A multicenter consensus: A role of furin in the endothelial tropism in obese patients with COVID-19 infection

Furin, a cleavage enzyme, is increasingly recognized in the pathogenesis of metabolic syndrome. Its cleavage action is an essential activation step for the endothelial pathogenicity of several viruses including SARS-CoV-2. This Furin-mediated endothelial tropism seems to underlie the multi-organ system involvement of COVID-19; which is a feature that was not recognized in the older versions of coronaviridae. Obese and diabetic patients, males, and the elderly, have increased serum levels of Furin, with its increased cellular activity; this might explain why these subgroups are at an increased risk of COVID-19 related complications and deaths. In contrast, smoking decreases cellular levels of Furin, this finding may be at the origin of the decreased severity of COVID-19 in smokers. Chinese herbal derived luteolin is suggested to be putative Furin inhibitor, with previous success against Dengue Fever. Additionally, Furin intracellular levels are largely dependent on concentration of intracellular ions, notably sodium, potassium, and magnesium. Consequently, the use of ion channel inhibitors, such as Calcium Channel blockers or Potassium Channel blockers, can prevent cellular transfection early in the course of the illness. Nicotine patches and Colchicine have also been suggested as potential therapies due to Furin mediated inhibition of COVID-19.

[Tissue collagenase MMP-14 and endogenous regulators of its activity in the corpus uteri in squamous cell carcinoma of the cervix]

AIM

to investigate the expression of the membrane-bound matrix metalloproteinase MT1-MMP (MMP-14), its tissue inhibitor TIMP-2, and the proMMP-14 activator furin in the corpus uteri from the vaginal wall to the bottom of the uterine cavity in squamous cell carcinoma of the cervix (SCCC).

MATERIAL AND METHODS

Hysterectomy material was examined in patients with SCCC. Reverse transcriptase polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and enzyme assays were used.

RESULTS

In SCCC, higher levels of MMP-14 expression were established in tumor cells, as evidenced by IHC (+3) and RT-PCR. IHC showed that the expression of MMP-14 was absent or insignificant in the normal uterine endometrial and myometrial tissues. However, that of MMP-14 mRNA was also found in the normal tissues to the bottom of the uterine cavity. Furin activity in the tumor was much higher than that in normal tissues. IHC indicated that TIMP-2 expression was low or absent in both the tumor and normal tissues. The expression of TIMP-2 mRNA was sufficiently obvious in both the tumor and normal tissues to the bottom of the uterine cavity.

CONCLUSION

In SCCC, MMP-14 expression was substantially increased in tumors. The expression of MMP-14 and regulators of its activity is aimed at enhancing the tumor destructive (invasive) potential in the pericellular space and can occur (be induced) in the morphologically normal uterine tissue apparently with involvement of signaling through the epithelial-mesenchymal interaction. Data are important for understanding the role of MMP-14 in the development of a multistage process of carcinogenesis and may have prognostic value and an impact on therapeutic strategy for the patient.