Amivantamab: a monoclonal EGFR-MET bispecific antibody for EGFR exon 20 insertion in non-small cell lung cancer.

The U.S. Food and Drug Administration (FDA) first approved amivantamab, a monoclonal epidermal growth factor receptor (EGFR)-mesenchymal--epithelial transition factor (MET) bispecific antibody, in May 2021, to treat adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with an insertion mutation in exon 20 of EGFR. The approval of amivantamab represents a targeted therapy for this subtype of advanced NSCLC. In contrast to other drugs that inhibit the tyrosine kinase activity in the protein, EGFR, amivantamab has efficacy in inhibiting EGFR and MET. In this article, we summarize the development of therapeutic drugs for NSCLC, discuss the mechanism of action of amivantamab, review data from clinical trials with amivantamab and suggest future lines of research.

Upregulation of miR-33 Exacerbates Heat-Stress-Induced Apoptosis in Granulosa Cell and Follicular Atresia of Nile Tilapia (Oreochromis niloticus) by Targeting TGFß1I1.

High temperature affects egg quality and increases follicular atresia in teleosts. The present study aimed to explore the regulated mechanism of ovary syndrome of Nile tilapia (Oreochromis niloticus) exposed to heat stress. To this end, we conducted histological and biochemical analyses and integrated miRNA-target gene analyses. The histochemical analyses confirmed that heat stress promoted the apoptosis of granulosa cell and therefore resulted in increased follicular atresia in the ovary. Heat stress led to the differential expression of multiple miRNAs (miR-27e, -27b-3p, -33, -34a -133a-5p, and -301b-5p). In a luciferase activity assay, miR-33 bound to the 3'-untranslated region (UTR) of the TGFß1I1 (transforming growth factor-ß1-induced transcript 1) gene and inhibited its expression. A TGFß1I1 gene signal was detected in the granulosa cells of Nile tilapia by immunohistochemical analysis. Up-regulation of the miR-33 of tilapia at 6 d and 12 d exposed to heat (34.5 °C ± 0.5 °C) had significant down-regulation of the TGFß1I1 expression of the gene and protein in tilapia ovaries. An miRNA-target gene integrated analysis revealed that miR-33 and TGFß1I1 function in an apoptosis-related signal pathway. The signal transduction of the vascular endothelial growth factor (VEGF) family members VEGFA and its receptor (KDR) in the heat-stressed group decreased significantly compared with the control group. Transcript-levels of the Bax and Caspase-3 as apoptotic promotors were activated and Bcl-2 and Caspase-8 as apoptotic inhibitors were suppressed in the heat-stressed tilapia. These results suggest that heat stress increases the expression of miR-33, which targets TGFß1I1 and inhibits its expression, resulting in decreased levels of follicle-stimulating hormone and 17ß-estradiol and increased apoptosis by suppressing VEGF signaling, eventually inducing follicular atresia. In conclusion, our results show that the miR-33/TGFß1I1 axis of Nile tilapia is involved in the follicular development of broodstock, and can suppress VEGF signaling to accelerate follicular atresia. Our findings demonstrate the suppressive role of miR-33 during oocyte development in Nile tilapia.

Asparaginase Erwinia chrysanthemi for acute lymphoblastic leukemia and lymphoblastic lymphoma.

Acute lymphoblastic leukemia (ALL) is a neoplastic disease characterized by the malignant proliferation of lymphoid cells in the blood and bone marrow. It accounts for approximately 75% of childhood leukemia. Lymphoblastic lymphoma (LBL) is a type of non-Hodgkin's lymphoma characterized by rapid growth and highly aggressive characteristics that occurs most commonly in adolescents and young adults. Asparaginase is primarily used to treat patients with ALL or LBL. Because allergic reactions occur in patients treated with bacterial-derived asparaginase, it is important to develop an alternative asparaginase preparation for patients allergic to asparaginase. Recombinant asparaginase Erwinia chrysanthemi-rywn (JZP-458) is a recombinant Erwinia asparaginase that uses a novel Pseudomonas fluorescens expression platform in the production process. JZP-458 has the same amino acid sequence as E. chrysanthemi-derived asparaginase (ERW) and its in vitro activity is similar to that of ERW. JZP-458 is highly efficacious in patients allergic to asparaginase. Data from a phase I clinical trial indicated that following the intramuscular or intravenous administration of JZP-458 to volunteers, serum asparaginase activity ≥ 0.1 IU/mL was observed in 100% of the volunteers 72 hours after administration. In this review, we summarize the mechanism of action and the related research data obtained with JZP-458 for the treatment of ALL or LBL.

Reprogramming the tumor microenvironment by genome editing for precision cancer therapy.

The tumor microenvironment (TME) is essential for immune escape by tumor cells. It plays essential roles in tumor development and metastasis. The clinical outcomes of tumors are often closely related to individual differences in the patient TME. Therefore, reprogramming TME cells and their intercellular communication is an attractive and promising strategy for cancer therapy. TME cells consist of immune and nonimmune cells. These cells need to be manipulated precisely and safely to improve cancer therapy. Furthermore, it is encouraging that this field has rapidly developed in recent years with the advent and development of gene editing technologies. In this review, we briefly introduce gene editing technologies and systematically summarize their applications in the TME for precision cancer therapy, including the reprogramming of TME cells and their intercellular communication. TME cell reprogramming can regulate cell differentiation, proliferation, and function. Moreover, reprogramming the intercellular communication of TME cells can optimize immune infiltration and the specific recognition of tumor cells by immune cells. Thus, gene editing will pave the way for further breakthroughs in precision cancer therapy.

Pacritinib for myelofibrosis in adults with thrombocytopenia.

Myelofibrosis is a rare progressive cancer of the bone marrow that disrupts the normal production of healthy blood cells, leading to bone marrow failure. Patients with myelofibrosis and severe thrombocytopenia (platelet count below 50 × 109/L) have a wide range of unmet medical needs compared with those without thrombocytopenia. Usually, these patients have an increased disease burden, increased transfusion dependence, shorter overall survival, and limited treatment options. Pacritinib is a new oral kinase inhibitor specifically targeting Janus kinase 2 (JAK2), interleukin-1 receptor-associated kinase 1 (IRAK-1) and colony-stimulating factor 1 receptor (CSF-1R), and is indicated for the treatment of adults with moderate or high risk of primary or secondary myelofibrosis (post-polycythemia or post-primary thrombocytopenia) whose platelet count is less than 50 × 109/L. In this review, we introduce pacritinib and make a brief comparison of different JAK inhibitors in clinical application.

Therapeutic immune monitoring of CD4+CD25+ T cells in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors.

Tyrosine kinase inhibitors (TKIs), including imatinib, dasatinib and nilotinib, are effective forms of therapy for various types of solid cancers and Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia. A number of TKIs have been known to have strong effects on T cells, particularly cluster of differentiation (CD) 4+CD25+ T cells, also known as regulatory T cells (Tregs). There is currently a deficit in the available clinical data regarding this area of study. In the present study, a total of 108 peripheral blood samples were collected from patients with chronic myeloid leukemia (CML) at diagnosis (n=31), and at 3 and 6 months following treatment with TKI [imatinib (n=12), dasatinib (n=11) and nilotinib groups (n=8)] and healthy controls (n=15). Peripheral blood mononuclear cells were collected from the patients prior to and following TKI treatment. The subtype and number of T lymphocytes in patients and healthy donors were analyzed using flow cytometry. Additionally, flow cytometry and ELISA were used to detect the proliferation and suppression of Tregs. Expression of cytokines and other molecules [forkhead box P3 (FOXP3), glucocorticoid-induced tumor necrosis factor receptor (GITR) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4)] were also analyzed at 3 and 6 months following treatment with TKIs. It was indicated that, at diagnosis, a similar number of lymphocytes were detected in patients and control. However, following treatment with a TKI, the number of total T cells, Tregs, CD4+ T and CD8+ T cells decreased to various degrees in patients. Furthermore, the decrease in the number of Tregs was more significant with time. Although treatment with imatinib, dasatinib and nilotinib demonstrated similar inhibitory effects on the quantity of Tregs in vivo, the TKIs exhibited differential effects on the function of Tregs in vitro. Proliferation, suppression and expression of cytokines [interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-ß] and molecules (FOXP3, GITR and CTLA-4) decreased significantly in treatment groups with imatinib and dasatinib. The decrease was not significant in the nilotinib treatment group. Imatinib and dasatinib may exert more marked inhibitory roles compared with nilotinib on regulating the number and function of Tregs. These results suggest that personalized treatment and follow-up of CML patients during TKI treatment, particularly for those who received post-transplant TKI treatment may be beneficial.

CDKN2 Gene Deletion as Poor Prognosis Predictor Involved in the Progression of Adult B-Lineage Acute Lymphoblastic Leukemia Patients.

Deletion of cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) is well known in many hematologic malignancies, but only few reports have investigated this deletion effect on clinical prognosis. This study performed analysis of the CDKN2 deletion in 215 adult B- lineage acute lymphoblastic leukemia (B-ALL) patients, and related cytogenetic prognostic factors (BCR/ABL; E2A/PBXl; TEL/AML1; Mixed Lineage Leukemia (MLL) rearrangement; MYC, Immunoglobulin heavy locus (IGH) translocation). The prevalence of CDKN2 deletions in all study populations was 28.4%. There is no difference between patients with CDKN2 deletion and wild-type patients in sex, age, white blood cells (WBC) count, BM blast percentage, extra infiltration and induction complete remission (CR) rate. Analysis in relapse patients revealed that the distribution of CDKN2 deletion is higher in relapse patients (44.6%) than all patients (28.4%, P=0.006). Deletion of CDKN2 was significantly associated with poor outcomes including decreased overall survival (OS) (P<0.001), lower disease free-survival (DFS) (P<0.001), and increased cumulative incidence of relapse (P=0.002); Also, CDKN2 deletion was strongly associated with IGH translocation (P=0.021); and had an adverse effect on patients with BCR-ABL fusion gene or with MLL rearrangement. Patients with CDKN2 gene deletion benefited from allogenic hematopoietic stem cell transplantation (Allo-HSCT). Deletion of CDKN2 gene was commonly observed through leukemia progression and was poor prognostic marker in long-term outcomes.

Prognostic Significance of Monosomal Karyotype in Adult Patients With Acute Myeloid Leukemia Treated With Risk-Adapted Protocols.

BACKGROUND: The monosomal karyotype (MK) is a well-known adverse prognostic factor and has been found to be related to poor outcome in patients with acute myeloid leukemia (AML). However, the outcome in MK-positive AML patients undergoing different therapies has not been well investigated. PATIENTS AND METHODS: We retrospectively analyzed clinical and laboratory features in 225 MK-positive AML patients. Clinical outcome of overall survival (OS) and disease-free survival (DFS) was evaluated in patients according to age group and in patients who received different therapy protocols. RESULTS: The proportion of MK-positive patients increased along with age. Also, patients who were treated with high-dose cytarabine (HD-Ara-C) as consolidation therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) demonstrated longer OS and DFS compared to allo-HSCT or HD-Ara-C alone. Patients treated with allo-HSCT alone exhibited longer DFS compared to patients treated with HD-Ara-C alone. No difference in OS was discovered between these 2 single protocols. CONCLUSION: MK was associated with a lower complete remission rate. HD-Ara-C therapy followed by allo-HSCT could improve the prognosis of MK-positive AML patients.

A comparative proteomic study of Homoharringtonine-induced apoptosis in leukemia K562 cells.

The objective of this study was to determine the changes in protein profiles of K562 chronic myeloid leukemia (CML) cells in response to Homoharringtonine (HHT). HHT treatment significantly increased apoptosis of K562 cells. Proteomic analyses indicated 32 differentially expressed proteins, 13 of which were identified by mass spectrometry (nine down-regulated and four up-regulated). Aside from alterations in apoptotic proteins and proteins associated with transcription and translation, our data also revealed changes in oxidative stress response and redox reaction-related proteins, such as heat shock proteins (Hsps), DJ-1 and thioredoxin. Specifically, these proteins were validated to decrease after HHT treatment in K562 cells and in primary CML cells by immunoblot analysis. Additionally, Hsps, DJ-1 and thioredoxin, which were also shown to decrease in primary cells from imatinib-resistant patients, may be promising potential targets for mechanistic research and new clinical treatments.

[Treatment efficacy of imatinib mesylate versus allogeneic hematopoietic stem cell transplantation for patients with chronic myeloid leukemia in chronic phase].

OBJECTIVE: To compare the treatment efficacy of imatinib mesylate versus allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with chronic myeloid leukemia in chronic phase. METHODS: The efficacy, overall survival, progression-free survival and adverse events were evaluated in 198 patients on these two therapies from February 2002 to December 2012 at our hospital. One hundred and fifteen cases in imatinib group (n = 115) received imatinib at an initial daily dose of 400 mg and then dose was adjusted according to blood routine test and therapy response. All patients were evaluated for hematologic, cytogenetic and molecular responses every 1-3 months. The allo-HSCT group (n = 83) received myeloablative preconditioning regimen and methotrexate (MTX) and cyclosporine A (CsA) were used for graft-versus-host disease (GVHD) partially plus mycophenolate mofetil (MMF) and antihuman thymocyte globulin (ATG). The engraftment evidence and evolution of cytogenetic and molecular response was conventionally detected after allo-HSCT. RESULTS: In imatinib group, 59 of 86 (68.6%) cases achieved complete cytogenetic response (CCyR) in the 12 months after therapy, while 67 of 70 (95.7%) cases achieved CCyR in allo-HSCT group. The relapse rates of two groups were 14.8% (17/115) , 12.3% (10/81) respectively. The adverse reaction of imatinib in imatinib group was obviously much more tolerable for patients compared with frequently occurred GVHD and infection in allo-HSCT group. The 10-year cumulative overall survival (OS) rate was 93.9% in imatinib group and 77.1% in allo-HSCT group (P = 0.015). And the 10-year cumulative progression-free survival (PFS) rate was 86.1% in imatinib group versus 88.0% in allo-HSCT group (P = 0.508) . For Sokal rating stratified analysis, the cumulative OS rates of two groups were 96.4% and 68.0% (P = 0.049) for intermediate-risk patients, 92.6% and 57.1% (P = 0.017) for high-risk patients while the cumulative PFS rates of two groups were 89.3% and 88.0% for intermediate-risk patients (P = 0.942), 70.4% and 85.7% for high-risk patients (P = 0.405). The rates of OS and PFS were not significantly different for low-risk patients. The cumulative OS rates of two groups were 94.7% and 73.5% (P = 0.009) for those ≥ 30 years old and the cumulative PFS rates of two groups 84.2% and 94.1% respectively (P = 0.147). CONCLUSION: Imatinib mesylate is superior to allo-HSCT for patients with chronic myeloid leukemia in chronic phase.

The phosphodiesterase-5 inhibitor vardenafil is a potent inhibitor of ABCB1/P-glycoprotein transporter.

One of the major causes of chemotherapy failure in cancer treatment is multidrug resistance (MDR) which is mediated by the ABCB1/P-glycoprotein. Previously, through the use of an extensive screening process, we found that vardenafil, a phosphodiesterase 5 (PDE-5) inhibitor significantly reverses MDR in ABCB1 overexpressing cancer cells, and its efficacy was greater than that of tadalafil, another PDE-5 inhibitor. The present study was designed to determine the reversal mechanisms of vardenafil and tadalafil on ABC transporters-mediated MDR. Vardenafil or tadalafil alone, at concentrations up to 20 µM, had no significant toxic effects on any of the cell lines used in this study, regardless of their membrane transporter status. However, vardenafil when used in combination with anticancer substrates of ABCB1, significantly potentiated their cytotoxicity in ABCB1 overexpressing cells in a concentration-dependent manner, and this effect was greater than that of tadalafil. The sensitivity of the parenteral cell lines to cytotoxic anticancer drugs was not significantly altered by vardenafil. The differential effects of vardenafil and tadalafil appear to be specific for the ABCB1 transporter as both vardenafil and tadalafil had no significant effect on the reversal of drug resistance conferred by ABCC1 (MRP1) and ABCG2 (BCRP) transporters. Vardenafil significantly increased the intracellular accumulation of [(3)H]-paclitaxel in the ABCB1 overexpressing KB-C2 cells. In addition, vardenafil significantly stimulated the ATPase activity of ABCB1 and inhibited the photolabeling of ABCB1 with [(125)I]-IAAP. Furthermore, Western blot analysis indicated the incubation of cells with either vardenafil or tadalafil for 72 h did not alter ABCB1 protein expression. Overall, our results suggest that vardenafil reverses ABCB1-mediated MDR by directly blocking the drug efflux function of ABCB1.