Biorilms are structured communities of bacterial cells enclosed in a self-produced polymeric matrix that are adherent to an inert or living surface. Their growth on the surface of catheter lines, artificial joints and other surgical implants is of major medical concern. As many laboratory strains have become accustomed to standardised conditions, they are not necessarily representative of clinical strains. This study investigated the effect of horse blood, human blood and human blood components on biofilm. formation by clinical and laboratory isolates of Escherichia coli and Campylobacter jejuni using a 96-well microtitre plate method, crystal violet staining and confocal laser scanning microscopy. The results for the E. coli laboratory isolatesi ndicated a decreasein biofilm fonnation in Luria-Bertani (LB) broth supplemented with lysed horse blood, whole and lysed human blood, human plasma, human serum and whole and lysed human red blood cells. Conversely, the results for the E. coli clinical isolates showed an increase in biofilm formation in LB broth supplemented with either lysed horse blood or lysed human blood. Supplementation with human serum decreased biofilm formation by these clinical strains, whilst the addition of human plasma appeared to be inhibitory to biofilm formation. Of the clinical E. coli, only the urine derived strains showed a significant increase in biofilm formation in LB broth with added whole human red blood cells or whole human blood and produced haemolysin. The results for the C. jejuni isolates used in this study indicated a large increase in biofilm formation when grown in Bolton Broth (BB) supplemented with lysed horse blood, lysed human blood or lysed human red blood cells. This increased biofilm formation was not observed for cultures grown in BB supplemented with human serum, human plasma, whole human blood, iron or whole human red blood cells.

Momordica charantia fruit is traditionally used as a vegetable in the Indian subcontinent and is claimed to have hypoglycaemic effects in human and experimental diabetes. The oral administration of M. charantia fruit juice was investigated for its effects in streptozotocin (STZ)-induced diabetes in rats. The results of this study have revealed that the fruit juice administration reduced the blood glucose levels, improved glucose tolerance and increased blood insulin levels and body weights in STZ-induced diabetes in rats. However, the treatment of fruit juice did not completely normalize these parameters as the values were still significantly different from those of age-matched controls. The systolic blood pressure was significantly increased in diabetic animals when compared to untreated diabetic rats. The treatment of Lvi. charantia to diabetic animals completely prevented such an increase as the values were not significantly different from that of age-matched controls. The administration of M charantia to STZ-induced diabetic rats also reduced the absorption of glucose by the brush border of small intestine. A similar reduction in glucose uptake by muscle cells in vitro was also observed. In an immunohistochemical study of the pancreas on number and distribution of endocrine cells, a significant increase in the number of insulin positive cells was observed in Lvi charantia treated-diabetic animals as compared with untreated diabetic rats. However, their number was still significantly less than that obtained for control animals. The effect of M charantia treatment on myelinated fibre abnormalities in the tibial nerve of STZ- induced diabetic and control rats was also investigated. The mean cross-sectional myelinated fibres area (p C 0.03), axonal area (p C 0.02) and myelin area (p < 0.04) including the mean maximum myelinated fibres area (p C 0.03) were significantly reduced in untreated diabetic animals when compared with age-matched controls. In the M. charatia treated diabetic animals, myelinated fibre area and myelin area were significantly greater than untreated diabetics (p C 0.05) and not significantly different from age-matched controls. The mean value for the maximum fibre area was also significantly greater than that of untreated diabetics (p< 0.05) and was not significantly different from that of age-matched controls. In summary, the administration of M. charantia normalised the structural abnormalities of peripheral nerves in experimental diabetes. The changes in STZ-induced diabetes related to oxidative stress and expression of P450 and GST isoenzymes was studied. The results indicated an increase in CYP4Adependent laurie acid hydroxylation in liver, kidney and the brain of STZ-diabetic rats. An increase in CYP2B-dependent aniline hydroxylation and CYP lA-dependent ethoxycoumarin-O-deethylase activities was also observed. A significant increase in aminopyrene-N-demethylase activity was observed only in rat kidney while there was a decrease in the liver and brain of diabetic rats. A significant increase in NADPHdependent lipid peroxidation (LPO) in kidney of diabetic rats was also observed. On the other hand, a decrease in hepatic LPO was seen during chronic diabetes. During diabetes an increased expression of CYP1AI, CYP2E1 and CYP4A2 proteins was also seen by western blot analysis. Mi charantia fruit juice feeding modulated the protein expression and catalytic activities in a tissue and isoenzyme specific manners. A marked decrease in hepatic glutathione (GSH)) content and glutathione Stransferase (GST) activity and an increase in brain OSH and GST activity was observed in diabetic rats. On the other hand, renal GST was markedly reduced while GSH content was moderately higher than that of control rats. Western blot and immunohistochemical analysis using specific antibodies have confirmed the tissue specific alterations in the expression of OST isoenzymes. M. charantia juice feeding, in general, reversed the effect of long tenn STZ-diabetes on the modulation of both P450-dependent monooxygenase activities and GSH-dependent oxidative stress related LPO and GST activities. These effects were found to be tissue specific and related to the modulation of various specific isoenzymes during diabetes. These results have suggested that the modulation of xenobiotic metabolism and oxidative stress in various tissues may be related to altered metabolism of endogenous substrates and hormonal status during diabetes. These findings reported in this thesis may have implications in elucidating the therapeutic use of M charantia in the management of diabetes mellitus.

The action of AcrAB-ToIC, a multidrug efflux system of Escherichia co/i, is largely responsible for the increased intrinsic resistance of this organism to many antimicrobial agents. The level of mRNA specific to the acrAB efflux genes is elevated by six-fold during exponential phase of growth in LB broth. In MOPS minimal medium supplemented with 0.4 % (w/v) glucose, levels of acrA mRNA remain higher for a prolonged period of time concurrent with the delayed onset of stationary phase, suggesting that transcription of this gene is linked with active growth. A case for transcriptional activation of this gene by RNA polymerase associated with the "housekeeping" sigma factor, a 7o, is presented. Investigation of acrAB transcription in E. co/i SD1648 using the acrAB::lacZ reporter system encoded on a plasmid (pNN602) appears to contradict these fmdings, suggesting that acrAB transcription is induced upon entry into stationary phase. This paradox is attributed to fundamental differences between the two methods of investigating transcription, and suggests that acrAB expression is subject to post-transcriptional regulation or that the plasmid based reporter system fails to convey an important aspect of control. Notably acrA niRNA levels suggest transient induction of acrA transcription upon transition into stationary phase of growth; however this is secondary to the observed exponential phase peak in transcript levels. In addition to the general stress conditions already found to induce acrAB transcription including 0.4 % (v/v) ethanol and 0.5 M sodium chloride, bile salts (cholate and deoxycholate), ampicillin, and growth on certain carbon sources, were found to induce acrAB transcription. A family of isogenic mutant strains based on the lacZ derivative of E. co/i MG1655 (SD 1648) harbouring specific gene disruptions was constructed in order to investigate the effect of key regulatory factors on transcription of the acrAB genes. CRP-cAMP, FIS, H-NS, Rob, AcrR, OmpRJEnvZ, CsrAB, and SdiA were all found to have significant effects on acrAB transcription. A real-time reverse transcription-polymerase chain reaction (RT-PCR) assay, using the Roche LightCyclerTM Instrument, was developed for the purpose of this investigation of acrA gene transcription. The assay was used specifically to quantify acrA mRNA levels; however the method can readily be applied to the study of other E. coli genes. The method was uniquely applied to the investigation of acrAB transcription throughout the growth cycle of E. co/i during batch culture in LB broth, in order to ascertain the patterns of expression for this gene. Following this, the RT-PCR assay was used as a novel approach to determining the start of transcription for the acrAB genes. Where transcription is initiated from more than one promoter, this method could be applied further to determine the relative strengths of each promoter, in vivo, under different conditions. In the case of the acrAB genes a promoter was located between 224 and 383 bases upstream from the acrA start of translation. This suggests that at least two promoters exist upstream of the acrAB genes, the implications of which are discussed.

The United Arab Emirates (UAE), like many other developing countries, has witnessed a rapid development in many aspects of life during the last three decades. The discovery of oil in the middle of the last century has contributed to significant social change and UAE, along with other Gull Arab States, have experienced a rapid transition in its socio-economic status. Rapid economic growth in IJAE has brought about marked changes both in lifestyles and in patterns of health and disease. With the greater availability of housemaids, cars, televisions and other sophisticated household appliances, the lifestyles of UAE nationals have become more sedentary, and watching television and eating snacks are some of the main4eisure-time activities. The consumption of traditional food items have also decreased with urbanization and life-style changes in the UAE community, and hypertension have become a major public health problem. To date, there are no systematic studies of the relationship between hypertension and socioeconomic factors such as income and demographic factors including education and occupation in the UAE population have been undertaken. Since each community has its own common and unique socioeconomic determinants for cardiovascular diseases, particularly hypertension, it is important to study these variables in individual communities. In the UAE, it is believed that the effect of income, education and occupation are much weaker than in the developed countries due to the differences in the educational levels and the differences in the economy of the country. This study investigated the association between the incidence of hypertension and socioeconomic factors including income. The study included 500 hypertensive adults aged 20-65 years from the Primary Health Care (PHC) Clinics along with a randomly selected sample of 500 normotensive control subjects. Face-to-face interviews were done and data were gathered on socio-economic status (SES). age, gender, nationality, educational level, occupation, place of living (urban and semiurban), parity, income level, cigarette smoking habit, physical activity, lifestyle habits, body mass index, social support, chronic life difficulties, perceived stress and iritability. Hypertension was defined according to World Health Organization (WHO) criteria as Systolic Blood Pressure (51W) > 140 mm Hg and/or Diastolic Blood Pressure (DBP) > 90 mm Hg and/or on antihypertensive treatnent. The data were analyzed using the Statistical Packages for Social Sciences (SPSS). Student's t-test, Mann-Whitney test, chi-square test and ANOVA test were used to assess the relationship between these factors and the incidence hypertension. SBP and DBP. For the Arab expatriates, the present study found a statistically significant association between socioeconomic factors (particularly income and education) and the incidence of hypertension and elevated blood pressure. In contrast, the study has also found no significant relationship between the incidence of hypertension and socioeconomic factors among UAE nationals. The results of this study showed a significant relationship between most of the studied psychosocial risk factors and hypertension. There was a significant relationship between hypertension and social support, perceived stress and chronic life difficulties. The results provided clear evidence that the effect of psychosocial risk factors in the development of hypertension is more pronounced among Arab expatriates compared to UAE nationals. Not surprisingly, the study has also found a significant relationship between the incidence of hypertension and some of the known hypertension-related risk factors. A significant association was found between the incidence of hypertension and body mass index, cholesterol abnornmlity. smoking, saturated fat consumption, excessive salt constiiiiption. physical exercise, cardiovascular disease, diabetes, renal problems and family history of hypertension. In addition, psychosocial stressors and other personal health habits such as diet (saturated fat consumption), physical activity, smoking and body weight are significantly related to blood lipid profiles. There was also a significant association between many of the above-mentioned risk factors and the socioeconomic factors, particularly, income and education. However, the pattern and the strength of these associations were not similar for UAE nationals and expatriates. The study observed relatively lower levels of the above-mentioned risk factors among UAE nationals with low socioeconomic status as compared to the expatriate group. Differences between the two groups with regard to the relationship between socioeconomic factors and the incidence hypertension is interesting and deserves further exploration. In conclusion, it would seem that the differences in SES and the prevalence ofhypertension morbidity are mediated at least in part, by some hypertension-related risk factors observed in this study. Despite the limitations and difficulties in measuring SES (particularly income), the evidence observed in this study that SES is a major determinant of hypertension especially among expatriates living in the UAE is of significant clinical importance.

Xerostomia (dryness of the mouth) is a prevalent condition amongst elderly and diabetic populations which leads to marked alterations in oral health. The parotid glands play major roles in maintaining salivary secretions to assist in the lubrication and protection of the oral cavity and in digestion. This study investigated the effects of ageing and streptozotocin (STZ)-induced diabetes on the structure and function of the rat parotid gland. Rats (2-6, 12, 16-18 and 22-24 months old) were obtained from a recommended Home Office supplier and diabetic rat models were achieved by employing STZ. The results showed that aged glands were disorganised and infiltrated with connective tissues, lipid droplets and mast cells compared to younger control glands. A significant (P < 0.05) reduction in the mean acinar cell number was also observed in aged glands. Parotid glands taken from STZ-induced diabetic rats showed extensive infiltration of lipid droplets when compared to glands of agematched control rats. Acetylcholine (ACh), noradrenaline (NA) or isoprenaline (ISOP) elicited marked increases in amylase release from parotid acini of 2-6 month old (control) rats. However, this amylase release was significantly (Pc0.05) reduced in parotid acini of 12, 16-18 and 22-24 month old rats. In parotid segments of STZinduced diabetic rats, both ACh and NA (1xl0 5 M for both) evoked a significant (P < 0.05) reduction in amylase secretion when compared to responses obtained from age-matched control rats. Similarly, in parotid acini from STZ-induced diabetic rats, both ACh and NA induced the dose-dependent release of aniylase, but this response was significantly (Pc0.05) reduced compared to the results from age-matched control rats. In Fura-2-loaded parotid acinar cells, significant (Pc0.001) reductions in the peak and plateau phases of ACh-evoked Ca 2 signals (17340/17380) from parotid acinar cells isolated from animals aged 16-18 months were observed, compared to parotid acinar cells of 2-6 month old rats. In parotid acinar cells of STZ-induced diabetic rats a significant (PcO.00l) reduction in only the plateau phases of the Ca 2 signals was observed, in 2.5 mM [Ca2 ]0. However, in 0 mM [Ca2 ]3 the plateau phase remained inhibited, but basal Ca2 signals were also reduced in parotid acinar cells of STZinduced diabetic rats, but not in parotid acinar cells of age-matched control rats. An elevation in the total Ca 2 concentration in whole gland segments from STZ-induced diabetic rats was also observed compared to age-matched control rats. Treatment of glands from 2-6 and 12 month old rats with .t-butyl hydroperoxide (tH202) resulted in marked time-dependent (2 and 4 Lu) increases in cytochrome c fluorescence, compared to untreated glands. In contrast, treatment of glands from 22-24 month old rats for the same time periods showed no apparent increases in cytochrome c compared to the other two age groups. Incubation of acini with either 0.5, 1 or 2 mM H202 resulted in significant (Pc0.05) increases in amylase release compared to basal levels in the absence of H202. In addition, stimulation of acini suspensions with either ACh, NA or ISOP (1x10 7 M-lxlO4 M for all) resulted in the dose-dependent release of amylase above basal level. However, pretreatment of acini with 1 mM H202 followed by the addition of either ACh, NA or ISOP resulted in significant (Pc0.05) decreases in amylase release compared to responses with secretagogues alone. Analysis of acyl lipids showed that the TAGIPL ratio was significantly (PC0.01) higher in glands from aged animals compared to younger animals. Glands from STZinduced diabetic animals showed significant (P < 0.05) alterations in total acyl lipid profiles, 16:1/16:0 and 18:1/18:0 fatty acid ratios, relative proportions ofPL and TAG aèyl lipids and [ 14C] labelled TAG/PL ratios. The results of this study showed that both ageing and STZ-induced diabetes was associated with marked morphological and physiological changes in the rat parotid gland.

Nucleic acid amplification methods (PCR) were investigated for the detection of Campylobacter species in foods and environmental waters. A novel species-specific PCR was adapted into a high-throughput, colorimetric end-stage detection format (PCR ELISA). The sensitivity of detection of the PCR ELISA assay was equivalent to one genome copy and was demonstrated to be 100-fold more sensitive than a conventional gel electrophoresis-based PCR method. The novel species-specific PCR assay was adapted into a quantitative real-time format (TaqMan) for accurate quantification of the numbers of C. jejuni cells present in food samples. Quantification was demonstrated over six orders of magnitude between 1.2 x 101 to 1.2 x 107 genome equivalents per reaction, with a limit of detection of 10 genome equivalents. The PCR ELISA and real-time PCR assays were validated for the specific and sensitive detection of C. jejuni and C. coil in naturally contaminated food and environmental water samples. Methods for the extraction of DNA from foods and enrichment cultures were investigated and an optimised method (PrepMan) determined. The PCR ELISA and real-time PCR assays significantly reduced the time taken for the detection of C. jejuni and C. co/i in foods and waters to seven hours and two and a half hours respectively. Previous studies have indicated that detection of mENA by reverse transcriptase PCR (RT-PCR) may reflect viability in the detected organism. RT-PCR assays were m developed for the detection of thee C. jejuni mRNA targets, DNase treatment of extracted RNA was optimised and appropriate controls for RT-PCR in bacteria established. The assays were applied to the detection of heat-killed and chlorine-killed cell suspensions with diflèrentiation between viable and heat-killed cells being demonstrated. However, problems with target-dependent variations in the halilives of the mRNA targets were identified which have major implications for the use of RT-PCR to establish the viability of contaminating pathogens in processed food samples. The PCR ELISA and real-time PCR assays are high-throughput methods for the sensitive and specific detection of C. jejuni and C. coli in foods, and are an important model for other foodborne pathogens.

Broodiness in the domestic hen is characterized by incubation of eggs and subsequent care of the young. Incubation behaviour is initiated by increased plasma progesterone and oestrogen from maturing ovarian follicles that induce nesting behaviour. This is subsequently transformed into incubation behaviour by increased plasma prolactin in association with decreased gonadotrophin and ovarian steroid secretion. Gonadotrophin secretion is under the stimulatory and inhibitory control, respectively, of gonadotrophin releasing hormone-I (GnRFI-I) and gonadotrophin inhibitory hormone (GnIH). Prolactin secretion is controlled by the stimulatory action of the hypothalamic neuropeptide, vasoactive intestinal polypeptide (VIP). The aim of this study was to increase understanding and knowledge of the interactions between these hormones and neuropeptide in the neuroendocrine control of incubation behaviour in the domestic hen. Observations were made using fluorescence immunocytochemistry with additional data on progesterone receptor mRNAs, using PCR to localize the receptor. Hypothalamic progesterone receptor immunoreactivity (PR-ir) was seen in several hypothalamic nuclei and areas including the organum vasculoswn terminalis (OVLT) and basal hypothalamic tuberal region (TU). The density of cells containing PR-ir in the OVLT and TU, but not at other hypothalamic loci, was lower in incubating than in laying hens. In the anterior pituitary gland, PR-ir was localised in luteinizing hormone (LH) but not prolactin cells, and the density of cells containing LH and PR-ir was lower in incubating than in laying hens. The density of prolactin cells was higher in incubating than in laying hens. Progesterone receptor B mRNA was found in It the TU and pituitary gland in both laying and incubating hens. Prolactin receptor, but not progesterone receptor, was co-localised in VIP neurones in the TU. The number of visible VIP-ir cell bodies containing prolactin receptor was greater in incubating than in laying hens. Nerve fibres containing VIP did not contact GnRH-I-ir cell bodies, but potential contact between those VIP and GnRJ-I-I fibres was seen in the median eminence. GnIH was localized in cells in the paraventricular nucleus (PVN) in incubating and laying hens did not contain PR-ir and had terminals in the median eminence. The density of GnIH neurones did not differ between laying and incubating hens, but their size of the cell bodies was significantly larger in incubating hens. Although GnRFI-Iir and GnIH-ir fibres were abundant in the PVN, they were not observed to come into close contact. It is concluded that incubation behaviour and associated changes in either prolactin or gonadotrophin secretion could be mediated through progesterone receptor B in the OVLT and TU. Progesterone is likely to exert feed-back control of LH secretion at the level of the pituitary gland in laying, but not in incubating hens through progesterone receptor B. Prolactin may act directly on basal hypothalamic VIP neurones to regulate it own secretion. Increased GnIH release in incubating hens may contribute to depressed gonadotrophin secretion.

The ring dove (Streptopelia risoria) is a usefUl animal model for the identification of neural and hormonal determinants of reproductive behaviours. Studies were undertaken to investigate the role of dopamine and progesterone in the expression of sexually differentiated patterns of behaviours during the breeding cycle, and provide the first mapping of tyrosine hydroxylase immunoreactive (Til-ir) structures in the ring dove brain. Quantitative analysis revealed increased TFJ-ir cells, in male and female brooding doves, in the nuclei periventricularis magnocellularis, dorsomedialis anterior thalami, pretectalis medialis; and in the nucleus dorsomedialis posterior thalami in female brooding birds. This confirms that increases in dopamine activity during the brooding period are exhibited in regions integrating neuroendocrine and sensory information to mediate the expression of parental defence behaviours. Immunofluorescence studies revealed no co-localisation of progesterone receptor (PR-fr) in TM-fr cells, but demonstrated the presence of TH-fr terminals in axosomatic contact with PR-fr-containing cells in the preoptic region, which may enable dopamine activation of the progesterone receptor, via the Dl receptor. A collaborative study with the University of Hiroshima, demonstrated increased progesterone concentrations in the diencephalon of male brooding doves compared with non-breeding male doves. Measurement of 3[3-HSD enzymatic activity confirmed the synthesis of progesterone in the ring dove diencephalon. This may be sexually differentiated and mediated by proliferating glial cells, under the influence of VIP and prolactin. Primary glial cell culture techniques established the presence of PR-fr in cultured ring dove brain cells. These studies suggest that nest defence behaviour in male and female ring doves may be mediated by differentially elevated levels of centrally acting progesterone, arising as a consequence of increasing dopante activity in the preoptic area. The possibility of progesterone inhibition of y-aminobutyric acid (GABA) activity, to disliThibit dopamine neuronal activity during incubation and brooding, and enable the expression of defensive behaviours is discussed.

The newborn screening for congenital hypothyroidism (CR) started in the West in the sixties. The guidelines for screening were introduced in the majority of western countries some 30 years ago and were adapted in 1997 by the World Health Organization. The United Arab Emirates (UAE) started newborn screening for CH in 1998 and was considered one of the leading countries in the Middle East to apply this programme nationwide. Before newborn screening for CH in the UAE, little was known about the epidemiology of the disease in this part of the world which shares the same epidemiological pattern of the Gulf region and the Middle East This nationwide study investigated the epidemiological pattern of CH in the UAE in terms of assessment of biological and environmental components and their significance in the relatively increased incidence of the disease in this community compared to the worldwide incidence (1:30004000). This study employed radioimmunoassay technique used by the newborn screening programme to measure the capillary Thyroid Stimulating Hormone (TSR) for all newborns at the week of age. In addition, chemical and radiological techniques were employed to screen for positive cases. Firstly, cases detected have been studied in terms of prevalence of the disease in the UAE in relation to other parts of the world and the definition of the epidemiological components and its association to the prevalence of the disease. The study included the investigation of the genotypic pattern of congenital hypothyroidism in the UAE among certain cases with familial dyshormonogesis phenotype. The results show high incidence of the disease compared to the worldwide incidence and also it showed a specific epidemiological pattern. Secondly, the study employed the data obtained in newborn screening for CH in a longitudinal study of TSR pattern of the population and its use to monitor the iodine uptake of this population. This part of study also studied other important implications of the TSR pattern which included the TSR surge and the prevalence of sub clinical cases in which TSH is the main monitor. Thirdly, the study evaluated the controversial issues in the newborn screening programme in the preanalytic and post-analytic phases of the programme. The role of incorporation of the pre and post analytical quality control of the programme in reduction of the morbidity of the disease. Nevertheless, this study provides an overview for the epidemiological pattern of congenital hypothyroidism in the UAE and forms a basic epidemiologic background for further detailed studies that would focus on the clinical aspect and prognostic outcome of the disease. It may be concluded that the clinical picture of congenital hypothyroidism has changed dramatically since newborn screening was instituted in the UAE. Population-based registers and linked-databases can provide very useful information for evaluating screening programmes, and extending current knowledge of the epidemiology of congenital hypothyroidism. This is the first epidemiological study of CH in the UAE in which data from population-based registries were linked, the epidemiologic patterns and associated factors are more representative. The study delineates the significantly increased incidence of congenital hypothyroidism compared to the universal incidence and the clear correlation of this incidence with certain risk factors. Some of these are local which pertain to this area of the world and end in constituting this specific epidemiological pattern.

The susceptibility of human lungs to carcinogens depends on the metabolic balance between activation and detoxification pathways, though for the tumour to develop depcnds on activation of cell immortalisation pathway. The correlation of these pathways has not been reported. The present study described the correlation in transcription of genes of two phases of drug metabolism pathways and immortalisation pathway in four lung cell lines namely; a normal lung cell line (CDD32Lu), alveolar adenocarcinoma (A549), pleural adenocarcinoma (1-1460), and a drug resistance large cell carcinoma (COR-L23/5010). The levels of transcripts of Phase I (CYPL4I, CYPIA2 and CYP2EI), phase II (GSTMJ) and immortalisation (hTERT) genes were investigated. There was evidence suggesting that the transcription of CYPJAI, and CYP/A2 is of cell specific since CYPIAJ transcribed in the A549 eell line only, while CYPIA2 was transcribed in the H460 cell line. The present study validates the ability of CYPIA2 to be expressed in cell line. Moreover, the present study showed abundant expression of CYP2E/ and GSTMJ mRNA in normal and lung cancer cell lines suggesting that these genes may play no active role in lung carcinogenesis. In addition, the transcription level of immortalisation gene (hTERT) and telomerase activity was determined and observed in the A549 cell line only. The novel finding of this research is the cb-transcription of CYPJAJ and JITERT in the A549 cell line. The co-transcription was further analysed by induction of CYPJAJ in all cell lines with the AhR ligands TCDD and 3-MC. The finding reveals the existence of CYPIAI and hTERT co-transcription. Despite the fact that transcription of CYPJAI was observed CYP1A1 activity was not detected even after cell treatment with CYP1A1 inducers. This was possibly due to scarcity of CYP1A! and limited level of haem in the extrahepatic tissue. This study demonstrated a novel basal and induced co-transcription of CYP1AJ and hTERT. The regulation of co transcription was analysed by silencing CYPIAJ using siRNA technology and observing hTERT knockdown. Silencing of CYP1AI was subsequently downregulate hTERT transcription and reduces cells viability. The mechanism of co-transcription was investigated to rule out the involvement of suggested AhR signalling pathway. This was carried out by determining the level of mRNA expression of those genes, which their proteins were involved in the AhR signalling pathway. The results obtained suggest the role of the AhR signalling pathway in the co-transcription of CYPJAJ and hTERT. The data obtained from gene knockdown experiments revealed silencing of CYPJAJ alters hTERT expression and cell proliferation. The present study suggests that siRNA technology can be used as a reliable tool for the validation of co-transcription. Moreover, the concomitant silencing of CYPJAJ and hTERT and inhibition of cells proliferation not only validate the co-transcription but also a valuable finding to be considered as a novel therapeutic target, which may contribute to management of lung cancer. The transcription of CYPIAJ and hTERT has been identified as a cancer risk marker in a diverse range of cancers, the data of the present study suggests the use of CYPJA] 5iRNA as optional gene therapy in cancer management, where CYPJAJ plays a major risk.