LA-D-B1,a novel Abemaciclib derivative,exerts anti-breast cancer effects through CDK4/6

Background:Regulatory proteins involved in human cellular division and proliferation,cyclin-dependent kinases 4 and 6(CDK4/6)are overexpressed in numerous cancers,including triple-negative breast cancer(TNBC).TNBC is a common pathological subtype of breast cancer that is prone to recurrence and metastasis,and has a single treatment method.As one of the CDK4/6 inhibitors,abemaciclib can effectively inhibit the growth of breast tumors.In this study,we synthesized LA-D-B1,a derivative of Abemaciclib,and investigated its anti-tumor effects in breast cancer.Methods:Cellular viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.Cell cloning and migration abilities were determined by colony formation assay and wound healing assay.Cell invasion abilities and adhesion were determined by cell invasion assay and cell adhesion assay.The impact of compound LA-D-B1 on cell proliferation and the cell cycle was analyzed through Western blotting,which quantified the levels of proteins associated with the cyclin-dependent kinase(CDK)4/6-cyclin D-Rb-E2F pathway.The in vivo anti-tumor activity of compound LA-D-B1 was investigated using a chick chorioallantoic membrane(CAM)model.Results:The study demonstrated that LA-D-B1 effectively suppressed breast cancer cell proliferation,induced apoptosis,and caused cell cycle arrest.Furthermore,LA-D-B1 reduced the expression of key proteins in the CDK4/6-cyclin D-Rb-E2F pathway,including CDK4,CDK6 and E2F1.The results also indicated significant antitumor activity of LA-D-B1 in a transplanted tumor model.Conclusion:In this study,LA-D-B1 demonstrated a potent anti-tumor effect by effectively suppressing cell proliferation and inhibiting cell cycle progression in breast cancer.These findings highlight the potential of LA-D-B1 as a valuable compound for enhancing therapeutic outcomes and controlling the progression of breast cancer.

Case Report of Denovo Musculoskeletal Metastasis from Hormonal Positive and Her2 Negative Receiving CDK4 Inhibitor

Skeletal muscle metastasis from breast cancer is a very rare presentation. We reported a case with breast cancer metastatic to skeletal muscle, bone, peritoneum and lymph node at presentation detected in FDG PET-CT. A Core needle biopsy was performed from the left breast tail lesion. Immunohistochemistry showed hormonal positivity, Her2 negativity with low KI67. Patient was treated with combined CDK4 inhibitor and non-steroidal aromatase inhibitors with regressive course in the PET-CT after the 1st 3 months. More studies should investigate the prognosis and proper management of skeletal muscle metastasis in breast cancer.

CDK4/6抑制剂所致药物不良反应文献分析及思考

目的分析CDK4/6抑制剂在临床应用中所致不良反应(ADR)的特点,为临床安全用药提供参考。方法检索维普、中国知网、万方、Web of Science、PubMed等数据库中关于CDK4/6抑制剂致ADRs的文献并进行分析。结果CDK4/6抑制剂致ADRs的个案报道共34例;患者平均年龄约63.5岁,ADRs多发生在用药4个月内(29例,85.29%);CDK4/6抑制剂致ADRs主要以皮肤及其附件损害(14例,41.18%)、呼吸系统损害(6例,17.65%)、肝胆系统损害(4例,11.76%)为主;经停药和/或对症治疗后达到症状好转或治愈的有31例;3例最终死亡。结论临床使用CDK4/6抑制剂时应加强用药监测,开展多学科患者管理,而CDK4/6抑制剂的ADR发生机制尚需进一步研究。

CDK4/6 inhibitors in the treatment of hormone receptor-positive, HER2-negative advanced breast cancer

Endocrine therapy(ET)is the therapy backbone of hormone receptor(HR)-positive and human epidermal growth factor receptor 2(HER2)-negati ve advanced breast cancer.However,there are about 20%HR positive patients with no response to ET due to primary or acquired ET resistance.In this background,many agents have been studied to overcome ET resistance and of which the important agents are cyclin-dependent kinase 4/6(CDK4/6)inhibitors.The prognosis of advanced breast cancer has been improved by combing ET with CDK4/6 inhibitors.In this review,we mainly focused on the CDK4/6 inhibitors in the treatment of HR-positive,HER2-negative advanced breast cancer and discussed the action mechanisms of CDK4/6 inhibitors alone or combined with ET.We also summarized several molecular features that would predict response or resistance to CDK4/6 inhibitors.In addition,we put forward possible strategies to overcome CDK4/6 inhibitor resistance according to the latest research.

Impact of Drug-Drug Interaction between CDK4/6 Inhibitors and Proton Pump Inhibitors on Survival Outcomes in the Treatment of Metastatic Breast Cancer—Real World Data from a Portuguese Center

Introduction: Proton pump inhibitors (PPi) are widely prescribed, including in patients undergoing treatment for advanced breast cancer (ABC). Due to the pharmacokinetic characteristics of the CDK4/6 inhibitor (Ci) palbociclib a drug interaction with PPi was hypothesized. It was shown in a retrospective study that this association was an independent predictive factor for worse progression-free survival (PFS). Objective: To verify the impact of concomitant administration of PPi with Ci on overall survival (OS) and PFS. Material and Methods: This is a retrospective cohort study of patients treated with Ci for HR+HER2-ABC in the period from Feb/2017 to Aug/2020. SPSS software was used for data processing. Univariate analysis was done by the Kaplan-Meier method and log-rank test, and multivariate analysis by COX regression. P-value < 0.05 was considered significant. Results: 80 patients were included. The median age at diagnosis of ABC was 56 years (25 - 75). Treatment with Ci was 1st line for ABC in 68.8%. Choice of Ci was palbociclib in 73.8% (n = 59) and ribociclib in 26.3% (n = 21). The hormone partner was a nonsteroidal aromatase inhibitor in 45.0%, and fulvestrant in 55.0% of cases. 37.5% of patients were on PPi, and 70.0% of them were during the entire treatment (23.3% omeprazole, 73.4% pantoprazole, 3.3% others). Patients taking concomitant PPi and Ci had lower OS (OS-3 years 42.6% vs. 63.4%, p = 0.254) and PFS (PFS med 15 m. vs. 21 m., p = 0.733), although with no statistically significant difference. Discussion: In the sample, there was a numerical difference, without the statistical significance in the use of PPi in the survival of patients under Ci. This difference could be more evident with a longer follow-up and a larger sample size. This study intends to alert to the growing importance of checking for drug interactions. Polymedication, advanced age and the presence of several comorbidities are real problems in patients with ABC. Conclusion: Real-world data from this center demonstrate a negative, non-statistically significant impact of PPi treatment on survival outcomes, in patients treated with Ci for HR+HER2-ABC.

Pharmacophore Based Virtual Screening for Identification of Novel CDK₂Inhibitors

CDK2 is one of the most important members of Cyclin-dependent kinases. It is a critical modulator of various oncogenic signaling pathways, and its activity is vital for loss of proliferative control during oncogenesis. This work has focused on developing a pharmacophore model for CDK2 inhibitors by using a dataset of known inhibitors as a pre-filter throughout the virtual screening and docking process. Consequently, the best pharmacophore model was made of one hydrogen bond acceptor, and two aromatic ring features with a high correlation value of 0.906. The validation findings proved out that the selected model can be used as a filter to screen new molecules like Enamine kinase hinge region directed library against CDK2. As a result, 69 hits were subjected to molecular docking studies. Eventually, three compounds (5909, 701 and 8397) scored good interaction energy values and strong molecular interactions. Hence, they were identified as leads for novel CDK2 inhibitors as anticancer drugs.

A Systematic Review of Economic Evaluation of CDK4/6 Inhibitors in HR+/HER2-Advanced Breast Cancer

Objective To review the domestic and foreign economic studies on CDK4/6 inhibitors in first-line or second-line treatment of HR+/HER2-advanced breast cancer,and to analyze the main methodologies and research results.Methods Systematic literature review was used to search PubMed,EMBASE,Cochrane Library,CNKI,CBM,and Wanfang database.The incremental cost-effectiveness ratio was taken as the main outcome index,and all pharmacoeconomic evaluations with CDK4/6 inhibitors as intervention measures were included,such as Palbociclib,Ribociclib,and Abemaciclib.According to the Quality of Health Economic Studies Instrument,the quality of the included articles was evaluated,and then the included literature was analyzed.Results and Conclusion A total of 16 pharmacoeconomic evaluation studies were included,mainly from the perspective of national healthcare systems or third-party payers.Only 2 studies focused on second-line treatment,and the remaining treatment levels were first-line treatment.In terms of model structure,7 studies adopted the Markov model,6 studies adopted the PSM model,and 3 studies adopted the DES model.The basic analysis results showed that CDK4/6 inhibitor combined with endocrine regimen was not economical compared with endocrine alone regimen when the threshold was the conventional willingness to pay(WTP)value of each country.The uncertainty analysis included deterministic sensitivity analysis and probability sensitivity analysis.The included studies are all Cost-Utility Analysis with high-quality evaluation,which can provide evidence support for health-related decision-makers in decision-making.It can also provide methodological reference for the economic evaluation of other targeted drugs.

Cyclins/CDKs及其抑制剂的抗瘤作用

本文简要介绍了细胞周期蛋白 (Cyclins)、周期蛋白依赖性激酶 (Cyclin DependentKinases,CDKs)以及周期蛋白依赖性激酶抑制因子 (Cyclin DependentKinasesInhibitors ,CKIs)的研究最新进展以及周期调控中关键蛋白及相关抑制因子之间的相互关系 ,并着重介绍了内、外源抑制剂对细胞周期的调节作用及它们的抗瘤作用。

CDK抑制剂的研究进展

周期蛋白依赖性激酶是一类丝/苏氨酸激酶,是一种细胞内重要的信号转导分子。目前以细胞周期蛋白依赖性激酶为靶点的药物可以阻断细胞的周期,控制细胞的增殖,从而达到抗肿瘤的目的。文章简单的对几种与肿瘤相关的CDK抑制剂进行综述,对新的CDK抑制剂研发提供背景分析。

细胞周期依赖性蛋白激酶(CDK)抑制剂Xylocydine合成研究进展

介绍了细胞周期依赖性蛋白激酶(CDK)抑制剂Xylocydine的发现及其生物活性,并综述了Xylocydine合成路线的研究进展。

CDK抑制剂2-(6-(苄基氨基)-9-环丙甲基-9H-嘌呤-2-氨基)-1-丁醇的合成及抗肿瘤活性研究

以2,6-二氯嘌呤为起始原料,依次通过与苄胺、环丙甲基溴和2-氨基-1-丁醇等发生缩合经三步反应合成了一种CDK抑制剂类似物.产品及中间体的结构经ESI-MS和1 H NMR确证,该方法操作步骤简便、条件温和、收率较高,适合制备具有类似结构的嘌呤衍生物,具有一定的通用性.初步活性测定结果显示其具有抗肿瘤活性.

Focus on current and emerging treatment options for glioma:A comprehensive review

This comprehensive review delves into the current updates and challenges associated with the management of low-grade gliomas(LGG),the predominant primary tumors in the central nervous system.With a general incidence rate of 5.81 per 100000,gliomas pose a significant global concern,necessitating advancements in treatment techniques to reduce mortality and morbidity.This review places a particular focus on immunotherapies,discussing promising agents such as Zotiraciclib and Lerapolturev.Zotiraciclib,a CDK9 inhibitor,has demonstrated efficacy in glioblastoma treatment in preclinical and clinical studies,showing its potential as a therapeutic breakthrough.Lerapolturev,a viral immunotherapy,induces inflammation in glioblastoma and displays positive outcomes in both adult and pediatric patients.Exploration of immunotherapy extends to Pembrolizumab,Nivolumab,and Entrectinib,revealing the challenges and variabilities in patient responses.Despite promising preclinical data,the monoclonal antibody Depatuxizumab has proven ineffective in glioblastoma treatment,emphasizing the critical need to understand resistance mechanisms.The review also covers the success of radiation therapy in pediatric LGG,with evolving techniques,such as proton therapy,showing potential improvements in patient quality of life.Surgical treatment is discussed in the context of achieving a balance between preserving the patient’s quality of life and attaining gross total resection,with the extent of surgical resection significantly influencing the survival outcomes.In addition to advancements in cancer vaccine development,this review highlights the evolving landscape of LGG treatment,emphasizing a shift toward personalized and targeted therapies.Ongoing research is essential for refining strategies and enhancing outcomes in the management of LGG.

Beyond clinical trials:CDK4/6 inhibitor efficacy predictors and nomogram model from real‐world evidence in metastatic breast cancer

Background:CDK4/6 inhibitors(CDK4/6i)have shown promising results in the treatment of hormone receptor‐positive(HR+)metastatic breast cancer(MBC)when combined with endocrine therapy(ET).It is crucial to evaluate the actual effectiveness and safety of CDK4/6i in clinical practice,as well as to analyze the factors that can predict their outcomes.Methods:Patients with HR+MBC who received CDK4/6i‐based therapy between May 2016 and May 2023 at Hunan Cancer Hospital were evaluated for progression‐free survival(PFS).Adverse reactions were assessed based on the National Cancer Institute Common Toxicity Criteria(version 5.0).Results:This study included 344 patients,with a median PFS(mPFS)of 12.8 months(range:10.4–15.2 months).After adjustment,Cox multivariate regression analysis revealed that visceral metastasis(specifically liver and brain metastases),Eastern Cooperative Oncology Group Performance Status(ECOG PS)≥1,estrogen receptor≤80%,progesterone receptor≤10%,Ki‐67>30%,and treatment in later stages were significant factors associated with reduced PFS.Based on this,we created a prognostic nomogram and validated its performance,obtaining a C‐index of 0.714(95%confidence interval:0.640–0.787)as well as reliable calibration and clinical impact.The mPFS of CDK4/6i rechallenge was 7.7 months;for patients who initially discontinued CDK4/6i for reasons other than disease progression,CDK4/6i rechallenge still provided a mPFS of 11.4 months.The tolerability and safety of combining CDK4/6is with ET were manageable.Adverse events led to treatment discontinuation in 3.8%of patients.Neutropenia(29.1%),leukopenia(13.7%),and anemia(4.1%)were the primary grade 3/4 adverse reactions.Conclusions:This real‐world study highlights the ample efficacy and reasonable safety of combined CDK4/6i and ET in patients with HR+MBC.Individualized treatment decisions and ongoing safety monitoring are important to optimize the therapeutic benefit of CDK4/6i treatment.

Circadian variation in expression of G_1 phase cyclins D_1 and E and cyclin-dependent kinase inhibitors p16 and p21 in human bowel mucosa

AIM： To evaluate whether the cellular proliferation rate in the large bowel epithelial cells is characterized by circadian rhythm. METHODS： Between January 2003 and December 2004, twenty patients who were diagnosed as suffering from primary, resectable, non-metastatic adenocarcinoma of the lower rectum, infiltrating the sphincter mechanism, underwent abdominoperineal resection, total mesorectal excision and permanent left iliac colostomy. In formalinfixed and paraffin-embedded biopsy specimens obtained from the colostomy mucosa every six hours （00：00, 06：00, 12：00, 18：00 and 24：00）, we studied the expression of G1 phase cyclins （D1 and E） as well as the expression of the G1 phase cyclin-dependent kinase （CDK） inhibitors p16 and p21 as indicators of cell cycle progres- sion in colonic epithelial cells using immunohistochemical methods. RESULTS： The expression of both cyclins showed a similar circadian fashion obtaining their lowest and highest values at 00：00 and 18：00, respectively （P〈 0.001）. A circadian rhythm in the expression of CDK inhibitor proteins p16 and p21 was also observed, with the lowest levels obtained at 12：00 and 18：00 （P〈0.001）, respectively. When the complexes cyclins D1-p21 and E-p21 were examined, the expression of the cyclins was adversely correlated to the p21 expression throughout the day. When the complexes the cyclins D1-p16 and E-p16 were examined, high levels of p16 expression were correlated to low levels of cyclin expression at 00：00, 06：00 and 24：00. Meanwhile, the highest expression levels of both cyclins were correlated to high levels of p16 expression at 18：00. CONCLUSION： Colonic epithelial cells seem to enter the G1 phase of the cell cycle during afternoon （between 12：00 and 18：00） with the highest rates obtained at 18：00. From a clinical point of view, the present results suggest that G1-phase specific anticancer therapies in afternoon might maximize their anti-tumor effect while minimizing toxicity.

CDK抑制剂SNS-032联合AD55-Apoptin对肝癌细胞Huh-7的体外抗癌作用

通过CDK抑制剂SNS-032联合AD55-Apoptin处理肝癌Huh-7细胞,以探究两者联合作用的体外抗癌作用。采用MTT法分别检测SNS-032、AD55-Apoptin以及SNS-032与AD55-Apoptin联合对肝癌细胞株Huh-7生长的抑制作用;利用Hoechst33342染色观察所处理细胞的凋亡形态学变化,采用流式细胞术对凋亡进行量化,Western Blot检测凋亡相关蛋白表达情况。结果表明：10MOI的AD55-Apoptin联合100ng/mL的SNS-032处理96h后,Huh-7细胞的存活率仅为4%,而10 MOI的AD55-Apoptin和100ng/mL SNS-032分别单独处理后细胞存活率为60%和8%（P〈0.05）;Hoechst33342染色、流式检测及Western Blot结果表明,联合处理组细胞凋亡现象更明显。实验结果证明SNS-032联合AD55-Apoptin能有效的抑制肝癌细胞Huh-7生长,并诱导其凋亡。

Synergistic Anticancer Activity of Topotecan— Cyclin-Dependent Kinase Inhibitor Combinations against Drug-Resistant Small Cell Lung Cancer (SCLC) Cell Lines

Extended-stage small cell lung cancer (SCLC) responds to platinum/vepeside-based first-line chemotherapy but relapses rapidly as drug-resistant tumor. Topotecan (TPT) is the single chemotherapeutic agent approved for second-line treatment of SCLC. However, the response to TPT is short-lived and novel treatment modalities need to be developed. Sequential treatment of cytotoxic drugs and inhibitors of cyclin-dependent kinases (CDKs) showed promising preclinical anticancer activity and, in the present work, combinations of TPT with CDK inhibitors olomoucine, roscovitine and CDK4I are shown to exhibit synergistic cytotoxic activity against SCLC cell lines. Highest activity was found against TPT-resistant NCI-H417 and DMS153 cell lines and moderate chemosensitizing effects against a primary SCLC cell line and sensitive GLC19 cells at levels of CDK inhibitors which exerted low toxicity. A combination of 0.6 μM TPT with 0.6 μM roscovitine, exhibiting no significant cytotoxicity as single agents, reduced viability of the TPT-resistant NCI-H417 line (IC50 > 10 μM) by 50%. In the TPT resistant cell lines olomoucine and roscovitine, targeting CDK1,2,5,7, were highly effective, whereas in the more sensitive cell lines CDK4I, inhibiting mainly CDK4/6, showed activity. In NCI-417 cells, preincubation with roscovitine for one day proved synergistic with TPT. Thus, in good accordance with previous findings, CDK inhibitors are able to convert SCLC cancer cells which are cell-cycle arrested by a blockade of topoisomerase I by TPT to apoptotic cells. Since nowadays several CDK inhibitors are at various phases of clinical testing their combination with TPT seems to constitute a promising approach to improve second-line chemotherapy in SCLC.

FLT3及CDK抑制剂在白血病治疗领域的研究进展

白血病是一系列始发于骨髓,最终导致机体造血功能异常并分化大量未成熟白细胞的癌症的总称。常见的类型有急性髓细胞样白血病(AML)、慢性淋巴细胞白血病(CLL)等。其疾病机理复杂,与许多生理信号转导通路都有关联。这提示了我们针对相关信号转导通路的小分子抑制剂可以治疗白血病。本文就其中代表性的FLT3及CDK抑制剂在白血病治疗中的应用进行了阐述。

Clinical benefit and safety profile of cross-line therapy with CDK4/6 inhibitors:a retrospective study of HR+/HER2–advanced breast cancer

Objective:CDK4/6 inhibitors(CDK4/6is)in combination with endocrine therapy have secured a central role in the treatment of hormone receptor(HR)-positive advanced breast cancer(ABC)and have transformed the therapeutic landscape.Cross-line CDK4/6i therapy in which another CDK4/6i is continued after progression on a prior CDK4/6i may still offer advantageous therapeutic effects.Cross-line CDK4/6i therapy is an area of active investigation in the ongoing pursuit to improve outcomes for patients with HR+/human epidermal growth factor receptor 2(HER2)–ABC.Methods:This retrospective study enrolled 82 patients with HR+/HER2–ABC who were treated with cross-line CDK4/6is(abemaciclib,palbociclib,ribociclib,and dalpiciclib)after progression with another CDK4/6i.The primary endpoint was progression-free survival(PFS)according to version 1.1 of the Response Evaluation Criteria in Solid Tumors.Secondary endpoints included toxicity,objective response rate,disease control rate,and overall survival.Adverse events(AEs)were graded according to version 5.0 of the Common Terminology Criteria for Adverse Events,as promulgated by the U.S.Department of Health and Human Services.Results:Eighty-two HR+/HER2–ABC patients who received cross-line CDK4/6i therapy from January 2022 to February 2024 were enrolled.The median age of the patients was 60 years.The median PFS of all patients was 7.6 months(95%CI,5.9-9.2).Cox regression analysis identified lung metastasis and a switch to endocrine therapy following prior CDK4/6i therapy as independent predictive factors for PFS.Notably,patients who previously received abemaciclib and switched to palbociclib upon disease progression had a median PFS of 10.7 months.The strategy of transitioning to chemotherapy after progression on a prior CDK4/6i,then to a subsequent CDK4/6i merits further investigation.Hematologic toxicity was the most common grade≥3 AEs.No instances of fatal safety events were observed.Conclusions:Cross-line CDK4/6i therapy is associated with significant clinical benefits and manageable safety profiles in patients with HR+/HER2–ABC,which underscores cross-line CDK4/6i therapy potential as an effective treatment strategy.

CDK12抑制剂在卵巢癌治疗中的研究进展

卵巢癌是死亡率最高的妇科肿瘤,其主要亚型高级浆液性卵巢癌的标准治疗模式效果欠佳,目前尚缺乏有效的临床治疗手段。细胞周期蛋白依赖性激酶(cyclin-dependent kinase,CDK)12作为CDKs中的一员,在调节基因转录、RNA剪接和DNA损伤修复等多种细胞进程中发挥重要作用。已有研究发现多种卵巢癌中存在CDK12基因突变,这些都提示了CDK12可作为潜在的治疗靶点。作者在阐述CDK12作用机制的基础上,介绍目前已发现的能够选择性抑制CDK12的试剂,并探讨CDK12抑制剂在多种类型卵巢癌中的治疗进展。

CDK2/4/6抑制剂PF-06873600的合成工艺研究

本研究改进了CDK2/4/6抑制剂PF-06873600的合成工艺。以1-甲基环戊烯(K-1)为起始原料,经还原、手性氨基酸拆分、脱苄胺和取代得到中间体(1R,2R)-2-((5-溴-2-氯嘧啶-4-基)氨基)-1-甲基环戊烷-1-醇(K-3);随后经取代、Heck反应完成吡啶并嘧啶母核结构的合成,得到中间体8-((1R,2R)-2-羟基-2-甲基环戊基)-2-((1-(甲基磺酰基)哌啶-4-基)氨基)吡啶[2,3-d]嘧啶-7(8H)-酮(K-6),再经碘化、与(二氟甲基)三甲基硅烷反应得到目标终产物PF-06873600。以1-甲基环戊烯计,PF-06873600合成总收率为12.4%,终产物HPLC纯度为98.5%(HPLC面积归一化法);目标终产物及关键中间体的结构经MS、~1H NMR确证。该方法较原专利路线相比,反应条件相对温和,后处理操作简便,适合大量制备,可为PF-06873600的生产及其衍生物的合成提供参考。