Antimitotic Research Articles

Brentuximab Vedotin Combined with Chemotherapy in the Treatment of Pediatric Patients with R/R Hodgkin Lymphoma: Results of a Real World Setting Study

INTRODUCTION: Hodgkin Lymphoma (HL) is a familiar malignant lymphoma of the lymphatic system that accounts for 10% of all lymphoma diagnoses and 5% of lymphoma-related deaths. According to statistics, the incidence of HL in children and adolescents (0-19 years old) in China is about 1.78/million, and an average of 569 new cases are estimated annually from 2019 to 2021 . Brentuximab vedotin (BV) is an antibody-drug conjugates (ADC) that selectively delivers monomethyl auristatin E, an antimicrotubule agent, into CD30-expressing cells. Most of the data on the efficacy and safety of BV came from prospective and retrospective studies in adults or foreign children, and there are insufficient data in Chinese children. The purpose of this study is to explore the efficacy and safety of BV Combined with chemotherapy in Chinese pediatric patients with refractory and/or relapsed Hodgkin's lymphoma. METHODS: Retrospective analysis of clinical data of 9 children with refractory and/or relapsed Hodgkin's lymphoma from October 2021 to May 2023 at Beijing Children's Hospital, Capital Medical University. Patients were classified according to: clinical stage(Ann Arbor stage), huge tumor, huge tumor in the mediastinum, symptoms of B, and whether multiple lymph nodes were involved. Among them, the low-risk group was IA, ⅡA without giant tumor. The middle risk group was IB and ⅢA without huge tumor. High-risk groups were patients with stage ⅡB, ⅢB, Ⅳ or (each stage) with large tumors, or children with > 4 lymph node regions. All patients received BV in combination with chemotherapy for at least 2 cycles, and patients were assessed for remission response according to the Revised Response Criteria for Malignant Lymphoma at the end of every 2 cycles and followed up until July 20, 2023. RESULTS: Totally 32 cycles of chemotherapy were recorded, including 36 doses of BV administration(Table 1). The overall response rate of the children after 2 cycles of treatment was 100%, and the complete response rate was 88.89%. After remission, 2 cases (P1, P2) were treated with BV single drug 1.8mg/kg, Q3W for 6 months, and 3 cases (P3, P4, P7) were treated with radiotherapy. Two patients (P5, P6) received sequential chemotherapy, and two patients (P8, P9) were followed by programmed cell death 1(PD-1) antibody maintenance treatment for 6 months. After receiving PD-1 antibody for 6 months, 1 patient (P9) was transferred to BV monotherapy for maintenance, with 18 times planned. 2 cases (P1, P2) were then treated with autologous stem cell transplantation. None of the children developed disease progression during treatment. All patients successfully completed all planned dosage of BV, and serious adverse events were dominated by grade 3 or higher hematocrit, none of which interfered with normal treatment. Interpretation. BV had demonstrated the better efficacy and tolerable safety profile in the treatment of refractory and/or relapsed Hodgkin's lymphoma in children. CONCLUSIONS: BV has been approved by National Medical Products Administration in China since 2020, the clinical cases are mostly from adult lymphoma patients, and children data of in China is rare. In this study, we retrospectively reviewed and analyzed the data of BV combined chemotherapy in the treatment of refractory and relapsed Hodgkin lymphoma from single center, and found that the treatment response was rapid, continuousand safe. However, this study is a single-center retrospective study with a small sample size So We are conducting a prospective study of BV in first-line Hodgkin lymphoma children patients in China and aiming to generate more data for this specific population.

Development of First in Class DNA-Zip Code Drug Conjugate (ZDC) in Multiple Myeloma

Multiple myeloma is a heterogeneous malignant plasma cell disorder with complex molecular and genetic abnormalities. Significant advances have been made in the treatment of multiple myeloma; however, a large proportion of patients fail to attain a favorable response and relapse. Due to efficacy and toxicity, the development of drug conjugates for multiple myeloma has been limited. Our lab discovered that circulating tumor DNA (ctDNA) serves as a cell-specific mechanism for genetic transmission. Certain retrotransposon sequences within the ctDNA were identified as being crucial for the tropism of ctDNA to target tumor cells (Cinar et al bioRxiv.2022). We therefore query whether these transposons can be exploited for the targeted drug delivery. To do so, chemically synthetize and CY5-labeled multiple retrotransposons DNA sequences (a.k.a Zip Codes, ZC) to perform high through put screening assessing for cell targeting. Our findings showed that the AluSp and MER11c DNA sequences (MM-ZC1 and 2) with unique MM mutations were the most efficient and specific DNA sequences for targeting myeloma cells. Furthermore, Flow cytometry and CYTOF validated the specific MM cell targeting on full bone marrow samples from MM patients. Based on this analysis we used MMZC1 for further drug development. We design a drug conjugation approach for the MMZC and screen various drugs for their killing potential. Two potent MM ZC drug conjugates (ZDC) were identified by high throughput viability screening assay: ZC-DM4, a microtubule inhibitor, and ZC-Carfilzomib, an irreversible proteasome inhibitor. We move forward exploration with ZC-DM4 due to limited carfilzomib-linker drug availability. Experiments cancer cell lines in vitro demonstrated that MMZC-DM4 had a potent killing effect on MM cells (IC50: 3.25 nM) but not on other cancer cell lines. These results were the validated in vivo. Maximum tolerated dosing studies (MTD) demonstrated excellent tolerability in all doses (ranges from 1 to 20 mg of MMZC-DM4/Kg (equivalent to 0.007-0.149 mg of DM4/kg). To look for an efficacy signal of MMZC-DM4, MM xenograft mice were given MMZC-DM4 twice a week for three weeks. Due to limitations in production, we treated the animals biweekly with three distinct low doses of MMZC-DM4: 1.9, 3.75, and 7.5 mg/kg (equivalent to 0.014, 0.028, and 0.056 mg of DM4/kg) and compared their response to mice not treated with MMZC-DM4 and mice treated weekly with bortezomib. MMZC-DM4 at such small doses reduced the tumor by 30% without affecting body weight, WBC, HB, AST, or platelets. In contrast, Bortezomib was associated with 90% growth inhibition at the expense of significant weight loss that required treatment interruptions and thrombocytopenia. Currently, investigations are being conducted to examine the therapeutic efficacy of greater doses of MMZC-DM4. This study described the first-in-class MM targeted medicine delivery employing an MM zic code drug conjugate. Our findings suggest new method for targeted delivery therapeutic cargo material directly to cancer cells that could revolutionize cancer treatment.

Measuring Drug Response with Single-Cell Growth Rate Quantification.

Intratumoral heterogeneity is a substantial cause of drug resistance development during chemotherapy or other drug treatments for cancer. Therefore, monitoring and measuring cell exposure and response to drugs at the single-cell level are crucial. Previous research suggested that the single-cell growth rate can be used to investigate drug-cell interactions. However, currently established methods for quantifying single-cell growth are limited to isolated or monolayer cells. Here, we introduce a technique that accurately measures both 2D and 3D cell growth rates using label-free ratiometric stimulated Raman scattering (SRS) microscopy. We use deuterated amino acids, leucine, isoleucine, and valine, as tracers and measure the C-D SRS signal from deuterium-labeled proteins and the C-H SRS signal from unlabeled proteins simultaneously to determine the cell growth rate at the single-cell level. The technique offers single-cell level drug sensitivity measurement with a shorter turnaround time (within 12 h) than most traditional assays. The submicrometer resolution of the imaging technique allows us to examine the effects of chemotherapeutic drugs, including kinase inhibitors, mitotic inhibitors, and topoisomerase II inhibitors, on both the cell growth rate and morphology. The capability of quantifying 3D cell growth rates provides insight into a deeper understanding of the cell-drug interaction in the actual tumor environment.

Zilovertamab Vedotin (MK-2140) in Relapsed or Refractory Diffuse Large B-Cell Lymphoma (DLBCL): Updated Results from the Phase 2 Waveline-004 Study

Background: DLBCL is an aggressive non-Hodgkin lymphoma (NHL) that is often curable with frontline therapy, but up to 50% of patients (pts) will develop relapsed or refractory (R/R) disease. Treatment options are limited for pts with R/R DLBCL who have progressed after or are ineligible for autologous stem cell transplant (ASCT) or chimeric antigen receptor (CAR) T-cell therapy. ROR1 is an oncofetal transmembrane protein that is expressed in DLBCL. Zilovertamab vedotin, an antibody-drug conjugate comprising a humanized monoclonal antibody against ROR1, a proteolytically cleavable linker, and the antimicrotubule agent monomethyl auristatin E (MMAE), initially demonstrated promising antitumor activity and manageable safety in R/R NHL in the phase 1 waveLINE-001 study. Early results from the single-arm, open-label, phase 2 waveLINE-004 study (NCT05144841) showed that zilovertamab vedotin had clinically meaningful antitumor activity and manageable safety in pts with R/R DLBCL who progressed after or were ineligible for ASCT and/or CAR T-cell therapy. We present updated results from waveLINE-004. Methods: Eligible pts were ≥18 y, had histologically confirmed R/R DLBCL per WHO classification, measurable disease per Lugano 2014 criteria, PET-positive disease, and an ECOG performance status of 0 to 2. Pts were required to have disease progression after ≥2 prior lines of therapy including an alkylating agent, anthracycline, and an anti-CD20 antibody, and had progressed after or were ineligible for ASCT and CAR T-cell therapy. Pts received zilovertamab vedotin 2.5 mg/kg IV Q3W until disease progression, unacceptable toxicity, or withdrawal. Primary end point was ORR per Lugano 2014 criteria. Secondary end points were DOR and safety and tolerability. PFS and OS were exploratory. Efficacy is reported for pts who had ≥1 postbaseline assessment available. Safety is reported for all pts who received ≥1 dose of zilovertamab vedotin. Results: At the data cutoff (April 26, 2023), 98 pts had been enrolled and received ≥1 dose of zilovertamab vedotin; 61 pts (62%) had discontinued treatment predominantly because of disease progression (38%); 37 pts (38%) were ongoing. Median age was 66 y (range, 19-88), 63 pts (64%) were male, and 86 (92%) had an ECOG performance status of 0 or 1. Most pts (n = 70; 71%) had received ≥3 prior lines of therapy. Forty-one (42%) and 13 pts (13%) had high-intermediate and high-risk NCCN-IPI scores, respectively. Fifteen pts (15%) had undergone prior ASCT, 18 (18%) had undergone prior CAR T-cell therapy, and 5 (5%) had undergone both ASCT and CAR T-cell therapy. Median time from first dose to data cutoff was 4.5 mo (range, 0.2-13.2) for pts who received ≥1 dose of zilovertamab vedotin, and 5.6 mo (range, 0.9-13.2) for the 79 pts who had ≥1 postbaseline scan (efficacy analysis population). ORR per investigator review was 29% (95% CI, 19.4-40.4), with 10 pts (13%) having a complete response and 13 (16%) a partial response; 10 pts (13%) had stable disease, for a disease control rate of 42% (95% CI, 30.8-53.4). Median DOR was 3.0 mo (range, 0.0+ to 8.8+). Median PFS was 2.5 mo (95% CI, 1.9-3.0); 6-mo PFS was 15%. Median OS for all 98 pts was 10.6 mo (95% CI, 5.1-NR); 6-mo OS was 62%. Treatment-related AEs occurred in 78 pts (80%), most commonly (≥20%) neutrophil count decreased (n = 47; 48%), anemia (n = 25; 26%), diarrhea (n = 23; 23%), and white blood cell count decreased (n = 20; 20%). Grade 3-5 treatment-related AEs occurred in 51 pts (52%), most commonly (≥10%) neutrophil count decreased (n = 38; 39%), anemia (n = 15; 15%), and white blood cell count decreased (n = 12; 12%). Two pts (2%) died because of treatment-related AEs (septic shock, acute kidney injury). Four pts (4%) discontinued zilovertamab vedotin because of treatment-related AEs (2 diabetic ketoacidosis, 1 septic shock, 1 acute kidney injury). Peripheral neuropathy occurred in 18 pts (18%), 2 (2%) of whom had a grade 3/4 event. Dose modification because of peripheral neuropathy was required for 10 pts (10%). One pt (1%) experienced a grade 2 treatment-related infusion reaction. Conclusions: In this updated analysis of waveLINE-004, zilovertamab vedotin continued to demonstrate clinically meaningful antitumor activity in pts with R/R DLBCL who had progressed after or were ineligible for ASCT and/or CAR T-cell therapy. The safety profile of zilovertamab vedotin was manageable, and consistent with the known profile of MMAE-containing agents.

Efficacy and Safety of Polatuzumab Vedotin in Follicular Lymphoma: A Systematic Review of Clinical Trials

Introduction: Polatuzumab vedotin (Pola) is a humanized anti-CD79b monoclonal antibody linked with antimitotic agent monomethyl auristatin E. On internalization, the linker is cleaved, and antimitotic activity inhibits the cell division and growth of cancer cells. Pola is tested in multiple combinations in relapsed/refractory (RR) follicular lymphoma (FL) in recent years. In this systematic study, we will assess the efficacy and safety of Pola based combinations in RR FL. Methods: A literature search was performed on PubMed with keywords, “Polatuzumab vendotin” and “lymphoma” from the inception of data till 07/01/2023. PRISMA guidelines were followed while conducting this systematic review. We reviewed 160 articles and included 1 randomized clinical trial (RCT, N=41), and 4 non-randomized clinical trials (nRCT, N=163) based on inclusion criteria. Data was extracted for complete response (CR), partial response (PR), overall response (ORR), progression free survival (PFS), overall survival (OS) and ≥grade 3 side effects. Results: In 5 trials (N=204), 13 patients with Pola + atezolizumab (Ate) + obinutuzumab (Obi), 49 patients with Pola + Obi + venetoclax (Ven), 39 patients with Pola + Obi, 62 with Pola + Obi + lenalidomide (Len), and 20 patients with Pola + rituximab (Rit). In an RCT by Morschhauser et al. (N=41), Pola + Rit was compared with pinatuzumab vedotin (Pina) + Rit. ORR, CR, PR, and mPFS was 70%, 45%, 25%, and 15.3 months, respectively with Pola + Rit, as compared to 62%, 5%, 57%, and 12.7 months, respectively, with Pina + Rit. In a trial by Philips et al. (N=39), ORR, CR, PR, and mPFS were 67%, 36%, 31%, and 11.5 months, respectively. In 3 nRCTs (N=124), three drug regimens were used with Pola and Obi as backbone. ORR, CR, PR were 50%-83%, 20%-61%, and 20%-39%. Table 1. ≥ Grade 3 hematological and non-hematological side effects are given in table 1. Conclusion: Pola was well tolerated by most of the patients with FL alone or in combination with Obi, Rit, Len, Ven. Pola had relatively better response and survival rates as compared to Pina in combination with Rit. In early phase clinical trials, three drug regimens of Pola and Obi with Ven, and Len were effective in the treatment of heavily pretreated follicular lymphoma. In an early phase trial, Pola + Obi + Ate had limited efficacy in FL with safety concerns. More randomized double blind multicenter phase III clinical trials are needed to confirm these results.

Discovery of a Dual Tubulin and Neuropilin-1 (NRP1) Inhibitor with Potent In Vivo Anti-Tumor Activity via Pharmacophore-based Docking Screening, Structure Optimization, and Biological Evaluation.

Dual inhibition of tubulin and neuropilin-1 (NRP1) may become an effective method for cancer treatment by simultaneously killing tumor cells and inhibiting tumor angiogenesis. Herein, we identified dual tubulin/NRP1-targeting inhibitor TN-2, which exhibited good inhibitory activity against both tubulin polymerization (IC50 = 0.71 ± 0.03 μM) and NRP1 (IC50 = 0.85 ± 0.04 μM). Importantly, it significantly inhibited the viability of several human prostate tumor cell lines. Further mechanism studies indicated that TN-2 could inhibit tubulin polymerization and cause G2/M arrest, thereby inducing cell apoptosis. It could also suppress cell tube formation, migration, and invasion. Moreover, TN-2 showed obvious antitumor effects on the PC-3 cell-derived xenograft model with negligible side effects and good pharmacokinetic profiles. These data demonstrate that TN-2 could be a promising dual-target chemotherapeutic agent for the treatment of prostate cancer.

Genome-wide CRISPR/Cas9 screening for drug resistance in tumors

Genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated nuclease 9 (Cas9) screening is a simple screening method for locating loci under specific conditions, and it has been utilized in tumor drug resistance research for finding potential drug resistance-associated genes. This screening strategy has significant implications for further treatment of malignancies with acquired drug resistance. In recent years, studies involving genome-wide CRISPR/Cas9 screening have gradually increased. Here we review the recent application of genome-wide CRISPR/Cas9 screening for drug resistance, involving mitogen-activated protein kinase (MAPK) pathway inhibitors, poly (ADP-ribose) polymerase inhibitors (PARPi), alkylating agents, mitotic inhibitors, antimetabolites, immune checkpoint inhibitors (ICIs), and cyclin-dependent kinase inhibitors (CDKI). We summarize drug resistance pathways such as the KEAP1/Nrf2 pathway MAPK pathway, and NF-κB pathway. Also, we analyze the limitations and conditions for the application of genome-wide CRISPR/Cas9 screening techniques.

Synthesis, Characterization and Biological Evaluation of New Enamide Fluorinated‐Schiff Base Derivatives as Potential Cytotoxic and Apoptosis‐Inducing Agents

AbstractIn search for new anticancer candidates, a new series of enamide fluorinated‐Schiff base derivatives were synthesized and confirmed by spectroscopic techniques as well as elemental microanalyses. The newly prepared compounds were evaluated for their cytotoxic activity on MCF‐7 breast adenocarcinoma cell line. The benzaldehyde Schiff base and furfural Schiff base derivatives (IC50=3.67±0.15 and 2.06±0.08 μM, respectively) were found to be the most potent molecules of all the tested derivatives against the MCF‐7 cancer cells. Additionally, the furfural Schiff base compound was more potent than colchicine by 1.74‐fold, while benzaldehyde Schiff base compound was nearly equipotent with colchicine as standard drug. In addition to tubulin inhibition activity, enamide‐furfural Schiff base molecule caused cell cycle arrest in MCF‐7 cells at the G2/M phase (2.62‐fold more than control MCF‐7) and induced apoptotic death (48.97‐fold compared to untreated MCF‐7 control) as indicated by FACS analysis. Furthermore, apoptotic studies conducted by enamide‐furfural Schiff base derivative were accomplished by downregulation of mitochondrial membrane potential by 1.56‐fold relative to control untreated cells.

MitoCur-1 induces ferroptosis to reverse vemurafenib resistance in melanoma through inhibition of USP14.

Melanoma is an aggressive malignant tumor with a poor prognosis. Vemurafenib (PLX4032, vem) is applied to specifically treat BRAF V600E-mutated melanoma patients. However, prolonged usage of vem makes patients resistant to the drug and finally leads to clinical failure. We previously tested the combination regimen of tubulin inhibitor VERU-111 with vem, as well as USP14 selective inhibitor b-AP15 in combination with vem, both of which have showed profound therapeutic effects in overcoming vem resistance invitro and invivo. Most importantly, we discovered that vem-resistant melanoma cell lines highly expressed E3 ligase SKP2 and DUB enzyme USP14, and we have demonstrated that USP14 directly interacts and stabilizes SKP2, which contributes to vem resistance. These works give us a clue that USP14 might be a promising target to overcome vem resistance in melanoma. MitoCur-1 is a curcumin derivative, which was originally designed to specifically target tumor mitochondria inducing redox imbalance, thereby promoting tumor cell death. In this study, we have demonstrated that it can work as a novel USP14 inhibitor, and thus bears great potential in providing an anti-tumor effect and sensitizing vem-resistant cells by inducing ferroptosis in melanoma. Application of MitoCur-1 dramatically induces USP14 inhibition and inactivation of GPX4 enzyme, meanwhile, increases the depletion of GSH and decreases SLC7A11 expression level. As a result, ferrous iron-dependent lipid ROS accumulated in the cell, inducing ferroptosis, thus sensitizes the vem-resistant melanoma cell. Interestingly, overexpression of USP14 antagonized all the ferroptosis cascade events induced by MitoCur-1, therefore, we conclude that MitoCur-1 induces ferroptosis through inhibition of USP14. We believe that by inhibition of USP14, vem resistance can be reversed and will finally benefit melanoma patients in future.

Programmed initiation and enhancement of cGAS/STING pathway for tumour immunotherapy via tailor-designed ZnFe2O4-based nanosystem.

The cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)/stimulator of interferon genes (STING) signalling pathway has been a promising target for anticancer immunity, but rationally activating and enhancing this pathway in tumour cells is critical. Herein, a glutathione sensitive ZnFe2O4-based nanosystem is developed to programmatically initiate and enhance the STING signalling pathway in tumour cells. The prepared ZnFe2O4 nanoparticles were coated with cancer cell membrane (CCM), which enabled the nanosystem target tumour cells. In tumour cells, ZnFe2O4 nanoparticles could be disintegrated by responding to high level glutathione, and the released Fe3+ generated reactive oxygen species to induce the DNA leakage into the cytoplasm to stimulate cGAS. Then Zn2+ promoted cGAS-DNA phase separation to intensify the cGAS enzymatic activity. In addition, the low dose encapsulation of paclitaxel (PTX) acting as an antimitotic agent (ZnFe2O4-PTX@CCM) ensured the sustained activation of cGAS/STING pathway. The in vitro and in vivo results confirmed that ZnFe2O4-PTX@CCM elevated the cGAS/STING activity, promoted dendritic cell maturation, increased cytotoxic T lymphocyte and natural killer cells infiltration, eventually inhibiting the tumour progress and postoperative recurrence. This study provided feasible references on constructing STING activation nanosystem for tumour immunotherapy.

RBIO-05. MITOTIC ENRICHMENT AS AN EFFICIENT RADIOSENSITIZATION STRATEGY FOR INTRACRANIAL TUMORS

Abstract Radiotherapy remains one of the most effective modalities for anticancer treatment and part of standard of care for many primary and metastatic brain tumors. Boosting the efficacy of radiotherapy is therefore a logical avenue to improve patient survival. We have developed a radiosensitization strategy called ‘induction of mitotic enrichment’. It has long been known that the radiosensitivity of a cell depends on the phase of the cell cycle and that mitotic cells are especially vulnerable. Enriching the tumor for mitotic cells by arresting them during division prior to each radiotherapy fraction should therefore render the tumor population more sensitive to irradiation. Ideally, induction of mitotic enrichment should be reversible and non-cytotoxic to prevent healthy tissue toxicity and be compatible with clinically applied fractionated radiotherapy regimens. We have now identified an orally available targeted tubulin polymerization inhibitor that can achieve repeated and reversible mitotic enrichment for up to 10 hours prior to radiotherapy, without causing cytotoxicity in vitro or healthy tissue toxicity in vivo. This tubulin inhibitor (ABT-751) efficiently radiosensitizes a range of preclinical tumor models representing adult and pediatric, primary and metastatic brain tumors. Importantly, ABT-751 also improves survival in mouse models of adult glioblastoma (GBM), but only in a mitotic enrichment setup when given several hours prior to radiotherapy to allow accumulation in mitosis. Of note, induction of mitotic enrichment does not exacerbate healthy tissue toxicity. To conclude, induction of mitotic enrichment by ABT-751 radiosensitizes adult GBM to fractionated radiotherapy. We are currently expanding our preclinical development of mitotic enrichment as a radiosensitization strategy to other targets and cancers and have designed a phase 0/I trial for adult GBM to demonstrate induction of mitotic enrichment and tolerability when combined with radiotherapy. We expect to start enrollment in this trial soon.

Performance of the FACT-GOG-Ntx to assess chemotherapy-induced peripheral neuropathy (CIPN) in pediatric high risk Hodgkin lymphoma: report from the Children’s Oncology Group AHOD 1331 study

BackgroundChemotherapy-induced peripheral neuropathy (CIPN) is an under-recognized complication of several chemotherapy agents used as part of curative-intent therapy for Hodgkin Lymphoma (HL). In the absence of validated self- or proxy-report measures for children and adolescents, CIPN reporting has relied on clinician rating, with grading scales often restricted to severe manifestations. In a proof-of-concept study, we assessed the feasibility and psychometric performance of the Functional Assessment of Cancer Therapy-Gynecologic Oncology Group-Neurotoxicity (FACT-GOG-Ntx), a unidimensional CIPN symptom scale widely used adults with CIPN, in pediatric HL at risk for CIPN.MethodsYouth (11+ years) and parents of all children (5–17.9 years) with newly diagnosed high-risk HL enrolled on Children’s Oncology Group AHOD1331 (NCT02166463) were invited to complete the FACT-GOG-Ntx and a health-related quality of life (HRQL) measure at pre-treatment (Time 1), and during cycles 2 (Time 2) and 5 (Time 3) of chemotherapy during the first half of study accrual. Clinical grading of CIPN by providers was also assessed using the Balis Pediatric Neuropathy Scale. We evaluated Cronbach’s alpha, construct validity, and agreement between raters. Change in FACT-GOG-Ntx scores over time was assessed using a repeated measures model.Results306 patients had at least one completed FACT-GOG-Ntx with time-specific completion rates of > 90% for both raters. Cronbach’s alpha was > 0.7 for youth and parent-proxy report at all time points. Correlations between FACT-GOG-Ntx and HRQL scores were moderate (0.41–0.48) for youth and parent-proxy raters across all times. Youth and parent-proxy raters both reported worse FACT-GOG-Ntx scores at Time 3 for those who had clinically-reported CIPN compared to those who did not. Agreement between raters was moderate to high. Compared to baseline scores, those at Time 3 were significantly lower for youth (β = − 2.83, p < 0.001) and parent-proxy raters (β = − 1.99, p < 0.001).ConclusionsHigh completion rates at all time points indicated feasibility of eliciting youth and parent report. Psychometric performance of the FACT-GOG-Ntx revealed acceptable reliability, evidence of validity, and strong inter-rater agreement, supporting the use of this self- or proxy-reported measure of CIPN in youth with high-risk HL exposed to tubulin inhibitors, as part of a Phase 3 clinical trial.Clinical trial information: Clinical Trials Registry, NCT02166463. Registered 18 June 2014, https://clinicaltrials.gov/ct2/show/study/NCT02166463

EVALUATION OF CALCIUM CARBIDE'S CYTOTOXIC EFFECTS ON ONION (Allium cepa)

The purpose of this investigation was to see if Calcium Carbide (CaC2) had any harmful effects on onions (Allium cepa L.). Allium cepa root tips were grown in various concentrations of Calcium Carbide (CaC2) (0.25g, 0.50g, 0.75g, and 1.00g)/ 250ml, with distilled water serving as a control. For cytological tests, the root tips of Allium cepa growing in the treatments and control were removed daily between 7:30am and 8:30am. Pretreatment, fixation, hydrolysis, squashing, and staining of cells for mitotic investigations were performed, and data on cytological parameters were collected using a light microscope at a magnification of X40. The mitotic index (MI) and karyotype analysis were used to assess the data collected on these parameters. The results of this study showed that root tips treated with 0.25g of Calcium Carbide (CaC2) have a mitotic index of 45.83 and the rate of cell division decreases with an increase in the concentration of Calcium Carbide (CaC2) as the cell divides the mitotic index dropped sharply. These finding indicated that Calcium Carbide is a strong mitotic inhibitor and could give rise to mitotic abnormalities with increase in concentration and also reduced cell division. We therefore recommended that there is need for further investigation using lower concentrations of Calcium Carbide as well as other mutagenic substances in order to ascertain their effect on the chromosomal behavior.

Indicators of Response to the Wee1 Inhibitor Adavosertib in Acute Myeloid Leukemia

Wee1 is a nuclear kinase that regulates cell cycle progression by inhibiting Cdk1, which is essential for G2 to M phase transition. Inhibition of Wee1 leads to high Cdk1 activity, causing cells to bypass proper DNA repair at the G2/M checkpoint, resulting in mitotic catastrophe and cell death, plus increased Cdk2 activity, causing abnormal DNA replication and DNA double-stranded breaks. Inhibitors of Wee1 are being investigated for the treatment of a variety of cancers including AML. In this study, we aimed to identify biomarkers for Wee1 inhibitor (Wee1i) response in AML using ex vivo drug sensitivity data, bulk RNA sequence, exome sequence, and associated clinical data for a large set of primary AML samples tested against the Wee1i adavosertib. Mononuclear cells from bone marrow aspirates (n=136) or peripheral blood samples (n=11) were collected from AML patients using approved protocols and after informed consent. 101 samples were collected at the time of diagnosis and 35 samples were from relapsed/refractory (R/R) patients. For ex vivo drug-sensitivity testing, freshly isolated cells were tested against a library of up to 634 oncology drugs (215 approved drugs) including adavosertib. The drugs were pre-plated in 5 concentrations in a 10,000-fold concentration range and incubated with cells for 72h. Cell viability was assessed using the CellTiter Glo (CTG) assay, and a drug sensitivity score (DSS) calculated based on the area under the dose response curve. Somatic alterations of the drug tested samples were identified via exome sequencing of DNA from the AML samples and matched skin biopsy controls. Gene expression data were obtained from bulk RNA sequence data of the AML samples. Out of 136 samples analyzed, the median DSS for adavosertib was 8.45. We found positive and significant correlations between sensitivity to adavosertib and two factors: 1) malignant cell percentage (R= 0.31, p-value= 0.0097), and 2) final relative viability percentage (R=0.58, p-value= 4.3e-13). Correlation analysis between the DSS of adavosertib and 633 other drugs revealed several strong positive and significant correlations. These included drugs with specific mechanisms of actions including HSP90 inhibitors (n=5), JAK2 inhibitors (n=4), topoisomerase II inhibitors (n=4), CDK4/6 inhibitors (n=3), mitotic inhibitors, vinca alkaloid microtubule depolymerizers (n=3), and PLK1 inhibitors (n=3). Since adavosertib also targets PLK1 in addition to Wee1, the correlation with PLK1 inhibitor activity confirms the similar target profiles. Based on the specific adavosertib DSS thresholds, the samples were separated in two groups. Samples sensitive to adavosertib (n=35) had DSS between 21.3 (max) and 11.9 (3rd quartile). Samples resistant to adavosertib (n=34) had DSS between 0.0 (min) and 5.65 (1st quartile). Differential gene expression analysis between the sensitive vs resistant samples showed that multiple isoforms of the PCDH and HOXB genes were upregulated in adavosertib sensitive samples. The GLI2, PI15, and SKIDA1 genes were also upregulated in the sensitive samples (Figure A). In contrast, genes such DNTT, PF4V1, TRH, CD1B, S100A16, and CD34 were overexpressed in resistant samples (Figure B). Gene set enrichment analysis revealed positive enrichment of pathways related to MYC targets v2 in the sensitive samples. On the other hand, hallmark pathways associated with cell cycle, apoptosis, RAS signaling, and p53 showed significant negative enrichment scores in the sensitive samples. No statistically significant associations were observed between drug response and frequently occuring somatic mutations in our dataset. However, genetic abberations related MLLT4-MLL/MLL-fusions were only observed in sensitive samples. Collectively, our current findings show that there may be specific gene expression signatures associated with Wee1i sensitivity such high expression of PCDH and HOXB. Also, the positive enrichment of the MYC target v2 pathway in adavosertib sensitive samples suggests that highly proliferating tumor cells might be more sensitive to Wee1i. In addition, high CD34 expression in resistant samples suggests that immature stem and progenitor cells may be less susceptible to Wee1i. In summary, targeting of Wee1 in AML - as studied in NCT05682170 azenosertib study - may be effective for a molecularly defined subset of patients.

Flavone-based dual PARP-Tubulin inhibitor manifesting efficacy against endometrial cancer

Structural tailoring of the flavone framework (position 7) via organopalladium-catalyzed C–C bond formation was attempted in this study. The impact of substituents with varied electronic effects (phenyl ring, position 2 of the benzopyran scaffold) on the antitumor properties was also assessed. Resultantly, the efforts yielded a furyl arm bearing benzopyran possessing a 4-fluoro phenyl ring (position 2) (14) that manifested a magnificent antitumor profile against the Ishikawa cell lines mediated through dual inhibition of PARP and tubulin [(IC50 (PARP1) = 74 nM, IC50 (PARP2) = 109 nM) and tubulin (IC50 = 1.4 µM)]. Further investigations confirmed the ability of 14 to induce apoptosis as well as autophagy and cause cell cycle arrest at the G2/M phase. Overall, the outcome of the study culminated in a tractable dual PARP-tubulin inhibitor endowed with an impressive activity profile against endometrial cancer.

In Vitro Induction of Polyploidy by Colchicine in the Protocorm of the Orchid Dendrobium wardianum Warner

Dendrobium wardianum is a key ornamental plant and a valuable traditional Chinese medicine. This research aimed to find the optimal protocol for in vitro inducement of polyploidy in D. wardianum by treating protocorms with colchicine (an antimitotic agent). The experiment consisted of two series of treatments. For the first treatment, the protocorms were subjected to colchicine concentrations of 25, 75, 125, 250, and 500 μM (weight/volume) for 6, 12, and 24 hours. For the second treatment, protocorms were cultivated in culture medium with colchicine (25, 75, 125, and 250 μM) for 30 days. A total of 18 polyploids were confirmed by chromosome counts and anatomical parameters. Polyploids had broad, dark green leaves with increased stem lengths compared with those of diploids. The optimal protocol for these two methods consisted of soaking in 250 μM of colchicine solution for 12 hours, resulting in inductivity of 26%, and cultivating in 75 μM for 30 days, resulting in a mutation rate of 34%. A comparison of these two protocols showed that the latter one induced more stable polyploids, but that the survival rate was slightly lower. The survival and induced mutation rates of these plants were significantly influenced by the colchicine concentration and exposure time. Higher concentrations for longer periods of time resulted in greater mortality rates and longer-lasting side effects. The protocol involving a solid medium and colchicine is worth considering. It will be intriguing to examine this methodology for the induction of stable polyploids of other orchid species.

Mitotic Dysregulation at Tumor Initiation Creates a Therapeutic Vulnerability to Combination Anti-Mitotic and Pro-Apoptotic Agents for MYCN-Driven Neuroblastoma.

MYCN amplification occurs in approximately 20-30% of neuroblastoma patients and correlates with poor prognosis. The TH-MYCN transgenic mouse model mimics the development of human high-risk neuroblastoma and provides strong evidence for the oncogenic function of MYCN. In this study, we identified mitotic dysregulation as a hallmark of tumor initiation in the pre-cancerous ganglia from TH-MYCN mice that persists through tumor progression. Single-cell quantitative-PCR of coeliac ganglia from 10-day-old TH-MYCN mice revealed overexpression of mitotic genes in a subpopulation of premalignant neuroblasts at a level similar to single cells derived from established tumors. Prophylactic treatment using antimitotic agents barasertib and vincristine significantly delayed the onset of tumor formation, reduced pre-malignant neuroblast hyperplasia, and prolonged survival in TH-MYCN mice. Analysis of human neuroblastoma tumor cohorts showed a strong correlation between dysregulated mitosis and features of MYCN amplification, such as MYC(N) transcriptional activity, poor overall survival, and other clinical predictors of aggressive disease. To explore the therapeutic potential of targeting mitotic dysregulation, we showed that genetic and chemical inhibition of mitosis led to selective cell death in neuroblastoma cell lines with MYCN over-expression. Moreover, combination therapy with antimitotic compounds and BCL2 inhibitors exploited mitotic stress induced by antimitotics and was synergistically toxic to neuroblastoma cell lines. These results collectively suggest that mitotic dysregulation is a key component of tumorigenesis in early neuroblasts, which can be inhibited by the combination of antimitotic compounds and pro-apoptotic compounds in MYCN-driven neuroblastoma.

Repositioning VU-0365114 as a novel microtubule-destabilizing agent for treating cancer and overcoming drug resistance.

Microtubule-targeting agents represent one of the most successful classes of anticancer agents. However, the development of drug resistance and the appearance of adverse effects hamper their clinical implementation. Novel microtubule-targeting agents without such limitations are urgently needed. By employing a gene expression-based drug repositioning strategy, this study identifies VU-0365114, originally synthesized as a positive allosteric modulator of human muscarinic acetylcholine receptor M5 (M5 mAChR), as a novel type of tubulin inhibitor by destabilizing microtubules. VU-0365114 exhibits a broad-spectrum in vitro anticancer activity, especially in colorectal cancer cells. A tumor xenograft study in nude mice shows that VU-0365114 slowed the in vivo colorectal tumor growth. The anticancer activity of VU-0365114 is not related to its original target, M5 mAChR. In addition, VU-0365114 does not serve as a substrate of multidrug resistance (MDR) proteins, and thus, it can overcome MDR. Furthermore, a kinome analysis shows that VU-0365114 did not exhibit other significant off-target effects. Taken together, our study suggests that VU-0365114 primarily targets microtubules, offering potential for repurposing in cancer treatment, although more studies are needed before further drug development.

Microtubule rescue control by drugs and MAPs examined with in vitro pedestal assay

Microtubules are essential cytoskeletal polymers, which exhibit stochastic transitions between assembly and disassembly, known as catastrophes and rescues. Understanding of catastrophes, rescues, and their control by drugs and microtubule associated proteins (MAPs) has been informed by in vitro reconstitutions of microtubule dynamics. In such experiments microtubules are typically observed on a flat surface of the coverslip. In contrast, we have recently proposed a modified setup in which microtubules assemble from stabilized seeds, overhanging from microfabricated pedestals, so that their dynamic extensions are fully isolated from contact with the coverslip. This assay allows to eliminate potential artifacts, which may substantially affect the frequency of microtubule rescues in vitro. Here we use the pedestal assay to study the sensitivity of microtubules to paclitaxel, one of the best-known inhibitors of microtubule dynamics. By comparing observations in the conventional and the pedestal assays, we find that microtubule dynamics are substantially more sensitive to paclitaxel when the polymers can contact the coverslip. We interpret this as a consequence of the coverslip-induced microtubule assembly perturbation, leading to formation of lattice with defects, and thereby enhancing the efficiency of paclitaxel binding to microtubules in the conventional assay. To test this idea, we use vinblastine, another small-molecule inhibitor, which had been previously shown to cause microtubule growth perturbations. We find that in the pedestal assay vinblastine sensitizes microtubules to paclitaxel to the level, observed in the conventional assay. Interestingly, a minimal fragment of MAP called CLASP2, a previously characterized rescue factor, has a strong effect on microtubule rescues, regardless of the type of assay. Overall, our study underscores the role of microtubule damage in promoting rescues and highlights the utility of the in vitro pedestal assay to study microtubule dynamics modulation by tubulin inhibitors and MAPs.

Synthesis, Anticancer Activity, and In Silico Studies of 5-(3-Bromophenyl)-N-aryl-4H-1,2,4-triazol-3-amine Analogs.

In the current study, we described the synthesis of ten new 5-(3-Bromophenyl)-N-aryl-4H-1,2,4-triazol-3-amine analogs (4a-j), as well as their characterization, anticancer activity, molecular docking studies, ADME, and toxicity prediction. The title compounds (4a-j) were prepared in three steps, starting from substituted anilines in a satisfactory yield, followed by their characterization via spectroscopic techniques. The National Cancer Institute (NCI US) protocol was followed to test the compounds' (4a-j) anticancer activity against nine panels of 58 cancer cell lines at a concentration of 10-5 M, and growth percent (GP) as well as percent growth inhibition (PGI) were calculated. Some of the compounds demonstrated significant anticancer activity against a few cancer cell lines. The CNS cancer cell line SNB-75, which showed a PGI of 41.25 percent, was discovered to be the most sensitive cancer cell line to the tested compound 4e. The mean GP of compound 4i was found to be the most promising among the series of compounds. The five cancer cell lines that were found to be the most susceptible to compound 4i were SNB-75, UO-31, CCRF-CEM, EKVX, and OVCAR-5; these five cell lines showed PGIs of 38.94, 30.14, 26.92, 26.61, and 23.12 percent, respectively, at 10-5 M. The inhibition of tubulin is one of the primary molecular targets of many anticancer agents; hence, the compounds (4a-j) were further subjected to molecular docking studies looking at the tubulin-combretastatin A-4 binding site (PDB ID: 5LYJ) of tubulin. The binding affinities were found to be efficient, ranging from -6.502 to -8.341 kcal/mol, with two major electrostatic interactions observed: H-bond and halogen bond. Ligand 4i had a binding affinity of -8.149 kcal/mol with the tubulin-combretastatin A-4 binding site and displayed a H-bond interaction with the residue Asn258. The ADME and toxicity prediction studies for each compound were carried out using SwissADME and ProTox-II software. None of the compounds' ADME predictions showed that they violated Lipinski's rule of five. All of the compounds were also predicted to have LD50 values between 440 and 500 mg/kg, putting them all in class IV toxicity, according to the toxicity prediction. The current discovery could potentially open up the opportunity for further developments in cancer.