The Potential of Immunotherapy for SMARCA4-Deficient Undifferentiated Uterine Sarcoma (SDUS).

(1) Background: SMARCA4-deficient undifferentiated uterine sarcoma (SDUS) is a rare and aggressive cancer that urgently requires novel therapeutic strategies. Despite the proven efficacy of immunotherapy in various cancer types, its application in SDUS remains largely unexplored. This study aims to investigate the immune microenvironment of SDUS to evaluate the feasibility of utilizing immunotherapy. (2) Methods: Multiplex immunofluorescence (mIF) was employed to examine the immune microenvironment in two cases of SDUS in comparison to other subtypes of endometrial stromal sarcomas (ESSs). This research involved a comprehensive evaluation of immune cell infiltration, cellular interactions, and spatial organization within the tumor immune microenvironment (TiME). Statistical analysis was performed to assess differences in immune cell densities and interactions between SDUS and other ESSs. (3) Results: SDUS exhibited a significantly higher density of cytotoxic T lymphocytes (CTLs), T helper (Th) cells, B cells, and macrophages compared to other ESSs. Notable cellular interactions included Th-CTL and Th-B cell interactions, which were more prominent in SDUS. The spatial analysis revealed distinct immune niches characterized by lymphocyte aggregation and a vascular-rich environment, suggesting an active and engaged immune microenvironment in SDUS. (4) Conclusions: The results suggest that SDUS exhibits a highly immunogenic TiME, characterized by substantial lymphocyte infiltration and dynamic cellular interactions. These findings highlight the potential of immunotherapy as an effective treatment approach for SDUS. However, given the small number of samples evaluated, these conclusions should be drawn with caution. This study underscores the importance of additional investigation into immune-targeted therapies for this challenging cancer subtype, with a larger sample size to validate and expand upon these preliminary findings.

Role of inflammation and immune response in the pathogenesis of uterine fibroids: Including their negative impact on reproductive outcomes.

Uterine fibroids (UFs), the most common tumors in women of reproductive age, are characterized by sex steroid-dependent growth and excessive deposition of extracellular matrix (ECM) surrounding UF smooth muscle cells. Women with symptomatic UFs experience heavy menstrual bleeding and consequent iron-deficiency anemia. They also have a risk of recurrent pregnancy loss, preterm birth, and cesarean delivery, indicating that UFs can negatively affect reproductive outcomes. Various types of immune cells, including innate and adaptive cells, are observed in UFs; however, the impact of these cells on the pathophysiology of UFs remains unclear. Inflammation may play important roles in the growth of UFs, and expression levels of proinflammatory and inflammatory cytokines, such as interleukin (IL)-1, IL-6, IL-10, TNF-α, and TGF-ß, are upregulated in UFs. These cytokines play important roles in the interaction between growth factors and ECM that is regulated by the sex steroids estrogen and progesterone. Furthermore, proinflammatory mediators are upregulated in females with UFs, with higher expression levels in the endometrium with submucosal and intramural UFs than in the endometrium without UFs, indicating that these proinflammatory cytokines may impair endometrial receptivity, leading to implantation failure in in vitro fertilization programs. Hormonal treatments using gonadotropin releasing hormone analogs and the selective progesterone receptor modulator ulipristal acetate significantly shrink UFs and improve UF-related symptoms. These compounds can regulate local inflammation in UFs and adjacent myometrium. Controlling and improving local inflammation caused by UFs may represent a novel therapeutic strategy for UFs and potentially improve reproductive outcomes in women with symptomatic UFs.

CD8-positive T-cell lymphoproliferative disorder of the uterus: a new subtype of indolent extranodal T-cell neoplasm?

A 51-year-old female with menorrhagia was found to have a cervical polyp. Polypectomy and endometrial curettage showed an atypical lymphoid infiltrate. Hysterectomy was performed, showing extensive myometrial infiltration by small, cytologically bland CD3-positive αß T cells with a non-activated cytotoxic phenotype and a low proliferative rate. PCR showed clonal TCR-ß gene rearrangement. Lymph nodes were uninvolved. PET-CT was negative. A diagnosis of CD8-positive T-cell lymphoproliferative disorder (T-LPD) was made. At 6 months, the patient was asymptomatic with a negative repeat PET-CT. A critical recent advance in the classification of lymphoid neoplasms is the recognition of indolent extranodal T-LPDs, including those of the gastrointestinal tract (T-cell and NK-cell types) and skin (small/medium CD4-positive and acral CD8-positive). However, T-LPDs of the uterus are rare. Two indolent T-LPDs of the uterus have been reported, both showing a CD8-positive, nonactivated cytotoxic phenotype, low proliferative rate, and clonal TCR rearrangement. Neither developed systemic disease nor recurrence. The etiology of indolent T-LPDs and their relationship to overt T-cell lymphomas remain poorly understood. T-LPDs of the uterus may arise from effector memory T-cells that establish long-term, tissueresident immunologic memory following exposure to fetal extravillous trophoblastic cell alloantigens during a previous pregnancy. Neither our patient nor the 2 previously reported had a current pregnancy or a known recent infection or toxic exposure, and the event(s) triggering evolution into T-LPD are unknown. Indolent T-LPDs can be encountered at new and unusual extranodal sites; knowledge of their clinicopathological features will help avoid unnecessary cytotoxic chemotherapy and improve understanding of this group of disorders.

Case report: Characterization of the immunologic and molecular landscape in a unique presentation of invasive lobular carcinoma with concurrent uterine carcinosarcoma treated with immunotherapy.

Invasive lobular breast cancer (ILC) is characterized by a relatively high risk for late recurrence and a unique metastatic pattern with an increased risk for metastasis to gynecologic organs and peritoneum. We present a unique case of recurrent ILC with metastasis to the abdominal peritoneum as well as the uterine myometrium and cervix. Treatment was complicated by the discovery of concomitant uterine carcinosarcoma. This patient was effectively treated with a combination of hormonal therapy for her metastatic ILC and a combination of chemotherapy and immunotherapy for uterine carcinosarcoma. Molecular evaluation revealed a characteristic CDH1 mutation within the ILC and a PI3KCA mutation within the uterine carcinosarcoma, both of which have been linked to epithelial-to-mesenchymal transitions. Examination of the tumor immune microenvironment revealed proportionally more cytotoxic NK cells. This robust immune infiltration may be an indicator of the response to immunotherapy observed in this tumor or a result of the metastatic breast cancer within the uterus. This report provides a characterization of the molecular and immunologic landscape in this case with metastatic ILC and uterine carcinosarcoma.

The immune landscape of uterine fibroids as determined by mass cytometry.

OBJECTIVE: To study the differences in immune cell profiles in uterine fibroids (Fibs) and matched myometrium (Myo). DESIGN: Observational study. SETTING: Laboratory study. PATIENT(S): The study included tissue that was collected from 10 pairs of Fib and matched Myo from women, not on hormonal medications, undergoing hysterectomy and myomectomy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Differences in immune cell and cytokine composition between Fib and matched Myo. RESULT(S): The mass cytometry analysis indicated that Fibs had a significantly higher number of natural killer (NK) cells, total macrophages, M2 macrophages, and conventional dendritic cells when compared with matched Myo from the same patient. In contrast, Fibs had significantly fewer CD3 and CD4 T cells when compared with Myo. The mass cytometry analysis results did not show any significant difference in the number of resting mast cells. Immunoflurorescent and immunohistochemical imaging confirmed the cytometry by time of flight results, showing a significantly higher number of NK cells, tryptase-positive mast cells indicative of mast cell activation, total macrophages, and M2 cells in Fibs and a significantly lower number of CD3 and CD4 T cells. The cytokine assay revealed significantly increased levels of human interferon α2, interleukin (IL)-1α, and platelet-derived growth factor AA and significantly lower levels of macrophage colony-stimulating factor and IL-1 receptor antagonist in Fib. CONCLUSION(S): Our results show significant differences in immune cell populations and cytokine levels between Fib and Myo. These differences could account for the increased inflammation in fib and a potential mechanism by which these tumors evade the immune system. These findings provide a foundation for further studies exploring the role of immune cells in Fib development.

Killer Function of Circulating Neutrophils in Relation to Cytokines in Uterine Myoma and Endometrial Cancer.

The study presents the killer functions of circulating neutrophils: myeloperoxidase activity, the ability to generate ROS, phagocytic activity, receptor status, NETosis, as well as the level of cytokines IL-2, IL-4, IL-6, IL-17A, and IL-18, granulocyte CSF, monocyte chemotactic protein 1, and neutrophil elastase in the serum of patients with uterine myoma and endometrial cancer (FIGO stages I-III). The phagocytic ability of neutrophils in uterine myoma was influenced by serum levels of granulocyte CSF and IL-2 in 54% of the total variance. The degranulation ability of neutrophils in endometrial cancer was determined by circulating IL-18 in 50% of the total variance. In uterine myoma, 66% of the total variance in neutrophil myeloperoxidase activity was explained by a model dependent on blood levels of IL-17A, IL-6, and IL-4. The risk of endometrial cancer increases when elevated levels of monocyte chemotactic protein 1 in circulating neutrophils are associated with reduced ability to capture particles via extracellular traps (96% probability).

The prevalence and prognostic impact of tumor-infiltrating lymphocytes in uterine carcinosarcoma.

OBJECTIVE: To examine the prevalence and prognostic role of tumor microenvironment (TME) markers in uterine carcinosarcoma (UCS) through immunohistochemical characterization. METHODS: The internal database of our institution was queried out for women with UCS who underwent surgery and thereafter postoperative chemotherapy with carboplatin and paclitaxel between January 2012 and December 2017. Tissue microarrays containing surgical samples of UCS from 57 women were assessed by immunohistochemistry for CD3, CD4, CD8, FOXP3, PD-1, PD-L1, and PD-L2. RESULTS: The mean age was 65.3 years (range, 49 to 79 years). For the epithelial component (E), CD3_E and CD4_E were highly expressed in 38 (66.7%) and in 40 (70.1%) patients, respectively, and were significantly associated with more advanced stages (p = 0.038 and p = 0.025, respectively). CD8_E was highly expressed in 42 (73.7%) patients, FOXP3_E 16 (28.1%), PD-1_E 35 (61.4%), PD-L1_E 27 (47.4%) and PD-L2_E 39 (68.4%). For the sarcomatous component (S), the prevalence of high expression was: CD3_S 6 (10.5%), CD4_S 20 (35.1%), CD8_S 44 (77.2%), FOXP3_S 8 (14%), PD-1_S 14 (24.6%), PD-L1_S 14 (24.6%) and PD-L2_S 8 (14%). By multivariate analysis, the CD8/FOXP3_S ratio (p = 0.026), CD4_E (p = 0.010), PD-L1_E (p = 0.013) and PD-L1_S (p = 0.008) markers significantly influenced progression-free survival. CD4/FOXP3_S ratio (p = 0.043), PD-1_E (p = 0.011), PD-L1_E (p = 0.036) and PD-L1_S (p = 0.028) had a significant association with overall survival. CONCLUSION: Some differences in UCS clinical outcomes may be due to the subtype of TILs and PD-1/PD-L1 axis immune checkpoint signaling.

Multiplexed imaging reveals an IFN-γ-driven inflammatory state in nivolumab-associated gastritis.

Immune checkpoint blockade using PD-1 inhibition is an effective approach for treating a wide variety of cancer subtypes. While lower gastrointestinal (GI) side effects are more common, upper gastrointestinal adverse events are rarely reported. Here, we present a case of nivolumab-associated autoimmune gastritis. To elucidate the immunology underlying this condition, we leverage multiplexed ion beam imaging by time-of-flight (MIBI-TOF) to identify the presence and proportion of infiltrating immune cells from a single section of biopsy specimen. Using MIBI-TOF, we analyze formalin-fixed, paraffin-embedded human gastric tissue with 28 labels simultaneously. Our analyses reveal a gastritis characterized by severe mucosal injury, interferon gamma (IFN-γ)-producing gastric epithelial cells, and mixed inflammation that includes CD8 and CD4 T cell infiltrates with reduced expression of granzyme B and FOXP3, respectively. Here, we provide a comprehensive multiplexed histopathological mapping of gastric tissue, which identifies IFN-γ-producing epithelial cells as possible contributors to the nivolumab-associated gastritis.

Co-expression Analysis of Genes and Tumor-Infiltrating Immune Cells in Metastatic Uterine Carcinosarcoma.

Uterine carcinosarcoma (UCS) is a malignant tumor with a high tendency to invasion and metastasis. However, the underlying invasion and metastasis mechanisms of UCS remain poorly understood. Genetic alteration and tumor-infiltrating immune cells play important roles in tumorigenesis, progression, and metastasis. To better understand the underlying mechanisms of UCS, we screened tumor-infiltrating immune cells by applying CIBERSORT algorithm and constructed nomograms to predict the prognosis of UCS patients based on metastasis-specific tumor-infiltrating immune cells and genes, and demonstrated their utility by the high AUC values. Combining gene co-expression and experimental validation results, we propose a potential mechanism of AK8, MPZ, and mast cells activated might play important parts in UCS metastasis.

Current Status of Clinical Trials for Cervical and Uterine Cancer Using Immunotherapy Combined With Radiation.

Novel therapies combined with radiation continue to be of significant interest in the developmental treatment paradigm of gynecologic cancers. Clinical implementation of immunotherapy in oncology has rapidly changed the treatment landscape, options, paradigm, and outcomes through clinical trials. Immunotherapy has emerged as a therapeutic pillar in the treatment of solid tumors with demonstrable synergistic activity when combined with radiation therapy and chemoradiotherapy by an alteration or enhancement of the immune system. In solid tumors, radiation therapy induces migration of dendritic cells, T cell activation, and proliferation, and increases in tumor-infiltrating lymphocytes. These immunomodulatory effects in conjunction with immune checkpoint blockade are currently under active investigation in the adjuvant, definitive, and metastatic settings. Results from early phase trials demonstrate promising efficacy and overall tolerable toxicity profiles of combined modality treatment. There is significant interest in optimizing the treatment for patients with locally advanced cervical cancer beyond the standard of care-chemoradiation-which has been in place for the last 30 years. The majority of cervical cancer emerges after persistent infection with a high-risk subtype of the human papillomavirus, where viral oncoproteins lead to cellular changes and immortalization. As a result, immune tolerance can develop, resulting in cancer. Knowledge of the mechanism of human papillomavirus-related oncogenesis suggests that immune therapy or checkpoint blockade can reinvigorate an antitumor immune response. Current clinical trials are exploring the therapeutic potential of these approaches. Uterine cancers have been grouped into 4 molecular subclasses by their driver mutations, mutational burden, and copy-number alterations. Of these subgroups, the polymerase epsilon-mutated and microsatellite-unstable may represent up to 40% of endometrial cancers, and they have been shown to be immunogenic. Because of the inherent immunogenicity of these MSI-high tumors, combined immune modulation strategies, including chemotherapy, radiation, and immunotherapy and immune checkpoint inhibitor therapy, are being explored to improve treatment outcomes. In this review, we explore current immunomodulatory and multimodality therapeutic approaches in the treatment of cervical and uterine cancer through ongoing clinical trials investigating the combination of immunotherapy and radiation therapy.

Immune cell composition in the endometrium of patients with a complete molar pregnancy: Effects on outcome.

OBJECTIVE: In 15% of patients with complete hydatidiform mole (CHM), disease progresses to post-molar gestational trophoblastic neoplasia (GTN) after curettage. Tumor infiltrating lymphocytes (TILs) are essential in overcoming disease in many tumors. Infiltrating lymphocyte composition and density may influence trophoblast regression and development of post-molar GTN. We analyzed immune cell composition and density in curettaged endometrium of patients with CHM which spontaneously regressed, and of patients with CHM which progressed to post-molar GTN. METHODS: Sixteen patients with CHM and spontaneous regression, and 16 patients with CHM which progressed to post-molar GTN were selected. Immune cell composition and density of natural killer (NK) cells, natural killer T (NKT)-like cells, Cytotoxic T cells, T-Regulatory and T-Helper cells, were determined by multiplex immunohistochemistry (mIHC). RESULTS: Curettaged endometrium of patients with CHM and spontaneous regression contained a slightly higher number of immune cells compared to patients with CHM which progressed to post-molar GTN. NKT-like cell density was significantly higher in patients with spontaneous regression compared to patients with CHM which progressed to post-molar GTN (483 ± 296 vs.295 ± 143 (mean ± SD), p = 0.03) respectively. NKT-like cell density in the spontaneous regression group was split in 'high' and 'low' (i.e. above and below the median number of NKT-like cells). In patients with high NKT-like cell density, hCG normalized earlier than in patients with low NKT-like cell density (9.5 weeks, (range 3.7-14) vs. 12.9 weeks, (range 8.6-17.9), p = 0.05). CONCLUSION: A high number of NKT-like cells in the endometrium of CHMs may contribute to spontaneous regression of molar trophoblast cells.

Immunogenomic landscape of gynecologic carcinosarcoma.

OBJECTIVE: Carcinosarcoma (CS) of the uterus or ovary is a rare, biphasic tumor comprising epithelial and mesenchymal elements, and exhibits more aggressive clinical features than its carcinoma counterpart. Four molecular subtypes of CS were recently established based on genomic aberration profiles (POLE, MSI, CNH, and CNL) and shown to be associated with multiple clinicopathological parameters, including patient outcomes. However, the role of the immune microenvironment in CS remains unclear. Here, we investigated the influence of the immune cells that infiltrate CS to better understand the immunological status of gynecological CS. METHODS: Tumor immune microenvironmental analyses on CS samples were performed using immune cell profiling with RNA-seq, transcriptomic subtyping with microenvironmental genes, and T-cell receptor repertoire assay. Carcinoma and sarcoma elements from CS samples were also assessed separately. RESULTS: Relying on estimations of tumor-infiltrating cell types from RNA-seq data, POLE and MSI (hypermutator) tumors showed an enrichment of M1 macrophages, plasma cells and CD8+ T cells, whereas CNH and CNL (non-hypermutator) tumors had high levels of M2 macrophages. Further subclassification by immune-related, non-cancer genes identified a fraction of tumors with distinct patient outcomes, particularly those with the CNH genomic aberration subtype. T-cell heterogeneity was independently correlated with prolonged progression-free survival. Differential analysis of carcinoma and sarcoma elements identified many shared mutations but there was little overlap in the T-cell receptor repertoire between the two elements. CONCLUSIONS: Tumor immune microenvironmental analyses could offer potential clinical utility in the stratification of gynecological CS above classification by genomic aberration subtype alone.

The Adaptive and Innate Immune Cell Landscape of Uterine Leiomyosarcomas.

Reactivation of the anti-tumor response has shown substantial progress in aggressive tumors such as melanoma and lung cancer. Data on less common histotypes are scanty. Immune checkpoint inhibitor therapy has been applied to few cases of uterine leiomyosarcomas, of which the immune cell composition was not examined in detail. We analyzed the inflammatory infiltrate of 21 such cases in high-dimensional, single cell phenotyping on routinely processed tissue. T-lymphoid cells displayed a composite phenotype common to all tumors, suggestive of antigen-exposure, acute and chronic exhaustion. To the contrary, myelomonocytic cells had case-specific individual combinations of phenotypes and subsets. We identified five distinct monocyte-macrophage cell types, some not described before, bearing immunosuppressive molecules (TIM3, B7H3, VISTA, PD1, PDL1). Detailed in situ analysis of routinely processed tissue yields comprehensive information about the immune status of sarcomas. The method employed provides equivalent information to extractive single-cell technology, with spatial contexture and a modest investment.

Association between radiotherapy-induced alteration of programmed death ligand 1 and survival in patients with uterine cervical cancer undergoing preoperative radiotherapy.

PURPOSE: To evaluate radiotherapy-induced changes in the expression of programmed death ligand 1 (PD-L1), programmed death 1 (PD-1), and human leukocyte antigen class I (HLA-1) in patients with uterine cervical cancer, as well as infiltration of CD8+ and Forkhead box P3+ (FoxP3+) T lymphocytes into tumor tissue and the prognostic value of these parameters. MATERIALS AND METHODS: We performed immunohistochemical analysis of pre-radiotherapy biopsies and corresponding post-radiotherapy resected tissues in 104 uterine cervical cancer patients undergoing preoperative chemoradiotherapy or radiotherapy alone. We scored the expression of various proteins to distinguish positive from negative samples. RESULTS: PD-L1-expressing tumor cells (PD-L1 TC) increased significantly after chemoradiotherapy (p = 0.043). CD8+ T cell infiltration (p = 0.002) and FoxP3+ T cell infiltration (p = 0.003) decreased significantly after chemoradiotherapy. Expression of PD­1, PD-L1-expressing immune cells (PD-L1 IC), and HLA­1 did not change after chemoradiotherapy. In biopsy specimens obtained before chemoradiotherapy or radiotherapy, greater infiltration of CD8+ T cells (p = 0.001) and FoxP3+ T cells (p = 0.003) were significant predictors of better overall survival (OS). In surgical specimens obtained after chemoradiotherapy or radiotherapy, greater infiltration of PD-L1 TC was the only significant predictor of better OS (p < 0.001) and was related to a significantly lower probability of out-of-field recurrence (p = 0.005). CONCLUSION: Chemoradiotherapy induced an immunologic shift that increased PD-L1 TC. Chemoradiotherapy has immunological effects that can influence the results of treatment for uterine cervical cancer.

Relief of tumor hypoxia unleashes the tumoricidal potential of neutrophils.

Polymorphonuclear neutrophils (PMNs) are increasingly recognized to influence solid tumor development, but why their effects are so context dependent and even frequently divergent remains poorly understood. Using an autochthonous mouse model of uterine cancer and the administration of respiratory hyperoxia as a means to improve tumor oxygenation, we provide in vivo evidence that hypoxia is a potent determinant of tumor-associated PMN phenotypes and direct PMN-tumor cell interactions. Upon relief of tumor hypoxia, PMNs were recruited less intensely to the tumor-bearing uterus, but the recruited cells much more effectively killed tumor cells, an activity our data moreover suggested was mediated via their production of NADPH oxidase-derived reactive oxygen species and MMP-9. Simultaneously, their ability to promote tumor cell proliferation, which appeared to be mediated via their production of neutrophil elastase, was rendered less effective. Relieving tumor hypoxia thus greatly improved net PMN-dependent tumor control, leading to a massive reduction in tumor burden. Remarkably, this outcome was T cell independent. Together, these findings identify key hypoxia-regulated molecular mechanisms through which PMNs directly induce tumor cell death and proliferation in vivo and suggest that the contrasting properties of PMNs in different tumor settings may in part reflect the effects of hypoxia on direct PMN-tumor cell interactions.

In vitro and in vivo activity of sacituzumab govitecan, an antibody-drug conjugate targeting trophoblast cell-surface antigen 2 (Trop-2) in uterine serous carcinoma.

OBJECTIVE: Uterine serous carcinoma (USC) is an aggressive variant of endometrial cancer with poor prognosis. Sacituzumab govitecan (SG) is a novel antibody-drug-conjugate (ADC) targeting trophoblast cell-surface antigen 2 (Trop-2), a transmembrane-calcium-signal-transducer, to deliver SN-38, the active metabolite of irinotecan. The objective of this study was to evaluate the expression of Trop-2 in USC and the preclinical activity of SG against primary USC cell-lines and xenografts. METHODS: We used immunohistochemistry (IHC) and flow-cytometry-based assays to evaluate Trop-2 expression and cell-viability in USC tissue and primary tumor-cell-lines after exposure to SG, non-targeting control ADC, and naked antibody hRS7-IgG. Antibody-dependent-cell-cytotoxicity (ADCC) against Trop-2+ and Trop-2- USC cell-lines was evaluated in vitro using 4-hr-Chromium-release-assays. In vivo activity of SG was tested against Trop-2+ USC xenografts by intravenous administration of SG, control ADC, and hRS7. RESULTS: Trop-2 expression by IHC was detected in 95.1% of USC samples (99/104). Primary tumor cell-lines overexpressing Trop-2 were significantly more sensitive to SG when compared to control ADC (p <0.05). Both SG and hRS7 mediated ADCC in Trop2+ USC cell-lines while no cytotoxicity was detected against Trop-2- cells. SG induced significant bystander killing of Trop-2- tumors when admixed with Trop-2+ tumors. SG caused growth-inhibition and increased survival in SG treated mice harboring Trop-2+ xenografts when compared to controls (p <0.05). CONCLUSIONS: SG is remarkably active against USC overexpressing Trop-2 in vitro and in vivo. Our results combined with SG clinical responses recently reported against multiple chemotherapy resistant human tumors further support clinical development of SG in USC patients with advanced/recurrent disease.

Alteration of tumor associated neutrophils by PIK3CA expression in endometrial carcinoma from TCGA data.

Uterine corpus endometrial carcinoma (UCEC) is one of the most common cancer in female worldwide. PIK3CA has been proven to be a strong prognostic biomarker in UCEC. Nevertheless, current studies have not investigated what effects PIK3CA had on tumor associated neutrophils (TANss). Kaplan-Meier methods were used to compute the survival time of TCGA UCEC patients. GO and KEGG enrichment analysis unveiled relevant pathways PIK3CA affected using DEGs between PIK3CA high expression group and PIK3CA low expression group in TCGA UCEC, as well as GSEA. immune infiltration status was calculated using TIMER. We found that PIK3CA influenced a number of pathways including immune related pathways. The fraction of TANs was certainly altered by PIK3CA expression in UCEC. Our findings suggest that PIK3CA expression may play an important role in tumor immune microenvironment and could alter fraction of TANs in UCEC.

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.

Computational KIR copy number discovery reveals interaction between inhibitory receptor burden and survival.

Natural killer (NK) cells have increasingly become a target of interest for immunotherapies. NK cells express killer immunoglobulin-like receptors (KIRs), which play a vital role in immune response to tumors by detecting cellular abnormalities. The genomic region encoding the 16 KIR genes displays high polymorphic variability in human populations, making it difficult to resolve individual genotypes based on next generation sequencing data. As a result, the impact of polymorphic KIR variation on cancer phenotypes has been understudied. Currently, labor-intensive, experimental techniques are used to determine an individual's KIR gene copy number profile. Here, we develop an algorithm to determine the germline copy number of KIR genes from whole exome sequencing data and apply it to a cohort of nearly 5000 cancer patients. We use a k-mer based approach to capture sequences unique to specific genes, count their occurrences in the set of reads derived from an individual and compare the individual's k-mer distribution to that of the population. Copy number results demonstrate high concordance with population copy number expectations. Our method reveals that the burden of inhibitory KIR genes is associated with survival in two tumor types, highlighting the potential importance of KIR variation in understanding tumor development and response to immunotherapy.