Micronucleus Assay in preneoplastic injuries of cervical cancer

Alcantara-Quintana Luz Eugenia; Teran-Figueroa Yolanda; Ortiz-Valdez Julio Alejandro; Gallegos-Garcia Veronica

Volume : VII, Issue : IX, September - 2018

Micronucleus Assay in preneoplastic injuries of cervical cancer

Alcantara Quintana Luz Eugenia, Teran Figueroa Yolanda, Ortiz Valdez Julio Alejandro, Gallegos Garcia Veronica

Abstract :

Introduction: Cervical cancer ranks fourth among the ten leading global causes of death,preinvasive lesions and invasions of the cervix are a public health problem. In the state of San Luis Potosi, Mexico, it is common to see women between 20 and 30 years old.Is necessary found biomarkers in preneoplastic injuries, for that reason we evaluatethe genotoxicrisks (observed as DNA damages) by Micronucleus (MN) Assay in lymphocytes of peripheral blood and exfoliated epithelial cervical cells.

Aim:To identify the occurrence of MN in preneoplastic lesions and to find the correlation between MN and preneoplastic lesions at the time of diagnosis (zero time), 3, 6 and 12 months after the treatment in lymphocytes andexfoliated epithelial cervical cells.

Materials and Methods: A total of 160 females were included in the study and visual examination of the cervix was done. Based on the examination:four groups were formed: A-normal cervix (n=40); B-CIN I (cervical intraepithelial neoplasia I; n=40); C-CIN II (cervical intraepithelial neoplasia II, n=40); and D-CINIII (cervical intraepithelial neoplasiaIII, n=40).Blood and cervix cells sample was collectedafter getting the informed consent.After 3, 6 and 12 months of treatment, samples of epithelium and blood were also taken.Then were cultured, with RPMI andDMEM-F-12 supplemented and incubated at 37 � C and 5% CO₂ for five daysin 24-well plates. Slides were prepared from the pellet, were fixed in methanol and glacialaceticacidfixative 1:1andstainedwithPAS-PAP stain modified.Thepresenceof MNwasconfirmedunderoilimmersion(100X),observationswere recorded. Two hundredcellswererecordedineach patientfromtheslidespreparedandtheincidenceofmicronucleus was recorded with IMAGE PRO PLUS software and the collected data was subjected to ANOVA test with GraphPad Prism v.7.

Results: ANOVA test showed us significative differences between the mean MN count of healthy individuals and the mean of preneoplastic lesion stage, CIN I, CIN II, and CINIII at zero time. The same behavior was observed at longer time, twelve months.The Group B (CIN I), C(CIN II) and D (CIN III) ases had significant MN count at three, six and twelve months compared with healthy individuals (Group A). Nevertheles we not found significative differences when compared lymphocytes and epithelial cervical cells.In other results, was obtained that on average in lymphocytes there was a presence of 3.5 % of micronuclei and epithelial cells of 4.5% in healthy women, CIN I 21 vs 22%, CINII 39 vs 36 % and CINIII 66.5 vs 68%. It was shown that there is no statistically significant difference between counts in lymphocytes and epithelial cells. Therefore the lymphocytes is the better option for MN assay.

Conclusion: A statistically significant MN count was seen in the different stages of preneoplastic lesionof cervix. MN assay is an easy, non-invasive, cost-effective method and can be used as a screening test for a largepopulation. The micronucleus test would be a useful tool in the diagnosis of cancer supported by other diagnostic techniques of genotoxic damage.