Treatment of endometriosis with a VEGF-targeted conditionally replicative adenovirus

Exercise and endometriosis-is there a promising future? A narrative review

BACKGROUND

Endometriosis is the leading cause of chronic pelvic pain in women of reproductive age with debilitating effects on quality of life, yet no cure exists. Exercise yields the potential in providing women with a non-invasive, non-pharmacological method of symptom control.

AIM(S)

Present up-to-date knowledge regarding how exercise may contribute to the management of endometriosis-related symptoms.

OBJECTIVE(S)

Discuss: 1. The pathophysiology surrounding exercise and endometriosis. 2. The role of exercise in endometriosis symptom control.

RATIONALE

Scientific literature has alluded to exercise being a favourable factor in the management of endometriosis-related symptoms. Moreover, current clinical guidelines for endometriosis fail to reflect the aforementioned benefits of exercise.

SEARCH STRATEGY

A search strategy using the terms 'endometriosis', 'endometriomas', 'exercise', and 'physical activity' was devised. Pubmed, Medline, Cochrane reviews, and Embase were reviewed.

INCLUSION CRITERIA

Interventional studies, within-subjects studies, randomised-control trials, systematic reviews, meta-analysis, cohort studies, publication since 2000.

EXCLUSION CRITERIA

Non-English publications, non-human studies.

RESULTS

Numerous studies have suggested positive effects for endometriosis patients who performed exercise exclusively or in conjunction with other therapies. Improvements in pain levels, quality of life, anxiety, and depression were noted.

DISCUSSION

Current research outlines promise regarding the potential benefit of exercise prescribing in patients with endometriosis as well as a synergy between exercise and hormonal therapies for the management of endometriosis-related symptoms. However, the current paucity of high-quality robust studies investigating these aspects of endometriosis management is an apparent obstacle to progression in this area.

CONCLUSION

For clinicians to incorporate exercise in managing endometriosis, clear recommendations regarding advice and benefits are needed.

Ethanol extract of basil (Ocimum Basilicum L.) leaves inhibits endometriosis growth in a mouse model by modulating vascular endothelial growth factor (VEGF) expression

The objective of this study was to examine the effect of administering an ethanol extract obtained from basil leaves on the expression of vascular endothelial growth factor (VEGF) and the severity of endometriosis lesions in a mouse model. A total of 28 female mice, aged 2-3 months and weighing 20-30 grams, were randomly divided into four groups: the control group (C), treatment group 1 (T1) receiving a dose of basil leaf ethanol extract (0.21 mg/g-BW), treatment group 2 (T2) receiving a higher dose (0.42 mg/g BW), and treatment group 3 (T3) receiving the highest dose (0.84 mg/g-BW). Each group underwent a 14-day treatment period, and tissue samples were collected on the 29th day. An immunohistochemical examination was conducted to assess the expression of VEGF and evaluate the severity of endometriosis lesions. The statistical analysis of VEGF expression revealed a significant difference (p=0.026; p<0.05), with the most pronounced effects observed when administering basil leaf ethanol extract at doses of 0.21 mg/g-BW and 0.42 mg/g-BW. Although not statistically significant (p=0.271; p<0.05), a reduction in the severity of endometriosis lesions was observed following the administration of basil leaf ethanol extract at doses of 0.21 mg/g-BW and 0.42 mg/g-BW. Administering basil leaf ethanol extract at doses of 0.21 mg/g-BW and 0.42 mg/g-BW effectively decreased VEGF expression and limited the severity of endometriosis lesions.

Prolactin and pain of endometriosis

Women experience chronic pain more often than men with some pain conditions being specific to women while others are more prevalent in women. Prolactin, a neuropeptide hormone with higher serum levels in women, has recently been demonstrated in preclinical studies to sensitize nociceptive sensory neurons in a sexually dimorphic manner. Dysregulation of prolactin and prolactin receptors may be responsible for increased pain especially in female predominant conditions such as migraine, fibromyalgia, and pelvic pain. In this review, we focus on the role of prolactin in endometriosis, a condition characterized by pelvic pain and infertility that affects a large proportion of women during their reproductive age. We discuss the symptoms and pathology of endometriosis and discuss how different sources of prolactin secretion may contribute to this disease. We highlight our current understanding of prolactin-mediated mechanisms of nociceptor sensitization in females and how this mechanism may apply to endometriosis. Lastly, we report the results of a systematic review of clinical studies conducted by searching the PubMed and EMBASE databases to identify association between endometriosis and blood levels of prolactin. The results of this search strongly indicate that serum prolactin levels are increased in patients with endometriosis and support the possibility that high levels of prolactin may promote pelvic pain in these patients and increase vulnerability to other comorbid pain conditions likely by dysregulating prolactin receptor expression. Targeting of prolactin and prolactin receptors may improve management of pain associated with endometriosis.

Endometriosis-Associated Angiogenesis and Anti-angiogenic Therapy for Endometriosis

Endometriosis is a known estrogen-dependent inflammatory disease affecting reproductive-aged women. Common symptoms include pelvic pain, dysmenorrhea, dyspareunia, heavy menstrual bleeding, and infertility. The exact etiology of endometriosis is largely unknown, and, thus, the diagnosis and treatment of endometriosis are challenging. A complex interplay of many molecular mechanisms is thought to aid in the progression of endometriosis, most notably angiogenesis. This mini-review examines our current knowledge of the molecular etiology of endometriosis-associated angiogenesis and discusses anti-angiogenic therapy, in the blockade of endometriosis-associated angiogenesis, as potential non-hormonal therapy for the treatment of endometriosis.

The Effect of Novel Medical Nonhormonal Treatments on the Angiogenesis of Endometriotic Lesions

Importance

Irrespective of the precise mechanisms leading to endometriosis, angiogenesis is essential for the establishment and long-term proliferation of the disease. As current surgical and medical management options for women with endometriosis have substantial drawbacks and limitations, novel agents are needed and molecules targeting the angiogenic cascade could serve as potential candidates.

Objective

Our aim was to review current data about the role of angiogenesis in the pathophysiology of endometriosis and summarize the novel antiangiogenic agents that could be potentially used in clinical management of patients with endometriosis.

Evidence Acquisition

Original research and review articles were retrieved through a computerized literature search.

Results

Loss of balance between angiogenic activators and suppressors triggers the nonphysiological angiogenesis observed in endometriotic lesions. Several proangiogenic mediators have been identified and most of them have demonstrated increased concentrations in the peritoneal fluid and/or serum of women with endometriosis. Among the antiangiogenic molecules, anti-vascular endothelial growth factor agents, dopamine agonists, romidepsin, and statins have shown the most promising results so far.

Conclusions and Relevance

Given the limitations of current treatments of endometriosis, there is a need for novel, more efficient agents. Antiangiogenic molecules could be used potentially in clinical management of women with endometriosis; however, their safety and efficiency should be carefully assessed prior to that. Further large prospective trials in humans are needed before any treatment is introduced into daily clinical practice.

A randomized exploratory trial to assess the effects of resveratrol on VEGF and TNF-α 2 expression in endometriosis women

Resveratrol, a naturally synthesized polyphenolic compound found in some fruits, has anti neoplastic, anti-inflammatory, anti-oxidative, and anti-angiogenic properties. Angiogenesis is an important process in endometriosis which provides blood supply for implantation, proliferation and survival of endometriotic lesions. In this study, we assessed the effects of resveratrol on vascular endothelial growth factor (VEGF) and tumor necrosis factor alpha (TNF-α) expression in the eutopic endometrium of infertile patients with endometriosis within the window of implantation as a randomized exploratory trial. Subjects, who confirmed their endometriosis (stage III-IV) by a pathologist after laparoscopic surgery, were recruited to the present trial. A total of 34 patients were randomly divided into treatment (n = 17) and control (n = 17) groups, beside the routine protocol for treatment of endometriosis, they received resveratrol and placebo (400 mg) for 12-14 weeks, respectively. Endometrial tissue was collected from both groups before and after the intervention in the mid-secretory phase. Gene and protein expression levels of VEGF and TNF-α in the eutopic endometrium were assessed by Real-Time PCR and Western blotting, respectively. VEGF and TNF-α gene and protein levels in the treatment group showed significant decrease following intervention. It seems resveratrol may improve the endometrium of endometriosis patients in window of implantation period by modifying the expression of VEGF and TNF-α but further investigations are needed to reveal the potential role of this compound.

Exosome-mediated microRNA-138 and vascular endothelial growth factor in endometriosis through inflammation and apoptosis via the nuclear factor-κB signaling pathway

Endometriosis (Ems) is a condition that refers to the ectopic implantation and growth of endometrial tissue outside the uterine cavity. The aim of the present study was to investigate the role of microRNA-138 (miR-138) in Ems and the possible underlying mechanism. Flow cytometry was measured CD11b level, cell proliferation was measured using MTT assay and lactate dehydrogenase (LDH) assays was analyzed using LDH activity kits. Cell apoptosis was measured using Annexin V-FITC/PI double staining apoptosis detection kit and DAPI assays. ELISA assay and western blot analysis were used to measure protein expression determination. It was first observed that miR-138 expression was markedly downregulated and the CD11b level was reduced in Ems mice compared with the control group. Subsequently, miR-138 expression was downregulated in the uterine endothelial cells co-cultured with THP-1 cells, which resulted in decreased apoptosis and increased inflammation in the uterine endothelial cells. By contrast, upregulation of miR-138 by mimic transfection increased the proliferation and reduced inflammation in uterine endothelial cells. In addition, in the co-culture of uterine endothelial and THP-1 cells, downregulation of miR-138 induced the expression of nuclear factor (NF)-κB and vascular endothelial growth factor (VEGF) proteins in THP-1 cells. Furthermore, treatment with an NF-κB inhibitor and downregulation of miR-138 in the co-culture of uterine endothelial and THP-1 cells reduced inflammation. VEGF inhibitor treatment and downregulation of miR-138 in this cell co-culture promoted the proliferation of uterine endothelial cells. These results suggested that uterine endothelial cells promoted miR-138 to induce exosome-mediated inflammation and apoptosis in Ems through the VEGF/NF-κB signaling pathway.

Anti-angiogenic treatment of endometriosis via anti-VEGFA siRNA delivery by means of peptide-based carrier in a rat subcutaneous model

Development of gene therapy for endometriosis requires inhibition of vascularization in endometrial lesions. We have previously developed CXCR4 receptor-targeted siRNA carrier L1 and observed efficient RNAi-mediated down-regulation of VEGFA gene expression in endothelial cells followed by decrease in VEGFA protein production and inhibition of cell migration. In this study we evaluated L1 carrier as non-viral vector for anti-VEGFA siRNA delivery into endometrial implants in rat subcutaneous endometriosis model created by subcutaneous auto-transplantation of uterus horn's fragments. Therapeutic anti-angiogenic efficiency of anti-VEGFA siRNA/L1 polyplexes was evaluated by lesion size measurement, histopathologic examination, immunohistochemical staining and real-time reverse transcriptase-PCR analysis. After in vivo administration of anti-VEGFA siRNA we observed a 55-60% inhibition of endometriotic lesions growth and approximately two-fold decrease in VEGFA gene expression in comparison with untreated implants. Results of immunohistochemical examination of endometriotic lesions confirmed anti-angiogenic effects of anti-VEGFA siRNA/L1 polyplexes. Ultimately, our results demonstrate the efficiency of anti-angiogenic treatment of EM by means of anti-VEGFA siRNA delivery with L1 peptide-based carrier.

Effects of cisplatin on surgically induced endometriosis in a rat model

Research has strongly suggested that the features of endometriosis serve as a precursor lesion of ovarian cancer. Cisplatin (CDDP) is the preferred drug against these cancer types. The present study investigated the effects of CDDP on surgically induced endometriosis in a rat model. Endometriosis was surgically induced by the autologous transplantation of endometrial tissue. A total of 36 model rats were randomly divided into three groups. The rats in Group 1 (control group, n=12) received no medication. The rats in Group 2 (n=12) and Group 3 (n=12) were administered 35 mg/m² CDDP and 70 mg/m² CDDP, respectively, every four days. All rats were treated for a total of 24 days. The growth and histologic scores of the implants were calculated. The expression of protein markers, including vascular endothelial growth factor (VEGF), aromatase P450 (P450arom), transforming growth factor-β (TGF-β) and matrix metalloproteinase (MMP)-2, were assessed using immunohistochemistry, an enzyme-linked immunosorbent assay and western blot analysis. Following CDDP treatment, the mean implant sizes were significantly reduced in Groups 2 and 3 compared with the control group (P=0.01). The mean histologic scores were also significantly lower in Groups 2 and 3. Furthermore, the protein expression of VEGF, P450arom, TGF-β and MMP-2 was significantly lower in Groups 2 and 3 when compared with the control group. A loss of hair was observed in 4 rats, which only occurred in Group 3. A dose-dependent effect was observed in the two CDDP-treated groups. In conclusion, the expression of proliferation- and angiogenesis-associated proteins was significantly lower following treatment with CDDP. CDDP caused a significant regression in the size of the endometriotic implants and induced atrophy of these lesions in rats.

Mesenchymal stem cells: a promising tool for targeted gene therapy of endometriosis

Endometriosis is a leading, benign gynecological disorder around the world. Last few years have witnessed tremendous growth in the field of endometriosis and endometrial stem-cell research. Despite advancements in the biology and pathology of endometriosis, disease recurrence is still an enigma. Gene therapy holds promise in treating many pathologic conditions including endometriosis. Mesenchymal stem cells (MSCs) serve as ideal candidates for regenerative medicine and cell-based therapies. Owing to their specificity to the endometrium, residing endometrial MSC populations could be utilized as ideal candidates for targeting endometrial disorders. Recently, we demonstrated their flexibility for gene transduction using adenoviral vectors. The review highlights the potential of endometrial MSCs in devising targeted gene therapies for endometriosis.

Fertile ground: human endometrial programming and lessons in health and disease

The human endometrium is a highly dynamic tissue that is cyclically shed, repaired, regenerated and remodelled, primarily under the orchestration of oestrogen and progesterone, in preparation for embryo implantation. Humans are among the very few species that menstruate and that, consequently, are equipped with unique cellular and molecular mechanisms controlling these cyclic processes. Many reproductive pathologies are specific to menstruating species, and studies in animal models rarely translate to humans. Abnormal remodelling and regeneration of the human endometrium leads to a range of reproductive complications. Furthermore, the processes regulating endometrial remodelling and implantation, including those controlling hormonal impact, breakdown and repair, stem/progenitor cell activation, inflammation and cell invasion have broad applications to other fields. This Review presents current knowledge regarding the normal and abnormal function of the human endometrium. The development of biomarkers for prediction of uterine diseases and pregnancy disorders and future avenues of investigation to improve fertility and enhance endometrial function are also discussed.

Effects of cisplatin and letrozole on surgically induced endometriosis and comparison of the two medications in a rat model

This study was to investigate the effects of cisplatin (CDDP) and letrozole on surgically induced endometriosis and comparison of the two drugs in a rat model. Endometriosis was surgically induced by autologous transplantation of endometrial pieces. Thirty model rats were divided into three groups, randomly. Group 1 (n=10) served as control and received no medication. Group 2 (n=10) received 0.2mg/kg/day of oral letrozole. Group 3 (n=10) received 35mg/m(2) CDDP via peritoneal perfusion every four days. All the rats were treated for 24days. The growth and histologic score of the implants were evaluated. The proliferation- and angiogenesis-associated proteins were assessed using immunohistochemistry and western blotting. The serum sex hormones were assayed using ELISA. After the medication, the growth and histologic score of the implants were significantly lower in the 2 and 3 groups than in the control group. The protein expressions of vascular endothelial growth factor (VEGF), aromatase P450 (P450arom), transforming growth factor-beta (TGF-β), and matrix metalloproteinase (MMP)-2, were significantly lower in groups 2 and 3 than in the control group. Further, the P450arom level was lower in the letrozole group than in the CDDP group. The TGF-β and MMP-2 levels were lower in the CDDP group than in the letrozole group. Serum T level was significantly higher in the letrozole group, and serum E2 level was lower in the letrozole group. In conclusion, cisplatin and letrozole caused similar regression of the implants in the endometriosis model rats. But their effects on the proliferation- and angiogenesis-associated protein expressions and the serum sex hormone levels were different. Cisplatin and letrozole might cause the effects in the endometriotic foci through different mechanism.

Effects of the hypoxia-inducible factor-1 inhibitor echinomycin on vascular endothelial growth factor production and apoptosis in human ectopic endometriotic stromal cells

Recent evidence points to a possible role for hypoxia-inducible factor (HIF)-1 in the pathogenesis and development of endometriosis. The objectives of this study were to investigate the critical role of HIF-1 in endometriosis and the effect of the HIF-1 inhibitor echinomycin on human ectopic endometriotic stromal cells (eESCs). Ectopic endometriotic tissues were obtained from 20 patients, who received an operation for ovarian endometriomas. We examined vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1 (SDF-1) production, HIF-1 expression, cell proliferation and apoptosis of eESCs. Cobalt chloride (CoCl2) significantly induced expression of HIF-1α protein and VEGF production in a time-dependent manner in eESCs, but reduced SDF-1 production. VEGF production was significantly suppressed by treatment of 100 nM echinomycin without causing cell toxicity, but 0.1-10 nM echinomycin or 100 nM progestin had no significant effect. SDF-1 production was not affected by echinomycin treatment at any dose. Echinomycin inhibited cell proliferation and induced apoptotic cell death of the eESCs, and significantly inhibited expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL. Echinomycin inhibits VEGF production and induces apoptosis of eESCs by suppression of Bcl-2 and Bcl-xL. These findings suggest the unique therapeutic potential for echinomycin as an inhibitor of HIF-1 activation for endometriosis treatment.

Novel agents for the medical treatment of endometriosis

PURPOSE OF REVIEW

Current medical treatments for endometriosis-associated pain, including oral contraceptives, progestins and GnRH agonists, are partially effective and have significant side-effects. The purpose of this review is to present new hormonal and nonhormonal treatment for endometriosis.

RECENT FINDINGS

At present, the ideal drug that can prevent, inhibit or stop development of endometriosis, reduce associated pain or infertility and allow conception does not exist. New drugs in development for endometriosis modulate GnRH, estrogen and/or progesterone receptors, or target endometriosis-associated inflammation, angiogenesis, adhesion and/or tissue invasion. Most have been tested in rodents, and have been evaluated in more relevant animal models like nonhuman primates (baboons), but only a few, that is GnRH antagonists, have been tested in human randomized controlled trials. Important safety and efficacy issues remain a concern, as steroid receptors, inflammation, adhesion, angiogenesis and tissue invasion are key factors in physiological events like ovulation, menstruation and embryo implantation.

SUMMARY

New drugs for the medical treatment of endometriosis targeting both hormonal (GnRH, estrogen and progesterone receptors) and nonhormonal pathways (inflammation, angiogenesis, adhesions, tissue invasion) are promising, but their efficacy and safety need to be established in randomized human trials before they can be used in clinical practice.

A conditionally replicative adenovirus, CRAd-S-pK7, can target endometriosis with a cell-killing effect

BACKGROUND

Novel therapeutic approaches for endometriosis based on molecular strategies may prove to be useful. Conditionally replicative adenoviruses (CRAds) are designed to exploit key differences between target and normal cells. The wild-type adenovirus (Adwt) promoter can be replaced by tissue-specific promoters, allowing viral replication only in target cells. Viral infectivity can be enhanced by altering Ad tropism via fiber modification. We investigated whether CRAds can be used to target endometriosis and determined the most efficient transcriptional- and transductional-targeting strategy.

METHODS

An in vitro study was carried out using human endometriotic cell lines, 11Z (epithelial) and 22B (stromal), normal human ovarian surface epithelial cell line (NOSE006) and primary human endometriosis cells. A total of 9 promoters and 12 Ad tropism modifications were screened by means of a luciferase reporter assay. From this screening data, three CRAds (CRAd-S-pK7, CRAd-S-RGD, CRAd-S-F5/3sigma1, all incorporating the survivin promoter but with different fiber modifications) were selected to perform experiments using Adwt and a replication-deficient virus as controls. CRAds were constructed using a plasmid recombination system. Viral-binding capacity, rates of entry and DNA replication were evaluated by quantitative real-time PCR of viral genome copy. Cell-killing effects were determined by crystal violet staining and a cell viability assay for different concentrations of viral particles per cell.

RESULTS

Comparison of promoters demonstrated that the survivin promoter exhibited the highest induction in both endometriotic cell lines. Among the fiber-modified viruses, the polylysine modification (pK7) showed the best infection enhancement. CRAd-S-pK7 was validated as the optimal CRAd to target endometriosis in terms of binding ability, entry kinetics, DNA replication and cell-killing effect. CRAd-S-pK7 also exhibited a high level of DNA replication in primary endometriosis cells.

CONCLUSIONS

CRAd-S-pK7 has the best infection and cell-killing effect in the context of endometriosis. It could prove to be a useful novel method to target refractory cases of endometriosis.