Differentiation Agents Research Articles

Brk/PTK6 and Involucrin Expression May Predict Breast Cancer Cell Responses to Vitamin D3

The process of human embryonic mammary development gives rise to the structures in which mammary cells share a developmental lineage with skin epithelial cells such as keratinocytes. As some breast carcinomas have previously been shown to express high levels of involucrin, a marker of keratinocyte differentiation, we hypothesised that some breast tumours may de-differentiate to a keratinocyte-derived ‘evolutionary history’. To confirm our hypothesis, we investigated the frequency of involucrin expression along with that of Brk, a tyrosine kinase expressed in up to 86% of breast carcinomas whose normal expression patterns are restricted to differentiating epithelial cells, most notably those in the skin (keratinocytes) and the gastrointestinal tract. We found that involucrin, a keratinocyte differentiation marker, was expressed in a high proportion (78%) of breast carcinoma samples and cell lines. Interestingly, tumour samples found to express high levels of involucrin were also shown to express Brk. 1,25-dihydroxyvitamin D3, a known differentiation agent and potential anti-cancer agent, decreased proliferation in the breast cancer cell lines that expressed both involucrin and Brk, whereas the Brk/involucrin negative cell lines tested were less susceptible. In addition, responses to 1,25-dihydroxyvitamin D3 were not correlated with vitamin D receptor expression. These data contribute to the growing body of evidence suggesting that cellular responses to 1,25-dihydroxyvitamin D3 are potentially independent of vitamin D receptor status and provide an insight into potential markers, such as Brk and/or involucrin that could predict therapeutic responses to 1,25-dihydroxyvitamin D3.

Vitamin D: A potent regulator of dopaminergic neuron differentiation and function.

Vitamin D has been identified as a key factor in dopaminergic neurogenesis and differentiation. Consequently, developmental vitamin D (DVD) deficiency has been linked to disorders of abnormal dopamine signalling with a neurodevelopmental basis such as schizophrenia. Here we provide further evidence of vitamin D's role as a mediator of dopaminergic development by showing that it increases neurite outgrowth, neurite branching, presynaptic protein re-distribution, dopamine production and functional release in various in vitro models of developing dopaminergic cells including SH-SY5Y cells, primary mesencephalic cultures and mesencephalic/striatal explant co-cultures. This study continues to establish vitamin D as an important differentiation agent for developing dopamine neurons, and now for the first time shows chronic exposure to the active vitamin D hormone increases the capacity of developing neurons to release dopamine. This study also has implications for understanding mechanisms behind the link between DVD deficiency and schizophrenia.

Carboxymethyl Chitosan-Functionalized Polyaniline/Polyacrylonitrile Nano-Fibers for Neural Differentiation of Mesenchymal Stem Cells

Electroconductive scaffolds based on polyaniline (PANi)/polyacrylonitrile (PAN) were fabricated and surface-functionalized by carboxymethyl chitosan (CMC) as efficient scaffolds for nerve tissue regeneration. The results of scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and water contact angle measurement approved the successful fabrication of CMC-functionalized PANi/PAN-based scaffolds. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured on the scaffolds for 10 d in the presence or absence of β-carotene (βC, 20 µM) as a natural neural differentiation agent. The MTT and SEM results confirmed the attachment and proliferation of hADMSCs on the scaffolds. The expression of MAP2 at the mRNA and protein levels showed the synergic neurogenic induction effect of CMC-functionalization and βC for hADMSCs on the scaffolds. The CMC-functionalized nanofibrous PANi/PAN-based scaffolds are potential candidates for nerve tissue engineering.

Impact of COVID-19 Pandemic on Cancer Patients with Pulmonary Fibrosis on Chemosurveillance

COVID-19 infection and multiplication can be regulated with the aid of vaccines, immunosurveillance, and antiviral medications, such interferon and nucleoside analogs. The main concern with COVID-19 infection is the proliferation of the virus. However, there is no medication to treat pulmonary fibrosis, a life-threatening condition, once it has manifested. To treat critically ill patients with cancer and pulmonary fibrosis, it is imperative to develop cell differentiation agent (CDA) formulations that can kill cancer stem cells. Chemosurveillance for cancer patients no longer functions as intended. As a result, people with cancer are more likely to experience severe symptoms of pulmonary fibrosis. The harm to chemosurveillance caused by cancer treatments that focus on cell death, such as cytotoxic drugs, radiation, and immunotherapy, may gravely accelerate the development of fatal pulmonary fibrosis. To prevent the development of fatal pulmonary fibrosis symptoms, cancer patients should be advised against contracting COVID-19, but, if they do, targeted therapy should be their first choice. The purpose of this study was to highlight the significance of chemosurveillance in determining when fatal pulmonary fibrosis manifests after COVID-19 infection in cancer patients and to conceptualize CDA formulations that can be used to treat both pulmonary fibrosis and cancer. COVID-19 infection causes biological and immunological reactions that are similar to those of a wound, leading to the production of prostaglandins and tumor necrosis factor, which cause respiratory illness symptoms, such as fever and cough, and cachexia symptoms, respectively. This results in the breakdown of chemosurveillance, a natural defense mechanism that ensures optimal wound healing, thus further promoting the development of cancer and pulmonary fibrosis.

Winning Formulas to Fulfill Cancer Moonshot

The objective of this study was to develop winning formulas to fulfill cancer moonshot declared by President Biden on Sept. 12, 2022, the 60th anniversary of the moonshot speech of President Kennedy. The intention of President Biden was to use the spirit of successful moonshot project to salvage the failure of war on cancer project declared by President Nixon in 1971 [1]. Cancer therapies based on killing of cancer cells were the choice of cancer establishments in the past. The choice of killing cancer cells is understandable because the perpetual replication of cancer cells constitutes the most outstanding feature of cancer. Cancer is contributed by multiple factors. Factors other than replication of cancer cells also play essential roles on the development of cancer. Cancer arises as a consequence of wound not healing properly due to the collapse of chemo-surveillance, thus allowing Progenitor Stem Cells (PSCs) to evolve into Cancer Stem Cells (CSCs), and then to progress to faster growing Cancer Cells (CCs) through activation of oncogenes and/or inactivation suppressor genes. Cell killing creates more wounds to aggravate the already bad situation on the functionality of chemo-surveillance, which is an important mechanism to suppress the build-up of cells with abnormal Methylation Enzymes (MEs) that include PSCs, CSCs, and CCs. PSCs and their immediate derivatives CSCs are protected by drug resistant and anti-apoptosis mechanisms. Cytotoxic agents can wipe out CCs but cannot affect CSCs. The damage to chemo-surveillance contributed by cell killing agents allows CSCs to become dominant cells to cause he failure of cancer therapy, thus losing the war on cancer. Cell Differentiation Agent (CDA) formulations are the preparations consisting of Differentiation Inducers (DIs) and Differentiation Helper Inducers (DHIs), plus phenylacetylglutamine as an anti-cachexia agent. Such preparations are perfect cancer drugs to take out both CCs and CSCs by the induction of terminal differentiation through destabilization of abnormal MEs, and to restore the functionality of chemo-surveillance. Cancer therapies mediated by CDA formulations are the nature’s choice to combat cancer that can fulfill the goal of President Biden’s cancer moonshot. CDA formulations, however, cannot make the tumor to disappear, which can be easily accomplished by therapies based on cell killing. President Biden’s goal is very modest, requiring reduction of cancer mortality 50% in 25 years. That goal can be easily accomplished by winning formulas that include CDA formulations and therapies to eliminate or to kill CCs. We offer the following winning formulas: 1. Therapy with CDA-CSC, a preparation made up by an approved DI and an approved DHI, to eradicate CSCs and CCs by the induction of terminal differentiation and to restore the functionality of chemo-surveillance, followed by the surgical removal of the residual tumor. 2. Surgical removal of the primary tumor, followed by the administration of CDA-CSC to prevent recurrence and metastasis, and to restore the functionality of chemo-surveillance. 3. Radiotherapy, immunotherapy, or chemotherapy to kill CCs, followed by the administration of CDA-CSC to eradicate CSCs and to restore the functionality of chemo-surveillance.

Outcomes of Acute Myeloid Leukemia (AML) in Adolescents and Young Adults (AYAs) Compared to Adults in a Referral Center from Lower Myanmar

Introduction Acute myeloid leukemia (AML) is the second most common form of haematological malignancies with high prevalence among all age groups in Myanmar. However, there are very limited data particularly related to AML in adolescents and young adults (AYAs). To fill the gap in AML data from resource-constraint countries and to compare the treatment outcomes of AYAs (15-39 years) with adults (40 years and above), a hospital-based, prospective study was conducted between January 2019 to October 2021, on the cases of AML treated at the North Okkalapa General and Teaching Hospital, one of three referral centers of Myanmar. Methods All cases of AML other than acute promyelocytic leukemia (APL) received two courses of induction containing daunorubicin and cytarabine followed by three courses of consolidation with high dose cytarabine. Treatment of APL included differentiation agents (all-trans-retinoeic acid and arsenic trioxide) based induction with addition of daunorubicin and cytarabine in high-risk cases until remission followed by chemotherapy free consolidation and maintenance up to two years. Patients were followed up for a minimum of one year and overall survival (OS) was calculated using the Kaplan-Meier method. Results A total of 140 including 81 (57.9%) AYAs and 59 (42.1%) adults with newly diagnosed de-novo AML were treated during 34-months period. Median age of AYA AML was 22 years (range-13-39 years) whereas that of adult AML was 54 years (range-40-76 years). There was no gender difference (49.2% versus 50.7%, for male and female). Among AML subtypes, M4 was the commonest subtype (28.5%) and APL, M3 (22.8%) was the second most prevalent AML followed by M2 (18.5%) and M5 (10.7%) subtypes. Cytogenetic data was available in 37 of 108 (34.2 %) non-APL cases with 16.2 %, 67.6% and 16.2 % respectively had good, intermediate, and high-risk cytogenetics. Of 108 non-APL including 61 (56.5%) AYAs and 47 (43.5%) adults, 46 (42.6%) died within one week or during induction and remaining 62 (57.4%) achieved remission at the end of induction. Among 32 APL (20 AYAs and 12 adults), mortality rate was 21.9% due to early death (12.5%) and induction death (9.4%) with only 78% achieved remission after induction. There was no statistically significant difference between the remission rates of AYAs and adults, in both APL (75.0% versus 83.3%, respectively, p=0.68) and non-APL groups (60.65% versus 53.2% respectively, p=0.43). During follow-up, 29 (20.7 %) were lost to follow-up while 6 non-APL AML (5 AYAs and 1 adult, 5.6%) relapsed within one year with 18 of 32 APL (56.3%) and 32 of 108 non-APL AML (29.6%) remained alive at one year. Two-year cumulative survival for AYAs compared to adults was 47% vs 42% respectively for non-APL AML (p=0.42) and 74% vs 83% for APL (p=0.608) with no statistically significant difference between two age groups. Conclusion In this resource limited setting, although having higher proportion of younger population and better prognostic types like APL, remission rate and survival was still low due to higher number of early and induction deaths which could be improved by early diagnosis and better supportive care.

Neurite Outgrowth-Promoting Compounds from the Petals of Paeonia lactiflora in PC12 Cells.

Isorhamnetin-3-O-glucoside and astragalin, flavonol glucosides, were isolated from the petals of Paeonia lactiflora as neurite outgrowth-promoting compounds. Isoquercitrin, formed by demethylating the B ring of isorhamnetin-3-O-glucoside or by adding a hydroxyl group to the B ring of astragalin, was evaluated for neurite outgrowth-promoting activity and was compared with the activities of isorhamnetin-3-O-glucoside and astragalin. The activities of isorhamnetin, kaempferol, and quercetin, aglycones corresponding to isorhamnetin-3-O-glucoside, astragalin, and isoquercitrin, respectively, were also evaluated. Isorhamnetin-3-O-glucoside and astragalin showed much stronger neurite outgrowth-promoting activities than the activities of the other tested flavonoids. They exhibited relatively weak anti-oxidant activities and moderate AChE inhibitory activities compared to the activities of the other tested flavonoids. Isorhamnetin-3-O-glucoside and astragalin promoted morphological neurite outgrowth and the expression of neurofilaments induced by NGF in PC12 cells. Isorhamnetin-3-O-glucoside and astragalin might be candidate compounds as neural differentiation agents in peripheral nerves and functional food ingredients preventing cognitive decline.

Acute promyelocytic leukemia in childhood and adolescence: treatment results of a modified AIDA protocol at a Brazilian center

IntroductionAcute promyelocytic leukemia currently presents an excellent chance of cure with protocols based on all-trans-retinoic acid (ATRA) and anthracycline or only differentiation agents. However, high early mortality rates continue to be reported MethodsBetween 2000 and 2018, patients were enrolled and retrospectively analyzed by medical records. A modified AIDA protocol, with a 1-year shortening of the treatment duration, reduction in the number of drugs and a strategy to reduce early mortality by the postponement of the initiation of anthracyclines were employed. Overall and event-free survival rates and toxicity were analyzed ResultsThirty-two patients were enrolled, of whom 56% were female, with a median age of 12 years and 34% belonged to the high-risk group. Two patients had the hypogranular variant and three had another cytogenetic alteration, in addition to the t(15;17). The median start of the first anthracycline dose was 7 days. There were two early deaths (6%) due to central nervous system (CNS) bleeding. All patients achieved molecular remission after the consolidation phase. Two children relapsed and were rescued by arsenic trioxide and hematopoietic stem cell transplantation. The presence of disseminated intravascular coagulation (DIC) at diagnosis (p = 0.03) was the only factor with survival impact. The five-year event-free survival (EFS) was 84% and 5-year overall survival (OS) was 90% ConclusionThe survival results were comparable to those found in the AIDA protocol, with a low rate of early mortality in relation to the Brazilian reality.

Mesenchymal stem cells encapsulation in chitosan and carboxymethyl chitosan hydrogels to enhance osteo-differentiation.

Recently biomaterials utilized for designing scaffolds in tissue engineering are not cost-effective and eco-friendly. As a result, we design and develop biocompatible and bioactive hydrogels for osteo-tissue regeneration based on the natural polysaccharide chitosan. Three distinct hydrogel components were used for this. Hydrogels networks were created using chitosan 2% (CTS 2%), carboxymethyl chitosan 2% (CMC 2%), and 50:50 mixtures of CTS and CMC (CTS/CMC 50:50). Furthermore, scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), degradation, and swelling behavior of design hydrogels were studied. Also, the cytocompatibility and osteo-differentiation potency were examined by encapsulating mesenchymal stem cells derived from adipose tissue (AMSCs) on the designed hydrogels. According to the findings, our results showed an acceptable pore structure, functional groups, and degradation rate of the designed hydrogels for in vitro evaluation. In addition, employing CMC instead of CTS or adding 50% CMC to the hydrogel component could improve the hydrogel's osteo-bioactivity without the use of external osteogenic differentiation agents. The CMC-containing hydrogel not only caused early osteogenesis but also accelerated differentiation to the maturity phase of osteoblasts.

Shifting gears to differentiation agents in acute promyelocytic leukemia with resource constraints—a cohort study

Background Treatment of acute promyelocytic leukaemia has emerged as a major success in hemato-oncology. While literature from the developed world boasts of outstanding outcomes, there is a paucity of data from the developing world. This study aimed to assess complications and outcomes of acute promyelocytic leukaemia in a resource-constrained setting. Methods We retrospectively collected data from patients diagnosed with APL from January 2016 to December 2020. Results Sixty-four patients were treated-32 in both the Sanz high and low-risk groups. In the Sanz low-risk group, 12.5% of patients received ATRA with daunorubicin and 81.25% received ATRA with ATO. In the Sanz high-risk group, 18.8% of patients received ATRA with daunorubicin, 34.3% received ATRA with daunorubicin and ATO while 40.6% received ATRA with ATO. 56.25% of patients developed differentiation syndrome. The incidence was higher in Sanz high-risk group as compared to Sanz low-risk group. 57.4% of patients had an infection at the time of presentation. 62.5% of patients developed neutropenic fever during treatment. 17.2% of patients developed pseudotumor cerebri. The 4-year EFS and OS were 71.25 and 73.13%, respectively. Sanz low-risk group had a better 4-year EFS and OS as compared to the Sanz high-risk group. Haemoglobin at presentation and Sanz high-risk group were associated with poorer outcomes with a hazard ratio of 0.8 and 3.1, respectively. Outcomes in high-risk patients were better with the use of ATRA + ATO + daunorubicin. Conclusion In the Indian population, APL patients have a high incidence of differentiation syndrome, pseudotumor cerebri, and infections during induction. CR, EFS, and OS compared to the developed world can be achieved with optimal therapy. Low haemoglobin at presentation and Sanz high-risk group were associated with poorer outcomes. ATRA, ATO, and daunorubicin combination is the preferred protocol for treating high-risk patients.

Diagnostic and therapeutic agents that target alpha-synuclein in Parkinson's disease.

The development of disease-modifying drugs and differential diagnostic agents is an urgent medical need in Parkinson’s disease. Despite the complex pathophysiological pathway, the misfolding of alpha-synuclein has been identified as a putative biomarker for detecting the onset and progression of the neurodegeneration associated with Parkinson’s disease. Identifying the most appropriate alpha-synuclein-based diagnostic modality with clinical translation will revolutionize the diagnosis of Parkinson’s. Likewise, molecules that target alpha-synuclein could alter the disease pathway that leads to Parkinson’s and may serve as first-in class therapeutics compared to existing treatment options such as levodopa and dopamine agonist that do not necessarily modify the disease pathway. Notwithstanding the promising benefits that alpha-synuclein presents to therapeutics and diagnostics development for Parkinson’s disease, finding ways to address potential challenges such as inadequate preclinical models, safety and efficacy will be paramount to achieving clinical translation. In this comprehensive review paper, we described the role of alpha-synuclein in the pathogenesis of Parkinson’s disease, as well as how its structure and function relationship delineate disease onset and progression. We further discussed different alpha-synuclein-based diagnostic modalities including biomolecular assays and molecular imaging. Finally, we presented current small molecules and biologics that are being developed as disease-modifying drugs or positron emission tomography imaging probes for Parkinson’s disease.

Cell Differentiation Agent Formulations to Win the War on Cancer

Solution of cancer was obviously an important national interest for President Nixon to declare ‘War on Cancer” in 1971. Health professionals failed the challenge to put cancer away during the 5 years of intensive presidential support and in the following 46 years of exclusive medical support allocated to cancer. Cancer stem cells (CSCs) stood in the way to deny the success of cytotoxic agents, the choice of cancer establishments in the past, to put cancer away. Cancer arises due to wound not healing properly. Consequently, the process of wound healing is the most appropriate modality of cancer therapy. Cytotoxic agents creating wounds are apparently contra-indication on cancer therapy. Cytotoxic agents are, however, the most effective agents to eliminate the most outstanding feature of cancer, namely the perpetual replication of cancer cells (CCs). A critical mechanism of wound healing is the induction of terminal differentiation of progenitor stem cells (PSCs) which are the precursors of CSCs. Wound healing metabolites active as differentiation inducers (DIs) and differentiation helper inducers (DHIs) are required to direct the terminal differentiation of PSCs to heal the wound. Cell differentiation agent (CDA) formulations are preparations of wound healing metabolites most fit to take out PSCs and CSCs by directing these cells to undergo terminal differentiation, which are protected by drug resistance and anti-apoptosis mechanisms, thus unresponsive to cytotoxic agents. CDAs alone or in combination with cytotoxic agents become perfect drugs to take out both CCs and CSCs, and to restore the functionality of chemo-surveillance necessary to win the war on cancer.

Poly-caprolactone nanofibrous coated with sol-gel alginate/ mesenchymal stem cells for cartilage tissue engineering

Human adipose-derived mesenchymal stem cells (AMSCs) were encapsulated in alginate sol and coated on PCL nanofibers to produce a scaffold. The alginate solution was generated in three different concentrations (0.5%, 2%, and 3.5%) in the specified scaffold, and the resulting solutions were ionic cross-linked to prepare coated networks on the PCL nanofibers. We analyzed the samples using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) tests. The electrospinning method and coating alginate on PCL with a calcium chloride cross-linker were both successful, according to the SEM and FTIR data. The behaviors of AMSCs in in-vitro conditions were evaluated by viability and chondrogenic potential of alginate gel through MTT, DAPI, alcian staining, and immunofluorescence (ICC) assay, respectively. The results showed that PCL/Alg scaffolds not only support the adhesion and proliferation of AMSCs but also can enhance their chondrogenic differentiation without applying any external differential agent. The cells adequately exhibited the COLLAGEN type Ⅱ expression as a chondrogenic differentiation marker. As a result, alginate gels with cells coated on PCL nanofibers have a lot of potential for building bioactive networks as a substrate in cartilage tissue engineering.

X chromosome agents of sexual differentiation.

Understanding sex differences in physiology and disease requires the identification of the molecular agents that cause phenotypic sex differences. Two groups of such agents are genes located on the sex chromosomes, and gonadal hormones. The former have coherent linkage to chromosomes that form differently in the two sexes under the influence of genomic forces that are not related to reproductive function, whereas the latter have a direct or indirect relationship to reproduction. Evidence published in the past 5 years supports the identification of several agents of sexual differentiation encoded by the X chromosome in mice, including Kdm5c, Kdm6a, Ogt and Xist. These X chromosome agents have wide pleiotropic effects, potentially influencing sex differences in many different tissues, a characteristic shared with the gonadal hormones. The identification of X chromosome agents of sexual differentiation will facilitate understanding of complex intersecting gene pathways underlying sex differences in disease.

Investigation of mechanisms underlying the inhibitory effects of metformin against proliferation and growth of neuroblastoma SH-SY5Y cells

Besides being anti-diabetic drug, metformin also has anti-proliferation and growth in several tumors; however, details of possible mechanism have not been elucidated. Here, we investigated the effects of metformin in neuroblastoma which has been termed as extra-cranial solid tumor that is due to a differentiation block with more stemness. The results showed that 5 mM metformin inhibited cell cycle progression at G0/G1 phase. Metformin also induced morphological differentiation of neuroblastoma into neuron-like phenotypes by which upregulation of MAP2, β-tubulin III and tyrosine hydroxylase expressions with no significant difference to retinoic acid (RA)-treated cells. We also tested proliferative, growth and self-renewal ability after neuroblastoma being differentiated by metformin for 24 h. The proliferative rate, sizes and numbers of colonies and spheroids were significantly reduced in differentiated neuroblastoma compared to undifferentiated neuroblastoma. A significant increase of ROS and ADP/ATP ratio with decreased mitochondrial membrane potential (MMP) were observed in metformin-treated cells, indicating mitochondrial biogenesis and metabolic change during metformin-mediated differentiation. The further studies exhibited that p-Erk1/2 and Cdk5 levels were reduced in metformin treatment whereas using PD98095 and roscovitine, selectively inhibited Erk1/2 and Cdk5, respectively, significantly increased neurite length and MAP2 expression. In addition, cell proliferation was decreased by cell cycle arrested at G0/G1 phase. Taken together, this study suggests the inhibitory effects of metformin against proliferation and growth of neuroblastoma due to induced morphological differentiation may be through Erk1/2 and Cdk5 pathways. Therefore, metformin might be eventually considered as a differentiation agent for neuroblastoma treatment in term of differentiation therapy.

Monocyte Chemotactic Protein-1 (MCP1) Accumulation in Human Osteoclast Precursor Cultures.

In vitro osteoclast methods require constant treatment with macrophage colony stimulating factor (M-CSF) to support precursor survival and addition of the differentiation agent receptor activator of NF-κB ligand (RANKL). Constant exposure to granulocyte macrophage colony stimulating factor (GM-CSF) suppresses human osteoclast formation in vitro. Addition of the chemokine monocyte chemotactic protein-1 (MCP1) to such cultures dramatically increases osteoclast formation and overcomes GM-CSF mediated suppression. We investigated the effect of M-CSF, GM-CSF and the combination of M-CSF and GM-CSF treatment on the expression of chemokines in human CD14+ cells in culture. Of assayed chemokines, MCP1 was the most abundant in terms of mRNA transcript and protein in M-CSF treated cultures and was suppressed by GM-CSF. MCP1 protein accumulated up to 50 ng/mL in culture medium, greatly exceeding other assayed chemokines. C-C chemokine receptor-2 (CCR2) is the receptor for MCP1: the formation of osteoclast-like cells was inhibited by constant exposure to the CCR2 antagonist RS102895, in part by decreasing expression of RANK, the receptor for RANKL.

Chemical Immobilization of Carboxymethyl Chitosan on Polycaprolactone Nanofibers as Osteochondral Scaffolds

Carboxymethyl chitosan (CMC) as a bio-based osteochondral inductive material was chemically immobilized on the surface of polycaprolactone (PCL) nanofibers to fabricate scaffolds for osteochondral tissue engineering applications. The chemical immobilization process included the aminolysis of ester bonds and bonding of the primary amines with glutaraldehyde as a coupling agent. The SEM and FTIR results confirmed the successfulness of the CMC immobilization. The fabricated scaffolds presented cell viabilities of > 82% and supported the attachment and proliferation of the human bone marrow mesenchymal stem cells (hBM-MSCs). The CMC-immobilized scaffolds concentration dependently induced the diverse osteochondral differentiation pathways for the hBM-MSCs without using any external differential agents. According to the Alcian Blue and Alizarin Red staining and immunocytochemistry results, scaffolds with a higher content of CMC presented more chondro-inductivity and less osteoinductivity. Thus, the CMC-immobilized scaffolds can be employed as great potential candidates for osteochondral tissue engineering applications.

PDGF-R inhibition induces glioblastoma cell differentiation via DUSP1/p38MAPK signalling.

Glioblastoma (GBM) is the most common and fatal primary brain tumour in adults. Considering that resistance to current therapies leads to limited response in patients, new therapeutic options are urgently needed. In recent years, differentiation therapy has been proposed as an alternative for GBM treatment, with the aim of bringing cancer cells into a post-mitotic/differentiated state, ultimately limiting tumour growth. As an integral component of cancer development and regulation of differentiation processes, kinases are potential targets of differentiation therapies. The present study describes how the screening of a panel of kinase inhibitors (KIs) identified PDGF-Rα/β inhibitor CP-673451 as a potential differentiation agent in GBM. We show that targeting PDGF-Rα/β with CP-673451 in vitro triggers outgrowth of neurite-like processes in GBM cell lines and GBM stem cells (GSCs), suggesting differentiation into neural-like cells, while reducing proliferation and invasion in 3D hyaluronic acid hydrogels. In addition, we report that treatment with CP-673451 improves the anti-tumour effects of temozolomide in vivo using a subcutaneous xenograft mouse model. RNA sequencing and follow-up proteomic analysis revealed that upregulation of phosphatase DUSP1 and consecutive downregulation of phosphorylated-p38MAPK can underlie the pro-differentiation effect of CP-673451 on GBM cells. Overall, the present study identifies a potential novel therapeutic option that could benefit GBM patients in the future, through differentiation of residual GSCs post-surgery, with the aim to limit recurrence and improve quality of life.

Modeling OxLDL Epigenetic Innate Immune Training of Monocytes in Early Atherosclerotic Plaques


 Atherosclerotic cardiovascular disease (atherosclerosis) is the leading cause of death worldwide. While atherogenesis is generally well understood, the sustained inflammation seen in some rapidly developing plaques remains largely unexplained. Recent research in epigenetics reports chromatin remodeling with significant pro-atherogenic effects in human monocytes exposed to oxLDL. Data collected from isolated monocytes in vitro suggests that epigenetic innate immune training may explain the observed persistent inflammatory state, however, research has yet to quantify the effects of training on early plaque dynamics. In the present study, I employ a partial differential equation and agent based mathematical model to describe key markers of atherogenesis in a system with “untrained” or “trained” monocytes. Time dependent solutions of the model suggest that innate immune training with oxLDL produces a pronounced pro-inflammatory response which has significant effects on the counts of plaque macrophages and foam cells. These results provide further support for the targeting of the epigenome in the treatment of atherosclerosis.

Bryostatin Activates CAR T-Cell Antigen-Non-Specific Killing (CTAK), and CAR-T NK-Like Killing for Pre-B ALL, While Blocking Cytolysis of a Burkitt Lymphoma Cell Line.

The advent of CAR-T cell therapy has changed the face of clinical care for relapsed and refractory pre-B-acute lymphocytic leukemia (B-ALL) and lymphoma. Although curative responses are reported, long-term cures remain below 50%. Different CAR T-cell leukemia targets appear to have different mechanisms of CAR-T escape. For CD22, therapeutic evasion is linked to down-modulation of the number CD22 proteins expressed on the extracellular aspect of the leukemia cell plasma membrane. Recently, pharmacologic agents known to induce cellular differentiation or epigenetic modification of leukemia have been shown to impact CD22 and CD19 expression levels on B-ALL, and thereby increase sensitivity to CAR-T mediated cytolysis. We explored the impact of epigenetic modifiers and differentiation agents on leukemia cell lines of B cell origin, as well as normal B cells. We confirmed the activity of bryostatin to increase CD22 expression on model cell lines. However, bryostatin does not change CD22 levels on normal B cells. Furthermore, bryostatin inhibited CAR-T mediated cytolysis of the Raji Burkitt lymphoma cell line. Bryostatin increased the cytolysis by CD22 CAR-T for B-ALL cell lines by at least three mechanisms: 1) the previously reported increase in CD22 target cell numbers on the cell surface, 2) the induction of NK ligands, and 3) the induction of ligands that sensitize leukemia cells to activated T cell antigen-non-specific killing. The opposite effect was seen for Burkitt lymphoma, which arises from a more mature B cell lineage. These findings should caution investigators against a universal application of agents shown to increase killing of leukemia target cells by CAR-T in a specific disease class, and highlights that activation of non-CAR-mediated killing by activated T cells may play a significant role in the control of disease. We have termed the killing of leukemia targets, by a set of cell-surface receptors that does not overlap with NK-like killing “CTAK,” CAR-T Cell antigen-non-specific killing.