Vascular endothelial growth factor response with propranolol therapy in patients with infantile hemangioma

Efficacy and safety of oral propranolol and topical timolol in the treatment of infantile hemangioma: a meta-analysis and systematic review

BACKGROUND

Propranolol, a nonselective β-blocker, is the first-line treatment for infantile hemangioma (IH). Topical timolol has recently been proposed as a novel IH treatment with fewer adverse effects. This study was conducted to compare the efficacy and safety of oral propranolol and topical timolol for treating IH.

METHODS

Studies were included after searching PubMed, Embase, Web of Science, and the Cochrane Library via the keywords of "propranolol", "timolol", "infantile hemangioma" and their synonyms. A meta-analysis with pooled odds ratios was performed using the fixed-effect model.

RESULTS

Seven articles with 2071 patients were included in this meta-analysis. Compared with topical timolol, oral propranolol had a greater response rate (OR = 2.12, P < 0.001), but it was also associated with a greater risk of adverse events (OR = 2.31, P < 0.001). For superficial IH, timolol demonstrated similar efficacy to propranolol (OR = 1.28, P = 0.34) but with fewer adverse events (OR = 2.30, P = 0.001). Additionally, compared with topical timolol, propranolol at a dosage of 2 mg/kg/d had a better response rate (OR = 2.62, P < 0.001), whereas the 1.0∼1.5 mg/kg/d propranolol group showed no significant difference (OR = 1.34, P = 0.38).

CONCLUSION

Oral propranolol presents superior therapeutic efficacy in the treatment of IH compared to topical timolol. However, topical timolol can serve as an alternative to oral propranolol for treating superficial IH, providing similar efficacy with fewer adverse effects. Additionally, propranolol at a dosage of 2 mg/kg/d offers greater efficacy with a comparable safety profile, whereas the 1.0∼1.5 mg/kg/d propranolol dosage shows no significant difference in efficacy compared to timolol but is associated with more adverse events.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024603724, identifier CRD42024603724.

Timing and Efficacy Evaluation of 755-nm Long Pulse Alexandrite Laser and 2% Carteolol Hydrochloride Eye Drops Co-Treatment for Thicker Superficial Infantile Hemangioma

Purpose

Superficial Infantile hemangioma (SIH) is the most common type of IH. Some studies have shown the efficacy of 755-nm long pulse alexandrite laser (LPAL) and topical 2% carteolol hydrochloride (C-HCL) eye drops for the treatment of SIH. This article retrospectively analyzes the safety and efficacy of 755-nm LPAL combined with 2% C-HCL eye drops for treating thicker SIH, and explores the optimal treatment time for SIH.

Materials and Methods

This study included 2-5 mm thick SIH patients who received co-treatment of 755-nm LPAL and 2% C-HCL eye drops. The SIH patients were divided into 3 groups based on their age and IH growth curve: ≤ 1 month (≤ 1M), 1-3 months (excluding 1 month; 1-3M), and 3-12 months (excluding 3 months; 3-12M).

Results

There was no difference in efficacy between the ≤ 1M and the 1-3M group, and were both better than the 3-12M group. Furthermore, there was no difference in the average number of treatments between the ≤ 1M and 1-3M groups and were both less than the 3-12M group. There was no significant difference in the incidence of adverse reactions between the groups. Compared with the ≤ 1M and 1-3M groups, the 3-12M group indicated more permanent skin lesions after the treatment.

Conclusion

It was revealed that co-treatment with 755-nm LPAL and 2% C-HCL eye drops is safe and effective against thicker SIH. Compared with the 3-12M group, ≤ 3 months can achieve better efficacy, requires a shorter treatment time, less likely to leave permanent skin lesions such as scars. Moreover, patients with no proliferation can be observed to 1 month.

Insights into the mechanisms of angiogenesis in infantile hemangioma

Infantile hemangioma (IH) is the most common benign tumor in infants and usually resolves on its own. However, a small portion of IH cases are accompanied by serious complications and other problems, impacting the physical and psychological health of the children affected. The pathogenesis of IH is highly controversial. Studies have shown that abnormal blood vessel formation is an important pathological basis for the development of IH. Compared with that in normal tissues, the equilibrium of blood vessel growth at the tumor site is disrupted, and interactions among other types of cells, such as immune cells, promote the rapid proliferation and migration of vascular tissue cells and the construction of vascular networks. Currently, propranolol is the most common systemic drug used to inhibit the growth of IHs and accelerate their regression. The purpose of this review is to provide the latest research on the mechanisms of angiogenesis in IH. We discuss the possible roles of three major factors, namely, estrogen, hypoxia, and inflammation, in the development of IH. Additionally, we summarize the key roles of tumor cell subpopulations, such as pericytes, in the proliferation and regression of IH considering evidence from the past few years, with an emphasis on the possible mechanisms of propranolol in the treatment of IH. Angiogenesis is an important event during the development of IH, and an in-depth understanding of the molecular mechanisms of angiogenesis will provide new insights into the biology and clinical treatment of IH.

Circulating Mesenchymal Stromal Cells in Patients with Infantile Hemangioma: Evaluation of Their Functional Capacity and Gene Expression Profile

We previously published that in patients with infantile hemangioma (IH) at the onset (T0) colony forming unit-fibroblasts (CFU-Fs) are present in in vitro cultures from PB. Herein, we characterize these CFU-Fs and investigate their potential role in IH pathogenesis, before and after propranolol therapy. The CFU-F phenotype (by flow cytometry), their differentiation capacity and ability to support angiogenesis (by in vitro cultures) and their gene expression (by RT-PCR) were evaluated. We found that CFU-Fs are actual circulating MSCs (cMSCs). In patients at T0, cMSCs had reduced adipogenic potential, supported the formation of tube-like structures in vitro and showed either inflammatory (IL1β and ESM1) or angiogenic (F3) gene expression higher than that of cMSCs from CTRLs. In patients receiving one-year propranolol therapy, the cMSC differentiation in adipocytes improved, while their support in in vitro tube-like formation was lost; no difference was found between patient and CTRL cMSC gene expressions. In conclusion, in patients with IH at T0 the cMSC reduced adipogenic potential, their support in angiogenic activity and the inflammatory/angiogenic gene expression may fuel the tumor growth. One-year propranolol therapy modifies this picture, suggesting cMSCs as one of the drug targets.

Importance of Determining Vascular Endothelial Growth Factor Serum Levels in Children with Infantile Hemangioma

Background and Objectives: A potential role of vascular endothelial growth factor (VEGF) in the pathophysiology of infantile hemangiomas (IH) is thought to be plausible. The primary objective of this study was to investigate the importance of determining VEGF serum levels at various stages of IH growth in children. Materials and Methods: A nested case-control study was conducted. For the purposes of the researched target group, samples of fifty (N = 50) children with IH without associated diseases at different stages of hemangioma growth (proliferative and involutional stages) were used. The control group consisted of one hundred (N = 100) healthy children comparable in terms of age and sex, in whom the existence of IH and vascular malformations was ruled out via clinical examination. An immunoassay (ELISA) was used to determine VEGF serum levels in hemangioma growth's proliferation and involution phases. Results: A comparison of serum levels of VEGF in the phases of proliferation and involution in the group of patients with IH did not show a statistically significant difference (p = 0.171). The control group had significantly higher serum VEGF levels than the patient group in both the proliferation phase (p = 0.009) and the involution phase (p = 0.019). In the proliferation phase, a multivariate regression model explained 15% of the variance in the dependent variable, without significant predictor variables, while in the involution phase, it explained 21% of the variance in the dependent variable, and the history of invasive prenatal procedures stood out as a significant predictor variable positively associated with serum VEGF levels (beta coefficient = 0.33; p = 0.043). Conclusions: Although IH is thought to be the result of the dysregulation of angiogenesis and vasculogenesis under the influence of angiogenic factors, especially VEGF, this study did not demonstrate that VEGF serum levels in the proliferation phase of hemangioma growth were higher than those in the involution phase, or in relation to the control group.

Management of infantile hemangiomas: Recent advances

Infantile hemangiomas (IHs) are benign vascular tumors commonly observed in children. A small number of cases can manifest as organ or system dysfunction, permanent scarring, or even disfigurement. Currently, diagnosis is mainly based on clinical history, physical examination, and auxiliary inspection. In the treatment of a hemangioma, the functional damage caused by the lesion and complications that may endanger the patient’s life should be given priority. This suggests that identification, diagnosis, and referral to specialists during the early stages of IHs are important factors in preventing related complications and obtaining a better prognosis. During the past few decades, researchers have explored different treatments according to the condition, including oral or topical drugs, topical drug injections, laser surgery, and surgical treatment. However, oral propranolol remains a well-accepted first-line treatment. This article will primarily focus on the recent advances in the clinical diagnosis and treatment of hemangiomas, along with a literature review on the subject.

Low-dose sclerotherapy with lauromacrogol in the treatment of infantile hemangiomas: A retrospective analysis of 368 cases

BACKGROUND

Intralesional injection of lauromacrogol has proven to be an efficient treatment method for infantile hemangioma. This study aims to explore a novel injection therapy and evaluate its efficacy and complications.

METHODS

The medical records of 368 children with infantile hemangioma who received a lauromacrogol injection from January 2021 to April 2022 were retrospectively analyzed. All patients were reviewed every 4 weeks, and their condition was assessed according to symptoms and medical records. The patient's age, lesion type, location, size and thickness, lesion photographs, ultrasound, and complications were recorded.

RESULTS

Among the 368 infants who accept sclerotherapy with lauromacrogol, 226(61.4%)achieved excellent regression. In total, 108(29.4%)cases achieved good regression. 24(6.5%)achieved complete moderate regression. 10(2.7%)achieved poor regression. The reported incidence of adverse events was 4.9% and severe complications were not observed. Before and after three courses of treatment, the median vascular endothelial growth factor levels were 104.12 pg/ml and 28.982 pg/ml. There was a significant difference between the two groups (P=0.0043).

CONCLUSIONS

The results showed that this novel injection therapy a safe and effective treatment method. The therapy accelerated the regression of infantile hemangiomas without serious complications.

Β-blockers activate autophagy on infantile hemangioma-derived endothelial cells in vitro

The mechanisms underlying the success of propranolol in the treatment of infantile hemangioma (IH) remain elusive and do not fully explain the rapid regression of hemangiomatous lesions following drug administration. As autophagy is critically implicated in vascular homeostasis, we determined whether β-blockers trigger the autophagic flux on infantile hemangioma-derived endothelial cells (Hem-ECs) in vitro.

MATERIAL AND METHODS

Fresh tissue specimens, surgically removed for therapeutic purpose to seven children affected by proliferative IH, were subjected to enzymatic digestion. Cells were sorted with anti-human CD31 immunolabeled magnetic microbeads. Following phenotypic characterization, expanded Hem-ECs, at P2 to P6, were exposed to different concentrations (50 μM to 150 μM) of propranolol, atenolol or metoprolol alone and in combination with the autophagy inhibitor Bafilomycin A1. Rapamycin, a potent inducer of autophagy, was also used as control. Autophagy was assessed by Lysotracker Red staining, western blot analysis of LC3BII/LC3BI and p62, and morphologically by transmission electron microscopy.

RESULTS

Hem-ECs treated with either propranolol, atenolol or metoprolol displayed positive LysoTracker Red staining. Increased LC3BII/LC3BI ratio, as well as p62 modulation, were documented in β-blockers treated Hem-ECs. Abundant autophagic vacuoles and multilamellar bodies characterized the cytoplasmic ultrastructural features of autophagy in cultured Hem-ECs exposed in vitro to β-blocking agents. Importantly, similar biochemical and morphologic evidence of autophagy were observed following rapamycin while Bafilomycin A1 significantly prevented the autophagic flux promoted by β-blockers in Hem-ECs.

CONCLUSION

Our data suggest that autophagy may be ascribed among the mechanisms of action of β-blockers suggesting new mechanistic insights on the potential therapeutic application of this class of drugs in pathologic conditions involving uncontrolled angiogenesis.