A novel angiogenesis inhibitor bevacizumab induces apoptosis in the rat endometriosis model

Antibiotic Therapy and Vaginal Microbiota Transplantation Reduce Endometriosis Disease Progression in Female Mice via NF-κB Signaling Pathway

Endometriosis (EMS) is a disease characterized by estrogen-dependent, chronic inflammatory, and annoying symptoms, which inflicts about 10% reproductive-age women. The diagnosis of endometriosis mainly depends on pathological examination after surgical resection while the pathogenesis of EMS is not clear enough. Surgical resection and drug therapy (including painkillers and hormone therapy, especially gonadotropin-releasing hormone analogs, GnRH-a) are widely used, but they are expensive and have many side effects. There are few studies on vaginal microorganisms in women with endometriosis. We collected vaginal secretions from women with EMS confirmed by pathology and demonstrated that they were different from that of healthy women by 16s rRNA high-throughput sequencing. Additionally, we established the EMS model in female mice by intraperitoneally injecting fragments from donor mice (3-week growth). Then, the mice were treated with mixed antibiotics (vagina) and NF-κB signaling pathway inhibitors (intraperitoneal injection), respectively. The result suggested that the ectopic lesions were inhibited. In addition, inflammatory cytokines IL-1β, IL-6, and TNF-α in peritoneal fluid, cell proliferation marker ki-67, and macrophage marker Iba-1 in ectopic lesions decreased significantly from that of mock mice. We also observed similar results as above by vaginal microbiota transplantation (VMT) and subcutaneous injection of leuprorelin acetate (LA, one of GnRH-a) for mice with EMS. These results showed that vaginal use of antibiotics or VMT is helpful to treat endometriosis in mice. However, due to the great difference between human and mouse vaginal microbiota, its mechanism and clinical transformation application still need to be further studied in the future.

The effectiveness of antioxidant therapy (vitamin C) in an experimentally induced mouse model of ovarian endometriosis

Objectives:

This study investigates the therapeutic effect of vitamin C on the development of endometrial lesions and fecundity disorders in the ovarian induction model of mouse endometriosis.

Methods:

Ovarian endometriosis was surgically induced in 14 NMRI female mice (treatment group, N = 7) and (control group, N = 7). Three days after the second surgery (to assess endometriotic implant), the mice were randomized into two intervention groups: control (placebo) and treatment (50 mg/kg vitamin C every two days orally for four weeks) groups. In the oestrus phase, the mice were sacrificed. In macroscopic assessment, endometriotic implants were evaluated in size, volume, weight, growth score and adhesion score. The microscopic assessment examined the ovarian tissue (the number of antral follicles, corpus luteum and atretic follicles) and endometriotic lesion (histologic and trichrome fibrosis scores).

Results:

Post-treatment implant volume, growth score, adhesion extent score and adhesion severity score were significantly lower in the treatment group (vitamin C) in comparison with the control group (placebo) (p < 0.0001). The difference between the median weight of endometriotic implants, epithelialization of implant tissue, trichrome fibrosis scores and follicle number in the two groups (treatment and control) was statistically significant (p < 0.05). Atretic follicles were significantly decreased after vitamin C therapy (p < 0.05). Although the numbers of corpus luteum seemed to be more preserved in specimens from the control group, there was no statistical significance between the two groups’ histological scores.

Conclusion:

As a result, we may imply that vitamin C has a significant effect on reducing the induction and growth of endometrial implants, improving the fecundity function of ovaries, and consequently prevention of endometriosis-associated cancers. Further research is needed to improve targeted interventions resulting in the prevention and treatment of human endometriosis.

Antiangiogenic Therapy as a New Strategy in the Treatment of Endometriosis? The First Case Report

Angiogenesis plays a pivotal role in implantation and development of ectopic endometrial lesions. Thus, the potential usefulness of anti-angiogenic therapies has been speculated. Several reports describe their usefulness in animal models. Nonetheless this therapy has not been tested on humans yet. Here we report the outcome of a patient treated for a severe endometriosis with Bevacizumab (Avastin®), a monoclonal antibody directed against the vascular endothelial growth (VEGF). After a first-look laparoscopy with confirmatory biopsies was performed, three doses of Bevacizumab at 2-week intervals were administered. The therapy showed a well-tolerated profile and the prompt disappearance of the therapy-refractory chronic dysmenorrhea. A suppression of metabolic activity at the PET-scan compared to the basal one performed at diagnosis was also recorded. Furthermore, compared to the diagnostic biopsies prior the treatment, we documented a shift in the hormonal receptors profile toward a higher expression of progesterone and estrogen receptors in the endometriotic lesions.

Anti-angiogenic Properties of Bevacizumab Improve Respiratory System Inflammation in Ovalbumin-Induced Rat Model of Asthma

Studies on the bronchial vascular bed have revealed that the number of blood vessels in the lamina propria and under the mucosa of the lung tissue increases in patients suffering from mild to severe asthma. Thus, in this study, a new strategy was employed in respiratory system disorders by angiogenesis inhibition in an ovalbumin (OVA)-induced rat model of asthma. Twenty-one male Wistar albino rats, 8 weeks old, were randomly divided into three groups (n = 7 in each group), including (1) control group, (2) OVA-treated group, and (3) OVA + Bmab (bevacizumab drug). On days 1 and 8, 1 mg of OVA and aluminum hydroxide in sterile phosphate-buffered saline (PBS) were intraperitoneally injected to rats in groups 2 and 3. The control group was only subject to intraperitoneal injection of saline on days 1 and 8. One week after the last injection, the rats (groups 2 and 3) were exposed to OVA inhalation for 30 min at 2-day intervals from days 15 to 25. After sensitization and challenge with OVA, the OVA + Bmab group (group 3) were treated with a 5 mg/kg bevacizumab drug. Genes and protein expression of IL-1β and TNF-α and the expression of vascular endothelial growth factor (VEGF) protein were assessed by real-time PCR and immunohistochemistry respectively, in lung tissue. OVA exposure increased mucosal secretion and inflammatory cell populations in lung tissue and OVA-specific IgE level in serum. Also, VEGF and cytokine factor expression were significantly elevated in the OVA-induced asthma model (p ≤ 0.05). However, rats in OVA + Bmab group showed significantly a decrease in VEGF and IL-1β and TNF-α genes as well as proteins (p ≤ 0.05). The results showed that bevacizumab efficiently diminished bronchial inflammation via downregulation of VEGF expression, followed by inflammatory cells population and cytokines reduction. Angiogenesis inhibition in rats with induced asthma not only suppresses the inflammatory process through blocking VEGF expression but also inhibits the development of new blood vessels and progressing asthmatic attacks.

Role of medical treatment of endometriosis

Endometriosis is a chronic benign disease that affects women of reproductive age. Medical therapy is often the first line of management for women with endometriosis in order to ameliorate symptoms or to prevent post-surgical disease recurrence. Currently, there are several medical options for the management of patients with endometriosis and long-term treatments should balance clinical efficacy (controlling pain symptoms and preventing recurrence of disease after surgery) with an acceptable safety-profile. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of chronic inflammatory conditions, being efficacious in relieving primary dysmenorrhea. Combined oral contraceptives and progestins, available for multiple routes of administration, are commonly administered as first-line hormonal therapies. Several studies demonstrated that they succeed in improving pain symptoms in the majority of patients; moreover, they are well tolerated and not expensive. Gonadotropin-releasing hormone-agonists are prescribed when first line therapies are ineffective, not tolerated or contraindicated. Even if these drugs are efficacious in treating women not responding to COCs or progestins, they are not orally available and have a less favorable tolerability profile (needing an appropriate add-back therapy). Because few data are available on long-term efficacy and safety of aromatase inhibitors they should be reserved only for women with symptoms who are refractory to other treatments only in a research environment. Almost all of the currently available treatment options for endometriosis suppress ovarian function and are not curative. For this reason, research into new drugs is unsurprisingly demanding. Amongst the drugs currently under investigation, gonadotropin-releasing hormone antagonists have shown most promise, currently in late-stage clinical development. There is a number of potential future therapies currently tested only in vitro, in animal models of endometriosis or in early clinical studies with a small sample size. Further studies are necessary to conclude whether these treatments would be of value for the treatment of endometriosis.

Impact of Bevacizumab on Experimentally Induced Endometriotic Lesions: Angiogenesis, Invasion, Apoptosis, and Cell Proliferation

Endometriosis is responsible for pain symptoms with great impact on the patient's quality of life. Several medication lines have been studied aiming at its definitive treatment. Among them, angiogenesis inhibitor factors may be effective given that angiogenesis has fundamental role in the establishment and growth of endometriotic lesions. In this study, we investigated the influence of bevacizumab, anti-factor drug of endothelial growth (anti-VEGF), used at two different dosages, in experimental endometriosis induced in rats. After the induction of endometriosis lesions in rats, they were divided in 3 groups: control group, no treatment, and two other groups were treated with different dosages of the same medication for 4 weeks. At the end of the treatment, endometriotic lesions were removed and evaluated regarding area of lesions, presence of endometrial tissue in microscopy, positivity for anti-VEGF antibody in immunohistochemistry, and gene expression of Pcna, Mmp9, Tp63, and Vegfa. Bevacizumab acted by reducing the area of lesions in the groups that received medication (p = 0.002) and reducing gene expression to Tp63 in lesions (p = 0.04). There was no significant result in other evaluations. We observed that there was significant reduction of the area of lesions among groups, suggesting that bevacizumab has a positive effect on disease control. The gene expression of Tp63 was significantly lower in the group that received high dose of the drug when compared with the other two groups; therefore, we concluded that bevacizumab acts by reducing cell proliferation and differentiation in lesions, constituting a real option for treating endometriosis.

Angiogenesis in Breast Cancer Progression, Diagnosis, and Treatment

Angiogenesis is a significant event in a wide range of healthy and diseased conditions. This process frequently involves vasodilation and an increase in vascular permeability. Numerous players referred to as angiogenic factors, work in tandem to facilitate the outgrowth of endothelial cells (EC) and the consequent vascularity. Conversely, angiogenic factors could also feature in pathological conditions. Angiogenesis is a critical factor in the development of tumors and metastases in numerous cancers. An increased level of angiogenesis is associated with decreased survival in breast cancer patients. Therefore, a good understanding of the angiogenic mechanism holds a promise of providing effective treatments for breast cancer progression, thereby enhancing patients' survival. Disrupting the initiation and progression of this process by targeting angiogenic factors such as vascular endothelial growth factor (Vegf)-one of the most potent member of the VEGF family- or by targeting transcription factors, such as Hypoxia-Inducible Factors (HIFs) that act as angiogenic regulators, have been considered potential treatment options for several types of cancers. The objective of this review is to highlight the mechanism of angiogenesis in diseases, specifically its role in the progression of malignancy in breast cancer, as well as to highlight the undergoing research in the development of angiogenesis-targeting therapies.

Silymarin amplifies apoptosis in ectopic endometrial tissue in rats with endometriosis; implication on growth factor GDNF, ERK1/2 and Bcl-6b expression

The present prospective study was done to evaluate the effect of silymarin (SMN) on endometriotic-like legions establishment and growth in experimentally-induced endometriosis. For this purpose, the experimental endometriosis was induced in 12 rats and then the animals subdivided into endometriosis-sole and SMN (50 mg kg^-1, orally)+endometriosis groups. Following 28 days, the legions establishment, size, Glial cell line-derived neurotrophic factor (GDNF), gfrα1, B Cell Lymphoma 6 (Bcl-6b), Bcl-2, extracellular regulator kinase (ERK1/2) expression ratios, angiogenesis, the apoptosis and fibrosis indices were investigated. The SMN significantly (P < 0.05) decreased the enometriotic-like legions establishment and size, decreased mRNA levels of GDNF, gfrα1, Bcl-6b and Bcl-2 and remarkably diminished GDNF, gfrα1, Bcl-6b and Bcl-2-positive cells distribution/mm² of tissue versus endometriosis-sole group. The SMN + endometriosis group exhibited a significant (P < 0.05) enhancement in ERK1/2 expression and represented diminished vascularized area and increased apoptosis and fibrosis indices, as well. In conclusion, the SMN by down-regulating GDNF and its receptor gfrα1 expression inhibits GDNF-gfrα1 complex generation and consequently suppresses Bcl-6b expression. Moreover, the SMN by enhancing the ERK1/2 expression and by suppressing the Bcl-2 expression promotes the apoptosis pathway. Finally, the SMN by down-regulating the angiogenesis ratio accelerates apoptosis and consequently induces severe fibrosis in endometriotic-like legions.

Anti-Angiogenic Alternative and Complementary Medicines for the Treatment of Endometriosis: A Review of Potential Molecular Mechanisms

Endometriosis is caused by the growth or infiltration of endometrial tissues outside of the endometrium and myometrium. Symptoms include pain and infertility. Surgery and hormonal therapy are widely used in Western medicine for the treatment of endometriosis; however, the side effects associated with this practice include disease recurrence and menopause, which can severely influence quality of life. Angiogenesis is the main biological mechanism underlying the development of endometriosis. Numerous natural products and Chinese medicines with potent anti-angiogenic effects have been investigated, and the molecular basis underlying their therapeutic effects in endometriosis has been explored. This review aims to describe natural products and compounds that suppress angiogenesis associated with endometriosis and to assess their diverse molecular mechanisms of action. Furthermore, this review provides a source of information relating to alternative and complementary therapeutic products that mediate anti-angiogenesis. An extensive review of the literature and electronic databases, such as the China National Knowledge Infrastructure, PubMed, and Embase, was conducted using the keywords 'endometriosis,' 'traditional Chinese medicine,' 'Chinese herbal medicine,' 'natural compounds,' and 'anti-angiogenic' therapy. Anti-angiogenic therapy is an emerging strategy for the treatment of endometriosis. Natural anti-angiogenic products and Chinese medicines provide several beneficial clinical effects, including pain relief. In this review, we summarize clinical trials and experimental studies of endometriosis using natural products and Chinese medicines. In particular, we focus on anti-angiogenic products and alternative and complementary medicines for the treatment of endometriosis and additionally examine their therapeutic efficacy and mechanisms of action. Anti-angiogenic natural products and/or compounds provide a new approach for the treatment of endometriosis. Future work will require randomized trials with larger numbers of subjects, as well as long-term follow-up to confirm the findings described here.

Investigational drugs for the treatment of endometriosis, an update on recent developments

INTRODUCTION

Endometriosis is a hormone-dependent benign chronic disease that requires a chronic medical therapy. Although currently available drugs are efficacious in treating endometriosis-related pain, some women experience partial or no improvement. Moreover, the recurrence of symptoms is expected after discontinuation of the therapies. Currently, new drugs are under intense clinical investigation for the treatment of endometriosis.

AREAS COVERED

This review aims to offer the reader a complete and updated overview on new investigational drugs and early molecular targets for the treatment of endometriosis. The authors describe the pre-clinical and clinical development of these agents.

EXPERT OPINION

Among the drugs under investigation, late clinical trials on gonadotropin-releasing hormone antagonists (GnRH-ant) showed the most promising results for the treatment of endometriosis. Aromatase inhibitors (AIs) are efficacious in treating endometriosis related pain symptoms but they cause significant adverse effects that limit their long-term use. New targets have been identified to produce drugs for the treatment of endometriosis, but the majority of these new compounds have only been investigated in laboratory studies or early clinical trials. Thus, further clinical research is required in order to elucidate their efficacy and safety in human.

[New medical treatments for painful endometriosis: CNGOF-HAS Endometriosis Guidelines]

OBJECTIVE

The objective of this work is to evaluate the place of new treatments in the management of endometriosis outside the context of infertility.

METHODS

A review of the literature was conducted by consulting Medline data until July 2017.

RESULTS

Dienogest is effective compared to placebo in short term (NP2) and long term (NP4) for the treatment of painful endometriosis. In comparison with GnRH agonists, dienogest is also effective in terms of decreased pain and improved quality of life in non-operated patients (NP2) as well as for recurrence of lesions and symptomatology postoperatively (NP2). Data on GnRH antagonists, selective progesterone receptor modulators as well as selective inhibitors (anti-TNF-α, matrix metalloprotease inhibitors, angiogenesis growth factor inhibitors) are insufficient to provide evidence of interest in clinical practice for the management of painful endometriosis (NP3).

CONCLUSION

Dienogest is recommended as second-line therapy for the management of painful endometriosis (Grade B). Because of lack of evidence, aromatase inhibitors, elagolix, SERM, SPRM and anti-TNF-α are not recommended for the management of painful endometriosis (Grade C).

Icon immunoconjugate treatment results in regression of red lesions in a non-human primate (Papio anubis) model of endometriosis

Endometriosis is a common condition in reproductive-aged women characterized by ectopic endometrial lesions of varied appearance, including red, white, blue, black or powder burn coloration, which contribute to chronic pain and infertility. The immunoconjugate molecule (Icon) targets Tissue Factor, a transmembrane receptor for Factor VII/VIIa that is aberrantly expressed in the endothelium supporting ectopic endometrial tissue. Icon has been shown to cause regression of endometriosis in a murine model of disease but prior to this study had not been tested in non-human primates. This study evaluated Icon as a novel treatment for endometriosis in non-human primates (Papio anubis) using an adenoviral vector (AdIcon) delivery system. Female baboons (n = 15) underwent surgical induction of endometriosis. After laparoscopic confirmation of endometriosis lesions 6-weeks post-surgery, the treatment group (n = 7) received weekly intraperitoneal injections of viral particles carrying the sequence for Icon, resulting in expression of the protein, while the control group (n = 8) received no treatment. Icon preferentially reduced the number and volume of red vascularized lesions. Icon may present a novel treatment for endometriosis by degrading red vascularized lesions, likely by targeting tissue factor aberrantly expressed in the lesion vasculature.

MicroRNAs in cancer metastasis and angiogenesis

Cancer metastasis is a malignant process by which tumor cells migrate from their primary site of origin to other organs. It is the main cause of poor prognosis in cancer patients. Angiogenesis is the process of generating new blood capillaries from pre-existing vasculature. It plays a vital role in primary tumor growth and distant metastasis. MicroRNAs are small non-coding RNAs involved in regulating normal physiological processes as well as cancer pathogenesis. They suppress gene expression by specifically binding to the 3′-untranslated region (3′-UTR) of their target genes. They can thus act as oncogenes or tumor suppressors depending on the function of their target genes. MicroRNAs have shown great promise for use in anti-metastatic cancer therapy. In this article, we review the roles of various miRNAs in cancer angiogenesis and metastasis and highlight their potential for use in future therapies against metastatic cancer.

Efficacy comparison of oral rosuvastatin versus oral progesterone and bevacizumab on regression of surgically endometriotic implants in rats

This study hypothesizes that oral rosuvastatin, oral dienogest and intraperitoneal bevacizumab might improve endometriosis in randomly selected female Wistar albino rats with surgically endometriotic implants. Thirty female Wistar albino rats with surgically endometriotic implants were randomized into three treatment groups: oral rosuvastatin (20 mg kg/day; oral rosuvastatin group 1; n = 10), oral progesterone (dienogest group 2; n = 10) and intraperitoneal bevacizumab (2.5 mg/kg of single intraperitoneal injection of bevacizumab; bevacizumab group 3; n = 10), for 10 days. Post-treatment variables were compared. The oral rosuvastatin group showed higher reduction for the glandular epithelium and uterine vessels of histopathological scores values than the oral progesterone group (both, p < 0.017, respectively). The median glandular epithelium and uterine vessels and histopathological scores values did not show a statistically significant difference between group 1 and group 3 (p > 0.017). Endometrial thickness values and uterine volume values were more significantly reduced in the oral rosuvastatin group than the oral progesterone group (both, p < 0.017, respectively). Moreover, endometrial thickness and uterine volume values were not different in groups wecompared with group 3 (p > 0.017). In conclusion, oral rosuvastatin and intraperitoneal injection of bevacizumab may cause more significant regression of surgically endometriotic implants in rats than oral progesterone medications.

Mutational analysis of mitochondrial tRNA genes in patients with lung cancer

Mutations in mitochondrial tRNA (mt-tRNA) genes have been found to be associated with various diseases including lung cancer. To understand the possible relationship between mtRNA mutations and lung cancer, we sequenced the 22 mt-tRNA genes from 200 lung cancer blood samples, as well as 100 healthy subjects. As a result, five mutations were identified including the tRNA^Ala T5655C, tRNA^Arg T10454C, tRNA^Leu(CUN) A12330G, tRNA^Ser(UCN) T7505C and tRNA^Thr G15927A. These mutations were absent in the healthy subjects. These mutations and polymorphisms were localized at the highly conserved nucleotides of the corresponding mitochondrial tRNAs, which are critical for the tRNA steady state level and may result in failure in the tRNA metabolism. Moreover, through the application of the pathogenicity scoring system, we found that only the T10454C mutation should be classified as a “neutral polymorphism,” while the other mutations were regarded as “definitely pathogenic.” Taken together, our data indicate that tRNA genes are the hot-spots for pathogenic mutations associated with lung cancer. Our findings may provide valuable information for pathophysiology, management and genetic counseling of lung cancer.

Viburnum opulus L.: A remedy for the treatment of endometriosis demonstrated by rat model of surgically-induced endometriosis

ETHNOPHARMACOLOGICAL RELEVANCE

Endometriosis is a gynecological disorder characterized by the presence of endometrial tissue outside the uterine cavity. The fruits of Viburnum opulus L. have been used to treat gynecological disorders including primary and secondary dysmenorrhea and ovarian cysts.

MATERIALS AND METHODS

Air-dried and powdered fruits of V. opulus were extracted sequentially with n-hexane, ethyl acetate (EtOAc), and methanol (MeOH), respectively for four days. Endometriosis was induced by suturing 15mm piece of endometrium into abdominal wall of Sprague Dawley rats. In second laparotomy, the dimensions of endometrial implants were measured and intra-abdominal adhesions were scored. The abdomen was closed. Extracts were daily administered to the rats. At the end of the experiment, rats were sacrified and endometriotic foci areas and intra-abdominal adhesions were re-evaluated. The tissues were also histopathologically investigated. Furthermore, tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) levels of peritoneal fluid were measured. HPLC analyses were conducted on the most potent EtOAc and MeOH extracts to determine the amount of the major compound, chlorogenic acid.

RESULTS

The endometriotic volumes were found to be reduced significantly in the EtOAc extract-administered group to 30.1mm³ and in the MeOH extract-administered group to 34.7mm³ as compared to the control group. No adhesion was observed in the reference and EtOAc groups. Histopathological data also supported the results. Both EtOAc and MeOH extract-administered groups displayed significant remission in the levels of TNF-α, VEGF and IL-6. When the active extracts were subjected to HPLC analysis, chlorogenic acid was found to be the major compound and the amount of this compound was calculated as 0.5112±0.0012mg and 1.7072±0.0277mg/100mg extract, repectively.

CONCLUSIONS

The results of the present study indicate that the effectiveness of the fruit extract of V. opulus could be partially attributed chlorogenic acid. Other phenolic compounds could potentiate the activity due to their amount.

Efficacy of Anti-VEGF/VEGFR Agents on Animal Models of Endometriosis: A Systematic Review and Meta-Analysis

Background/Objective

Vascular endothelial growth factor (VEGF) is the most important promotor of angiogenesis. Some studies indicate that anti-angiogenic agents that interfere with VEGF and its receptor (VEGFR), i.e., anti-VEGF/VEGFR agents, may be applied to treat endometriosis. This meta-analysis investigated the efficacy of anti-VEGF/VEGFR agents in animal models of endometriosis.

Methods

A systematic literature search was performed for animal studies published in English or Chinese from January 1995 to June 2016, which evaluated the effect of anti-VEGF/VEGFR agents on endometriosis. The databases were: PubMed, Web of Science, BIOSIS, Embase, and CNKI. The quality of included studies was assessed using the SYRCLE tool. The random-effect models were used to combine the results of selected studies. Heterogeneity was assessed using H²statistic and I² statistic. Subgroup analyses were performed to determine the source of heterogeneity in endometriosis scores and follicle numbers.

Results

We identified 13 studies that used anti-VEGF/VEGFR agents in various animal models. The meta-analysis showed that anti-VEGF/VEGFR agents were associated with smaller size (standardized mean difference (SMD) –0.96, 95% CI –1.31 to –0.62; P < 0.0001) and weight (SMD –1.70, 95% CI –2.75 to –0.65; P = 0.002) of endometriosis lesions, relative to the untreated controls, as well as a lower incidence rate of endometriosis (risk ratio 0.26, 95% CI 0.07 to 0.93; P = 0.038) and endometriosis score (SMD –1.17, 95% CI –1.65 to –0.69; P < 0.0001); the number of follicles were similar (SMD –0.78, 95% CI –1.65 to 0.09; P = 0.08).

Conclusions

Anti-VEGF/VEGFR agents appeared to inhibit the growth of endometriosis, with no effect on ovarian function. Anti-angiogenic therapy may be a novel strategy in treating endometriosis.

Effect of rapamycin on endometriosis in mice

The aims of the present study were to investigate the impact of rapamycin (RAPA) on the endometriosis (EMS) lesions in severe combined immunodeficiency (SCID) mice, and to examine the possible mechanism involved in a novel therapy in EMS. Following the successful establishment of an EMS-SCID mouse model, the mice were randomly assigned into the RAPA, control and saline treatment groups. Subsequent to treatment for 2 weeks, the serum hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected using ELISA. The levels of HIF-1α and VEGF, as well as the size of EMS lesions, were compared among the three groups. In addition, the HIF-1α, VEGF and CD34 protein expression levels, and the microvessel density (MVD) of the lesions were determined by immunohistochemical analysis. Compared with the control and saline groups, the volume of EMS lesions in the RAPA-treated SCID mice was significantly reduced. Furthermore, the serum level and protein expression of VEGF, and the MVD in the lesions of the RAPA-treated group were significantly reduced when compared with the other two groups. These parameters were comparable in the control and saline groups. In conclusion, RAPA may inhibit the growth of endometriotic lesions, most possibly through the inhibition of the expression of VEGF in lesions, thereby inhibiting angiogenesis.