Raji Cells Research Articles

Doxorubicin-conjugated siRNA lipid nanoparticles for combination cancer therapy.

Evasion of apoptosis is a hallmark of cancer, attributed in part to overexpression of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2). In a variety of cancer types, including lymphoma, Bcl-2 is overexpressed. Therapeutic targeting of Bcl-2 has demonstrated efficacy in the clinic and is the subject of extensive clinical testing in combination with chemotherapy. Therefore, the development of co-delivery systems for Bcl-2 targeting agents, such as small interfering RNA (siRNA), and chemotherapeutics, such as doxorubicin (DOX), holds promise for enabling combination cancer therapies. Lipid nanoparticles (LNPs) are a clinically advanced nucleic acid delivery system with a compact structure suitable for siRNA encapsulation and delivery. Inspired by ongoing clinical trials of albumin-hitchhiking doxorubicin prodrugs, here we developed a DOX-siRNA co-delivery strategy via conjugation of doxorubicin to the surface of siRNA-loaded LNPs. Our optimized LNPs enabled potent knockdown of Bcl-2 and efficient delivery of DOX into the nucleus of Burkitts' lymphoma (Raji) cells, leading to effective inhibition of tumor growth in a mouse model of lymphoma. Based on these results, our LNPs may provide a platform for the co-delivery of various nucleic acids and DOX for the development of new combination cancer therapies.

Identification and Biological Evaluation of a Water-Soluble Fullerene Nanomaterial as BTK Kinase Inhibitor.

Thanks to recent advances in synthetic methodology, water-soluble fullerene nanomaterials that interfere with biomolecules, especially DNA/RNA and selected proteins, have been found with tremendous potential for applications in nanomedicine. Herein, we describe the synthesis and evaluation of a water-soluble glycine-derived [60]fullerene hexakisadduct (HDGF) with T h symmetry, which is a first-in-class BTK protein inhibitor. We synthesized and characterized glycine derived [60]fullerene using NMR, ESI-MS, and ATR-FT-IR. DLS and zeta potential were measured and high-resolution transmission electron microscopy (HRTEM) observations were performed. The chemical composition of the water-soluble fullerene nanomaterial was examined by X-ray photoelectron spectrometry. To observe aggregate formation, the cryo-TEM analysis was carried out. The docking studies and molecular dynamic simulations were performed to determine interactions between HDGF and BTK. The in vitro cytotoxicity was evaluated on RAJI and K562 blood cancer cell lines. Subsequently, we examined the induction of cell death by autophagy and apoptosis by determining the expression levels of crucial genes and caspases. We investigated the direct association of HDGF on inhibition of the BTK signalling pathway by examining changes in the calcium levels in RAJI cells after treatment. The inhibitory potential of HDGF against non-receptor tyrosine kinases was evaluated. Finally, we assessed the effects of HDGF and ibrutinib on the expression of the BTK protein and downstream signal transduction in RAJI cells following anti-IgM stimulation. Computational studies revealed that the inhibitory activity of the obtained [60]fullerene derivative is multifaceted: it hampers the BTK active site, interacting directly with the catalytic residues, rendering it inaccessible to phosphorylation, and binds to residues that form the ATP binding pocket. The anticancer activity of produced carbon nanomaterial revealed that it inhibited the BTK protein and its downstream pathways, including PLC and Akt proteins, at the cellular level. The mechanistic studies suggested the formation of autophagosomes (increased gene expression of LC3 and p62) and two caspases (caspase-3 and -9) were responsible for the activation and progression of apoptosis. These data illustrate the potential of fullerene-based BTK protein inhibitors as nanotherapeutics for blood cancer and provide helpful information to support the future development of fullerene nanomaterials as a novel class of enzyme inhibitors.

Efficient non-viral CAR-T cell generation via silicon-nanotube-mediated transfection

Cell-based immunotherapy such as chimeric antigen receptor (CAR)-T therapy holds great promise in treating cancer and other diseases; but the current viral-based method represents a significant cost and safety hurdle. Here, we show for the first time successful CAR transfection into primary T cells via vertically aligned silicon nanotube (SiNT) arrays. SiNT-mediated transfection achieves comparable or even higher delivery efficiency (20–37%) and expression efficiency (18–24%) to that achieved by electroporation. Scanning electron microscopy imaging after focused ion beam milling demonstrated the tight T cell–SiNT interface. The induced membrane invaginations and the proximity between individual SiNTs and the nucleus might enhance endocytic pathways, and enable direct delivery of CAR construct into the nucleus, thus resulting in higher CAR expression efficiency. SiNT-interfacing also results in faster proliferation of T cells compared to cells transfected by electroporation; non-activated T (N_SiNT) cells undergo higher numbers of cell division than pre-activated ones (A_SiNT). By co-culturing with target lymphoma Raji cells, we prove that SiNT-transfected CAR-T cells can suppress Raji cell growth, indicated by significant increase in effector:target (E:T) ratio (by up to 30.7-fold). While SiNTs induce an overall upregulation of cytokine production in T cells, N_SiNT T cells exhibited high increase in secretion of IFNγ and IL-6, and relatively high in TNFα, which could contribute to their enhanced killing ability (∼96% cytotoxicity), demonstrated by their stronger inhibition on target Raji cells through luciferase assay. The results demonstrate the capacity of SiNT-mediated transfection of generating effective anti-lymphoma CAR-T cells. Considering the growing potential of cell-based therapies, we expect that a non-viral nanoinjection platform such as ours will facilitate the full realization of their therapeutic promise.

Association between CHFR and PARP-1, and Their Roles in Regulation of Proliferation and Apoptosis of B Cell Lymphoma

Background. Aberrant methylation of checkpoint with forkhead and ring finger domains (CHFR) was found in B-cell non-Hodgkin lymphoma (NHL), whereas its role in carcinogenesis is not clear. CHFR can control poly (ADP-ribose) polymerase levels by causing its degradation. The study was aimed to explore the roles and mechanisms of CHFR in the pathogenesis of B-cell NHL. Methods. Short hairpin ribonucleic acid (ShRNAs) targeting CHFR and poly (ADP-ribose) polymerase 1 (PARP-1) were transduced into Raji cells, and real-time polymerase chain reaction (PCR) and western blotting were carried out to determine their expression. Afterwards, the CCK-8 assay and flow cytometry were used to evaluate the cell growth and apoptosis. Tumor size and weight were determined using a xenograft model, and decitabine (5-Aza-dC) was used to further determine the methylation status of CHFR through a methylation specificity-PCR assay. Results. 5-Aza-dC-treatment promoted the expression of CHFR and decreased the expression of PARP-1 at both messenger ribonucleic acid (mRNA) and protein levels. 5-Aza-dC also accelerated Raji-cell apoptosis and restrained its growth in vitro and in vivo ( P < 0.05 ). These results were contrary to those observed in the shRNA-CHFR group but consistent with those observed in the shRNA-PARP-1 group. The expression profiles of CHFR and PARP-1 in the xenograft model were consistent with those in the cellular model. Treatment with 5-Aza-dC led to demethylation of CHFR in nude mice. Besides, there may be a negative correlation between CHFR and PARP-1 in B-cell NHL cells. Conclusion. Our findings indicated that 5-Aza-dC could lead to the demethylation of the CHFR promoter and suppress Raji cell growth.

Cancer Cell-Selective Membrane Receptor Clustering Driven by VEGF Secretion for In Vivo Therapy.

Clustering of cell membrane receptors regulates cell behaviors. Although receptor clustering plans have achieved wide applications in cancer therapy, it still remains challenging to manipulate receptor clustering selectively for cancer cells with little influence on normal cells. Here, we design a Raji cell Selective MAnipulation of Receptor Clustering (SMARC) strategy for CD20, which is driven by endogenous secretion of Raji cells. Retractable DNA nanostrings with repeating hairpin-structured units are anchored to the cell membrane CD20, which contract in response to Raji cell-secreted vascular endothelial growth factor (VEGF) with corresponding CD20 clustering. The contraction of DNA nanostrings is intensified via a VEGF amplifier including DNA cyclic reactions to continuously trigger the foldings of hairpin-structured units in DNA nanostrings. The SMARC strategy shows selective and efficient apoptosis of Raji cells with little interference to normal B cells and demonstrates good in vivo therapeutic efficacy, which provides a promising tool for precise cancer therapy.

Nanobody‐mediated complement activation to kill HIV‐infected cells

The complement system which is part of the innate immune response against invading pathogens represents a powerful mechanism for killing of infected cells. Utilizing direct complement recruitment for complement‐mediated elimination of HIV‐1‐infected cells is underexplored. We developed a novel therapeutic modality to direct complement activity to the surface of HIV‐1‐infected cells. This bispecific complement engager (BiCE) is comprised of a nanobody recruiting the complement‐initiating protein C1q, and single‐chain variable fragments of broadly neutralizing antibodies (bNAbs) targeting the HIV‐1 envelope (Env) protein. Here, we show that two anti‐HIV BiCEs targeting the V3 loop and the CD4 binding site, respectively, increase C3 deposition and mediate complement‐dependent cytotoxicity (CDC) of HIV‐1 Env‐expressing Raji cells. Furthermore, anti‐HIV BiCEs trigger complement activation on primary CD4 T cells infected with laboratory‐adapted HIV‐1 strain and facilitates elimination of HIV‐1‐infected cells over time. In summary, we present a novel approach to direct complement deposition to the surface of HIV‐1‐infected cells leading to complement‐mediated killing of these cells.

T-cells engineered with a novel VHH-based chimeric antigen receptor against CD19 exhibit comparable tumoricidal efficacy to their FMC63-based counterparts.

Chimeric antigen receptor (CAR)-T cell therapy has established itself as a potent therapeutic option for certain patients with relapsed/refractory (R/R) hematologic malignancies. To date, four CD19-redirected CAR-T cell products have been granted the United States Food and Drug Administration (FDA) approval for medical use. However, all of these products are equipped with a single-chain fragment variable (scFv) as their targeting domains. Camelid single-domain antibodies (VHH or nanobody) can also be used as alternatives to scFvs. In this study, we developed VHH-based CD19-redirected CAR-Ts, and compared them with their FMC63 scFv-based counterpart. Human primary T cells were transduced to express a second-generation 4-1BB-CD3ζ-based CAR construct whose targeting domain was based on a CD19-specific VHH. The expansion rate, cytotoxicity, and secretion of proinflammatory cytokines (IFN-γ, IL-2, and TNF-α) of the developed CAR-Ts were assessed and compared with their FMC63 scFv-based counterpart as they were co-cultured with CD19-positive (Raji and Ramos) and CD19-negative (K562) cell lines. VHH-CAR-Ts showed an expansion rate comparable to that of the scFv-CAR-Ts. In terms of cytotoxicity, VHH-CAR-Ts mediated cytolytic reactions against CD19-positive cell lines, comparable to those of their scFv-based counterparts. Moreover, both VHH-CAR-Ts and scFv-CAR-Ts secreted remarkably higher and similar levels of IFN-γ, IL-2, and TNF-α upon co-cultivation with Ramos and Raji cell lines compared with while cultured alone or co-cultured with K562 cells. Our results demonstrated that our VHH-CAR-Ts could mediate CD19-dependent tumoricidal reactions as potently as their scFv-based counterparts. Moreover, VHHs could be applied as the targeting domains of CAR constructs to overcome the issues associated with the use of scFvs in CAR-T therapies.

In Vitro Expansion of Vδ1+ T Cells from Cord Blood by Using Artificial Antigen-Presenting Cells and Anti-CD3 Antibody.

γδ T cells have the potential for adoptive immunotherapy since they respond to bacteria, viruses, and tumors. However, these cells represent a small fraction of the peripheral T-cell pool and require activation and proliferation for clinical benefits. In cord blood, there are some γδ T cells, which exhibit a naïve phenotype, and mostly include Vδ1+ T cells. In this study, we investigated the effect of CD3 signaling on cord blood γδ T-cell proliferation using K562-based artificial antigen presenting cells expressing costimulatory molecules. There were significantly more Vδ1+ T cells in the group stimulated with anti-CD3 antibody than in the group without. In cultured Vδ1+ T cells, DNAM-1 and NKG2D were highly expressed, but NKp30 and NKp44 showed low expression. Among various target cells, Vδ1+ T cells showed the highest cytotoxicity against U937 cells, but Daudi and Raji cells were not susceptible to Vδ1+ T cells. The major cytokines secreted by Vδ1+ T cells responding to U937 cells were Granzyme B, IFN-γ, and sFasL. Cytotoxicity by Vδ1+ T cells correlated with the expression level of PVR and Nectin of DNAM-1 ligands on the surface of target cells. Compared to Vδ2+ T cells in peripheral blood, cord blood Vδ1+ T cells showed varying cytotoxicity patterns depending on the target cells. Here, we determined the ideal conditions for culturing cord blood Vδ1+ T cells by observing that Vδ1+ T cells were more sensitive to CD3 signals than other subtypes of γδ T cells in cord blood. Cultured cord blood Vδ1+ T cells recognized target cells through activating receptors and secreted numerous cytotoxic cytokines. These results are useful for the development of tumor immunotherapy based on γδ T cells.

The Molecular Mechanism of LncRNA HOTAIR Regulating the Proliferation, Invasion and Migration of Lymphoma Cells through Target Gene miR-20a-5p

To investigate the effects of lncRNA HOTAIR on the proliferation, invasion and migration of lymphoma cells through target gene miR-20a-5p and its molecular mechanism. After synthesizing HOTAIR siRNA and siRNA NC plasmids, they were transfected into lymphoma Raji cells, respectively. The expression of HOTAIR mRNA was detected by RT-qPCR. The proliferation, invasion and migration of lymphoma Raji cells were detected by CCK-8 assay, Transwell assay and cell scratch healing assay, respectively. The target gene of lncRNA HOTAIR was predicted by miRcode software, and the relationship between HOTAIR and target gene was analyzed by dual luciferase assay. After synthesis of miR-20a-5p inhibitor and inhibitor NC, Raji cells were transiently transfected. The expression of miR-20a-5p was detected by RT-qPCR, and the effects of down-regulation of miR-20a-5p on the proliferation, invasion and migration of Raji cells were analyzed. The overexpression plasmid of lncRNA HOTAIR and miR-20a-5p mimics were transfected into Raji cells simultaneously to analyze the proliferation, invasion and migration ability of Raji cells. After overexpression or down-regulation of miR-20a-5p, the expression of JAK/STAT3 signaling pathway related proteins was analyzed. HOTAIR expression in Raji cells was decreased after transfection of HOTAIR siRNA (P<0.01), and miR-20a-5p expression was also decreased after transfection of miR-20a-5p inhibitor (P<0.01). HOTAIR had a targeting and negative regulation relationship with miR-20a-5p (r=-0.826). Silencing HOTAIR promoted the expression of miR-20a-5p and inhibited the proliferation, invasion and migration of Raji cells. Down-regulation of miR-20a-5p expression promoted the proliferation, invasion and migration of Raji cells. Effect of HOTAIR overexpression on the proliferation, invasion and migration of Raji cells could be reversed by up-regulation of miR-20a-5p. Down-regulation of miR-20a-5p expression activated the intracellular JAK/STAT3 signaling pathway. HOTAIR affects the proliferation, invasion and migration of lymphoma cells by targeting miR-20a-5p, and its mechanism may be related to the activation of JAK/STAT3 signaling pathway.

Antioxidant, Cytotoxic, and Insulinotropic Activities of Several Leaves Extracts of Medicinal Plants

The prevalence of diabetes mellitus and cancer is increasing; thus, research into efficient treatments utilizing active compounds derived from medicinal plants has focused on these diseases. Through the agro maritime 4.0 approach, medicinal plants are explored in the archipelago of Indonesia, particularly on Tinjil Island, Banten Province. The medicinal plants identified on the island include Morinda citrifolia, Terminalia catappa, and Gnetum gnemon. Therefore, this study aimed to evaluate the in vitro of aqueous extracts of leaves of those three plant species. All aqueous extracts were analyzed for total phenolic content and further tested for antioxidant activity using the DPPH method (2,2-diphenyl-1-picrylhydrazyl), MTT cytotoxic activity (3-[4,5-dimethylthiazole-2-yl]-2- 5-diphenyl-tetrazolium-bromide) in MCF-7- (ATCC HTB 22) and Burkitt’s Lymphoma Raji (ATCC CCL 86) cells, and insulinotropic activity in pancreatic BRIN BD11 cells. The results showed that the total phenolic content of T. catappa was significantly higher (9.21 ± 2.49 mg GAE/g extract sample) compared to M. citrifolia (3.00 ± 0.35 mg GAE/g) and G. gnemon (7.47 ± 0.33 mg GAE/g). Compared to the other two extracts, T. catappa extract has the best DPPH antioxidant activity of IC50 7.44 ± 0.77 µg/mL (p&lt;0.05). MTT cytotoxic activity in all samples did not inhibit the proliferation of Raji cells but did the proliferation of MCF-7 cells. The IC50 for the best cytotoxic activity was shown in M. citrifolia (8.06 µg/mL). T. catappa triggered insulin secretion at 62.5 µg/mL with the highest insulin concentration (54.55 mg/mL). The aqueous extract of T. catappa leaves shows potential as an antioxidant and insulinotropic agent, while M. citrifolia leaves have a cytotoxic effect with anticancer potential.

ArtinM Cytotoxicity in B Cells Derived from Non-Hodgkin's Lymphoma Depends on Syk and Src Family Kinases.

Receptors on the immune cell surface have a variety of glycans that may account for the immunomodulation induced by lectins, which have a carbohydrate recognition domain (CRD) that binds to monosaccharides or oligosaccharides in a specific manner. ArtinM, a D-mannose-binding lectin obtained from Artocarpus heterophyllus, has affinity for the N-glycans core. Immunomodulation by ArtinM toward the Th1 phenotype occurs via its interaction with TLR2/CD14 N-glycans on antigen-presenting cells, as well as recognition of CD3γ N-glycans on murine CD4+ and CD8+ T cells. ArtinM exerts a cytotoxic effect on Jurkat human leukemic T-cell line and human myeloid leukemia cell line (NB4). The current study evaluated the effects of ArtinM on murine and human B cells derived from non-Hodgkin’s lymphoma. We found that murine B cells are recognized by ArtinM via the CRD, and the ArtinM stimulus did not augment the proliferation rate or production of IL-2. However, murine B cell incubation with ArtinM augmented the rate of apoptosis, and this cytotoxic effect of ArtinM was also seen in human B cell-lines sourced from non-Hodgkin’s lymphoma Raji cell line. This cytotoxic effect was inhibited by the phosphatase activity of CD45 on Lck, and the protein kinases of the Src family contribute to cell death triggered by ArtinM.

YIV-906 enhances nuclear factor of activated T-cells (NFAT) activity of T cells and promotes immune checkpoint blockade antibody action and CAR T-cell activity.

YIV-906 is a systems biology botanical cancer drug, inspired by a traditional Chinese herbal formulation. Results from eight Phase I/II to II clinical studies demonstrated the potential of YIV-906 to prolong survival and improve the quality of life of cancer patients. As an immunomodulator in the tumor microenvironment, YIV-906 can turn cold tumors hot and potentiate anti-tumor activity for different classes of anticancer agents; and as a cytoprotector in the GI, YIV-906 can reduce non-hematological side effects and speed up damaged tissue recovery. YIV-906 enhanced anti-PD1 action against hepatoma in mice by stimulating both innate and adaptive immunity. In a Jurkat cell-staphylococcal superantigen E (SEE)-Raji cell culture model, YIV-906 promoted T cell activation with upregulation of CD69 by enhancing NFAT activity, with or without PD1-PD-L1 interaction. YIV-906 could trigger the phosphorylation of TCR downstream signaling cascades without the involvement of TCR. YIV-906 could inhibit SHP1 and SHP2 activities, which dephosphorylates TCR downstream proteins due to the PD1-PD-L1 interaction. Therefore, YIV-906 could enhance anti-PD1 action to rescue the depressed NFAT activity of Jurkat cells due to the PD1-PD-L1 interaction. In addition, YIV-906 enhanced the NFAT activity and killing capability of Jurkat cells expressing chimeric antigen receptor (CAR-CD19-CD3z) toward CD19 expressing cells, such as Raji cells, with or without PD1-PD-L1 overexpression. Ingredient herb S (Scutellaria baicalensis Georgi) of YIV-906 and some S compounds were found to play key roles in these activities. In conclusion, YIV-906 modulates adaptive immunity by activating T effector cells mainly through its action on SHP1/2. YIV-906 could also facilitate immune checkpoint blockade therapy or CAR-T cell therapy for cancer treatment.

Fate of177 Lu-CHX-A”-DTPA-Rituximab

Context: Radioimmunotherapy is an emerging treatment modality for various types of cancers. While immunotherapy using monoclonal antibodies has shown promising results, particularly in hematological malignancies, a significant number of patients develop resistance to the treatment, which may be overcome using monoclonal antibodies labeled with suitable therapeutic radioisotopes. Aim: In this study, in vitro evaluation studies of 177Lu-CHX-A"-DTPA-rituximab were performed in Raji cells that overexpress CD20. The extent of internalization of 177Lu-CHX-A”-DTPA rituximab inside the target cell as well as the impact of cellular toxicity in Raji cells was studied. Materials and Methods: The monoclonal antibody rituximab was labeled with 177Lu using CHX-A”-DTPA as the bifunctional chelator. In vitro cell binding and inhibition studies were performed in Raji cells to ascertain the specificity of the radioimmunoconjugate toward the CD20 receptors. The immunoreactive fraction was determined to evaluate the integrity of the radioimmunoconjugate. A cellular internalization assay was performed to evaluate the extent of internalization of the radioimmunoconjugate, and the extent of cytotoxicity was determined using flow cytometry in comparison with unlabeled rituximab. Results: Radiochemical purity of 177Lu-CHX-A"-DTPA-rituximab was determined to be 97.4% ± 1%. In vitro cell-binding studies in Raji cells showed a cell concentration-dependent increase in the percent cell binding, which surged from 11.7% ± 0.7% to 22.7% ± 0.9%, as the cell concentration increased from 0.94 × 10^6 to 7.5 × 10^6 successively. Inhibition in binding was observed in the presence of unlabeled rituximab (11.7% ± 0.7% to 7.8% ± 1.2% and from 22.7% ± 0.9% to 12.1% ± 1.3%). The immunoreactive fraction was found to be 78.5%. A time-dependent increase in the cellular internalization from 25.21 ± 1.7 to 60.47 ± 0.20 was observed. The percent cell viability decreased from 56% to 41% when the cell was treated with rituximab compared with 177Lu-rituximab. Conclusions: Thus, the results show a potential of 177Lu-rituximab as a promising radiopharmaceutical against non-Hodgkin's lymphoma.

P19 a Parthenin Analog Induces Cell Lineage Dependent Apoptotic and Immunomodulatory Signaling in Acute Lymphoid Leukemia Cells.

Leukemia is a type of cancer that affects the blood and bone marrow. Acute lymphoid leukaemia, also known as ALL, is regarded as one of the deadliest forms of cancer. Due to the rapid increase in various cancer cases and the development of resistance in cancer cells, it is necessary to identify novel lead molecules with more potent anticancer properties. There is a growing interest in using herbal products/analogs as multi-component agents (as anticancer agents and immunomodulators) for cancer treatment. In the present investigation, an attempt has been made to explore the anticancer and immunomodulatory activity of P19, an analog of parthenin in ALL. P19 was reported to exhibit anticancer efficacy by triggering apoptotic signaling events in human leukaemia HL-60 cells by significant NO production. In contrast to this finding, ROS and NO were not required for P19-mediated apoptosis in Raji cells. The mechanism of action of P19 was observed to be cancer cell lineage dependent. P19 demonstrated very effective anticancer properties against ALL (IC50 3µM). Molecular investigations revealed that P19 induced mitochondrion mediated apoptosis by Bax localization to mitochondria and enhanced cytosolic calcium in the cytoplasm. Further activation of the caspase 3, caspase 8 and PARP cleavage suggested the involvement of the caspase-mediated apoptosis. Anti-proliferative activity revealed the telomerase inhibition and cell cycle arrest in G0/G1 phase after P19 treatment. Immunomodulatory effects of the P19 revealed the enhanced INFɣ and NO production in Jurkat and THP cells. Owing to its antiproliferative and immunomodulatory potential against leukemia cells P19 can further be explored as effective therapeutics against leukemia.

Design of an aryne-platform for the synthesis of non-racemic heterocyclic allocolchicinoids.

A four-step semisynthetic approach towards a highly versatile allocolchicine-related chiral aryne intermediate starting from naturally occurring colchicine was developed, and some of its synthetic transformations were studied. The in situ generated benzyne intermediate afforded a number of non-racemic heterocyclic allocolchicinoids, which were shown to exhibit potent cytotoxicity towards COLO 357, OSA and Raji cells. The proposed methodology is attractive for the synthesis of libraries of new cytotoxic tubulin inhibitors.

Synthesis and antiproliferative activity of new thiazole hybrids with [3.3.0]furofuranone or tetrahydrofuran scaffolds

New thiazole hybrids were synthesized and evaluated for their in vitro cytotoxicity against a panel of human malignant cell lines. The key steps in the synthesis of hybrids 3?7 involved the initial condensation of appropriate aldononitriles with cysteine ethyl ester hydrochloride, followed by subsequent treatment of resulting thiazolines with diazabicycloundecene to form the thiazole ring. Bioisosteres 8 and 14 have been prepared after the stereoselective addition of 2-(trimethylsilyl)thiazole to the hemiacetals obtained by periodate cleavage of terminal diol functionality in the suitably protected d-glucose derivatives. The obtained analogues showed various antiproliferative activities in the cultures of several tumour cell lines. Hybrid 6 was the most potent in HeLa cells, exhibiting more than 10 and 4 times stronger activity than both leads 1 and 2, respectively. The most active compound in Raji cells was hybrid 12, which was nearly 2-fold more potent than the clinical antitumour drug doxorubicin. All analogues were more potent in A549 cells with respect to lead 1, while compounds 6 and 7 were slightly more active than doxorubicin. Preliminary structure?activity relationship analysis revealed that the presence of a cinnamate group at the C-3 position in analogues of type 7 increases the activity of resulting molecular hybrids.

Apoptosis of Hematopoietic Stem Cells Contributes to Bone Marrow Suppression Following Chimeric Antigen Receptor T Cell Therapy

Chimeric antigen receptor (CAR) T cell (CAR-T) therapy represents a revolutionary treatment for patients with relapsed/refractory hematologic malignancies. However, its use can result in significant toxicities, including cytokine release syndrome (CRS), a potentially life-threatening clinical syndrome resulting from the release of proinflammatory cytokines upon T cell activation. In addition, patients who develop CRS often experience prolonged cytopenias, and those with the most severe CRS also have the longest delays in full marrow recovery. Although an association between CRS and delayed bone marrow recovery has been established, the precise mechanism underlying this phenomenon remains unknown. This study was conducted to test our hypothesis that delayed bone marrow recovery following CAR-T therapy is caused by elevation of proinflammatory cytokines, leading to apoptosis and depletion of hematopoietic stem and progenitor cells (HSPCs). SCID-beige mice bearing intraperitoneal CD19+ Raji cell tumors were treated with injection of human CD19.28z CAR T cells. Bone marrow was then harvested for analysis by flow cytometry, and HSPCs were isolated for whole-transcriptome analysis by RNA sequencing. Complete blood counts and serum cytokine levels were measured as well. A second model was developed in which SCID-beige mice were treated with murine IFN-γ (mIFN-γ), murine IL-6 (mIL-6), or both. Bone marrow was harvested, and flow cytometry assays were conducted to evaluate the degree of apoptosis and proliferation on specific HSPC populations. SCID-beige mice bearing intraperitoneal Raji cell tumors that were treated with CAR-T therapy developed CRS, with elevations of several proinflammatory cytokines, including profound elevation of human IFN-γ. Gene set enrichment analysis of RNA sequencing data revealed that genes associated with apoptosis were significantly upregulated in HSPCs from mice that developed CRS. Endothelial protein C receptor (EPCR)-negative HSCs, a subset of HSCs that is poised for terminal differentiation, was found to be specifically decreased in mice that were treated with CAR T cells. Furthermore, HSPCs were found to have increased levels of apoptosis upon treatment with mIFN-γ and mIL-6, whereas short-term HSCs and multipotent progenitors exhibited increases in proliferation with mIFN-γ treatment alone. The results from this study provide evidence that the elevation of proinflammatory cytokines following CAR-T therapy impacts the bone marrow through a combined mechanism: pluripotent HSCs that are exposed to elevated levels of IFN-γ and IL-6 undergo increased cell death, while more committed progenitor cells become more proliferative in response to elevated IFN-γ. These combined effects lead to depleted stores of repopulating HSCs and ultimately cytopenias. © 2023 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

IN VITRO ANTILEUKEMIC ACTIVITY OF EUPHORBIA ECHINUS EXTRACT

Aim. Cancer continues to pose a serious threat to human health. Euphorbia plants are rich in phenolics, aromatic esters, steroids and several bioactive compounds. Studies have shown the presence of a large number of bioactive compounds in E. echinus including flavonoids, phenolics, and proanthocyanins. Method. There it was investigated cytotoxic effects of E. echinus methanolic extract on K562, HL60, Ishikawa, Raji and SH-SY5Y cells. Results. The E. echinus extract was found to be highly cytotoxic against HL60 and K562 (79.78 and 76.44% cytotoxicity, respectively). DNA fragmentation was exclusively observed in K562 cells indicating that the reduction of viable cells following treatment with E. echinus extract is due to apoptosis. Conclusions. Our results suggest that E. echinus extract might have a drug potential against leukemic cells.

Marine Sponge-Derived Alkaloid Induces Mitochondrial Dysfunction and Inhibits the PI3K/AKT/mTOR Signaling Pathway against Burkitt's Lymphoma.

Burkitt's lymphoma (BL) has a particularly extremely poor prognosis and the fastest growth rate among human tumors, and the development of new drugs for the treatment of BL is urgently needed. In this study, the cytotoxic properties of 3,7-bis(3,5-dimethylphenyl)-aaptamine (AP-51), a new semisynthetic alkaloid derived from the marine natural product aapatamine, were investigated using BL cell lines. Our results showed that AP-51 inhibited the proliferation of Daudi and Raji cells with IC50 values of 3.48 and 2.07 μM, respectively. Flow cytometry and Western blot analyses showed that AP-51 initiated G0/G1 phase arrest by modulating the expression of cyclin-dependent kinases (CDKs). AP-51 also induced apoptosis, as demonstrated by nuclear fragmentation, downregulation of BCL-XL and Mcl-1, and upregulation of cleaved caspase-9, cleaved caspase-3, cleaved-PARP, and cytochrome c, the markers of apoptosis regulated via the mitochondrial pathway. When it comes to mitochondria, AP-51 treatment also significantly increased the levels of intracellular mitochondrial superoxide, decreased ATP content, and reduced the expression of ATP synthase, as well as the expression of the mitochondrial respiratory chain complexes. Finally, AP-51 treatment significantly inhibited the PI3K/AKT/mTOR signaling pathway, which was shown to be associated with the induction of apoptosis. Collectively, these findings indicated that AP-51 initiated cell cycle arrest, induced apoptosis, caused mitochondrial dysfunction, and decreased the phosphorylation of PI3K/AKT/mTOR signaling pathway-related proteins and the protein levels of C-MYC, suggesting that AP-51 has therapeutic potential as a possible treatment for Burkitt's lymphoma.

Fangchinoline Inhibited Proliferation of Neoplastic B-lymphoid Cells and Alleviated Sjögren's Syndrome-like Responses in NOD/Ltj Mice via the Akt/mTOR Pathway.

Fangchinoline is a bisbenzylisoquinoline alkaloid extracted from Stephania tetrandra S. Moore that is conventionally used as an analgesic, antirheumatic, and antihypertensive drug in China. However, the application of Fanchinoline in Sjögren syndrome (SS) remains unreported. This study aimed to identify the potential role of Fangchinoline in the treatment of SS via altering Akt/mTOR signaling. First, we examined levels of p-Akt and p-mTOR in infiltrating lymphocytes of labial glands from SS patients by immunohistochemistry. Then, the effects of Fangchinoline on Raji cells and Daudi cells were investigated using the CCK-8 assay, propidium iodide (PI)/RNase, and Annexin V/PI staining. Western blotting was used to identify the levels of Akt, p-Akt(ser473), mTOR, and p-mTOR. For in vivo analyses, NOD/Ltj and wild-type ICR mice were treated with a Fangchinoline solution, an LY294002 solution (an inhibitor of the PI3K/Akt/mTOR pathway), or their solvent for 28 days. Then, salivary flow assays and hematoxylin and eosin staining of submandibular glands were performed to determine the severity of SS-like responses in the mice. Immunohistochemical staining of labial glands from SS patients showed that activation of p-Akt and p-mTOR in infiltrating lymphocytes might be correlated with SS development. In vitro, Fangchinoline and LY294002 inhibited proliferation, induced cell cycle arrest, and promoted apoptosis in Raji and Daudi cells by altering Akt/mTOR signaling. In vivo, Fangchinoline and LY294002 significantly improved the salivary secretion by NOD/Ltj mice and reduced the number of lymphocytic foci in the submandibular glands. These results indicated that Fangchinoline could effectively inhibit the proliferation of neoplastic B-lymphoid cells and reduce SS-like responses in NOD/Ltj mice. Our study highlights the potential value of the clinical application of Fangchinoline for SS treatment.