Inhibition of checkpoint kinase prevents human oocyte apoptosis induced by chemotherapy and allows enhanced tumour chemotherapeutic efficacy.

STUDY QUESTION: Could inhibition of the checkpoint kinase (CHEK) pathway protect human oocytes and even enhance the anti-tumour effects, during chemotherapy? SUMMARY ANSWER: CHEK inhibitors prevented apoptosis of human oocytes induced by chemotherapy and even enhanced the anti-tumour effects. WHAT IS KNOWN ALREADY: CHEK inhibitors showed ovarian protective effects in mice during chemotherapy, while their role in human oocytes is unclear. STUDY DESIGN, SIZE, DURATION: This experimental study evaluated the ovarian reserve of young patients (120 patients) with cancer, exposed or not exposed to taxane and platinum (TP)-combined chemotherapy. Single RNA-sequencing analysis of human primordial oocytes from 10 patients was performed to explore the mechanism of oocyte apoptosis induced by TP chemotherapy. The damaging effects of paclitaxel (PTX) and cisplatin on human oocytes were also evaluated by culturing human ovaries in vitro. A new mouse model that combines human ovarian xenotransplantation and patient-derived tumour xenografts was developed to explore adjuvant therapies for ovarian protection. The mice were randomly allocated to four groups (10 mice for each group): control, cisplatin, cisplatin + CK1 (CHEK1 inhibitor, SCH 900776), and cisplatin + CK2 (CHEK2 inhibitor, BML277). PARTICIPANTS/MATERIALS, SETTING, METHODS: In the prospective cohort study, human ovarian follicles were counted and serum AMH levels were evaluated. RNA-sequencing analysis was conducted, and staining for follicular damage (phosphorylated H2AX histone; γH2AX), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL) assays and assessments of apoptotic biomarkers (western blot and immunofluorescence) were conducted in human ovaries. After the treatments, histological analysis was performed on human ovarian samples to investigate follicular populations, and oocyte damage was measured by γH2AX staining, BAX staining, and TUNEL assays. At the same time, the tumours were evaluated for volume, weight, and apoptosis levels. MAIN RESULTS AND THE ROLE OF CHANCE: Patients who received TP chemotherapy showed decreased ovarian reserves. Single RNA-sequencing analysis of human primordial oocytes indicated that TP chemotherapy induced apoptosis of human primordial oocytes by causing CHEK-mediated TAp63α phosphorylation. In vitro culture of human ovaries showed greater damaging effects on oocytes after cisplatin treatment compared with that after PTX treatment. Using the new animal model, CHEK1/2 inhibitors prevented the apoptosis of human oocytes induced by cisplatin and even enhanced its anti-tumour effects. This protective effect appeared to be mediated by inhibiting DNA damage via the CHEK-TAp63α pathway and by generation of anti-apoptotic signals in the oocytes. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This was a preclinical study performed with human ovarian samples, and clinical research is required for validation. WIDER IMPLICATIONS OF THE FINDINGS: These findings highlight the therapeutic potential of CHEK1/2 inhibitors as a complementary strategy for preserving fertility in female cancer patients. STUDY FUNDING/COMPETING INTEREST(S): This work was financially supported by the National Natural Science Foundation of China (nos. 82001514 and 81902669) and the Fundamental Research Funds for the Central Universities (2021yjsCXCY087). The authors declare no conflict of interest.

Tumor microenvironment promotes lymphatic metastasis of cervical cancer: its mechanisms and clinical implications.

Although previous studies have shed light on the etiology of cervical cancer, metastasis of advanced cervical cancer remains the main reason for the poor outcome and high cancer-related mortality rate. Cervical cancer cells closely communicate with immune cells recruited to the tumor microenvironment (TME), such as lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells. The crosstalk between tumors and immune cells has been clearly shown to foster metastatic dissemination. Therefore, unraveling the mechanisms of tumor metastasis is crucial to develop more effective therapies. In this review, we interpret several characteristics of the TME that promote the lymphatic metastasis of cervical cancer, such as immune suppression and premetastatic niche formation. Furthermore, we summarize the complex interactions between tumor cells and immune cells within the TME, as well as potential therapeutic strategies to target the TME.

Semaphorin 4C regulates ovarian steroidogenesis through RHOA/ROCK1-mediated actin cytoskeleton rearrangement.

Semaphorins are a family of evolutionarily conserved morphogenetic molecules that were initially found to be associated with axonal guidance. Semaphorin 4C (Sema4C), a member of the fourth subfamily of semaphorins, has been demonstrated to play multifaceted and important roles in organ development, immune regulation, tumor growth, and metastasis. However, it is completely unknown whether Sema4C is involved in the regulation of ovarian function. We found that Sema4C was widely expressed in the stroma, follicles, and corpus luteum of mouse ovaries, and its expression was decreased at distinct foci in ovaries of mice of mid-to-advanced reproductive age. Inhibition of Sema4C by the ovarian intrabursal administration of recombinant adeno-associated virus-shRNA significantly reduced oestradiol, progesterone, and testosterone levels in vivo. Transcriptome sequencing analysis showed changes in pathways related to ovarian steroidogenesis and the actin cytoskeleton. Similarly, knockdown of Sema4C by siRNA interference in mouse primary ovarian granulosa cells or thecal interstitial cells significantly suppressed ovarian steroidogenesis and led to actin cytoskeleton disorganization. Importantly, the cytoskeleton-related pathway RHOA/ROCK1 was simultaneously inhibited after the downregulation of Sema4C. Furthermore, treatment with a ROCK1 agonist after siRNA interference stabilized the actin cytoskeleton and reversed the inhibitory effect on steroid hormones described above. In conclusion, Sema4C may play an important role in ovarian steroidogenesis through regulation of the actin cytoskeleton via the RHOA/ROCK1 signaling pathway. These findings shed new light on the identification of dominant factors involved in the endocrine physiology of female reproduction.

Microenvironmentally Responsive Chemotherapeutic Prodrugs and CHEK2 Inhibitors Self-Assembled Micelles: Protecting Fertility and Enhancing Chemotherapy.

Chemotherapy is a widely used and effective adjuvant treatment for cancer, and it has unavoidable damage to female fertility, with statistics showing 38% of women who have received chemotherapy are infertile. How to reduce fertility toxicity while enhancing the oncologic chemotherapy is a clinical challenge. Herein, co-delivery micelles (BML@PMP) are developed, which are composed of a reduction-sensitive paclitaxel prodrug (PMP) for chemotherapy and a CHEK2 inhibitor (BML277) for both fertility protection and chemotherapy enhancement. BML@PMP achieves fertility protection through three actions: (1) Due to the enhanced permeability and retention (EPR) effect, BML@PMP is more enriched in the tumor, while very little in the ovary (about 1/10th of the tumor). (2) Glutathione (GSH) triggers the release of PTX, and with low levels of GSH in the ovary, the amount of PTX released in the ovary is correspondingly reduced. (3) BML277 inhibits oocyte apoptosis by inhibiting the CHEK2-TAp63α pathway. Because of the different downstream targets of CHEK2 in tumor cells and oocytes, BML277 also enhances chemotherapeutic efficacy by reducing DNA damage repair which is activated through the CHEK2 pathway. This bidirectional effect of CHEK2 inhibitor-based co-delivery system represents a promising strategy for improving oncology treatment indices and preventing chemotherapy-associated fertility damage.

The effects and mechanism of taxanes on chemotherapy-associated ovarian damage: A review of current evidence.

Chemotherapy is often a cause of premature ovarian insufficiency and infertility since the ovarian follicles are extremely sensitive to the effects of chemotherapeutic agents. Different chemotherapeutic agents with varying mechanisms of action may damage ovarian function differently. Taxanes are widely used in clinical cancer treatment, but the specific reproductive toxicological information is still controversial. This review described the impact and duration of taxanes on ovarian function in women and analyzed the possible reasons for different conclusions. Furthermore, the toxicity of taxanes on ovarian function and its possible mechanisms were discussed. The potential protective strategies and agents against ovarian damage induced by taxanes are also reviewed.

DDX04+ Stem Cells in the Ovaries of Postmenopausal Women: Existence and Differentiation Potential.

Ovarian aging is a pacemaker with multiple organ dysfunction. Recently, stem cells with the ability to generate new oocytes have been identified, which provides the possibility of stem cell therapy for ovarian aging. Several studies have revealed the existence of stem cells in the human postmenopausal ovary. In this study, we describe a new method using magnetic-activated cell sorting combined with differential adhesion to isolate DDX4+ stem cells from ovaries of postmenopausal women and show that the cells exhibit similar gene expression profiles and growth characteristics with primitive germ cells. Furthermore, the DDX4+ stem cells could enter the meiosis stage and differentiation into oocytes. The RNA-seq data of the differentiated oocytes shows that mitochondrial metabolism may play an important role in the oogenesis process of the DDX4+ stem cells. Through using the human ovarian cortical fragments transplantation model, we indicated that the GFP-DDX4+ stem cells differentiated into some GFP positive oocyte-like structure in vivo. Our study provided a new method for the isolation of DDX4+ stem cells from the ovaries of postmenopausal women and confirmed the ability of these stem cells to differentiate into oocytes.

Machine Learning-Assisted Ensemble Analysis for the Prediction of Response to Neoadjuvant Chemotherapy in Locally Advanced Cervical Cancer.

The clinical benefit of neoadjuvant chemotherapy (NACT) before concurrent chemoradiotherapy (CCRT) vs. adjuvant chemotherapy after CCRT is debated. Non-response to platinum-based NACT is a major contributor to poor prognosis, but there is currently no reliable method for predicting the response to NACT (rNACT) in patients with locally advanced cervical cancer (LACC). In this study we developed a machine learning (ML)-assisted model to accurately predict rNACT. We retrospectively analyzed data on 636 patients diagnosed with stage IB2 to IIA2 cervical cancer at our hospital between January 1, 2010 and December 1, 2020. Five ML-assisted models were developed from candidate clinical features using 2-step estimation methods. Receiver operating characteristic curve (ROC), clinical impact curve, and decision curve analyses were performed to evaluate the robustness and clinical applicability of each model. A total of 30 candidate variables were ultimately included in the rNACT prediction model. The areas under the ROC curve of models constructed using the random forest classifier (RFC), support vector machine, eXtreme gradient boosting, artificial neural network, and decision tree ranged from 0.682 to 0.847. The RFC model had the highest predictive accuracy, which was achieved by incorporating inflammatory factors such as platelet-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio, neutrophil-to-albumin ratio, and lymphocyte-to-monocyte ratio. These results demonstrate that the ML-based prediction model developed using the RFC can be used to identify LACC patients who are likely to respond to rNACT, which can guide treatment selection and improve clinical outcomes.

Recent Advances in Second Near-Infrared Region (NIR-II) Fluorophores and Biomedical Applications.

Fluorescence imaging technique, characterized by high sensitivity, non-invasiveness and no radiation hazard, has been widely applicated in the biomedical field. However, the depth of tissue penetration is limited in the traditional (400-700 nm) and NIR-I (the first near-infrared region, 700-900 nm) imaging, which urges researchers to explore novel bioimaging modalities with high imaging performance. Prominent progress in the second near-infrared region (NIR-II, 1000-1700 nm) has greatly promoted the development of biomedical imaging. The NIR-II fluorescence imaging significantly overcomes the strong tissue absorption, auto-fluorescence as well as photon scattering, and has deep tissue penetration, micron-level spatial resolution, and high signal-to-background ratio. NIR-II bioimaging has been regarded as the most promising in vivo fluorescence imaging technology. High brightness and biocompatible fluorescent probes are crucial important for NIR-II in vivo imaging. Herein, we focus on the recently developed NIR-II fluorescent cores and their applications in the field of biomedicine, especially in tumor delineation and image-guided surgery, vascular imaging, NIR-II-based photothermal therapy and photodynamic therapy, drug delivery. Besides, the challenges and potential future developments of NIR-II fluorescence imaging are further discussed. It is expected that our review will lay a foundation for clinical translation of NIR-II biological imaging, and inspire new ideas and more researches in this field.

Red blood cell membrane-camouflaged nanoparticles loaded with AIEgen and Poly(I : C) for enhanced tumoral photodynamic-immunotherapy.

Red blood cell (RBC)-mimicking nanoparticles (NPs) offer a promising platform for drug delivery because of their prolonged circulation time, reduced immunogenicity and specific targeting ability. Herein, we report the design and preparation of RBC membrane-bound NPs (M@AP), for tumoral photodynamic-immunotherapy. The M@AP is formed by self-assembly of the positively charged aggregation-induced emission luminogen (AIEgen) (named P2-PPh3) and the negatively charged polyinosinic : polycytidylic acid (Poly(I : C)), followed by RBC membrane encapsulation. P2-PPh3 is an AIE-active conjugated polyelectrolyte with additional photosensitizing ability for photodynamic therapy (PDT), while Poly(I : C) serves as an immune-stimulant to stimulate both tumor and immune cells to activate immunity, and thus reduces tumor cell viability. When applied in tumor-bearing mice, the M@AP NPs are enriched in both the tumor region as a result of an enhanced permeability and retention (EPR) effect, and the spleen because of the homing effect of the RBC-mimicking shell. Upon light irradiation, P2-PPh3 promotes strong ROS generation in tumor cells, inducing the release of tumor antigens (TA). The anti-tumor immunity is further enhanced by the presence of Poly(I : C) in M@AP. Thus, this strategy combines the PDT properties of the AIE-active polyelectrolyte and immunotherapy properties of Poly(I : C) to achieve synergistic activation of the immune system for anti-tumor activity, providing a novel strategy for tumor treatment.

Human Umbilical Cord Mesenchymal Stem Cells Improve Ovarian Function in Chemotherapy-Induced Premature Ovarian Failure Mice Through Inhibiting Apoptosis and Inflammation via a Paracrine Mechanism.

Human umbilical cord mesenchymal stem cell (UC-MSC) application is a promising arising therapy for the treatment of premature ovarian failure (POF). However, little is known about the inflammation regulatory effects of human umbilical cord MSCs (UC-MSCs) on chemotherapy-induced ovarian damage, regardless of in vivo or in vitro. This study was designed to investigate the therapeutic effects of UC-MSC transplantation and underlying mechanisms regarding both apoptosis and inflammation in POF mice. The chemotherapy-induced POF models were induced by intraperitoneal injection of cyclophosphamide. Ovarian function parameters, granulosa cell (GC) apoptosis, and inflammation were examined. Morphological staining showed that UC-MSC treatment increased the ovary size, and the numbers of primary and secondary follicles, but decreased the number of atretic follicles. Estradiol levels in the UC-MSC-treated group were increased while follicle-stimulating hormone levels were reduced compared to those in the POF group. UC-MSCs inhibited cyclophosphamide-induced GC apoptosis and inflammation. Meanwhile, phosphorylation of AKT and P38 was elevated after UC-MSC treatment. Tracking of UC-MSCs in vivo indicated that transplanted UC-MSCs were only located in the interstitium of ovaries rather than in follicles. Importantly, UC-MSC-derived extracellular vesicles protected GCs from alkylating agent-induced apoptosis and inflammation in vitro. Our results suggest that UC-MSC transplantation can reduce ovary injury and improve ovarian function in chemotherapy-induced POF mice through anti-apoptotic and anti-inflammatory effects via a paracrine mechanism.

THERAPY OF ENDOCRINE DISEASE: Novel protection and treatment strategies for chemotherapy-associated ovarian damage.

Fertility and ovarian protection against chemotherapy-associated ovarian damage has formed a new field called oncofertility, which is driven by the pursuit of fertility protection as well as good life quality for numerous female cancer survivors. However, the choice of fertility and ovarian protection method is a difficult problem during chemotherapy and there is no uniform guideline at present. To alleviate ovarian toxicity caused by anticancer drugs, effective methods combined with an individualized treatment plan that integrates an optimal strategy for preserving and restoring reproductive function should be offered from well-established to experimental stages before, during, and after chemotherapy. Although embryo, oocyte, and ovarian tissue cryopreservation are the major methods that have been proven effective and feasible for fertility protection, they are also subject to many limitations. Therefore, this paper mainly discusses the future potential methods and corresponding mechanisms for fertility protection in chemotherapy-associated ovarian damage.

Specific Small-Molecule NIR-II Fluorescence Imaging of Osteosarcoma and Lung Metastasis.

Osteosarcoma is an aggressive tumor of mesenchymal origin that is more likely to spread to the lung than others, with a major impact on patients' prognosis. The optimal imaging method that can reliably detect or exclude pulmonary metastases from osteosarcoma is still scarce. Herein, two homologous types of fluorescent probes CH1055-PEG-PT and CH1055-PEG-Affibody, which show highly promising results for targeting imaging of osteosarcoma and its lung metastasis, respectively, are designed and synthesized. It is found that the NIR-II imaging quality of CH1055-PEG-PT is far superior to that of computed tomography for the early in vivo 143B tumor imaging, and this probe-guided surgery for accurate resection of 143B tumor is further performed. The high-resolution visualization of primary and micrometastatic lung lesions of osteosarcoma by using CH1055-PEG-Affibody is also demonstrated. Therefore, the attractive imaging properties of CH1055-PEG-PT and CH1055-PEG-Affibody, including high levels of uptakes, and high spatial and temporal resolution, open up opportunities for molecular imaging and clinical translation of osteosarcoma and its lung metastasis in the unique second near-infrared window.

A bright NIR-II fluorescent probe for breast carcinoma imaging and image-guided surgery.

A novel bright near-infrared II (NIR-II, 1000-1700 nm) fluorescent probe with excellent water-solubility, superior photostability, and excellent in vitro and in vivo biocompatibility was facilely synthesized for in vivo biomedical imaging of xenograft breast tumor and chemically induced spontaneous breast carcinoma. To the best of our knowledge, it is the first time that the superior practical applications of this NIR-II probe in dimethylbenzanthracene (DMBA)-induced rat mammary carcinoma imaging and image-guided rat carcinoma surgery were demonstrated.

Correction: A bright NIR-II fluorescent probe for breast carcinoma imaging and image-guided surgery.

Correction for 'A bright NIR-II fluorescent probe for breast carcinoma imaging and image-guided surgery' by Xiaodong Zeng et al., Chem. Commun., 2019, DOI: .

Resveratrol alleviates chemotherapy-induced oogonial stem cell apoptosis and ovarian aging in mice.

Chemotherapy-induced ovarian aging not only increases the risk for early menopause-related complications but also results in infertility in young female cancer survivors. Oogonial stem cells have the ability to generate new oocytes and thus provide new opportunities for treating ovarian aging and female infertility. Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural phenol derived from plants, that has been shown to have positive effects on longevity and redox flow in lipid metabolism and a preventive function against certain tumors. To evaluate whether resveratrol could promote the repair of oogonial stem cells damage in a busulfan/cyclophosphamide (Bu/Cy)-induced accelerated ovarian aging model, female mice were administered 30 and 100 mg/kg/d resveratrol through a gavage for 2 weeks. We demonstrated that resveratrol (30 mg/kg/d) relieved oogonial stem cells loss and showed an attenuating effect on Bu/Cy-induced oxidative apoptosis in mouse ovaries, which may be attributed to the attenuation of oxidative levels in ovaries. Additionally, we also showed that Res exerted a dose-dependent effect on oogonial stem cells and attenuated H2O2-induced cytotoxicity and oxidative stress injury by activating Nrf2 in vitro. Therefore, resveratrol could be of a potential therapeutic drug used to prevent chemotherapy-induced ovarian aging.