Environmental Carcinogenesis
Laboratory Home Overview:

This laboratory is dedicated to carcinogen hazard identification of chemicals/complex mixtures. It has identified the carcinogenic/co-carcinogenic potential of complex-mixture/mineral oil (Jute Batching Oil, both FDA & non-FDA type; cutting-oil, both fresh & used variety), solvent (cyclohexane), and pesticides (Mancozeb, Carbaryl, Captan, and Diuron) in vivo. Currently, evaluation of carcinogenic potential of ambient-air-ultra-fine-particulate-matter (UfPM), agrochemicals, and low-dose chromate using in vitro approach is in progress. Objectives also include cancer risk assessment of subjects exposed to carcinogenic chemicals. Exposure-/effect-estimates and adverse-health-effect of PAHs in ambient air, and Cr-VI in occupational environment have been reported. A case study suspecting role of mineral oil (JBO) in scrotal cancer in a Jute Mill worker has been reported. 

The section produced a total of 90 publications, 2 PhD theses, 1 Patent, and 2 Scientific Reports. The customers already benefited from the sectional-activity included Indian Jute Industries Research Association, Indian Oil Corporation, and World Bank.

  Major activities:

  • Identify carcinogen/co-carcinogen hazard of chemicals/complex-mixtures for safety evaluation.

  • Explore mechanism of chemical carcinogenesis.

  • Study genetic susceptibility, develop new biomarkers for to carcinogenesis detection, and estimate carcinogen-exposure/biological-effect for cancer risk assessment.

  • Evaluate cancer-chemopreventive/therapeutic potential of compounds of natural/synthetic origin

Highlights of Current Research:

  • Toxicogenomics of chromate carcinogenesis 
    Chromate compounds (containing Cr6+) are carcinogenic to humans. Cr-carcinogenesis-specific-biomarkers are being developed using toxicogenomics. Objective is to investigate gene-expression-profile of chromate-transformed cells in cell-culture and elucidate critical molecular targets altered at gene level by the toxicant. Transformation specific changes in genome are being characterized by sequence analyses of the genes showing altered expression and are being quantified using real time RT-PCR.

  • UfPM -carcinogen hazard identification 
    UfPM (size <100nm) is a constituent of RSPM. It comes from exhaust emissions and adsorbs genotoxic/carcinogenic- to-human chemical/ biological toxicants. UfPM content in urban ambient air is feared to be increasing presumably due to rapid urbaniza-tion, escalating road traffic density, incessant industrialization, and a consistent increase in use of diesel-powered engines. UfPM together with adsorbed atmospheric-aerosol deposit deep into lung, and escape phagocyte-clearance. The event ay trigger biological effects viz. inflammatory response, and oxidative stress locally conducive to carcinogene-sis risk. Chronic-exposure risk of airway epithelium, micro-alveoli epithelium and macrophages to UfPM and subsequently risk of carcinogenic changes is a possibility. Epidemiological studies have demonstrated association of SPM with chronic obstructive pulmonary disease; asthma; and lung cancer incidences. UfPM is therefore a credible threat to urban health. The carcinogen hazard of UfPM is being examined using in-vitro carcinogenesis approach.

  • Epigenetic basis of tumor development and its modulation by anticancer agents 
    DNA methylation is being studied using mouse lung tumor model. Inositols are being used as modulator of tumor development.

  • Gene methylation as marker for early detection of cancer 
    Genes of different pathways are being studied for their methylation status in mouse of exposed to tumorigen for different duration.

  • Single nucleotide polymorphism and nucleotide repeats for cancer susceptibility 
    This study is in cancer of cervix patients.

  • Basis of chemoprevention by newer compounds 
    Compounds of plant origin including algal origin are used for their effect on biochemical, molecular genetic epigenetic events at the different stages of tumor development in mouse.

Major Facilities available:

  • Carcinogen Hazard Identification including tumor-initiating/tumor-promoting, and complete carcinogenic potential using mouse skin and lung tumorigenesis test systems.

  • Exposure & effect estimates of human-carcinogen exposed-subjects.

  • Screening of cancer-chemopreventive/-chemotherapeutic potential of natural or synthetic compounds.

  Staff:
Dr. Sushil Kumar, Scientist F and Head 
Dr. (Ms) K.P. Gupta, Scientist E-II


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