Search PubMedSearch

SEARCH · Search PubMed

Results for “Platinum resistance”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Molecular targeted therapy in combination with chemotherapy for the treatment of platinum-resistant/refractory ovarian cancer (PROC): a systematic review and network meta-analysis.

BACKGROUND: Although single-agent chemotherapy is the most common approach for treating platinum-resistant or refractory ovarian cancer (PROC), there is growing evidence that combining molecular targeted agents with chemotherapy is beneficial, especially for certain patient groups. However, the most effective combination regimen remains elusive. OBJECTIVES: This Bayesian network meta-analysis (NMA) aims to identify the best combination therapy for PROC. METHODS: Relevant studies were searched in PubMed, EMBASE, Web of Science and the Cochrane Central Register of Controlled Trials from their inception until October 2024. The primary outcomes were overall survival (OS), progression-free survival (PFS) and adverse events (AEs). Statistical analyses were performed using the GEMTC package (1.0-2) and R 4.2.0. This review was registered in PROSPERO (CRD42023428414). RESULTS: Our analysis of 22 randomized controlled trials (RCTs) (n = 3408) demonstrated that chemotherapy combinations with bevacizumab (hazard ratio (HR) = 0.52-0.65), sorafenib (HR = 0.65, 95% confidence interval (CI): 0.45-0.93) or adavosertib (HR = 0.56, 95%CI: 0.35-0.90) significantly improved OS and PFS versus chemotherapy alone. Notably, adavosertib + gemcitabine was associated with an increased risk of grade 3-4 AEs (relative risk (RR) = 1.8, 95%CI: 1.3-2.7), but these were generally manageable. CONCLUSIONS: Bevacizumab-based combinations demonstrate consistent benefits across multiple regimens for PROC. Paclitaxel + bevacizumab emerges as the optimal balance of efficacy and safety. Topotecan + sorafenib could be an alternative for patients who are ineligible for anti-angiogenic therapy.

Humans

[Effect of Cancer Antigen-125 Elimination Rate Constant K and BRCA Mutation Status on the Prognosis of Interval Debulking Surgery in Advanced High-Grade Serous Ovarian Cancer].

OBJECTIVE: To investigate the predictive value of the cancer antigen-125 elimination rate constant K (KELIM) for treatment response and prognosis in patients with advanced high-grade serous ovarian cancer (HGSOC) undergoing neoadjuvant chemotherapy followed by interval debulking surgery (NACT-IDS), and to analyze the combined prognostic significance of KELIM and the mutation status of breast cancer susceptibility gene (BRCA). METHODS: A total of 106 patients with advanced HGSOC who had undergone NACT-IDS were retrospectively enrolled. The KELIM values during neoadjuvant chemotherapy were calculated, and patients were divided into high- and low-KELIM groups using a cutoff value of 1.0. Clinicopathological characteristics, R0 resection rates, and platinum sensitivity rates were compared between the two groups. Logistic regression analysis was performed to identify predictive factors for R0 resection, while Kaplan-Meier survival analysis and Cox proportional hazards regression were performed to evaluate factors associated with progression-free survival (PFS). Furthermore, the patients were stratified according to both KELIM and BRCA status to assess the risk of platinum-resistant recurrence in each subgroup. RESULTS: The R0 resection rate was higher in the KELIM &#x2265; 1 group than in the KELIM < 1 group (77.1% vs 55.2%), and the difference was statistically significant (P = 0.024). Multivariate logistic regression analysis showed that KELIM was an independent predictor of R0 resection (odds ratio [OR] = 2.922, 95% CI: 1.112-7.678). Survival analysis demonstrated longer PFS in the KELIM &#x2265;1 group compared with that in the KELIM <1 group (33.0 months vs 18.0 months), and the difference was statistically significant (P < 0.001). Multivariate Cox regression analysis showed that KELIM &#x2265; 1 was associated with a reduced risk of disease progression (hazard ratio [HR] = 0.481, 95% CI: 0.280-0.826). Combined stratification analysis revealed that no platinum-resistant recurrence was observed in the subgroup with both KELIM &#x2265;1 and a BRCA-positive status (0/21). Compared with patients with KELIM <1 and a BRCA-negative status, this subgroup exhibited a lower risk of platinum-resistant recurrence (OR = 0.053, 95% CI: 0.003-0.932, P = 0.006). CONCLUSION: KELIM is an effective dynamic biomarker for predicting surgical outcomes and PFS in patients undergoing NACT-IDS. Combined stratification by KELIM and BRCA status allows more precise identification of the patient population with both KELIM &#x2265;1 and BRCA-positive status, who have an extremely low risk of platinum-resistant recurrence, thereby providing an important basis for individualized treatment and risk stratification management in patients with advanced HGSOC.

Humans

Beyond the "cold" barrier: Redefining the clinical paradigm of immune checkpoint inhibitor therapy in ovarian cancer.

Ovarian cancer remains an immunologically "cold" tumor, with early all-comer immune checkpoint inhibitor (ICI) trials largely negative despite underlying immunogenicity. This review takes a clinician-centric, stage-specific view linking regimen choice, treatment line, and tumor-immune context to observed outcomes. In the neoadjuvant and first-line settings, unselected ICI combinations with chemotherapy and anti-angiogenic agents failed to improve progression-free survival, whereas adding a poly (ADP-ribose) polymerase (PARP) inhibitor to ICI maintenance yielded modest gains in biomarker-enriched cohorts. In recurrent disease, single-agent ICIs produced objective response rates of 8-15%, and most randomized combinations were negative. The phase III KEYNOTE-B96 trial in platinum-resistant disease demonstrated a progression-free survival benefit in the intention-to-treat population and an overall survival benefit in tumors with programmed death ligand 1 (PD-L1) combined positive score &#x2265;&#x202f;1 when pembrolizumab was paired with weekly paclitaxel with or without bevacizumab, underscoring the value of an immunomodulatory chemotherapy backbone in earlier lines. Ovarian clear cell carcinoma emerges as an immunotherapy-sensitive, chemo-resistant subtype that warrants dedicated stratification. We explain why single-analyte biomarkers-PD-L1, tumor mutational burden, homologous recombination deficiency/BRCA1/2-have not reliably enriched benefit and outline a multidimensional approach integrating genomic scars (e.g., mutational signature 3), immune functional state (Immunoscore, CD8&#x207a; tumor-infiltrating lymphocyte density and CD8&#x207a;: regulatory T-cell ratio), and spatial architecture (inflamed, excluded, desert phenotypes). This framework aims to move beyond the all-comer era toward context-informed precision immunotherapy in ovarian cancer.

Humans

Chalcone-indole hybrid scaffolds as promising anticancer drug candidates: a mini-review.

Cancer treatment is hampered by severe systemic side effects, poor tumor selectivity, and multidrug resistance (MDR). Molecular hybridization integrates chalcone and indole, two privileged antitumor pharmacophores, into one scaffold to generate chalcone-indole hybrids that synergistically enhance antitumor potency, improve tumor targeting, and reverse MDR. This mini-review analyzes literature from 2020 to 2026 on chalcone-indole anticancer hybrids. Based on structural modification patterns, the reported hybrids are categorized into four subgroups: simple substituted, &#x3b1;/&#x3b2;-position modified, N-1 fatty acid-substituted, and multi-pharmacophore fused hybrids. For each category, we summarize structure-activity relationships (SARs), antiproliferative activity, selective toxicity, molecular mechanisms, and in vivo xenograft performance. Most lead compounds exert tumor-suppressive effects via tubulin polymerization inhibition, G2/M cell cycle arrest, ROS overaccumulation, and mitochondrial-dependent apoptosis. Representative hybrids 10a, 12a, 21a, and 25a exhibit remarkable efficacy against drug-resistant colorectal, lung, and breast tumors with favorable in vivo safety. We highlight the application potential of different subtypes for specific malignancies, including &#x3b1;/&#x3b2;-modified analogues for resistant colorectal cancer, N-1 fatty acid-platinum conjugates for platinum-resistant lung cancer, NLRP3 inhibitor 7a for oral cancer, and multi-pharmacophore fused derivatives for broad-spectrum activity. Current bottlenecks limiting clinical transformation are discussed. This review provides structural design rules for developing novel chalcone-indole targeted anticancer agents.

Humans

Epigenetic Repression of TP53 Transcription Underlies Cancer Cell Persistence for Carboplatin Resistance in Non-Small Cell Lung Cancer.

While chemoresistance in non-small cell lung cancer (NSCLC) cells has historically been attributed to permanent genetic mutations, emerging evidence highlights the role of nongenetic transcriptional plasticity and 'drug-tolerant persister' cells. To systematically map these epigenetic vulnerabilities, we utilized a genome-wide CRISPR interference library to screen wild-type TP53 NSCLC (A549) cells under carboplatin selection. Using the DrugZ algorithm and subsequent pathway enrichment analyses, this screen revealed that transcriptional suppression of interstrand crosslink DNA repair networks, including the Fanconi anemia pathway, markedly sensitized cells to carboplatin. Unexpectedly, transcriptional silencing of TP53 and its downstream target CDKN1A emerged as the strongest drivers of resistance, enabling cells to bypass therapy-induced senescence and maintain their proliferative potential later. To validate these findings in a clinically relevant context, we established a chronic carboplatin-resistant cell model (A549CarboR cells). A549CarboR exhibited a reduction in TP53 transcripts, along with decreased H3K27 acetylation and increased DNA hypermethylation on its promoter. Epigenetic remodeling using the DNA methyltransferase inhibitor (DNMTi) was associated with unblocking TP53 transcription, restored p53 signaling, and resensitization of resistant cells to carboplatin. Conversely, histone deacetylase inhibitors induced CDKN1A transcription to bypass TP53, indicating distinct epigenetic circuits. Collectively, the results demonstrate for the first time that TP53 expression is dynamically regulated at the transcriptional level through promoter methylation related to the drug tolerance. These insights emphasize that epigenetic silencing, rather than exclusive genetic loss-of-function, contribute to platinum resistance and underscore the therapeutic potential of pairing platinum regimens with DNMTi to target the transcriptomic plasticity of persistent cancer cell populations.

CRISPR interference screening

The emerging landscape of polymerase &#x3b8; in tumor pathogenesis and precision treatment.

DNA polymerase &#x3b8; (Pol&#x3b8;) has emerged as a central yet paradoxical regulator of genome stability and tumor progression. Unlike conventional DNA repair factors, Pol&#x3b8; governs an error-prone double-strand break repair pathway-termed theta-mediated end joining (TMEJ)-which becomes essential for survival in homologous recombination (HR)-deficient cancers while simultaneously fueling genomic instability. This review presents a comprehensive and updated synthesis of Pol&#x3b8;'s structural architecture, regulatory networks, and context-dependent functions across major malignancies, including ovarian, breast, lung, and colorectal cancers. We highlight recently uncovered mechanisms, such as the iron-FTH1/FTL-POLQ-RAD51 axis in platinum-resistant ovarian cancer, the differential POLQ regulation under methionine restriction in BRCA1-mutant breast cancer, and the identification of germline POLQ mutations defining a novel hereditary colorectal cancer subtype. Beyond DNA repair, we integrate emerging evidence linking Pol&#x3b8; to replication stress tolerance, base excision repair, and immune modulation via type I interferon activation and macrophage polarization. The review also provides a critical evaluation of current Pol&#x3b8; inhibitors-including ART558, RP-6685, novobiocin, and AB25583-focusing on their mechanisms, synthetic lethality profiles, and ability to overcome PARP inhibitor resistance. By bridging molecular mechanisms with tumor biology and therapeutic translation, this review offers a unique framework for understanding Pol&#x3b8; as both a prognostic biomarker and a precision oncology target, with implications for combination therapies involving radiotherapy, immunotherapy, and chemotherapy.

Cancer therapy

pH-Dependent Surface Charge Modulation of Peptide-Coated Poly(lactic-co-glycolic Acid) (PLGA) Nanoparticle for Drug Delivery in Ovarian Cancer.

The development of nanoparticle (NP)-based drug delivery systems that combine passive tumor targeting, physiological stability, and therapeutic efficacy remains a key challenge in cancer nanomedicine. Here, we report a pH-responsive peptide-functionalized poly(lactic-co-glycolic acid) (PLGA) NP system designed for cancer targeting. The PLGA core is coated with a short glutamic acid-lysine-histidine-phenylalanine x3 (EKHFFF) peptide shell, enabling tunable surface charge modulation around its isoelectric point and promoting environmental responsiveness. Physicochemical characterization confirms spherical NPs (~70-75 nm) with good colloidal stability, serum compatibility, and ion-dependent stability in physiological conditions. The peptide coating also provides pH-dependent modulation of the zeta potential. Evaluation of the NPs in ovarian cancer (OvCA) models, including immortalized and patient-derived cell lines (PDCLs), demonstrates efficient uptake across OvCA cell lines, with significantly enhanced internalization in PDCLs compared to immortalized cells. The EKHFFF nanoparticle (EKHFFF NP) induced minimal reactive oxygen species and nitric oxide production in macrophages, indicating low immunogenicity and favorable biocompatibility. Upon platinum loading (EKHFFF-Pt NP), the system exhibits potent cytotoxicity in both platinum-sensitive and platinum-resistant OvCA cell lines, outperforming carboplatin and showing comparable or improved efficacy relative to cisplatin in several cell lines. In vivo studies further demonstrate preferential tumor accumulation, sustained intratumoral retention, and measurable systemic circulation with a half-life of approximately 35 min.

Female

Ovarian Carcinoma Presenting Mucoepidermoid Carcinoma-Like Features in Association With Seromucinous Borderline Tumor: A Real Seromucinous Carcinoma?

Ovarian seromucinous carcinoma is generally classified within the spectrum of endometrioid carcinoma. We report a rare ovarian carcinoma with mucoepidermoid carcinoma-like features arising in direct association with a seromucinous borderline tumor. A 56-year-old postmenopausal female presented with a 10-cm pelvic multilocular cystic tumor and markedly elevated carbohydrate antigen 19-9. Histopathological examination showed a seromucinous borderline tumor with transition to invasive carcinoma composed of mucinous epithelial cells and p40-positive intermediate-like cells. The tumor was diffusely positive for PAX8 and negative for cytokeratin 20, supporting Mullerian differentiation. The p40-positive cell population persisted in the borderline, invasive, and para-aortic lymph node metastatic components. Comprehensive genomic profiling identified KRAS p.G12D without CTNNB1, PTEN, or ARID1A mutations. The patient developed platinum-resistant recurrence and died 11 months after diagnosis. This case is compatible with a potential endometriosis-independent pathway from seromucinous borderline tumor to an aggressive mucoepidermoid-like carcinoma.

mucoepidermoid carcinoma

Lack of cross-resistance between certain platinum coordination compounds in mouse leukemia.

Two congeners of cis-platinum diamminodichloride, 1,2-diamminocyclohexylplatinum malonate (NSC 224964) and 1,2-cyclohexyldiamminoplatinum sulfate (NSC 250427), show approximately equal inhibitory activity in vitro against leukemia L1210 and a line of L1210 (L1210/PDD) that has developed resistance to cis-platinum diamminodichloride. These compounds are also active against L1210/PDD in vivo. These observations suggest that they be tried clinically in patients whose disease has become resistant to cis-platinum diamminodichloride.

Animals

Platinum-induced mutations to 8-azaguanine resistance in Chinese hamster ovary cells.

6 platinum (Pt) compounds were compared in suspension cultured Chinese hamster ovary (CHO-S) cells with respect to their inhibition of growth, their reduction of cloning efficiency, and their induction of mutants resistant to 200 microM (30 micrograms/ml) 8-azaguanine (8-AG) and 3 mM ouabain (OUA), respectively. The toxicity of these compounds can be ranked by the medium concentrations which decrease suspension growth/or cloning efficiency by 50%: cis-Pt(NH3)2-Cl2 (0.9/1.5 microM) greater than Pt(SO4)2 + methylcobalamin (MeB-12) methylation product (20/10 microM) greater than K2PtCl4 (32/50 microM) = K2PtCl6 (34/50 microM) = MePtCl2-3 (60/50 microM) greater than Pt(SO4)2 (66/105 microM). Following 20 h exposures to concentrations which resulted in relative survivals of 80-2%, none of the foregoing compounds increased consistently the frequency of OUA(R) mutants above the spontaneous frequency (6.0 x 10(-6)). Parallel treatments with 800 microM (100 micrograms/ml) ethyl methanesulfonate (EMS) increased the OUA(R) mutant frequency 10--12-fold. Using 8-AG for mutant selection, dose-dependent increases of 5--7-fold above the spontaneous frequency (3--8 x 10(-5) were obtained with cis-Pt(NH3)2Cl2, Pt(S04)2, and the product from Pt(SO4)2 + MeB-12. Identical 20 h exposures to varying amounts of K2PtCl4, K2PtCl6, and MePtCl2-3 did not induce 8-AG(R) mutants. Optimal detection of Pt-induced 8-AG(R) mutants required 7 post-treatments, expression doublings in suspension culture. Under our selection conditions 8/8 spontaneous and 24/24 Pt-induced 8-AG(R) variants contained reduced hypoxanthine-guanine phosphoribosyl transferase (HGPRT) specific activities (means ranging from 3 to 11% of the parental CHO-S cells). When compared from linear plots of the 8-Ag(r) frequency against the initial medium concentration, cis-Pt(NH3)2Cl2 is 134 times and Pt(SO4)2 si 3.5 times more mutagenic than EMS. However, on a cell-survival basis EMS is 8--10-fold more mutagenic than these two Pt-compounds. 6-Thioguanine (10 microM) can be substituted for 8-AG to assay mutant induction by cis-Pt(NH3)2Cl2 and Pt(SO4)2 in CHO-S cells. The sensitivity of the CHO-S HGPRT locus for detecting mutagenesis by Pt complexes can be increased several fold by continuous subculture in the presence of these agents for 10--25 population doublings. By this procedure K2PtCl6 is seen to be weakly mutagenic and 20 microM Pt(SO4)2 produces 8-AG(R) mutants at frequencies requiring 7--8-fold higher concentrations when a fixed 20 h exposure is used.

Animals

DHX9 Inhibition Enhances Paclitaxel Sensitivity by Inducing Mitotic Failure in Ovarian and Endometrial Cancers.

Recurrent high-grade serous ovarian carcinoma (HGSOC) and endometrial cancer remain major clinical challenges with limited effective treatment options. DExH-box helicase 9 (DHX9), a DNA/RNA helicase essential for genomic stability, has not yet been explored as a therapeutic target in gynecologic cancers. In this study, we show that a selective DHX9 inhibitor (DHX9i) suppresses proliferation in a subset of HGSOC and endometrial cancer cell lines by inducing DNA damage, chromosomal instability, and mitotic failure. This effect was independent of microsatellite instability status and prior resistance to platinum or PARP inhibitors. Genomic analysis indicated that DHX9i resistance was unlikely to be driven by single-gene mutations but was instead associated with copy-number alterations in mitotic spindle and microtubule-regulating genes in both HGSOC and endometrial cancer. Transcriptomic profiling further revealed consistent alterations in microtubule- and spindle-associated pathways in DHX9i-resistant models following DHX9i treatment. Mechanistically, DHX9i induced mitotic defects in DHX9i-sensitive models, whereas resistant lines maintained mitotic integrity. Given the convergence of resistance-associated features on microtubule-related pathways, we combined DHX9i with the microtubule-stabilizing agent paclitaxel to enhance mitotic stress. This combination triggered mitotic disruption and enhanced cytotoxicity in DHX9i-resistant cells. In vivo, the combination led to sustained tumor regression and prolonged survival in both DHX9i-sensitive and DHX9i-resistant models without notable toxicity. Overall, our findings define genomic, transcriptomic, and phenotypic characteristics associated with differential responses to DHX9i and support the clinical evaluation of the DHX9i-paclitaxel combination as a therapeutic strategy in recurrent gynecologic cancers.

Female

Whole-Exome Sequencing Identifies Candidate Genomic Features Associated with Response to Platinum-Based Chemotherapy and Ixabepilone-Based Treatment in Ovarian Cancer.

Carboplatin/paclitaxel (CP) chemotherapy is the cornerstone of therapy for advanced stage ovarian cancer (OC). However, despite initial sensitivity, this regimen cannot avoid the emergence of resistance. Ixabepilone &#xb1; bevacizumab (IB) is a combination recently added to NCCN guidelines for the treatment of platinum-resistant OC. It would be desirable to identify biomarkers able to differentiate patients who are resistant to CP and IB, and biomarkers that identify which patients may benefit from IB treatment. We analyzed whole-exome-sequencing (WES) data from 49 OC patients exposed to CP, including 28 platinum-sensitive vs. 21 platinum-resistant, and 31 additional platinum-resistant patients, including 16 responders (i.e., CR/PR) vs. 15 non-responders (SD/PD) to ixabepilone &#xb1; bevacizumab. Comprehensive genetic analyses were performed to identify alterations correlated with resistance to CP and IB. WES analysis of CP responders vs. non-responders revealed differences in HRD-signatures (p < 0.05), OS (p < 0.005) and gain/loss-of-function in multiple genes associated with tumor growth/progression including but not limited to ACVR2A, INHBA, MAP3K7, ATG5, SGK1, FYN, RSPO3, NOD1 and LRRK2. WES analysis of platinum-resistant IB-treated patients revealed additional nominally significant genes and deranged pathways including gains in the DROSHA and SDHA genes in responders vs. non-responders (p < 0.05). Patients harboring HRD-signatures showed significantly higher sensitivity to CP and prolonged survival compared to HRD-negative patients. Alterations in genes associated with tumor growth/progression correlated with resistance to CP regimen and may represent novel "druggable" candidate biomarkers for the targeted treatment of CP/IB-resistant patients. Further validation in independent cohorts and preclinical experiments in CP/IB-resistant models are warranted to establish the clinical utility of these findings.

Humans

Heme oxygenase 1 (HO-1) is a drug target for reversing cisplatin resistance in non-small cell lung cancer.

INTRODUCTION: Platinum-based drugs, the most widely used chemotherapeutic drugs in clinical oncology, have long faced the problem of drug resistance, which is urgently in need of resolution. Identifying biomarkers of drug resistance may help reduce platinum resistance and improve therapeutic efficacy. OBJECTIVES: This study aims to identify potential biomarkers associated with the development of cisplatin resistance in non-small cell lung cancer (NSCLC) and explore mechanisms to overcome chemoresistance. METHODS: NSCLC cisplatin resistance cell lines were constructed, and transcriptome sequencing was performed. Results were validated using Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Molecular docking, proteomics sequencing, and in vitro and in vivo experiments were conducted to evaluate the role of Heme Oxygenase 1 (HO-1) in cisplatin resistance. RESULTS: NSCLC cisplatin resistance cell lines, GEO and TCGA data identified HMOX1, downstream of Nrf2, as a key drug resistance gene induced by cisplatin. Activation of the Nrf2/HO-1 pathway was found to induce ferroptosis resistance, a critical mechanism of cisplatin resistance. Candidate compounds SB 202190 and Nordihydroguaiaretic acid (NDGA) effectively reactivated ferroptosis by inhibiting HO-1, thereby increasing cisplatin sensitivity. CONCLUSION: The Nrf2/HO-1 pathway is a significant contributor to cisplatin resistance in NSCLC. Targeting HO-1 with SB 202190 and NDGA presents a promising strategy to overcome resistance and improve chemotherapy outcomes.

Cisplatin

Multidimensional Proteomics Reveals the Pro-apoptotic Mechanism of Platycodin D: Targeting RFC4 to Regulate the Notch Signaling Axis in Non-Small Cell Lung Cancer.

Platycodin D (PD), a major bioactive saponin isolated from the traditional Chinese medicine Platycodon grandiflorus, has shown promising therapeutic potential against non-small cell lung cancer (NSCLC). However, the functional mechanisms of PD in NSCLC progression remains unclear. This study aimed to explore the pharmacological mechanism of PD against NSCLC. Thermal proteome profiling approach, molecular docking, cellular thermal shift assay and peptide-centric local stability assay were employed to identify the potential binding target of PD. Subsequent Western Blot and immunoprecipitation-Western Blot experiments were conducted to investigate the downstream signaling pathways of the target. Furthermore, proteomic and ubiquitinomic profiling of PD-treated cells were performed to investigate its functions on global. replication factor C subunit 4 (RFC4) was identified as a potential binding target of PD by thermal proteome profiling and their binding sites were further exposed by peptide-centric local stability assay. PD-RFC4 complex promotes the degradation of Notch1 and Notch3 by reducing nuclear entry of their domains. Compared with control treatment, the differentially expressed proteins induced by PD were found to be primarily involved in ferroptosis, ubiquitination, platinum drug resistance, and ribosome-related processes. The ubiquitin proteome analysis revealed that proteins associated with the Notch pathway underwent ubiquitin modifications. PD binds to RFC4 and inhibits its activity, leading to downregulation of the Notch signaling pathway, ultimately triggering cancer cell apoptosis. PD is a natural product with potential therapeutic value for NSCLC.

Saponins

Cross-resistance of Escherichia coli B/r to cis-platinum (II) diamminochloride, UV light and alkylating agents.

Gradual transfers of the strain Escherichia coli B/r on M9 agar with increasing concentrations of cis-platinum (II) diamminochloride (cis-Pt(II)) yielded a resistant strain SM 405 capable of growing on liquid M9 medium containing 250 muM cis-Pt(II). The parent strain Escherichia coli B/r is completely inhibited in both division and growth at cis-Pt(II) concentrations as low as 30 muM. The resistant mutant has a longer doubling time than the parent strain. No other differences were found between the two strains. To elucidate the nature of the resistance, the effect of cis-Pt(II) on the survival of the two strains was compared with that of nitrogen mustard, UV light and ethyl methanesulphonate (EMS). The resistant strain SM 405 was found to be more hardened against the lethal action of UV light and nitrogen mustard but less so against EMS. It had also a higher ability of a host-cell reactivation of UV-irradiated phage T3. The different resistance of the B/r and SM 405 strains is probably due to a mutation increasing the effectiveness of the excision repair in the latter.

Cisplatin

[Combination of adriamycin and cis-diammine-dichloro-platinum (II) in the treatment of advanced, therapy-resistant, ovarian carcinoma (author's transl)].

Adriamycin (doxorubicin, Adriblastin) and cis-diammine-dichloro-platinum (II) (DDP, NSC 119 875) were used in the treatment of 18 patients with ovarian carcinoma, usually after intensive pre-treatment, both in a dosage of 50 mg/m2 once every 4 weeks. Forced diuresis was initiated at the same time. On average three such treatments were given. Six patients showed partial remission defined as decrease of tumour mass by more than 50% or as almost complete disappearance of ascites during more than two months without concomitant diuretic treatment. The remission time was 2+, 3, 3+, 3.5, 7+, and 9+ months. In all patients severe gastrointestinal toxicity occurred, however the myelosuppressive action was only moderate. Nephrotoxicity was negligible. Combined chemotherapy with Adriblastin and DDP thus seems effective even in intensively pretreated patients with ovarian carcinoma.

Adult

Synergistic effects of the combination of cis-platinum diamminodichloride and 2,2'-anhydro-1-beta-D-arabinofuranosyl-5-fluorocytosine in transplanted mouse leukemias.

cis-Platinum diamminodichloride has been studied in combination with 2,2'-anhydro-1-beta-D-arabinofuranosyl-5-fluorocytosine on an every-4-day schedule in various lines of mouse leukemia. This combination is synergistic in leukemias L1210 and P388 and sublines made resistant to 5-fluorouracil or methotrexate. There is no cross-resistance between cis-platinum diamminodichloride and 2,2'-anhydro-1-beta-D-arabinofuranosyl-5-fluorocytosine, but the combination is no more effective against lines of leukemia made resistant to cis-platinum diamminodichloride or to 2,2'-anhydro-1-beta-D-arabinofuranosyl-5-fluorocytosine than either single active compound alone. Since these compounds have no cross-resistance, act by quite different mechanisms of action, and have different limiting toxicity, the combination is now being evaluated clinically.

Ancitabine

Predictive modeling of gene mutations for the survival outcomes of epithelial ovarian cancer patients.

Epithelial ovarian cancer (EOC) has a low overall survival rate, largely due to frequent recurrence and acquiring resistance to platinum-based chemotherapy. EOC with homologous recombination (HR) deficiency has increased sensitivity to platinum-based chemotherapy because platinum-induced DNA damage cannot be repaired. Mutations in genes involved in the HR pathway are thought to be strongly correlated with favorable response to treatment. Patients with these mutations have better prognosis and an improved survival rate. On the other hand, mutations in non-HR genes in EOC are associated with increased chemoresistance and poorer prognosis. For this reason, accurate predictions in response to treatment and overall survival remain challenging. Thus, analyses of 360 EOC cases on NCI's The Cancer Genome Atlas (TCGA) program were conducted to identify novel gene mutation signatures that were strongly correlated with overall survival. We found that a considerable portion of EOC cases exhibited multiple and overlapping mutations in a panel of 31 genes. Using logistical regression modeling on mutational profiles and patient survival data from TCGA, we determined whether specific sets of deleterious gene mutations in EOC patients had impacts on patient survival. Our results showed that six genes that were strongly correlated with an increased survival time are BRCA1, NBN, BRIP1, RAD50, PTEN, and PMS2. In addition, our analysis shows that six genes that were strongly correlated with a decreased survival time are FANCE, FOXM1, KRAS, FANCD2, TTN, and CSMD3. Furthermore, Kaplan-Meier survival analysis of 360 patients stratified by these positive and negative gene mutation signatures corroborated that our regression model outperformed the conventional HR genes-based classification and prediction of survival outcomes. Collectively, our findings suggest that EOC exhibits unique mutation signatures beyond HR gene mutations. Our approach can identify a novel panel of gene mutations that helps improve the prediction of treatment outcomes and overall survival for EOC patients.

Humans