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Despite significant advancements in the field of oncology, cancers still pose one of the greatest challenges of modern healthcare. Given the cytoskeleton's pivotal role in regulating mechanisms critical to cancer development, further studies of the cytoskeletal elements could yield new practical applications. Septins represent a group of relatively well-conserved GTP-binding proteins that constitute the fourth component of the cytoskeleton. Septin 9 (SEPT9) has been linked to a diverse spectrum of malignancies and appears to be the most notable septin member in that category. SEPT9 constitutes a biomarker of colorectal cancer (CRC) and has been positively correlated with a high clinical stage in breast cancer, cervical cancer, and head and neck squamous cell carcinoma. SEPT9_i1 represents the most extensively studied isoform of SEPT9, which substantially contributes to carcinogenesis, metastasis, and treatment resistance. Nevertheless, the mechanistic basis of SEPT9_i1 oncogenicity remains to be fully elucidated. In this review, we highlight SEPT9's and SEPT9_i1's structures and interactions with Hypoxia Inducible Factor α (HIF-1 α) and C-Jun N-Terminal Kinase (JNK), as well as discuss SEPT9_i1's contribution to aneuploidy, cell invasiveness, and taxane resistance—key phenomena in the progression of malignancies. Finally, we emphasize forchlorfenuron and other septin inhibitors as potential chemotherapeutics and migrastatics. [ABSTRACT FROM AUTHOR]

Simple Summary: Our research focuses on the molecular mechanism of forchlorfenuron (FCF), a plant growth regulator widely used in agriculture to enhance fruit size and quality, and explored its potential in cancer treatment. Despite its known effects, the specific cellular and molecular mechanisms behind FCF's actions have been unclear. Our study reveals a new mechanism: FCF inhibits mitochondrial respiration, affecting crucial cellular energy processes. This discovery sheds light on how FCF connects to the regulation of HIF-1α and glucose uptake observed in previous studies. Our findings not only deepen our understanding of FCF but also hint at the possibility of novel cancer therapies when combined with existing glycolytic inhibitors. Forchlorfenuron (FCF) is a widely used plant cytokinin that enhances fruit quality and size in agriculture. It also serves as a crucial pharmacological tool for the inhibition of septins. However, the precise target of FCF has not yet been fully determined. This study reveals a novel target of FCF and elucidates its downstream signaling events. FCF significantly impairs mitochondrial respiration and mediates metabolic shift toward glycolysis, thus making cells more vulnerable to glycolysis inhibition. Interestingly, FCF's impact on mitochondrial function persists, even in cells lacking septins. Furthermore, the impaired mitochondrial function leads to the degradation of HIF-1α, facilitated by increased cellular oxygen. FCF also induces AMPK activation, suppresses Erk1/2 phosphorylation, and reduces the expression of HER2, β-catenin, and PD-L1. Endometrial cancer is characterized by metabolic disorders such as diabetes and aberrant HER2/Ras-Erk1/2/β-catenin signaling. Thus, FCF may hold promise as a potential therapeutic in endometrial cancer. [ABSTRACT FROM AUTHOR]

The synthetic cytokinin forchlorfenuron (FCF), while seemingly presenting relatively low toxicity for mammalian organisms, has been the subject of renewed scrutiny in the past few years due to its increasing use in fruit crops and potential for bioaccumulation. Despite many toxicological properties of FCF being known, little research has been conducted on the toxicological effects of its secondary metabolites. Given this critical gap in the existing literature, understanding the formation of relevant FCF secondary metabolites and their association with mammalian metabolism is essential. To investigate the formation of FCF metabolites in sufficient quantities for toxicological studies, a panel of four fungi were screened for their ability to catalyze the biotransformation of FCF. Of the organisms screened, Cunninghamella elegans (ATCC 9245), a filamentous fungus, was found to convert FCF to 4-hydroxyphenyl-forchlorfenuron, the major FCF secondary metabolite identified in mammals, after 26 days. Following the optimization of biotransformation conditions using a solid support system, media screening, and inoculation with a solid pre-formed fungal mass of C. elegans, this conversion time was significantly reduced to 7 days—representing a 73% reduction in total reaction time as deduced from the biotransformation products and confirmed by LC-MS, NMR spectroscopic data, as well as a comparison with synthetically prepared metabolites. Our study provides the first report of the metabolism of FCF by C. elegans. These findings suggest that C. elegans can produce FCF secondary metabolites consistent with those produced via mammalian metabolism and could be used as a more efficient, cost-effective, and ethical alternative for producing those metabolites in useful quantities for toxicological studies. [ABSTRACT FROM AUTHOR]

In this study, Ag-CaCO3 nanocomposites were synthesized using silver nitrate as the precursor solution based on calcium carbonate nanoparticles (CaCO3 NPs). The synthesis involved the reaction of calcium lignosulphonate and sodium bicarbonate. The properties of Ag-CaCO3 nanocomposites were studied by various technologies, including an ultraviolet–visible spectrophotometer, a transmission electron microscope, and a Raman spectrometer. The results showed that Ag-CaCO3 nanocomposites exhibited a maximum UV absorption peak at 430 nm, the surface-enhanced Raman spectroscopy (SERS) activity of Ag-CaCO3 nanocomposites was evaluated using mercaptobenzoic acid (MBA) as the marker molecule, resulting in an enhancement factor of 6.5 × 104. Additionally, Ag-CaCO3 nanocomposites were utilized for the detection of forchlorfenuron. The results demonstrated a linear relationship in the concentration range of 0.01 mg/mL to 2 mg/mL, described by the equation y = 290.02x + 1598.8. The correlation coefficient was calculated to be 0.9772, and the limit of detection (LOD) was determined to be 0.001 mg/mL. These findings highlight the relatively high SERS activity of Ag-CaCO3 nanocomposites, making them suitable for analyzing pesticide residues and detecting toxic and harmful molecules, thereby contributing to environmental protection. [ABSTRACT FROM AUTHOR]

Forchlorfenuron is a widely used plant growth regulator to support the pollination and fruit set of oriental melons. It is critical to investigate the spatial distribution and migration characteristics of forchlorfenuron among fruit tissues to understand its metabolism and toxic effects on plants. However, the application of imaging mass spectrometry in pesticides remains challenging due to the usually extremely low residual concentration and the strong interference from plant tissues. In this study, a matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) method was developed for the first time to obtain the dynamic images of forchlorfenuron in oriental melon. A quantitative assessment has also been performed for MALDI-MSI to characterize the time-dependent permeation and degradation sites of forchlorfenuron in oriental melon. The majority of forchlorfenuron was detected in the exocarp and mesocarp regions of oriental melon and decreased within two days after application. The degradation rate obtained by MALDI-MSI in this study was comparable to that obtained by HPLC-MS/MS, indicating that the methodology and quantification approach based on the MALDI-MSI was reliable and practicable for pesticide degradation study. These results provide an important scientific basis for the assessment of the potential risks and effects of forchlorfenuron on oriental melons. [ABSTRACT FROM AUTHOR]

Septin7 as a unique member of the GTP binding protein family, is widely expressed in the eukaryotic cells and considered to be essential in the formation of hetero-oligomeric septin complexes. As a cytoskeletal component, Septin7 is involved in many important cellular processes. However, its contribution in striated muscle physiology is poorly described. In skeletal muscle, a highly orchestrated process of migration is crucial in the development of functional fibers and in regeneration. Here, we describe the pronounced appearance of Septin7 filaments and a continuous change of Septin7 protein architecture during the migration of myogenic cells. In Septin7 knockdown C2C12 cultures, the basic parameters of migration are significantly different, and the intracellular calcium concentration change in migrating cells are lower compared to that of scrambled cultures. Using a plant cytokinin, forchlorfenuron, to dampen septin dynamics, the altered behavior of the migrating cells is described, where Septin7-depleted cells are more resistant to the treatment. These results indicate the functional relevance of Septin7 in the migration of myoblasts, implying its contribution to muscle myogenesis and regeneration. [ABSTRACT FROM AUTHOR]

Forchlorfenuron (CPPU) is a widely used plant growth regulator in agriculture, and CPPU residue in food can cause harm to human health. Thus, it is necessary to develop a rapid and sensitive detection method for CPPU monitoring. In this study, a new monoclonal antibody (mAb) against CPPU with high affinity was prepared by a hybridoma technique, and a magnetic bead (MB)-based analytical method was established for the determination of CPPU by a one-step procedure. Under optimized conditions, the detection limit of the MB-based immunoassay was as low as 0.0004 ng/mL, which was five times more sensitive than the traditional indirect competitive ELISA (icELISA). In addition, the detection procedure took less than 35 min, a significant improvement over the 135 min required for icELISA. The selectivity test of the MB-based assay also showed negligible cross-reactivity with five analogues. Furthermore, the accuracy of the developed assay was assessed by the analysis of spiked samples, and the results agreed well with those obtained by HPLC. The excellent analytical performance of the proposed assay suggests its great potential for routine screening of CPPU, and it provides a basis for promoting the application of more immunosensors in the quantitative detection of low concentrations of small organic molecules in food. [ABSTRACT FROM AUTHOR]

Aroma is a crucial factor determining the market value and consumer satisfaction of fresh oriental melon. However, few studies focus on the volatile flavor of fresh oriental melon, and the effect of forchlorfenuron application on the aroma profile is unclear. This study characterized the volatile profile of fresh oriental melon fruit after forchlorfenuron application by E-nose and HS-GC-IMS. The holistic variation of volatile compounds exhibited evident distinction based on linear discriminant analysis (LDA) with E-nose. Forty-eight volatile compounds were identified from fresh oriental melon via GC-IMS, mainly esters, alcohols, aldehydes, and ketones, along with smaller quantities of sulfides and terpenes. Compared to pollination melon fruits, 13 critical different volatile flavor compounds were screened out in forchlorfenuron application groups by the PLS-DA model, imparting sweet fruity flavor. The results of the current study provide a valuable basis for evaluating the flavor quality of oriental melon after forchlorfenuron treatment. [ABSTRACT FROM AUTHOR]

In this study, a monoclonal antibody (mAb) specific to forchlorfenuron (CPPU) with high sensitivity and specificity was produced and designated (9G9). To detect CPPU in cucumber samples, an indirect enzyme-linked immunosorbent assay (ic-ELISA) and a colloidal gold nanobead immunochromatographic test strip (CGN-ICTS) were established using 9G9. The half-maximal inhibitory concentration (IC50) and the LOD for the developed ic-ELISA were determined to be 0.19 ng/mL and 0.04 ng/mL in the sample dilution buffer, respectively. The results indicate that the sensitivity of the antibodies prepared in this study (9G9 mAb) was higher than those reported in the previous literature. On the other hand, in order to achieve rapid and accurate detection of CPPU, CGN-ICTS is indispensable. The IC50 and the LOD for the CGN-ICTS were determined to be 27 ng/mL and 6.1 ng/mL. The average recoveries of the CGN-ICTS ranged from 68 to 82%. The CGN-ICTS and ic-ELISA quantitative results were all confirmed by liquid chromatography—tandem mass spectrometry (LC-MS/MS) with 84–92% recoveries, which indicated the methods developed herein are appropriate for detecting CPPU in cucumber. The CGN-ICTS method is capable of both qualitative and semiquantitative analysis of CPPU, which makes it a suitable alternative complex instrument method for on-site detection of CPPU in cucumber samples since it does not require specialized equipment. [ABSTRACT FROM AUTHOR]

Malignant mesothelioma (MM) is a currently incurable, aggressive cancer derived from mesothelial cells, most often resulting from asbestos exposure. The current first-line treatment in unresectable MM is cisplatin/pemetrexed, which shows very little long-term effectiveness, necessitating research for novel therapeutic interventions. The existing chemotherapies often act on the cytoskeleton, including actin filaments and microtubules, but recent advances indicate the 'fourth' form consisting of the family of septins, representing a novel target. The septin inhibitor forchlorfenuron (FCF) and FCF analogs inhibit MM cell growth in vitro, but at concentrations which are too high for clinical applications. Based on the reported requirement of the chloride group in the 2-position of the pyridine ring of FCF for MM cell growth inhibition and cytotoxicity, we systematically investigated the importance (cell growth-inhibiting capacity) of the halogen atoms fluorine, chlorine, bromine and iodine in the 2- or 3-position of the pyridine ring. The MM cell lines ZL55, MSTO-211H, and SPC212, and—as a control—immortalized Met-5A mesothelial cells were used. The potency of the various halogen substitutions in FCF was mostly correlated with the atom size (covalent radius); the small fluoride analogs showed the least effect, while the largest one (iodide) most strongly decreased the MTT signals, in particular in MM cells derived from epithelioid MM. In the latter, the strongest effects in vitro were exerted by the 2-iodo and, unexpectedly, the 2-trifluoromethyl (2-CF3) FCF analogs, which were further tested in vivo in mice. However, FCF-2-I and, more strongly, FCF-2-CF3 caused rapidly occurring strong symptoms of systemic toxicity at doses lower than those previously obtained with FCF. Thus, we investigated the effectiveness of FCF (and selected analogs) in vitro in MM cells which were first exposed to cisplatin. The slowly appearing population of cisplatin-resistant cells was still susceptible to the growth-inhibiting/cytotoxic effect of FCF and its analogs, indicating that cisplatin and FCF target non-converging pathways in MM cells. Thus, a combination therapy of cisplatin and FCF (analogs) might represent a new avenue for the treatment of repopulating chemo-resistant MM cells in this currently untreatable cancer. [ABSTRACT FROM AUTHOR]

The plant growth regulator forchlorfenuron is often applied to promote fruit setting and development in cucumber production. However, the effect of forchlorfenuron on the appearance and nutritional quality of cucumber is unknown. In the present study, forchlorfenuron was applied to female flowers 1 day before anthesis and at the day of anthesis. The application of forchlorfenuron successfully induced parthenocarpic fruit formation in cucumber. In addition, cytokinin-responsive genes were upregulated under forchlorfenuron treatment. Fruit treated with forchlorfenuron did not differ from pollinated fruit in shape, texture and major nutrients, such as protein, total flavonoids and vitamin C, with the exception of the lower phenolic acid content. Overall, our finding suggests that forchlorfenuron could be vital in promoting the parthenocarpic fruit set without altering the quality of cucumber. [ABSTRACT FROM AUTHOR]

In this study, forchlorfenuron (CPPU) was coupled with succinic anhydride to yield a CPPU hapten (CPPU-COOH), and a high-affinity monoclonal antibody (mAb) that can specifically recognize CPPU was produced. Using this mAb as a recognition reagent, a sensitive indirect competitive enzyme-linked immunosorbent assay (icELISA) for CPPU was optimized, which exhibits an IC50 of 1.04 ng/mL, a limit of detection of 0.16 ng/mL, and a linear range of 0.31–3.43 ng/mL for CPPU. Cross-reactivity percentages with six analogues were all below 6%. The average recovery rates for cucumber and orange samples were from 85.23% to 119.14%. The analysis results of this icELISA showed good consistency with those from liquid chromatography mass spectrometry. These results suggest that the proposed icELISA provides a sensitive, specific, and reliable strategy for CPPU detection in food samples. [ABSTRACT FROM AUTHOR]

Forchlorfenuron (CPPU) is a plant growth regulator extensively used in agriculture. However, studies on CPPU pharmacokinetics are lacking. We established and validated a rapid, sensitive, and accurate liquid chromatography–mass spectrometry method for CPPU detection in rat plasma. CPPU pharmacokinetics was evaluated in adult and juvenile rats orally treated with 10, 30, and 90 mg/kg of the compound. The area under the plasma drug concentration–time curve from 0 to 24 h (AUC), at the final time point sampled (AUC0–t), and the maximum drug concentration of CPPU increased in a dose-dependent manner. The pharmacokinetic parameters AUC0–t and absolute bioavailability were higher in the juvenile rats than in adult rats. The mean residence time and AUC0–t of juvenile rats in the gavage groups, except for the 10 mg/kg dose, were significantly higher in comparison to those observed for adult rats (p < 0.001). The plasma clearance of CPPU in juvenile rats was slightly lower than that in the adult rats. Taken together, juvenile rats were more sensitive to CPPU than adult rats, which indicates potential safety risks of CPPU in minors. [ABSTRACT FROM AUTHOR]