Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA)-related overgrowth spectrum: A brief report

3D in vitro modelling of post-partum cardiovascular health reveals unique characteristics and signatures following hypertensive disorders in pregnancy

BACKGROUND

Hypertensive disorders of pregnancy (HDP) affect 2-8% of pregnancies and are associated postpartum with increased cardiovascular disease (CVD) risk, although mechanisms are poorly understood.

METHODS

Human induced pluripotent stem cells (iPSC)-derived cardiomyocytes, cardiac fibroblasts and coronary artery endothelial cells were cocultured to form cardiac spheroids (CSs) in collagen type-1 hydrogels containing 10% patient plasma collected five years postpartum [n = 5 per group: normotensive control, gestational hypertension (GH) and preeclampsia (PE)]. Plasma-treated CSs were assessed for cell viability and contractile function and subjected to immunofluorescence staining and imaging. A quantitative proteomic analysis of plasma samples was conducted (controls n = 21; GH n = 5; PE n = 12).

RESULTS

Contraction frequency (CF) was increased in PE-treated CSs (CF: 45.5 ± 3.4 contractions/minute, p < 0.001) and GH-treated CSs (CF: 45.7 ± 4.0 contractions/minute, p < 0.001), compared to controls (CF = 21.8 ± 2.6 contractions/min). Only PE-treated CSs presented significantly increased fractional shortening (FS) % (9.95 ± 1.8%, p < 0.05) compared to controls (3.7 ± 1.1%). GH-treated CSs showed a reduction in cell viability (p < 0.05) and an increase in α-SMA expression (p < 0.05). Proteomics analyses identified twenty differentially abundant proteins, with hemoglobin A2 being the only protein perturbed in both GH and PE versus control plasma (p < 0.05).

CONCLUSIONS

The innovative patient-relevant CS platforms led to the discovery of biomarkers/targets linked to cell death signaling and cardiac remodeling in GH-induced CVD and vascular/endothelial cell dysfunction in PE-induced CVD.

Recurrent hematuria involving urinary system with Klippel-Trenaunay syndrome: A case report

RATIONALE

Klippel-Trenaunay syndrome (KTS) is a rare congenital venous malformation, it had been found to be caused by mutations of the phosphatidylinositol 4, 5-diphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene. Currently KTS is defined as a triad of skin wine pigmented spots, varicose veins and malformations of the lower extremities, and hypertrophy of bone and soft tissue, involving urinary system up to 6% to 30%. When the urinary system is involved, KTS is often presented as painless massive gross hematuria.

PATIENT CONCERNS

This article describes a woman who was hospitalized with painless massive gross hematuria. Physical examination revealed significant hypertrophy of the right lower limb with varicose veins, port-wine stains in the skin, and right perineal hemangiomatous changes with swelling. The patient was admitted to hospital 4 times for repeated hematuria and infection.

DIAGNOSES

By physical examination, CT urography, ureteroscopy and cystoscopy, the patient was diagnosed to have Klippel-Trenaunay syndrome, involving the urinary system.

INTERVENTIONS

The patient hematuria improved after multiple indwelling D-J tubes and anti-inflammatory treatment.

OUTCOMES

The final symptoms of hematuria improved significantly, follow-up so far has not recurred.

LESSONS

This case presents the possibility of painless gross hematuria with KTS. Most of patients can be improved by conservative treatment. Cystoscopic laser therapy is the preferred treatment for poor bleeding control. Cystectomy and nephrectomy should be considered when life-threatening.

Case Report: Sequential postzygotic HRAS mutation and gains of the paternal chromosome 11 carrying the mutated allele in a patient with epidermal nevus and rhabdomyosarcoma: evidence of a multiple-hit mechanism involving HRAS in oncogenic transformation

We report a 7-year-old boy born with epidermal nevi (EN) arranged according to Blaschko's lines involving the face and head, right upper limb, chest, and left lower limb, who developed a left paratesticular embryonal rhabdomyosarcoma at 18 months of age. Parallel sequencing identified a gain-of-function variant (c.37G>C, p.Gly13Arg) of HRAS in both epidermal nevus and tumor but not in leukocytes or buccal mucosal epithelial cells, indicating its postzygotic origin. The variant accounted for 33% and 92% of the total reads in the nevus and tumor DNA specimens, respectively, supporting additional somatic hits in the latter. DNA methylation (DNAm) profiling of the tumor documented a signature consistent with embryonal rhabdomyosarcoma and CNV array analysis inferred from the DNAm arrays and subsequent MLPA analysis demonstrated copy number gains of the entire paternal chromosome 11 carrying the mutated HRAS allele, likely as the result of paternal unidisomy followed by subsequent gain(s) of the paternal chromosome in the tumor. Other structural rearrangements were observed in the tumours, while no additional pathogenic variants affecting genes with role in the RAS-MAPK and PI3K-AKT-MTOR pathways were identified. Our findings provide further evidence of the contribution of "gene dosage" to the multistep process driving cell transformation associated with hyperactive HRAS function.

Cerebral cavernous malformations do not fall in the spectrum of PIK3CA-related overgrowth

Somatic gain-of-function (GOF) mutations in phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), the catalytic subunit of phosphoinositide 3-kinase (PI3K), have been recently discovered in cerebral cavernous malformations (CCMs), raising the possibility that the activation of PI3K pathways is a possible universal regulator of vascular morphogenesis. However, there have been contradicting data presented among various groups and studies. To enhance the current understanding of vascular anomalies, it is essential to explore this possible relationship between altered PI3K signalling pathways and its influence on the pathogenesis of CCMs. GOF PIK3CA-mutants have been linked to overgrowth syndromes, allowing this group of disorders, resulting from somatic activating mutations in PIK3CA, to be collectively named as PIK3CA-related overgrowth spectrum disorders. This paper reviews and attempts to conceptualise the relationships and differences among clinical presentations, genotypic and phenotypic correlations and possible coexistence of PIK3CA and CCM mutations/phenotypes in CCM lesions. Finally, we present a model reflecting our hypothetical understanding of CCM pathogenesis based on a systematic review and conceptualisation of data obtained from other studies.

CLOVES Syndrome Diagnosis and Treatment in an Adult Patient

CLOVES syndrome is a rare, nonheritable sporadic overgrowth disorder. In the world 130-200 cases have been reported. This is the first case of CLOVES described in Portugal, which had been not been diagnosed for the last 36 years. With this paper, the authors look to highlight the clinical features of this syndrome so that it does not go unrecognized in daily practice. The authors also underline the efficacy and safety of sirolimus, and that this treatment should not be denied, even in adult patients.

A narrative review of the role of sirolimus in the treatment of congenital vascular malformations

OBJECTIVE

Vascular malformations arise from defects in the morphologic development of the vascular system and can have an impact on quality of life and/or lead to severe complications. To date, vascular malformations are frequently managed by invasive techniques, after which recurrence is common. Sirolimus, a downstream inhibitor of the phosphatidylinositol 3 kinase/AKT pathway and best known for its immunosuppressive effect, has been used off-label for lesions for which approved therapies were associated with unsatisfactory results or recurrence. The aim of this study was to review the available data on the effect of sirolimus on the size and symptoms of different types of malformations and to summarize the main safety issues.

METHODS

A literature search in Pubmed, Embase, Web of Science, and SCOPUS was performed. Case reports, case series, and clinical trials evaluating the effect of sirolimus in vascular malformations were eligible for this review. Fully terminated studies published between January 2010 and May 2019 reporting an evaluable response on size and/or symptoms were included. Relevant data on lesion size, symptoms, side effects and duration of treatment were extracted as reported in the study. Additionally, we reported 10 unpublished cases who were treated in UZ Leuven.

RESULTS

The literature review included 68 articles, describing 324 patients. The median duration of therapy was 12 months (range, 1-60 months). After 6 months of treatment, the size of the malformation had at least decreased in 67% of patients with common venous malformations (VM), in 93% of patients with blue rubber bleb nevus syndrome and in all patients with verrucous VM. The size of lymphatic malformations improved in more than 80% of the patients, even in the case of extensive involvement such as in Gorham-Stout disease and generalized lymphatic anomaly. In addition, the majority of patients with syndromic vascular malformations experienced a decrease in size and reported symptoms improved in almost all patients, regardless of the type of malformation. Side effects were common (53%) but usually mild; mucositis and bone marrow suppression were the most common. Regrowth or recurrence of symptoms occurred in 49% of patients who discontinued treatment. Comparable effects were seen in our own patients.

CONCLUSIONS

This review shows that sirolimus is effective in decreasing the size and/or symptoms of particularly lymphatic malformations as well as VMs. Although common, side effects were usually mild. Nevertheless, clinical trials are needed to confirm the safety and effectivity of sirolimus and to identify the required serum levels and duration of treatment.

Genitourinary involvement in pediatric patients with Klippel-Trenaunay Syndrome

BACKGROUND

Klippel-Trenaunay Syndrome (KTS) is a genetic vascular malformation disorder which induces a variety of phenotypic expression in patients which differ in terms of severity/location. While previous studies have documented genitourinary (GU) complications in adult KTS patients, documentation of the scope and incidence of GU involvement in the pediatric population with imaging findings is currently limited. This study represents the largest KTS genitourinary review to date.

OBJECTIVE

To assess the incidence, scope, clinical findings and imaging characteristics of GU pathology in pediatric KTS patients.

MATERIALS/METHODS

Using a retrospective data analysis design, the charts and imaging studies of pediatric KTS patients were reviewed. All patients received care at a specialized vascular clinic within a multicenter tertiary care system. Variables studied included age, age at KTS diagnosis, gender, urologic involvement, and age of urologic complication.

RESULTS

58 patients were identified. 33 were male and 25 were female. 10 patients had GU findings. Three of these patients had multifocal GU involvement (greater than 1 finding). Urologic manifestations were diverse with 9 distinct diagnoses involving 6 unique organs. Renal, vesical and scrotal pathologies were most common. Hematuria was the most common presenting symptom in 30% (3/10). Previously unreported findings (labial swelling, renal lymphatic cysts) were identified. The average age of KTS diagnosis was 4.9 years. The average age of documented GU complication and involvement was 7.6 years.

CONCLUSION

Significant GU complications due to KTS can occur in the pediatric population. Early clinical and imaging characterization of these conditions is important for management, family education and early intervention strategies.