Effect of pinealectomy and melatonin supplementation on metallothionein, ZnT2, ZIP2, ZIP4 and zinc levels in rat small intestine

The role of SLC39A4 in the prognosis, immune microenvironment, and contribution to malignant behavior in vivo and in vitro of cervical cancer

BACKGROUND

Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) are becoming more common in younger women. Solute carrier family 39 member 4 (SLC39A4) produces a zinc ion transporter involved in metastasis and invasion of tumors.

METHODS

The Cancer Genome Atlas RNA-seq data was used to investigate the expression of SLC39A4 and its prognostic potential. The assessment of the effect of SLC39A4 on cell growth and migration in CESC was conducted using MTT, colony formation, and Transwell assays. SLC39A4 was studied in vivo using a xenograft mouse model, and its functional involvement in oncogenesis was investigated by identifying the associated differentially expressed genes (DEGs). We evaluated the relationships among SLC39A4 levels, chemosensitivity, radiosensitivity and immune infiltration.

RESULTS

SLC39A4 was upregulated in CESC samples, and individuals with greater SLC39A4 mRNA expression had shorter overall survival. SLC39A4 has been identified to be a regulator of tumor cell metastasis and proliferation in vivo and in vitro, with an area under the curve of 0.874 for diagnosing CESC. In total, 948 DEGs were discovered to be enriched in key CESC progression-related signaling pathways. Additionally, intratumoral immune checkpoint and infiltration activity were associated with SLC39A4 expression. High SLC39A4 expression exhibited poor chemosensitivity and radiosensitivity profiles.

CONCLUSION

In conclusion, SLC39A4 is a key regulator of CESC development, prognosis, and the composition of the tumor immune microenvironment. SLC39A4 could be used as a prognostic or diagnostic screening tool and as a potential target for CESC treatment.

Metal ion homeostasis with emphasis on zinc and copper: Potential crucial link to explain the non-classical antioxidative properties of vitamin D and melatonin

Metal ion homeostasis is an essential physiological mechanism necessary for achieving an adequate balance of these ions' concentrations in the different cellular compartments. This fact is of great importance because both an excess and a deficiency of cellular metal ion levels are usually equally harmful due to the exacerbated increase in oxidative stress that may occur in both cases. Metal ion homeostasis ensures an equilibrium among multiple functions associated with the body's antioxidative defense network controlled by metallic micronutrients such as zinc and copper, some of the central regulators of redox processes. These micronutrients significantly modulate the activity of some isoforms of superoxide dismutase (SOD) and other enzymes such as metallothioneins (MTs) and ceruloplasmin (CP), which are directly or indirectly involved in the regulation of redox homeostasis. Although it is well known that both melatonin (MEL) and vitamin D have important roles as natural antioxidants, often some of these effects are related to their actions on antioxidative processes dependent on metal ions. Thus, in addition to their classical antioxidative properties usually associated with mitochondrial effects, it is known that MEL and vitamin D modulate the expression and activity of Cu/Zn-dependent SOD isoforms, MTs and CP; function as copper chelators and regulate genomic and non-genomic mechanisms related to the zinc transport. This review summarizes the main findings related to the crucial participation of zinc and copper in physiological antioxidative status and their relationship with the non-classical antioxidant effects of MEL and vitamin D, suggesting a potential synergism among these four micronutrients.