HPV oral and oropharynx infection dynamics in young population.

The incidence of human papillomavirus (HPV)-associated cancers, especially those from the head and neck region, has increased. The relatively early age of presentation of HPV-positive head and neck cancer (HNC) indicates that viral infection might be acquired early in life. Persistent HPV infection has been recognized as the main risk factor for cancer development, but most studies have focused on evaluating HPV persistence in the genital region. Thus, in this work, we aimed to evaluate the prevalence of HPV in oral cavity and oropharynx in a young population, as well as the possible persistence of the infection after 12 months. Our results indicate that almost half (46.8%) of the analyzed population harbors an HPV infection either in the oral cavity or in the oropharynx. Furthermore, after 1 year of initial identification, half of them eliminated the infection, and only one person (5.26%) exhibited persistence. Interestingly, 50% of the individuals who successfully eliminated the infection acquired a new viral type, indicating that even when the primary infection is effectively eliminated by the immune system, there is a dynamic circulation of HR-HPV types that produce reinfection. This dynamic HPV infection among young individuals could influence the future establishment of cancer in some proportion of the cases.

Presence of Papillomavirus DNA sequences in the canine transmissible venereal tumor (CTVT).

BACKGROUND: The canine transmissible venereal tumor (CTVT) or Sticker's sarcoma is a neoplastic disease affecting dogs. This disease is presented as a tumoral mass in the genital organs of both, male and female individuals. Up to date, there is no clear evidence indicating a viral agent as the causative mediator for CTVT development. PURPOSE: The present work aims to analyze 21 samples from canines with CTVT for molecular identification of Papillomavirus DNA sequences. In addition, microbiological analysis, cytologic and histopathologic evaluations were also performed. RESULTS: All patients showed no biochemical and microbiological alterations. Molecular analysis demonstrated the viral DNA presence in the samples using different primer sets. The MY primers amplified a 450 bp band in seven out of 21 samples (33%). The PVF and Fap64 primer set, targeting the L1 sequence of Canine Papillomavirus (CPV), showed positivity in 16 out of 21 samples (76%). CONCLUSION: These results support the possible causative association between CPV and CTVT; nevertheless, additional studies are required to uphold such statement. This work presents evidence indicating that a viral agent might be involved in the pathogenesis of CTVT and set the bases for a better understanding of the CTVT pathobiology.

Lactate in the Regulation of Tumor Microenvironment and Therapeutic Approaches.

Tumor cells must generate sufficient ATP and biosynthetic precursors in order to maintain cell proliferation requirements. Otto Warburg showed that tumor cells uptake high amounts of glucose producing large volumes of lactate even in the presence of oxygen, this process is known as "Warburg effect or aerobic glycolysis." As a consequence of such amounts of lactate there is an acidification of the extracellular pH in tumor microenvironment, ranging between 6.0 and 6.5. This acidosis favors processes such as metastasis, angiogenesis and more importantly, immunosuppression, which has been associated to a worse clinical prognosis. Thus, lactate should be thought as an important oncometabolite in the metabolic reprogramming of cancer. In this review, we summarized the role of lactate in regulating metabolic microenvironment of cancer and discuss its relevance in the up-regulation of the enzymes lactate dehydrogenase (LDH) and monocarboxilate transporters (MCTs) in tumors. The goal of this review is to expose that lactate is not only a secondary product of cellular metabolic waste of tumor cells, but also a key molecule involved in carcinogenesis as well as in tumor immune evasion. Finally, the possible targeting of lactate production in cancer treatment is discussed.