The role of Asap1 in physiology and tumor metastasis

Tumor progression represents an array of complex events that ultimately lead to metastasis, the end-stage of cancer that is responsible for the majority of cancer-related mortalities. Improved ways to target the spread of cancer are thus imperative to treat cancer effectively. Understanding the mechanisms that regulate the dissemination of cancer cells from the primary site to distant places is a pre-requisite for such strategies. Asap1 (Arf-GAP with SH3-domains, Ankyrin-repeats and PH-domains) was identified by our lab in an unbiased screen to identify genes whose expression is associated with the metastatic phenotype. It was shown to be functionally involved in tumor progression in experimental animal models and this expression was correlated with poor metastasisfree survival and prognosis in colorectal cancer patients. To understand the role of Asap1 in normal physiology and in cancer, in my thesis work I studied Asap1 knockout (Asap1GT/GT) mice, generated in our lab by targeted deletion of the gene. I observed that Asap1GT/GT mice can live to maturity, although there is a reduction in the expected number of homozygous knockout offspring at birth. Deletion of Asap1 results in growth retardation, respiratory distress and reduced angiogenesis in the surviving pups. This physiological phenotype in the absence of Asap1 is transient, and adult Asap1GT/GT mice are morphologically undistinguishable from the wild-type mice.I further studied breast tumor development and metastasis in Asap1GT/GT mice using autochthonous models of breast cancer. My results demonstrate that loss of Asap1 in MMTV-PyMT mice leads to an earlier tumor onset, faster tumor growth and increased metastasis to the lungs. I also examined the effect of ASAP1 deficiency on the behaviour of breast cancer cells and fibroblasts taken from Asap1+/+ and Asap1GT/GT mice. Taken together, my results show that Asap1 is a critical regulator of cellular motility and its absence gives rise to developmental defects in newborn mice.Deficiency of ASAP1 also has tumor cell non-autonomous effects, and leads to increased numbers of metastases in the MMTV-PyMT autochthonous mouse model of breast cancer

Acupuncture in the Management of Orofacial Pain and Related Disorders: A Review

Oro-facial pain and temperomandibular dysfunction are deemed upon as multifaceted problems and can pose major therapeutic problem in dealing with them. Evidence from clinical studies suggests that acupuncture may be useful in the treatment of orofacial pain, temperomandibular dysfunction and related disorders otherwise resistant to conventional treatment modalities.  Acupuncture is an ancient healing technique that has regained its lost popularity in the last two decades. The present paper attempts to review this forbidden procedure and its role in improving the quality of dental care provided to the patients especially in the management of orofacial pain, temperomandibular dysfunction, dental anxiety, gag reflex, xerostomia and trigeminal neuralgia. &nbsp

Loss of ASAP1 in mice impairs adipogenic and osteogenic differentiation of mesenchymal progenitor cells through dysregulation of FAK/Src and AKT signaling

ASAP1 is a multi-domain adaptor protein that regulates cytoskeletal dynamics, receptor recycling and intracellular vesicle trafficking. Its expression is associated with poor prognosis for a variety of cancers, and promotes cell migration, invasion and metastasis. Little is known about its physiological role. In this study, we used mice with a gene-trap inactivated ASAP1 locus to study the functional role of ASAP1 in vivo, and found defects in tissues derived from mesenchymal progenitor cells. Loss of ASAP1 led to growth retardation and delayed ossification typified by enlarged hypertrophic zones in growth plates and disorganized chondro-osseous junctions. Furthermore, loss of ASAP1 led to delayed adipocyte development and reduced fat depot formation. Consistently, deletion of ASAP1 resulted in accelerated chondrogenic differentiation of mesenchymal cells in vitro, but suppressed osteo- and adipogenic differentiation. Mechanistically, we found that FAK/Src and PI3K/AKT signaling is compromised in Asap1GT/GT MEFs, leading to impaired adipogenic differentiation. Dysregulated FAK/Src and PI3K/AKT signaling is also associated with attenuated osteogenic differentiation. Together these observations suggest that ASAP1 plays a decisive role during the differentiation of mesenchymal progenitor cells

Loss of ASAP1 in mice impairs adipogenic and osteogenic differentiation of mesenchymal progenitor cells through dysregulation of FAK/Src and AKT signaling.

ASAP1 is a multi-domain adaptor protein that regulates cytoskeletal dynamics, receptor recycling and intracellular vesicle trafficking. Its expression is associated with poor prognosis for a variety of cancers, and promotes cell migration, invasion and metastasis. Little is known about its physiological role. In this study, we used mice with a gene-trap inactivated ASAP1 locus to study the functional role of ASAP1 in vivo, and found defects in tissues derived from mesenchymal progenitor cells. Loss of ASAP1 led to growth retardation and delayed ossification typified by enlarged hypertrophic zones in growth plates and disorganized chondro-osseous junctions. Furthermore, loss of ASAP1 led to delayed adipocyte development and reduced fat depot formation. Consistently, deletion of ASAP1 resulted in accelerated chondrogenic differentiation of mesenchymal cells in vitro, but suppressed osteo- and adipogenic differentiation. Mechanistically, we found that FAK/Src and PI3K/AKT signaling is compromised in Asap1GT/GT MEFs, leading to impaired adipogenic differentiation. Dysregulated FAK/Src and PI3K/AKT signaling is also associated with attenuated osteogenic differentiation. Together these observations suggest that ASAP1 plays a decisive role during the differentiation of mesenchymal progenitor cells

Effects of a novel peptide Ac-SDKP in radiation-induced coronary endothelial damage and resting myocardial blood flow

Abstract Background Cancer survivors treated with thoracic ionizing radiation are at higher risk of premature death due to myocardial ischemia. No therapy is currently available to prevent or mitigate these effects. We tested the hypothesis that an endogenous tetrapeptide N-acetyl-Ser-Asp-Lys-Pro (Ac-SDKP) counteracts radiation-induced coronary vascular fibrosis and endothelial cell loss and preserves myocardial blood flow. Methods We examined a rat model with external-beam-radiation exposure to the cardiac silhouette. We treated a subgroup of irradiated rats with subcutaneous Ac-SDKP for 18-weeks. We performed cardiac MRI with Gadolinium contrast to examine resting myocardial blood flow content. Upon sacrifice, we examined coronary endothelial-cell-density, fibrosis, apoptosis and endothelial tight-junction proteins (TJP). In vitro, we examined Ac-SDKP uptake by the endothelial cells and tested its effects on radiation-induced reactive oxygen species (ROS) generation. In vivo, we injected labeled Ac-SDKP intravenously and examined its endothelial localization after 4-h. Results We found that radiation exposure led to reduced resting myocardial blood flow content. There was concomitant endothelial cell loss and coronary fibrosis. Smaller vessels and capillaries showed more severe changes than larger vessels. Real-time PCR and confocal microscopy showed radiation-induced loss of TJ proteins including- claudin-1 and junctional adhesion molecule-2 (JAM-2). Ac-SDKP normalized myocardial blood flow content, inhibited endothelial cell loss, reduced coronary fibrosis and restored TJ-assembly. In vitro, Ac-SDKP localized to endothelial cells and inhibited radiation-induced endothelial ROS generation. In vivo, labeled Ac-SDKP was visualized into the endothelium 4-h after the intravenous injection. Conclusions We concluded that Ac-SDKP has protective effects against radiation-induced reduction of myocardial blood flow. Such protective effects are likely mediated by neutralization of ROS-mediated injury, preservation of endothelial integrity and inhibition of fibrosis. This demonstrates a strong therapeutic potential of Ac-SDKP to counteract radiotherapy-induced coronary disease

The Therapeutic Potential of Blocking Galectin-3 Expression in Acute Myocardial Infarction and Mitigating Inflammation of Infarct Region: A Clinical Outcome-Based Translational Study

Introduction: Increased galectin-3 is associated with ischemic cardiomyopathy, although its role in early remodeling post-myocardial infarction (MI) has not been fully elucidated. There are no data demonstrating that blocking galectin-3 expression would have an impact on the heart and that its relationship to remodeling is not simply an epiphenomenon. The direct association between galectin-3 and myocardial inflammation, dysfunction, and adverse cardiovascular outcomes post-MI was examined using clinical and translational studies. Methods: We performed expression analysis of 9753 genes in murine model of acute MI. For galectin-3 loss of function studies, homozygous galectin-3 knock-out (KO) mice were subjected to coronary artery ligation procedure to induce acute MI (MI, N = 6; Sham, N = 6). For clinical validation, serum galectin-3 levels were measured in 96 patients with ST-elevation MI. Echocardiographic and angiographic parameters of myocardial dysfunction and 3-month composite outcome including mortality, recurrent MI, stroke, and heart failure hospitalization were measured. Results: In the infarct regions of murine models, galectin-3 was a robustly expressed gene. Elevated galectin-3 expression strongly correlated with macrophage-mediated genes. Galectin-3 KO mice showed reduced myocardial macrophage infiltration after acute MI. Galectin-3 levels were higher in patients with early systolic dysfunction, and predicted 3-month major adverse cardiovascular events (area under the curve [AUC]: 0.917 ± 0.063; P  = .001). Conclusions: Galectin-3 is directly associated with early myocardial inflammation post-MI and may represent a potential target for therapeutic inhibition

Supplementary_Material – Supplemental material for The Therapeutic Potential of Blocking Galectin-3 Expression in Acute Myocardial Infarction and Mitigating Inflammation of Infarct Region: A Clinical Outcome-Based Translational Study

<p>Supplemental material, Supplementary_Material for The Therapeutic Potential of Blocking Galectin-3 Expression in Acute Myocardial Infarction and Mitigating Inflammation of Infarct Region: A Clinical Outcome-Based Translational Study by Wassim Mosleh, Milind R Chaudhari, Swati Sonkawade, Supriya Mahajan, Charl Khalil, Kevin Frodey, Tanvi Shah, Suraj Dahal, Roshan Karki, Rujuta Katkar, W Matthijs Blankesteijn, Brian Page, Saraswati Pokharel, Minhyung Kim and Umesh C Sharma in Biomarker Insights</p