Propranolol Treatment of Vascular Anomalies Other Than Infantile Hemangioma

Systemic, local, and sclerotherapy drugs: What do we know about drug prescribing in vascular anomalies?

Off-label drug prescribing, frequent in the treatment of vascular anomalies (VA), relies on the quality of the literature reporting drug efficacy and safety. Our objective is to review the level of evidence (LOE) surrounding drug use in VA, which is more prevalent in pediatric care. A list of drugs used in VA was created with a literature review in July 2020. For each drug listed, the article displaying the highest LOE was determined and then compared between efficacy/safety data, routes of administration, pharmacological categories and a subset of VA. The influence of research quality on study results was also explored. The median LOE for the 74 drugs identified poor methodological quality, with a predominance of retrospective studies or case reports. Drug safety is currently inadequately reported. This is alarming as many treatments display significant safety concerns. Also, current literature displays major publication bias that probably leads to overestimation of drug efficacy in VA.

Expression of β1 adrenergic receptor in vascular anomalies in children

OBJECTIVE

Controversial, heterogeneous, and inconsistent responses to beta-blockers have been reported in some cases of infantile proliferative hemangiomas. On the basis of these clinical observations, we aimed to examine the β1 adrenergic receptor (β1-AR) protein expression distribution among different types of pediatric vascular anomalies.

METHODS

Immunohistochemistry (IHC) was performed for β1-AR on 43 surgical specimens.

RESULTS

We found positive β1-AR IHC staining in all intramuscular hemangiomas, capillary-lymphatic, lymphatic, venous, and combined malformations, and Masson's tumor cases, as well as in 7 of 10 cases of proliferative infantile hemangiomas.

CONCLUSIONS

Our research demonstrates, for the first time, the degree of heterogeneous expression of β1-AR among pediatric vascular malformations. Our results support the need for β1-AR assessment in pediatric vascular anomalies to select cases with a robust response to β1-selective blockers. β1-AR assessment may have a strong impact on therapeutic refinement for pediatric vascular anomalies by selecting cases with a stronger response to beta-blockers.

MiR-206 promotes extracellular matrix accumulation and relieves infantile hemangioma through targeted inhibition of DNMT3A

MiR-206 is abnormally expressed in infant hemangioma endothelial cells (HemECs), but the mechanism is not clear. We explored the intervention of miR-206 in HemECs in relation to extracellular matrix (ECM) metabolism. We selected 48 cases of infantile hemangioma (IH) from volunteer organizations. After the isolated and extracted HemECs were interfered with overexpressed or silenced miR-206, the effects of miR-206 on the proliferation, migration and invasion of HemECs were examined through basic cell function experiments. The expression differences of miR-206, DNA Methyltransferase 3A (DNMT3A) and ECM-related genes were analyzed as needed by qRT-PCR or Western blot. TargetScan and dual-luciferase experiments were applied to predict and confirm the binding relationship between miR-206 and DNMT3A. The correlation between miR-206 and DNMT3A was analyzed in IH tissues by Pearson correlation coefficient, and further confirmed in HemECs by conducting rescue experiments. A nude mouse model of xenograft tumor was constructed to verify the results of in vitro experiments. MiR-206, which was downregulated in proliferative hemangioma, suppressed the malignant development of HemECs by regulating ECM-related genes. As the target gene of miR-206, DNMT3A was high-expressed in IH tissues and was negatively correlated with miR-206. Overexpressed DNMT3A counteracted the inhibitory effect of miR-206 mimic on HemECs and its regulatory effect on ECM. The results of in vivo experiments were consistent with those from cell experiments. Thus, miR-206 could promote ECM accumulation through targeted inhibition of DNMT3A, further inhibiting the malignant development of HemECs and relieving IH.

Oral Propranolol in the Treatment of Ulcerated Bleeding Scrotal Arteriovenous Malformation

Arteriovenous malformations (AVMs) of the scrotum are very rare, with only 35 adult cases in the literature. An 8-year-old boy presented with an ulcerated bleeding AVM of the scrotum. The patient was resuscitated and managed conservatively initially. After the control of bleeding, oral propranolol was started. There was a decrease in the size of scrotal and penile swelling, healing of ulcer with total healing by 1 month, and no recurrence of bleeding episode. To the best of our knowledge, this was the first case of pediatric scrotal AVM treated by oral propranolol.

Application of the adenosine triphosphate sensitivity assay in infantile vascular anomalies

Background

The term vascular anomalies include various vascular tumors and vascular malformations, among them infantile hemangiomas and capillary malformations are the most well-known associated diseases in early ages. Multiple drugs have been introduced for intervention, but susceptibility test in vitro were scarcely reported.

Objective

To evaluate the inhibition effect of different drugs by adenosine triphosphate sensitivity assay in vitro before the treatment of infantile hemangiomas and capillary malformations.

Methods

Specimens were selected from 5 cases of infantile hemangiomas and 11 cases of capillary malformations. Propranolol, rapamycin, sildenafil and itraconazole were tested for their growth inhibition effect by using the adenosine triphosphate sensitivity assay.

Results

Propranolol demonstrated inhibitory effects on infantile hemangiomas cells. Rapamycin and itraconazole both showed inhibitory effects on infantile hemangiomas cells and capillary malformations cells. Sildenafil has no growth inhibitory effect on infantile hemangiomas cells or capillary malformations cells.

Conclusion

Adenosine triphosphate sensitivity assay is a sensitive and useful testing method before the management of vascular anomalies, and individualized medication suggestions for the choice of therapeutic drugs were offered based on the testing result and together with a comprehensive evaluation of each infant.