{'fraction_non_alphanumeric': 0.027598896044158234, 'fraction_numerical': 0.017479300827966882, 'mean_word_length': 5.112359550561798, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Very early effect of DMBA and MNU on microRNA expression.

BACKGROUND
microRNA expression profile analysis provides evaluation of the early stages of carcinogenesis. This study focuses on early alteration of miRNA expression after treatment with different carcinogens.


MATERIALS AND METHODS
Mice were intraperitoneally injected with one dose of 7,12-dimethylbenz(α)anthracene (DMBA) and N-methyl-N-nitrosourea (MNU). The expression of miRNAs were analyzed 3 and 6 hours after the treatment, using quantitative real-time-polymerase chain reaction.


RESULTS
Underexpression of miR-34a and miR-155 were detected in the liver, spleen and kidneys at 3 and 6 hours after MNU treatment. In the lungs and kidneys, the expression of miR-21 was significantly elevated 6 hours after DMBA treatment, while in the liver, MNU induced higher expression levels of miR-21 at 3 and 6 hours compared to treatment with DMBA.


CONCLUSION
The different response of miRNAs to carcinogens emphasizes their possible role as potential epidemiological biomarkers in early phases of environmental tumorigenesis.