Here, using human and canine melanoma cells, we elucidated the effects of miR-203 on cyclic adenosine monophosphate response element binding protein (CREB)/microphthalmia-associated transcription factor (MITF)/RAB27a pathway, which is known to be important for the development and progression of human melanoma.
In addition, this study suggests that agents that can demethylate MIR203 could be a common promising therapeutic agent for the treatment of human and canine melanomas.
In conclusion, our data indicated that anti-oncogenic miR-203 had a pivotal role in melanoma through reducing melanosome transport and promoting melanogenesis by targeting kif5b and through negative regulation of the CREB1/MITF/Rab27a pathway.
In the present study, after observation of upregulation of miR-203 in melanoma patient's serum and also melanospheres as cancer stem cells model, we examined its overexpression on the stemness potential and migration ability of melanoma cells.
Multivariate analysis indicated that miR-203 could be an independent prognostic marker (P=0.003, HR=2.851, 95% CI=1.439-5.650) in melanoma This study for the first time provided evidence that miR-203 could be an independent potential prognostic marker for patients with melanoma, and might even become a new therapeutic target for the treatment of melanoma.
Our data suggest that miR-203 is a new prognostic factor in canine oral MMs and that miR-205 functions as a tumour suppressor by targeting erbb3 in both canine and human MM cells.
Significantly lower miR-145-5p and miR-203-3p expression levels were found in cases with Breslow thickness >1 mm, high Clark level, ulceration and mitotic rate ≥1/mm<sup>2</sup> Conclusion: Our findings point to miR-205-5p as potential biomarker of distant metastases and to miR-145-5p and miR-203-3p as markers of aggressiveness in melanoma.
Taken together, our results demonstrated that miR-203 regulated melanoma invasive and proliferative abilities in part by targeting BMI1, providing new insights into potential mechanisms of melanoma metastasis.