Epithelial-Mesenchymal Transition Associated with Head and Neck Squamous Cell Carcinomas: A Review

Head and neck squamous cell carcinomas (HNSCCs) are aggressive, recurrent, and metastatic neoplasms with a high occurrence around the world and can lead to death when not treated appropriately. Several molecules and signaling pathways are involved in the malignant conversion process. Epithelial-mesenchymal transition (EMT) has been described in HNSCCs, a major type of aggressive carcinoma. EMT describes the development of epithelial cells into mesenchymal cells, which depends on several molecular interactions and signaling pathways that facilitate mesenchymal conversion. This is related to interactions with the microenvironment of the tumor, hypoxia, growth factors, matrix metalloproteinases, and the presence of viral infections. In this review, we focus on the main molecules related to EMT, their interactions with the tumor microenvironment, plasticity phenomena, epigenetic regulation, hypoxia, inflammation, their relationship with immune cells, and the inhibition of EMT in the context of HNSCCs.

Leptospira infection in people in the city of Durango, Mexico: a cross sectional study

Objective

To determine the seroprevalence of Leptospira immunoglobulin (Ig)G and IgM antibodies and its association with the characteristics of the study population from the northern Mexican city of Durango, Mexico.

Methods

Through a cross-sectional study design, inhabitants of Durango City, Mexico were surveyed between June 2018 and November 2018. Serum samples from the subjects were analysed for anti-Leptospira IgG and IgM antibodies using commercially available enzyme-linked immunosorbent assays. Sociodemographic, clinical, behavioural and housing characteristics were recorded. Data were analysed by bivariate and multivariate analyses.

Results

The study enrolled 413 people, of which 124 (30.0%) and 137 (33.2%) were positive for anti-Leptospira IgG antibodies and anti-Leptospira IgM antibodies, respectively. Multivariate analysis showed that Leptospira seropositivity was associated with professional occupation, alcohol consumption, ill clinical status, memory impairment and a history of surgery.

Conclusions

This is the first study to report the seroepidemiology of Leptospira infection in an urban general population in the north of Mexico. The seroprevalence of Leptospira infection found was higher than those previously reported in Mexican studies.

Toxoplasma gondii infection in pregnant women: a cross-sectional study in Matehuala City, Mexico

OBJECTIVES

This study aimed to determine the seroprevalence of Toxoplasma gondii (T. gondii) infection in pregnant women in Matehuala City, Mexico; and the associated risk factors.

DESIGN

A cross-sectional study.

SETTING

Matehuala City, Mexico.

PARTICIPANTS

311 pregnant women.

PRIMARY AND SECONDARY OUTCOME MEASURES

Sera of women were analysed for anti-T. gondii IgG and IgM antibodies by commercially available immunoassays. Bivariate and multivariate analyses were used to assess the association between T. gondii seroprevalence and the characteristics of the pregnant women.

RESULTS

Thirteen (4.2%) of the 311 pregnant women studied were positive for anti-T. gondii IgG antibodies. No anti-T. gondii IgM antibodies were found in anti-T. gondii IgG seropositive women. No association between seropositivity and history of blood transfusion, transplantation, caesarean sections, deliveries, miscarriages or number of pregnancies was found. Logistic regression analysis of sociodemographic, behavioural and housing variables showed that availability of potable water at street represented a risk factor for T. gondii infection (age-adjusted OR=2.18; 95% CI: 1.05 to 4.53; p=0.03), whereas being born in Mexico was a protective factor for infection (age-adjusted OR=0.01; 95% CI: 0.001 to 0.35; p=0.008).

CONCLUSIONS

In this first study on the seroepidemiology of T. gondii infection in pregnant women in Matehuala, we conclude that the seroprevalence of T. gondii infection is low and similar to those reported in pregnant women in other Mexican cities. However, the seroprevalence found is lower than those reported in pregnant women in other countries in the Americas and Europe. Two risk factors associated with T. gondii infection were identified. Results of the present study may help for the optimal planning of preventive measures against toxoplasmosis in pregnant women.