Targeting angiogenesis in endometrial cancer - new agents for tailored treatments

An updated review of small-molecule HPK1 kinase inhibitors (2016-present)

Hematopoietic progenitor kinase 1 (HPK1) is a serine-threonine kinase specific to hematopoiesis and a member of the MAP4K family of Ste20-related protein kinases. Targeting HPK1 to ameliorate T cell exhaustion and enhance T cell functions is a promising strategy for clinical immunotherapies. Numerous studies have reported the progress in developing effective HPK1 inhibitors and elucidating their mechanisms of action. However, most inhibitors affect multiple signaling pathways, resulting in unintended side effects that limit their clinical development and application. Herein, we reviewed HPK1-related signaling pathways, clinical candidates and recent advances in small-molecule inhibitors targeting HPK1. Additionally, we present our perspectives on current challenges and potential future research field, hoping to provide inspiration for the development of novel HPK1 inhibitors.

Combat Against Gynecological Cancers with Blood Vessels as Entry Point: Anti-Angiogenic Drugs, Clinical Trials and Pre-Clinical Nano-Delivery Platforms

Angiogenesis is an essential mechanism for the progression of gynecological cancers. Although approved anti-angiogenic drugs have demonstrated clinical efficacy in treating gynecological cancers, the full potential of therapeutic strategies based on tumor blood vessels has not yet been realized. This review summarizes the latest angiogenesis mechanisms involved in the progression of gynecological cancers and discusses the current clinical practice of approved anti-angiogenic drugs and related clinical trials. Given the close relationship between gynecological cancers and blood vessels, we highlight more delicate strategies for regulating tumor vessels, including wise drug combinations and smart nano-delivery platforms to achieve highly efficient drug delivery and overall vessel microenvironment regulation. We also address current challenges and future opportunities in this field. We aim to generate interest in therapeutic strategies that target blood vessels as a key entry point and offer new potential and inspiration for combating gynecological cancers.

Anti-angiogenic therapy in ovarian cancer: Current understandings and prospects of precision medicine

Ovarian cancer (OC) remains the most fatal disease of gynecologic malignant tumors. Angiogenesis refers to the development of new vessels from pre-existing ones, which is responsible for supplying nutrients and removing metabolic waste. Although not yet completely understood, tumor vascularization is orchestrated by multiple secreted factors and signaling pathways. The most central proangiogenic signal, vascular endothelial growth factor (VEGF)/VEGFR signaling, is also the primary target of initial clinical anti-angiogenic effort. However, the efficiency of therapy has so far been modest due to the low response rate and rapidly emerging acquiring resistance. This review focused on the current understanding of the in-depth mechanisms of tumor angiogenesis, together with the newest reports of clinical trial outcomes and resistance mechanism of anti-angiogenic agents in OC. We also emphatically summarized and analyzed previously reported biomarkers and predictive models to describe the prospect of precision therapy of anti-angiogenic drugs in OC.

Observation of the therapeutic effect of apatinib in advanced platinum-resistant recurrent epithelial ovarian cancer

BACKGROUND

Apatinib is an oral anti-angiogenic drug that mainly targets vascular endothelial growth factor receptor 2 (VEGFR-2) and is widely used in a variety of solid tumours. The purpose of this study is to evaluate the clinical efficacy and safety of apatinib in patients with advanced platinum-resistant relapsed epithelial ovarian cancer (EOC).

METHODS

A retrospective analysis was performed, the clinical data of patients with stage IIIC-IV platinum-resistant relapsed EOC between January 2014 and May 2018 were collected. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were reviewed and evaluated. The propensity score matching (PSM) method was used to determine the final case data included in this study.

RESULTS

According to 1:2 propensity matching, 108 patients were finally taken into account: 36 in the apatinib group and 72 in the control group. The follow-up ended in January 2019, and the median follow-up time was 28 months. In the apatinib group, ORR was 30.56% and DCR was 66.67%, whereas in the control group, ORR was 16.67% and DCR was 44.44%. In the apatinib group, median PFS was 6.0 months (95% CI 3.69-8.31) and median OS was 15.8 months (95% CI 6.99-24.6), while in the control group, median PFS was 3.3 months (95% CI 2.44-4.16) and median OS was 9.2 months (95% CI 6.3-12.06); the difference was statistically significant (P < 0.05). Apatinib was more effective than conventional chemotherapy in reducing the risk of PFS [HR 0.40 (95% CI 0.22-0.76), P = 0.0017] and OS [HR 0.40 (95% CI 0.21-0.73), P = 0.002]. Multivariate Cox analysis showed that the course of treatment and decrease in serum CA125 levels are independent risk factors for PFS in patients, while apatinib, the length of treatment course and the location of the lesion are independent risk factors for recurrence affecting the OS of patients. The main grade 3-4 adverse events in the apatinib group were hypertension, hand-foot syndrome, and oral mucosal ulcers, and all adverse events were controllable.

CONCLUSION

Apatinib was found to be both safe and effective in patients with advanced platinum-resistant relapsed EOC. More in-depth clinical research and applications should be carried out.

Facts and Hopes in Immunotherapy of Endometrial Cancer

Immunotherapy with checkpoint inhibitors has changed the paradigm of treatment for many tumors, and endometrial carcinoma is not an exception. Approved treatment options are pembrolizumab or dostarlimab for mismatch repair deficient tumors, pembrolizumab for tumors with high mutational load, and, more recently, pembrolizumab/lenvatinib for all patients with endometrial cancer. Endometrial cancer is a heterogeneous disease with distinct molecular subtypes and different prognoses. Differences between molecular subgroups regarding antigenicity and immunogenicity should be relevant to develop more tailored immunotherapeutic approaches. In this review, we aim to summarize and discuss the current evidence-Facts, and future opportunities-Hopes-of immunotherapy for endometrial cancer, focusing on relevant molecular and tumor microenvironment features of The Cancer Genome Atlas endometrial cancer subtypes.

Anlotinib in recurrent or metastatic endometrial cancer

OBJECTIVE

For recurrent or metastatic endometrial cancer after second-line treatment, therapeutic options are limited. Anlotinib is a new multi-targeted tyrosine kinase inhibitor of tumor angiogenesis and growth. The aim of this study was to explore the efficacy and safety of anlotinib in patients with recurrent or metastatic endometrial cancer.

METHODS

Patients with recurrent or metastatic endometrial cancer who received anlotinib or anlotinib plus pembrolizumab after second-line treatment between July 2017 and October 2020 were analyzed. Objective response rate, disease control rate, progression-free survival, overall survival, and safety were evaluated.

RESULTS

A total of 56 patients were analyzed. The median age was 62 years (range 42-80). The median treatment of anlotinib was 5.9 cycles (range 2-21). The overall objective response rate was 42.9%, and the disease control rate was 75%. 44 (78.6%) patients received anlotinib monotherapy and 12 (21.2%) patients received anlotinib plus pembrolizumab. The objective response rate was 40.9% versus 50% (p=0.52) and the disease control rate was 72.7% versus 83.3% (p=0.59) in the monotherapy group and the combination therapy group, respectively. The median progression-free survival and overall survival from initiation of anlotinib therapy was 6 months (95% CI 4.89 to 7.11) and 13.3 months (95% CI 9.94 to 16.61), respectively. On multivariable Cox analysis, age (>60 vs ≤60 years) was an independent impact factor for both progression-free survival and overall survival, while prior lines of treatment (2 lines vs ≥3 lines) was an independent predictor of progression-free survival. The incidences of grade 3/4 adverse events were hypertension (10.7%), fatigue (7.1%), hand-foot syndrome (7.1%), proteinuria (3.6%), sore throat (3.6%), and hypothyroidism (3.6%).

CONCLUSION

Anlotinib is effective and well tolerated in patients with recurrent or metastatic endometrial cancer. It may be considered a choice for patients younger than 60 years and who have had <3 lines of treatment.

Endothelial cell-specific molecule 1 (ESM1) promoted by transcription factor SPI1 acts as an oncogene to modulate the malignant phenotype of endometrial cancer

We aimed to study the function and mechanism of endothelial cell-specific molecule 1 (ESM1) in endometrial cancer (EC). The binding relationship between SPI1 and ESM1 was predicted by bioinformatics analysis and verified by the dual-luciferase reporter assay. The expressions and effects of SPI1 and ESM1 were determined using quantitative real-time PCR, immunohistochemistry, Western blot, and functional experiments. ESM1 was highly expressed in EC and was associated with the poor prognosis of patients. ESM1 silencing suppressed the viability, proliferation, invasion, and angiogenesis of EC cells, down-regulated expressions of PCNA, N-cadherin, Vimentin, VEGFR-1, VEGFR2, and EGFR, but upregulated E-cadherin level, while ESM1 overexpression did oppositely. Moreover, SPI1 bound to ESM1. Overexpressed SPI1 promoted the expression of ESM1 and induced malignant phenotype (viability, proliferation, and invasion), which were countervailed by ESM1 silencing. Collectively, ESM1 induced by SPI1 promotes the malignant phenotype of EC.

A phase III randomized, controlled trial of nedaplatin versus cisplatin concurrent chemoradiotherapy in patients with cervical cancer

BACKGROUND

We evaluated the non-inferiority of nedaplatin-based and cisplatin-based concurrent chemoradiotherapy in cervical cancer patients.

DESIGN

Patients aged 28-82 years with pathologically diagnosed cervical cancer (stage IB-IVA) were randomly chosen for the study. Patients in both the cisplatin and nedaplatin groups received radiotherapy and weekly intravenous nedaplatin 30 mg/m² or cisplatin 40 mg/m² concurrently.

RESULTS

One hundred and sixty patients who received treatment between 10 May 2018 and 31 August 2020 were included. The 3-year overall survival in the nedaplatin group (median 30.5 months) was not significantly different from that in the cisplatin group (28.5 months; hazard ratio 0.131, 95% confidence interval 0.016-1.068; P = 0.058). No significant differences in hematological toxicity were observed between the two groups. Vomiting (40 versus 61), nausea (44 versus 67), and anorexia (52 versus 71) were more common in the cisplatin group whereas effects on liver function, including total bilirubin (7 versus 3), alanine aminotransferase (7 versus 2), and aspartate aminotransferase (6 versus 2), were more common in the nedaplatin group. Four patients in the cisplatin group had grade I creatinine elevation, whereas none in the nedaplatin group had abnormal creatinine levels. Two patients in the nedaplatin group discontinued concurrent chemotherapy because of infusion, and one patient in the cisplatin group discontinued treatment because of infusion-induced dizziness.

CONCLUSIONS

Our findings suggest that nedaplatin has a milder gastrointestinal reaction but a more significant effect on liver function than cisplatin. In patients with cervical cancer, nedaplatin-based concurrent chemoradiotherapy could serve as an alternative treatment to cisplatin.

The Value of Intratumoral and Extratumoral Microvessel Density for the Tumor-dominated Area in the Endometrial Carcinoma

OBJECTIVE

Microvessel density (MVD) measuring angiogenesis can influence clinicopathologic variables in endometrial carcinoma (EC). MVD is usually assessed in the densest vascular area the tumor, but the distinction between intratumoral and extratumoral MVD is not reported, and tumor-dominated area is not examined for MVD in the EC in the literature.

MATERIALS AND METHODS

A total of 151 cases with EC, which had hysterectomy from 2005 to 2020, were included. All histopathologic parameters were re-evaluated blindly. MVD was counted in the intratumoral (densest tumoral and vascular area) and extratumoral (periphery of the tumor, tumor invasion tip, densest tumoral, and vascular area) areas using immunohistochemical CD31 expression.

RESULTS

Large tumor size, deep myometrial invasion, high grade, nonendometrioid tumor type, cervix invasion, lymph node metastasis, human epidermal growth factor receptor 2 positivity, stage III to IV, substantial lymphovascular invasion, and overall survival had significant relations with intratumoral and extratumoral MVD ( P <0.05). Age and lymphoplasmacytic inflammation showed marginal significance for extratumoral MVD. Extratumoral and intratumoral MVD had high (near-perfect) agreement (κ=0.870, P =0.001). Cervix invasion, stage III to IV, high grade, intratumoral, and extratumoral MVD were correlated with lower overall survival in the multivariate analyses.

CONCLUSION

High MVD had an impact on the behavior and prognosis of EC and may be a potential indicator for antiangiogenic treatments for aggressive tumors. Although intratumoral and extratumoral MVD in the tumor-dominated area have mostly similar effects in our study, this situation can be cleared more by further investigations.

Metabolic Reprogramming Induces Macrophage Polarization in the Tumor Microenvironment

Macrophages are one of the most important cells in the innate immune system, they are converted into two distinct subtypes with completely different molecular phenotypes and functional features under different stimuli of the microenvironment: M1 macrophages induced by IFN-γ/lipopolysaccharides(LPS) and M2 macrophages induced by IL-4/IL-10/IL-13. Tumor-associated macrophages (TAMs) differentiate from macrophages through various factors in the tumor microenvironment (TME). TAMs have the phenotype and function of M2 macrophages and are capable of secreting multiple cytokines to promote tumor progression. Both tumor cells and macrophages can meet the energy needs for rapid cell growth and proliferation through metabolic reprogramming, so a comprehensive understanding of pro-tumor and antitumor metabolic switches in TAM is essential to understanding immune escape mechanisms. This paper focuses on the functions of relevant signaling pathways and cytokines during macrophage polarization and metabolic reprogramming, and briefly discusses the effects of different microenvironments and macrophage pathogenicity, in addition to describing the research progress of inhibitory drugs for certain metabolic and polarized signaling pathways.

Antiangiogenic Strategies in Epithelial Ovarian Cancer: Mechanism, Resistance, and Combination Therapy

Angiogenesis is one of the hallmarks of cancer and plays a crucial role in carcinogenesis and progression of epithelial ovarian cancer. Antiangiogenic agent is the first approved targeted agent in ovarian cancer. Anti-angiogenic agents mainly include agents target VEGF/VEGFR pathway, such as bevacizumab and agents target receptor tyrosine kinase, and non-VEGF/VEGFR targets of angiogenesis. Antiangiogenic agents demonstrate certain effects in ovarian cancer treatment either as monotherapy or combined with chemotherapy. Unfortunately, antiangiogenic agents, such as bevacizumab, integrated into the ovarian cancer treatment paradigm do not increase cures. Thus, the benefits of anti-angiogenic agents must be carefully weighed against the cost and associated toxicities. Antiangiogenic agents drug resistance and short of predictive biomarkers are main obstacles in ovarian cancer treatment. A combination of poly (ADP-ribose) polymerase inhibitors or immune checkpoint inhibitors might be great strategies to overcome resistance as well as enhance anti-tumor activity of anti-angiogenic drugs. Predictive biomarkers of antiangiogenic agents are in urgent need.

Angiogenesis: A Pivotal Therapeutic Target in the Drug Development of Gynecologic Cancers

Since the discovery of angiogenesis and its relevance to the tumorigenesis of gynecologic malignancies, a number of therapeutic agents have been developed over the last decade, some of which have become standard treatments in combination with other therapies. Limited clinical activity has been demonstrated with anti-angiogenic monotherapies, and ongoing trials are focused on combination strategies with cytotoxic agents, immunotherapies and other targeted treatments. This article reviews the science behind angiogenesis within the context of gynecologic cancers, the evidence supporting the targeting of these pathways and future directions in clinical trials.

Diagnostic and Therapeutic Values of Angiogenic Factors in Endometrial Cancer

Endometrial cancer (EC) is the most frequent gynecological malignancy in developed countries and requires a relatively invasive diagnostic evaluation and operative therapy as the primary therapeutic approach. Angiogenesis is one of the main processes needed for cancer growth and spread. The production of angiogenic factors (AFs) appears early in the process of carcinogenesis. The detection of AFs in plasma and tissue and a better understanding of the angiogenic properties of EC may contribute not only to earlier but also more specific diagnosis and consequently tailored and individual therapeutic approaches. AFs and their receptors also have high potential as binding sites for targeted cancer therapy. In this review, we discuss angiogenesis in EC and the characteristics of the AFs that most contribute to angiogenesis in EC. We also highlight therapeutic strategies that target angiogenesis as potential EC therapy.

lncRNA-ZFAS1 promotes the progression of endometrial carcinoma by targeting miR-34b to regulate VEGFA expression

Zinc finger nuclear transcription factor, X-box binding 1-type containing 1 antisense RNA 1 (ZFAS1) functions as an oncogenic long noncoding RNA (lncRNA) to promote proliferation and metastasis of endometrial carcinoma cell; however, the underlying mechanism has not been fully understood. First, RT-qPCR analysis of endometrial carcinoma tissues and cells showed that ZFAS1 was enriched in endometrial carcinoma tissues and cells. miR-34b was reduced in endometrial carcinoma and suggested negative correlation with ZFAS1 in endometrial carcinoma. Second, functional assays demonstrated that siRNA-mediated silence of ZFAS1 suppressed endometrial carcinoma cell proliferation and metastasis. Third, ZFAS1 bind to miR-34b and negatively regulate expression of miR-34b in endometrial carcinoma cells. miR-34b also bind to and negatively regulate expression of vascular endothelial growth factor A (VEGFA) in endometrial carcinoma cells. Lastly, knockdown of miR-34b counteracted with the suppressive effects of ZFAS1 silence on endometrial carcinoma cell proliferation and metastasis. In conclusion, lncRNA ZFAS1 functioned as an oncogene to promote endometrial carcinoma cell proliferation and metastasis through miR-34b/VEGFA axis.

LINC00470 Stimulates Methylation of PTEN to Facilitate the Progression of Endometrial Cancer by Recruiting DNMT3a Through MYC

OBJECTIVES

Increasing researches emphasize the importance of long non-coding RNAs (lncRNAs) in the development of endometrial cancer (EC). There is wide recognition that LINC00470 is a critical participant in the tumorigenesis of cancers such as gastric cancer and glioblastoma, but its possible effects on EC progression remain to be explored.

METHODS

We collected EC tissues and cells, where the expression of LINC00470 was determined, and followed by the Kaplan-Meier analysis of EC patient survival. We next examined the effect of LINC00470 and phosphatase and tensin homolog (PTEN) on EC cell migration, invasion, tube formation in vitro, and angiogenesis in mice xenografted with tumor after gain- or loss-of-function treatments. RNA pull-down, Co-IP, and ChIP experiments were performed to analyze the targeting relationships among LINC00470, MYC and DNMT3a.

RESULTS

LINC00470 was aberrantly upregulated in EC and its high expression correlated to prognosis of EC patients. LINC00470 promoted invasiveness, migration, and angiogenesis of EC cells, and facilitated tumorigenesis and metastasis in vivo, but those effects were reversed by up-regulating PTEN. Functionally, LINC00470 bound to MYC in EC and that LINC00470 stimulated the binding of MYC to DNMT3a, and thus recruited DNMT3a through MYC to promote PTEN methylation.

CONCLUSIONS

Our findings revealed that LINC00470 stimulated PTEN methylation to inhibit its expression by MYC-induced recruitment of DNMT3a, thus aggravating EC.

Adjuvant effects of chemotherapeutics and Metformin on MFE-319 endometrial carcinoma cell line

We aimed to investigate the cytotoxicity of Metformin, Cisplatin, and Paclitaxel on MFE-319 endometrial carcinoma cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and immunocytochemistry assays. Half maximal inhibitory concentration (IC₅₀) doses of three drugs alone and in the dual combinations were applied to the cells. Immunocytochemical method was performed for the cell survival and for phosphatidylinositol 3-kinase (PI3K), phosphorylated extracellular regulated kinases (pErk)-1/2, Akt-1, phosphorylated Akt (pAkt)-1/2/3 cell growth markers and angiogenic vascular endothelial growth factor (VEGF). Immunoreactivities were evaluated using H-score and analyzed using the one-way analysis of variance (ANOVA) test for statistics. It was found that these drugs caused a decrease in the immunoreactivities of these markers. Particularly, dual combination of Paclitaxel and Cisplatin decreased the immunoreactivities of PI3K, pErk-1/2, Akt-1, and pAkt-1/2/3. Cisplatin and Paclitaxel were more effective than Metformin; on the other hand, Metformin has been shown to enhance the efficacy of these two drugs. In vitro or in vivo further studies are needed to investigate the efficacy of these three drugs via PI3K/Akt signal pathway.

Tie-2, G-CSF, and Leptin as Promising Diagnostic Biomarkers for Endometrial Cancer: A Pilot Study

Preoperative determination of the extent of endometrial cancer (EC) would avoid the complications associated with radical surgery. Screening of patients' plasma biomarkers might enable a more precise diagnosis of EC and a tailored treatment approach. This prospective case-control monocentric pilot study included 76 postmenopausal women (38 endometrioid EC patients and 38 control patients with benign gynecological conditions), and 37 angiogenic factors (AFs) were investigated as potential biomarkers for EC. AF concentrations in preoperative plasma samples were measured using Luminex xMAP™ multiplexing technology. The plasma levels of sTie-2 and G-CSF were significantly lower in EC compared to control patients, whereas the plasma levels of leptin were significantly higher in EC patients. Neuropilin-1 plasma levels were significantly higher in patients with type 2 EC (grade 3) compared to patients with lower grade cancer or controls. Follistatin levels were significantly higher in patients with lymphovascular invasion, and IL-8 plasma levels were significantly higher in patients with metastases. If validated, the plasma concentrations of the indicated AFs could represent an important additional diagnostic tool for the early detection and characterization of EC. This could guide the decision-making on the extent of surgery. Further studies with larger patient numbers are currently ongoing.

Tumor budding index and microvessel density assessment in patients with endometrial cancer: A pilot study

The present study aimed to analyze the association between tumor budding index (TBI) and microvessel density (MVD) and selected clinicopathological features in female patients with endometrial cancer (EC). The present study included 137 patients, of whom 117 had endometrial endometrioid cancer and 3 had non-endometrioid EC (NEEC). Additionally, 8 cases of simple endometrial hyperplasia and 9 cases of atypical endometrial hyperplasia were included in the present study. Patient age, menopausal status, tumor histological type, grade and International Federation of Gynecologists and Obstetricians (FIGO) clinical stage were investigated. Immunohistochemistry was utilized to detect MVD using a CD34 antibody, and a laminin-5γ2 antibody was used for TBI assessment. In nonmalignant endometrial lesions, the TBI was significantly lower than that in patients with EC and NEEC (P=0.002). Significant differences in median TBI (MD-TBI) were also observed between patients with low-grade EC (MD-TBI, 4.5) and high-grade EC (MD-TBI, 16.2; P=0.01). Age, body mass index and tumor FIGO stage were not indicated to be associated with the MD-TBI. Premenopausal patients with EC had lower MD-TBI values than postmenopausal patients (0.3 vs. 11.1; P<0.005). The median MVD-CD34 in the study group was 19 (range, 13–29). Significant differences in MVD-CD34 were observed between malignant and nonmalignant endometrial lesions (P=0.01). Histological grade was markedly associated with tumor MVD-CD34 (P=0.001). The MVD was higher in high-grade cancer (G3; MVD-CD34, 24.9) than in grade G1 and G2 lesions (MVD-CD34, 14 and 18.6, respectively; P=0.01). FIGO clinical stage was not associated with MVD-CD34 in low and high stage lesions (MD, 18.4 for FIGO stage I/II; MD, 17.6 for FIGO stage III/IV; P=0.2). High MVD was markedly associated with high MD-TBI (P=0.0002). In conclusion, TBI could be a valuable indicator of tumor aggressiveness in patients with EC. The presence of the tumor budding phenomenon with increased MVD may have the potential to further refine clinical management decisions when endometrial malignancy is detected.

Sulfated glycolipid PG545 induces endoplasmic reticulum stress and augments autophagic flux by enhancing anticancer chemotherapy efficacy in endometrial cancer

The sulfated glycolipid PG545 shows promising antitumor activity in various cancers. This study was conducted to explore the effects and the mechanism of PG545 action in endometrial cancer (EC). PG545 exhibited strong synergy as assessed by the Chou-Talalay-Method in vitro when combined with cisplatin, or paclitaxel in both type I (Hec1B) and type II (ARK2) EC cell lines. While PG545 showed antitumor activity as monotherapy, a combination of PG545 with paclitaxel and cisplatin was highly effective in reducing the tumor burden and significantly prolonged survival of both Hec1B and ARK2 xenograft bearing mice. Mechanistically, PG545 elicits ER stress as an early response with resultant induction of autophagy. Our data demonstrated an increase in pERK, Bip/Grp78, IRE1α, Calnexin and CHOP/GADD153 within 6-24 hrs of PG545 treatment in EC cells. In parallel, PG545 also blocked FGF2 and HB-EGF mediated signaling in EC cells. Moreover, melatonin-mediated ER stress inhibition reduced PG545-mediated autophagy and PG545 in combination with cisplatin further heightened this stress response. Collectively these data indicate that PG545 exhibits strong synergistic effects with chemotherapeutics in vitro and showed promising antitumor activity in vivo. Our preclinical data indicates that in future studies PG545 can be a useful adjunct to chemotherapy in endometrial cancer.

Multi-omics profiling reveals distinct microenvironment characterization of endometrial cancer

Endometrial cancer is a heterogeneous disease with distinct molecular characteristics, however, the current clinical trials in immunotherapies have reported only a 13% response rate in endometrial cancer. In this study, we aim to estimate the relative abundance of immune cells infiltrating into the tumor tissues. The samples were clustered based on the immune cell abundance. Most of cluster-specifically mutated genes were detected in clusters I and II, while the copy number alterations were specifically detected in cluster III. Overrepresentation enrichment analysis (ORA) of the genes specifically upregulated in a specific cluster revealed that the immune-related pathways were enriched by the genes in cluster I. Moreover, immune checkpoint proteins and immune co-stimulators were also observed to be highly expressed in cluster I. In addition, we also built a multivariable Cox regression model based on the immune checkpoint genes and co-stimulators. The high-risk and low-risk groups stratified by the risk scores of the Cox model exhibited significant prognostic difference in both training and validation datasets. In summary, the systematic analysis greatly improves our understanding of the immunophenotype of endometrial cancer and its association with biomarkers and prognosis.

Epithelial to Mesenchymal Transition and Cell Biology of Molecular Regulation in Endometrial Carcinogenesis

Endometrial carcinogenesis is involved in several signaling pathways and it comprises multiple steps. The four major signaling pathways-PI3K/AKT, Ras/Raf/MEK/ERK, WNT/β-catenin, and vascular endothelial growth factor (VEGF)-are involved in tumor cell metabolism, growth, proliferation, survival, and angiogenesis. The genetic mutation and germline mitochondrial DNA mutations also impair cell proliferation, anti-apoptosis signaling, and epithelial⁻mesenchymal transition by several transcription factors, leading to endometrial carcinogenesis and distant metastasis. The PI3K/AKT pathway activates the ransforming growth factor beta (TGF-β)-mediated endothelial-to-mesenchymal transition (EMT) and it interacts with downstream signals to upregulate EMT-associated factors. Estrogen and progesterone signaling in EMT also play key roles in the prognosis of endometrial carcinogenesis. In this review article, we summarize the current clinical and basic research efforts regarding the detailed molecular regulation in endometrial carcinogenesis, especially in EMT, to provide novel targets for further anti-carcinogenesis treatment.

Combined silencing of VEGF-A and angiopoietin-2, a more effective way to inhibit the Ishikawa endometrial cancer cell line

BACKGROUND

Angiogenesis is critical for the growth and metastasis of solid tumors and is, therefore, an important therapeutic target. Despite the great research advances in tumor therapies targeting vascular endothelial growth factor (VEGF), drug resistance frequently occurs, and further strategies targeting the tumor vasculature are of primary concern.

PURPOSE

The present study aimed to determine whether a combination of small interfering RNAs (siRNAs) targeting VEGF-A and angiopoietin-2 (Ang-2) inhibited the biologic mechanisms of endometrial cancer more effectively compared to either one alone, in vitro and in vivo.

METHODS

VEGF-A and Ang-2 were silenced by siRNA in Ishikawa endometrial cancer cells. Cell growth, apoptosis, metastasis, and tumor angiogenesis were measured in vitro and in vivo.

RESULTS

There was no difference observed in cell apoptosis rate; however, combined silencing of VEGF-A and Ang-2 resulted in a stronger inhibition of cell proliferation and invasion (P<0.05). Similarly, a greater reduction of tumor size and angiogenesis was seen with the concurrent administration of siRNAs targeting VEGF-A and Ang-2 in nude mice (P<0.05).

CONCLUSION

Our data indicated that simultaneous blockade of VEGF-A and Ang-2 may serve as a novel and effective therapeutic strategy in endometrial cancer.

Linking obesity-induced leptin-signaling pathways to common endocrine-related cancers in women

Obesity is related to many major diseases and cancers. Women have higher rates of obesity and obesity is linked to commonly occurring cancers in women. However, there is a lack of knowledge of the unique mechanism(s) involved in each type of cancer. The objective of this review is to highlight the need for novel experimental approaches and a better understanding of the common and unique pathways to resolve controversies regarding the role of obesity in cancer. In women, there is a link between hormones and obesity-associated genes in cancer development. Leptin is an obesity-associated gene that has been studied extensively in cancers; however, whether the defect is in the leptin gene or in its signaling pathways remains unclear. Both leptin and its receptor have been positively correlated with cancer progression in some endocrine-related cancers in women. This review offers an up-to-date and cohesive review of both upstream and downstream pathways of leptin signaling in cancer and a comprehensive picture of cancer pathogenesis in light of current evidence of leptin effects in several major types of cancer. This work is intended to aid in the design of better therapeutic strategies for obese/overweight women with cancer.

Synthesis, Structural Characterization, and Antiangiogenic Activity of Polyfluorinated Benzamides

The introduction of fluorine into bioactive molecules is a matter of importance in medicinal chemistry. In this study, representatives of various chemical entities of fluoroaromatic compounds were synthesized. Depending on the reaction conditions, either tetrafluorophthalimides or ammonium tetrafluorophthalamates are accessible from tetrafluorophthalic anhydride and primary amines. Tetrafluorophthalamic acids undergo thermal decarboxylation to yield tetrafluorobenzamides. These could be successfully converted upon treatment with primary amines, in the course of an aromatic nucleophilic substitution, to 2,3,5-trifluorobenzamides with respective amino substituents at the 4-position. The five structure types were characterized by means of spectroscopic and crystallographic methods. The synthesized compounds were evaluated as inhibitors of angiogenesis by measuring microvessel outgrowth in a rat aortic ring assay. The biological activity was maintained throughout these different polyfluorinated chemotypes.

New therapies for advanced, recurrent, and metastatic endometrial cancers

Endometrial cancer is the most common gynecologic malignancy in the United States, accounting for 6% of cancers in women. In 2017, an estimated 61,380 women were diagnosed with endometrial cancer, and approximately 11,000 died from this disease. From 1987 to 2008, there was a 50% increase in the incidence of endometrial cancer, with an approximate 300% increase in the number of associated deaths. Although there are many chemotherapeutic and targeted therapy agents approved for ovarian, fallopian tube and primary peritoneal cancers, since the 1971 approval of megestrol acetate for the palliative treatment of advanced endometrial cancer, only pembrolizumab has been Food and Drug Administration (FDA)-approved for high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) endometrial cancer; this highlights the need for new therapies to treat advanced, recurrent, metastatic endometrial cancer. In this review, we discuss current and emerging treatment options for endometrial cancer, including chemotherapy, targeted therapy, and immunotherapy. The National Cancer Institute (NCI) and others are now focusing their efforts on the design of scientifically rational targeted therapy and immunotherapy trials for specific molecular phenotypes of endometrial cancer. This is essential for the advancement of cancer care for women, which is threatened by a severe enrollment decline of approximately 80% for gynecologic oncology clinical trials.

A prodrug of green tea polyphenol (-)-epigallocatechin-3-gallate (Pro-EGCG) serves as a novel angiogenesis inhibitor in endometrial cancer

Anti-angiogenesis effect of a prodrug of green tea polyphenol (-)-epigallocatechin-3-gallate (Pro-EGCG) in malignant tumors is not well studied. Here, we investigated how the treatment with Pro-EGCG inhibited tumor angiogenesis in endometrial cancer. Tumor xenografts of human endometrial cancer were established and subjected to microarray analysis after Pro-EGCG treatment. First, we showed Pro-EGCG inhibited tumor angiogenesis in xenograft models through down-regulation of vascular endothelial growth factor A (VEGFA) and hypoxia inducible factor 1 alpha (HIF1α) in tumor cells and chemokine (C-X-C motif) ligand 12 (CXCL12) in host stroma by immunohistochemical staining. Next, we investigated how HIF1α/VEGFA was down-regulated and how the reduction of CXCL12 inhibited tumor angiogenesis. We found that VEGFA secretion from endometrial cancer cells was decreased by Pro-EGCG treatment through inhibiting PI3K/AKT/mTOR/HIF1α pathway. Furthermore, the down-regulation of CXCL12 in stromal cells by Pro-EGCG treatment restricted migration and differentiation of macrophages thereby inhibited infiltration of VEGFA-expressing tumor-associated macrophages (TAMs). Taken together, we demonstrated that treatment with Pro-EGCG not only decreases cancer cell-secreted VEGFA but also inhibits TAM-secreted VEGFA in endometrial cancer. These findings demonstrate that Pro-EGCG is a novel angiogenesis inhibitor for endometrial cancer.

Recent Advances in Endometrial Cancer

Endometrial cancer is the most common gynecologic malignancy in the United States, with yearly rates continuing to increase. Most women present with early stage disease; however, advanced disease carries a grave prognosis. As a result, novel therapies are currently under investigation for the treatment of endometrial cancer. These advances include a better understanding of the genetic basis surrounding the development of endometrial cancer, novel surgical therapies, and new molecular targets for the treatment of this disease. This review explores the literature regarding these advancements in endometrial cancer.

Polyphenol-based nutraceuticals for the control of angiogenesis: Analysis of the critical issues for human use

Angiogenesis, the formation of new blood-vessel, is crucial in the pathogenesis of several diseases, and thus represents a druggable target for the prevention and treatment of different disorders. It is nowadays well kwon how diet can control cancer development and progression, and how the use of certain diet components can prevent cancer development. Several studies, also from our lab, now indicate that natural plant products including nutraceuticals modulate tumor angiogenesis. In this review, it is reported how phytochemicals, comprising hydroxytyrosol, resveratrol, genistein, curcumin, and the green tea component epigallocatechin-3-gallate among the others, negatively regulate angiogenesis. A single plant-derived compound may affect both endothelial and tumor cells, with the common denominator of anti-inflammatory and radical scavenger activities. Beside these positive features, documented in cellular and animal models, a series of critical issues should be considered from a pharmacological point of view as: what is the best source of bioactive compounds: food and beverages, extracted phytocomplexes, isolated nutraceuticals or synthetic analogues? How is the bioavailability of the compounds of interest in relation to the above source? Is there any biological activity by circulating metabolic derivatives? What is the best formulation, administration route and posology? How safe are in humans? How strong and reliable are the clinical trials designed for their use alone or in combination with conventional chemotherapy? After a dissertation of these critical points, the conclusion can be drawn that novel and effective strategies should be optimized to improve their bioavailability and efficacy, considering their exploitation as chemopreventive and/or curative approaches.