Molecular mechanisms of platinum‑based chemotherapy resistance in ovarian cancer (Review)

Targeting ovarian cancer: The promise of liposome-based therapies

A major cause of mortality among gynecological cancers, ovarian cancer is frequently unresponsive to standard therapies because to systemic toxicity and medication resistance. The contribution of liposomal drug delivery systems, specifically pegylated liposomal doxorubicin (PLD), to the advancement of ovarian cancer treatment is examined in this review. Liposomes, spherical lipid vesicles consisting of bilayer phospholipids, enable better drug delivery by preserving encapsulated pharmaceuticals and enabling tailored administration to tumor areas. In comparison to traditional doxorubicin, PLD has a better pharmacokinetic profile and less cardiotoxicity, according to the analysis, which examines several trials showing its effectiveness in treating both platinum-sensitive and platinum-resistant ovarian cancer. Furthermore, studies on liposomal versions of other medications, such as paclitaxel and cisplatin, demonstrate encouraging effects in terms of overcoming drug resistance and enhancing therapeutic outcomes. Recent advancements in tailored liposomal delivery systems that include components such tumor-specific peptides and folate receptors show improved tumor selectivity and fewer adverse effects. The study also looks at new combination treatments that use liposomal formulations with immunotherapeutic and new targeted medicines. Although liposomal drug delivery methods have great potential for treating ovarian cancer, further study is required to maximize their effectiveness, reduce side effects, and get beyond resistance mechanisms. These developments in liposomal technology are a major step toward turning ovarian cancer from a deadly illness into a chronic condition that can be managed, possibly increasing patient survival and quality of life.

Cinobufagin regulates the microRNA-149-3p/AFF4 axis to affect the proliferation and apoptosis of cisplatin-resistant ovarian cancer cells

Although cinobufagin has been demonstrated to inhibit the growth of various malignant tumors, its functional role in ovarian cancer remains unclear. In light of this, the present study aims to thoroughly investigate the effects of cinobufagin on ovarian cancer progression and elucidate its underlying molecular mechanisms, thereby providing novel insights into future therapeutic strategies. A2780/DDP, a cisplatin-resistant cell line for ovarian cancer, was treated with gradient doses of cinobufagin. The microRNA-149-3p and AFF4 binding sites were predicted by bioinformatics. In cisplatin-resistant ovarian cancer cells, microRNA-149-3p and AFF4 expression were detected using qRT-PCR, and the binding association between microRNA-149-3p and AFF4 was confirmed by dual-luciferase and RIP assays. Cell viability was assessed using the CCK-8 test, cell proliferation was identified using the EdU assay and colony formation, and cell apoptosis was identified using flow cytometry. The results showed that cinobufagin inhibited the proliferation and promoted apoptosis of cisplatin-resistant ovarian cancer cells. microRNA-149-3p was highly expressed in cisplatin-resistant ovarian cancer cells, while AFF4 was lowly expressed in these cells. Overexpression of microRNA-149-3p promoted the proliferation and inhibited the apoptosis of cisplatin-resistant ovarian cancer cells, which was reversed by the addition of cinobufagin. Overexpression of AFF4 suppressed proliferation and promoted apoptosis of cisplatin-resistant ovarian cancer cells. MicroRNA-149-3p repressed AFF4 expression, and partial attenuation of the effects of AFF4 overexpression on cell phenotype was observed when microRNA-149-3p was overexpressed. In conclusion,cinobufagin regulated microRNA-149-3p/AFF4 axis to inhibit proliferation of ovarian cancer cells and promote cell apoptosis. Targeting the microRNA-149-3p/AFF4 axis with cinobufagin could represent a novel therapeutic strategy for ovarian cancer.

Stable isotope tracing reveals glucose metabolism characteristics of drug-resistant B-cell acute lymphoblastic leukemia

BACKGROUND

Adult B-cell acute lymphocytic leukemia (B-ALL) is a malignant hematologic tumor characterized by the uncontrolled proliferation of B-cell lymphoblasts in the bone marrow. Despite advances in treatment, including chemotherapy and consolidation therapy, many B-ALL patients experience unfavorable prognoses due to the development of drug resistance. The precise mechanisms governing chemotherapy resistance, particularly those related to metabolic reprogramming within tumors, remain inadequately elucidated.

RESULTS

Nalm6/DOX cells exhibited significantly elevated levels of glucose, pyruvate, alanine, glutamine, and glycine compared to Nalm6 cells. Conversely, reduced levels of citrate, acetate, and leucine were observed in Nalm6/DOX cells. Upon exposure to the culture medium supplemented with tracer 13C6-glucose, the Nalm6/DOX cells showed an increase in the abundance of 13C-alanine and a decrease in the levels of 13C-lactate, indicating impaired utilization of 13C-pyruvate. Combining β-chloro-alanine (ALTi) with DOX could decrease the drug resistance phenotype of Nalm6/DOX cells. The results demonstrated that glycolysis and tricarboxylic acid cycle were suppressed in Nalm6/DOX cells, while metabolic flux through the alanine and glutamine pathways was increased. Therefore, inhibition of alanine biosynthesis in Nalm6/DOX exhibits the potential to reverse drug resistance.

SIGNIFICANCE

A new insight into the impact of metabolism on chemotherapy resistance in B-ALL has been gained through the use of stable isotope resolved metabolomics based on nuclear magnetic resonance and ultra-performance liquid chromatography/tandem mass spectrometry. This provides promising ways for the development of innovative therapeutic strategies to alleviate drug resistance and relapse in affected patients.

Loss of primary cilia promotes EphA2-mediated endothelial-to-mesenchymal transition in the ovarian tumor microenvironment

Endothelial-to-mesenchymal transition (EndMT) is closely associated with tumor progression. Endothelial cells (ECs) in the tumor microenvironment (TME) use EndMT programs to facilitate tumor progression; however, the underlying mechanisms in ovarian cancer are poorly understood. Here, we describe the involvement of primary cilia in EndMT of the ovarian TME. We showed that ECs from human ovarian tumors displayed robust EndMT and impaired cilia formation, as was also observed in ECs in response to ovarian cancer cell culture-conditioned media (OV-CM). Notably, ECs lacking primary cilia exhibited increased OV-CM-induced EndMT. Vascular abnormalities, such as enhanced cell migration and vessel permeability, were observed in vitro. Furthermore, in vivo experiments using endothelial-specific kinesin family member 3A (Kif3a)-knockout mice showed enhanced EndMT in the ovarian TME. Mechanistically, we identified ephrin type-A receptor 2 (EphA2) as a key regulator of EndMT. Upon OV-CM treatment, EphA2 expression increased, and depletion of EphA2 in ECs decreased OV-CM-induced EndMT and vascular abnormalities. These results highlight that the loss of primary cilia and the consequent EphA2 activation are key mechanisms by which EndMT programs induce the acquisition of cancer-associated fibroblast-like cells in the ovarian TME, thereby promoting ovarian cancer progression.

Deep learning based on ultrasound images to predict platinum resistance in patients with epithelial ovarian cancer

BACKGROUND

The study aimed at developing and validating a deep learning (DL) model based on the ultrasound imaging for predicting the platinum resistance of patients with epithelial ovarian cancer (EOC).

METHODS

392 patients were enrolled in this retrospective study who had been diagnosed with EOC between 2014 and 2020 and underwent pelvic ultrasound before initial treatment. A DL model was developed to predict patients' platinum resistance, and the model underwent evaluation through receiver-operating characteristic (ROC) curves, decision curve analysis (DCA), and calibration curve.

RESULTS

The ROC curves showed that the area under the curve (AUC) of the DL model for predicting patients' platinum resistance in the internal and external test sets were 0.86 (95% CI 0.83-0.90) and 0.86 (95% CI 0.84-0.89), respectively. The model demonstrated high clinical value through clinical decision curve analysis and exhibited good calibration efficiency in the training cohort. Kaplan-Meier analyses showed that the model's optimal cutoff value successfully distinguished between patients at high and low risk of recurrence, with hazard ratios of 3.1 (95% CI 2.3-4.1, P < 0.0001) and 2.9 (95% CI 2.3-3.9; P < 0.0001) in the high-risk group of the internal and external test sets, serving as a prognostic indicator.

CONCLUSIONS

The DL model based on ultrasound imaging can predict platinum resistance in patients with EOC and may support clinicians in making the most appropriate treatment decisions.

A comprehensive overview of ovarian cancer stem cells: correlation with high recurrence rate, underlying mechanisms, and therapeutic opportunities

Ovarian cancer is one of the most lethal gynecological malignancies, with a recurrence rate of 70-80%, particularly in patients diagnosed at advanced stages (stage III or IV), where the five-year survival rate falls below 30%. A key driver of this recurrence is the presence of cancer stem cells (CSCs), which exhibit resistance to chemotherapy and possess the capacity for self-renewal, plasticity, and tumor regeneration. The tumor microenvironment (TME) plays a crucial role in maintaining ovarian cancer stem cells (OCSCs) by providing nutrient and oxygen gradients, extracellular matrix (ECM) interactions, immune cell modulation, and support from cancer-associated fibroblasts (CAFs). CAFs secrete growth factors, cytokines, and ECM components that create a pro-tumorigenic niche, promoting CSC maintenance, invasion, and chemoresistance. Additionally, dysregulation of critical signaling pathways, including WNT, NOTCH, PI3K/AKT/mTOR, TGF-β, JAK/STAT, Hedgehog, NF-κB, and Hippo, supports CSC stemness, plasticity, maintenance, and adaptability, thereby increasing their survival and progression. Numerous inhibitors targeting these pathways have shown promise in preclinical studies. This review discusses the molecular mechanisms underlying CSC-mediated recurrence in ovarian cancer and highlights emerging therapeutic strategies. Particular emphasis is placed on the potential of combination therapies involving routine platinum or taxane based regimens with OCSC inhibitors to overcome chemoresistance, reduce recurrence rates, and improve survival outcomes for patients with advanced-stage ovarian cancer.

Natural compounds targeting ferroptosis in ovarian cancer: Research progress and application potential

Ovarian cancer (OC) is among the most common malignancies in the female reproductive system, marked by high rates of recurrence and mortality. Conventional chemotherapy, however, faces limitations due to the development of drug resistance, which hinders its effectiveness. Ferroptosis, an atypical form of programmed cell death distinct from autophagy, apoptosis, and necrosis, the relationship with tumors has become a hot research area in cancer studies in recent years. Anticancer therapies that target ferroptosis show strong potential in improving prognosis and counteracting chemotherapy resistance. Natural compounds, as a valuable source of novel targeted anticancer agents, its significant role in inhibiting tumor cell proliferation and metastasis and improving therapeutic sensitivity has been demonstrated in numerous existing studies. This review summarizes a range of natural compounds that target ferroptosis in OC cells, discussing their active components, mechanisms of action, and therapeutic potential, thereby providing useful insights for future targeted therapy and research in OC.

Circulating extracellular vesicles protein expression for early prediction of platinum-resistance in high-grade serous ovarian cancer

Platinum resistance in high-grade serous ovarian carcinoma (HGSOC) portends a poor prognosis. Although initial platinum-based chemotherapy response rates are high, 15-20% of patients demonstrate primary resistance to platinum therapy and almost all patients will develop platinum resistance in the recurrent setting. No predictive or diagnostic biomarkers have been utilized specific to platinum resistance. This study aimed to identify candidate biomarkers for platinum resistance in HGSOC using an extracellular vesicle (EV) based approach. We found differentially expressed and distinct EV proteins, namely TMEM205 and CFH, in patients with platinum-resistant (PR) HGSOC compared to those of platinum-sensitive (PS) patients, utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS). Expression of these EV proteins were validated in patient-derived PR cell lines as well as in clinically relevant mouse models of HGSOC post-platinum therapy. We corroborated these findings using serum samples from patients with PS and PR-HGSOC. Both EV CFH and EV TMEM205 exhibited excellent diagnostic capability for PR as noted by receiver operating characteristic curves with area under the curve values of 0.95 and 0.84, respectively. The high diagnostic performance of TMEM205 and CFH within EVs compared to the relatively poor performance of conventional serum proteins such as Ca125 suggests their robust potential as non-invasive biomarkers for detecting platinum resistance in HGSOC. Furthermore, the ROC curve for the combined biomarker demonstrated excellent diagnostic performance, with an AUC of 0.973, a true positive rate (TPR) of 0.938, and a false positive rate (FPR) of 0.062. Incorporating this multi-protein biomarker panel alongside established biomarkers further enhances diagnostic accuracy. Serum EV CFH and TMEM205 are promising biomarkers for early detection of platinum resistance in HGSOC and may highlight underlying chemoresistance mechanisms, offering potential future therapeutic targets.

Ovarian cancer and the heart: pathophysiology, chemotherapy-induced cardiotoxicity, and new therapeutic strategies

Ovarian Cancer (OC) is recognized as the most lethal gynecologic malignancy, characterized by numerous genetic mutations that trigger uncontrolled cellular growth and replication. Emerging evidence suggests that non-coding RNAs including miRNAs and lncRNAs significantly influence OC through their multiple roles including tumor initiation, progression, metastasis, immune evasion, and chemoresistance, making them promising diagnostic markers and therapeutic targets. The primary approach to treating OC typically involves cytoreductive surgery followed by chemotherapy. However, the chemotherapeutic agents, particularly the anthracyclines such as doxorubicin (DOX), are known for their cardiotoxic effects, which can range from acute to chronic, potentially leading to heart failure and death. To enhance the overall treatment response and to minimize cardiotoxicity, alternative strategies have been explored. These include the use of liposomal doxorubicin (DOXIL) as a substitute for DOX, various radiotherapies, immunotherapies, and the co-administration of angiotensin-converting enzyme inhibitors and/or beta-blockers. Phosphodiesterase-5 inhibitors (PDE5i) have also demonstrated efficacy in reducing cardiotoxicity linked to cancer treatments and in promoting apoptosis in cancer cells across multiple cancer types. Although there is no current clinical trial directly examining the impact of PDE5i on reducing cardiotoxicity in OC, however emerging therapies such as Withaferin A, PARP inhibitors, and nanoparticle combination therapy show promise. Additional research is essential to develop treatments that are both effective against OC and less harmful to the heart.

The Persistent Power of the Taxane/Platin Chemotherapy

The cancer chemotherapy regimen of a taxane and platinum combination was developed more than forty years ago, yet remains the cornerstone of treatment for several major cancer types today. Although many new agents targeting cancer genes and pathways have been developed and evaluated, none have been sufficient to replace the long-established taxane/platinum combination. This leads us to ponder why, after four decades of colossal efforts, multiple discoveries, and tremendous advances in understanding gene mutations and biology, the development of conceptually superior targeted therapies has not yet achieved overwhelming success in replacing cytotoxic chemotherapy. The concept of targeted therapy is based on the idea that blocking the altered pathway(s) crucial for cancer development (and maintenance), the disturbance in cellular signaling, metabolism, and functions will make the targeted cancer cells unfit and trigger programmed cell death in cancer cells, but without the significant side effects that limit chemotherapy. We propose that the lack of anticipated triumphs of targeted therapy stems from the desensitization of programmed cell death pathways during neoplastic transformation and malignant progression of cancer cells. This renders the targeting drugs largely ineffective at killing cancer cells and mostly insufficient in clinical implements. Recent advances in understanding suggest that, in contrast to targeted therapies, taxanes and platinum agents kill cancer cells by physical rupturing nuclear membranes rather than triggering apoptosis, making their effect independent of the intrinsic cellular programmed cell death mechanism. This new recognition of the non-programmed cell death mechanism in the success of chemotherapeutic agents, such as taxanes and platinum, may inspire oncologists and cancer researchers to focus their efforts more productively on developing effective non-programmed cell death cancer therapies to replace or significantly improve the application of the current standard taxane/platinum regimens.

Emerging role of deubiquitinases in modulating cancer chemoresistance

Chemotherapy remains a gold standard in cancer treatment by targeting the rapidly dividing cancer cells. However, chemoresistance is a major obstacle to successful cancer treatment, often leading to recurrence, metastasis, and high mortality. Deubiquitinases (DUBs), enzymes that remove ubiquitin and stabilize proteins, have been implicated in chemoresistance and can either promote therapeutic resistance or enhance sensitivity depending on their targets. In this review, we highlight the chemoresistance mechanisms of DUBs in various cancers, including breast, lung, liver, gastrointestinal, colorectal, ovarian, prostate, and blood cancers. Given these mechanisms, the development of DUB inhibitors has gained considerable attention in cancer therapeutics and combination therapies involving these inhibitors show potential to overcome drug resistance and improving treatment outcomes.

Urinary concentrations of phthalate metabolites and the survival of high-grade serous ovarian cancer with advanced stage

Phthalates have been reported to increase the risk of various hormone-dependent cancers. However, there is still a lack of evidence regarding the association between phthalates and overall survival (OS) in advanced high-grade serous ovarian cancer (HGSOC). This study investigated the relationship between urinary phthalate metabolites and OS in patients with HGSOC using a nested case-control study within the Ovarian Cancer Follow-Up Study. We matched 159 deceased patients with HGSOC to 159 survivors by age at diagnosis, body mass index, and sampling date. Spot urine samples were analyzed for ten phthalate metabolites and five classes of phthalate molar sums via mass spectrometry. Conditional logistic regression models were employed to calculate odds ratios (ORs) and 95% confidence intervals (CIs), comparing the highest tertile with the lowest. We found that the highest tertiles of mono-2-ethyl-5-oxohexyl phthalates and monoethyl phthalates were associated with poorer OS, with ORs (95%CIs) being 4.24 (1.46, 12.32) and 3.28 (1.16, 9.22), respectively. Additionally, the highest tertiles of the sum of di(2-ethylhexyl) phthalate metabolites, the sum of high-molar-weight phthalate metabolites, and the sum of 10 phthalate metabolites, were associated with worse OS, with ORs (95%CIs) were 18.4 (4.14, 81.87), 9.28 (2.87, 30.08), and 5.94 (2.00, 17.64), respectively. Our study suggests that exposure to high levels of phthalates may be associated with poorer OS in patients with advanced HGSOC, particularly exposure to di(2-ethylhexyl) phthalates. Since it is widely used in personal care products, avoiding the use of these products may improve the OS of patients with HGSOC.

CRISPR/Cas9 system: a novel approach to overcome chemotherapy and radiotherapy resistance in cancer

Cancer presents a global health challenge with rising incidence and mortality. Despite treatment advances in cancer therapy, radiotherapy and chemotherapy remained the most common treatments for all types of cancers. However, resistance phenotype in cancer cells leads to unsatisfactory results in the efficiency of therapeutic strategies. Therefore, researchers strive to propose effective solutions to overcome treatment failure, which requires a deep knowledge of treatment-resistant mechanisms. The progression and occurrence of tumors can be attributed to gene mutation. Over the past decade, the emergence of clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR/Cas9) genome editing has revolutionized cancer research. This versatile technology enables cancer modeling, manipulation of specific DNA sequences, and genome-wide screening. CRISPR/Cas9 is an effective tool for identifying radio- and chemoresistance genes and offering potential adjunctive treatments to overcome tumor recurrence after chemo- and radiotherapy. This article aims to explain the potential of the CRISPR/Cas9 system in improving the effectiveness of chemo- and radiotherapy and ultimately overcoming treatment failure.

Mechanistic insights into SENP1 and OCT4 interaction in promoting drug resistance and stem cell features in colon cancer

This study explores the molecular mechanism by which sentrin/SUMO-specific protease 1 (SENP1) promotes cisplatin (Cis) resistance and tumor stem cell characteristics in colon adenocarcinoma (COAD) through deSUMOylation-mediated modification of octamer-binding transcription factor 4 (OCT4). By analyzing single-cell and transcriptome sequencing datasets, we identified key genes and regulatory pathways in both resistant and sensitive COAD cells. Malignant cells were isolated and evaluated for stemness using the infercnv package, and differential genes between Cis-resistant and -sensitive groups were identified. Machine learning algorithms highlighted essential genes, and databases predicted interaction sites between OCT4 and SENP1. In vitro experiments using enriched HCT116 stem cells revealed that SENP1 and OCT4 expression significantly elevated CD44 and CD133 levels, enhancing stemness. Functional assays showed that SENP1's deSUMOylation of OCT4 intensified Cis resistance, migration, and invasion in cisplatin-resistant cell line 116 (Cis-116) cells. In vivo, SENP1 knockdown reduced tumor growth and stem cell markers, whereas OCT4 overexpression escalated tumor metastasis and structural damage. These findings demonstrate that SENP1's modulation of OCT4 is central to COAD's resistance and stem cell properties, offering a novel target for COAD therapy.NEW & NOTEWORTHY This study uncovers the critical role of SENP1 in regulating OCT4 through deSUMOylation, driving Cis resistance and tumor stemness in COAD. Targeting this pathway may provide novel therapeutic strategies for COAD management.

Responsive boronate ester lipid nanoparticles for enhanced delivery of veliparib and platinum (IV) prodrug in chemotherapy

The chemotherapeutic effectiveness of breast cancer treatment is currently unsatisfactory due to inadequate drug delivery, suboptimal drug release, and drug inactivation. Herein, we present an innovative boronate ester lipid nanoformulation to improve the delivery of a platinum (IV) prodrug (Pt-C12) and veliparib (Veli), aiming to increase their therapeutic efficacy through a synergistic effect. We identify the optimal ratio of Pt-C12 to Veli for achieving synergy in vitro, followed by the encapsulation of Pt-C12 and Veli in lipid nanoparticles (NPs) incorporating responsive boronate ester lipids (LPC-PPE) to produce responsive lipid NPs (LPV NPs). These LPV NPs demonstrate high sensitivity to low levels of hydrogen peroxide (H2O2), enabling efficient drug release. In contrast, the nonresponsive lipid NP (DPV NP) control shows minimal responsiveness to H2O2. Furthermore, acidic tumor microenvironments trigger phenylboronic acid (PBA) generation from LPC-PPE in the LPV NPs. Compared with DPV NPs, the interaction between PBA on the LPV NPs and sugar components on tumor cells significantly improves LPV NP cellular uptake and lysosomal escape in vitro. Due to the enhanced cellular delivery and the synergistic drug combination, the LPV NPs induce an increase in apoptosis in 4 T1 cells compared with control groups. Moreover, the LPV NPs exhibit greater efficiency of drug delivery to tumors than the DPV NPs, and have a greater inhibitory effect on tumors than the controls. Overall, our findings highlight the potential of functional lipids and synergistic drug combinations in overcoming obstacles in breast cancer treatment and advancing the development of responsive delivery systems.

KRT14 knockdown reduces cisplatin resistance by lowering LRP11 expression levels in cisplatin-resistant ovarian cancer cell lines

Background

Platinum resistance is a major cause of mortality in patients with advanced ovarian cancer. Understanding the mechanisms underlying this resistance is essential for developing effective treatments to improve patient survival. Therefore, this study aimed to explore the role and mechanisms of keratin 14 (KRT14) in regulating cisplatin resistance in ovarian cancer.

Methods

We utilized quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting to measure messenger RNA (mRNA) and protein expression levels, respectively. Cisplatin-resistant cell lines (SK-OV-3/DDP and A2780/DDP) were transfected with small interfering RNA (siRNA) targeting KRT14 (si-KRT14) or a plasmid containing low-density lipoprotein receptor-related protein 11 (LRP11) to knock down KRT14 or overexpress LRP11, respectively. Differentially expressed mRNAs were identified using Illumina RNA sequencing. Cell viability and half-maximal inhibitory concentration (IC50) values were determined via cell counting kit-8 (CCK-8) assays, while apoptosis was assessed using flow cytometry and Hoechst 33258 staining.

Results

KRT14 mRNA and protein levels were significantly higher in SK-OV-3/DDP and A2780/DDP cells compared with their parental counterparts. KRT14 knockdown reduced the IC50 values, increased apoptosis, and decreased the levels of the multidrug resistance (MDR)-related proteins P-glycoprotein (P-gp) and MDR-associated protein 1 (MRP1). KRT14 knockdown in SK-OV-3/DDP and A2780/DDP cells revealed 24 differentially expressed mRNAs. Further analysis revealed that KRT14 knockdown notably reduced LRP11 expression. LRP11 overexpression increased IC50 values, suppressed apoptosis, and enhanced MDR-related protein expression, thus counteracting the effects of KRT14 knockdown.

Conclusions

Cisplatin-resistant ovarian cancer cell lines revealed elevated KRT14 expression. KRT14 knockdown reduced cisplatin resistance by lowering LRP11 expression. Therefore, KRT14 may play a crucial role in mediating cisplatin resistance in ovarian cancer.

Ginsenoside Rg6 Improves Cisplatin Resistance in Epithelial Ovarian Cancer Cells via Suppressing Fucosylation and Inducing Autophagy

Platinum-based chemotherapy remains a mainstay of clinical practice in the standard treatment of epithelial ovarian cancer (EOC). Most patients who receive this treatment, however, develop relapse and drug resistance. Ginsenoside Rg6 (G-Rg6), one of the anticarcinogenic active components in the American ginseng berry, may hold promise in the adjuvant chemotherapy of EOC. In this study, the correlation between fucosylation and cisplatin (cDDP) resistance in EOC cells was validated by gene expression profile analysis and lectin blot. We found that G-Rg6 derived from the American ginseng berry inhibits the cell viability and protein fucosylation of cDDP-resistant EOC cells. G-Rg6-induced G2/M-cell cycle arrest was proven to result from the autophagy of cDDP-resistant EOC cells. In addition, we observed that G-Rg6 initiates autophagy in cDDP-resistant EOC cells by inhibiting the GRB2-ERK1/2-mTOR axis, and that high concentration of G-Rg6 treatment leads to cell apoptosis. G-Rg6 also enhances cDDP uptake in A2780CP cells by promoting CTR1 expression and suppressing its core fucosylation. Therapies combining cDDP and G-Rg6 display higher efficacy in inhibiting the cDDP-resistant EOC cells in comparison with the sole application of cDDP, exhibiting strong potential for clinical application. G-Rg6 derived from the American ginseng berry can improve cDDP resistance in EOC cells via suppressing fucosylation and inducing autophagy, suggesting its potential in the adjuvant chemotherapy of EOC patients.

WTAP contributes to platinum resistance in high-grade serous ovarian cancer by up-regulating malic acid: insights from liquid chromatography and mass spectrometry analysis

High-grade serous cancer (HGSC) is the most prevalent and aggressive subtype of ovarian cancer. In this study, we utilized liquid chromatography and mass spectrometry analysis to investigate metabolic alterations in HGSC. Among the 1353 metabolites identified, 140 were significantly differed between HGSC and normal ovarian tissue. KEGG pathway enrichment analysis revealed 23 distinct metabolic pathways, including the alanine/aspartate/glutamate metabolism, pyruvate metabolism, biosynthesis of amino acids, and citrate cycle, etc. Of the significantly differentiated metabolites, malic acid, fumarate, and phosphoenolpyruvate were found in the citrate cycle and glycolysis. In further analysis, 22 differentially expressed genes (DEGs) of glucose metabolism were found between HGSC and normal controls. Multivariate Cox analysis of the 22 DEGs showed that ME1, ALDOC, and RANBP2 were associated with overall survival in the TCGA cohort.Bioinformatic analysis indicated WTAP is strongly correlated to the expression of ME1, which is a rate-limiting enzyme that regulates the shuttle of malic acid in mitochondria and cytoplasm. After the knockdown of WTAP in A2780 and OVCAR-3 cells, the activity of the malic enzyme decreased which led to the accumulation of malic acid and citric acid, and the reduction of pyruvate and lactic acid. In A2780 and OVCAR-3 cells, the IC50 to platinum was increased after the knockdown of WTAP. After the knockdown of WTAP, the expression of ME1 was down-regulated and the m6A modification was down-regulated in ovarian cell lines. On the SRAMP website, there were two binding sites with high m6A scores at the 5 '-UTR 177 and 970 of ME1 mRNA. WTAP contributes to the platinum resistance through regulating the conversion from aerobic glycolysis to OXPHOS by upregulating the expression of ME1.

ESM1 suppresses LncRNA GAS5/miR-23a-3p/PTEN axis to promote the cisplatin-chemotherapy resistance of ovarian cancer cells via activating the PI3K/AKT pathway

BACKGROUND

Cisplatin chemotherapy is an important treatment for advanced ovarian cancer (OC). However, the development of cisplatin resistance greatly limits the survival time of OC patients. Endothelial cell-specific molecule 1 (ESM1) has been found to be an important proto-oncogene promoting OC, but its mediating OC cisplatin resistance remains unknown.

METHODS

We used quantitative polymerase chain reaction (qPCR) to measure transcription levels of ESM1, Growth arrest specific transcript 5 (GAS5), miR-23a-3p, and Phosphatase And Tensin Homolog (PTEN). A double luciferase reporter gene assay confirmed the direct binding of GAS5 to miR-23a-3p and miR-23a-3p to PTEN mRNA. The effects of ESM1, GAS5, miR-23a-3p, and PTEN on OC cisplatin resistance were tested with an Half Maximal Inhibitory Concentration (IC50) assay. Flow cytometry was used to assess the effects of ESM1, GAS5, and miR-23a-3p on cisplatin-induced OC apoptosis. Changes in apoptosis-related proteins and PI3K/AKT-related proteins were analyzed with western blot (WB).

RESULTS

ESM1 inhibits the levels of GAS5 and PTEN but increases miR-23a-3p. ESM1 and miR-23a-3p promote OC cisplatin resistance. GAS5 and miR-23a-3p promote cisplatin sensitivity for OC cells. Moreover, the main molecular mechanism is the ESM1/GAS5/miR-23a-3p/PTEN/PI3K/Akt signaling axis.

CONCLUSION

ESM1 promotes OC cisplatin resistance by activating the Phosphoinositide-3-Kinase (PI3K)/AKT Serine/Threonine Kinase (Akt) signaling pathway through the GAS5/miR-23a-3p/PTEN signaling axis. This suggests that prescriptive ESM1 regulates key downstream molecular mechanisms via non-coding RNA and can be used before neoadjuvant chemotherapy in OC is initiated.

Inhibition of homologous recombination repair by Mirin in ovarian cancer ameliorates carboplatin therapy response in vitro

Chemoresistance poses one of the most significant challenges of cancer therapy. Carboplatin (CbPt) is one of the most used chemotherapeutics in ovarian cancer (OVC) treatment. MRE11 constitutes a part of homologous recombination (HR), which is responsible for the repair of CbPt-induced DNA damage, particularly DNA crosslinks. The study's main aim was to address the role of HR in CbPt chemoresistance in OVC and to evaluate the possibility of overcoming CbPt chemoresistance by Mirin-mediated MRE11 inhibition in an OVC cell line. Lower expression of MRE11 was associated with better overall survival in a cohort of OVC patients treated with platinum drugs (TCGA dataset, P < 0.05). Using in vitro analyses, we showed that the high expression of HR genes drives the CbPt chemoresistance in our CbPt-resistant cell line model. Moreover, the HR inhibition by Mirin not only increased sensitivity to carboplatin (P < 0.05) but also rescued the sensitivity in the CbPt-resistant model (P < 0.05). Our results suggest that MRE11 inhibition with Mirin may represent a promising way to overcome OVC resistance. More therapy options will ultimately lead to better personalized cancer therapy and improvement of patients' survival.

Precision Medicine in High-Grade Serous Ovarian Cancer: Targeted Therapies and the Challenge of Chemoresistance

The poor prognosis for high-grade serous ovarian cancer (HGSOC), the dominant subtype of ovarian cancer, reflects its aggressive nature, late diagnosis, and the highest mortality rate among all gynaecologic cancers. Apart from late diagnosis, the main reason for the poor prognosis and its unsuccessful treatment is primarily the emergence of chemoresistance to carboplatin. Although there is a good response to primary treatment, the disease recurs in 80% of cases, at which point it is largely resistant to carboplatin. The introduction of novel targeted therapies in the second decade of the 21st century has begun to transform the treatment of HGSOC, although their impact on overall survival remains unsatisfactory. Targeting the specific pathways known to be abnormally activated in HGSOC is especially difficult due to the molecular diversity of its subtypes. Moreover, a range of molecular changes are associated with acquired chemoresistance, e.g., reversion of BRCA1 and BRCA2 germline alleles. In this review, we examine the advantages and disadvantages of approved targeted therapies, including bevacizumab, PARP inhibitors (PARPis), and treatments targeting cells with neurotrophic tyrosine receptor kinase (NTRK), B-rapidly accelerated fibrosarcoma (BRAF), and rearranged during transfection (RET) gene alterations, as well as antibody-drug conjugates. Additionally, we explore promising new targets under investigation in ongoing clinical trials, such as immune checkpoint inhibitors, anti-angiogenic agents, phosphatidylinositol-3-kinase (PI3K) inhibitors, Wee1 kinase inhibitors, and ataxia telangiectasia and Rad3-related protein (ATR) inhibitors for platinum-resistant disease. Despite the development of new targeted therapies, carboplatin remains the fundamental medicine in HGSOC therapy. The correct choice of treatment strategy for better survival of patients with advanced HGSOC should therefore include a prediction of patients' risks of developing chemoresistance to platinum-based chemotherapy. Moreover, effective targeted therapy requires the selection of patients who are likely to derive clinical benefit while minimizing potential adverse effects, underscoring the essence of precision medicine.

Self-assembled HO-1i-Pt(IV) nanomedicine targeting p38/MAPK and MDR pathways for cancer chemo-immunotherapy

Platinum(II)-based antitumor drugs are widely used in clinics but limited by severe side effects and resistance. Multi-target Platinum(IV) complexes are emerging as ideal alternatives. Heme oxygenase-1 (HO-1) works as a rate-limiting step in heme degradation and is overexpressed in malignant tumors. Herein, HO-1i-based Platinum(IV) prodrugs are prepared and candidate complex 15 is further developed into self-assembled nanoparticles (15-NPs). 15 and 15-NPs significantly increase cytotoxicity, particularly in HepG2 (74.77- and 96.14-fold increases) and A549cisR (38.6- and 47.24-fold increases), while reducing toxicity towards normal cells compared to cisplatin. In vitro experiments show 15 and 15-NPs activated multiple pathways, including p38/MAPK- and MDR-related proteins, achieving multi-target synergistic chemosensitization and anti-resistance, further verified by RNA-sequencing analysis. In vivo tests demonstrate that 15 and 15-NPs efficiently inhibit tumor growth and systemic toxicity, especially 15-NPs with optimal tumor-inhibition rate and survival (80% and 100%), superior to cisplatin (40% and 50%), attributing to its extra endocytosis, EPR effect, and precisely tumor-targeted release besides the advantage of a free HO-1i-Pt(IV) prodrug. Additionally, 15 and 15-NPs distinctly regulate T-cell and macrophage functions, thereby exhibiting a chemoimmuno-combined action. This study highlights that multi-functional Platinum(IV) prodrug target-delivered to tumors via carrier-free nanoparticles may represent an effective modality for improving cancer therapy.

Tasquinimod promotes the sensitivity of ovarian cancer cells to cisplatin by down-regulating the HDAC4/p21 pathway

To investigate whether Tasquinimod can influence cisplatin resistance in drug-resistant ovarian cancer (OC) cell lines by regulating histone deacetylase 4 (HDAC4) or p21, we explored its effects on the cell cycle, and associated mechanisms. RT-PCR and Western blot analyses, flow cytometry, CCK8 assay, and immunofluorescence were utilized to investigate the effects of Tasquinimod on gene expression, cell cycle, apoptosis, viability, and protein levels in OC cells. The results showed that Tasquinimod inhibited cell viability and promoted apoptosis in SKOV3/DDP (cisplatin) and A2780/DDP cells more effectively than DDP alone. In combination with cisplatin, Tasquinimod further enhanced cell apoptosis and reduced cell viability in these cell lines, an effect that could be reversed following HDAC4 overexpression. Tasquinimod treatment down-regulated HDAC4, Bcl-2, and cyclin D1, and CDK4 expression and up-regulated the cleaved-Caspase-3, and p21 expression in SKOV3/DDP and A2780/ DDP cells. Additionally, Tasquinimod inhibited DDP resistance in OC/DDP cells. These effects were similarly observed in OC mouse models treated with Tasquinimod. In conclusion, Tasquinimod can improve OC cells' sensitivity to DDP by down-regulating the HDAC4/p21 axis, offering insights into potential strategies for overcoming cisplatin resistance in OC.

RETRACTED: Refining molecular subtypes and risk stratification of ovarian cancer through multi-omics consensus portfolio and machine learning

Ovarian cancer (OC), known for its pronounced heterogeneity, has long evaded a unified classification system despite extensive research efforts. This study integrated five distinct multi-omics datasets from eight multicentric cohorts, applying a combination of ten clustering algorithms and ninety-nine machine learning models. This methodology has enabled us to refine the molecular subtyping of OC, leading to the development of a novel Consensus Machine Learning-driven Signature (CMLS). Our analysis delineated two prognostically significant cancer subtypes (CS), each marked by unique genetic and immunological signatures. Notably, CS1 is associated with an adverse prognosis. Leveraging a subtype classifier, we identified five key genes (CTHRC1, SPEF1, SCGB3A1, FOXJ1, and C1orf194) instrumental in constructing the CMLS. Patients classified within the high CMLS group exhibited a poorer prognosis and were characterized by a "cold tumor" phenotype, indicative of an immunosuppressive microenvironment rich in MDSCs, CAFs, and Tregs. Intriguingly, this group also presented higher levels of tumor mutation burden (TMB) and tumor neoantigen burden (TNB), factors that correlated with a more favorable response to immunotherapy compared to their low CMLS counterparts. In contrast, the low CMLS group, despite also displaying a "cold tumor" phenotype, showed a favorable prognosis and a heightened responsiveness to chemotherapy. This study's findings underscore the potential of targeting immune-suppressive cells, particularly in patients with high CMLS, as a strategic approach to enhance OC prognosis. Furthermore, the redefined molecular subtypes and risk stratification, achieved through sophisticated multi-omics analysis, provide a framework for the selection of therapeutic agents.

Comprehensive bioinformatics analysis of co-mutation of FLG2 and TP53 reveals prognostic effect and influences on the immune infiltration in ovarian serous cystadenocarcinoma

Background

Ovarian cancer remains one of the most lethal gynecological malignancies, characterized by late-stage diagnosis and high rates of recurrence. The present study aims to explore the prognostic and immunological implications of FLG2 and TP53, the two genes exhibiting a high mutation frequency across various cancer types, in the context of ovarian serous cystadenocarcinoma (OV).

Methods

The study systematically analyzed and discussed the potential implications of co-mutation of FLG2 and TP53 on prognosis and immune response using a cohort of 585 ovarian cancer samples. The differentially expressed genes (DEGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on 300 ovarian cancer samples with RNA sequencing (RNA-seq) data.

Results

The co-mutation of FLG2 and TP53 was identified in the 585 ovarian cancer cohort, and the group with co-mutation exhibited improved outcomes in terms of overall survival (OS), progression-free survival (PFS), and disease-specific survival (DSS). Additionally, the co-mutation (FLG2 +/TP53 +) group demonstrated higher scores in tumor mutation burden (TMB) comparing to that of the other three groups. The score of microsatellite instability (MSI) in the co-mutant group was only higher than that of the co-wild-type (FLG2 -/TP53 -). A total of 327 DEGs were identified in both the co-mutation and non-co-mutation (NCM) groups using limma analysis in the subgroup of 300 patients with RNA-seq data. Subsequent KEGG analysis revealed that these DEGs were implicated in various biological processes, including thermogenesis, Parkinson's disease (PD), and oxidative phosphorylation signaling pathways. Additionally, the co-mutation group exhibited elevated levels of various immune cells. Furthermore, a nomogram with high predictive accuracy was developed by integrating co-mutation status with clinical characteristics.

Conclusions

In the context of OV, the concurrent mutation of FLG2 and TP53 not only induces immune activation, but also helps identify a subset of patients with a more favorable prognosis.

Host Defense Peptide Mimics Synergize with Pt(IV) Prodrugs for Surmounting Cisplatin Resistance via Selective Cancer Membrane Disruption

Drug resistance has emerged as a great challenge for achieving satisfactory therapeutic efficacy in platinum-based chemotherapy. Specifically, we synthesized a series of host defense peptide mimics with different degrees of polymerization (DP), i.e., poly(ethylene glycol)-poly(2-azepane ethyl methacrylate) (PEG45-PAEMAn, n = 8, 20, 43, 87, and 183), which displayed DP- and pH-dependent plasma membrane-disruptive capability and antitumor activity. Among these, PEG45-PAEMA43 exhibited the highest cytotoxicity at tumor acidity (pH 6.7), selectivity index, and in vivo antitumor activity, and was selected to encapsulate the hydrophobic Pt(IV) prodrug to form the PEG-PAEMA-Pt(IV) nanoprodrug. The nanoprodrug boosted the membrane-disruptive capability and antitumor activity of A549 and cisplatin-resistant A549/DDP cells at tumor acidity. Notably, it exhibited a much higher cellular uptake for A549/DDP cells and in vivo antitumor activity than PEG-PAEMA or cisplatin alone. This indicated that the PEG-PAEMA-Pt(IV) nanoprodrug could break the drug diffusion barrier posed by the cell membrane and disable even reverse efflux resistance.

A Novel Insight into the Role of Obesity-Related Adipokines in Ovarian Cancer-State-of-the-Art Review and Future Perspectives

Ovarian cancer (OC) is one of the most fatal gynecological neoplasms. Meta-analyses have shown that the relationship between body mass index (BMI) and ovarian cancer incidence was detected in some types of ovarian cancer. Chronic inflammation and excessive accumulation of free fatty acids are key adipose tissue-derived factors initiating cancer development. Cancer cells transform adipose-derived stem cells into cancer-associated adipocytes, which produce adipokines and interleukins. It was revealed that adipokines exert a pleiotropic role in ovarian cancer pathogenesis. Chemerin presents both pro-cancer and anti-cancer action in ovarian cancer development. Chemerin induces angiogenesis and increases programmed death ligand-1 (PD-L1) expression, leading to enhanced proliferation and migration of OC cells. Apelin impacts cancer cell migration and acts as a mitogenic factor. Moreover, apelin exerts influence on lipid uptake into cancer cells and accelerates fatty acid oxidation, which provides energy for cancer cells. Visfatin induces matrix metallopeptidase 2 (MMP2) expression involved in extracellular matrix degradation and suppresses claudin 3 and 4 expression. Visfatin also induces a shift to anaerobic glucose metabolism and influences poly-ADP ribose polymerase (PARP). Resistin induces MMP2 and vascular endothelial growth factor (VEGF) expression and contributes to cisplatin-resistance development. A substantial body of evidence indicates that antagonists of adipokines mitigate OC progression, and adipokines are gaining gradual recognition as a potential therapeutic aim in ovarian cancer targeted therapy.

In vitro analysis of the molecular mechanisms of ursolic acid against ovarian cancer

Ovarian cancer is one of most common gynaecologic malignancy and ranks third in cancer-related deaths among women. Ursolic acid (UA) is a pharmacologically active pentacyclic triterpenoid isolated from a large variety of vegetables, fruits and many traditional medicinal plants. However, the mechanism of action of UA in inhibiting the proliferation of ovarian cancer cells remains unclear. Consequently, this experiment was designed to elucidate the mechanism of action of UA in inhibiting the proliferation of ovarian cancer cells in greater detail.The results indicated that UA was capable of effectively inhibiting the proliferation, migration, and colony formation of ovarian cancer cells.UA was observed to up-regulate Bcl-2-associated X protein(BAX)and cysteinyl aspartate specific proteinase 3 (Caspase3) expression and down-regulating B-cell lymphoma-2(Bcl-2) expression.Meanwhile, UA up-regulated Sequestosome 1(p62)expression and down-regulated coiled-coil, moesin-like BCL2-interacting protein(Becline1), microtubule-associated proteins light chain 3(LC3), Phosphoinositide 3-Kinase(PI3K), andProtein Kinase B( AKT) expression, thus effectively inhibiting autophagy in ovarian cancer cells.Furthermore, UA upregulated pancreatic ER kinase (PKR)-like ER kinase (PERK), eukaryotic translation initiation factor 2 A(eIF2α), and The C/EBP Homologous Protein(CHOP) expression.In addition UA upregulates PERK, eIF2α, and CHOP expression and effectively promotes endoplasmic reticulum stress(ERS).In conclusion, UA can inhibit ovarian cancer cell proliferation, migration, colony formation, and may inhibit tumor cell autophagy by promoting tumor cell ERS, and ultimately promote ovarian cancer cell apoptosis.

Clinical Impact of Olaparib for Platinum-Sensitive Recurrent Ovarian Cancer

Background/Objectives: Olaparib, a poly ADP ribose polymerase inhibitor, has been effective in prolonging progression-free survival in platinum-sensitive recurrent ovarian cancer. The clinicopathological factors that predict a favorable prognosis remain unclear. Therefore, we retrospectively analyzed the prognostic effect of clinicopathological factors in the patients treated with olaparib for platinum-sensitive recurrent ovarian cancer. Methods: A total of 16 patients were treated with olaparib from 2018 to 2023. We categorized these patients into the responder (five cases who had not relapsed within 2 years) and non-responder groups (11 cases who had relapsed within 2 years). Clinical factors, including age, number of platinum drug courses, platinum-free interval, and CA125 value before olaparib treatment, were compared between the responder and non-responder groups. Results: The age of the responder group was significantly younger than that of the non-responder group (52 vs. 69 years old, p = 0.02). The CA125 value of the responder group was significantly lower than that of the non-responder group (14.2 vs. 82.7 U/mL, p = 0.02). Conclusions: The good predictive factors that enabled continued olaparib administration without recurrence were younger age and a lower CA125 value before olaparib treatment. The younger group (<65 years old) and the low CA125 value group (<20 U/mL) in PSR may be treated with olaparib for a long period, suppressing disease progression. Providing this information to patients with PSR may help in decision-making regarding performing maintenance therapy with olaparib.

Efficacy and Safety of Low-Dose Lenvatinib and Toripalimab in Patients With Recurrent Platinum-Resistant Ovarian Cancer: Study Protocol of a Multicenter, Open-Label, Single-Arm, Phase II Clinical Trial

Purpose

Therapeutic options for patients with platinum-resistant ovarian cancer (PROC) remain a major unmet need. PROC patients with multiple recurrences are unable to continue highly toxic treatment after prior multiple lines of systemic therapy. Chemotherapy-free option lenvatinib plus anti-programmed cell death protein-1 (PD-1) combination therapy has shown promising results in several malignancies including ovarian cancer, but the toxicity of a high starting dose of lenvatinib is also notable and needs to be improved. Our previous pilot study indicated that a reduced starting dose of lenvatinib may maintain comparable anti-tumor activity with favorable safety in heavily pre-treated ovarian cancer. This study is designed to further validate the efficacy and safety of the combination therapy of low-dose lenvatinib and PD-1 inhibitor toripalimab in patients with recurrent PROC.

Study Design and Methods

The study is designed as a multicenter, open-label, single-arm, prospective phase II study. Patients with recurrent epithelial ovarian cancer who have disease progression either during or within 6 months after completion of platinum-based therapy will be included. A total of 69 participants will receive low-dose lenvatinib (8 mg or 12 mg, daily, orally, based on patient's body weight) and toripalimab (240 mg, every 21 days, intravenously). Treatment will continue until the development of unacceptable toxicity or disease progression. The primary endpoint is the progression-free survival. The secondary endpoints include objective response rate, duration of response, disease control rate, overall survival, toxicity and patients' quality of life. Exploratory objectives aim to identify biomarkers and molecular signatures for predicting response or prognosis.

LncRNA MIR17HG drives cisplatin resistance partially via miR-138-5p/AKAP9 axis in cholangiocarcinoma

OBJECTIVES

This study aims to discover the role of lncRNA MIR17HG, referred to as MIR17HG, in cisplatin resistance for cholangiocarcinoma (CCA).

METHODS

QRT-PCR was conducted to measure the expression of MIR17HG in cisplatin-resistant/sensitive CCA cells and clinical CCA specimens. Log-rank test was used to analyze the survival curve. Cck8-assay and flow cytometry were employed to detect the sensitivity of CCA cells to cisplatin and the apoptosis rate following different treatments, respectively. The next-generation sequencing was carried out to get gene transcripts after silencing MIR17HG in HCCC-9810 cells. The LncBase database was used to predict the target miRNA of MIR17HG, and MS2 RIP assay and dual luciferase assay were conducted to confirm their binding. MiRwalk database and the RNA sequencing data were utilized to screen the key genes regulated by MIR17HG/miR-138-5p axis and a dual luciferase assay was performed to confirm the binding site of miR-138-5p with AKAP9. Immunoblotting was further employed to give assistant evidence. Rescue experiments were performed to observe the function of miR-138-5p and AKAP9 in MIR17HG-induced cisplatin resistance.

RESULTS

MIR17HG overexpression predicts cisplatin resistance and poor prognosis in CCA. MIR17HG could bind with miR-138-5p to release AKAP9, thereby inhibiting cisplatin-induced apoptosis and promoting cisplatin resistance in CCA. MIR17HG silencing in CCA cells leads to expression alteration of genes, which are enriched in platinum resistance-related pathways.

CONCLUSIONS

LncRNA MIR17HG regulates platinum resistance-associated genes and promotes cisplatin resistance partially via the miR-138-5p/AKAP9 axis by inhibiting cisplatin-induced apoptosis in CCA.

Rucaparib versus chemotherapy for treatment of relapsed ovarian cancer with deleterious BRCA1 or BRCA2 mutation (ARIEL4): final results of an international, open-label, randomised, phase 3 trial

BACKGROUND

In the ARIEL4 trial of rucaparib versus standard-of-care chemotherapy in patients with relapsed BRCA-mutated ovarian carcinoma, the primary endpoint was met, showing improved investigator-assessed progression-free survival with rucaparib. Here, we present the final overall survival analysis of the trial and other post-progression outcomes.

METHODS

This open-label, randomised, controlled phase 3 trial was done at 64 hospitals and cancer centres in 12 countries, including Brazil, Canada, Czech Republic, Hungary, Israel, Italy, Poland, Russia, Spain, Ukraine, the UK, and the USA. Eligible patients were women aged 18 or older with BRCA1 or BRCA2-mutated ovarian carcinoma and had received at least two previous chemotherapy regimens. Patients had to have evaluable disease as per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) criteria and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients were randomly assigned (2:1) using an interactive response technology and block randomisation (block size of six) and stratified by progression-free interval after the most recent platinum-containing therapy to receive oral rucaparib (600 mg twice daily administered in 28-day cycles) or chemotherapy on the basis of platinum-sensitivity status. In the chemotherapy group, patients with platinum-resistant disease (progression-free interval ≥1 to <6 months) or partially platinum-sensitive disease (progression-free interval ≥6 to <12 months) received weekly paclitaxel (starting dose 60-80 mg/m2 on days 1, 8, and 15). Patients with fully platinum-sensitive disease (progression-free interval ≥12 months) received the investigator's choice of platinum-based chemotherapy (single-agent cisplatin or carboplatin, or platinum-doublet chemotherapy), in 21-day or 28-day cycles. The primary endpoint (previously reported) was investigator-assessed progression-free survival, assessed in the efficacy population (all randomly assigned patients with deleterious BRCA1 or BRCA2 mutations without reversion mutations) and in the intention-to-treat population (all randomly assigned patients). Overall survival was a prespecified secondary endpoint and was analysed in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of assigned study treatment. The cutoff date was April 10, 2022. This study is registered with ClinicalTrials.gov, NCT02855944; enrolment is complete and the study is closed.

FINDINGS

Between March 1, 2017, and Sept 24, 2020, 349 eligible patients were randomly assigned to receive rucaparib (n=233) or chemotherapy (n=116). 332 (95%) of 349 patients were white and 17 (5%) patients were other or of unknown race. In the chemotherapy group, 80 (69%) of 116 patients crossed over to receive rucaparib. Median follow-up was 41·2 months (IQR 37·8-44·6). At data cutoff for this final analysis (April 10, 2022), 244 (70%) of 349 patients had died: 167 (72%) of 233 in the rucaparib group and 77 (66%) of 116 in the rucaparib group. Median overall survival was 19·4 months (95% CI 15·2-23·6) in the rucaparib group versus 25·4 months (21·4-27·6) in the chemotherapy group (hazard ratio 1·3 [95% CI 1·0-1·7], p=0·047). No new safety signals were observed, including during crossover to rucaparib. The most common grade 3-4 adverse events across treatment groups included anaemia or decreased haemoglobin (reported in 59 [25%] of 232 patients in the rucaparib group and seven [6%] of 113 in the chemotherapy group), and neutropenia or decreased neutrophil count (in 26 [11%] of 232 in the rucaparib group and 16 [14%] of 113 patients in the chemotherapy group). Serious adverse events were reported in 66 (28%) of 232 patients in the rucaparib group and 14 (12%) of 113 patients in the chemotherapy group. Ten treatment-related deaths were reported in the rucaparib group, two of which were linked to judged to be related to rucaparib (cardiac disorder and myelodysplastic syndrome), and one death related to treatment was reported in the chemotherapy group, with no specific cause linked to the treatment.

INTERPRETATION

These data highlight the need for a better understanding of the most appropriate treatment for patients who have progressed on a poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor, and the optimal sequencing of chemotherapy and PARP inhibitors in advanced ovarian cancer.

FUNDING

Clovis Oncology.

Long Non-Coding RNAs in Ovarian Cancer: Mechanistic Insights and Clinical Applications

Background/Objectives: Ovarian cancer is a leading cause of gynecological cancer mortality worldwide, often diagnosed at advanced stages due to vague symptoms and the lack of effective early detection methods. Long non-coding RNAs (lncRNAs) have emerged as key regulators in cancer biology, influencing cellular processes such as proliferation, apoptosis, and chemoresistance. This review explores the multifaceted roles of lncRNAs in ovarian cancer pathogenesis and their potential as biomarkers and therapeutic targets. Methods: A comprehensive literature review was conducted to analyze the structural and functional characteristics of lncRNAs and their contributions to ovarian cancer biology. This includes their regulatory mechanisms, interactions with signaling pathways, and implications for therapeutic resistance. Advanced bioinformatics and omics approaches were also evaluated for their potential in lncRNA research. Results: The review highlights the dual role of lncRNAs as oncogenes and tumor suppressors, modulating processes such as cell proliferation, invasion, and angiogenesis. Specific lncRNAs, such as HOTAIR and GAS5, demonstrate significant potential as diagnostic biomarkers and therapeutic targets. Emerging technologies, such as single-cell sequencing, provide valuable insights into the tumor microenvironment and the heterogeneity of lncRNA expression. Conclusions: LncRNAs hold transformative potential in advancing ovarian cancer diagnosis, prognosis, and treatment. Targeting lncRNAs or their associated pathways offers promising strategies to overcome therapy resistance and enhance personalized medicine. Continued research integrating omics and bioinformatics will be essential to unlock the full clinical potential of lncRNAs in ovarian cancer management.

Optimizing Therapeutics for Intratumoral Cancer Treatments: Antiproliferative Vanadium Complexes in Glioblastoma

Glioblastoma, an aggressive cancer, is difficult to treat due to its location, late detection, drug resistance, and poor absorption of chemotherapeutics. Intratumoral drug administration offers a promising potential treatment alternative with localized delivery and minimal systemic toxicity. Vanadium(V) coordination complexes, incorporating Schiff base and catecholate ligands, have shown effects as antiproliferative agents with tunable efficacy and reactivity, stability, steric bulk, hydrophobicity, uptake, and toxicity optimized for the intratumoral administration vehicle. A new series of oxovanadium(V) Schiff base-catecholate complexes were synthesized and characterized using nuclear magnetic resonance (NMR), UV-Vis, and infrared spectroscopy and mass spectrometry. Stability under physiological conditions was assessed via UV-Vis spectroscopy, and the antiproliferative activity was evaluated in T98G glioblastoma and SVG p12 normal glial cells using viability assays. The newly synthesized [VO(3-tBuHSHED)(TIPCAT)] complex was more stable (t1/2 ~4.5 h) and had strong antiproliferative activity (IC50 ~1.5 µM), comparing favorably with the current lead compound, [VO(HSHED)(DTB)]. The structural modifications enhanced stability, hydrophobicity, and steric bulk through substitution with iso-propyl and tert-butyl groups. The improved properties were attributed to steric hindrance associated with the new Schiff base and catecholato ligands, as well as the formation of non-toxic byproducts upon degradation. The [VO(3-tBuHSHED)(TIPCAT)] complex emerges as a promising candidate for glioblastoma therapy by demonstrating enhanced stability and a greater selectivity, which highlights the role of strategic ligand design in developing localized therapies for the treatment of resistant cancers. In reporting the new class of compounds effective against T98G glioblastoma cells, we describe the generally desirable properties that potential drugs being developed for intratumoral administration should have.

CT-based radiomics predicts HRD score and HRD status in patients with ovarian cancer

Introduction

This study predicted HRD score and status based on intra- and peritumoral radiomics in patients with ovarian cancer (OC) for better guiding the use of PARPi in clinical.

Methods

A total of 106 and 95 patients with OC were included between January 2022 and November 2023 for predicting HRD score and status, respectively. Radiomics features were extracted and quantitatively analyzed from intra- and peri-tumor regions in the CT image. Radiomics signatures (RSs) were built based on features from intra- and peri-tumor regions for predicting HRD score and status alone or in combination. Subject working characteristics (ROC) area under the curve (AUC), sensitivity (SEN), and specificity (SPE) were calculated as comparative metrics.

Results

For predicting HRD score, 4 and 2 features were selected as the most important predictors from the intra- and peritumoral regions, respectively. For predicting HRD status, 4 features from the intratumoral region and 2 from the peritumoral region were identified as the most important predictors. Radiomics nomograms created by combining RSs and important clinical factors showed good predictive results with AUCs of 0.852 (95% confidence interval [CI]: 0.765-0.938, SEN = 0.907, SPE = 0.655) and 0.781 (95% CI: 0.621-0.941, SEN = 0.688, SPE = 0.833) in the training and validation cohort for predicting HRD score, respectively; with AUCs of 0.874 (95% CI: 0.790-0.957, SEN = 0.765, SPE = 0.867) and 0.824 (95% CI: 0.663-0.985, SEN = 0.762, SPE = 0.800) in the training and validation cohort for predicting HRD status, respectively.

Discussion

Calibration curves and decision curve analysis (DCA) confirmed potential clinical usefulness of our nomograms. Our findings suggest that radiomics features derived from the CT image of OC have the potential to predict HRD score and status, and the developed nomograms can enrich the range of applicable population of PARPi, prolong progression-free survival and provide personalized treatment for OC patients.

Opportunities for predictive proteogenomic biomarkers of drug treatment sensitivity in epithelial ovarian cancer

Genomic analysis has played a significant role in the identification of driver mutations that are linked to disease progression and response to drug treatment in ovarian cancer. A prominent example is the stratification of epithelial ovarian cancer (EOC) patients with homologous recombination deficiency (HRD) characterized by mutations in DNA damage repair genes such as BRCA1/2 for treatment with PARP inhibitors. However, recent studies have shown that some epithelial ovarian tumors respond to PARP inhibitors irrespective of their HRD or BRCA mutation status. An exclusive focus on the genome overlooks the significant insight that can be gained from other biological analytes, including proteins, which carry out cellular functions. Proteogenomics is the integration of genomics, transcriptomics, epigenomics and proteomics data. This review paper provides novel insight into the role of proteogenomics as an analytical approach to identify predictive biomarkers of drug treatment response in epithelial ovarian cancer. Proteogenomic analysis can facilitate the identification of predictive biomarkers of drug treatment response, consequently greatly improving the stratification of patients with EOC for treatment towards a goal of personalized medicine.

Processed Products of Aconitum soongaricum Stapf. Inhibit the Growth of Ovarian Cancer Cells In vivo via Regulating the PI3K/AKT Signal Pathway

INTRODUCTION/OBJECTIVE

The alkaloids of songorine, aconitine, and benzoylaconitine, as the processed products of Aconitum soongaricum Stapf., can significantly inhibit the migration and invasion of ovarian cancer cells in vitro. Herein, we studied the in vivo role and mechanism of these natural products in processed A. soongaricum Stapf.

METHODS

A xenograft tumor model was constructed. Tumor volumes and weights were calculated. HE staining assessed the histopathological changes of tumors. Inflammatory factors were detected using ELISA. Gene and protein expressions of E-cadherin, N-cadherin, PIK3CA, and AKT1 proteins were measured using RT-qPCR and immunohistochemistry. Protein expressions of E-cadherin, N-cadherin, PIK3CA, AKT1, p-PIK3CA, and p- AKT1 proteins were detected using western blot analysis.

RESULTS

Songorine, aconitine, and benzoylaconine significantly inhibited the growth of tumors as evidenced by decreased tumor volume and weight. The extent and scope of tumor cell necrosis were less in the songorine group compared to the vehicle group. Songorine, aconitine, and benzoylaconine significantly reduced IL-6, IL-1β, and TNF-α levels. Furthermore, songorine, aconitine, and benzoylecgonine induced down-regulation of N-cadherin and AKT1 mRNA in comparison to the vehicle group. Meanwhile, songorine, aconitine, and benzoylaconine also significantly reduced N-cadherin, p-PIK3CA, and p-AKT1 proteins, while upregulating E-cadherin protein expression in comparison to the vehicle group. These effects were further enhanced when combined with the PI3K inhibitor LY294002.

CONCLUSION

Songorine, aconitine, and benzoylaconine may inhibit ovarian cancer growth in vivo by blocking the PI3K/AKT signaling pathway. Our findings may provide evidence for the clinical application of the processed products of Aconitum soongaricum Stapf. in ovarian cancer treatment.

KLF4 activates LATS2 to promote cisplatin sensitivity in ovarian cancer through DNA damage

We aimed to investigate the role of large tumor suppressor kinase 2 (LATS2) in cisplatin (DDP) sensitivity in ovarian cancer. Bioinformatic analysis explored LATS2 expression, pathways, and regulators. Quantitative reverse transcription-PCR measured LATS2 and KLF4 mRNA levels. Dual-luciferase and chromatin immunoprecipitation assays confirmed their binding relationship. Cell viability, half maximal inhibitory concentration (IC 50 ) values, cell cycle, and DNA damage were assessed using CCK-8, flow cytometry, and comet assays. Western blot analyzed protein expression. The effect of LATS2 on the sensitivity of ovarian cancer to DDP was verified in vivo . LATS2 and KLF4 were downregulated in ovarian cancer, with LATS2 enriched in cell cycle, DNA replication, and mismatch repair pathways. KLF4, an upstream regulator of LATS2, bound to its promoter. Overexpressing LATS2 increased G1-phase cells, reduced cell viability and IC 50 values, and induced DNA damage. Silencing KLF4 alone showed the opposite effect on LATS2 overexpression. Knocking out LATS2 reversed the effects of KLF4 overexpression on cell viability, cell cycle, IC 50 values, and DNA damage in ovarian cancer cells. Inhibiting LATS2 inactivated the Hippo-YAP signaling pathway. In vivo experiments showed that overexpression of LATS2 enhanced the sensitivity of ovarian cancer to DDP. KLF4 activates LATS2 via DNA damage to enhance DDP sensitivity in ovarian cancer, providing a potential target for improving treatment outcomes.

A multi-view contrastive learning and semi-supervised self-distillation framework for early recurrence prediction in ovarian cancer

OBJECTIVE

This study presents a novel framework that integrates contrastive learning and knowledge distillation to improve early ovarian cancer (OC) recurrence prediction, addressing the challenges posed by limited labeled data and tumor heterogeneity.

METHODS

The research utilized CT imaging data from 585 OC patients, including 142 cases with complete follow-up information and 125 cases with unknown recurrence status. To pre-train the teacher network, 318 unlabeled images were sourced from public datasets (TCGA-OV and PLAGH-202-OC). Multi-view contrastive learning (MVCL) was employed to generate multi-view 2D tumor slices, enhancing the teacher network's ability to extract features from complex, heterogeneous tumors with high intra-class variability. Building on this foundation, the proposed semi-supervised multi-task self-distillation (Semi-MTSD) framework integrated OC subtyping as an auxiliary task using multi-task learning (MTL). This approach allowed the co-training of a student network for recurrence prediction, leveraging both labeled and unlabeled data to improve predictive performance in data-limited settings. The student network's performance was assessed using preoperative CT images with known recurrence outcomes. Evaluation metrics included area under the receiver operating characteristic curve (AUC), accuracy (ACC), sensitivity (SEN), specificity (SPE), F1 score, floating-point operations (FLOPs), parameter count, training time, inference time, and mean corruption error (mCE).

RESULTS

The proposed framework achieved an ACC of 0.862, an AUC of 0.916, a SPE of 0.895, and an F1 score of 0.831, surpassing existing methods for OC recurrence prediction. Comparative and ablation studies validated the model's robustness, particularly in scenarios characterized by data scarcity and tumor heterogeneity.

CONCLUSION

The MVCL and Semi-MTSD framework demonstrates significant advancements in OC recurrence prediction, showcasing strong generalization capabilities in complex, data-constrained environments. This approach offers a promising pathway toward more personalized treatment strategies for OC patients.

Therapeutic Chemoresistance in Ovarian Cancer: Emerging Hallmarks, Signaling Mechanisms and Alternative Pathways

Ovarian cancer is the fifth leading cause of mortality and the most lethal gynecologic malignancy among females. It may arise from atypical borderline tumors (Type I) or serous tubal intraepithelial carcinoma (Type II). The diagnosis of cancer at its early stages is difficult because of non-specific symptoms, most patients are diagnosed at the advanced stage. Several drugs and therapeutic strategies are available to treat ovarian cancer such as surgery, chemotherapy, neoadjuvant therapy, and maintenance therapy. However, the cancer cells have developed resistance to a number of available therapies causing treatment failure. This emerging chemoresistance in ovarian cancer cells is becoming an obstacle due to alterations in multiple cellular processes. These processes involve altered drug target response, drug pumps, detoxification systems, lower sensitivity to apoptosis, and altered proliferation, and are responsible for developing resistance to anticancer medicines. Various research reports have evidenced that these altered processes might play a role in the emergence of resistance. This review addresses the recent advances in understanding the underlying mechanisms of ovarian cancer resistance and covers sophisticated alternative pathways to overcome these resistance mechanisms in patients.

Development of a Prognostic Risk Model Based on Oxidative Stress-related Genes for Platinum-resistant Ovarian Cancer Patients

INTRODUCTION

Ovarian Cancer (OC) is a heterogeneous malignancy with poor outcomes. Oxidative stress plays a crucial role in developing drug resistance. However, the relationships between Oxidative Stress-related Genes (OSRGs) and the prognosis of platinum-resistant OC remain unclear. This study aimed to develop an OSRGs-based prognostic risk model for platinum- resistant OC patients.

METHODS

Gene Set Enrichment Analysis (GSEA) was performed to determine the expression difference of OSRGs between platinum-resistant and -sensitive OC patients. Cox regression analyses were used to identify the prognostic OSRGs and establish a risk score model. The model was validated by using an external dataset. Machine learning was used to determine the prognostic OSRGs associated with platinum resistance. Finally, the biological functions of selected OSRG were determined via in vitro cellular experiments.

RESULTS

Three gene sets associated with oxidative stress-related pathways were enriched (p < 0.05), and 105 OSRGs were found to be differentially expressed between platinum-resistant and - sensitive OC (p < 0.05). Twenty prognosis-associated OSRGs were identified (HR: 0:562-5.437; 95% CI: 0.319-20.148; p < 0.005), and seven independent OSRGs were used to construct a prognostic risk score model, which accurately predicted the survival of OC patients (1-, 3-, and 5-year AUC=0.69, 0.75, and 0.67, respectively). The prognostic potential of this model was confirmed in the validation cohort. Machine learning showed five prognostic OSRGs (SPHK1, PXDNL, C1QA, WRN, and SETX) to be strongly correlated with platinum resistance in OC patients. Cellular experiments showed that WRN significantly promoted the malignancy and platinum resistance of OC cells.

CONCLUSION

The OSRGs-based risk score model can efficiently predict the prognosis and platinum resistance of OC patients. This model may improve the risk stratification of OC patients in the clinic.

Unraveling the Role of Ubiquitin-Conjugating Enzyme UBE2T in Tumorigenesis: A Comprehensive Review

Ubiquitin-conjugating enzyme E2 T (UBE2T) is a crucial E2 enzyme in the ubiquitin-proteasome system (UPS), playing a significant role in the ubiquitination of proteins and influencing a wide range of cellular processes, including proliferation, differentiation, apoptosis, invasion, and metabolism. Its overexpression has been implicated in various malignancies, such as lung adenocarcinoma, gastric cancer, pancreatic cancer, liver cancer, and ovarian cancer, where it correlates strongly with disease progression. UBE2T facilitates tumorigenesis and malignant behaviors by mediating essential functions such as DNA repair, apoptosis, cell cycle regulation, and the activation of oncogenic signaling pathways. High levels of UBE2T expression are associated with poor survival outcomes, highlighting its potential as a molecular biomarker for cancer prognosis. Increasing evidence suggests that UBE2T acts as an oncogene and could serve as a promising therapeutic target in cancer treatment. This review aims to provide a detailed overview of UBE2T's structure, functions, and molecular mechanisms involved in cancer progression as well as recent developments in UBE2T-targeted inhibitors. Such insights may pave the way for novel strategies in cancer diagnosis and treatment, enhancing our understanding of UBE2T's role in cancer biology and supporting the development of innovative therapeutic approaches.

Salidroside exerts anti-tumor effects in ovarian cancer by inhibiting STAT3/c-Myc pathway-mediated glycolysis

Salidroside (SAL) is a bioactive substance extracted from the traditional Chinese medicine Rhodiola rosea, which exhibits multiple pharmacological effects, such as anti-inflammatory, antioxidant, and anti-tumor properties. Currently, the effects of SAL on the malignant progression of ovarian cancer (OC) and its specific mechanism of action are not clear. Cell Counting Kit 8 (CCK-8), clone formation, Hoechst 33258 staining, flow cytometry, transwell, western blotting and immunofluorescence assays were performed to determine the impacts of SAL on the biological properties of OC cells (CAOV3 and SKOV3) and human normal ovarian epithelial cells (IOSE80). The binding activity of SAL and proteins was evaluated. Glucose consumption, lactate and ATP production, extracellular acidification rate (ECAR) and related proteins were measured to assess glycolysis. Animal models were established to evaluate the impact of SAL treatment in vivo and the expression levels of STAT3/c-Myc pathway-related proteins were determined to explore the relationship between SAL and OC. The results showed that SAL reduced the viability, clone formation, migration and invasion ability of CAOV3 and SKOV3 cells, and induced apoptosis. SAL inhibited epithelial-mesenchymal transition (EMT) and decreased glucose consumption, lactate and ATP production and ECAR. SAL exhibited good binding activity with STAT3 and c-Myc and reduced the expression levels of STAT3/c-Myc pathway and glycolysis-related proteins in vitro and in vivo. In conclusion, SAL exerted anti-tumor effects by interfering with the malignant biological progression of OC cells by inhibiting STAT3/c-Myc pathway-mediated glycolysis.

Beyond tumor‑associated macrophages involved in spheroid formation and dissemination: Novel insights for ovarian cancer therapy (Review)

Ovarian cancer (OC) is the most common and deadly malignant tumor of the female reproductive system. When OC cells detach from the primary tumor and enter the ascitic microenvironment, they are present as individual cells or multicellular spheroids in ascites. These spheroids, composed of cancer and non‑malignant cells, are metastatic units and play a crucial role in the progression of OC. However, little is known about the mechanism of spheroid formation and dissemination. Tumor‑associated macrophages (TAMs) in the center of spheroids are key in spheroid formation and metastasis and provide a potential target for OC therapy. The present review summarizes the key biological features of spheroids, focusing on the role of TAMs in spheroid formation, survival and peritoneal metastasis, and the strategies targeting TAMs to provide new insights in treating OC.

KLF4 promotes cisplatin resistance by activating mTORC1 signaling in ovarian cancer

Ovarian cancer (OC) is a highly fatal gynecological malignancy worldwide, and cisplatin (CDDP) is commonly used as an initial chemotherapy treatment for OC. Nonetheless, most patients ultimately face recurrence because of resistance to cisplatin. Therefore, it is imperative to investigate the underlying mechanisms of drug resistance in OC. By analyzing differential gene expression using TCGA, GDSC, and GEO public databases, we discovered that increased KLF4 expression is strongly linked to chemotherapy resistance and unfavorable outcomes in OC. Subsequent validation through immunohistochemistry and western blotting confirmed the upregulated KLF4 expression in cisplatin-resistance OC cells lines and tissues. To investigate the function of KLF4, functional experiments were performed both in vitro and in vivo. We observed that knocking down KLF4 impaired cisplatin-resistance of OC. Further mechanism research based on RNA-seq and gene enrichment analysis revealed that interfering KLF4 suppressed the activation of mTORC1 pathway. Finally, rescue experiment demonstrated that using mTORC1 pathway inhibitor could attenuate the cisplatin resistance induced by the overexpression of KLF4. In conclusion, our research indicates that KLF4 promotes cisplatin resistance through the activation of mTORC1 signaling, and proposes that inhibiting KLF4 might serve as a viable therapeutic approach to overcoming drug resistance in ovarian cancer.

Effects of curcumin nanoparticles on the proliferation and migration of human ovarian cancer cells assessed through the NF-κB/PRL-3 signaling pathway

Curcumin (CUR) exhibits potential inhibitory effects on tumor growth; however, its hydrophobicity and instability limit its clinical applications. In the present study, we developed CUR nanoparticles (CUR-NPs) and evaluated their biochemical characteristics. Cell uptake and proliferation were assessed using scratch and Transwell assays, respectively. Western blotting was performed to investigate the expression levels of proteins related to the NF-κB/PRL-3 signaling pathway, inflammatory response, cell proliferation, and cell migration in SKOV3 cells. Our findings showed that the blank vector was not cytotoxic to cells, allowing us to disregard any effects caused by the vector itself. CUR-NPs exhibited concentration- and time-dependent inhibitory effects on cell proliferation, surpassing those of CUR alone. Increasing the concentration of CUR-NPs resulted in a reduced cell scratch-healing ability and lower chamber migration capacity. Compared to the control group, expression levels of proteins associated with NF-κB/PRL-3 signaling pathway, inflammatory response (TNF-α and IL-6), cell proliferation (cyclin E1 and cyclin A1), as well as cell migration (N-cadherin and vimentin) were significantly elevated in the lipopolysaccharide (LPS) stimulation and NF-κB p65 overexpression groups. Conversely, E-cadherin expression was significantly decreased under these conditions. However, treatment with high concentrations of CUR-NPs effectively reversed these changes. These results highlight the significant ability of CUR-NPs to inhibit human ovarian cancer cell proliferation and migration, while suppressing inflammatory responses through the regulation of the NF-κB/PRL-3 signaling pathway.

Exosomal miR-4516 derived from ovarian cancer stem cells enhanced cisplatin tolerance in ovarian cancer by inhibiting GAS7

Ovarian cancer (OC) is a devastating disease for women, with chemotherapy resistance taking the lead. Cisplatin has been the first-line therapy for OC for a long time. However, the resistance of OC to cisplatin is an important impediment to its efficacy. Mounting studies showed that ovarian cancer stem cells (OCSCs) affected chemotherapy resistance by secreting exosomes. MicroRNAs (miRNAs) play important roles in exosomes secreted by OCSCs. Here, through the analysis of GEO database (GSE107155) combined with RT-qPCR of OC-related cells/clinical tissues, it was found that hsa-miR-4516 (miR-4516) was significantly up-regulated in OCSCs. Then, OCSCs-derived exosomes were isolated and identified, and it was observed the influence of exosomes on the chemoresistance in SKOV3/cisplatin (SKOV3/DDP) cells. These results manifested that OCSCs-mediated exosomes facilitated the chemoresistance of SKOV3/DDP cells by delivering miR-4516 into them. Growth arrest-specific 7 (GAS7), a downstream target of miR-4516, was determined by bioinformatics prediction combined with molecular biological detection. Next, we up-regulated GAS7 expression and discovered that the promotion of chemoresistance in SKOV3/DDP cells by OCSCs-derived exosomes was significantly impaired. Finally, the mice tumor model of SKOV3/DDP cells was built to estimate the effect of GAS7 over-expression on OC growth. The results showed that GAS7 inhibited the chemoresistance of OC in vivo. In conclusion, our experiments suggested that OCSCs-derived exosomes enhanced OC cisplatin resistance by suppressing GAS7 through the delivery of miR-4516. This study provides a possible target for the treatment of OC DDP resistance.

Folate Receptor Alpha-A Secret Weapon in Ovarian Cancer Treatment?

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy worldwide. Due to its nonspecific symptoms and unreliable screening tools, EOC is not diagnosed at an early stage in most cases. Unfortunately, despite achieving initial remission after debulking surgery and platinum-based chemotherapy, most patients experience the recurrence of the disease. The limited therapy approaches have encouraged scientists to search for new detection and therapeutic strategies. In this review, we discuss the role of folate receptor alpha (FRα) in EOC development and its potential application as a biomarker and molecular target in designing new EOC screening and treatment methods. We summarize the mechanisms of the action of various therapeutic strategies based on FRα, including MABs (monoclonal antibodies), ADCs (antibody-drug conjugates), FDCs (folate-drug conjugates), SMDCs (small molecule-drug conjugates), vaccines, and CAR-T (chimeric antigen receptor T) cells, and present the most significant clinical trials of some FRα-based drugs. Furthermore, we discuss the pros and cons of different FR-based therapies, highlighting mirvetuximab soravtansine (MIRV) as the currently most promising EOC-targeting drug.

Metformin combined with cisplatin reduces anticancer activity via ATM/CHK2-dependent upregulation of Rad51 pathway in ovarian cancer

Ovarian cancer (OC) is the deadliest malignancy of the female reproductive system. The standard first-line therapy for OC involves cytoreductive surgical debulking followed by chemotherapy based on platinum and paclitaxel. Despite these treatments, there remains a high rate of tumor recurrence and resistance to platinum. Recent studies have highlighted the potential anti-tumor properties of metformin (met), a traditional diabetes drug. In our study, we investigated the impact of met on the anticancer activities of cisplatin (cDDP) both in vitro and in vivo. Our findings revealed that combining met with cisplatin significantly reduced apoptosis in OC cells, decreased DNA damage, and induced resistance to cDDP. Furthermore, our mechanistic study indicated that the resistance induced by met is primarily driven by the inhibition of the ATM/CHK2 pathway and the upregulation of the Rad51 protein. Using an ATM inhibitor, KU55933, effectively reversed the cisplatin resistance phenotype. In conclusion, our results suggest that met can antagonize the effects of cDDP in specific types of OC cells, leading to a reduction in the chemotherapeutic efficacy of cDDP.

ALDH and cancer stem cells: Pathways, challenges, and future directions in targeted therapy

Human ALDH comprise 19 subfamilies in which ALDH1A1, ALDH1A3, ALDH3A1, ALDH5A1, ALDH7A1, and ALDH18A1 are implicated in CSC. Studies have shown that ALDH can also be involved in drug resistance and standard chemotherapy regimens are ineffective in treating patients at the stage of disease recurrence. Existing chemotherapeutic drugs eliminate the bulk of tumors but are usually not effective against CSC which express ALDH+ population. Henceforth, targeting ALDH is convincing to treat the patient's post-relapse. Combination therapies that interlink signaling mechanisms seem promising to increase the overall disease-free survival rate. Therefore, targeting ALDH through ALDH inhibitors along with immunotherapies may create a novel platform for translational research. This review aims to fill in the gap between ALDH1 family members in relation to its cell signaling mechanisms, highlighting their potential as molecular targets to sensitize recurrent tumors and bring forward the future development concerning the current progress and draw backs. This review summarizes the role of cancer stem cells and their upregulation by maintaining the tumor microenvironment in which ALDH is specifically highlighted. It discusses the regulation of ALDH family proteins and the crosstalk between ALDH and CSC in relation to cancer metabolism. Furthermore, it establishes the correlation between ALDH involved signaling mechanisms and their specific targeted inhibitors, as well as their functional modularity, bioavailability, and mechanistic role in various cancers.