MELK-a conserved kinase: functions, signaling, cancer, and controversy.

Maternal embryonic leucine zipper kinase (MELK) is a highly conserved serine/threonine kinase initially found to be expressed in a wide range of early embryonic cellular stages, and as a result has been implicated in embryogenesis and cell cycle control. Recent evidence has identified a broader spectrum of tissue expression pattern for this kinase than previously appreciated. MELK is expressed in several human cancers and stem cell populations. Unique spatial and temporal patterns of expression within these tissues suggest that MELK plays a prominent role in cell cycle control, cell proliferation, apoptosis, cell migration, cell renewal, embryogenesis, oncogenesis, and cancer treatment resistance and recurrence. These findings have important implications for our understanding of development, disease, and cancer therapeutics. Furthermore understanding MELK signaling may elucidate an added dimension of stem cell control

C-Reactive Protein to Albumin Ratio and Albumin to Fibrinogen Ratio in Rheumatoid Arthritis Patients

Objective: the albumin to fibrinogen ratio (AFR) and the C-reactive protein (CRP) to albumin ratio (CAR) have been proposed as markers of systemic inflammation. The goal of this study was to differentiate rheumatoid arthritis (RA) patients from healthy people and to study the association between AFR/CAR and DAS28 in RA.Patients and methods. A case control study including 30 RA patients and 30 healthy controls was performed. Fibrinogen, albumin, CRP and erythrocyte sedimentation rate (ESR) were measured. We calculated CAR and AFR in each group and compared them. Correlations of AFR, and CAR with disease activity were examined. Receiver operation characteristic (ROC) curves of AFR and CAR were also used to detect cutoffs for disease activity assessment.Results and discussion. CAR was higher while AFR was lower in RA patients than in control group. ROC curve analyses showed that CAR can be used to detect disease activity of RA at cut off 2.66 with sensitivity 81.3% and specificity 64.3% with an area under the curve (AUC) 0.78. So, CAR was a fair parameter to discriminate disease activity among RA patients. AFR has AUC 0.62, sensitivity 87.5% and specificity 42.9% at cutoff value 5.96. So, in our group AFR was a poor indicator to discriminate disease activity among RA patients.Conclusion. AFR and CAR have been recently proposed as inflammatory markers for assessment of disease activity in RA. AFR and CAR are simple, and inexpensive biomarkers, they also can be rapidly evaluated. CAR was found to be a fair parameter to depict disease activity in RA patients. AFR poorly depicted RA activity.Objective: the albumin to fibrinogen ratio (AFR) and the C-reactive protein (CRP) to albumin ratio (CAR) have been proposed as markers of systemic inflammation. The goal of this study was to differentiate rheumatoid arthritis (RA) patients from healthy people and to study the association between AFR/CAR and DAS28 in RA.Patients and methods. A case control study including 30 RA patients and 30 healthy controls was performed. Fibrinogen, albumin, CRP and erythrocyte sedimentation rate (ESR) were measured. We calculated CAR and AFR in each group and compared them. Correlations of AFR, and CAR with disease activity were examined. Receiver operation characteristic (ROC) curves of AFR and CAR were also used to detect cutoffs for disease activity assessment.Results and discussion. CAR was higher while AFR was lower in RA patients than in control group. ROC curve analyses showed that CAR can be used to detect disease activity of RA at cut off 2.66 with sensitivity 81.3% and specificity 64.3% with an area under the curve (AUC) 0.78. So, CAR was a fair parameter to discriminate disease activity among RA patients. AFR has AUC 0.62, sensitivity 87.5% and specificity 42.9% at cutoff value 5.96. So, in our group AFR was a poor indicator to discriminate disease activity among RA patients.Conclusion. AFR and CAR have been recently proposed as inflammatory markers for assessment of disease activity in RA. AFR and CAR are simple, and inexpensive biomarkers, they also can be rapidly evaluated. CAR was found to be a fair parameter to depict disease activity in RA patients. AFR poorly depicted RA activity

The Effect of Anterior Stromal Puncture Using Q-Switched Nd:YAG Laser on Corneal Wound Healing

Introduction: Recurrent corneal erosion occurs when the wounded corneal epithelium failed to adhere to the underlying stroma. Therefore, this work aimed to assess the effect of treatment of corneal injury using Q- switched Nd:YAG laser.  Method: Twenty one New Zealand male rabbits weighing 2-2.5 kg and 3 months old were classified into three main groups. The control group: did not received any treatment (n=3 rabbits). The rest of the animals (n= 18 rabbits), corneal epithelium was injured by syringe needle and blade 15 and divided into:(A) Normal healing group: which was divided into three subgroups (n=3 rabbits each), and the animals were left for normal healing for1 day, 1 week, and 4 weeks respectively, (B) Laser treated group: divided into three subgroups (n=3 rabbits each) and subjected to anterior stromal puncture using Q-switched Nd: YAG laser on corneal sub-epithelium or superficial stroma, and the animals were left for 1 day, 1 week, and 4 weeks respectively. After the demonstrated periods, the corneas were isolated for estimation of total protein content, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), total antioxidative capacity (TAC), total oxidative capacity (TOC) and oxidative stress index (OSI).Results: The present results of corneal total protein showed increment in the percentage change in normal healed groups after 1 day, 1 week and 4 weeks by values of 93%, 68% and 39%. In Q-switched Nd: YAG laser treated group the results showed better improvement in corneal protein than normal healed group with percentage changes of 58%, 29%, and 7.5% respectively. In SDS- PAGE, a protein band at 110 KD appeared in the migrating epithelium for both normal healed group and Q-switched Nd:YAG laser treated group with changes in the peaks intensities at middle and  low molecular weight regions. Moreover, after 4 weeks the peak at 110 KD disappeared in the wounded epithelium treated with Q-switched Nd:YAG. After four weeks, the OSI in laser treated corneas showed pronounced balance between antioxidative capacity and oxidative capacity.Conclusion: Anterior stromal puncture by Q-switched Nd:YAG laser is an effective, simple, safe and promising procedure to treat recurrent corneal erosion than normal healing

FOXD1-ALDH1A3 signaling is a determinant for the self-renewal and tumorigenicity of mesenchymal glioma stem cells

Glioma stem-like cells (GSC) with tumor-initiating activity orchestrate the cellular hierarchy in glioblastoma and engender therapeutic resistance. Recent work has divided GSC into two subtypes with a mesenchymal (MES) GSC population as the more malignant subtype. In this study, we identify the FOXD1-ALDH1A3 signaling axis as a determinant of the MES GSC phenotype. The transcription factor FOXD1 is expressed predominantly in patient-derived cultures enriched with MES, but not with the proneural GSC subtype. shRNA-mediated attenuation of FOXD1 in MES GSC ablates their clonogenicity in vitro and in vivo. Mechanistically, FOXD1 regulates the transcriptional activity of ALDH1A3, an established functional marker for MES GSC. Indeed, the functional roles of FOXD1 and ALDH1A3 are likely evolutionally conserved, insofar as RNAi-mediated attenuation of their orthologous genes in Drosophila blocks formation of brain tumors engineered in that species. In clinical specimens of high-grade glioma, the levels of expression of both FOXD1 and ALDH1A3 are inversely correlated with patient prognosis. Finally, a novel small-molecule inhibitor of ALDH we developed, termed GA11, displays potent in vivo efficacy when administered systemically in a murine GSC-derived xenograft model of glioblastoma. Collectively, our findings define a FOXD1-ALDH1A3 pathway in controling the clonogenic and tumorigenic potential of MES GSC in glioblastoma tumors

Medullary thyroid carcinoma presenting as a supraglottic mass.

© 2015 Vendome Group, LLC. We report a rare case of medullary thyroid carcinoma that presented as a metastasis to the supraglottic larynx. A 92-year-old man with a 3-month history of voice change and airway obstruction was diagnosed with medullary thyroid carcinoma metastatic to the supraglottis. Excision of the mass, total thyroidectomy, and elective neck dissection were recommended, but the patient declined because of his advanced age. Medullary carcinoma of the thyroid gland is a rare neuroendocrine tumor with a poor prognosis when associated with a distant metastasis. To the best of our knowledge, this is the first case of a medullary carcinoma of the thyroid presenting as a supraglottic mass. Total thyroidectomy, neck dissection, and surgical excision of the entire tumor comprise the treatment of choice

Medullary thyroid carcinoma presenting as a supraglottic mass

© 2015 Vendome Group, LLC. We report a rare case of medullary thyroid carcinoma that presented as a metastasis to the supraglottic larynx. A 92-year-old man with a 3-month history of voice change and airway obstruction was diagnosed with medullary thyroid carcinoma metastatic to the supraglottis. Excision of the mass, total thyroidectomy, and elective neck dissection were recommended, but the patient declined because of his advanced age. Medullary carcinoma of the thyroid gland is a rare neuroendocrine tumor with a poor prognosis when associated with a distant metastasis. To the best of our knowledge, this is the first case of a medullary carcinoma of the thyroid presenting as a supraglottic mass. Total thyroidectomy, neck dissection, and surgical excision of the entire tumor comprise the treatment of choice

Endogenous 2-oxoacids differentially regulate expression of oxygen sensors.

Adaptations to change in oxygen availability are crucial for survival of multi-cellular organisms and are also implicated in several disease states. Such adaptations rely upon gene expression regulated by the heterodimeric transcription factors HIFs (hypoxia-inducible factors). Enzymes that link changes in oxygen tensions with the stability and transcriptional activity of HIFs are considered as oxygen sensors. These enzymes are oxygen-, iron- and 2-oxoglutarate-dependent dioxygenases that hydroxylate key proline and asparagine residues in HIFalpha subunits. The constitutive inhibitory action of these enzymes on HIFs is relieved by hypoxia and by agents that displace iron or 2-oxoglutarate. Two of the enzymes, HPH (HIF prolyl hydroxylase)-1 and HPH-2, are known to be inducible by hypoxia in a HIF-dependent manner. This suggests the existence of a novel feedback loop for adjusting hypoxia-regulated gene expression. We have recently shown that HIF-1alpha stability, HIF-1 nuclear translocation and HIF-mediated gene expression in human glioma cell lines can be stimulated by pyruvate independently of hypoxia. In the present study we show that the endogenous 2-oxoacid oxaloacetate can also activate HIF-mediated gene expression. Pyruvate and oxaloacetate treatment of cells also up-regulates HPH-1 and HPH-2, but not HPH-3 or the HIF asparaginyl hydroxylase FIH-1 (factor inhibiting HIF). Regulation of HIF-1 and the expression of HPH homologue genes can thus be influenced by specific glycolytic and tricarboxylic acid cycle metabolites. These findings may underlie important interactions between oxygen homoeostasis, glycolysis, the tricarboxylic acid cycle and gluconeogenesis

MELK—a conserved kinase: functions, signaling, cancer, and controversy

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Araguspongine C Induces Autophagic Death in Breast Cancer Cells through Suppression of c-Met and HER2 Receptor Tyrosine Kinase Signaling

Receptor tyrosine kinases are key regulators of cellular growth and proliferation. Dysregulations of receptor tyrosine kinases in cancer cells may promote tumorigenesis by multiple mechanisms including enhanced cell survival and inhibition of cell death. Araguspongines represent a group of macrocyclic oxaquinolizidine alkaloids isolated from the marine sponge Xestospongia species. This study evaluated the anticancer activity of the known oxaquinolizidine alkaloids araguspongines A, C, K and L, and xestospongin B against breast cancer cells. Araguspongine C inhibited the proliferation of multiple breast cancer cell lines in vitro in a dose-dependent manner. Interestingly, araguspongine C-induced autophagic cell death in HER2-overexpressing BT-474 breast cancer cells was characterized by vacuole formation and upregulation of autophagy markers including LC3A/B, Atg3, Atg7, and Atg16L. Araguspongine C-induced autophagy was associated with suppression of c-Met and HER2 receptor tyrosine kinase activation. Further in-silico docking studies and cell-free Z-LYTE assays indicated the potential of direct interaction between araguspongine C and the receptor tyrosine kinases c-Met and HER2 at their kinase domains. Remarkably, araguspongine C treatment resulted in the suppression of PI3K/Akt/mTOR signaling cascade in breast cancer cells undergoing autophagy. Induction of autophagic death in BT-474 cells was also associated with decreased levels of inositol 1,4,5-trisphosphate receptor upon treatment with effective concentration of araguspongine C. In conclusion, results of this study are the first to reveal the potential of araguspongine C as an inhibitor to receptor tyrosine kinases resulting in the induction of autophagic cell death in breast cancer cells

Erythropoietin Signaling Promotes Invasiveness of Human Head and Neck Squamous Cell Carcinoma

Erythropoietin (Epo) is used for managing anemia in cancer patients. However, recent studies have raised concerns for this practice. We investigated the expression and function of Epo and the erythropoietin receptor (EpoR) in tumor biopsies and cell lines from human head and neck cancer. Epo responsiveness of the cell lines was assessed by Epoetin-α-induced tyrosine phosphorylation of the Janus kinase 2 (JAK2) protein kinase. Transmigration assays across Matrigel-coated filters were used to examine the effects of Epoetin-α on cell invasiveness. In 32 biopsies, we observed a significant association between disease progression and expression of Epo and its receptor, EpoR. Expression was highest in malignant cells, particularly within hypoxic and infiltrating tumor regions. Although both Epo and EpoR were expressed in human head and neck carcinoma cell lines, only EpoR was upregulated by hypoxia. Epoetin-α treatment induced prominent JAK2 phosphorylation and enhanced cell invasion. Inhibition of JAK2 phosphorylation reduced both basal and Epo-induced invasiveness. Our findings support a role for autocrine or paracrine Epo signaling in the malignant progression and local invasiveness of head and neck cancer. This mechanism may also be activated by recombinant Epo therapy and could potentially produce detrimental effects in rhEpo-treated cancer patients