformation into carcinoma. Both survivin and MMP-9 promoter poly- morphisms represent susceptibility factors for the develop- ment of PAs in the Serbian population.
Nasta Tanić, Jelena Milašin, Tatjana Dramićanin, Maja Bošković, Miroslav Vukadinović, Verica Milošević and Nikola Tanić
Background: Head and neck squamous cell carcinoma, including oral cancer, is the sixth most common cancer worldwide. Despite advances in surgery and treatment, the 5-year survival rate has not improved significantly. There- fore, reliable molecular markers for oral cancer progression are badly needed.
Methods: We conducted a copy number analysis to esti- mate amplification status of c-myc, cycD1 and EGFR onco- genes, mutational PCR-SSCP analysis to determine activa- tion of H-ras oncogene and inactivation of TP55 tumour suppressor gene and methylation specific PCR analysis to evaluate hypermethylation of p16 and MGMT genes.
Results: c-myc oncogene was amplified in 56.7%, cycD1 in 20% and EGFR in 16.7% of Oral Squamous Cell Carci- noma (OSCC) cases while H-ras was activated in 33.3% of samples. Amplification of c-myc was significantly associat- ed with the tumour grade 2. Interestingly, EGFR and H-ras alterations were mutually exclusive. p16 and MGMT were inactivated by hypermethylation in 30% and 13.3% of cases. Co-alteration of cycD1 and p16 were not observed in any of the analyzed samples. TP53 was inactivated in 56.7% of samples and was significantly associated with progression of OSCC, grade 2 and stage 2. Moreover, TP55 and c-myc oncogene were simultaneously altered in grade 2 OSCC.
Conclusions: The most promising marker of OSCC pro- gression remains the TP53 tumour suppressor, which is the most frequently mutated gene in oral cancers. Since there is synergism between TP55 and c-myc, it seems that co- alteration of these two genes could be also a good marker of OSCC progression from gradel to grade 2 tumours.