Multicentric Osteolysis, Nodulosis, and Arthropathy in two unrelated children with matrix metalloproteinase 2 variants: Genetic-skeletal correlations

Biological Activity of Biomarkers Associated With Metastasis in Osteosarcoma Cell Lines

INTRODUCTION

Osteosarcoma, a highly aggressive bone cancer primarily affecting children and young adults, remains a significant challenge in clinical oncology. Metastasis stands as the primary cause of mortality in osteosarcoma patients. However, the mechanisms driving this process remain incompletely understood. Clarifying the molecular pathways involved in metastasis is essential for enhancing patient prognoses and facilitating the development of targeted therapeutic strategies.

METHODS

RNA sequencing (RNA-Seq) analysis was employed to compare three conditions, hFOB1.19 versus Saos-2, hFOB1.19 versus SJSA-1, and Saos-2 versus SJSA-1, involving non-cancer osteoblasts (hFOB1.19) and highly metastatic osteosarcoma cell lines (Saos-2 and SJSA-1). Additionally, ENA datasets of RNA-Seq from osteosarcoma biopsies were included. Differentially expressed genes (DEGs) were identified and analyzed through enrichment pathway analysis and protein-protein interaction (PPI) networks. Additionally, for gene candidates, a biochemical evaluation was performed.

RESULTS

DEGs associated with biological functions pertinent to migration, invasion, and metastasis in osteosarcoma were identified. Notably, matrix metalloproteinase-2 (MMP-2) emerged as a promising candidate. Both canonical or full-length (FL-mmp-2) and N-terminal truncated (NTT-mmp-2) isoforms were discerned in biopsies. Moreover, MMP-2's activity was characterized in cell lines. Additionally, mRNA expression of voltage-gated sodium channels (NaVs) and voltage-gated potassium channels (KVs) was detected, and their functional expression was validated using patch clamp techniques. Evaluation of cell line migration and invasion capacities revealed their reduction in the presence of ion channel blockers (TTX and TEA) and MMP inhibitor (GM6001).

CONCLUSIONS

The gene functional enrichment analysis of DEGs enabled the identification of interaction networks in osteosarcoma, thereby revealing potential biomarkers. Moreover, the elucidated co-participation of TTX-sensitive NaVs and MMP-2 in facilitating migration and invasion suggests their suitability as novel prognostic biomarkers for osteosarcoma. Additionally, this study introduces a model delineating the potential interaction mechanism among ion channels, MMP-2, and other crucial factors in the metastatic cascade of osteosarcoma.

Multicentric Osteolysis Nodulosis and Arthropathy (MONA): A Case Series and Review of the Literature

Multicentric Osteolysis Nodulosis and Arthropathy (MONA) is a rare skeletal disorder driven by mutations in the MMP2 gene, leading to bone and joint degradation. This case series presents three unique MONA cases, highlighting clinical, radiological, and genetic aspects. These insights shed light on the complexities of MONA, aiding early diagnosis and multidisciplinary management. Case 1 is a 13-year-old male, born to consanguineous parents, presented with a 5-year history of progressive joint deformities, pain, and difficulty walking. Initially diagnosed as juvenile idiopathic arthritis (JIA), despite treatment, his symptoms persisted. Examination revealed multiple clinical findings, including joint contractures and nodules. Genetic analysis identified a pathogenic variant in the MMP2 gene, confirming MONA. Case 2 and Case 3 were two siblings, aged 12 and 17 years respectively, who presented progressive joint contractures in their hands and feet since early childhood. Clinical examinations revealed contractures and subcutaneous nodules. Genetic analysis confirmed MONA with a shared homozygous pathogenic MMP2 variant, emphasising the genetic basis of this rare disorder.

Multimodal Imaging of Posterior Corneal Opacities in Multicentric Osteolysis Nodulosis and Arthropathy (MONA)

Purpose

Multicentric osteolysis nodulosis and arthropathy (MONA) syndrome is a rare autosomal recessive skeletal dysplasia. Caused by mutations in the matrix metalloproteinase 2 gene (MMP2) on chromosome 16q12, this syndrome has infrequently been associated with ophthalmic manifestations. Corneal opacities have been reported but not described or documented in detail.

Methods

Complete ophthalmologic examination and multimodal anterior segment imaging were used to characterize the corneal findings in a patient with MONA syndrome.

Results

A 19-year-old with MONA syndrome was referred for an eye exam based upon MONA screening recommendations. Visually insignificant peripheral corneal opacities were noted. Anterior segment optical coherence tomography (AS-OCT) demonstrated posterior stromal and endothelial hyperreflectivity. Confocal microscopy demonstrated an acellular peripheral endothelium with a normal central endothelium.

Conclusions

Corneal opacities can occur with MONA syndrome, which is caused by mutations in the MMP2 gene. In the patient presented here, the corneal opacities are peripheral, deep stromal, with sparing of the anterior stroma and epithelium.

A clinical and molecular characterization of a Pakistani family with multicentric osteolysis, nodulosis and arthropathy (MONA) syndrome

Multicentric osteolysis nodulosis and arthropathy (MONA) is a rare skeletal dysplasia characterized primarily by progressive osteolysis, particularly affecting the carpal and tarsal bones, accompanied by osteoporosis. In addition, it features subcutaneous nodules on the palms and soles, along with the progressive onset of arthropathy, encompassing joint contractures, pain, swelling and stiffness. It is caused by a deficiency of the Matrix Metalloproteinase-2 (MMP2). In the current study we present a comprehensive clinical, radiological, genetic and in silico analysis of MONA in a consanguineous Pakistani family. Clinical and radiological examinations of the three severely affected siblings demonstrated a progressive MONA syndrome with phenotypic variability. The patients presented unusual facial appearance, thickened skin, severe short stature, short hands and feet. Radiographs revealed extensive bone deformities affecting upper and lower arms, legs, vertebrae and hip. Genetic analysis revealed a homozygous missense variant [c.539 A > T p.(Asp180Val)] in the MMP2 gene. In silico findings suggested a mutant MMP2 protein with a decreased stability and an altered pattern of interactions. Our findings add to the existing literature on the skeletal phenotype of MONA syndrome, including the specific clinical and radiological patterns observed. Moreover, the study will aid in genetic counseling and accurate diagnosis of families affected by the same disorder within the Pakistani population.

Clinical, radiographic and molecular characterization of two unrelated families with multicentric osteolysis, nodulosis, and arthropathy

BACKGROUND

Multicentric osteolysis nodulosis and arthropathy (MONA) is a rare autosomal recessive disorder characterized by marked progressive bone loss and joint destruction resulting in skeletal deformities. MONA is caused by MMP2 deficiency. Here we report clinical and molecular analyses of four patients in two families from Pakistan and Finland.

METHODS

Clinical analyses including radiography were completed and blood samples were collected. The extracted DNA was subjected to whole-exome analysis or target gene sequencing. Segregation analyses were performed in the nuclear pedigree. Pathogenicity prediction scores for the selected variants and conservation analyses of affected amino acids were observed.

RESULTS

The phenotype in the four affected individuals was consistent with multicentric osteolysis or MONA, as the patients had multiple affected joints, osteolysis of hands and feet, immobility of knee joint and progressive bone loss. Long-term follow up of the patients revealed the progression of the disease. We found a novel MMP2 c.1336 + 2T > G homozygous splice donor variant segregating with the phenotype in the Pakistani family while a MMP2 missense variant c.1188 C > A, p.(Ser396Arg) was homozygous in both Finnish patients. In-silico analysis predicted that the splicing variant may eventually introduce a premature stop codon in MMP2. Molecular modeling for the p.(Ser396Arg) variant suggested that the change may disturb MMP2 collagen-binding region.

CONCLUSION

Our findings expand the genetic spectrum of Multicentric osteolysis nodulosis and arthropathy. We also suggest that the age of onset of this disorder may vary from childhood up to late adolescence and that a significant degree of intrafamilial variability may be present.

Multicentric Osteolysis Nodulosis Arthropathy Syndrome Simulating Juvenile Idiopathic Arthritis in an Adult Female: A Case Report and a Literature Review

Multicentric osteolysis, nodulosis, and arthropathy (MONA) syndrome is one of the rare genetic skeletal dysplasias, inherited as an autosomal recessive disorder, which predominantly involves carpal and tarsal bones with characteristic osteolytic lesions and can be misdiagnosed as juvenile idiopathic arthritis or rheumatoid arthritis. MONA syndrome includes diseases involving two genes: the matrix metalloproteinase 2 (MMP2) gene and matrix metalloproteinase 14 (MMP14). Both genes are assumed to cause phenotype variants of the same disease. Older patients may manifest some arthritic features, especially in the wrist, and minute pathological fractures can occur as well. These patients may be misdiagnosed as inflammatory arthritis and physicians might prescribe corticosteroid and disease-modifying immunosuppressive agents. Therefore, physicians should carefully evaluate genetic skeletal dysplasia to make a correct diagnosis and avoid unnecessary pharmacological intervention. We report a case of MONA syndrome in an adult female who came to our facility for an intensive rehabilitation program.

Association of MMP-2 and MMP-9 Polymorphisms with Diabetes and Pathogenesis of Diabetic Complications

Type 2 diabetes mellitus (T2D) affects millions of people around the world, and its complications have serious health consequences. In addition to external factors, the causes of morbidity and increased risk were also sought in the variability of the human genome. A phenomenon that can answer these questions is the occurrence of single-nucleotide polymorphisms (SNP). They constitute a field for research into genetic determinants responsible for the increase in the risk of the discussed metabolic disease. This article presents the outline of two enzymes: metalloproteinases 2 and 9 (MMP-2, MMP-9), their biological activity and the effect caused by differences in individual alleles in the population, as well as the reports on the importance of these DNA sequence variations in the occurrence of diabetes mellitus type 2 and associated conditions. The results of the conducted research indicate a relationship between two MMP-2 polymorphisms (rs243865, rs243866) and two MMP-9 polymorphisms (rs3918242, rs17576) and the presence of T2D. This could offer a promising possibility to use them as predictive and diagnostic markers. However, due to the low number of reports, more research is needed to clearly confirm the link between these SNPs and diabetes.