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It was established, that HPV virus (Human Papilloma Virus) is responsible for tumor induction in some anatomical regions of head and neck, mainly in palatine tonsils. The characteristics of HPV-related tumors as well as the course of the disease are definitely different compared to tobacco-smoking related tumors; patients HPV-positve have better prognosis - less patients develops recurrences and dies from the disease. There is no full compliance about patients' characteristics, although most indications concern "young adults" with their intensive sexual life. Because the course of HPV-related tumors is milder, there is a need to distinguish the cause of disease to carry on the therapy adjusted to the causative factor. This approach might help to select HPV-negative patients with severe course of disease to apply more aggressive chemotherapy.

Statistics concerning tobacco smoking confronted with cancer epidemiology indicates that only a minority of smokers develops terminal cancer. To much extent it could be explained by genetic polymorphism responsible for a variable risk to develop cancer and its further progression. Then, a comparative analysis of the data concerning cancer deaths regarding a decline of smoking in developed countries unravels other factors previously not considered to represent carcinogenic agents. Human papilloma virus (HPV) could serve as an example of such agent exerting adverse health effects once attributed only to tobacco.

Tobacco smoke-related products and ethanol would induce oxidative modifications to the DNA bases, thereby contributing to larynx cancer. Human 8-oxoguanine DNA N-glycosylase 1 (hOGG1) deals with oxidative DNA damage, and the base changes in the hOGG1 gene may alter the susceptibility of the human cells to tobacco smoke-related compounds and/or ethanol. In the present work, we investigated the association between smoking, drinking or the Ser326Cys polymorphism of the hOGG1 gene and the risk of larynx cancer in a Polish population. It has been reported that the Ser326 allele exhibits higher activity than the Cys326 variant. In this study, 253 age-matched controls and 253 patients with larynx cancer were enrolled. The polymorphism was determined with DNA from blood lymphocytes by polymerase chain reaction. The frequencies (%) of the genotypes were Ser/Ser 65.6, Ser/Cys 30.4, and Cys/Cys 4.0 in the controls and those in patients were 55.7, 36.0 and 8.3, respectively. Stratification of individuals according to their smoking and drinking habits indicated that these habits might be significant risk factors in larynx cancer. The Ser/Cys and Cys/Cys genotypes are significantly associated with the increased risk of larynx cancer. These genotypes increased the risk ratio of larynx cancer among heavy smokers, but did not change the risk in former smokers and moderate smokers. These genotypes also increased the risk of larynx cancer in moderate and heavy drinkers. Therefore, the Cys326 allele of the hOGG1 gene may increase the risk of larynx cancer associated with smoking or alcohol consumption.

Initiation and progression of laryngeal cancer is associated with tobacco smoking and abusing of strong alcoholic beverages. A significance of genetic factor, although not defined sufficiently yet has been raised as well. The studies were focused on an influence of AHR gene polymorphism on survival of squamous cell carcinoma laryngeal subjects. The study material was 65 archival DNA samples analyzed by RLP-PCR. The samples varying with electrophoretic mobility were DNA sequenced. In the study group 9 heterozygotic variants Arg554Lys (codon 554) were detected. One case was a carrier of two other mutations in codon: 490 (1468 A > G) and 570 (1708 G > A). Survival time, metastasis and occurrence of second primary tumors were compared in carriers of wild type and Arg554Lys variant AHR. Preliminary results indicate for a necessity of further studies as until now the study group is too small to find a conclusive association.

Tumour suppressor gene TP53 is a subject of frequent lesions and mutations in a majority of cancer types that is followed by its dysfunction in regulation of cell proliferation, apoptosin and DNA repair. Mutation profile reflects the presence of mutagen-vulnerable sites (including tobacco smoke carcinogens) in its structure. A number of mutations in tobacco smoke-associated cancers are higher than in other types. Particularly, G > T mutation is recognized a signature to benzo(a)pyrene exposure. Further, a mutation profile is dependent on cancer anatomic localization and histological type. There were put forward suggestions concerning estimation of cancer risk and disease prognosis basing of TP53 gene status and expression. The protocols of gene therapy involving TP53 gene are still not satisfactory.

The article presents the current techniques used for the identification of genes involved in tobacco smoke-associated cancers. The focus is set on the techniques derived from the conventional cytogenetics and includes fluorescence in situ hybridization (FISH), comparative genomes hybridization (CGH) and its further improvement that is array-CGH, and other aspects of microarray DNA technology. The second part deals with the main findings concerning participation of oncogenes and tumor suppressor genes in development and progression of tobacco smoke-associated head and neck cancers.

A role of tobacco products in cancer incidence is commonly known and accepted. It is estimated that roughly 1/3 of all the cancers is resulted from previous exposure to tobacco. An impact of tobacco smoke carcinogens in formation of DNA lesions and mutations is well established. Contrary to that, less is known about rearrangements of chromosomes. Nevertheless, there are many indications associating rearrangements of chromosome arms 3p, 3q, 8q, 9p, 17p i 18q with a clastogenic activity of tobacco smoke. An evolution of cytogenetics from conventional techniques to molecular cytogenetics provides an opportunity to find some links between chromosome aberrations and activation of oncogenes as well as deactivation of tumor suppressor genes.

A review presents an incidence of multiple (second) primary tumors of head and neck region resulted from an exposure to tobacco smoke and ethanol. Further, epidemiology, clinical implications, molecular alterations and an impact of genetic factor are described. Finally, alternative theories of origin of multiple primary tumors are discussed.

The incidence of laryngeal cancer is strongly connected with exposure to tobacco smoke containing at least 40 genotoxic carcinogens. DNA lesions induced by tobacco smoke carcinogens can be turned into stable mutations. Oncogenes and tumor suppressor genes are first of all responsible for initiation of carcinogenesis. The same time cells provide such self-protection processes as: carcinogen detoxication, DNA repair and apoptosis. The initiation of carcinogenesis followed by oncogenesis results from the competition between DNA lesions/mutations formation and the protection processes; the latter are genetically controlled.

Recent years a number of cigarette smokers is declining. A part of ex-smokers decided to use e-cigarette nit containing tobacco. We provide a comparison of tobacco smoke and e-cigarette aerosol in respect to chemical composition, toxicity and carcinogenicity. It is stressed that all thy studied parameters were considerably lower in aerosol. The publications dealing with cancer risk following e-cigarettes smoking are not supported by broad epidemiologic data. Altogether, there appeared a hope for reduction of tobacco-smoke associated cancer. [ABSTRACT FROM AUTHOR]