Clinical development of WEE1 inhibitors in gynecological cancers: A systematic review

Targeting WEE1 in tumor-associated dendritic cells potentiates antitumor immunity via the cGAS/STING pathway

DNA damage profoundly affects cancer progression and immune cell function. While research primarily focuses on tumor cells, the effects of DNA damage on immune cells remain understudied. Here, we observe significant DNA damage in tumor-associated dendritic cells (TADCs), accompanied by the upregulation of the serine/threonine kinase WEE1, a crucial regulator of DNA damage repair. Interestingly, DNA damage also stimulates DC activation. WEE1 inhibition activates TADCs through the cGAS/STING pathway, increasing IL-12 and type I interferon expression, thus enhancing the antitumor immune response and improving tumor control. Additionally, WEE1 inhibition augments the efficacy of DC vaccines and synergizes with immune checkpoint blockade therapy. These findings highlight a pivotal role of WEE1 signaling in DNA damage repair in DCs within the tumor microenvironment, which in turn suppresses the antitumor immune response. Therefore, targeting WEE1 in DCs represents a promising approach to enhance T cell activation and improve the effectiveness of cancer immunotherapy.

Cyclin E1 overexpression sensitizes ovarian cancer cells to WEE1 and PLK1 inhibition

Cyclin E1 (CCNE1) amplification is associated with poor prognosis of ovarian carcinomas across histological subtypes. Inhibitors targeting PLK1 or WEE1 are emerging as promising therapeutic agents for cancer treatment that disrupt the critical G2/M checkpoint, leading to cancer cell death. However, biomarkers that predict the response to these inhibitors are not well defined. Here, we evaluated the efficacy of the PLK1 inhibitor, volasertib, and the WEE1 inhibitor, adavosertib, along with the biomarker potential of cyclin E1 in ovarian cancer cells. Both inhibitors suppressed the proliferation of cyclin E1-overexpressing cells to a greater extent than that of cells exhibiting low cyclin E1 expression. TP53 silencing did not increase the sensitivity to these inhibitors. In cyclin E1-overexpressing cells, PLK1 inhibition reduced the proportion of cells in the G1 phase and increased those in the G2/M and sub-G1 phases. WEE1 inhibition reduced G1 phase cells without a clear peak in the S-G2/M phase and increased the sub-G1 phase cells. Both inhibitors suppressed the growth of cyclin E1-overexpressing tumors in vivo. Taken together, cyclin E1 overexpression, regardless of TP53 status, may serve as a predictive biomarker for the efficacy of these inhibitors, offering potential personalized treatment strategies for ovarian cancer.

PARP inhibitors in ovarian cancer: Mechanisms of resistance and implications to therapy

Advanced epithelial ovarian cancer of the high-grade serous subtype (HGSOC) remains a significant clinical challenge due to the development of resistance to current platinum-based chemotherapies. PARP1/2 inhibitors (PARPi) exploit the well-characterised homologous recombination repair deficiency (HRD) in HGSOC and offer an effective targeted approach to treatment. Several clinical trials demonstrated that PARPi (olaparib, rucaparib, niraparib) significantly improved progression-free survival (PFS) in HGSOC in the recurrent maintenance setting. However, 40-70 % of patients develop Resistance to PARPi presenting an ongoing challenge in the clinic. Therefore, there is an unmet need for novel targeted therapies and biomarkers to identify intrinsic or acquired resistance to PARPi in ovarian cancer. Understanding the mechanisms of resistance to PARPi is crucial for identifying molecular vulnerabilities, developing effective biomarkers for patient stratification and guiding treatment decisions. Here, we summarise the current landscape of mechanisms associated with PARPi resistance such as restored homologous recombination repair functionality, replication fork stability and alterations to PARP1 and PARP2 and the DNA damage response. We highlight the role of circulating tumour DNA (ctDNA) in identifying acquired resistance biomarkers and its potential in guiding 'real-time' treatment decisions. Moreover, we explore other innovative treatment strategies aimed at overcoming specific resistance mechanisms, including the inhibition of ATR, WEE1 and POLQ. We also examine the role of PARPi rechallenge in patients with acquired resistance.

Discovery of WEE1 Kinase Inhibitors with Potent Activity against Patient-Derived, Metastatic Colorectal Cancer Organoids

A library of potent WEE1 kinase inhibitors was synthesized based on the discontinued frontrunner clinical candidate AZD1775 (1), many of which were more selective for WEE1 over an undesirable off-target of 1, the kinase PLK1. When tested against patient-derived organoids (PDOs) grown from TP53-mutated colorectal cancer (CRC) peritoneal metastases, 34 (IC50 value of 62 nM) exhibited stronger efficacy than 1 (IC50 value of 120 nM) and the best-in-class clinical candidate ZN-c3 (IC50 value of 127 nM). Against primary CRC PDOs with TP53-WT, 34 significantly enhanced DNA damage, replication stress and apoptosis compared to 1, as well as demonstrated high selectivity over patient-matched normal healthy colon PDOs, highlighting a potential therapeutic window for cancer treatment. Overall, this investigation provides critical insight into several potent WEE1 inhibitors that exhibited exceptional efficacy against CRC PDOs and is the first to utilize a PDO platform to assess their effect on healthy and malignant cell viability.

Characterization of G2/M checkpoint classifier for personalized treatment in uterine corpus endometrial carcinoma

BACKGROUND

Uterine Corpus Endometrial Carcinoma (UCEC) is a highly heterogeneous tumor, and limitations in current diagnostic methods, along with treatment resistance in some patients, pose significant challenges for managing UCEC. The excessive activation of G2/M checkpoint genes is a crucial factor affecting malignancy prognosis and promoting treatment resistance.

METHODS

Gene expression profiles and clinical feature data mainly came from the TCGA-UCEC cohort. Unsupervised clustering was performed to construct G2/M checkpoint (G2MC) subtypes. The differences in biological and clinical features of different subtypes were compared through survival analysis, clinical characteristics, immune infiltration, tumor mutation burden, and drug sensitivity analysis. Ultimately, an artificial neural network (ANN) and machine learning were employed to develop the G2MC subtypes classifier.

RESULTS

We constructed a classifier based on the overall activity of the G2/M checkpoint signaling pathway to identify patients with different risks and treatment responses, and attempted to explore potential therapeutic targets. The results showed that two G2MC subtypes have completely different G2/M checkpoint-related gene expression profiles. Compared with the subtype C2, the subtype C1 exhibited higher G2MC scores and was associated with faster disease progression, higher clinical staging, poorer pathological types, and lower therapy responsiveness of cisplatin, radiotherapy and immunotherapy. Experiments targeting the feature gene KIF23 revealed its crucial role in reducing HEC-1A sensitivity to cisplatin and radiotherapy.

CONCLUSION

In summary, our study developed a classifier for identifying G2MC subtypes, and this finding holds promise for advancing precision treatment strategies for UCEC.

WEE1 Inhibition by AZD1775 Augments Colorectal Cancer Cells Susceptibility to VE-822-induced DNA Damage and Apoptosis

WEE1 is a key tyrosine kinase involved in the cell cycle regulation with potent anticancer effects in various cancer types including colorectal cancer. Recent studies have focused on the potential of combinational inhibition of Ataxia Telangiectasia and Rad-3-related protein (ATR) and WEE1 in increasing apoptosis in cancer cells. Therefore, this study investigates the effects of inhibiting WEE1, by employing AZD1775, on colorectal cancer cells' susceptibility to VE-822-induced DNA damage and apoptosis.SW-480 and HT-29 cells were treated with AZD1775 and VE-822, alone and in combination. MTT assay was used to assess cell proliferation and viability. The mRNA levels of ATR, checkpoint kinase 1 (CHK1), WEE1, ribonucleotide reductase (RR) catalytic subunit M1 (RRM1) and RRM2 were measured by qRT-PCR. Cellular γ-(H2A histone family member X) H2AX levels were measured by Western blot. Analyses were conducted using ELISA to assess 8-Oxo-2'-deoxyguanosine (8-oxo-dG) levels. Lactate dehydrogenase (LDH) and ELISA death assays were used to assess apoptosis.The SW-480 and HT-29 cells have low proliferation rate when treated with VE-822 and AZD1775. The IC50 value for VE-822 was 1.3 μM and 1.6 μM in SW480 and HT-29, respectively. Also, this value for AZD1775 in SW480 was 140 nM and in HT-29 was 185 nM. The expression levels of ATR, CHK1, WEE1, RRM1, and RRM2 were significantly downregulated in both cell lines treated with combination of VE-822 and AZD1775 (P<0.05). DNA damage markers, including γ-H2AX and 8-oxo-dG were upregulated in these cells. Simultaneous treatment with VE-822 and AZD177 increased apoptosis capacity of both cell lines.The inhibition of WEE1 via AZD1775 potentiated the anticancer effects of ATR inhibitor, VE-822, in combating colorectal cancer via targeting DNA damage.

Targeting chromosomal instability in patients with cancer

Chromosomal instability (CIN) is a hallmark of cancer and a driver of metastatic dissemination, therapeutic resistance, and immune evasion. CIN is present in 60-80% of human cancers and poses a formidable therapeutic challenge as evidenced by the lack of clinically approved drugs that directly target CIN. This limitation in part reflects a lack of well-defined druggable targets as well as a dearth of tractable biomarkers enabling direct assessment and quantification of CIN in patients with cancer. Over the past decade, however, our understanding of the cellular mechanisms and consequences of CIN has greatly expanded, revealing novel therapeutic strategies for the treatment of chromosomally unstable tumours as well as new methods of assessing the dynamic nature of chromosome segregation errors that define CIN. In this Review, we describe advances that have shaped our understanding of CIN from a translational perspective, highlighting both challenges and opportunities in the development of therapeutic interventions for patients with chromosomally unstable cancers.

Advanced Design, Synthesis, and Evaluation of Highly Selective Wee1 Inhibitors: Enhancing Pharmacokinetics and Antitumor Efficacy

Wee1 is a kinase that regulates cell cycle arrest in response to DNA damage. Wee1 inhibition is a potential strategy to suppress the growth of tumors with defective p53 or DNA repair pathways. However, the development of Wee1 inhibitors faces some challenges. AZD1775, the first-in-class Wee1 inhibitor, has poor kinase selectivity and dose-limiting toxicity. Here, we report the discovery of 12h, a highly selective and potent Wee1 inhibitor with a favorable pharmacokinetic profile. 12h showed strong antiproliferative effects against Lovo cells, a colorectal cancer cell line, both in vitro and in vivo. Moreover, 12h showed a clean kinase profile and effectively induced cell apoptosis. Our results suggest that 12h is a promising drug candidate for further development as a novel anticancer agent.

Targeting WEE1 Kinase in Gynecological Malignancies

WEE1 kinase is involved in the G2/M cell cycle checkpoint control and DNA damage repair. A functional G2/M checkpoint is crucial for DNA repair in cancer cells with p53 mutations since they lack a functional G1/S checkpoint. Targeted inhibition of WEE1 kinase may cause tumor cell apoptosis, primarily, in the p53-deficient tumor, via bypassing the G2/M checkpoint without properly repairing DNA damage, resulting in genome instability and chromosomal deletion. This review aims to provide a comprehensive overview of the biological role of WEE1 kinase and the potential of WEE1 inhibitor (WEE1i) for treating gynecological malignancies. We conducted a thorough literature search from 2001 to September 2023 in prominent databases such as PubMed, Scopus, and Cochrane, utilizing appropriate keywords of WEE1i and gynecologic oncology. WEE1i has been shown to inhibit tumor activity and enhance the sensitivity of chemotherapy or radiotherapy in preclinical models, particularly in p53-mutated gynecologic cancer models, although not exclusively. Recently, WEE1i alone or combined with genotoxic agents has confirmed its efficacy and safety in Phase I/II gynecological malignancies clinical trials. Furthermore, it has become increasingly clear that other inhibitors of DNA damage pathways show synthetic lethality with WEE1i, and WEE1 modulates therapeutic immune responses, providing a rationale for the combination of WEE1i and immune checkpoint blockade. In this review, we summarize the biological function of WEE1 kinase, development of WEE1i, and outline the preclinical and clinical data available on the investigation of WEE1i for treating gynecologic malignancies.

Telomere-related DNA damage response pathways in cancer therapy: prospective targets

Maintaining the structural integrity of genomic chromosomal DNA is an essential role of cellular life and requires two important biological mechanisms: the DNA damage response (DDR) mechanism and telomere protection mechanism at chromosome ends. Because abnormalities in telomeres and cellular DDR regulation are strongly associated with human aging and cancer, there is a reciprocal regulation of telomeres and cellular DDR. Moreover, several drug treatments for DDR are currently available. This paper reviews the progress in research on the interaction between telomeres and cellular DNA damage repair pathways. The research on the crosstalk between telomere damage and DDR is important for improving the efficacy of tumor treatment. However, further studies are required to confirm this hypothesis.

Homologous recombination proficient subtypes of high-grade serous ovarian cancer: treatment options for a poor prognosis group

Approximately 50% of tubo-ovarian high-grade serous carcinomas (HGSCs) have functional homologous recombination-mediated (HR) DNA repair, so-called HR-proficient tumors, which are often associated with primary platinum resistance (relapse within six months after completion of first-line therapy), minimal benefit from poly(ADP-ribose) polymerase (PARP) inhibitors, and shorter survival. HR-proficient tumors comprise multiple molecular subtypes including cases with CCNE1 amplification, AKT2 amplification or CDK12 alteration, and are often characterized as "cold" tumors with fewer infiltrating lymphocytes and decreased expression of PD-1/PD-L1. Several new treatment approaches aim to manipulate these negative prognostic features and render HR-proficient tumors more susceptible to treatment. Alterations in multiple different molecules and pathways in the DNA damage response are driving new drug development to target HR-proficient cancer cells, such as inhibitors of the CDK or P13K/AKT pathways, as well as ATR inhibitors. Treatment combinations with chemotherapy or PARP inhibitors and agents targeting DNA replication stress have shown promising preclinical and clinical results. New approaches in immunotherapy are also being explored, including vaccines or antibody drug conjugates. Many approaches are still in the early stages of development and further clinical trials will determine their clinical relevance. There is a need to include HR-proficient tumors in ovarian cancer trials and to analyze them in a more targeted manner to provide further evidence for their specific therapy, as this will be crucial in improving the overall prognosis of HGSC and ovarian cancer in general.

New horizons for platinum-resistant ovarian cancer: insights from the 2023 American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) Annual Meetings

Platinum-resistant ovarian cancer is difficult to treat and has a poor prognosis. Patients with platinum-resistant ovarian cancer have limited treatment options and often have a limited benefit from existing chemotherapeutic agents. There is a lack of contemporary effective anticancer drugs and reliable predictive biomarkers for this aggressive cancer. Recent cutting-edge research presented at the 2023 American Society of Clinical Oncology (ASCO) and the European Society for Medical Oncology (ESMO) Annual Meetings has provided insights into several potential therapeutic targets, such as DNA damage repair proteins, cell-cycle regulators, and immune-modulating agents. In addition, antibody-drug conjugates have provided new practice-changing results in platinum-resistant ovarian cancer. Here, we review the results of research presented at this annual event, with a focus on clinical trials investigating novel treatment approaches for platinum-resistant ovarian cancer, in addition to predictive and prognostic biomarkers for optimal patient selection, and other topics, such as real-world evidence.

Synergistic effect of adavosertib and fimepinostat on acute myeloid leukemia cells by enhancing the induction of DNA damage

In recent years, a number of novel pharmaceutical agents have received approval for the management of acute myeloid leukemia (AML). However, there is still ample opportunity for enhancing efficacy. The Wee1 inhibitor adavosertib (ADA) shows promise for the treatment of AML. Based on the effect of drugs on DNA damage, we conducted a combination study involving ADA and fimepinostat (CUDC-907), a dual inhibitor of PI3K and histone deacetylase (HDAC). We observed that the combination of CUDC-907 and ADA exhibited a synergistic effect in enhancing the antileukemic activity in both AML cell lines and primary patient samples, demonstrating through flow cytometry analysis and MTT assay, respectively. Additionally, our study revealed that CUDC-907 has the ability to augment ADA-induced DNA damage, as determined by the measurement of γH2AX levels and the implementation of the alkaline comet assay. Through the utilization of western blotting analyses, targeted inhibitors, and ectopic overexpression, we propose that the downregulation of Wee1, CHK1, RNR, and c-Myc are the potential mechanisms. Our data support the development of ADA in combination with CUDC-907 for the treatment of AML.

Novel Therapeutics in Ovarian Cancer: Expanding the Toolbox

Despite high response rates to initial therapy, most patients with ovarian cancer will ultimately recur and go on to develop resistance to standard treatments. Novel therapies have been developed to overcome drug resistance and alter the tumor immune microenvironment by targeting oncogenic pathways, activating the innate immune response, and enhancing drug delivery. In this review, we discuss the current and future roles of chemotherapy, targeted agents such as poly (ADP-ribose) polymerase (PARP) inhibitors, bevacizumab, and mirvetuximab in the treatment of ovarian cancer. We explore the emerging role of therapeutic targets, including DNA repair pathway inhibitors and novel antibody-drug conjugates. Furthermore, we delve into the role of immunotherapeutic agents such as interleukins as well as immune-promoting agents such as oncolytic viruses and cancer vaccines. Innovative combination therapies using these agents have led to a rapidly evolving treatment landscape and promising results for patients with recurrent ovarian cancer.