Infiltrating CD8+ T cells and M2 macrophages are retained in tumor matrix tracks enriched in low tension fibronectin fibers.

Tracks rich in matrix and cells, as described in several cancer types, have immunosuppressive functions and separate tumor nests and stroma, yet their origin is unknown. Immunostainings of cryosections from mouse breast tumors show that these tracks are bordered by an endothelial-like basement membrane, filled with fibers of collagen adjacent to tenascin-C (TNC) and low-tension fibronectin (Fn) fibers. While present in early-stage tumors and maturing with time, tracks still form under TNC KO conditions, however, host (not tumor cell)-derived TNC is important for track maturation. Tumor infiltrating leukocytes (mostly M2 macrophages and CD8+ T cells) are retained in tracks of early-stage tumors. Following track maturation, retained tumor infiltrating leukocyte (TIL) numbers get reduced and more CD8+ TIL enter the tumor nests in the absence of TNC. As these tracks are enriched with platelets and fibrinogen and have a demarcating endothelial-like basement membrane often adjacent to endothelial cells, this suggests a role of blood vessels in the formation of these tracks. The Fn fiber tension probe FnBPA5 colocalizes with TNC and immune cells in the tracks and shows decreased binding in tracks lacking TNC. Consequently, FnBPA5 can serve as probe for tumor matrix tracks that have immune suppressive properties.

Advances on the roles of tenascin-C in cancer.

The roles of the extracellular matrix molecule tenascin-C (TNC) in health and disease have been extensively reviewed since its discovery over 40 years ago. Here, we will describe recent insights into the roles of TNC in tumorigenesis, angiogenesis, immunity and metastasis. In addition to high levels of expression in tumors, and during chronic inflammation, and bacterial and viral infection, TNC is also expressed in lymphoid organs. This supports potential roles for TNC in immunity control. Advances using murine models with engineered TNC levels were instrumental in the discovery of important functions of TNC as a danger-associated molecular pattern (DAMP) molecule in tissue repair and revealed multiple TNC actions in tumor progression. TNC acts through distinct mechanisms on many different cell types with immune cells coming into focus as important targets of TNC in cancer. We will describe how this knowledge could be exploited for cancer disease management, in particular for immune (checkpoint) therapies.

Modulating tenascin-C functions by targeting the MAtrix REgulating MOtif, "MAREMO".

The extracellular matrix molecule Tenascin-C (TNC) promotes cancer and chronic inflammation by multiple mechanisms. Recently, TNC was shown to promote an immune suppressive tumor microenvironment (TME) through binding soluble chemoattracting factors, thus retaining leukocytes in the stroma. TNC also binds to fibronectin (FN) and other molecules, raising the question of a potential common TNC binding mechanism. By sequence comparison of two TNC-interacting domains in FN, the fifth (FN5) and thirteenth (FN13) fibronectin type III domains we identified a MAtrix REgulating MOtif "MAREMO" or M-motif that is highly conserved amongst vertebrates. By sequence analysis, structural modeling and functional analysis we found also putative M-motifs in TNC itself. We showed by negative staining electron microscopic imaging that the M-motif in FN mediates interactions with FN as well as with TNC. We generated two M-motif mimetic peptides P5 and P13 resembling the M-motif in FN5 and FN13, respectively. By using structural information we modelled binding of these M-motif mimetics revealing a putative MAREMO binding site MBS in FN5 and TN3, respectively overlapping with the M-motif. We further demonstrated that the M-motif mimetic peptides blocked several functions of TNC, such as binding of TNC to FN, cell rounding on a mixed FN/TNC substratum, FN matrix expression and subsequent assembly, TNC-induced signaling and gene expression, TNC chemokine binding and dendritic cell retention, thus providing novel opportunities to inhibit TNC actions. Our results suggest that targeting the MAREMO/MBS interaction could be exploited for reducing inflammation and matrix functions in cancer and fibrosis.

Impact of Tenascin-C on Radiotherapy in a Novel Syngeneic Oral Squamous Cell Carcinoma Model With Spontaneous Dissemination to the Lymph Nodes.

Radiotherapy, the most frequent treatment of oral squamous cell carcinomas (OSCC) besides surgery is employed to kill tumor cells but, radiotherapy may also promote tumor relapse where the immune-suppressive tumor microenvironment (TME) could be instrumental. We established a novel syngeneic grafting model from a carcinogen-induced tongue tumor, OSCC13, to address the impact of radiotherapy on OSCC. This model revealed similarities with human OSCC, recapitulating carcinogen-induced mutations found in smoking associated human tongue tumors, abundant tumor infiltrating leukocytes (TIL) and, spontaneous tumor cell dissemination to the local lymph nodes. Cultured OSCC13 cells and OSCC13-derived tongue tumors were sensitive to irradiation. At the chosen dose of 2 Gy mimicking treatment of human OSCC patients not all tumor cells were killed allowing to investigate effects on the TME. By investigating expression of the extracellular matrix molecule tenascin-C (TNC), an indicator of an immune suppressive TME, we observed high local TNC expression and TIL infiltration in the irradiated tumors. In a TNC knockout host the TME appeared less immune suppressive with a tendency towards more tumor regression than in WT conditions. Altogether, our novel syngeneic tongue OSCC grafting model, sharing important features with the human OSCC disease could be relevant for future anti-cancer targeting of OSCC by radiotherapy and other therapeutic approaches.

Prognostic and predictive value of an immune infiltration signature in diffuse lower-grade gliomas.

BACKGROUNDLower-grade gliomas (LGGs) vary widely in terms of the patient's overall survival (OS). There is no current, valid method that could exactly predict the survival. The effects of intratumoral immune infiltration on clinical outcome have been widely reported. Thus, we aim to develop an immune infiltration signature to predict the survival of LGG patients.METHODSWe analyzed 1216 LGGs from 5 public data sets, including 2 RNA sequencing data sets and 3 microarray data sets. Least absolute shrinkage and selection operator (LASSO) Cox regression was used to select an immune infiltration signature and build a risk score. The performance of the risk score was assessed in the training set (329 patients), internal validation set (140 patients), and 4 external validation sets (405, 118, 88, and 136 patients).RESULTSAn immune infiltration signature consisting of 20 immune metagenes was used to generate a risk score. The performance of the risk score was thoroughly verified in the training and validation sets. Additionally, we found that the risk score was positively correlated with the expression levels of TGF-ß and PD-L1, which were important targets of combination immunotherapy. Furthermore, a nomogram incorporating the risk score, patient's age, and tumor grade was developed to predict the OS, and it performed well in all the training and validation sets (C-index: 0.873, 0.881, 0.781, 0.765, 0.721, and 0.753).CONCLUSIONThe risk score based on the immune infiltration signature has reliable prognostic and predictive value for patients with LGGs and is a potential biomarker for the cotargeting immunotherapy.FUNDINGThis work was supported by The National Natural Science Foundation of China (grant nos. 81472370 and 81672506), the Natural Science Foundation of Beijing (grant no. J180005), the National High Technology Research and Development Program of China (863 Program, grant no. 2014AA020610), and the National Basic Research Program of China (973 Program, grant no. 2014CB542006).

MicroRNA-195 Functions as a Tumor Suppressor by Directly Targeting Fatty Acid Synthase in Malignant Meningioma.

OBJECTIVE: Meningiomas are among the most common primary intracranial tumors. Up to 20% of cases will show increased malignancy at histological examination (World Health Organization grade II or III). Effective pharmacotherapy, except for radiotherapy, is lacking. Therefore, it is necessary to study the pathogenesis of malignant meningioma to provide more treatment strategies. METHODS: RNA sequencing and micro-RNA (miRNA) microarray detection were applied to identify differentially expressed messenger RNAs (mRNAs) and miRNAs in benign and malignant meningioma. The miRDB and TargetScan databases were used to predict the potential interaction between miRNAs and mRNAs. A proliferation assay was used to evaluate the cell growth. A wound healing assay and Transwell assay were performed to assess the cell migration and invasion abilities, respectively. The interaction between miRNA and mRNA was identified using a luciferase reporter assay. RESULTS: We found fatty acid synthase (FASN) was significantly upregulated in malignant meningioma compared with benign meningioma. Knockdown of FASN significantly inhibited proliferation, migration, and invasion of IOMM-Lee cells. Moreover, miR-195 was verified to directly target FASN using a luciferase reporter assay. Upregulation of miR-195 also significantly inhibited proliferation, migration, and invasion of IOMM-Lee cells. Furthermore, we performed bioinformatics analysis to predict the competing endogenous RNAs (ceRNAs) and found that NUP210, SPIRE2, SLC7A1, and DMTN might function as ceRNAs of FASN by sponging miR-195 in meningioma. CONCLUSIONS: Our results have suggested a tumor suppressive role for miR-195 in the tumorigenesis and progression of malignant meningioma by targeting FASN. In addition, NUP210, SPIRE2, SLC7A1, and DMTN might act as ceRNAs to regulate FASN expression by sponging miR-195.

Primary intracranial malignant melanoma: proposed treatment protocol and overall survival in a single-institution series of 15 cases combined with 100 cases from the literature.

OBJECTIVE: The overall survival and pertinent adverse factors for primary intracranial malignant melanoma (PIMM) have not been previously determined. This aim of this study was to determine the rates of progression-free survival (PFS) and overall survival (OS) and identify the adverse factors for PIMM. METHODS: This study included 15 cases from the authors' own series and 100 cases with detailed clinical data that were obtained from the literature from 1914 to 2018 using the Ovid Medline, EMBASE, PubMed, Cochrane, and EBSCO databases. Patient demographics, treatment (surgery, chemotherapy, and radiotherapy [RT]), PFS, and OS were reviewed. Data from prior publications were processed and used according to PRISMA guidelines. RESULTS: Diffuse lesions were identified in 24 (20.9%) patients, who had a younger age (p < 0.001). The mean follow-up time was 16.6 months, and 76 (66.1%) deaths occurred. The 6-month, 1-year, 3-year, and 5-year OS rates of the whole cohort were 62.8%, 49.9%, 28.9%, and 17.2%, respectively, with an estimated median survival time (EMST) of 12.0 months. The multivariate analysis revealed that gross-total resection (GTR) (HR 0.299, 95% CI 0.180-0.497, p < 0.001), radiotherapy (HR 0.577, 95% CI 0.359-0.929, p = 0.024), and chemotherapy (HR 0.420, 95% CI 0.240-0.735, p = 0.002) predicted a better OS. The EMST was 5.0 months in patients with diffuse-type PIMM and 13.0 months in patients with the solitary type. Patients receiving GTR with adjuvant RT and/or chemotherapy (GTR + [RT and/or chemo]) had significantly higher 1-year and 5-year OS rates (73.0% and 40.1%, respectively) and a longer EMST (53 months) than patients who underwent GTR alone (20.5 months) or RT and/or chemotherapy without GTR (13.0 months). CONCLUSIONS: Optimal outcomes could be achieved by radical resection plus postoperative radiotherapy and/or chemotherapy. Patients with diffuse PIMM have a more severe clinical spectrum and poorer survival than patients with solitary PIMM. Immunotherapy and targeted therapy show promise as treatment options for PIMM based on results in patients with brain metastases from extracranial melanoma.

Management and outcomes of pregnant patients with central nervous system hemangioblastoma.

The study aims to assess the management and maternal and fetal outcomes of pregnancies complicated by central nervous system (CNS) hemangioblastoma. Twenty-four female patients with CNS hemangioblastoma, who were pregnant in a tumor-burden status, were identified. Their medical charts, treatments, and follow-up materials were carefully reviewed. Of the included 24 CNS patients with hemangioblastoma (14 intracranial and 10 spinal hemangioblastomas), 5 patients (20.8%) were diagnosed with Von Hippel-Lindau disease (VHL). The median age of these patients at admission was 27.5 years. Intracranial hypertension was a common presenting symptom for patients with intracranial hemangioblastoma and was observed in 85.7% (12/14) of cases; the other 10 patients with spinal hemangioblastomas all suffered from paresthesia. Overall, 66.7% (16/24) of patients with CNS hemangioblastoma went through the gestational course with conventional observation; 16.6% (4/24) of patients accepted a ventriculo-peritoneal shunt (VPS) to delay the tumor resection; and 16.7% (4/24) of patients needed urgent tumor resection even when symptomatic treatments were given. Variable symptom improvement was seen when patients had follow-up visits at a median of 32.5 months. No maternal death or tumor recurrence was identified. For the fetal prognoses, one (4.2%) pregnancy ended in a spontaneous miscarriage and for (16.7%) pregnancies were interrupted; the other 19 (79.2%) live births were in good status without any congenital malformations. Symptomatic treatment was the first choice for pregnant patients with CNS hemangioblastoma. When needed, urgent tumor resection could be safely achieved with careful maternal and fetal monitoring. Both maternal and fetal prognoses were favorable during follow-up.

Prognostic Factors, Survival, and Treatment for Intracranial World Health Organization Grade II Chordoid Meningiomas and Clear-Cell Meningiomas.

OBJECTIVE: Chordoid meningioma (CM) and clear-cell meningioma (CCM) are rare World Health Organization grade II meningioma subtypes. This study aimed to evaluate favorable factors and appropriate therapeutic strategies for these lesions. METHODS: We retrospectively reviewed clinical data from 111 cases of grade II meningiomas, including 55 cases of CM and 56 cases of CCM, between January 2011 and December 2015. RESULTS: The mean follow-up time of the rare World Health Organization grade II meningiomas (n = 111) was 45.3 months. In the CM group, 8 patients (14.5%) experienced recurrence, and 2 patients (3.6%) died. In the CCM group, 22 patients (39.3%) experienced recurrence, and 9 patients (16.1%) died. Significant differences were observed between the CM and CCM groups in tumor size (P = 0.019), history of surgery (P = 0.038), and peritumoral edema (P = 0.004). In the CM group, gross total resection was associated with favorable progression-free survival (hazard ratio, 0.144; 95% confidence interval, 0.029-0.714; P = 0.018). In the CCM group, univariate analyses showed that preoperative Karnofsky Performance Status <80 (P < 0.001), tumor size ≥5 cm (P = 0.015), tumor size (per-centimeter increase) (P = 0.022), bone invasion (P = 0.004), a history of surgery (P < 0.001), and subtotal resection (P = 0.009) were associated with worse progression-free survival. Male gender (P = 0.039), tumor size (per-centimeter increase) (P = 0.043), bone invasion (P = 0.030), and a history of surgery (P = 0.007) were associated with poor overall survival. CONCLUSIONS: This study showed that gross total resection should be achieved in grade II meningiomas. Patients with larger tumors and/or surgical histories had worse outcomes.

Primary Intracranial Angioleiomyomas as Rare, Nonmalignant, and Distinct Neoplastic Entities: A Series of 8 Cases and a Literature Review.

OBJECTIVE: Primary intracranial angioleiomyoma is a rare and distinct neoplasm. Only 29 cases have been reported previously, and we aimed to investigate the clinical and radiopathologic features of these lesions. METHODS: Medical records and radiographs of 8 patients (7 male and 1 female; mean age: 48.7 years) at our institution were reviewed retrospectively. Patient follow-up and a literature review were performed. RESULTS: The most common preoperative symptom was a visual defect (n = 2), followed by diplopia (n = 1) and abducens paralysis (n = 1). Three patients were asymptomatic. The parasellar area (particularly the cavernous sinus) was the predilection site (n = 4; 50.0%). Radiographically, all lesions were solid without cystic degeneration. All lesions appeared with T1 hypointensity and T2 hyperintensity, and they were gradually heterogeneously enhanced after the administration of gadolinium. Complete resection was achieved in 7 patients (87.5%) without recurrence after 26.8 months of follow-up. Mitosis was rarely observed, and the Ki-67 labeling index was less than 1%; pathologically, the cavernous type was the most common. CONCLUSIONS: Primary intracranial angioleiomyomas were prevalent in middle-aged men, and they usually involved the cavernous sinus and were frequently pathologically identified as the cavernous type. Preoperative symptoms varied depending on lesion location. The preoperative diagnosis of primary intracranial angioleiomyomas is difficult without pathology. Digital subtraction angiography and preoperative embolization are useful for differential diagnosis and surgery. Given the indolent biology of these tumors, a favorable outcome can be achieved using total resection without recurrence. A larger sample size with long-term follow-up is needed to verify our findings.

World Health Organization Grade III (Nonanaplastic) Meningioma: Experience in a Series of 23 Cases.

OBJECTIVE: Rhabdoid meningioma (RM) and papillary meningioma (PM) are rare variants of World Health Organization grade III meningiomas. In this study, we presented a series of 23 cases from our institution to investigate adverse factors of and appropriate treatment for RM and PM. METHODS: Clinical data from 23 cases of PM and RM between January 2011 and December 2015 were retrospectively reviewed. RESULTS: The median follow-up was 38.0 months for World Health Organization grade III meningiomas. The mean progression-free survival (PFS) was 37.6 months, with 1-year, 3-year, and 5-year PFS of 78.3%, 50.8%, and 43.6%, respectively. The mean overall survival (OS) was 48.8 months, with 1-year, 3-year, and 5-year OS of 95.7%, 82.6%, and 44.0%, respectively. Univariate analysis showed that a ki-67 proliferation index >20% (hazard ratio [HR], 4.190; 95% confidence interval [CI], 1.033-17.001; P = 0.045) and PM (HR, 3.375; 95% CI, 0.998-11.408; P = 0.005) were related to worse PFS. Patients administered postoperative radiotherapy (PRT) after surgery had longer OS than did patients who did not receive PRT (median, 60.7 vs. 35.1 months; P = 0.029). Multivariate analysis showed that PRT was an independent factor for PFS (HR, 0.147; 95% CI, 0.033-0.657; P = 0.012) and OS (HR, 0.130; 95% CI, 0.025-0.691; P = 0.017) and that RM was an independent factor for PFS (HR, 7.312; 95% CI, 1.587-33.688; P = 0.011) and OS (HR, 6.447; 95% CI, 1.310-31.740; P = 0.022). CONCLUSIONS: We recommended adjuvant radiation regardless of the extent of resection. Individuals with PM or RM were at increased risk of recurrence and death; appropriate treatment for these patients should be further studied, and close follow-up is needed.