Genotoxic properties of XLR-11, a widely consumed synthetic cannabinoid, and of the benzoyl indole RCS-4

Aim of this study was the investigation of the genotoxic properties of XLR-11 [1-(5-fluoropentyl)-1H-indol-3-yl](2,2,3,3-tetramethylcyclopropyl)methanone, a widely consumed synthetic cannabinoid (SC), and of the benzoyl indole RCS-4 (4-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone). We characterized the DNA-damaging properties of these drugs in different experimental systems. No evidence for induction of gene mutations was detected in bacterial (Salmonella/microsome) tests, but clear dose-dependent effects were found in in vitro single cell gel electrophoresis (SCGE) assays with human lymphocytes and with buccal- and lung-derived human cell lines (TR-146 and A-549). These experiments are based on the determination of DNA migration in an electric field and enable the detection of single- and double-strand breaks and apurinic sites. Furthermore, we found that both drugs induce micronuclei which are formed as a consequence of chromosomal aberrations. The lack of effects in SCGE experiments with lesion-specific enzymes (FPG, Endo III) shows that the DNA damage is not caused by formation of oxidatively damaged bases; experiments with liver enzyme homogenates and bovine serum albumin indicate that the drugs are not converted enzymatically to DNA-reactive intermediates. Furthermore, results with buccal- and lung-derived human cells show that gaseous treatment of the cells under conditions which reflect the exposure situation in drug users may cause damage of the genetic material in epithelia of the respiratory tract. Since DNA instability is involved in the etiology of cancer, these findings can be taken as an indication that consumption of the SCs may cause tumors in the respiratory tract of consumers.

Relationship between HbA1c and cancer in people with or without diabetes: a systematic review

AIM

To identify the relationship between HbA1c and cancers in people with or without diabetes.

BACKGROUND

Cancer is a major public health problem, accounting for 8.2 million deaths worldwide in 2012. HbA1c level has been associated with the risk of developing certain cancers, although the existing evidence is conflicting.

METHODS

EMBASE, MEDLINE, CINAHL and the Cochrane Library were searched. Eligible articles included randomized controlled trials, cohort studies, case-control studies, systematic reviews and meta-analyses. Participants of either sex, with or without Type 1 or 2 diabetes, were included. The studies were assessed using the Scottish Intercollegiate Guidelines Network (SIGN) criteria by two independent assessors. No meta-analysis was performed because of the heterogeneity of results.

RESULTS

A total of 19 studies from 1006 met the inclusion criteria, of which 14 were cohort studies and five were nested case-control studies. Eight studies investigated outcomes for all cancer sites. Four of these studies reported that higher HbA1c levels were associated with higher incidence and/or mortality risk for all cancers. One study observed a U-shaped relationship between HbA1c and cancer incidence and mortality. Increasing HbA1c levels were associated with increasing risk of developing colorectal, pancreatic, respiratory and female genital tract cancers. No increased risk was observed for breast cancer, gastrointestinal or urological malignancies.

CONCLUSION

HbA1c appears to be associated with cancer incidence and/or cancer mortality, but further studies are needed to fully understand the complex relationship between HbA1c and cancer.

DNA methylation biomarkers in biological fluids for early detection of respiratory tract cancer

Cancers of the respiratory tract (lung and head and neck) share common aetiologies, risk factors and molecular characteristics. Epigenetic reprogramming is one of the hallmarks of cancer and DNA methylation is currently the best-studied form. There are a number of characteristics of DNA methylation, which seem advantageous in biomarker development. Early detection is still an unmet clinical care need, which guarantees to significantly reduce the mortality of patients with respiratory cancers. The application of such biomarkers in biological fluids being sampled in everyday clinical practice is a long-term demand. In this review we summarise the current literature on DNA methylation detection in bronchial washings, sputum, saliva, plasma and serum and discuss the potential of their clinical implementation. We also discuss important aspects of biomarker development and validation pointing to the appropriate route for a biomarker to reach clinical standards.

Overexpression of Eag1 potassium channels in clinical tumours

Background

Certain types of potassium channels (known as Eag1, KCNH1, Kv10.1) are associated with the production of tumours in patients and in animals. We have now studied the expression pattern of the Eag1 channel in a large range of normal and tumour tissues from different collections utilising molecular biological and immunohistochemical techniques.

Results

The use of reverse transcription real-time PCR and specifically generated monoclonal anti-Eag1 antibodies showed that expression of the channel is normally limited to specific areas of the brain and to restricted cell populations throughout the body. Tumour samples, however, showed a significant overexpression of the channel with high frequency (up to 80% depending on the tissue source) regardless of the detection method (staining with either one of the antibodies, or detection of Eag1 RNA).

Conclusion

Inhibition of Eag1 expression in tumour cell lines reduced cell proliferation. Eag1 may therefore represent a promising target for the tailored treatment of human tumours. Furthermore, as normal cells expressing Eag1 are either protected by the blood-brain barrier or represent the terminal stage of normal differentiation, Eag1 based therapies could produce only minor side effects.

[Epidemiologic and radiobiologic features of neoplasms in respiratory and gastrointestinal tracts among patients who had occupational contact with uranium]

Morbidity structure among workers engaged into main production of nuclear industry had prevailing lung cancer (1.93 per 1,000), gastric carcinoma (1.09) and colon cancer (0.72). The lung cancer patients demonstrated the highest concentrations of uranium in lung tissue (0.8313 g/g) and liver tissue (0.3548 g/g); those with gastric carcinoma and of reference group--in lung radix nodes (0.1855 and 0.3685 g/g respectively).

Retinoid receptor cross-talk in respiratory epithelium cancer chemoprevention

The rationale for using retinoids in the prevention of respiratory epithelium cancers is based on their ability to coordinately regulate differentiation, proliferation and apoptosis. The complex retinoid signaling pathways and their cross-reactions are modulated by multiple mechanisms that are gradually being elucidated. It is possible that significant molecular changes take place during the very early stages of respiratory epithelial carcinogenesis, which enable cancer cells to escape apoptosis and result in unimpeded proliferation. Here, we propose that a "switch on/off" model dictates the cross-talk between retinoid receptors and other signal transducing pathways during respiratory epithelium carcinogenesis. This model might contribute to the development of novel selective retinoids and their clinical evaluation in combinatorial chemopreventive strategies.

Mucin biosynthesis: epidermal growth factor downregulates core 2 enzymes in a human airway adenocarcinoma cell line

Enzymes which exhibit core 2 beta1,6 N-acetylglucosaminyltransferase (C2GnT) activity play important roles in physiologic processes including the inflammatory response and immune system function, and C2GnT activity is regulated during processes, such as T cell activation and cellular differentiation. In this study, we have examined the regulation of C2GnT activity in the H292 airway epithelial cell line by epidermal growth factor (EGF), which has been previously shown to upregulate expression of the airway mucin MUC5AC in this cell line. We found that EGF suppressed C2GnT activity in a time- and dose-dependent fashion, and also suppressed core 4 beta1,6 N-acetylglucosaminyltransferase (C4GnT) activity. Consistent with the suppression of C4GnT activity, Northern blotting results showed that EGF preferentially inhibited the M isoform of C2GnT, which forms core 2, core 4, and blood group I beta1,6 branched carbohydrate structures, while the L isoform, which forms only the core 2 structure, was only modestly affected. Furthermore, EGF treatment resulted in a shift in the carbohydrate structure of FLAG-tagged MUC1 expressed in the cells from core 2-based toward core 1-based structures, consistent with the inhibitory effects of EGF on C2GnT. Transforming growth factor alpha mimicked the effect of EGF on C2GnT, implicating the EGF receptor (EGF-R) in C2GnT suppression, and the EGF-R tyrosine kinase inhibitor AG1478 blocked C2GnT suppression, confirming the role of EGF-R in the inhibition of C2GnT expression. Also, PD98059, a specific inhibitor of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK)1/2 in the Ras-mitogen-activated protein kinase pathway, completely blocked the EGF suppressive effect, suggesting possible involvement of the Ras-mitogen-activated protein kinase pathway in EGF-mediated downregulation of C2GnT. The results of this study suggest that exposure of airway cells to EGF may result in remodeling of mucin carbohydrate structure, potentially altering the biological properties of the cells.

Specificity of MOC-31 and HBME-1 immunohistochemistry in the differential diagnosis of adenocarcinoma and malignant mesothelioma: a study on environmental malignant mesothelioma cases from Turkish villages

Histological diagnosis of malignant mesothelioma (MM) and differentiation from adenocarcinoma is often difficult. A number of clinical, radiologic, histologic and histochemical criteria have been used as diagnostic aids, but most cases cannot be readily classified on the basis of these characteristics. In recent years, a panel of immunohistochemical anti-bodies have been increasingly applied for the differential diagnosis of these two tumors. MOC-31 has been recently used as specific for adenocarcinomas while reacting with a minimal number of benign and malignant mesothelial proliferations, and HBME-1 has also been presented as a mesothelial cell marker. In this study, we aimed to show the importance of these two antibodies among the environmental MM cases from Southeastern Turkey. Fifty five cases of MM and twenty adenocarcinomas were included in this study. Histochemical (PAS, PAS-D, mucicarmine) and immunohistochemical (Keratin, EMA,CEA, MOC-31, HBME-1) stains have been performed on each case. Keratin was positive in all cases. EMA stained 50 of 55 MM and all the adenocarcinoma cases. According to our results, dPAS, mucicarmen, CEA and MOC-31 positivity was statistically significant in the diagnosis of adenocarcinoma whereas HBME-1 was demonstrable in most MM cases (52/55) and 11 adenocarcinoma cases. This study confirmed that in the diagnostic distinction between MM and adenocarcinoma, immuno-histochemistry is an important diagnostic tool, however, a panel of antibodies must be used rather than any single antibody. HBME-1 should be included in this panel; MOC-31 can be used where CEA is not available or to doublecheck the reactivity of this antibody.

Morphometric characteristics of cell proliferation and p53 expression in development of experimentally induced respiratory tumors

OBJECTIVE

To study, under controlled conditions, the applicability of automated image analysis of immunohistochemical markers as an indicator of development and progression in tobacco component-induced tumors in the respiratory tract.

STUDY DESIGN

Amount, location, size, shape and intensity of staining of proliferating cell and p53 antigen in chemically induced precursors and squamous cell carcinoma of the hamster lung were determined by computer-assisted morphometry.

RESULTS

The total expression of proliferating cell nuclear antigen (PCNA) and p53 expression increased consistently during the formation of papillomas and squamous cell carcinomas of the larynx, trachea, bronchi and lungs. Individual preneoplastic cells in epithelial dysplasia expressed PCNA staining, increasing with increasing cell size and optical density, indicating antibody- staining intensity, in relation to the increased degree of cellular atypia. In malignant tumors, cell size decreased with decreasing differentiation, while antibody staining intensity remained unchanged. The increased alterations in cell shape and percent PCNA-positive cells observed in dysplastic epithelium and squamous cell carcinomas were statistically significant using Spearman's correlation coefficient. Squamous cell carcinomas consisted of two tumor cell populations with different cell shapes, and PCNA and p53 staining intensity. Altering measurement conditions-antibody threshold levels, size of measured area and repeating measurements-showed computer-assisted image analysis to give sensitive, reliable and consistent results.

CONCLUSION

Computer-assisted analysis of immunohistochemical staining showed high sensitivity and reproducibility; however, the results depended upon the method of study.

Topoisomerase alpha II, retinoblastoma gene product, and p53: potential relationships with aggressive behavior and malignant transformation in recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) has a juvenile aggressive form and an adult more indolent form. Most cases of RRP are cytologically benign; however, some undergo malignant transformation. At present, there are no known markers that help identify patients at risk for aggressive disease. We investigated by immunohistochemistry expressions of topoisomerase alpha II, MIB-1, p53, p21, E-cadherin, retinoblastoma (RB) gene protein product, HER-2/neu, and steroid hormone receptors in a case of juvenile respiratory papillomatosis with malignant transformation to determine whether these markers are associated with malignant transformation. Histologic examination of the pulmonary lobectomy specimen revealed well-differentiated squamous carcinoma and invasive papillomatosis. Increased staining was found in areas of invasive papillomatosis for topoisomerase alpha II, p53, and MIB-1, with highest labeling indices in areas of squamous carcinoma. Staining intensity for RB gene protein product showed gradual decline from benign papilloma (3+) and invasive papillomatosis (2+) to squamous carcinoma (0-1+). Expression of p21 was similar in benign papilloma and invasive papillomatosis but showed reduction in squamous carcinoma. Expressions of E-cadherin, HER-2/neu, and steroid hormone receptors did not appear to correlate with biologic behavior. Increased topoisomerase alpha II and p53 expression along with reduced RB gene protein product and p21 expression may serve as markers of transformation to invasive papillomatosis and squamous carcinoma.

Analysis of the DMBT1 gene in carcinomas of the respiratory tract

Loss of chromosome 10q is a critical step during the progression and metastasis formation of lung cancer. We recently defined 3 distinct regions of allelic imbalances and considered the DMBT1 gene at 10q25-q26 an interesting candidate for the most telomeric region. Therefore, we investigated DMBT1 in 25 cancer cell lines and 39 primary tumors of the respiratory tract. The analysis by RT-PCR and Northern blot hybridization revealed that the gene is expressed in all tumors and cell lines and diminished in the SCLC line H187, indicating that RT-PCR is critical when used as the single method for the evaluation of gene expression. No mutations were found by SSCP analysis of the cDNA and the partially known genomic sequence. Similarly, Southern blot hybridization was unable to detect homozygous deletions. Allelotyping of the markers D10S587, D10S1708 and D10S1723 located near or within the DMBT1 gene did not reach the peak incidence of the 3 minimally deleted regions that we recently defined. In summary, our data do not confirm previous findings reporting frequent loss of DMBT1 expression in lung cancer. However, they strengthen the notion that the responsible gene on chromosome 10q25-q26 mediating tumor progression and metastasis formation in respiratory tract cancer remains enigmatic.

Serum YKL-40: a new potential marker of prognosis and location of metastases of patients with recurrent breast cancer

YKL-40 is a recently discovered glycoprotein which is related in amino acid sequence to the chitinase protein family, but has no chitinase activity. Although the function of YKL-40 is presently unknown, the pattern of its expression by some tissues suggests that YKL-40 could function in tissue remodelling. The diagnostic features and relation to survival of serum YKL-40 have not been examined previously in human malignancies. In the present study YKL-40 was measured in serum obtained from 60 patients at the time that breast cancer recurrence was suspected. The median serum YKL-40 in patients with visceral or bone metastases was 328 and 157 micrograms/l, respectively and significantly higher compared to controls (99 micrograms/l, P < 0.001). Kaplan-Meier survival curves demonstrated that survival rates after 18 months were 24% for patients with high serum YKL-40 (> 207 micrograms/l = the 95 percentile of controls) and 60% for patients with normal serum YKL-40. The significance of the difference between the shorter survival of patients with high serum YKL-40 and the longer survival of patients with normal serum YKL-40 was high (P < 0.0009). When evaluated with other prognostic factors of survival after recurrence of breast cancer, serum YKL-40 and serum lactate dehydrogenase (LDH) were the most significant independent factors. The results indicate that determination of serum YKL-40 can be used as a prognostic marker related to the extent of disease and survival of patients with recurrence of breast cancer. In addition, the serum YKL-40 level may be of value in the follow-up of patients with breast cancer and in evaluating potential metastatic spread.

[Plasmacytomas of the upper respiratory tract]

Nine cases of plasmocytoma of the upper airways in the current biopsy material are studied over a three-year period (1991-1993). Initially, all nine cases are clinically diagnosed as neoplasms: hemangiofibroma--one, chondrosarcoma--one, suspected carcinoma--five, and unspecified diagnosis--two. "Plasmocytoma" diagnosis is made on the ground of histological investigation of the material, supported histochemically and electron-microscopically. Some diagnostic problems (differential diagnosis inclusive) are discussed, as well as issues relating to the clinical and morphological evolution of the disease, and predilected gender and age groups.

Carcinogen biomarkers related to smoking and upper aerodigestive tract cancer

Smoking is the major cause of upper aerodigestive tract cancers. Among the many constituents of tobacco smoke, polynuclear aromatic hydrocarbons and tobacco-specific nitrosamines are strongly implicated as causative factors for these cancers. The probability that these compounds will induce cancer in a given individual will depend on that person's ability to metabolically activate or detoxify them. Chronic production of DNA damage by these metabolically activated carcinogens is consistent with current concepts of carcinogenesis in which multiple genetic changes, such as activation of oncogenes or inactivation of tumor suppressor genes, appear to be critical. Chemopreventive agents which decrease the level of DNA damage should therefore decrease the risk for cancer. Biomarkers such as carcinogen-DNA adducts, carcinogen-hemoglobin adducts, and urinary metabolites of carcinogens will indicate the amount of metabolically activated carcinogen which may damage DNA in an individual and can therefore be used as an index of risk. Selected biomarkers are discussed in this paper. These biomarkers of internal dose have great potential for application in chemoprevention trials.

Solitary fibrous tumor of the upper respiratory tract. A report of six cases

We report six cases of a neoplasm that arose in the upper respiratory tract and had a histological appearance indistinguishable from that of solitary fibrous tumor of the pleura (SFT, so-called fibrous mesothelioma). The patients were adults who presented with nasal obstruction. The lesions lacked the characteristic features of other recognized neoplasms that occur in this region. The tumor cells were immunoreactive for vimentin but not for keratin. The occurrence of SFT in this location further supports the argument that SFT is a tumor of mesenchymal and not mesothelial origin. None of the tumors in this series had the histologic features of malignancy described for SFT in other locations, and there was no aggressive behavior in limited follow-up. Until more cases of SFT in unusual locations have been studied, we recommend that the same criteria used for assessing aggressiveness in SFT of the pleura be applied to them.

Primary malignant melanoma of the lower respiratory tract. Report of a case and literature review

The authors report a case of primary bronchial malignant melanoma, occurring in a 34-year-old woman presenting with persistent cough. At bronchoscopic examination, a polypoid mass was found to occlude the left mainstem bronchus. Biopsies showed a malignant epithelioid tumor resembling an atypical carcinoid. Histochemistry, electron microscopic study, and immunohistochemistry confirmed the diagnosis of melanoma. Physical examination and additional clinical history to exclude other possible primary sites were negative. The patient underwent thoracotomy with left pneumonectomy. Nineteen months after resection she was found to have a histologically similar tumor involving her left adrenal gland. Review of the literature shows that melanoma of the lower respiratory tract has been reported only in adults and has a tendency to present as a central polypoid growth that may be responsive to surgical resection.

Purified protein derivative induced cytotoxicity in carcinomatous and tuberculous pleurisy

We have found that natural killer (NK) cells were very active in pleural effusions containing Mycobacterium tuberculosis. Cytotoxicity against K562 and Raji was augmented when the mononuclear cells were cocultured for 18 hr with purified protein derivative (PPD) derived from M. tuberculosis culture supernatants. In pleural effusions of cancer patients, PPD-activated mononuclear cells were less cytotoxic than their counterparts in peripheral blood. However, in the same patients, interferon and interleukin-2 production was greater in pleural effusions than in peripheral blood. On the other hand, in tuberculosis patients there was no significant difference in cytotoxicity between peripheral blood and pleural effusion mononuclear cells, but the production of interferon and interleukin-2 was higher in pleural effusions than in peripheral blood. Neither group of patients consistently demonstrated a correlation between production of interferon or interleukin-2 in peripheral blood and cytotoxicity. Both PPD-induced cytotoxicity and the production of interferon and interleukin-2 were lower in mononuclear cells of carcinomatous than tuberculous pleural effusion. These results indicate that peripheral blood and pleural effusion mononuclear cells differ in cytotoxicity as well as in interferon and interleukin-2 production. Further, these activities also differ in tuberculous and carcinomatous pleural effusions.

An application of immunocytology to the analysis of the cell kinetics of upper respiratory and digestive tract squamous carcinoma

An antinucleoside immunofluorescence technique (ANIF) facilitated evaluation of labeling index (LI) from frozen sections of 36 upper respiratory and digestive tract squamous cancers (URDTS) from a group of 35 patients. There were 35 URDTS of the larynx, oral cavity, or pharynx and the LIs of this population ranged from 0-39.4%, (mean, 14.7%); 6% of URDTS (2 of 36) were not assessable by ANIF. The administration of nontherapeutic radioactive materials, the establishment of cell cultures, and perturbations in cell growth implicit in the removal of tumor from host prior to assessment are unnecessary in the application of this technique.

Variation of gamma glutamyl transpeptidase activity and lectin binding in the course of carcinogenesis of the respiratory tract epithelium

Gamma glutamyl transpeptidase (GGT) activity and fluorescein-labeled lectins Concanavalin A (Con A) and Ricinus communis-120 binding sites were studied in lesions produced by 7,12-dimethylbenz[a]anthracene during chemical carcinogenesis using syngeneic heterotopic rat tracheal transplants. Although all types of lesions showed positive GGT activity and lectin binding, prominent differences were observed between the different types of lesions. Compared with regular squamous metaplasia, dysplastic-neoplastic lesions showed much stronger reaction for GGT and lectins; normal and hyperplastic mucociliary epithelium showed intermediate reactions. Although the relationship between keratinization, cell surface changes, GGT activity and lectin binding are not completely clear, lectins seem to be good markers of dysplastic and neoplastic lesions of the respiratory tract epithelium.

DNA and its synthesis in individual tumor cells from human upper respiratory tract squamous cell carcinomas

Measurements of cytophotometric Feulgen DNA content and incorporation of 3H-thymidine were made in individual tumor cells from 58 patients with squamous cell carcinomas of the head-neck region. These measurements were correlated with a point ranking system for pathological grading for these types of tumors. Two of the parameters of the grading system, mode of invasion and nuclear polymorphism which had been found to be important factors in prognosis in clinical studies were correlated to the objective cellular DNA measurements. In 40 carcinomas, 10 were found to have a predominantly diploid distribution of DNA values, while the remaining 30 tumor values were either multiples of diploid or were aneuploid. Generally, tumors with low point rankings for individual morphological parameters tended to have diploid DNA values. Those tumors with higher DNA values usually had larger point rankings and more advanced clinical stage. When tumor cells from biopsies of 39 patients were studied by 3H-thymidine incorporation, no relevant connections between the labeling index and cellular DNA amounts, malignancy grading, or clinical stage were found.

Vitamin A and the susceptibility of respiratory tract tissues to carcinogenic insult

The influence of vitamin A on the development of chemically induced lung carcinomas in rats was investigated. Rats were maintained on low, "normal" and excess levels of retinyl acetate (RA). Respiratory tract-squamous carcinomas were induced by intratracheal injections of 3-methylcholanthrene (3-MCA). The carcinogen doses used ranged from 1.25 to 10.0 mg of 3-MCA. Serial sacrifices conducted during the first 20 weeks following carcinogen exposure showed that metaplastic lung nodules, presumed to be precursors of later appearing carcinomas, occurred earlier and at higher incidence in rats maintained on low levels of RA than in rats maintained on moderate or high levels of RA. The development of invasive pulmonary carcinomas was enhanced at all four carcinogen doses in rats receiving low levels of RA as compared to rats receiving moderate or high levels of RA. No consistent difference in lung cancer incidence existed between the groups receiving normal and high levels of RA. The data clearly show an increased susceptibility of vitamin A-deficient rats to develop chemically induced lung cancers. Possible mechanisms underlying this effect are discussed.