Cantu Syndrome Research Articles

K ATP Channels and Cardiovascular Disease

ATP-sensitive potassium (KATP) channels were first discovered in the heart 30 years ago. Reconstitution of KATP channel activity by coexpression of members of the pore-forming inward rectifier gene family (Kir6.1, KCNJ8, and Kir6.2 KCNJ11) with sulfonylurea receptors (SUR1, ABCC8, and SUR2, ABCC9) of the ABCC protein subfamily has led to the elucidation of many details of channel gating and pore properties. In addition, the essential roles of Kir6.x and SURx subunits in generating cardiac and vascular KATP(2) and the detrimental consequences of genetic deletions or mutations in mice have been recognized. However, despite this extensive body of knowledge, there has been a paucity of defined roles of KATP subunits in human cardiovascular diseases, although there are reports of association of a single Kir6.1 variant with the J-wave syndrome in the ECG, and 2 isolated studies have reported association of loss of function mutations in SUR2 with atrial fibrillation and heart failure. Two new studies convincingly demonstrate that mutations in the SUR2 gene are associated with Cantu syndrome, a complex multi-organ disorder characterized by hypertrichosis, craniofacial dysmorphology, osteochondrodysplasia, patent ductus arteriosus, cardiomegaly, pericardial effusion, and lymphoedema. This realization of previously unconsidered consequences provides significant insight into the roles of the KATP channel in the cardiovascular system and suggests novel therapeutic possibilities.

Cantu syndrome and lymphoedema

Three female patients with Cantu syndrome were studied, two of whom were adults presenting with the complication of lymphoedema, as described earlier in a male patient with this syndrome. The aim of this study is to report the clinical characteristics of these three new cases and to emphasize that lymphoedema, as observed in two of the patients described here, has been observed in 11.5% of patients with Cantu syndrome and that heterochromia iridis, observed in one patient, is probably a new feature of this condition.

Pulmonary hypertension secondary to partial pulmonary venous obstruction in a child with Cantu syndrome

We report on an African-American male with Cantu syndrome who required a pericardial window for a significant pericardial effusion in infancy and was subsequently found to have partial pulmonary venous obstruction (PVO) leading to pulmonary hypertension. Measurement of bilateral pulmonary capillary wedge pressures is important to uncover partial PVO.

Cantu syndrome in a woman and her two daughters: Further confirmation of autosomal dominant inheritance and review of the cardiac manifestations

Cantu syndrome, or hypertrichosis-osteodysplasia-cardiomegaly syndrome, is a rare disorder of unknown etiology, associated with hypertrichosis, characteristic facial features, skeletal abnormalities, cardiomegaly, and occasional pericardial effusions. Although autosomal recessive inheritance was originally proposed, a man with three affected children has been reported, making autosomal dominant inheritance likely. We report on a woman and her two daughters with Cantu syndrome, further confirming dominant inheritance. All three of our patients have cardiac involvement, and symptomatic pericardial effusions requiring surgical intervention occurred in the mother and one of her daughters. Chromosome microarray analysis was normal in one of the girls. The etiology of the cardiomegaly and pericardial effusions in Cantu syndrome is unknown. We review all previously reported cases of Cantu syndrome and the associated cardiac manifestations.

A patient with monosomy 1p36, atypical features and phenotypic similarities with Cantu syndrome

We report on a 16-year-old boy with a distal 1p36 deletion with some clinical features consistent with Cantu syndrome (OMIM#239850). He also has hypercholesterolemia, type II diabetes, recurrent bony fractures, and non-alcoholic steatohepatitis, not previously described in either condition. The 1p36 deletion was detected in a screen of all chromosome subtelomeres using multiplex ligation-dependent probe amplification and was verified using FISH with a region-specific BAC clone. We suggest that patients suspected of having Cantu syndrome, especially those with unusual or more severe manifestations be analyzed for distal 1p36 deletions.