Recent advances in hematopoietic cell kinase in cancer progression: Mechanisms and inhibitors.

Hematopoietic cell kinase (Hck), a non-receptor tyrosine kinase belonging to the Src kinase family, is intricately linked to the pathogenesis of numerous human diseases, with a particularly pronounced association with cancer. Hck not only directly impacts the proliferation, migration, and apoptosis of cancer cells but also interacts with JAK/STAT, MEK/ERK, PI3K/AKT, CXCL12/CXCR4, and other pathways. Hck also influences the tumor microenvironment to facilitate the onset and progression of cancer. This paper delves into the functional role and regulatory mechanisms of Hck in various solid tumors. Additionally, it explores the implications of Hck in hematological malignancies. The review culminates with a summary of the current research status of Hck inhibitors, the majority of which are in the pre-clinical phase of investigation. Notably, these inhibitors are predominantly utilized in the therapeutic management of leukemia, with their combinatorial potential indicating promising avenues for future research. In conclusion, this review underscores the significance of the mechanism of Hck in solid tumors. This insight is crucial for comprehending the current research trends regarding Hck: targeted therapy against Hck shows great promise in both diagnosis and treatment of malignant tumors. Further investigation into the role of Hck in cancer, coupled with the development of specific inhibitors, has the potential to revolutionize approaches to cancer treatment.

Metabolism of asparagine in the physiological state and cancer.

Asparagine, an important amino acid in mammals, is produced in several organs and is widely used for the production of other nutrients such as glucose, proteins, lipids, and nucleotides. Asparagine has also been reported to play a vital role in the development of cancer cells. Although several types of cancer cells can synthesise asparagine alone, their synthesis levels are insufficient to meet their requirements. These cells must rely on the supply of exogenous asparagine, which is why asparagine is considered a semi-essential amino acid. Therefore, nutritional inhibition by targeting asparagine is often considered as an anti-cancer strategy and has shown success in the treatment of leukaemia. However, asparagine limitation alone does not achieve an ideal therapeutic effect because of stress responses that upregulate asparagine synthase (ASNS) to meet the requirements for asparagine in cancer cells. Various cancer cells initiate different reprogramming processes in response to the deficiency of asparagine. Therefore, it is necessary to comprehensively understand the asparagine metabolism in cancers. This review primarily discusses the physiological role of asparagine and the current progress in the field of cancer research.

Immune synergistic mechanism of recombinant plasmid adjuvant containing chicken IL-4 and IL-2 fusion genes on chicken coccidia live vaccine.

The recombinant plasmid pCI-IL-4-IL-2-EGFP containing fusion genes of chicken IL-4 and IL-2 can be used as an adjuvant to enhance the anticoccidiosis effect of the chicken coccidia live vaccine. The chickens were divided into 3 groups: blank control group, vaccine + pCI-IL-4-IL-2-EGFP adjuvant coimmunization group, and vaccine-only group to investigate the immune synergy mechanism of recombinant plasmid adjuvant pCI-IL-4-IL-2-EGFP. The expressions of IL-2, IL-4, TNF-α, and IFN-γ in chicken sera and tissues were detected by ELISA and RT-qPCR, and the proliferation of T and B lymphocytes and antigen presenting cells (APC) in chicken immune organs and intestines were detected by acid alpha-naphthalase (ANAE) staining, methyl green pyronine (MGP) staining, and immunofluorescence (IF) staining, respectively. Results showed that the mRNA expression of IL-2, IL-4, IFN-γ and the number of activated T and B lymphocytes were significantly upregulated in the spleen and cecum tonsils of chickens in vaccine + pCI-IL-4-IL-2-EGFP group compared with the vaccine-only group on 7 d after vaccination (P < 0.05). Protein contents of IL-2, IL-4 and TNF-α in vaccine + pCI-IL-4-IL-2-EGFP group were significantly increased compared to vaccine-only group on 28 d of inoculation (P < 0.05). The number of T and B lymphocytes and APC in chickens of the vaccine+ pCI-IL-4-IL-2-EGFP group was significantly higher than that of the vaccine-only group in cecum tonsils, thymus and spleen after 14 and 28 d of inoculation (P < 0.05). All results revealed that pCI-IL-4-IL-2-EGFP adjuvant enhanced the immune response of chicken coccidia live vaccine by upregulating the expression of IL-2, IL-4, TNF-α, and IFN-γ and promoting the proliferation of T, B lymphocytes and APCs in chicken intestines and immune organ sites. Moreover, our study provides a theoretical basis for the clinical application of cytogenic plasmids as adjuvants.

The emerging roles of metabolism in the crosstalk between breast cancer cells and tumor-associated macrophages.

Breast cancer is the most common cancer affecting women worldwide. Investigating metabolism in breast cancer may accelerate the exploitation of new therapeutic options for immunotherapies. Metabolic reprogramming can confer breast cancer cells (BCCs) with a survival advantage in the tumor microenvironment (TME) and metabolic alterations in breast cancer, and the corresponding metabolic byproducts can affect the function of tumor-associated macrophages (TAMs). Additionally, TAMs undergo metabolic reprogramming in response to signals present in the TME, which can affect their function and breast cancer progression. Here, we review the metabolic crosstalk between BCCs and TAMs in terms of glucose, lipids, amino acids, iron, and adenosine metabolism. Summaries of inhibitors that target metabolism-related processes in BCCs or TAMs within breast cancer have also served as valuable inspiration for novel therapeutic approaches in the fight against this disease. This review provides new perspectives on targeted anticancer therapies for breast cancer that combine immunity with metabolism.

FUNDC2, a mitochondrial outer membrane protein, mediates triple-negative breast cancer progression via the AKT/GSK3ß/GLI1 pathway.

Triple-negative breast cancer (TNBC) lacks effective therapeutic targets and has a poor prognosis, easy recurrence and metastasis. It is urgent and important to explore TNBC treatment targets. Through mass spectrometry combined with qRT-PCR validation in luminal A cells and TNBC cells, high-content screening and clinical sample analysis, FUNDC2 was discovered as a novel target. The function of the outer mitochondrial membrane protein FUNDC2 in breast cancer is still unclear. In this study, we find that FUNDC2 expression in TNBC tissues is significantly higher than that in luminal subtype breast cancer tissues. FUNDC2 silencing in TNBC cells significantly reduces cell proliferation, migration and invasion. As demonstrated in vivo using subcutaneous tumor xenografts in mice, FUNDC2 suppression significantly inhibits tumor growth. The underlying mechanism might be mediated by inactivating its downstream signal AKT/GSK3ß and GLI1, a key factor of the Hedgehog signaling pathway. Therefore, FUNDC2 may promote TNBC progression and provide a therapeutic target for treating TNBC.

Inhibitory effect of the novel tyrosine kinase inhibitor DCC-2036 on triple-negative breast cancer stem cells through AXL-KLF5 positive feedback loop.

Triple-negative breast cancer (TNBC), an aggressive histological subtype of breast cancer, exhibits a high risk of early recurrence rate and a poor prognosis, and it is primarily associated with the abundance of cancer stem cells (CSCs). At present, the strategies for effectively eradicating or inhibiting TNBC CSCs are still limited, which makes the development of novel drugs with anti-CSCs function be of great value for the treatment of TNBC, especially the refractory TNBC. In this study, we found that the small-molecule tyrosine kinase inhibitor DCC-2036 suppressed TNBC stem cells by inhibiting the tyrosine kinase AXL and the transcription factor KLF5. DCC-2036 downregulated the expression of KLF5 by decreasing the protein stability of KLF5 via the AXL-Akt-GSK3ß signal axis, and in turn, the downregulation of KLF5 further reduced the expression of AXL via binding to its promotor (-171 to -162 bp). In addition, p-AXL/AXL levels were positively correlated with KLF5 expression in human TNBC specimens. These findings indicated that DCC-2036 is able to suppress the CSCs in TNBC by targeting the AXL-KLF5 positive feedback loop. Moreover, our findings indicated that DCC-2036 increased the sensitivity of TNBC chemotherapy. Therefore, this study proposes a potential drug candidate and several targets for the treatment of refractory TNBC.

The interaction between free Ca2+ in host cells and invasion of E. tenella.

Eimeria tenella is the most pathogenic and common coccidia that causes chicken coccidiosis. The intracellular free Ca2+ of the host cell is closely related to the invasion, development, and proliferation of intracellular parasites. To determine the dynamic changes of intracellular free Ca2+ and its function in the process of E. tenella invading host cells, we established a chick embryo cecal epithelial cells model of E. tenella infection. Chick embryo cecal epithelial cells were treated with different Ca2+ signal inhibitor, respectively, and then infected with E. tenella. The results showed that extracellular Ca2+, Ca2+ channels on the cell membrane, IP3R ion channels on the endoplasmic reticulum membrane, and RyR ion channels regulated the free Ca2+ in cecal epithelial cells. Through fluorescence labeling and invasion rate detection, we found that the intracellular Ca2+ did not change significantly during the invasion of E. tenella, but its stability was critical to the invasion of parasites.

Identification of an AXL kinase inhibitor in triple-negative breast cancer by structure-based virtual screening and bioactivity test.

Breast cancer is a malignant tumor that occurs in the glandular epithelium of the breast, and more than 15% of the patients are triple-negative breast cancer (TNBC). Therefore, finding new targets and targeted therapeutic drugs for TNBC is urgent. Overexpression of the AXL is associated with motility and invasiveness of the TNBC cells, which is a potential target for breast cancer therapy. A compound Y041-5921 (IC50  = 6.069 µm for AXL kinase and IC50  = 4.1 µm for MDA-MB-231 cell line) was identified through structure-based virtual screening and bioassay test for the first time. The compound Y041-5921 could significantly inhibit the proliferation and invasion of the TNBC cells and the toxicity of Y041-5921 to normal immortalized breast epithelial cells was far lower than that of commonly used clinical chemotherapy drugs. Besides, it also had well inhibitory effect on the proliferation of many other malignant tumor cell lines (the IC50  value are 10.0 m, 7.1 m, 10.3 m, 11.4 m and 5.8 m for U251 cell, COLO cell, PC-9 cell, CAKI-1 cell and MG63 cell, respectively). The interaction mechanism between Y041-5921 and AXL was studied by molecular dynamics (MD) simulations and binding free energy calculation, and the key residues whose energy contribution mainly comes from non-polar solvation interaction (such as Ala565, Lys567, Met598, Leu620, Pro621, Met623, Lys624, Arg676, Asn677 and Met679) were identified. The small molecule inhibitors Y041-5921 targeting AXL reported in this work will lay a foundation and provide a theoretical basis for the development of the TNBC.

Tumor-Associated Macrophages: Critical Players in Drug Resistance of Breast Cancer.

Drug resistance is one of the most critical challenges in breast cancer (BC) treatment. The occurrence and development of drug resistance are closely related to the tumor immune microenvironment (TIME). Tumor-associated macrophages (TAMs), the most important immune cells in TIME, are essential for drug resistance in BC treatment. In this article, we summarize the effects of TAMs on the resistance of various drugs in endocrine therapy, chemotherapy, targeted therapy, and immunotherapy, and their underlying mechanisms. Based on the current overview of the key role of TAMs in drug resistance, we discuss the potential possibility for targeting TAMs to reduce drug resistance in BC treatment, By inhibiting the recruitment of TAMs, depleting the number of TAMs, regulating the polarization of TAMs and enhancing the phagocytosis of TAMs. Evidences in our review support it is important to develop novel therapeutic strategies to target TAMs in BC to overcome the treatment of resistance.

Knockdown of ZBTB7A inhibits cell proliferation of breast cancer through regulating the ubiquitination of estrogen receptor alpha.

AIMS: ZBTB7A, a transcriptional repressor, accelerates the breast cancer progression. Over 70% of breast cancer samples are identified as ER-α positive. Due to the function of ZBTB7A in ER-α positive breast cancer incompletely known, we aimed to determine the role of ZBTB7A in ER-α positive cancer and explore the underlying mechanisms. MAIN METHODS: In this study, the correlation between ZBTB7A and ER-α was confirmed by tissue microarray-based and TCGA database. Then, we explore if ZBTB7A maintains ER-α's level via targeting ER-α's expression or degradation. Finally, we examined the effect of ZBTB7A on the proliferation of breast cancer cells. KEY FINDINGS: We further confirmed that ZBTB7A shows a significant positive correlation with ER-α in clinical breast cancer samples by tissue microarray-based analysis. Mechanically, we identified that the inhibition of ZBTB7A could upregulate E3 ligase TRIM25 leading to enhancement of ER-α ubiquitination and proteasomal degradation, which could partly explain the correlation between ZBTB7A and ER-α. Besides, we uncovered that ZBTB7A could also transcriptionally increase the expression of ER-α via indirectly binding to the region +146 to +461 bp downstream of the transcription start site of ESR1 (ERpro315) in breast cancer cells. Furthermore, ZBTB7A is found to stimulate the expression of ER-α's downstream genes, and promote the growth of estrogen receptor alpha (ER-α)-positive breast cancer cells. SIGNIFICANCE: Our data revealed the novel mechanisms through which ZBTB7A manipulates ER-α level and might provide a new avenue for endocrine therapy in breast cancer.

[Construction of lentiviral vector for mouse CXC chemokine receptor 4 gene and its expression in eukaryotic cells].

This study was aimed to clone the gene coding mouse CXC chemokine receptor 4 (CXCR4), to construct the recombinant lentiviral vector carrying enhanced green fluorescence protein (EGFP) and to explore its expression in eukaryotic cells (293FT cells). The full length CXCR4 gene was cloned by RT-PCR using bone marrow cells from C57BL/6 mouse as template and inserted into PCR-Blunt vector. CXCR4 fragment was generated by digestion with restriction endonuclease and subcloned into a lentiviral vector to generate recombinant lentiviral vector LV-IRES-EGFP-CXCR4, which was co-transfected into 293FT cells together with envelope plasmid and packaging plasmid by lipofectamine 2000. Viruses were gathered and concentrated using ultracentrifuge, and then transfected into 293FT cells. Expression of EGFP was detected by fluorescent microscopy and flow cytometry (FCM). And the expression of CXCR4 protein was detected by Western blot. The results demonstrated that mouse CXCR4 gene was cloned and the lentiviral vector was successfully constructed. The lentiviral particles were correctly packaged, and the virus titers were above 10(8) TU/ml in the supernatant after concentration. Expression of EGFP was detected by fluorescent microscopy in the transfected 293FT cells, and the transfection efficacy > 95% was determined by FCM. Expression of CXCR4 protein detected by FCM and Western blot was significantly higher than that in control group. It is concluded that the CXCR4 gene along with the gene coding EGFP is successfully inserted into a lentiviral vector to construct a recombinant lentiviral vector, which can be expressed in eukaryotic cells.

{µ-6,6'-Dimeth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-idyne)]diphenolato}-µ-nitrato-dinitratoterbium(III)zinc(II).

In the title heteronuclear Zn(II)-Tb(III) complex (systematic name: {6,6'-dimeth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-id-yne)]diphenolato-1κ(4)O(6),O(1),O(1'),O(6')}:2κ(4)O(1),N,N',O(1')-µ-nitrato-1:2κ(2)O:O'-dinitrato-1κ(4)O,O'-terbium(III)zinc(II)), [TbZn(C(18)H(18)N(2)O(4))(NO(3))(3)], with the hexa-dentate Schiff base compartmental ligand N,N'-bis-(3-methoxy-salicyl-idene)ethyl-enediamine (H(2)L), the Tb and Zn atoms are triply bridged by two phenolate O atoms of the Schiff base ligand and one nitrate ion. The five-coordinate Zn atom is in a square-pyramidal geometry with the donor centers of two imine N atoms, two phenolate O atoms and one of the bridging nitrate O atoms. The Tb(III) center has a ninefold coordination environment of O atoms, involving the phenolate O atoms, two meth-oxy O atoms, two O atoms from two nitrate ions and one from the bridging nitrate ion. Weak inter-molecular C-H⋯O inter-actions generate a two-dimensional layer structure.