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Polylactosamine (polyLacNAc) is a fundamental structure in glycoconjugates and it is expressed in specific cells/tissues associated with the development and carcinogenesis. β1,3-N-acetylglucosaminyl transferases (β3GnTs) play an important role in polyLacNAc synthesis, however the roles of these glycosyltransferases and their products in cancer progression are still unclear. In this sense, this work aimed to evaluate differential expression pattern of the N-acetylglucosaminyl transferases and polylactosamines in invasive and premalignant lesions of the uterus cervix. The expression of β3GnT2 and β3GnT3 were evaluated in normal (n=10) and uterine cervix lesions (n= 120) malignant (squamous carcinoma - SC) and premalignant (cervical intraepithelial neoplasia - CIN - grades 1, 2 and 3) using immunohistochemistry. Besides, lectin histochemistry with Phytolacca americana lectin (PWM) and Wheat germ agglutinin (WGA) was also carried out to observe the presence of polyLacNAc chains and N-acetylglucosamine (GlcNAc), respectively. The β3GnT3 was expressed in almost all samples (99%) and β3GnT2 was higher expressed in disease samples mainly in CIN 3, when compared with normal (P=0.002), CIN 1 (P=0.009) and CIN 2 (P=0.03). The expression of polyLacNAc was higher is SC samples, when compared with normal (P=0.03), CIN 1 (P=0.02) and CIN 3 (P=0.004), and was observed only nuclear expression in nearly 50% of the SC samples, showing a statistically significant when compared with normal (P=0.01), CIN 1 (P=0.002), CIN 2 (P=0.007) and CIN 3 (P=0.04). Deferring from transferases and polyLacNAc chains, GlcNAc (WGA ligand) reveals a gradual staining pattern decrease with the increase of the lesion degree, being more expressed in CIN 1 lesions when compared with normal (P<0.0001), CIN 2 (P<0.0001), SC (P<0.0001) and CIN 3 (P=0.0003). Our data reveals β3GnT2 and polyLacNAc may be involved in the progression of the pre-malignant lesions of human the uterine cervix. In addition, polyLacNAc expression only in the nucleus can be associated a poor prognostic in uterine lesions.

Altered sialylation has been observed during oncogenic transformation and has been implicated in tumor progression and metastases. This pattern may aid the biological behavior of many tumors. Skin cancer is the most common cancer worldwide and their diagnosis becomes difficult, in some cases, due to variety of factors that affect the accuracy of the nowadays exams, such as huge spectrum of tumors and their variants. So, this study investigates the changes in expression and distribution of α2,3 and α2,6-linked sialic acid in non-melanomas skin cancer to identify the sialylation pattern which may be useful in the differential diagnosis of this tumor. Lectin histochemistry was used to examine the expression and distribution of sialic acid in different types of non-melanoma skin cancers. We applied Maackia amurensis lectin, which interacts with α2,3-linked sialic acid and Sambucus nigra lectin specific for α2,6-linked sialic acid. The histochemical analysis showed that α2,3 and α2,6-linked sialic acid vary their expression according with the tumor type analyzed. The distribution of α2,3-linked sialic was differentially expressed in between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) (p < 0.0001), BCC and actinic keratosis (p = 0.0033) and BCC and keratoacanthoma (p < 0.0001). In the case of α2,6-linked sialic acid its expression was also different between BCC and SCC (p < 0.0001), BCC and actinic keratosis (p = 0.0002) and BCC and keratoacanthoma (p < 0.0362). Lectin histochemistry showed a different expression of both sialic acid linkages types between pre-malign and malign tumors and between malign tumors. Although preliminary, these findings are promising for the development of diagnostic techniques to help in the differential diagnosis of non-melanoma skin tumors using lectin histochemistry as an auxiliary tool.