Macrophages and Immune Responses in Uterine Fibroids.

Uterine fibroids represent the most common benign tumors of the uterus. They are considered a typical fibrotic disorder. In fact, the extracellular matrix (ECM) proteins-above all, collagen 1A1, fibronectin and versican-are upregulated in this pathology. The uterine fibroids etiology has not yet been clarified, and this represents an important matter about their resolution. A model has been proposed according to which the formation of an altered ECM could be the result of an excessive wound healing, in turn driven by a dysregulated inflammation process. A lot of molecules act in the complex inflammatory response. Macrophages have a great flexibility since they can assume different phenotypes leading to the tissue repair process. The dysregulation of macrophage proliferation, accumulation and infiltration could lead to an uncontrolled tissue repair and to the consequent pathological fibrosis. In addition, molecules such as monocyte chemoattractant protein-1 (MCP-1), granulocyte macrophage-colony-stimulating factor (GM-CSF), transforming growth factor-beta (TGF-ß), activin A and tumor necrosis factor-alfa (TNF-α) were demonstrated to play an important role in the macrophage action within the uncontrolled tissue repair that contributes to the pathological fibrosis that represents a typical feature of the uterine fibroids.

PD-L1 Expression and Tumor-infiltrating Lymphocytes in Uterine Smooth Muscle Tumors: Implications for Immunotherapy.

Immunotherapies targeting the PD-1/PD-L1 checkpoint axis are of growing interest for the treatment of mesenchymal neoplasms. However, PD-L1 expression and tumor-associated lymphocytes have not been well-investigated in uterine smooth muscle tumors. Forty-nine uterine smooth muscle tumors (23 leiomyosarcomas, 8 smooth muscle tumors of uncertain malignant potential [STUMP], 7 atypical leiomyomas, and 11 benign leiomyomas) were evaluated for tumoral and tumor-associated immune PD-L1 expression and tumor-associated T-cell infiltration. ALK immunohistochemistry was performed to exclude inflammatory myofibroblastic tumors. Tumor PD-L1 expression was seen in 70% of leiomyosarcomas and 14% of atypical leiomyomas; no cases of STUMP or benign leiomyoma demonstrated tumoral PD-L1. PD-L1 positivity was seen in tumor-associated immune cells in 78% of leiomyosarcomas, 25% of STUMP, no cases of atypical leiomyomas, and 9% of benign leiomyomas. Of the 23 leiomyosarcomas, 15 (65%) had a combined positive score ≥1, while of the 26 other uterine smooth muscle tumors, only 2 (8%) had a combined positive score ≥1. Tumor-associated CD8+ cells were highest among leiomyosarcomas (mean: 87/high-power fields vs. 17/high-power fields for nonleiomyosarcomas), and were significantly associated with PD-L1 expression. One PD-L1, CD8-enriched leiomyosarcoma showed an ALK overexpression suggesting possible classification as inflammatory myofibroblastic tumor, but otherwise lacked morphologic features of this entity. Leiomyosarcomas demonstrate significantly higher PD-L1 expression and cytotoxic T-cell infiltration when compared with other uterine smooth muscle tumors. These data suggest the possibility that treatment with targeted immunotherapy may be appropriate in a selected population of patients with leiomyosarcoma and, potentially, in related tumors bearing ALK rearrangements.

[Growth mechanisms and morphological structural features of large uterine leiomyoma]. / Mekhanizmy rosta i osobennosti morfologicheskogo stroeniia leiomiomy matki bol'shogo razmera.

OBJECTIVE: To investigate the growth mechanisms of large uterine leiomyoma (LULM) on the basis of a clinical morphology examination, by providing immunohistochemical (IHC) characteristics of the expression of growth factors (transforming growth factor-beta (TGFß) and platelet-derived endothelial cell growth factor (PD-ECGF)) and markers of stemness (CD117/c-kit, Connexin 43, Nestin) and proliferation (Ki-67). SUBJECT AND METHODS: The investigators examined surgical specimens from 38 women diagnosed with simple uterine leiomyoma (ULM), who had been divided into two groups: 1) 21 patients with LULM (>6 cm in diameter) (a study group); 2) 17 patients with small ULM (<4 cm in diameter) (a comparison group). Each group was also divided into two age subgroups (younger (<45 years) and older (≥45 years) subgroups (1a (n=12), 1b (n=9), 2a (n=8) and 2b (n=9), respectively. Histological specimens were used to make IHC examination with antibodies against TGFß, PD-ECGF, CD117/c-kit, Connexin 43, Nestin, and Ki-67. RESULTS: The growth mechanisms of LULM of simple histological structure were found to be associated with the larger number of growth zones in the tumors, with their enhanced cellular proliferative activity, and with the appearance of cells with signs of stemness, which is combined with the preserved subsequent maturation of tumor cells and determines the benign nature of LULM. CONCLUSION: There were differences in the molecular profile of LULM and small ULM, as well as LULM in perimenopausal and young women by the expression levels of Ki-67, TGFß, PD-ECGF, CD117, and Connexin 43, which can be used for diagnosis, prediction, and development of targeted therapies.

Blood Serum Levels of Proinflammatory Cytokines (IL-1ß, IL-6, TNFα, IL-8, IL-12p70, and IFNγ) in Patients with Uterine Myoma.

We analyzed cytokine profile in blood serum of patients with uterine myoma and revealed significantly reduced level of IFNγ and a tendency towards a decrease in the levels of IL-1ß and TNFα; the levels of IL-6, IL-8, and IL-12p70 did not differ from those in healthy women. The drop in the concentrations of factors responsible for inflammation and angiogenesis in tissues are unfavorable for proliferation and differentiation of the uterine tissues.

Oxidative stress: a key regulator of leiomyoma cell survival.

OBJECTIVE: To determine the effects of attenuating oxidative stress with the use of dichloroacetate (DCA) on the expression of key redox enzymes myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) as well as on apoptosis. DESIGN: Prospective experimental study. SETTING: University medical center. PATIENT(S): Cells established from myometrium and uterine fibroid from the same patients. INTERVENTION(S): Cells were exposed to normal (20% O2) or hypoxic (2% O2) conditions for 24 hours with or without DCA (20 µg/mL), a metabolic modulator that shifts anaerobic to aerobic metabolism. MAIN OUTCOME MEASURE(S): Nitrate/nitrite (iNOS activity indicator), iNOS, Bcl-2/Bax ratio, MPO, and caspase-3 activities and levels were determined by means of Greiss assay, real-time reverse-transcription polymerase chain reaction, and ELISA. Data were analyzed with the use of SPSS by means of one-way analysis of variance with Tukey post hoc analysis and independent t tests. RESULT(S): MPO, iNOS, and nitrate/nitrite expression were higher in leiomyoma than in myometrial cells, and they were further enhanced by hypoxia in myometrial cells. Treatment with the use of DCA decreased MPO, iNOS, and nitrate/nitrite levels and negated the effect of hypoxia in both types of cells. Leiomyoma cells showed less apoptosis, as indicated by both caspase-3 activity and the Bcl-2/Bax ratio, than myometrial cells. Hypoxia further decreased apoptosis in myometrial cells with no further effect on leiomyoma cells. Treatment with DCA resulted in increased apoptosis in both types of cells, even in the presence of hypoxia. CONCLUSION(S): Shifting anaerobic to aerobic metabolism with the use of DCA resulted in an increase in apoptosis in leiomyoma cells and protected myometrial cells from the acquisition of the leiomyoma-like phenotype.

Primary Intraventricular Leiomyoma in an Immunocompetent Patient: First Case Report and Review of the Literature.

BACKGROUND: Primary intracranial leiomyoma is an extremely rare occurrence of a low-grade mesenchymal tumor characterized by a proliferation of smooth muscle cells. When present, these lesions predominantly occur in immunocompromised patients in the setting of infection or transplant and have not been known to involve the ventricular system of the brain. In this report, we describe a case of primary leiomyoma of the lateral ventricle in an immunocompetent patient. CASE DESCRIPTION: A 30-year-old man with no medical history presented with progressive diplopia and occipital headaches. Magnetic resonance imaging of the brain revealed a homogenously enhancing mass of the left lateral ventricle with associated cerebral edema. The patient underwent interhemispheric transcallosal craniotomy for resection for symptom alleviation and surgical diagnosis. Histopathology and immunohistochemistry was subsequently consistent with that of leiomyoma. Genetic probing for Epstein-Barr virus was negative. Computed tomography of the chest and abdomen failed to uncover a primary tumor. The patient did well postoperatively and was discharged 3 days after resection. At a two-and-a-half year follow-up, there continued to be no radiologic or clinical evidence of recurrence. CONCLUSIONS: To date and to our knowledge, there are fewer than 25 reported cases of primary intracranial leiomyoma, with only 13 occurring in immunocompetent individuals. We believe this is the first report of this tumor type occurring within the ventricular system of the brain. As such, leiomyoma should be considered as a rare etiology in the differential diagnosis of intraventricular lesions.

PTPN22 and uterine leiomyomas.

OBJECTIVE: It has been suggested that the development of uterine leiomyomas is positively influenced by an immune system in a chronically inflammatory state and that a lower level of regulating T cell (Treg cells) would play a central role. Since it has been suggested that the W620 variant of protein tyrosine phosphatase non-receptor type 22 (PTPN22) decreases the number of Treg cells, we investigated a possible relationship between PTPN22 polymorphism and uterine leiomyomas. STUDY DESIGN: We studied 203 white women from Rome who were hospitalized for symptomatic leiomyomas requiring surgical intervention. These women were considered in a previous paper regarding the relationship between ACP1 and dimension of leiomyomas. As controls we studied 355 healthy women from the same population with comparable age and without clinical evidence of leiomyomas. All women gave written informed consent to participate to the study. Chi square test of independence and T-test for difference between means were performed by SPSS package. RESULTS: Considering the whole sample, a borderline association between PTPN22 and leiomyomas was observed: the *C/*T genotype is more frequent in cases than in controls. This association is marked and statistically significant in younger women only. The main diameter of tumor is significantly greater in *C/*T than in *C/*C women. This effect is present in younger women only. The *C/*T genotype also shows a higher tendency to intramural localization, but no effect of age is observed upon this association. CONCLUSIONS: The data suggest a positive effect of *C/*T genotype on susceptibility to leiomyomas in younger women. In these women a *C/*T genotype favors the growth of leiomyomas.

Use of dietary phytochemicals to target inflammation, fibrosis, proliferation, and angiogenesis in uterine tissues: promising options for prevention and treatment of uterine fibroids?

Uterine leiomyomas (fibroids, myomas) are the most common benign tumors of female reproductive tract. They are highly prevalent, with 70-80% of women burdened by the end of their reproductive years. Fibroids are a leading cause of pelvic pain, abnormal vaginal bleeding, pressure on the bladder, miscarriage, and infertility. They are the leading indication for hysterectomy, and costs exceed 6 billion dollars annually in the United States. Unfortunately, no long-term medical treatments are available. Dysregulation of inflammatory processes are thought to be involved in the initiation of leiomyoma and extracellular matrix deposition, cell proliferation, and angiogenesis are the key cellular events implicated in leiomyoma growth. In modern pharmaceutical industries, dietary phytochemicals are used as source of new potential drugs for many kinds of tumors. Dietary phytochemicals may exert therapeutic effects by interfering with key cellular events of the tumorigenesis process. At present, a negligible number of phytochemicals have been tested as therapeutic agents against fibroids. In this context, our aim was to introduce some of the potential dietary phytochemicals that have shown anti-inflammatory, antiproliferative, antifibrotic, and antiangiogenic activities in different biological systems. This review could be useful to stimulate the evaluation of these phytochemicals as possible therapies for uterine fibroids.

Endobronchial leiomyoma in an immunocompetent four-year-old female child.

Pulmonary leiomyoma are uncommonly encountered benign mesenchymal neoplasms in children, usually found in immunosuppressed individuals in association with human immunodeficiency virus or Ebstein-Barr virus infection. We describe an interesting case of a 4-year-old immunocompetent girl who presented with pleural effusion and lung collapse secondary to endobronchial leiomyoma. She underwent a left thoracotomy and a left pneumonectomy for excision of the bronchial mass.

Uterine NK cells regulate endometrial bleeding in women and are suppressed by the progesterone receptor modulator asoprisnil.

Uterine NK cells (uNK) play a role in the regulation of placentation, but their functions in nonpregnant endometrium are not understood. We have previously reported suppression of endometrial bleeding and alteration of spiral artery morphology in women exposed to asoprisnil, a progesterone receptor modulator. We now compare global endometrial gene expression in asoprisnil-treated versus control women, and we demonstrate a statistically significant reduction of genes in the IL-15 pathway, known to play a key role in uNK development and function. Suppression of IL-15 by asoprisnil was also observed at mRNA level (p < 0.05), and immunostaining for NK cell marker CD56 revealed a striking reduction of uNK in asoprisnil-treated endometrium (p < 0.001). IL-15 levels in normal endometrium are progesterone-responsive. Progesterone receptor (PR) positive stromal cells transcribe both IL-15 and IL-15RA. Thus, the response of stromal cells to progesterone will be to increase IL-15 trans-presentation to uNK, supporting their expansion and differentiation. In asoprisnil-treated endometrium, there is a marked downregulation of stromal PR expression and virtual absence of uNK. These novel findings indicate that the IL-15 pathway provides a missing link in the complex interplay among endometrial stromal cells, uNK, and spiral arteries affecting physiologic and pathologic endometrial bleeding.

Uterine leiomyoma with indolent B-lymphoblastic proliferation.

Uterine leiomyoma with TdT positive B lymphocytes infiltrating is very rare and may simulate precursor B-cell lymphoblastic lymphoma (B-LBL). To the best of our knowledge, this is the first description of such a lesion in English literature. A 51-year-old Chinese woman was noted a mass in her uterus in a routine physical examination. The myomectomy specimen was identified as a well-defined 8.0x6.8 cm tumor and the cut surface was fresh and yellow-tan. A massive small lymphocytic infiltration accompanied by plasma cells and histiocytes was noted in the leiomyoma but not in the surrounding non-neoplastic myometrial fibers. These cells were small in size without significant nuclear irregularities and mitotic figures can not been seen. Immunohistochemical analysis has shown some small lymphocytes were CD20+, CD79a+, Pax5+B cells and some were CD2+, CD3+, CD5+, CD43+T cells. The small B cells coexpressed TdT and Ki67 and were in patchy dense distribution. The postoperative course was uneventful within a 30-month follow-up period without chemotherapy and radiotherapy. The true nature of these TdT(+) B cells has not been determined.

Cytokine patterns differ seasonally between women with and without uterine leiomyomata.

PROBLEM: Uterine leiomyomata are the most common reproductive tumor in women, and their cause is not known. METHODS OF STUDY: Plasma samples from 155 women (74 with and 81 without ultrasound-confirmed leiomyoma) from a new study of leiomyoma risk factors in the Detroit, Michigan area, were examined for any cross-sectional associations between commonly examined cytokines and leiomyoma presence. RESULTS: Associations varied by season of sample collection defined a priori as winter (December-February) and non-winter seasons. In the winter months, interleukin (IL)13 and IL17 were positively and IP10 was inversely associated with having a leiomyoma. In the non-winter samples, VEGF, G-CSF, and IP10 were positively associated and Monocyte chemotactic protein-1, IL13, and IL17 were inversely associated with having a leiomyoma. Associations were not changed by adjustment for age or BMI. CONCLUSIONS: These data suggest that new insight into leiomyoma formation may be acquired through investigation of the immune system.

The effect of high-intensity focused ultrasound treatment on immune function in patients with uterine fibroids.

PURPOSE: The aim of this study was to investigate the effect of high-intensity focused ultrasound (HIFU) on immune function in patients with uterine fibroids, in a randomised comparison to conventional myomectomy. METHODS: The patients were assigned (1:1) to the HIFU group or the myomectomy (MY) group. Venous blood samples were collected 24 h before and 24 h and 72 h after operation. The percentages of CD4(+) and CD8(+) T cells and natural killer (NK) cells were quantified by flow cytometry (FCM). Serum levels of interleukin-2 (IL-2), IL-6 and IL-10 were determined using enzyme-linked immunosorbent assay. RESULTS: HIFU was associated with early ambulation, fewer post-operative complications, and shorter hospital stay (p < 0.001). The percentages of CD4(+) and CD8(+) T cells and NK cells in the HIFU group were not significantly altered after treatment compared with before treatment. In contrast, the numbers of these cells in the MY group decreased significantly 24 h after conventional myomectomy (p < 0.001). The CD4(+)/CD8(+) T cell ratios were also decreased significantly 24 h and 72 h after conventional myomectomy (p < 0.001). Serum levels of IL-6 and IL-10 increased after treatment in both groups. Peak IL-6 and IL-10 levels were significantly lower in the HIFU group than in the MY group (p < 0.001). In contrast, IL-2 level decreased significantly in the MY group compared to the HIFU group at 24 h post-operation (p < 0.001). CONCLUSIONS: Short-term post-operative immune function is better preserved after HIFU treatment. Better preserved immune function may reflect a reduction in tissue trauma after HIFU treatment and contribute to reduced post-operative complications.

Gallbladder leiomyoma in absence of immune system disorders: an unusual diagnosis.

Mesenchymal neoplasms of the gallbladder are rare and in particular leiomyomas of the gallbladder have been rarely reported, all of them in patients with immune system disorders.This is the first report in Spanish of a 23-year-old female patient with a gallbladder leiomyoma without associated immunodeficiency. The patient lacks a previous history of uterine leiomyoma or any other form of neoplasm. She refers several episodes of epygastralgia. A hydatic cyst led to an initial diagnosis and the gallbladder was removed by means of simple cholecystectomy. The abnormal macroscopic aspect of the sample prompted intraoperative biopsy which revealed a benign gallbladder angiomyoma. Subsequent immunohistochemical analysis of the resected sample yielded the diagnosis of intramural endocavitary leiomyoma negative for EBV and C-kit / CD-117. The patient has good general condition and remains asymptomatic 15 months after surgery.

Are uterine leiomyoma a consequence of a chronically inflammatory immune system?

The cumulative incidence of uterine leiomyoma at age 50 is ≈ 70% in White women and >80% in Black women. Although risk factor research is limited, increasing age, and being premenopausal, nulliparous or Black are risk factors for leiomyomas. Black women tend to have larger leiomyomas and be younger at diagnosis. Surprisingly little is known about the etiology or pathogenesis of uterine leiomyomas. Women with diagnosed uterine leiomyomas have higher healthcare costs - more than 2.5 times that of women without a diagnosis. In the United States, leiomyomas are the leading indication for hysterectomy. The proposed hypothesis is that leiomyomas are caused in part by a systemic immune milieu that is chronically inflammatory - one that predominates in T helper 17 (Th17) cytokines. Inflammation can be problematic if it is not well regulated. Should an inflammatory imbalance be demonstrated to be associated with leiomyoma development and growth, this would provide an avenue for development of preventative treatments (e.g., focus on anti-inflammatory pathways), which would substantially reduce the morbidity costs of these tumors and reduce a known health disparity.