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Biology subjects

Kanji, R.

Publications and source records attributed to Kanji, R..

3 recordsLinked to original sources

Pannexin 1 inhibition reduces tumorigenic properties of patient-derived glioblastoma cells through the HIPPO and Wnt signalling pathways

Glioblastoma (GBM) is the most common primary brain tumour, with a median survival of 12-18 months, highlighting a need for new treatment targets. We observed that pannexin 1 (PANX1), a channel-forming glycoprotein important in purinergic signalling, is upregulated in GBM compared to normal tissue and expressed throughout patient tumours. Western blot analysis of patient-derived GBM cell lines revealed significantly increased PANX1 expression in these primary lines compared to brain tissue and control glial cells. Bulk RNA-sequencing compared the gene expression of GBM cells devoid of PANX1 via CRISPR/Cas9 deletion (PANX1-KO) compared to controls. Gene Ontology and KEGG gene set analyses revealed PANX1-KO in GBM cells affects cell surface and cell junction components, processes, and pathways, including the HIPPO pathway, in addition to critically downregulating {beta}-catenin mRNA and other components of the Wnt pathway. The deletion of PANX1 resulted in a disruption of the {beta}-catenin protein and a dramatic reduction in migration and cell growth. Pharmacological inhibition of PANX1 in GBM cells with Probenecid (PBN) and Spironolactone (SPIR) demonstrated a significant reduction in live cell numbers and migration via scratch assay. Both blockers dramatically decreased F-actin filament formation, and the cellular localization of beta-catenin became more intracellular compared to controls. Xenografted GBM tumours showed a reduction in tumour cell viability by bioluminescent imaging and reduced hemorrhaging incidence when treated with PBN. These new insights support further investigation of PANX1 as a potential GBM therapeutic target and its role in multiple cancer signaling pathways that regulate this devastating disease.

cancer biology↗

Aged male and female Panx3 KO mice develop severe osteoarthritis independent of forced mechanical use.

Osteoarthritis (OA) is a multi-factorial disease associated with aging. As the molecular mechanisms underpinning the pathogenesis of this disease are unclear, there are no disease-modifying drugs to combat OA. Pannexin 3 (PANX3) has been shown to promote cartilage loss during posttraumatic OA. In contrast, the ablation of Panx3 in male mice results in spontaneous full-thickness cartilage lesions at 24 months of age. While protected from traumatic intervertebral disc (IVD) degeneration, Panx3 knockout (KO) mice show signs of IVD disease with altered disc mechanics. Whether the deleterious effects of ablating Panx3 in aging is the result from accumulated mechanical damage is unknown. We used male and female wildtype (WT) and global Panx3 KO C57Bl6 mice aged to 18 months of age. Mice were then randomized to sedentary (SED) or forced treadmill running (FEX) for 6 weeks. Knee joint tissues including patellar tendon, quadriceps and distal patellar enthesis, and synovium were analyzed histologically and through micro-CT, along with lumbar spine IVDs. Half of male and female sedentary Panx3 KO mice developed full-thickness cartilage lesions, severe synovitis, and ectopic fibrocartilage deposition and calcification of the knee joints in comparison to all other conditions. Panx3 KO mice with severe OA show signs of quadriceps and patellar enthesitis, characterized by bone and marrow formation. Forced treadmill running did not seem to exacerbate these phenotypes in male or female Panx3 KO mice; however, it may have contributed to the development of lateral compartment OA. The IVDs of aged Panx3 KO mice displayed no apparent differences to control mice, and forced treadmill running had no further effects in either genotype. We conclude that aged Panx3 KO mice show features of late-stage primary OA including full-thickness cartilage erosion, severe synovitis, and enthesitis. These data suggest that the deletion of Panx3 is deleterious to synovial joint health in aging. LAY SUMMARYOsteoarthritis is a common joint disease, and its incidence can increase with aging. As such, no drugs are available to treat its progression. Recently, we discovered that cellular channels composed of Pannexin 3 (PANX3) proteins may contribute to the health of joint tissues. In this study, we propose a new model for age-related primary OA, using histology, microCT, and pathology assessments under sedentary and forced exercise conditions. We found that aged mice lacking the channel protein PANX3 developed late-stage OA, including severe cartilage loss, joint inflammation, and tendon attachment damage. Half of the sedentary PANX3-deficient mice showed these changes, along with abnormal bone growth. Treadmill running did not make the condition worse but may have caused additional joint damage in some areas. The spine, however, remained unaffected. These findings suggest that deleting Panx3 harms joint health with aging. Importantly, this mouse model mimics human primary OA, even without added factors like diet changes or forced exercise.

physiology↗

Pannexin 3 deletion in mice results in knee osteoarthritis and intervertebral disc degeneration after forced treadmill running.

Pannexin 3 (Panx3) is a glycoprotein that forms mechanosensitive channels expressed in chondrocytes and annulus fibrosus cells of the intervertebral disc (IVD). Evidence suggests Panx3 plays contrasting roles in traumatic versus aging osteoarthritis (OA) and intervertebral disc degeneration (IDD). However, whether its deletion influences the response of joint tissue to mechanical stress is unknown. The purpose of this study was to determine if Panx3 deletion in mice causes increased knee joint OA and IDD after forced treadmill running. Male and female wildtype (WT) and Panx3 knockout (KO) mice were randomized to either a no exercise group (sedentary; SED) or daily forced treadmill running (forced exercise; FEX) from 24 to 30 weeks of age. Knee cartilage, tibial secondary ossification center and IVD histopathology were evaluated by histology. Both male and female Panx3 KO mice developed larger superficial defects of the tibial cartilage after forced treadmill running compared to SED WT mice. Additionally, both male and female Panx3 KO mice developed greater bone area of the tibial secondary ossification center with running. In the lower lumbar spine, both male and female Panx3 KO mice developed histopathological features of IDD after running compared to SED WT mice. These findings suggest that the combination of deleting Panx3 and forced treadmill running induces OA and causes histopathological changes associated with degeneration of the IVDs in mice.

physiology↗