Tissue factor expression in ovarian cancer: implications for immunotherapy with hI-con1, a factor VII-IgGF(c) chimeric protein targeting tissue factor

Preclinical Characterization of XB002, an Anti-Tissue Factor Antibody-Drug Conjugate for the Treatment of Solid Tumors

Tissue factor (TF) is overexpressed in various cancers and is typically associated with poor clinical outcomes. XB002 is an anti-TF antibody-drug conjugate designed to selectively deliver a cytotoxic payload to TF-expressing tumors while minimizing TF-related adverse events, particularly bleeding. The conjugate consists of a zovodotin linker-payload attached to a mAb (clone 25A3) that binds TF with high affinity (KD = 0.86 nmol/L). In vitro coagulation assays confirmed that 25A3 does not interfere with the clotting cascade; even at a concentration of 100 nmol/L, it did not affect the activation of coagulation factor X or thrombin generation. XB002 demonstrated efficient internalization in TF-expressing cancer cell lines, exhibiting potent cytotoxicity at subnanomolar concentrations. In the HPAF-II xenograft model, a regimen of XB002 (1.5 mg/kg, i.v.) administered once weekly for two weeks achieved complete tumor regression, with no detectable tumor growth up to five weeks after the second dose. In murine patient-derived xenograft models, a single dose of XB002 (10 mg/kg, i.v.) inhibited tumor growth across multiple cancer models, including bladder, cervical, gastric, head and neck squamous cell carcinoma, and non-small cell lung cancers. Remarkably, complete tumor regression was observed in the cervical cancer and head and neck squamous cell carcinoma models within 30 days of treatment. In nonhuman primate studies, XB002 demonstrated favorable pharmacokinetics with exposure in the desired therapeutic range and no signs of bleeding or neutropenia. Collectively, these data highlight XB002's broad-spectrum antitumor activity and strongly support its further clinical development.

O-GlcNAcylation: Crosstalk between Hemostasis, Inflammation, and Cancer

O-linked β-N-acetylglucosamine (O-GlcNAc, O-GlcNAcylation) is a post-translational modification of serine/threonine residues of proteins. Alterations in O-GlcNAcylation have been implicated in several types of cancer, regulation of tumor progression, inflammation, and thrombosis through its interaction with signaling pathways. We aim to explore the relationship between O-GlcNAcylation and hemostasis, inflammation, and cancer, which could serve as potential prognostic tools or clinical predictions for cancer patients' healthcare and as an approach to combat cancer. We found that cancer is characterized by high glucose demand and consumption, a chronic inflammatory state, a state of hypercoagulability, and platelet hyperaggregability that favors thrombosis; the latter is a major cause of death in these patients. Furthermore, we review transcription factors and pathways associated with O-GlcNAcylation, thrombosis, inflammation, and cancer, such as the PI3K/Akt/c-Myc pathway, the nuclear factor kappa B pathway, and the PI3K/AKT/mTOR pathway. We also review infectious agents associated with cancer and chronic inflammation and potential inhibitors of cancer cell development. We conclude that it is necessary to approach both the diagnosis and treatment of cancer as a network in which multiple signaling pathways are integrated, and to search for a combination of potential drugs that regulate this signaling network.

Tisotumab Vedotin as Second- or Third-Line Therapy for Recurrent Cervical Cancer

BACKGROUND

Recurrent cervical cancer is a life-threatening disease, with limited treatment options available when disease progression occurs after first-line combination therapy.

METHODS

We conducted a phase 3, multinational, open-label trial of tisotumab vedotin as second- or third-line therapy in patients with recurrent or metastatic cervical cancer. Patients were randomly assigned, in a 1:1 ratio, to receive tisotumab vedotin monotherapy (2.0 mg per kilogram of body weight every 3 weeks) or the investigator's choice of chemotherapy (topotecan, vinorelbine, gemcitabine, irinotecan, or pemetrexed). The primary end point was overall survival.

RESULTS

A total of 502 patients underwent randomization (253 were assigned to the tisotumab vedotin group and 249 to the chemotherapy group); the groups were similar with respect to demographic and disease characteristics. The median overall survival was significantly longer in the tisotumab vedotin group than in the chemotherapy group (11.5 months [95% confidence interval {CI}, 9.8 to 14.9] vs. 9.5 months [95% CI, 7.9 to 10.7]), results that represented a 30% lower risk of death with tisotumab vedotin than with chemotherapy (hazard ratio, 0.70; 95% CI, 0.54 to 0.89; two-sided P = 0.004). The median progression-free survival was 4.2 months (95% CI, 4.0 to 4.4) with tisotumab vedotin and 2.9 months (95% CI, 2.6 to 3.1) with chemotherapy (hazard ratio, 0.67; 95% CI, 0.54 to 0.82; two-sided P<0.001). The confirmed objective response rate was 17.8% in the tisotumab vedotin group and 5.2% in the chemotherapy group (odds ratio, 4.0; 95% CI, 2.1 to 7.6; two-sided P<0.001). A total of 98.4% of patients in the tisotumab vedotin group and 99.2% in the chemotherapy group had at least one adverse event that occurred during the treatment period (defined as the period from day 1 of dose 1 until 30 days after the last dose); grade 3 or greater events occurred in 52.0% and 62.3%, respectively. A total of 14.8% of patients stopped tisotumab vedotin treatment because of toxic effects.

CONCLUSIONS

In patients with recurrent cervical cancer, second- or third-line treatment with tisotumab vedotin resulted in significantly greater efficacy than chemotherapy. (Funded by Genmab and Seagen [acquired by Pfizer]; innovaTV 301 ClinicalTrials.gov number, NCT04697628.).

Identification of chemoresistance associated key genes-miRNAs-TFs in docetaxel resistant breast cancer by bioinformatics analysis

The present study aimed to identify the differentially expressed genes (DEGs) and enriched pathways in docetaxel (DTX) resistant breast cancer cell lines by bioinformatics analysis. The microarray dataset GSE28784 was obtained from gene expression omnibus (GEO) database. The differentially expressed genes (DEGs), gene ontology (GO), and Kyoto Encyclopedia of gene and genome (KEGG) pathway analyses were performed with the help of GEO2R and DAVID tools. Furthermore, the protein-protein interaction (PPI) and hub-gene network of DEGs were constructed using STRING and Cytohubba tools. The prognostic values of hub genes were calculated with the help of the Kaplan-Meier plotter database. From the GEO2R analysis, 222 DEGs were identified of which 120 are upregulated and 102 are downregulated genes. In the PPIs network, five up-regulated genes including CCL2, SPARC, CYR61, F3, and MFGE8 were identified as hub genes. It was observed that low expression of six hub genes CXCL8, CYR61, F3, ICAM1, PLAT, and THBD were significantly correlated with poor overall survival of BC patients in survival analysis. miRNA analysis identified that hsa-mir-16-5p, hsa-mir-335-5p, hsa-mir-124-3p, hsa-mir-20a-5p, and hsa-mir-155-5p are the top 5 interactive miRNAs that are commonly interacting with more hub genes with degree score of greater than five. Additionally, drug-gene interaction analysis was performed to identify drugs which are could potentially elevate/lower the expression levels of hub genes. In summary, the gene-miRNAs-TFs network and subsequent correlation of candidate drugs with hub genes may improve individualized diagnosis and help select appropriate combination therapy for DTX-resistant BC in the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03971-2.

Treatment of Ovarian Cancer Beyond PARP Inhibition: Current and Future Options

Ovarian cancer is the leading cause of gynecological cancer death. Improved understanding of the biologic pathways and introduction of poly (ADP-ribose) polymerase inhibitors (PARPi) during the last decade have changed the treatment landscape. This has improved outcomes, but unfortunately half the women with ovarian cancer still succumb to the disease within 5 years of diagnosis. Pathways of resistance to PARPi and chemotherapy have been studied extensively, but there is an unmet need to overcome treatment failure and improve outcome. Major mechanisms of PARPi resistance include restoration of homologous recombination repair activity, alteration of PARP function, stabilization of the replication fork, drug efflux, and activation of alternate pathways. These resistant mechanisms can be targeted to sensitize the resistant ovarian cancer cells either by rechallenging with PARPi, overcoming resistance mechanism or bypassing resistance pathways. Augmenting the PARPi activity by combining it with other targets in the DNA damage response pathway, antiangiogenic agents and immune checkpoint inhibitors can potentially overcome the resistance mechanisms. Methods to bypass resistance include targeting non-cross-resistant pathways acting independent of homologous recombination repair (HRR), modulating tumour microenvironment, and enhancing drug delivery systems such as antibody drug conjugates. In this review, we will discuss the first-line management of ovarian cancer, resistance mechanisms and potential strategies to overcome these.

Clear cell carcinoma of the ovary and venous thromboembolism: a systematic review and meta-analysis

OBJECTIVES

As the second most common subtype of Epithelial ovarian cancers (EOCs), ovarian clear cell carcinoma (OCCC) is associated with a high rate of cancer-associated thrombosis. Previous studies revealed the wide range prevalence (6-42%) of venous thromboembolism (VTE) among OCCC patients. This study aimed to determine the prevalence of VTE among OCCC patients as well as factors affecting it.

METHODS

PubMed, Scopus, Embase, and Cochrane Library databases were searched up to December 12th, 2022. Studies reporting venous thromboembolic events in women with clear cell carcinoma of the ovary were included. Demographic data, clinical, and paraclinical features of the patients were independently extracted by two reviewers.

RESULTS

Out of the 2254 records, 43 studies were processed for final review. The qualified studies involved 573 VTE cases among 2965 patients with OCCC. The pooled prevalence of VTE among OCCC patients was 21.32% (95%CI=(17.38-25.87)). Most VTE events were reported in Japanese women (26.15%), followed by Americans (24.41%) and UK (21.57%), and Chinese (13.61%) women. VTE was more common in patients with advanced stages (37.79%) compared to those with early stages of the disease (16.54%).

CONCLUSIONS

Ovarian clear cell carcinoma is associated with a high rate of cancer-associated thrombosis. VTE events in OCCC patients were higher in advanced stages and Japanese women.

Tissue factor as a novel diagnostic target for early detection of ovarian cancer using ultrasound microbubbles

INTRODUCTION

Ovarian cancer (OC) is the deadliest gynecologic malignancy, with an overall 5-year survival rate of less than 30%. The existing paradigm for OC detection involves a serum marker, CA125, and ultrasound examination, neither of which is sufficiently specific for OC. This study addresses this deficiency through the use of a targeted ultrasound microbubble directed against tissue factor (TF).

METHODS

TF expression was examined in both OC cell lines and patient-derived tumor samples via western blotting and IHC. In vivo microbubble ultrasound imaging was analyzed using high grade serous ovarian carcinoma orthotopic mouse models.

RESULTS

While TF expression has previously been described on angiogenic, tumor-associated vascular endothelial cells (VECs) of several tumor types, this is first study to show TF expression on both murine and patient-derived ovarian tumor-associated VECs. Biotinylated anti-TF antibody was conjugated to streptavidin-coated microbubbles and in vitro binding assays were performed to assess the binding efficacy of these agents. TF-targeted microbubbles successfully bound to TF-expressing OC cells, as well as an in vitro model of angiogenic endothelium. In vivo, these microbubbles bound to the tumor-associated VECs of a clinically relevant orthotopic OC mouse model.

CONCLUSION

Development of a TF-targeted microbubble capable of successfully detecting ovarian tumor neovasculature could have significant implications towards increasing the number of early-stage OC diagnoses. This preclinical study shows potential for translation to clinical use, which could ultimately help increase the number of early OC detections and decrease the mortality associated with this disease.

Systematic study of tissue factor expression in solid tumors

BACKGROUND

Elevated tissue factor (TF) expression, although restricted in normal tissue, has been reported in multiple solid cancers, and expression has been associated with poor prognosis. This manuscript compares TF expression across various solid tumor types via immunohistochemistry in a single study, which has not been performed previously.

AIMS

To increase insight in the prevalence and cellular localization of TF expression across solid cancer types, we performed a detailed and systematic analysis of TF expression in tumor tissue obtained from patients with ovarian, esophageal, bladder, cervical, endometrial, pancreatic, prostate, colon, breast, non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), and glioblastoma. The spatial and temporal variation of TF expression was analyzed over time and upon disease progression in patient-matched biopsies taken at different timepoints. In addition, TF expression in patient-matched primary tumor and metastatic lesions was also analyzed.

METHODS AND RESULTS

TF expression was detected via immunohistochemistry (IHC) using a validated TF-specific antibody. TF was expressed in all cancer types tested, with highest prevalence in pancreatic cancer, cervical cancer, colon cancer, glioblastoma, HNSCC, and NSCLC, and lowest in breast cancer. Staining was predominantly membranous in pancreatic, cervical, and HNSCC, and cytoplasmic in glioblastoma and bladder cancer. In general, expression was consistent between biopsies obtained from the same patient over time, although variability was observed for individual patients. NSCLC biopsies of primary tumor and matched lymph node metastases showed no clear difference in TF expression overall, although individual patient changes were observed.

CONCLUSION

This study shows that TF is expressed across a broad range of solid cancer types, and expression is present upon tumor dissemination and over the course of treatment.

Recent Advancement in Anticancer Compounds from Marine Organisms: Approval, Use and Bioinformatic Approaches to Predict New Targets

In recent years, the study of anticancer bioactive compounds from marine sources has received wide interest. Contextually, world regulatory authorities have approved several marine molecules, and new synthetic derivatives have also been synthesized and structurally improved for the treatment of numerous forms of cancer. However, the administration of drugs in cancer patients requires careful evaluation since their interaction with individual biological macromolecules, such as proteins or nucleic acids, determines variable downstream effects. This is reflected in a constant search for personalized therapies that lay the foundations of modern medicine. The new knowledge acquired on cancer mechanisms has certainly allowed advancements in tumor prevention, but unfortunately, due to the huge complexity and heterogeneity of cancer, we are still looking for a definitive therapy and clinical approaches. In this review, we discuss the significance of recently approved molecules originating from the marine environment, starting from their organism of origin to their structure and mechanism of action. Subsequently, these bio-compounds are used as models to illustrate possible bioinformatics approaches for the search of new targets that are useful for improving the knowledge on anticancer therapies.

Selective delivery of clinically approved tubulin binding agents through covalent conjugation to an active targeting moiety

Abstract:

The efficacy and tolerability of tubulin binding agents are hampered by their low specificity for cancer cells, like most clinically used anticancer agents. To improve specificity, tubulin binding agents have been covalently conjugated to agents which target cancer cells to give actively targeted drug conjugates. These conjugates are designed to increase uptake of the drug by cancer cells, while having limited uptake by normal cells thereby improving efficacy and tolerability. Approaches used include attachment to small molecules, polysaccharides, peptides, proteins and antibodies that exploit the overexpression of receptors for these substances. Antibody targeted strategies have been the most successful to date with six such examples having gained clinical approval. Many other conjugate types, especially those targeting the folate receptor, have shown promising efficacy and toxicity profiles in pre-clinical models and in early-stage clinical studies. Presented herein is a discussion of the success or otherwise of the recent strategies used to form these actively targeted conjugates.

Revisiting antibody-drug conjugates and their predictive biomarkers in platinum-resistant ovarian cancer

Until to date, platinum derived drugs are still the backbone of treating ovarian cancer (OC). Most patients treated with platinum-based chemotherapy develop resistance during the course of their management. The treatment of platinum-resistant ovarian cancer (PROC) is challenging. Few therapeutic options are available for patients with this aggressive disease. Besides, there are liminal advances regarding new anticancer drugs as well as validated predictive biomarkers of clinical outcomes in this setting. The enrollment of PROC patients in interventional studies is limited as compared to newly launched clinical trials for platinum-sensitive OC. Enthusiastically, the emergence of antibody-drug conjugates (ADCs) has provided promising findings for further clinical development in PROC. ADCs have the advantage to selectively deliver cytotoxic drugs to cancer cells expressing several of antigens using specific monoclonal antibodies based on the concept of immune bioconjugation. This innovative class of therapeutics showed encouraging early signs of clinical efficacy in PROC particularly mirvetuximab soravtansine that has been successfully introduced into three randomized and controlled phase III studies. In this review, the evidence from clinical trials supporting the development of ADCs targeting folate receptor alpha, sodium-dependent phosphate transporter 2B, dipeptidase 3, mesothelin, mucin 16, and tissue factor using various cytotoxic payloads in PROC is reviewed.

Antibody-Drug Conjugates: A Promising Novel Therapy for the Treatment of Ovarian Cancer

Antibody-drug conjugates (ADCs) represent a novel and promising therapeutic strategy for the treatment of cancer patients. ADCs target antigens highly expressed on the membrane surface of tumor cells to selectively deliver a cytotoxic drug. Ovarian tumors differentially express tumor-specific antigens, which can be used to guide ADCs. This strategy allows for optimizing tumor targeting while minimizing systemic toxicity compared to classical chemotherapeutic agents. ADCs can be improved by using a cleavable linker allowing the delivery of the toxic payload in surrounding cells not expressing the target protein, therefore acting on heterogeneous tumors with different cell populations. Currently, more than 15 ADCs are under preclinical investigation in ovarian cancer, and some of them have already been tested in early-phase clinical trials with promising results. In this review, we summarize the mechanism of action and the toxicity profile of ADCs and discuss the latest preclinical discoveries and forthcoming applications in ovarian cancer.

Antibody-drug conjugates for the treatment of ovarian cancer

INTRODUCTION

Ovarian cancer typically presents at an advanced stage and while initial chemotherapy response rates are favorable, a majority of patients experience recurrence with the subsequent development of chemoresistance. Recurrent, platinum-resistant disease is associated with a very poor prognosis as treatment in this setting is often limited by systemic toxicity. Antibody-drug conjugates (ADCs) are novel therapeutic agents designed to target antigens specific to ovarian tumor cells with direct delivery of cytotoxic agents to combat recurrent, platinum-resistant disease while limiting systemic toxicity.

AREAS COVERED

The basic structure and function of ADCs will be reviewed as well as the current data on ADCs under investigation in ovarian cancer.

EXPERT OPINION

ADCs represent a promising class of targeted therapy in recurrent ovarian cancer with excellent response rates particularly when utilized as combination therapy. While mirvetuximab soravtansine is the only ADC that has been evaluated in a phase 3 trial, many other ADCs and trials are on the horizon. As the field of targeted therapy continues to evolve, continued development of target antigens and ADCs are likely to represent a key development in treatment of recurrent, platinum-resistant disease.

Chimeric oncolytic Ad5/3 virus replicates and lyses ovarian cancer cells through desmoglein-2 cell entry receptor

Despite new therapies, the estimated 229 875 women living with ovarian cancer have a 5‐year survival rate of 47.6%. This cavity‐localized cancer lends itself to local administration of modalities, such as the oncolytic adenovirus (Ad) Ad5/3‐D24‐granulocyte‐macrophage colony‐stimulating factor virus (ONCOS‐102). Its repeated administration to a patient with chemotherapy‐refractory ovarian cancer induced CD8+ antitumor immune responses with the overall survival reaching 40 months. Here we probe the dominant receptor used by ONCOS‐102 in four established epithelial ovarian cancer cell lines. Ad3 can use the desmoglein‐2 (DSG2) and CD46 receptors on susceptible cells. DSG2 was nearly absent in A2780 cells but was expressed in more than 90% of OAW42, OVCAR3, and OV‐90 cells. After 96 hours, ONCOS‐102 treatment showed significant oncolytic activity (≧50%) in OAW42, OVCAR3, and OV‐90 cells, but minimal activity in A2780 cells, suggesting DSG2 as the dominant receptor for ONCOS‐102. Furthermore, retrospective analyses of phase I clinical trial of ONCOS‐102 treatment of 12 patients with varied tumors indicated a correlation between viral genomes in blood and DSG2 RNA expression. These data support the role of DSG2 expression on cancer cells in virus infectivity and the continued development of ONCOS‐102 for ovarian cancer treatment.

These data support the role of DSG2 expression on cancer cells in virus infectivity and the continued development of ONCOS‐102 for ovarian cancer treatment.

Tisotumab vedotin in patients with advanced or metastatic solid tumours (InnovaTV 201): a first-in-human, multicentre, phase 1-2 trial

BACKGROUND

Tisotumab vedotin is a first-in-human antibody-drug conjugate directed against tissue factor, which is expressed across multiple solid tumour types and is associated with poor clinical outcomes. We aimed to establish the safety, tolerability, pharmacokinetic profile, and antitumour activity of tisotumab vedotin in a mixed population of patients with locally advanced or metastatic (or both) solid tumours known to express tissue factor.

METHODS

InnovaTV 201 is a phase 1-2, open-label, dose-escalation and dose-expansion study done at 21 centres in the USA and Europe. Patients (aged ≥18 years) had relapsed, advanced, or metastatic cancer of the ovary, cervix, endometrium, bladder, prostate, oesophagus, squamous cell carcinoma of the head and neck or non-small-cell lung cancer; an Eastern Cooperative Oncology Group performance status of 0-1; and had relapsed after or were not eligible to receive the available standard of care. No specific tissue factor expression level was required for inclusion. In the dose-escalation phase, patients were treated with tisotumab vedotin between 0·3 and 2·2 mg/kg intravenously once every 3 weeks in a traditional 3 + 3 design. In the dose-expansion phase, patients were treated at the recommended phase 2 dose. The primary endpoint was the incidence of adverse events, including serious adverse events, infusion-related, treatment-related and those of grade 3 or worse, and study drug-related adverse events, analysed in all patients who received at least one dose of tisotumab vedotin (full analysis population). This trial is registered with ClinicalTrials.gov, number NCT02001623, and is closed to new participants with follow-up ongoing.

FINDINGS

Between Dec 9, 2013, and May 18, 2015, 27 eligible patients were enrolled to the dose-escalation phase. Dose-limiting toxicities, including grade 3 type 2 diabetes mellitus, mucositis, and neutropenic fever, were seen at the 2·2 mg/kg dose; therefore, 2·0 mg/kg of tisotumab vedotin intravenously once every 3 weeks was established as the recommended phase 2 dose. Between Oct 8, 2015, and April 26, 2018, 147 eligible patients were enrolled to the dose-expansion phase. The most common (in ≥20% of patients) treatment-emergent adverse events of any grade were epistaxis (102 [69%] of 147 patients), fatigue (82 [56%]), nausea (77 [52%]), alopecia (64 [44%]), conjunctivitis (63 [43%]), decreased appetite (53 [36%]), constipation (52 [35%]), diarrhoea (44 [30%]), vomiting (42 [29%]), peripheral neuropathy (33 [22%]), dry eye (32 [22%]), and abdominal pain (30 [20%]). The most common adverse events of grade 3 or worse were fatigue (14 [10%] of 147 patients), anaemia (eight [5%]), abdominal pain (six [4%]), hypokalaemia (six [4%]), conjunctivitis (five [3%]), hyponatraemia (five [3%]), and vomiting (five [3%]). 67 (46%) of 147 patients had a treatment-emergent serious adverse event. 39 (27%) of 147 patients had a treatment-emergent serious adverse event related to the study drug. Infusion-related reactions occurred in 17 (12%) of 147 patients. Across tumour types, the confirmed proportion of patients who achieved an objective response was 15·6% (95% CI 10·2-22·5; 23 of 147 patients). There were nine deaths across all study phases (three in the dose-escalation phase and six in the dose-expansion phase); only one case of pneumonia in the dose-expansion phase was considered possibly related to study treatment.

INTERPRETATIONS

Tisotumab vedotin has a manageable safety profile with encouraging preliminary antitumour activity across multiple tumour types in heavily pretreated patients. Continued evaluation of tisotumab vedotin is warranted in solid tumours.

FUNDING

Genmab A/S.

Expression of tissue factor in human cervical carcinoma tissue

The present study aimed to investigate tissue factor (TF) expression in cervical cancer and explore its association with disease progression. A total of 258 cervical cancer tissues and their adjacent normal tissues were collected between September 2014 and September 2016. TF expression was detected in the tissue samples by immunohistochemistry and western blot analysis. Associations between the expression of TF and clinical stage, differentiation status and metastasis of cancer cells were examined. The mean immunohistochemistry score of TF expression in cervical cancer tissues was 2.86±1.76, which was significantly increased compared with the adjacent normal tissues (0.28±0.45). The expression of TF was also significantly associated with the clinical stage, lymph node metastasis and distant metastasis of cancer cells. Immunohistochemistry staining and western blot analysis demonstrated that TF expression in cervical cancer tissues significantly increased as the clinical stage increased. TF expression in tumor tissues from patients with lymph node metastasis was significantly increased compared with samples from patients without lymph node metastasis. TF expression was also significantly increased in patients with distant metastasis compared with those without. In conclusion, TF is highly expressed in cervical cancer tissues and high expression of TF may enhance the invasion and metastasis of cervical cancer cells.

Development of a radionuclide-labeled monoclonal anti-CD55 antibody with theranostic potential in pleural metastatic lung cancer

Decay-accelerating factor (CD55 or DAF) inhibits complement-dependent cytotoxicity. We determined that CD55 is overexpressed in 76.47% of human non-small cell lung cancer tissue specimens. We therefore developed a lutetium-177-labeled chimeric monoclonal antibody against CD55. CD55-specific single-chain variable fragment (scFv) was selected from a naïve chicken scFv phage-display library, converted to IgG, and radiolabeled with lutetium-177 to generate a ¹⁷⁷Lu-anti-CD55 antibody. We then charaterized the biodistribution of this antibody in a mouse model of pleural metastatic lung cancer. The ¹⁷⁷Lu-anti-CD55 antibody was primarily retained in tumor tissue rather than normal tissue. Treatment of the mice with ¹⁷⁷Lu-anti-CD55 reduced the growth of lung tumors and improved median survival in vivo by two-fold compared to controls. Finally, ¹⁷⁷Lu-anti-CD55 also enhanced the antitumor activity of cisplatin both in vitro and in vivo. These data suggest ¹⁷⁷Lu-anti-CD55 antibody is a promising theranostic agent for pleural metastatic lung cancer.

Beyond the Role of CD55 as a Complement Component

The complement is a part of the immune system that plays several roles in removing pathogens. Despite the importance of the complement system, the exact role of each component has been overlooked because the complement system was thought to be a nonspecific humoral immune mechanism that worked against pathogens. Decay-accelerating factor (DAF or CD55) is a known inhibitor of the complement system and has recently attracted substantial attention due to its role in various diseases, such as cancer, protein-losing enteropathy, and malaria. Some protein-losing enteropathy cases are caused by CD55 deficiency, which leads to complement hyperactivation, malabsorption, and angiopathic thrombosis. In addition, CD55 has been reported to be an essential host receptor for infection by the malaria parasite. Moreover, CD55 is a ligand of the seven-span transmembrane receptor CD97. Since CD55 is present in various cells, the functional role of CD55 has been expanded by showing that CD55 is associated with a variety of diseases, including cancer, malaria, protein-losing enteropathy, paroxysmal nocturnal hemoglobinuria, and autoimmune diseases. This review summarizes the current understanding of CD55 and the role of CD55 in these diseases. It also provides insight into the development of novel drugs for the diagnosis and treatment of diseases associated with CD55.

Candidate SNP markers of reproductive potential are predicted by a significant change in the affinity of TATA-binding protein for human gene promoters

BACKGROUND

The progress of medicine, science, technology, education, and culture improves, year by year, quality of life and life expectancy of the populace. The modern human has a chance to further improve the quality and duration of his/her life and the lives of his/her loved ones by bringing their lifestyle in line with their sequenced individual genomes. With this in mind, one of genome-based developments at the junction of personalized medicine and bioinformatics will be considered in this work, where we used two Web services: (i) SNP_TATA_Comparator to search for alleles with a single nucleotide polymorphism (SNP) that alters the affinity of TATA-binding protein (TBP) for the TATA boxes of human gene promoters and (ii) PubMed to look for retrospective clinical reviews on changes in physiological indicators of reproductive potential in carriers of these alleles.

RESULTS

A total of 126 SNP markers of female reproductive potential, capable of altering the affinity of TBP for gene promoters, were found using the two above-mentioned Web services. For example, 10 candidate SNP markers of thrombosis (e.g., rs563763767) can cause overproduction of coagulation inducers. In pregnant women, Hughes syndrome provokes thrombosis with a fatal outcome although this syndrome can be diagnosed and eliminated even at the earliest stages of its development. Thus, in women carrying any of the above SNPs, preventive treatment of this syndrome before a planned pregnancy can reduce the risk of death. Similarly, seven SNP markers predicted here (e.g., rs774688955) can elevate the risk of myocardial infarction. In line with Bowles' lifespan theory, women carrying any of these SNPs may modify their lifestyle to improve their longevity if they can take under advisement that risks of myocardial infarction increase with age of the mother, total number of pregnancies, in multiple pregnancies, pregnancies under the age of 20, hypertension, preeclampsia, menstrual cycle irregularity, and in women smokers.

CONCLUSIONS

According to Bowles' lifespan theory-which links reproductive potential, quality of life, and life expectancy-the above information was compiled for those who would like to reduce risks of diseases corresponding to alleles in own sequenced genomes. Candidate SNP markers can focus the clinical analysis of unannotated SNPs, after which they may become useful for people who would like to bring their lifestyle in line with their sequenced individual genomes.

Tissue factor-factor VIIa complex triggers protease activated receptor 2-dependent growth factor release and migration in ovarian cancer

OBJECTIVE

Enhanced tissue factor (TF) expression in epithelial ovarian cancer (EOC) is associated with aggressive disease. Our objective was to evaluate the role of the TF-factor VIIa-protease-activated receptor-2 (PAR-2) pathway in human EOC.

METHODS

TCGA RNAseq data from EOC databases were analyzed for PAR expression. Cell and microparticle (MP) associated TF protein expression (Western blot) and MP-associated coagulant activity were determined in human EOC (SKOV-3, OVCAR-3 and CaOV-3) and control cell lines. PAR-1 and PAR-2 protein expressions were similarly examined. The PAR dependence of VEGF-A release (ELISA) and chemotactic migration in response to FVIIa and cellular proliferation in response to thrombin was evaluated with small molecule antagonists.

RESULTS

Relative mRNA expression consistently demonstrated PAR-2>PAR-1≫PAR-3/4 in multiple EOC datasets. Human EOC cell line lysates confirmed expression of TF, PAR-1 and PAR-2 proteins. MPs isolated from EOC cell lines demonstrated markedly enhanced (4-10 fold) TF coagulant activity relative to control cell lines. FVIIa induced a dose-dependent increase in VEGF-A release (2.5-3 fold) from EOC cell lines that was abrogated by the PAR-2 antagonist ENMD-1068. FVIIa treatment of CaOV-3 and OVCAR-3 cells resulted in increased chemotactic migration that was abolished by ENMD-1068. Thrombin induced dose-dependent EOC cell line proliferation was completely reversed by the PAR-1 antagonist vorapaxar. Small molecule antagonists had no effect on these phenotypes without protease present.

CONCLUSIONS

Enhanced activity of the TF-FVIIa-PAR-2 axis may contribute to the EOC progression via PAR-2 dependent signaling that supports an angiogenic and invasive phenotype and local thrombin generation supporting PAR-1 dependent proliferation.

Reciprocal links between venous thromboembolism, coagulation factors and ovarian cancer progression

Ovarian cancer is the most lethal gynecological malignancy, which is due to late presentation. Treating advanced stage ovarian cancer is difficult, and tumor recurrence and chemoresistance frequently occur. In addition, early detection remains a major challenge as there are no early warning signs and no appropriate biomarkers. To reduce mortality rates of ovarian cancer patients, novel drug targets and biomarkers are needed. We postulate that hemostatic keyplayers are of importance when combatting ovarian cancer. The majority of ovarian cancer patients have abnormal hemostatic blood serum marker levels, which indicate an activated coagulation system. This makes patients more prone to experiencing venous thromboembolism (VTE), and the occurrence of VTE in ovarian cancer patients adversely affects survival. Coagulation activation also promotes tumor progression as it influences tumor biology at several stages and the decreased survival rates associated with ovarian cancer-associated thrombosis are more likely due to cancer metastasis rather than to fatal thromboembolic events. In this review, we will discuss; (1) Population studies that address the bidirectional relationship between VTE and ovarian cancer, and the most important risk factors involved; (2) The mechanisms of coagulation factors and platelets that are critically involved in the development of VTE, and the progression of ovarian cancer; (3) Roles and future directions of coagulation factors in ovarian cancer therapy, and in diagnosis and prognosis of ovarian cancer as biomarkers.

Microvesicle-associated tissue factor procoagulant activity for the preoperative diagnosis of ovarian cancer

BACKGROUND

Tissue factor (TF) is involved in tumor growth and metastasis and contributes to venous thromboembolism (VTE) in cancer, including gynecological malignancies. The diagnostic value of microvesicle-associated TF procoagulant activity (MV TF PCA) in women with suspected ovarian cancer, however, has not been studied.

OBJECTIVE

To evaluate MV TF PCA as a diagnostic tool in women with an ovarian mass of unknown etiology and as a predictive biomarker for perioperative VTE.

METHODS

Plasma MVs were isolated by high-speed centrifugation and analyzed for TF-specific PCA by single-stage clotting assay. In addition, plasma TF antigen and soluble P-selectin (sCD62P) were measured by ELISA.

RESULTS

D-Dimer, MV TF PCA, and sCD62P, but not the tumor marker, CA-125, significantly differentiated patients with malignant (n=40) from those with benign tumors (n=15) and healthy controls (n=34). In cancer patients, only D-Dimer and CA-125 correlated with the FIGO stage. An abnormal D-dimer had the highest sensitivity for the diagnosis of cancer, while MV TF PCA above the ROC curve-derived cut-off value of 182U/mL had the highest specificity. By multivariate logistic regression analysis, addition of MV TF PCA conferred diagnostic benefit to the single variables, CA-125 (p=0.052) and D-dimer (p=0.019). Perioperative VTE occurred in 16% of cancer patients and was associated with an advanced FIGO stage, but not MV TF PCA. There was no difference in plasma TF antigen levels between study groups.

CONCLUSIONS

MV TF PCA, but not plasma TF antigen, may provide valuable additional information for the diagnostic work-up of women with suspected ovarian cancer.

Tissue Factor-Factor VII Complex As a Key Regulator of Ovarian Cancer Phenotypes

Tissue factor (TF) is an integral membrane protein widely expressed in normal human cells. Blood coagulation factor VII (fVII) is a key enzyme in the extrinsic coagulation cascade that is predominantly secreted by hepatocytes and released into the bloodstream. The TF–fVII complex is aberrantly expressed on the surface of cancer cells, including ovarian cancer cells. This procoagulant complex can initiate intracellular signaling mechanisms, resulting in malignant phenotypes. Cancer tissues are chronically exposed to hypoxia. TF and fVII can be induced in response to hypoxia in ovarian cancer cells at the gene expression level, leading to the autonomous production of the TF–fVII complex. Here, we discuss the roles of the TF–fVII complex in the induction of malignant phenotypes in ovarian cancer cells. The hypoxic nature of ovarian cancer tissues and the roles of TF expression in endometriosis are discussed. Arguments will be extended to potential strategies to treat ovarian cancers based on our current knowledge of TF–fVII function.

Analysis of microarray-identified genes and microRNAs associated with drug resistance in ovarian cancer

The aim of this study was to identify potential microRNAs and genes associated with drug resistance in ovarian cancer through web-available microarrays. The drug resistant-related microRNA microarray dataset GS54665 and mRNA dataset GSE33482, GSE28646, and GSE15372 were downloaded from the Gene Expression Omnibus database. Dysregulated microRNAs/genes were screened with GEO2R and were further identified in SKOV3 (SKOV3/DDP) and A2780 (A2780/DDP) cells by real-time quantitative PCR (qRT-PCR), and then their associations with drug resistance was analyzed by comprehensive bioinformatic analyses. Nine microRNAs (microRNA-199a-5p, microRNA-199a-3p, microRNA-199b-3p, microRNA-215, microRNA-335, microRNA-18b, microRNA-363, microRNA-645 and microRNA-141) and 38 genes were identified to be differentially expressed in drug-resistant ovarian cancer cells, with seven genes (NHSL1, EPHA3, USP51, ZSCAN4, EPHA7, SNCA and PI15) exhibited exactly the same expression trends in all three microarrays. Biological process annotation and pathway enrichment analysis of the 9 microRNAs and 38 genes identified several drug resistant-related signaling pathways, and the microRNA-mRNA interaction revealed the existence of a targeted regulatory relationship between the 9 microRNAs and most of the 38 genes. The expression of 9 microRNAs and the 7 genes by qRT-PCR in SKOV3/DDP and A2780/DDP cells indicating a consistent expression profile with the microarrays. Among those, the expression of EPHA7 and PI15 were negatively correlated with that of microRNA-141, and they were also identified as potential targets of this microRNA via microRNA-mRNA interaction. We thus concluded that microRNA-141, EPHA7, and PI15 might jointly participate in the regulation of drug resistance in ovarian cancer and serve as potential targets in targeted therapies.

Protein engineering to target complement evasion in cancer

The complement system is composed of soluble factors in plasma that enhance or "complement" immune-mediated killing through innate and adaptive mechanisms. Activation of complement causes recruitment of immune cells; opsonization of coated cells; and direct killing of affected cells through a membrane attack complex (MAC). Tumor cells up-regulate complement inhibitory factors - one of several strategies to evade the immune system. In many cases as the tumor progresses, dramatic increases in complement inhibitory factors are found on these cells. This review focuses on the classic complement pathway and the role of major complement inhibitory factors in cancer immune evasion as well as on how current protein engineering efforts are being employed to increase complement fixing or to reverse complement resistance leading to better therapeutic outcomes in oncology. Strategies discussed include engineering of antibodies to enhance complement fixation, antibodies that neutralize complement inhibitory proteins as well as engineered constructs that specifically target inhibition of the complement system.

Tumour and microparticle tissue factor expression and cancer thrombosis

Cancer is frequently complicated by venous thromboembolic events (VTE), which pose a significant health burden due to the associated high morbidity and mortality rates, yet the exact details of the pathophysiological mechanisms underlying their development are yet to be fully elucidated. Tissue factor (TF), the primary initiator of coagulation, is often overexpressed in malignancy and as such is a prime candidate in predicting the hypercoagulable state. Further exploration of this potential role has identified increases in the number of TF-expressing microparticles (MP) in the circulation of cancer patients, in particular in those known to have high incidences of thromboembolic complications. The risk of VTE in cancer is found to be further elevated by chemotherapy. Chemotherapy may, in eliciting cancer cell apoptosis, result in an increase in release of circulating procoagulant MP. We discuss a potential role of elevated tumour TF expression and increased circulating TF-positive MP in predicting VTE risk.

(111)Indium Labelling of Recombinant Activated Coagulation Factor VII: In Vitro and Preliminary In Vivo Studies in Healthy Rats

The aim of this study is to investigate whether (111)Indium-labelled recombinant FVIIa (rFVIIa) could be a potential radiopharmaceutical for localization of bleeding sources. DTPA-conjugated rFVIIa was radiolabelled with (111)In chloride. In vitro binding efficiency of (111)In-DTPA-rFVIIa to F1A2-Mab-sepharose was 99% in buffer, while it was 88-82% in serum. The binding efficiency of (111)In-DTPA-rFVIIa to TF (1-209)-sepharose was 48% in buffer whereas 39%-36% in serum, respectively. In vivo experiment was conducted in healthy rats, and gamma camera images were taken immediately after iv. administration of 1.6-1.8 MBq (111)In-DTPA-rFVIIa up to 120-130 min. Five min after administration of (111)In-DTPA-rFVIIa, percentage of (111)In activity was 6.0% in the cardiac region and 24.5% in the liver region. After 2 hours activity was decreased to 3.3% in heart while it had increased to 42.0% in the liver. The (111)In-DTPA-rFVIIa might be a potential radiopharmaceutical for visualisation of tissues with significant TF expression such as acute bleeding lesions in the gastrointestinal tract.