Longitudinal intravital imaging of mouse placenta.

Studying placental functions is crucial for understanding pregnancy complications. However, imaging placenta is challenging due to its depth, volume, and motion distortions. In this study, we have developed an implantable placenta window in mice that enables high-resolution photoacoustic and fluorescence imaging of placental development throughout the pregnancy. The placenta window exhibits excellent transparency for light and sound. By combining the placenta window with ultrafast functional photoacoustic microscopy, we were able to investigate the placental development during the entire mouse pregnancy, providing unprecedented spatiotemporal details. Consequently, we examined the acute responses of the placenta to alcohol consumption and cardiac arrest, as well as chronic abnormalities in an inflammation model. We have also observed viral gene delivery at the single-cell level and chemical diffusion through the placenta by using fluorescence imaging. Our results demonstrate that intravital imaging through the placenta window can be a powerful tool for studying placenta functions and understanding the placental origins of adverse pregnancy outcomes.

Chromatin Remodeling in Patient-Derived Colorectal Cancer Models.

Patient-Derived Organoids (PDO) and Xenografts (PDX) are the current gold standards for patient-derived models of cancer (PDMC). Nevertheless, how patient tumor cells evolve in these models and the impact on drug response remains unclear. Herein, the transcriptomic and chromatin accessibility landscapes of matched colorectal cancer (CRC) PDO, PDX, PDO-derived PDX (PDOX), and original patient tumors (PT) are compared. Two major remodeling axes are discovered. The first axis delineates PDMC from PT, and the second axis distinguishes PDX and PDO. PDOX are more similar to PDX than PDO, indicating the growth environment is a driving force for chromatin adaptation. Transcription factors (TF) that differentially bind to open chromatins between matched PDO and PDOX are identified. Among them, KLF14 and EGR2 footprints are enriched in PDOX relative to matched PDO, and silencing of KLF14 or EGR2 promoted tumor growth. Furthermore, EPHA4, a shared downstream target gene of KLF14 and EGR2, altered tumor sensitivity to MEK inhibitor treatment. Altogether, patient-derived CRC cells undergo both common and distinct chromatin remodeling in PDO and PDX/PDOX, driven largely by their respective microenvironments, which results in differences in growth and drug sensitivity and needs to be taken into consideration when interpreting their ability to predict clinical outcome.

Waldenström Macroglobulinemia/Lymphoplasmacytic Lymphoma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

The treatment of Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) has evolved to include several new options. The NCCN Guidelines for WM/LPL provide a framework on which to base decisions regarding diagnosis, treatment, assessment of response to treatment, and follow-up of both newly diagnosed and previously treated WM/LPL.

Multiple Myeloma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

The treatment of relapsed/refractory multiple myeloma (MM) has evolved to include several new options. These include new combinations with second generation proteasome inhibitors (PI); second generation immunomodulators, monoclonal antibodies, CAR T cells, bispecific antibodies, selinexor, venetoclax, and many others. Most patients with MM undergo several cycles of remissions and relapse, and therefore need multiple lines of combination therapies. Selecting treatment options for relapsed/refractory MM requires consideration of resistance status to specific classes, and patient-specific factors such as age and other comorbidities should be considered. The NCCN Guidelines for MM provide a framework on which to base decisions regarding workup, treatment, and follow-up of newly diagnosed and previously treated MM. This manuscript outlines the recommendations from NCCN Guidelines for MM specific to relapsed/refractory disease.

Gate-controlled Sb2S3 thin film photodetectors for logic switches.

Antimony sulfide (Sb2S3) photodetectors (PDs) have great potential in commercial applications. The performances are affected by photocarrier distribution and recombination. Here, the gate-controlled Sb2S3 thin film PD is fabricated on the TiO2/SiO2/Si substrate by the vacuum method. The p-channel Sb2S3 transistor obtained a threshold voltage of 0.6 V and a switching ratio of 1064, achieving an effective regulation by gate voltages. A negative gate voltage can enhance conductivity and can suppress recombination. The responsivity and detectivity of the PD reach 1.6 A/W and 1.2 × 1011 Jones, respectively. The device realizes logic outputs by the signal inputs of illumination and gate voltage.

SLAMF7 as a Promising Immunotherapeutic Target in Multiple Myeloma Treatments.

Multiple myeloma (MM) is a common hematological malignancy that has fostered several new therapeutic approaches to combat newly diagnosed or relapsed MM. While the field has advanced over the past 2 decades, the majority of patients will develop resistance to these treatments, causing the need for new therapeutic targets. SLAMF7 is an attractive therapeutic target in multiple myeloma, and a monoclonal antibody that targets SLAMF7 has shown consistent beneficial outcomes in clinical trials to date. In this review, we will focus on the structure and regulation of SLAMF7 and its mechanism of action. The most recent clinical trials will be reviewed to further understand the clinical implications and improve the prognosis of MM. Furthermore, the efficacy of anti-SLAMF7 monoclonal antibodies combined with standard therapies and possible resistance mechanisms will be discussed. This review aimed to provide a detailed summary of the role of SLAMF7 in the pathogenesis of patients with MM and the rationale for further investigation into SLAMF7-mediated molecular pathways associated with MM development.

RXR Agonists Enhance Lenalidomide Anti-Myeloma Activity and T Cell Functions while Retaining Glucose-Lowering Effect.

Retinoid X receptor (RXR) heterodimerizes with the PPAR nuclear hormone receptor and regulates its downstream events. We investigated the effects of RXR agonists (LG100754, bexarotene, AGN194204, and LG101506) on lenalidomide's anti-myeloma activity, T cell functions, and the level of glucose and lipids in vivo. Genetic overexpression and CRISPR/Cas9 knockout experiments were conducted in multiple myeloma (MM) cell lines and Jurkat T cell lines to determine the roles of CRBN in RXR-agonist mediated effects. A xenograft mouse model of MM was established to determine the combination effect of LG100754 and lenalidomide. The combination of RXR agonists and lenalidomide demonstrated synergistic activity in increasing CRBN expression and killing myeloma cells. Mechanistically, the RXR agonists reduced the binding of PPARs to the CRBN promoter, thereby relieving the repressor effect of PPARs on CRBN transcription. RXR agonists downregulated the exhaustion markers and increased the activation markers of Jurkat T cells and primary human T cells. Co-administration of LG100754 and lenalidomide showed enhanced anti-tumor activity in vivo. LG100754 retained its glucose- and lipid-lowering effects. RXR agonists demonstrate potential utility in enhancing drug sensitivity and T-cell function in the treatment of myeloma.

Inhibition of Sphingosine Kinase 2 Results in PARK2-Mediated Mitophagy and Induces Apoptosis in Multiple Myeloma.

Mitophagy plays an important role in maintaining mitochondrial homeostasis by clearing damaged mitochondria. Sphingosine kinase 2 (SK2), a type of sphingosine kinase, is an important metabolic enzyme involved in generating sphingosine-1-phosphate. Its expression level is elevated in many cancers and is associated with poor clinical outcomes. However, the relationship between SK2 and mitochondrial dysfunction remains unclear. We found that the genetic downregulation of SK2 or treatment with ABC294640, a specific inhibitor of SK2, induced mitophagy and apoptosis in multiple myeloma cell lines. We showed that mitophagy correlates with apoptosis induction and likely occurs through the SET/PP2AC/PARK2 pathway, where inhibiting PP2AC activity may rescue this process. Furthermore, we found that PP2AC and PARK2 form a complex, suggesting that they might regulate mitophagy through protein-protein interactions. Our study demonstrates the important role of SK2 in regulating mitophagy and provides new insights into the mechanism of mitophagy in multiple myeloma.

Systemic Light Chain Amyloidosis, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology.

Primary systemic light chain amyloidosis (SLCA) is characterized by production of light chains that get converted to amyloid fibrils with an affinity for visceral organs and causing organ dysfunction. The therapy for SLCA is directed to recovering the function of the affected organs by targeting the abnormal plasma cell clone and slowing deposition of amyloid fibrils. The NCCN Guidelines for SLCA provide recommendations for workup, diagnosis, and treatment of primary as well as previously treated SLCA.

Controlling the morphology and wavelength of self-assembled coaxial GaAs/Ga(As)Sb/GaAs single quantum-well nanowires.

Antimonide-based ternary III-V nanowires (NWs) provide a tunable bandgap over a wide range, and the GaAsSb material system has prospective applications in the 1.3-1.55 µm spectral range of optical communications. In this paper, GaAs/Ga(As)Sb/GaAs single quantum well (SQW) NWs were grown on Si(111) substrates by molecular beam epitaxy (MBE). In addition, the morphologies and tunable wavelengths of the GaAs/Ga(As)Sb/GaAs SQWs were adjusted by interrupting the Ga droplets and changing the growth temperatures and V/III ratios. The four morphologies of the GaAs/Ga(As)Sb/GaAs SQW NWs were observed by scanning electron microscopy (SEM). The microscale lattice structure related to the incorporation of Sb in GaAs/Ga(As)Sb/GaAs SQWs was studied by Raman spectroscopy. The crystal quality of the GaAs/Ga(As)Sb/GaAs SQW NWs was researched by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the optical properties of the GaAs/Ga(As)Sb/GaAs SQWs were investigated by photoluminescence (PL) spectroscopy. The PL spectra showed the peak emission wavelength range of ∼818 nm (GaAs) to ∼1628 nm (GaSb) at 10 K. This study provides an approach to enhance the effective control of the morphology, structure and wavelength of quantum well or core-shell NWs.

A Phase I Trial of SYK Inhibition with Fostamatinib in the Prevention and Treatment of Chronic Graft-Versus-Host Disease.

Despite the exciting advancement of novel therapies, chronic graft-versus-host disease (cGVHD) remains the most common cause of non-relapse mortality after allogeneic hematopoietic stem cell transplantation (HCT). Frontline treatment of cGVHD involves systemic steroids, which are associated with significant morbidities. We previously found that inhibition of spleen tyrosine kinase (SYK) with fostamatinib preferentially eradicated aberrantly activated B cells in both ex vivo studies of cGVHD patient B cells, as well as in vivo mouse studies. These and other preclinical studies implicated hyper-reactive B-cell receptor signaling and increased SYK expression in the pathogenesis of cGVHD and compelled this first in-human allogeneic HCT clinical trial. We investigated the safety and efficacy of the oral SYK inhibitor, fostamatinib, for both the prevention and treatment of cGVHD. The primary objective was to evaluate the safety of fostamatinib and determine its maximum tolerated dose in the post-HCT setting. Secondary objectives included assessing the efficacy of fostamatinib in preventing and treating cGVHD, as well as examining alterations in B-cell compartments with treatment. This was a single-institution phase I clinical trial that evaluated the use of fostamatinib in allogeneic HCT patients before the development of cGVHD or at the time of steroid-refractory cGVHD (SR-cGVHD). Patients received fostamatinib at one of three dose levels using a continual reassessment algorithm to determine the maximum tolerated dose. Multiparameter flow cytometry was used to evaluate changes in B cell subpopulations over the first year of treatment with fostamatinib. Nineteen patients were enrolled in this phase I trial, with 5 in the prophylaxis arm and 14 in the therapeutic arm. One patient (5%) required discontinuation of therapy for a dose-limiting toxicity. At a median follow-up of over 3 years, no patients had cancer relapse while on fostamatinib treatment, and recurrent malignancy was observed in 1 patient 2 years after the end of therapy. In the prophylaxis arm, 1 of 5 patients (20%) developed cGVHD while on fostamatinib. In the therapeutic arm, the overall response rate was 77%, with a complete response rate of 31%. The median duration of response was 19.3 months and the 12-month failure-free survival was 69% (95% confidence interval, 48-100). Patients were able to reduce their steroid dose by a median of 80%, with 73% remaining on a lower dose at 1 year compared to baseline. There was an early reduction in the proportion of IgD-CD38hi plasmablast-like cells with fostamatinib treatment, particularly in those SR-cGVHD patients who had an eventual response. B-cell reconstitution was not significantly impacted by fostamatinib therapy after allogeneic HCT. Fostamatinib featured a favorable safety profile in the post-HCT setting. Our data suggests an early efficacy signal that was associated with effects on expected cell targets in both the prophylaxis and treatment of cGVHD, providing rationale for a phase II investigation.

Phase I study of opaganib, an oral sphingosine kinase 2-specific inhibitor, in relapsed and/or refractory multiple myeloma.

Multiple myeloma (MM) remains an incurable disease and there is an unmet medical need for novel therapeutic drugs that do not share similar mechanisms of action with currently available agents. Sphingosine kinase 2 (SK2) is an innovative molecular target for anticancer therapy. We previously reported that treatment with SK2 inhibitor opaganib inhibited myeloma tumor growth in vitro and in vivo in a mouse xenograft model. In the current study, we performed a phase I study of opaganib in patients with relapsed/refractory multiple myeloma (RRMM). Thirteen patients with RRMM previously treated with immunomodulatory agents and proteasome inhibitors were enrolled and treated with single-agent opaganib at three oral dosing regimens (250 mg BID, 500 mg BID, or 750 mg BID, 28 days as a cycle). Safety and maximal tolerated dose (MTD) were determined. Pharmacokinetics, pharmacodynamics, and correlative studies were also performed. Opaganib was well tolerated up to a dose of 750 mg BID. The most common possibly related adverse event (AE) was decreased neutrophil counts. There were no serious AEs considered to be related to opaganib. MTD was determined as at least 750 mg BID. On an intent-to-treat basis, one patient (7.7%) in the 500 mg BID dose cohort showed a very good partial response, and one other patient (7.7%) achieved stable disease for 3 months. SK2 is an innovative molecular target for antimyeloma therapy. The first-in-class SK2 inhibitor opaganib is generally safe for administration to RRMM patients, and has potential therapeutic activity in these patients. Clinicaltrials.gov: NCT02757326.

Thioredoxin-1 regulates self-renewal and differentiation of murine hematopoietic stem cells through p53 tumor suppressor.

BACKGROUND: Thioredoxin-1 (TXN1) is one of the major cellular antioxidants in mammals and is involved in a wide range of physiological cellular responses. However, little is known about the roles and the underlying molecular mechanisms of TXN1 in the regulation of hematopoietic stem/progenitor cells (HSPCs). METHODS: TXN1 conditional knockout mice (ROSA-CreER-TXN1fl/fl) and TXN1fl/fl control mice were used. The mice were treated with tamoxifen and the number and biological functions of HSPCs were measured by flow cytometry, PCR and western blot. Limiting dilution competitive transplantation with sorted HSCs and serial transplantations were performed to assess the effects of TXN1 knockout on HSC self-renewal and long-term reconstitutional capacity. RNA sequencing (RNA-seq) was performed to investigate the downstream molecular pathways of TXN1 deletion in murine HSPCs. CRISPR/Cas9 knockout experiments were performed in vitro in EML murine hematopoietic stem/progenitor cell line to investigate the effects of TXN1 and/or TP53 deletion on cell survival, senescence and colony forming units. TP53 protein degradation assay, CHiP PCR and PGL3 firefly/renilla reporter assay were performed. The effects of TXN1 on various molecular pathways relevant to HSC radiation protection were examined in vitro and in vivo. RESULTS: TXN1-TP53 tumor suppressor axis regulates HSPC biological fitness. Deletion of TXN1 in HSPCs using in vivo and in vitro models activates TP53 signaling pathway, and attenuates HSPC capacity to reconstitute hematopoiesis. Furthermore, we found that knocking out of TXN1 renders HSPCs more sensitive to radiation and treatment with recombinant TXN1 promotes the proliferation and expansion of HSPCs. CONCLUSIONS: Our findings suggest that TXN1-TP53 axis acts as a regulatory mechanism in HSPC biological functions. Additionally, our study demonstrates the clinical potential of TXN1 for enhancing hematopoietic recovery in hematopoietic stem cell transplant and protecting HSPCs from radiation injury.

An autologous humanized patient-derived xenograft (PDX) model for evaluation of nivolumab immunotherapy in renal cell cancer: a case report.

Background: There is an unmet need for developing faithful animal models for preclinical evaluation of immunotherapy. The current approach to generate preclinical models for immunotherapy evaluation has been to transplant CD34+ cells from umbilical cord blood into immune-deficient mice followed by implantation of patient derived tumor cells. However, current models are associated with high tumor rejection rate secondary to the allograft vs. tumor response from human leukocyte antigen (HLA) mismatches. We herein report the first development of a novel, humanized patient-derived xenograft (PDX) model using autologous CD34+ cells from bone marrow aspirate obtained from a patient with metastatic clear cell renal cell carcinoma (mRCC) from whom a PDX had been developed. Case Description: This is a 68-year-old Caucasian man diagnosed with mRCC with metastasis to the liver in 2014. He was treated with sunitinib +/- AGS-003 and underwent a cytoreductive right nephrectomy, left adrenalectomy and partial liver resection. PDX was generated using resected nephrectomy specimen. After surgery, patient received multiple lines of standard of care therapy including sunitinib, axitinib, bevacizumab, everolimus and cabozantinib. While progressing on cabozantinib, he was treated with nivolumab. Seven years after initiation of nivolumab, and 4 years after stopping systemic therapy, he remains in complete remission. To generate autologous PDX model, bone marrow aspirate was performed and CD34+ hematopoietic stem/progenitor cells (HSPCs) were isolated and injected into 150 rad irradiated non-obese diabetic scid gamma null (NSG) mice. At 11 weeks post-transplant, the matched patient PDX was injected subcutaneously into the humanized mice and the mice were treated with nivolumab. Conclusions: Our case represents successful therapy of nivolumab in mRCC. Furthermore, HPSCs obtained from a single bone marrow aspirate were able to reconstitute an immune system in the mice that allowed nivolumab to inhibit the tumor growth of PDX and recapitulated the durable remission observed in the patient with nivolumab. We observed the reconstitution of human T cells, B cells and natural killer (NK) cells and unlike the humanized mouse model using cord blood, our model system eliminates the tumor rejection from mis-matched HLA. Our autologous humanized renal cell carcinoma (RCC) PDX model provides an effective tool to study immunotherapy in a preclinical setting.

Mechanistic Studies and a Retrospective Cohort Study: The Interaction between PPAR Agonists and Immunomodulatory Agents in Multiple Myeloma.

Our previous study demonstrated that peroxisome proliferator-activated receptor (PPAR) agonists downregulated cereblon (CRBN) expression and reduced the anti-myeloma activity of lenalidomide in vitro and in vivo. We aimed to determine whether DNA methylation and protein degradation contribute to the effects of PPAR agonists. CRBN promoter methylation status was detected using methylation-specific polymerase chain reaction. The CRBN protein degradation rate was measured using a cycloheximide chase assay. Metabolomic analysis was performed in multiple myeloma (MM) cells treated with PPAR agonists and/or lenalidomide. Our retrospective study determined the effect of co-administration of PPAR agonists with immunomodulatory drugs on the outcomes of patients with MM. CpG islands of the CRBN promoter region became highly methylated upon treatment with PPAR agonists, whereas treatment with PPAR antagonists resulted in unmethylation. The CRBN protein was rapidly degraded after treatment with PPAR agonists. Lenalidomide and fenofibrate showed opposite effects on acylcarnitines and amino acids. Co-administration of immunomodulatory drugs and PPAR agonists was associated with inferior treatment responses and poor survival. Our study provides the first evidence that PPAR agonists reduce CRBN expression through various mechanisms including inducing methylation of CRBN promoter CpG island, enhancing CRBN protein degradation, and affecting metabolomics of MM cells.

Emerging Evidence of the Significance of Thioredoxin-1 in Hematopoietic Stem Cell Aging.

The United States is undergoing a demographic shift towards an older population with profound economic, social, and healthcare implications. The number of Americans aged 65 and older will reach 80 million by 2040. The shift will be even more dramatic in the extremes of age, with a projected 400% increase in the population over 85 years old in the next two decades. Understanding the molecular and cellular mechanisms of ageing is crucial to reduce ageing-associated disease and to improve the quality of life for the elderly. In this review, we summarized the changes associated with the ageing of hematopoietic stem cells (HSCs) and what is known about some of the key underlying cellular and molecular pathways. We focus here on the effects of reactive oxygen species and the thioredoxin redox homeostasis system on ageing biology in HSCs and the HSC microenvironment. We present additional data from our lab demonstrating the key role of thioredoxin-1 in regulating HSC ageing.

PPAR agonists attenuate lenalidomide's anti-myeloma activity in vitro and in vivo.

Many patients with multiple myeloma (MM) have comorbidities and are treated with PPAR agonists. Immunomodulatory agents (IMiDs) are the cornerstones for MM therapy. Currently, little is known about how co-administration of PPAR agonists impacts lenalidomide treatment in patients with MM. Here, we determined the effects of PPAR agonists on anti-myeloma activities of lenalidomide in vitro and in a myeloma xenograft mouse model. Genetic overexpression and CRISPR/cas9 knockout experiments were performed to determine the role of CRBN in the PPAR-mediated pathway. A retrospective cohort study was performed to determine the correlation of PPAR expression with the outcomes of patients with MM. PPAR agonists down-regulated CRBN expression and reduced the anti-myeloma efficacy of lenalidomide in vitro and in vivo. Co-treatment with PPAR antagonists increased CRBN expression and improved sensitivity to lenalidomide. PPAR expression was higher in bone marrow cells of patients with newly diagnosed MM than in normal control bone marrow samples. High PPAR expression was correlated with poor clinical outcomes. Our study provides the first evidence that PPARs transcriptionally regulate CRBN and that drug-drug interactions between PPAR agonists and IMiDs may impact myeloma treatment outcomes.

Dual functions of microRNA-17 in maintaining cartilage homeostasis and protection against osteoarthritis.

Damaged hyaline cartilage has no capacity for self-healing, making osteoarthritis (OA) "difficult-to-treat". Cartilage destruction is central to OA patho-etiology and is mediated by matrix degrading enzymes. Here we report decreased expression of miR-17 in osteoarthritic chondrocytes and its deficiency contributes to OA progression. Supplementation of exogenous miR-17 or its endogenous induction by growth differentiation factor 5, effectively prevented OA by simultaneously targeting pathological catabolic factors including matrix metallopeptidase-3/13 (MMP3/13), aggrecanase-2 (ADAMTS5), and nitric oxide synthase-2 (NOS2). Single-cell RNA sequencing of hyaline cartilage revealed two distinct superficial chondrocyte populations (C1/C2). C1 expressed physiological catabolic factors including MMP2, and C2 carries synovial features, together with C3 in the middle zone. MiR-17 is highly expressed in both superficial and middle chondrocytes under physiological conditions, and maintains the physiological catabolic and anabolic balance potentially by restricting HIF-1α signaling. Together, this study identified dual functions of miR-17 in maintaining cartilage homeostasis and prevention of OA.

A thermo-sensitive and injectable hydrogel derived from a decellularized amniotic membrane to prevent intrauterine adhesion by accelerating endometrium regeneration.

Objective To investigate the effect of the injectable hydrogel generated from a decellularized amniotic membrane (dAM)-gel on preventing the development of an intrauterine adhesion (IUA) on a rat model. Methods The dAM-gel was developed from an amniotic membrane (AM) by a process of decellularization, lyophilization, and enzyme digestion. Histological analysis, residual component determination, electronic microscopy and turbidimetric gelation kinetics analysis were performed to characterize the dAM-gel. The proliferation and migration of endometrial cells on the dAM-gel coated surface was examined. IUA was surgically created in rats and received dAM-gel injection immediately after wound creation. Gene profiles of epithelial cells cultured on the dAM-gel coated surface were evaluated by RNA-sequencing. Results The collagen content was retained in the dAM-gel, while the GAG content decreased significantly compared with fresh AM (fAM). Gelation of the gel was temperature-sensitive and showed a matrix concentration-dependent manner. Transplantation of the dAM-gel significantly reduced fibrosis of IUA with a recovered uterine cavity, regenerated endometrium and increased microvascular density, along with elevated pregnancy rate compared with endometrium damage groups. Migration of epithelial cells was greatly promoted by the dAM-gel in a surgically created uterine wound model. By comparing the RNA-sequence data of epithelial cells that were cultured on dAM-gel coated and non-coated surfaces, respectively, distinct gene profiles relative to the cellular migration, adhesion and angiogenesis and involved signaling pathway were identified. Conclusions The injectable dAM-gel developed from AM offers a promising option for preventing endometrial fibrosis by promotion of the re-epithelialization of the damaged endometrium.