The big challenge of SARS-CoV-2 latency: testes as reservoir / El gran desafío de la latencia de SARS-CoV-2: el testículo como reservorio

Abstract In the efforts to explain COVID-19 pathophysiology, studies are being carried out on the correspondence between the expression of SARS-CoV-2 cell receptors and viral sequences. ACE2, CD147 and TMPRSS2 receptors expression could indicate poorly explored potential infection targets. For the genomic analysis of SARS-CoV-2 receptors, using BioGPS information was decided, which is a portal that centralizes genetic annotation resources, in combination with that of The Human Protein Atlas, the largest portal of human transcriptome and proteome data. We also reviewed the most recent articles on the subject. RNA and viral receptor proteins expression was observed in numerous anatomical sites, which partially coincides with the information reported in the literature. High expression in testicular cells markedly stood out, and it would be therefore important ruling out whether this anatomical site is a SARS-CoV-2 reservoir; otherwise, germ cell damage, as it is observed in infections with other RNA viruses, should be determined.

Resumen En el afán por explicar la fisiopatogenia de COVID-19 se están realizando estudios en torno a la correspondencia entre la expresión de receptores celulares de SARS-CoV-2 y las secuencias virales. La expresión de los receptores ACE2, CD147 y TMPRSS2 podría indicar blancos de infección poco explorados. Para el análisis genómico de los receptores de SARS-CoV-2 se optó por utilizar la información del BioGPS, un portal que centraliza los recursos de anotación genética, en combinación con la de The Human Protein Atlas, el portal más grande de datos del transcriptoma y proteoma humanos. También se revisaron los artículos más recientemente respecto al tema. En numerosos sitios anatómicos se observó la expresión de ARN y proteínas de los receptores del virus, que coinciden parcialmente con la información reportada en la literatura. Resaltó la alta expresión en las células de los testículos, por lo que sería importante descartar si este sitio anatómico es un reservorio de SARS-CoV-2; de no ser así, determinar el daño en las células germinales, tal como sucede en infecciones por otros virus ARN.

Up-regulated expression of CD147 gene in malignant bone tumor and the possible induction mechanism during osteoclast formation

It is increasingly evident that the microenvironment of bone can influence cancer phenotype in many ways that favor growth in bone. CD147, a transmembrane protein of the immunoglobulin (Ig) superfamily, was identified independently in different species and has many designations across different species. However, expression levels of CD147 mRNA in bone cancer have not been described. In this study, we have used real-time fluorescence quantification (RT-PCR) to demonstrate CD147 expression in malignant bone cancer and benign bone tumor tissues. The results suggested that the expression of CD147 gene was significantly up-regulated in malignant bone cancer. Moreover, we found that over-expressed RANKL progressively enhanced osteoclast formation up to 48 h, which suggested that RANKL could promote the formation of osteoclast, indicating that both CD147 and RANKL play important roles in the formation of osteoclasts. Furthermore, the expressions of four osteoclast specific expression genes, including TRACP, MMP-2, MMP-9 and c-Src, were analyzed using RT-PCR. The results indicated that four osteoclast-specific expression genes were detectable in all osteoclast with different treatments. However, the highest expression level of these four osteoclast-specific expression genes appears in the CD147+ RANKL group and the lowest expression level of these four osteoclast-specific expression genes appears with si-RANKL treatment. Characterization of the role of CD147 in the development of tumors should lead to a better understanding of the changes occurring at the molecular level during the development and progression of primary human bone cancer.