Prevalence of micronuclei in exfoliated uterine cervical cells from patients with risk factors for cervical cancer

High expression level of CXCL1/GROα is linked to advanced stage and worse survival in uterine cervical cancer and facilitates tumor cell malignant processes

Background

CXCL1 belongs to a member of the ELR + CXC chemokine subgroups that also known as GRO-alpha. It has been recognized that several types of human cancers constitutively express CXCL1, which may serve as a crucial mediator involved in cancer development and metastasis via an autocrine and/or paracrine fashion. However, the expression pattern and clinical significance of CXCL1 in human uterine cervix cancer (UCC), as well as its roles and mechanisms in UCC tumor biology remains entirely unclear.

Methods

The expression and clinical significance of CXCL1 in UCC tissues was explored using immunohistochemistry and bioinformatics analyses. The expression and effects of CXCL1 in HeLa UCC cells were assessed using ELISA, CCK-8 and transwell assays. Western blotting experiments were performed to evaluate the potential mechanism of CXCL1 on malignant behaviors of HeLa UCC cells.

Results

The current study demonstrated that CXCL1 was expressed in HeLa UCC cells, PHM1-41 human immortalized cervical stromal cells, as well as cervical tissues, with UCC tissues having an evidently high level of CXCL1. This high level of CXCL1 in cancer tissues was notably related to poor clinical stages and worse survival probability, rather than tumor infiltration and patient age. In addition, CXCL1 expression was extremely correlated with CCL20, CXCL8 and CXCL3 cancer-associated chemokines expression. In vitro, the growth and migration abilities of HeLa cells were significantly enhanced in the presence of exogenous CXCL1. Gain-function assay revealed that CXCL1 overexpression significantly promoted growth and migration response in HeLa cells in both autocrine and paracrine manners. Finally, we found that CXCL1 overexpression in HeLa cells influenced the expression of ERK signal-related genes, and HeLa cell malignant behaviors derived from CXCL1 overexpression were further interrupted in the presence of the ERK1/2 blocker.

Conclusion

Our findings demonstrate the potential roles of CXCL1 as a promoter and a novel understanding of the functional relationship between CXCL1 and the ERK signaling pathway in UCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09749-0.

KLK5 is associated with the radioresistance, aggression, and progression of cervical cancer

OBJECTIVE

The role of kallikrein-related peptidase 5 (KLK5) has been studied in several diseases, including skin and ovarian cancers. However, its role in cervical cancer remains unclear, particularly in regulating the radiation resistance and growth of cervical cancer cells. Radiation resistance of cervical cancer is associated with local recurrence, distant metastasis, and reduced survival.

METHODS

We first analyzed radiotherapy-naive samples and relevant clinical data from patients with cervical cancer who received radiotherapy without surgery or other antitumor treatment from 2014 to 2016. Subsequently, biopsied tissues, in vitro cells, and transplanted tumors in nude mice were investigated.

RESULTS

Gene sequencing and clinical data analysis showed that KLK5 overexpression was associated with a poor prognosis post-radiotherapy. In in vitro cell and tumor transplantation experiments, KLK5 overexpression significantly increased radiation resistance. However, downregulating KLK5 expression increased radiosensitivity.

CONCLUSION

Our results confirm that KLK5 is vital to the radioresistance of cervical cancer, and provide a new target and marker for the treatment of radioresistance in cervical cancer.

Use of micronucleus assays for the prediction and detection of cervical cancer: a meta-analysis

Cervical cancer (CC) is the fourth most common cancer in women; the survival rates depend strongly on its early detection. The Pap test is the most frequently used diagnostic tool, but due to its limited sensitivity/specificity, additional screening tests are needed. Therefore, we evaluated the use of micronucleus (MN) assays with cervical cells for the prediction and diagnosis of CC. MN reflects structural and numerical chromosomal aberrations. A search was performed in Pubmed, Scopus, Thomson ISI and Google Scholar. Subsequently, meta-analyses were performed for different grades of abnormal findings in smears and biopsies from patients which were diagnosed with CC. Results of 21 studies in which findings of MN experiments were compared with data from Pap tests show that higher MN frequencies were found in women with abnormal cells that are indicative for increased cancer risks. MN frequency ratios increased in the order inflammation (2.1) < ASC-US and ASC-H (3.3) < LGSIL (4.4) < HGSIL (8.4). Furthermore, results are available from 17 investigations in which MN were scored in smears from patients with neoplasia. MN rates increased with the degree of neoplasia [CIN 1 (4.6) < CIN 2 (6.5) and CIN 3 (10.8)] and were significantly higher (8.8) in CC patients. Our meta-analysis indicates that the MN assay, which is easy to perform in combination with Pap tests, may be useful for the detection/prediction of CC. However, standardization (including definition of the optimal cell numbers and stains) and further validation is necessary before the MN test can be implemented in routine screening.

Micronucleus assay for predicting side effects of radiotherapy for cervical cancer

Radiotherapy (RT) is an important treatment for cervical cancer. The quality of life of patients undergoing RT may be compromised during and following treatment by nausea, diarrhea, vomiting, burns, erythema and fistula. Cytokinesis-block micronucleus (CBMN) assays may be useful for predicting adverse effects of RT for cancer. The CBMN test is easy to perform and is reproducible for screening subjects exposed to ionizing radiation. We investigated the use of the frequency of micronuclei (MN) from peripheral blood samples, irradiated in vitro, as a possible biomarker to predict the side effects of RT in patients with cervical cancer. We used 10 patients with cervical cancer receiving RT and chemotherapy. We found a strong relation between the frequency of MN and the appearance of acute side effects of RT for cervical cancer. We suggest that the methodology presented here may be useful for predicting side effects of RT for patients affected by cervical cancer and who have undergone chemotherapy.

Smoking causes induction of micronuclei and other nuclear anomalies in cervical cells

INTRODUCTION

Smoking is an independent cause of cervical cancer, which is the 4th most common malignancy in women. It is currently not known if tobacco consumption causes chromosomal damage (which is a hallmark of human cancer) in cervical cells and if age and the hormonal status have an impact on tobacco induced genetic instability in the cervix.

METHODS

We conducted a study with pre- and post-menopausal women smokers and never-smokers (25/group). Smokers consumed 30 light/medium cigarettes/day and were matched with the non-smoking group. Cervical cells were analyzed for induction of micronuclei (MN) which are caused by structural/numerical chromosomal aberrations; additionally, other nuclear anomalies reflecting genomic instability and cytotoxicity were scored. Furthermore, the frequencies of basal cells were recorded which reflect the mitotic activity of the mucosa.

RESULTS

MN and other abnormalities were increased in both groups of smokers. The effects were most pronounced in postmenopausal smokers (i.e. 2-fold higher) compared to premenopausal smokers. Also the number of basal cells (indicative for cell proliferation) was clearly enhanced in older women. Tar and nicotine had no detectable impact on chromosomal damage but a clear association with pack-years was observed.

CONCLUSIONS

Smoking increased chromosomal instability, cytotoxicity and induced cell divisions in cervical mucosa cells of pre- and post-menopausal women. The effects were more pronounced in the latter group indicating a higher risk for diseases (including cancer) that are causally related to DNA damage.

Micronuclei and Their Association with Infertility, Pregnancy Complications, Developmental Defects, Anaemias, Inflammation, Diabetes, Chronic Kidney Disease, Obesity, Cardiovascular Disease, Neurodegenerative Diseases and Cancer

Micronuclei (MN) are a strong cytogenetic indicator of a catastrophic change in the genetic structure and stability of a cell because they originate from either chromosome breaks or whole chromosomes that have been lost from the main nucleus during cell division. The resulting genetic abnormalities can to lead to cellular malfunction, altered gene expression and impaired regenerative capacity. Furthermore, MN are increased as a consequence of genetic defects in DNA repair, deficiency in micronutrients required for DNA replication and repair and exposure to genotoxic chemicals and ultraviolet or ionising radiation. For all of these reasons, the measurement of MN has become one of the best-established methods to measure DNA damage in humans at the cytogenetic level. This chapter is a narrative review of the current evidence for the association of increased MN frequency with developmental and degenerative diseases. In addition, important knowledge gaps are identified, and recommendations for future studies required to consolidate the evidence are provided. The great majority of published studies show a significant association of increased MN in lymphocytes and/or buccal cells with infertility, pregnancy complications, developmental defects, anaemias, inflammation, diabetes, cardiovascular disease, kidney disease, neurodegenerative diseases and cancer. However, the strongest evidence is from prospective studies showing that MN frequency in lymphocytes predicts cancer risk and cardiovascular disease mortality.

Association between cervical lesion grade and micronucleus frequency in the Papanicolaou test

The aim of this study was to evaluate the association between the frequency of micronuclei (MN) and the cellular changes detected in the conventional Papanicolaou test. One hundred and seventy-four Papanicolaou test smears with cellular changes were examined. MN screening was done in cytopathological smears by counting 1,000 cervical cells in a light microscope. MN frequencies were significantly higher in the group with cellular changes compared to the control group (p < 0.001). The mean MN frequencies were 0.95 ± 1.12 (mean ± SD) in the control group (n = 223), 2.98 ± 1.20 in individuals with atypical squamous cells of undetermined significance (ASC-US) (n = 50), 4.04 ± 1.45 in cervical intraepithelial neoplasia (CIN) I (n = 52), 5.97 ± 1.83 in CIN II (n = 30), 7.29 ± 1.55 in CIN III (n = 17) and 8.64 ± 1.55 in invasive cancer (n = 25). These findings suggest that MN monitoring should be included as an additional criterion for the early detection of cytogenetic damage in routine examinations. This monitoring should be done in the same smear as used for cytopathological examination. More specific and systematic studies are necessary to confirm this proposal.

Association between human papillomavirus (HPV) DNA and micronuclei in normal cervical cytology

The aim of the present study was to investigate the association between HPV-DNA and micronucleus (MN) frequency in women with normal cervical cytology. A total of 158 normal cervical smears were analyzed cytologically. The HPV genome was amplified using the GP5+/bioGP6+ consensus primers. HPV-DNA of high-risk types 16, 18, 31, 33, 39, 45 and 59 were also investigated. Of the 158 samples, 20 (12.7%) and 47 (29.7%) were positive for HPV-DNA and MN, respectively. Evidence for MN was found in 11 out of 20 (55%) HPV-DNA positive samples and in 36 out of 138 (26.1%) HPV-DNA negative ones. MN presence was significantly higher in HPV-DNA positive samples (p = 0.016). On the other hand, the absence of MN observed in a considerable number of HPV-DNA negative samples (102) may be of great value in predicting the absence of HPV. The mean age of HPV-DNA positive women (34.2 ± 12.6) was significantly lower than the mean age of HPV-DNA negative women (43.9 ± 13.7) (p = 0.003). Infection by one or multiple HPV types was found in 11 out of 20 (55.0%) and 9 out of 20 (45.0%) samples, respectively. The evaluation of MN using cervical smears collected for cytology tests could, thus, be used as additional information to monitor a population’s exposure to HPV.

Significance of micronucleus in cervical intraepithelial lesions and carcinoma

Background:

The micronuclei (MNi) test on exfoliated cells has been successfully used to screen population groups at risk for cancers of oral cavity, urinary bladder, cervix and esophagus. Their frequency appears to increase in carcinogen-exposed tissues long before any clinical symptoms are evident. There are only limited numbers of studies on MN scoring in cervical pre-neoplastic and neoplastic conditions.

Aims:

To compare the micronucleus (MN) score in the whole spectrum of cervical lesions including normal, inflammatory, abnormal squamous cells of undetermined significance (ASC-US), abnormal squamous cells cannot exclude HSIL (ASC-H), low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL) and invasive cancer (IC) and to evaluate the role of MN as a biomarker in different pre-neoplastic and neoplastic lesions.

Materials and Methods:

A total of 221 slides, comprised of normal (32), inflammatory (32), ASC-US (31), ASC-H (31), LSIL (32), HSIL (31) and IC (32), were studied. All the cases were reviewed by two pathologists independently. Histopathological correlation was done in a few cases of ASC-US, ASC-H, HSIL and IC which were available in the department. Two observers separately and independently counted the number of micronucleated cells per 1,000 epithelial cells in oil immersion magnification and were expressed as MN score per 1,000 cells.

Results:

The mean MN scores ± SD in normal, inflammatory, ASC-US, ASC-H, LSIL, HSIL and IC cases of cervical lesions were 0.84±0.68, 1.06±0.84, 3±0.73, 4.78±1.43, 4.06±1.13, 8.03±1.64 and 10.5±2.01, respectively. MN scores of IC and HSIL were significantly high compared to normal (P<0.000), inflammatory (P<0.000), ASC-US (P<0.000), ASC-H (P<0.000) and LSIL (P<0.000) group (analysis of variance test). LSIL showed significant difference with the normal (P<0.000), inflammatory (P=0.001), ASC-US (P=0.028), HSIL (P<0.000) and IC (<0.000), but not with the ASC-H (P=0.64) group.

Conclusions:

MN scoring on the epithelial cells of cervix could be used as a biomarker in cancer screening. This is an easy, simple, reliable, reproducible and objective test which can be performed on routinely stained pap smears.

Micronucleus scoring in liver fine needle aspiration cytology

OBJECTIVE

This study evaluated the role of the micronucleus (MN) in liver fine needle aspiration (FNA) cytology.

METHODS

Histological features of 75 cases of hepatocellular carcinoma (HCC), of which 25 were well differentiated, 37 moderately differentiated and 13 poorly differentiated, and 58 benign hepatic lesions (total, 133 cases) were correlated with MN expression observed in FNA smears reported as benign (n =40), atypical (n = 14), suspicious (n = 30) and malignant (n =49).

RESULTS

Stepwise increases in the MN score (0.4 ± 0.6, 1.2 ± 1.3, 6.3 ± 4.2 and 14.8 ± 8.8) correlated with the degree of cytological abnormality: benign, atypia, suspicious and malignant, respectively. The mean MN scores for well-, moderately and poorly differentiated HCC were 5.4 ± 2.2, 11.5 ± 4.5 and 24.9 ± 9.1, respectively, which was significantly different between malignant and suspicious (P < 0.0001), between suspicious and atypical (P= 0.008) but not between atypical and benign. The MN scores differed significantly between all degrees of differentiation of HCC and between the HCC and benign hepatic lesions (P < 0.0001). High sensitivity, specificity and accuracy of liver FNA for diagnosing HCC (96%, 98%, and 96%, respectively) were obtained at a cutoff of three for the MN score.

CONCLUSIONS

The MN score is an effective HCC biomarker and has a good potential use as an ancillary tool for diagnosing HCC using FNA cytology.