An antibody fragment-decorated liposomal conjugate targets Philadelphia-like acute lymphoblastic leukemia.

Philadelphia-like acute lymphoblastic leukemia (Ph-like ALL) is an aggressive B-ALL malignancy associated with high rates of relapse and inferior survival rate. While targeted treatments against the cell surface proteins CD22 or CD19 have been transformative in the treatment of refractory B-ALL, patients may relapse due to antigen loss, necessitating targeting alternative antigens. Cytokine receptor-like factor 2 (CRLF2) is overexpressed in half of Ph-like ALL cases conferring chemoresistance and enhancement of leukemia cell survival. Therefore, targeting CRLF2 may reduce the likelihood of relapse associated with antigen loss. We developed a CRLF2-targeting single-chain variable fragment modified by the fragment crystallizable region (CRLF2 scFv-Fc) conjugated to a drug maytansinoid 1 (DM1)-DOPC liposomal conjugate, creating homogeneous CRLF2-targeted liposomes (CRLF2-DM1 LIP). Cellular association and internalization studies in a Ph-like ALL cell line, MHH-CALL-4, compared to its lentivirally transduced CRLF2-knockdown counterpart (KD-CALL-4) revealed excellent CRLF2-targeting efficiency of CRLF2-DM1 LIP. Moreover, CRLF2-DM1 LIP showed selective association and internalization ex vivo using Ph-like ALL patient-derived xenograft (PDX) cells with minimal reactivity with non-target cells. Cell apoptosis assays demonstrated the CRLF2-dependent potency of CRLF2-DM1 LIP in Ph-like ALL cell lines. This study is the first to highlight the therapeutic potential of a CRLF2-directed scFv-Fc-liposomal conjugate for targeting Ph-like ALL.

Radiographic texture analysis of the hard tissue changes following socket preservation with allograft and xenograft materials for dental implantation: a randomized clinical trial.

OBJECTIVES: This study aimed to assess the hard tissue changes following socket preservation with allograft and xenograft materials for dental implantation by texture analysis (TA) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This prospective clinical trial was conducted on 25 patients who required the extraction of carious mandibular posterior teeth and their subsequent replacement with dental implants. The patients were categorized into three groups: (I) no socket preservation, (II) socket preservation with xenograft material, and (III) socket preservation with allograft material. Four months after tooth extraction, the patients were recalled for preoperative assessment before dental implantation, and CBCT scans were obtained (Kvp:110, mA:1.94, S:3.6). MaZda software was used to compare homogeneity, contrast, and texture complexity on axial CBCT sections among the three groups. RESULTS: Significant differences existed among the three groups in all parameters (P < 0.05) except for the mean correlation parameter (P > 0.05). The results showed no significant difference between the no graft and xenograft groups regarding contrast and differential (dif.) entropy (P > 0.05). Also, no significant difference was found between the xenograft and allograft groups regarding the dif. variance and also between the no graft and allograft groups regarding the inverse difference moment(InvDfMom) and dif. variance parameters (P > 0.05). All other pairwise comparisons revealed significant differences (P < 0.05). CONCLUSION: TA can be used for the quantification of radiographic changes of bone following socket preservation and potentially accelerate the process of decision-making for dental implant treatment.

Circulating Tumor DNA in Pediatric Cancer.

The measurement of circulating tumor DNA (ctDNA) has gained increasing prominence as a minimally invasive tool for the detection of cancer-specific markers in plasma. In adult cancers, ctDNA detection has shown value for disease-monitoring applications including tumor mutation profiling, risk stratification, relapse prediction, and treatment response evaluation. To date, there are ctDNA tests used as companion diagnostics for adult cancers and it is not understood why the same cannot be said about childhood cancer, despite the marked differences between adult and pediatric oncology. In this review, we discuss the current understanding of ctDNA as a disease monitoring biomarker in the context of pediatric malignancies, including the challenges associated with ctDNA detection in liquid biopsies. The data and conclusions from pediatric cancer studies of ctDNA are summarized, highlighting treatment response, disease monitoring and the detection of subclonal disease as applications of ctDNA. While the data from retrospective studies highlight the potential of ctDNA, large clinical trials are required for ctDNA analysis for routine clinical use in pediatric cancers. We outline the requirements for the standardization of ctDNA detection in pediatric cancers, including sample handling and reproducibility of results. With better understanding of the advantages and limitations of ctDNA and improved detection methods, ctDNA analysis may become the standard of care for patient monitoring in childhood cancers.

The Incidence of Aphasia, Cognitive Deficits, Apraxia, Dysarthria, and Dysphagia in Acute Post Stroke Persian Speaking Adults.

Stroke is a major cause of serious disabilities in adults. While communication deficits post stroke are prevalent and disabling, early detection of them is important during acute phase. There is limited data published on the incidence of communication disorders in Persian speaking adults following post stroke to our knowledge. The present study aims to determine the incidence and associated factors of aphasia, cognitive deficits, motor speech disorders (apraxia and dysarthria) as well as dysphagia following acute post stroke in Persian speaking adults. 100 stroke patients were assessed using P-WAB, MMSE, Oral Apraxia test, Informal Dysarthria assessment, and MASA. The data was collected from 2 hospitals in Tehran using convenient sampling for the duration of 1 year. Based on our findings, the incidence of aphasia, cognitive deficits, oral apraxia, dysarthria, and dysphagia was in respectively 61.8%, 76%, 30%, 61%, and 39% of stroke patients during the acute phase. Patients with aphasia were significantly older (mean age, 59.29 vs. 64.95), and had fewer education years (9.21 vs. 5.45) compared to individuals without aphasia (p < .05). Co-occurrence of aphasia and dysarthria, dysphasia, cognitive deficits, and apraxia was in respectively 40%, 31%, 55%, and 25%. Due to the high incidence of neurogenic communication disorders and dysphagia during the acute post stroke, especially in the elderly and the less educated patients, prompt and rapid detection of these deficits and rehabilitation is essential to ameliorate patients' quality of life and social participation, and reduce the comorbidities risk.

A recombinant antibody fragment directed to the thymic stromal lymphopoietin receptor (CRLF2) efficiently targets pediatric Philadelphia chromosome-like acute lymphoblastic leukemia.

Antibody fragments are promising building blocks for developing targeted therapeutics, thus improving treatment efficacy while minimising off-target toxicity. Despite recent advances in targeted therapeutics, patients with Philadelphia-like acute lymphoblastic leukemia (Ph-like ALL), a high-risk malignancy, lack specific and effective targeted treatments. Cytokine receptor-like factor 2 (CRLF2) is overexpressed in 50% of Ph-like ALL cases, conferring the survival of leukemia blasts through activation of the JAK/STAT signalling pathway. Targeting such a vital cell-surface protein could result in potent anti-leukaemic efficacy and reduce the likelihood of relapse associated with antigen loss. Herein, we developed a novel single-chain variable fragment (scFv) against CRLF2 based on a monoclonal antibody raised against the recombinant extracellular domain of human TSLPRα chain. The scFv fragment demonstrated excellent binding affinity with CRLF2 protein in the nanomolar range. Cellular association studies in vitro using an inducible CRLF2 knockdown cell line and ex vivo using patient-derived xenografts revealed the selective association of the scFv with CRLF2. The fragment exhibited significant receptor antagonistic effects on STAT5 signalling, suggesting possible therapeutic implications in vivo. This study is the first to describe the potential use of a novel scFv for targeting Ph-like ALL.

Thiol-Reactive Star Polymers Functionalized with Short Ethoxy-Containing Moieties Exhibit Enhanced Uptake in Acute Lymphoblastic Leukemia Cells.

PURPOSE: Directing nanoparticles to cancer cells without using antibodies is of great interest. Subtle changes to the surface chemistry of nanoparticles can significantly affect their biological fate, including their propensity to associate with different cell populations. For instance, nanoparticles functionalized with thiol-reactive groups can potentially enhance association with cells that over-express cell-surface thiol groups. The potential of such an approach for enhancing drug delivery for childhood acute lymphoblastic leukemia (ALL) cells has not been investigated. Herein, we investigate the impact of thiol-reactive star polymers on the cellular association and the mechanisms of uptake of the nanoparticles. METHODS: We prepared fluorescently labeled star polymers functionalized with an mPEG brush corona and pyridyl disulfide to examine how reactivity to exofacial thiols impacts cellular association with ALL cells. We also studied how variations to the mPEG brush composition could potentially be used as a secondary method for controlling the extent of cell association. Specifically, we examined how the inclusion of shorter diethylene glycol brush moieties into the nanoparticle corona could be used to further influence cell association. RESULTS: Star polymers incorporating both thiol-reactive and diethylene glycol brush moieties exhibited the highest cellular association, followed by those functionalized solely with thiol reactive groups compared to control nanoparticles in T and B pediatric ALL patient-derived xenografts harvested from the spleens and bone marrow of immunodeficient mice. Transfection of cells with an early endosomal marker and imaging with correlative light and electron microscopy confirmed cellular uptake. Endocytosis inhibitors revealed dynamin-dependent clathrin-mediated endocytosis as the main uptake pathway for all the star polymers. CONCLUSION: Thiol-reactive star polymers having an mPEG brush corona that includes a proportion of diethylene glycol brush moieties represent a potential strategy for improved leukemia cell delivery.

Dose-dependent autophagic effect of titanium dioxide nanoparticles in human HaCaT cells at non-cytotoxic levels.

BACKGROUND: Interactions between nanoparticles and cells are now the focus of a fast-growing area of research. Though many nanoparticles interact with cells without any acute toxic responses, metal oxide nanoparticles including those composed of titanium dioxide (TiO2-NPs) may disrupt the intracellular process of macroautophagy. Autophagy plays a key role in human health and disease, particularly in cancer and neurodegenerative diseases. We herein investigated the in vitro biological effects of TiO2-NPs (18 nm) on autophagy in human keratinocytes (HaCaT) cells at non-cytotoxic levels. RESULTS: TiO2-NPs were characterized by transmission electron microscopy (TEM) and dynamic light scattering techniques. Cellular uptake, as evaluated by TEM and NanoSIMS revealed that NPs internalization led to the formation of autophagosomes. TiO2-NPs treatment did not reduce cell viability of HaCaT cells nor increased oxidative stress. Cellular autophagy was additionally evaluated by confocal microscopy using eGFP-LC3 keratinocytes, western blotting of autophagy marker LC3I/II, immunodetection of p62 and NBR1 proteins, and gene expression of LC3II, p62, NBR1, beclin1 and ATG5 by RT-qPCR. We also confirmed the formation and accumulation of autophagosomes in NPs treated cells with LC3-II upregulation. Based on the lack of degradation of p62 and NBR1 proteins, autophagosomes accumulation at a high dose (25.0 µg/ml) is due to blockage while a low dose (0.16 µg/ml) promoted autophagy. Cellular viability was not affected in either case. CONCLUSIONS: The uptake of TiO2-NPs led to a dose-dependent increase in autophagic effect under non-cytotoxic conditions. Our results suggest dose-dependent autophagic effect over time as a cellular response to TiO2-NPs. Most importantly, these findings suggest that simple toxicity data are not enough to understand the full impact of TiO2-NPs and their effects on cellular pathways or function.