Harnessing the potential of long non-coding RNAs in breast cancer: from etiology to treatment resistance and clinical applications.

Breast cancer (BC) is the most common malignancy among women and a leading cause of cancer-related deaths of females worldwide. It is a complex and molecularly heterogeneous disease, with various subtypes that require different treatment strategies. Despite advances in high-resolution single-cell and multinomial technologies, distant metastasis and therapeutic resistance remain major challenges for BC treatment. Long non-coding RNAs (lncRNAs) are non-coding RNAs with more than 200 nucleotides in length. They act as competing endogenous RNAs (ceRNAs) to regulate post-transcriptional gene stability and modulate protein-protein, protein-DNA, and protein-RNA interactions to regulate various biological processes. Emerging evidence suggests that lncRNAs play essential roles in human cancers, including BC. In this review, we focus on the roles and mechanisms of lncRNAs in BC progression, metastasis, and treatment resistance, and discuss their potential value as therapeutic targets. Specifically, we summarize how lncRNAs are involved in the initiation and progression of BC, as well as their roles in metastasis and the development of therapeutic resistance. We also recapitulate the potential of lncRNAs as diagnostic biomarkers and discuss their potential use in personalized medicine. Finally, we provide lncRNA-based strategies to promote the prognosis of breast cancer patients in clinical settings, including the development of novel lncRNA-targeted therapies.

Phytochemical-Based Study of Ethanolic Extract of Saraca asoca in Letrozole-Induced Polycystic Ovarian Syndrome in Female Adult Rats.

Polycystic ovarian syndrome (PCOS) is a complex metabolic and endocrine disorder which affects women of reproductive age. It is a condition in which ovaries produce an excessive amount of androgen (the male sex hormone). Saraca asoca (Roxb.) Willd. is a plant of the Fabaceae family. This plant has been traditionally used as a uterine tonic in leucorrhea and dysmenorrhea due to its various pharmacological activities. In this study, the ethanolic extract of S. asoca (EESA) was evaluated for its potential to be used for the management of PCOS. HPLC analysis revealed the presence of various phytoconstituents: kaempferol, rutin, (-)-epicatechin, salicylic acid, and gallic acid. For PCOS induction, 30 adult female rats were randomly divided into two groups: the control group (n = 5) and the PCOS group (n = 25). Letrozole (1 mg/kg/day) was administered per orally (p.o.) for a period of 7 weeks for the induction of disease. Weekly body weight measurements and daily vaginal cytology examinations were performed for disease confirmation. After disease induction, the PCOS group was further divided into five groups (n = 5), that is, disease control, metformin, and EESA (200, 400, and 600 mg/kg) groups, respectively, and given treatment doses for next 5 weeks. After the treatment period, all animals were weighed and euthanized humanly. Blood samples were collected for hormonal assays, lipid profiles, and liver function tests. For histological assessment of ovarian cysts, ovaries were dissected. Livers were preserved to evaluate EESA's antioxidant properties. Histopathology analysis revealed that EESA reduced body weight and the number of cystic follicles. Furthermore, it also lowered the elevated levels of serum testosterone, luteinizing hormone, insulin, and malonaldehyde in PCOS rats while increasing the levels of follicle-stimulating hormone, estradiol, progesterone, prolactin, and other antioxidant enzymes such as superoxide dismutase, glutathione, and catalase. It can be concluded that EESA exhibited beneficial effects in normalizing the perturbed hormonal profile and improved the ovary status by decreasing the cystic follicle and improving the ovulation status in a dose-dependent manner.

Trends in prescription therapy for adolescents with depression in nine major areas of China during 2017-2021.

Objective: To date, no national-scale drug usage survey for adolescents with depression has been conducted in China, and the purpose of this study was to examine the national trends in prescriptions in Chinese adolescent depression patients from 2017 to 2021. Methods: Prescribing data were extracted from the Hospital Prescription Analysis Cooperative Project. The average number of patients per year, the cost of treatment, and the prescription patterns (monotherapy vs. combination therapy) were analyzed, and subgroup analyses were conducted depending on age, sex, and drug class. Results: The study included 674,099 patients from 136 hospitals located in nine major areas of China. Of all patients, the proportion of adolescents increased from 1.63% in 2017 to 6.75% in 2021. Visits by adolescent depression patients increased from 1,973 in 2017 to 9,751 in 2021, and the corresponding cost increased from 607,598 Chinese Yuan in 2017 to 2,228,884 Chinese Yuan in 2021. The incidence of adolescent depression among female individuals was far beyond that among male individuals. Combination therapy was more frequent than monotherapy, and the most commonly prescribed drugs were antidepressants, antipsychotics, antiepileptics, and antianxietics. Despite the use of sertraline decreasing from 47.90 to 43.39%, it was the most frequently used drug. Conclusion: In summary, the prescriptions and cost of treatment for adolescent depression patients both increased rapidly. The widespread use of those drugs with weak clinical evidence reflects the current state of China, which should arouse our attention. The study can provide references for clinical treatment decisions and a basis for more efficient allocation of healthcare resources by the government.

Efficacy and safety of broad spectrum penicillin with or without beta-lactamase inhibitors vs first and second generation cephalosporins as prophylactic antibiotics during cesarean section: a systematic review and meta-analysis.

This study assessed the efficacy and safety between broad spectrum penicillin (P2) with or without beta-lactamase inhibitors (P2+) versus first and second generation cephalosporins (C1&C2) in the prevention of post-cesarean infections. Relevant randomized controlled trials (RCTs) were searched in English and Chinese databases: nine RCTs were involved. Six trials compared P2+ vs C1&C2, no differences were found between interventions for endometritis, wound infection, urinary tract infection, febrile morbidity and maternal rashes. Four trials compared P2 vs C1&C2, no differences were found between interventions for endometritis, febrile morbidity, wound infection and urinary tract infection. Postoperative hospitalization was longer for women in P2 than C1&C2. Based on these results, P2/P2+ and C1&C2 may have similar efficacy on postoperative infections after cesarean section, there is no data on infant outcomes. PROSPERO Registration Number: CRD42022345721.

Cell membrane-camouflaged PLGA biomimetic system for diverse biomedical application.

The emerging cell membrane (CM)-camouflaged poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) (CM@PLGA NPs) have witnessed tremendous developments since coming to the limelight. Donning a novel membrane coat on traditional PLGA carriers enables combining the strengths of PLGA with cell-like behavior, including inherently interacting with the surrounding environment. Thereby, the in vivo defects of PLGA (such as drug leakage and poor specific distribution) can be overcome, its therapeutic potential can be amplified, and additional novel functions beyond drug delivery can be conferred. To elucidate the development and promote the clinical transformation of CM@PLGA NPs, the commonly used anucleate and eukaryotic CMs have been described first. Then, CM engineering strategies, such as genetic and nongenetic engineering methods and hybrid membrane technology, have been discussed. The reviewed CM engineering technologies are expected to enrich the functions of CM@PLGA for diverse therapeutic purposes. Third, this article highlights the therapeutic and diagnostic applications and action mechanisms of PLGA biomimetic systems for cancer, cardiovascular diseases, virus infection, and eye diseases. Finally, future expectations and challenges are spotlighted in the concept of translational medicine.

DEC1 negatively regulates CYP2B6 expression by binding to the CYP2B6 promoter region ascribed to IL-6-induced downregulation of CYP2B6 expression in HeLa cells.

The cytochrome P450 superfamily (CYPs) is a group of metabolic enzymes involved in drug biotransformation/metabolism. It is the most important drug metabolic enzyme; however, its mechanism of action remains unclear.We investigated the expression of CYP2B6 in HeLa cells induced by interleukin-6 (IL-6) and explored the relationship between differentially expressed chondrocytes 1 (DEC1) and CYP2B6 via luciferase reporter, chromatin immunoprecipitation (ChIP) and ELISA assays.We observed the expression of CYP2B6 in HeLa cells exhibited a time-dependent decrease under the effect of IL-6, and the expression of CYP2B6 down-regulated by IL-6was negatively correlated with DEC1. After overexpression or knockdown of DEC1 in HeLa cells, the expression of CYP2B6 decreased or increased. The luciferase reporter assay and ChIP assay confirmed that DEC1 inhibited the expression of CYP2B6 by binding to the CYP2B6 promoter. ELISA results showed that high expression of DEC1 or low expression of CYP2B6 can promote the secretion of IL-6 in HeLa cells, and the secreted IL-6 can continually downregulate the expression of CYP2B6 in HeLa cells.Our results indicate that DEC1/CYP2B6 pathway in the inflammatory environment of tumours, and this provides a small amount of theoretical basis for the study of genes encoding drug-metabolising enzymes.

Hyperthermia Selectively Destabilizes Oncogenic Fusion Proteins.

The PML/RARα fusion protein is the oncogenic driver in acute promyelocytic leukemia (APL). Although most APL cases are cured by PML/RARα-targeting therapy, relapse and resistance can occur due to drug-resistant mutations. Here we report that thermal stress destabilizes the PML/RARα protein, including clinically identified drug-resistant mutants. AML1/ETO and TEL/AML1 oncofusions show similar heat shock susceptibility. Mechanistically, mild hyperthermia stimulates aggregation of PML/RARα in complex with nuclear receptor corepressors leading to ubiquitin-mediated degradation via the SIAH2 E3 ligase. Hyperthermia and arsenic therapy destabilize PML/RARα via distinct mechanisms and are synergistic in primary patient samples and in vivo, including three refractory APL cases. Collectively, our results suggest that by taking advantage of a biophysical vulnerability of PML/RARα, thermal therapy may improve prognosis in drug-resistant or otherwise refractory APL. These findings serve as a paradigm for therapeutic targeting of fusion oncoprotein-associated cancers by hyperthermia. SIGNIFICANCE: Hyperthermia destabilizes oncofusion proteins including PML/RARα and acts synergistically with standard arsenic therapy in relapsed and refractory APL. The results open up the possibility that heat shock sensitivity may be an easily targetable vulnerability of oncofusion-driven cancers.See related commentary by Wu et al., p. 300.

Involvement of PML-I in reformation of PML nuclear bodies in acute promyelocytic leukemia cells by leptomycin B.

Acute promyelocytic leukemia (APL) is characterized by a reciprocal translocation between chromosomes 15 and 17, t(15;17), resulting in the expression of PML-RARα fusion protein, which disrupts the normal PML nuclear bodies (PML-NBs) to micro-speckled pattern, leading to loss of their original functions. Moreover, reformation of PML-NBs in APL by arsenic is considered as one of the important step for APL treatment. Leptomycin B (LMB), a nuclear export inhibitor, is commonly used to inhibit the proteins exporting from the nucleus to the cytoplasm. In the present study, we found that LMB could induce the reformation of PML-NBs in leukemia NB4 cells as well as in APL blast cells from the patients, implying that nuclear shuttle proteins might be involved in the reformation of PML-NBs. Herein, we further found that LMB totally lost the ability to induce PML-NBs reformation when the endogenous PML gene was knocked out, indicating that endogenous PML protein is probably involved in the reformation of PML-NBs. More interestingly, among all PML isoforms (i.e., seven isoforms), reformation of PML-NBs was only observed when co-transfection of PML-RARα with PML-I after LMB treatment. Similarly, deletion of nuclear export signal (NES) of PML-I could also reform PML-NBs, suggesting that the protein level of endogenous PML-I in nucleus is important for the reformation of PML-NBs that interfered by PML-RARα fusion protein. Additionally, LMB has synergistic effect with iAsIII on enhancing PML-RARα fusion protein degradation, and it might provide new insight into APL treatment at clinical level in the near future.

Irreversibility of arsenic trioxide induced PML/RARα fusion protein solubility changes.

Arsenic trioxide (As2O3) is one of the most effective drugs for the treatment of acute promyelocytic leukemia (APL), and induces the degradation of chimeric oncoprotein PML/RARα (P/R) and APL cell differentiation. Recent evidence has suggested that P/R fusion protein degradation by arsenic occurs through two steps, namely, rapid solubility change/shift of the P/R fusion protein following arsenic treatment (i.e., transfer of P/R protein from the soluble fraction to the insoluble pellet fraction), and subsequent degradation of these insoluble proteins. However, there is little information regarding the reversibility of arsenic induced P/R fusion protein solubility change as well as protein degradation in the insoluble fraction after removing arsenic. In this study, we used APL cell line NB4 or P/R and PML over-expressed 293T cells as well as HeLa cells to reveal the solubility change of P/R and PML by arsenic exposure, and further determined the fate of these insoluble proteins after the removal of arsenic. Here, for the first time, we found that arsenic induced P/R or PML protein solubility change is an irreversible process. Once arsenic induces a P/R or PML protein solubility change, these insoluble proteins could be degraded by the proteasomal pathway even without continuous arsenic treatment. However, PML and P/R proteins can be newly synthesized after the removal of arsenic, suggesting that great caution should be taken in the clinical therapy of APL patients before ending arsenic treatment.

Integrity of zinc finger motifs in PML protein is necessary for inducing its degradation by antimony.

Antimony (Sb) belongs to the same group as arsenic (As) in the periodic table, and both share similar characteristics. However, Sb2O3 (SbIII) has no methylation capacity, unlike arsenic trioxide (As2O3). In the present study, we determined the effect of SbIII on NB4 cells and found that antimony could induce PML-RARα fusion protein degradation, reorganization of PML-NBs, and NB4 cell differentiation with low cytotoxicity. On the other hand, zinc finger motifs in PML protein are considered to be a key target binding site for arsenic-induced PML-RARα protein degradation. Interestingly, antimony and arsenic lost their ability to degrade PML-RARα fusion protein in NB4 cells following pretreatment with phenanthroline (i.e., chelator of zinc ions), indicating that the integrity of zinc finger motifs in PML-RARα fusion protein is a fundamental condition for inducing the protein's degradation by antimony and arsenic. Moreover, we found that SbIII could not induce mutant PML (e.g., A126V and L218P) solubility change and degradation, similar to As2O3. In contrast, we found that the organic antimony compound phenylstibine oxide (PSO) could induce mutant PML protein degradation. In conclusion, our results indicate that SbIII might also be a promising agent to treat acute promyelocytic leukemia, in the same manner as As2O3.

[Involvement of PML proteins in treatment of acute promyelocytic leukemia with arsenic trioxide].

Promyelocytic leukemia (PML) protein, a tumor suppressor, plays an important role in patients with acute promyelocytic leukemia (APL) receiving arsenic trioxide (As2O3) therapy. APL is a M3 subtype of acute myeloid leukemia (AML), which is characterized by expression of PML-RARα (P/R) fusion protein, leading to the oncogenesis. As2O3 is currently used as the first-line drug for patients with APL, and the mechanism may be:As2O3 directly binds to PML part of P/R protein and induces multimerization of related proteins, which further recruits different functional proteins to reform PML nuclear bodies (PML-NBs), and finally it degraded by SUMOylation and ubiquitination proteasomal pathway. Gene mutations may lead to relapse and drug resistance after As2O3 treatment. In this review, we discuss the structure and function of PML proteins; the pathogenesis of APL induced by P/R fusion protein; the involvement of PML protein in treatment of APL patient with As2O3; and explain how PML protein mutations could cause resistance to As2O3 therapy.

[Meta-analysis of Yinzhihuang oral liquid in treatment of intrahepatic cholestasis of pregnancy].

To systematically review the clinical efficacy and safety of Yinzhihuang oral liquid in the treatment of intrahepatic cholestasis of pregnancy(ICP). Literatures published by June 2016 were searched in databases, such as Medline, Pubmed, Cochrane Library, China National Knowledge Infrastructure(CNKI), Chinese Scientific Journals Full-text Database(VIP), Chinese biomedical literature database(CBM), and Wanfang Database. Randomized controlled trials(RCT) of Yinzhihuang oral liquid were collected according to the inclusion criteria, and the methodological quality of selected literatures was evaluated. The Meta-analysis was conducted by using RevMan 5.3 software. A total of 7 RCTs involving 711 patients were included. The results of Meta-analysis showed that, compared with control group, Yinzhihuang oral liquid significantly alleviated pruritus symptoms[MD=－0.68, 95%CI(－0.95,－041), P<0.000 01], reduced blood biochemical indexes including TBA[MD=－7.23, 95%CI (－10.88,－3.58), P=0.000 1], TB[MD=－1.90, 95%CI(－3.09,－0.70), P=0.002], ALT[MD=－39.08, 95%CI (－56.46,－21.70), P<0.000 1], and CG [MD=－0.71, 95%CI(－0.89,－0.52), P<0.000 01]. In the respect of pregnancy outcome, Yinzhihuang oral liquid can distinctly improve birth weight [MD=430.03, 95%CI (219.28, 640.78), P<0.000 1]. However, there was no significant difference in cesarean section rate [OR=0.93, 95%CI (0.36, 2.36), P=0.87], preterm birth rates [OR=0.63, 95%CI (0.28, 1.42), P=0.26], and neonatal asphyxia rate [OR=0.50, 95%CI (0.18, 1.43), P=0.20]. Yinzhihuang oral liquid showed better efficiency and slighter adverse reaction. However, more rigorously designed, double-blind, randomized controlled trials with large sample size and high quality are required to provide further evidences.

Methylated arsenic metabolites bind to PML protein but do not induce cellular differentiation and PML-RARα protein degradation.

Arsenic trioxide (As2O3) is one of the most effective therapeutic agents used for patients with acute promyelocytic leukemia (APL). The probable explanation for As2O3-induced cell differentiation is the direct targeting of PML-RARα oncoprotein by As2O3, which results in initiation of PML-RARα degradation. However, after injection, As2O3 is rapidly methylated in body to different intermediate metabolites such as trivalent monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)), therefore, it remains unknown that which arsenic specie is actually responsible for the therapeutic effects against APL. Here we have shown the role of As2O3 (as iAs(III)) and its intermediate metabolites (i.e., MMA(III)/DMA(III)) in NB4 cells. Inorganic iAs(III) predominantly showed induction of cell differentiation, while MMA(III) and DMA(III) specifically showed to induce mitochondria and endoplasmic reticulum-mediated apoptosis, respectively. On the other hand, in contrast to iAs(III), MMA(III) showed stronger binding affinity for ring domain of PML recombinant protein, however, could not induce PML protein SUMOylation and ubiquitin/proteasome degradation. In summary, our results suggest that the binding of arsenicals to the ring domain of PML proteins is not associated with the degradation of PML-RARα fusion protein. Moreover, methylated arsenicals can efficiently lead to cellular apoptosis, however, they are incapable of inducing NB4 cell differentiation.

Generation of thioarsenicals is dependent on the enterohepatic circulation in rats.

Three minor sulfur-containing arsenic metabolites: monomethylmonothioarsonic acid (MMMTA(V)), dimethylmonothioarsinic acid (DMMTA(V)), and dimethyldithioarsinic acid (DMDTA(V)) were recently found in human and animal urine after exposure to inorganic arsenic. However, it remains unclear how the thioarsenicals are formed in the body and then excreted into the urine. It is hypothesized that the generation of thioarsenicals occurs during enterohepatic circulation. To address this hypothesis, male Sprague Dawley (SD) rats and Eisai hyperbilirubinuric (EHB) rats (with deficiency of multidrug resistance-associated protein 2) were orally administered a single dose of inorganic arsenite (iAs(III)) at 3.0 mg kg(-1) of body weight. Five hours after dosing, less than 1.0% of the dose was recovered in the bile of EHB rats, while more than 27% of the dose was recovered in the bile of SD rats, with the majority being monomethylarsinodiglutathione [MMA(SG)(2)] with a small amount of arsenic triglutathione [iAs(SG)(3)]. During the early time periods (3 h and 6 h) the arsenic levels in the liver, red blood cells (RBCs) and plasma of EHB rats were higher than those of SD rats, and approximately 76% and 87% of the dose was recovered in the RBCs of SD and EHB rats, respectively, at day 5 after dosing. However, there were no significant differences in arsenic concentration in urine between the two types of animal. Regarding the arsenic species in the urine of both types of rat, significant levels of thiolated arsenicals MMMTA(V) and DMMTA(V) were detected in SD rat urine, however in EHB rat urine only low levels of DMMTA(V) were detected. The present result of the metabolic balance and speciation study suggests that the formation of MMMTA(V) and DMMTA(V) in rats is dependent on enterohepatic circulation. In addition, in vitro experiments indicated that arsenicals excreted from bile may be transformed by gastrointestinal microbiota into MMMTA(V) and DMMTA(V), which are then absorbed into the bloodstream and finally excreted into the urine.

Mitochondria are the main target organelle for trivalent monomethylarsonous acid (MMA(III))-induced cytotoxicity.

Excessive generation of reactive oxygen species (ROS) is considered to play an important role in arsenic-induced carcinogenicity in the liver, lungs, and urinary bladder. However, little is known about the mechanism of ROS-based carcinogenicity, including where the ROS are generated, and which arsenic species are the most effective ROS inducers. In order to better understand the mechanism of arsenic toxicity, rat liver RLC-16 cells were exposed to arsenite (iAs(III)) and its intermediate metabolites [i.e., monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III))]. MMA(III) (IC(50) = 1 µM) was found to be the most toxic form, followed by DMA(III) (IC(50) = 2 µM) and iAs(III) (IC(50) = 18 µM). Following exposure to MMA(III), ROS were found to be generated primarily in the mitochondria. DMA(III) exposure resulted in ROS generation in other organelles, while no ROS generation was seen following exposures to low levels of iAs(III). This suggests the mechanisms of induction of ROS are different among the three arsenicals. The effects of iAs(III), MMA(III), and DMA(III) on activities of complexes I-IV in the electron transport chain (ETC) of rat liver submitochondrial particles and on the stimulation of ROS production in intact mitochondria were also studied. Activities of complexes II and IV were significantly inhibited by MMA(III), but only the activity of complexes II was inhibited by DMA(III). Incubation with iAs(III) had no inhibitory effects on any of the four complexes. Generation of ROS in intact mitochondria was significantly increased following incubation with MMA(III), while low levels of ROS generation were observed following incubation with DMA(III). ROS was not produced in mitochondria following exposure to iAs(III). The mechanism underlying cell death is different among As(III), MMA(III), and DMA(III), with mitochondria being one of the primary target organelles for MMA(III)-induced cytotoxicity.

Distribution and speciation of arsenic after intravenous administration of monomethylmonothioarsonic acid in rats.

Quite a few new thioarsenicals have recently been found in urine of arsenic-exposed humans and animals, and some of them have been shown to be highly toxic to cells. However, little is known about their toxic effects and metabolism in the body. In order to elucidate the toxic mechanism of thioarsenicals, we further focused on the distribution and metabolism of monomethylmonothioarsonic acid (MMMTA(V)) in rats. MMMTA(V) was synthesized chemically and injected intravenously into rats at the dose of 0.5mg As/kg, followed by speciation analysis of selected organs and body fluids at 10 min and 12h after the injection. MMMTA(V) was excreted into urine in its intact form, and approximately 35% of the dose was recovered in urine at 12h after the injection, suggesting that MMMTA(V) was taken up more effectively by organs/tissues than non-thiolated, monomethylarsonous acid (MMA(V)) previously studied. On the other hand, the liver and kidneys contained arsenic that was in a protein-binding form with free forms of DMA(V) or DMDTA(V) at 10 min, and disappeared at 12h after the injection. Moreover, these bound arsenic species in kidneys were converted back to MMA(V) after oxidation with H(2)O(2), suggesting that the arsenic bound to proteins had been reduced within the body and was in a trivalent oxidation state. In red blood cells (RBCs), most of the arsenic was in the form of DMA(III) bound to hemoglobin (Hb), and approximately 40% of the dose was recovered in RBCs at 12h after injection. These results indicate that arsenic accumulated preferentially in RBCs after being transformed to DMA(III). In addition, we have also discussed the effect of MMMTA(V) on viability of human bladder cancer T24 cells in comparison with MMA(V). Consequently, MMMTA(V) was assumed to be a more toxic arsenic metabolite than non-thiolated MMA(V).