SK-UT-1 uterine leiomyosarcomas (Ut-LMS) cells were transduced with a fatty acid synthase (FASN)-containing retroviral vector to recapitulate the "lipogenic phenotype of cancer." Consistent with this model, forced expression of FASN enhanced SK-UT-1 proliferation, migration, and cellular motion. Further investigation showed FASN promotes trimethylation of H3K9 (H3K9me3) and acetylation of H3K27 (H3K27ac) in SK-UT-1 cells. In contrast, siRNA targeting of FASN in high endogenous FASN expressing SK-LMS-1 Ut-LMS cells inhibits trimethylation of H3K9 and acetylation of H3K27. Palmitate, the predominant fatty acid product of FASN, increased H3K9me3, H3K27ac and H3K27me3 detection in SK-UT-1 cells. FASN promoted histone 3 methylation and acetylation through alteration of histone 3-modifying enzymatic activities (HDAC, HDM, HMT and HAT). ChIP-seq in SK-UT-1-FASN cells with anti-H3K9me3 antibody identified regions of enriched binding compared to vector-only cells. One differentially-enriched gene, CRISP1, was investigated further by ChIP-PCR. The transcriptionally repressive function of H3K9me3 was confirmed in CRISP1. Our results provide mechanistic insight into the pathobiology of the "lipogenic phenotype of cancer." Here, FASN reprograms the Ut-LMS epigenome through chromatin remodeling to promote the "malignant phenotype."

Background

Histologic distinction between well differentiated hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions is a known challenge. Existing biomarkers are of limited diagnostic value. Our previous studies observed an enhanced canalicular expression pattern of clusterin (CLU) in HCC, which was not observed in benign hepatocellular mass lesions such as hepatocellular adenoma. The aim of this study was to further investigate its diagnostic value for HCC by examining the expression pattern of CLU in a large number of non-hepatocellular tumors, and by comparing it with two other commonly used hepatocellular markers pCEA and CD10 that also show a canalicular staining pattern in HCC.

Methods

Enhanced canalicular staining patterns of CLU, pCEA and CD10 were analyzed on 54 surgically resected well to moderately differentiated HCCs on whole tissue sections, of which 37 had surrounding regenerative nodules while the remaining 17 had a non-cirrhotic background. CLU immunostaining was also performed on tissue microarray sections that contained 74 HCCs (40 of which were also stained for pCEA and CD10), 55 normal liver tissue samples, and 1305 non-hepatocellular tumors from multiple organs.

Results

Enhanced CLU canalicular staining was observed in 70% (89/128) HCCs but not in regenerative nodules, normal liver tissues or any non-hepatocellular tumors. The sensitivity and specificity for enhanced canalicular staining pattern of CLU in HCCs were 0.70 and 1.00. This enhanced canalicular pattern was observed in only 26 and 23% HCCs for CD10 and pCEA, respectively. These results further demonstrate that the distinctive enhanced canalicular pattern of CLU is unique to HCC.

Conclusions

CLU is superior to pCEA and CD10 as a diagnostic immunomarker in that it can help distinguish well to moderately differentiated HCC not only from non-HCC malignancies but also from benign hepatocellular mass lesions.

Background and objectives

Primary liver sarcomas (PLS) are rare. Published series are limited by small numbers of patients.

Methods

We reviewed the National Cancer Database (2004-2014) for patients who underwent surgical resection of PLS.

Results

Of 237 patients identified, the majority were female (60.8%), with median age of 52 years. Histologies were: epithelioid hemangioendothelioma (n = 67), angiosarcoma (n = 64), leiomyosarcoma (n = 33), embryonal rhabdomyosarcoma (n = 31), carcinosarcoma (n = 16), giant cell sarcoma (n = 14), spindle cell sarcoma (n = 12). Ninety-seven (40.9%) patients underwent lobectomies or extended lobectomies, 41 patients (17.3%) underwent transplantation. Surgical margins were negative in 82.9%. Tumors were well differentiated in 11.3%. Histology type correlated with outcome with the best prognosis for epithelioid hemangioendothelioma (OS: not reached, similar for resection and transplantation) and the worst for angiosarcoma (OS:16.6 mo with resection; 6 mo with transplantation; P = 0.04). Resections with microscopically negative margins were associated with improved survival (58.7 vs 11.3 mo for positive margins; P < 0.001). Chemotherapy and radiation therapy were used in a minority of patients (32.9% and 4.3% respectively) with no improvement in outcomes.

Conclusions

Both hepatic resection and liver transplantation can be associated with long term survival for selected primary liver sarcomas such as epitheliod hemangioendotheliomas. Histology type and the ability to resect the tumor with negative margins correlate with outcomes and the decision to operate should be carefully weighed for subtypes with particularly dismal prognosis such as angiosarcomas.

Mitochondria are dynamic organelles that constantly fuse and divide, forming dynamic tubular networks. Abnormalities in mitochondrial dynamics and morphology are linked to diverse pathological states, including cancer. Thus, alterations in mitochondrial parameters could indicate early events of disease manifestation or progression. However, finding reliable and quantitative tools for monitoring mitochondria and determining the network parameters, particularly in live cells, has proven challenging. Here, we present a 2D confocal imaging-based approach that combines automatic mitochondrial morphology and dynamics analysis with fractal analysis in live small cell lung cancer (SCLC) cells. We chose SCLC cells as a test case since they typically have very little cytoplasm, but an abundance of smaller mitochondria compared to many of the commonly used cell types. The 2D confocal images provide a robust approach to quantitatively measure mitochondrial dynamics and morphology in live cells. Furthermore, we performed 3D reconstruction of electron microscopic images and show that the 3D reconstruction of the electron microscopic images complements this approach to yield better resolution. The data also suggest that the parameters of mitochondrial dynamics and fractal dimensions are sensitive indicators of cellular response to subtle perturbations, and hence, may serve as potential markers of drug response in lung cancer.

Oncogenic (mutant) Ras protein Kirsten rat sarcoma viral oncogene homolog (KRAS) promotes uncontrolled proliferation, altered metabolism, and loss of genome integrity in a cell-intrinsic manner. Here, we demonstrate that CD4⁺ T cells when incubated with tumor-derived exosomes from mutant (MT) KRAS non-small-cell lung cancer (NSCLC) cells, patient sera, or a mouse xenograft model, induce phenotypic conversion to FOXP3⁺ Treg-like cells that are immune-suppressive. Furthermore, transfecting T cells with MT KRAS cDNA alone induced phenotypic switching and mathematical modeling supported this conclusion. Single-cell sequencing identified the interferon pathway as the mechanism underlying the phenotypic switch. These observations highlight a novel cytokine-independent, cell-extrinsic role for KRAS in T cell phenotypic switching. Thus, targeting this new class of Tregs represents a unique therapeutic approach for NSCLC. Since KRAS is the most frequently mutated oncogene in a wide variety of cancers, the findings of this investigation are likely to be of broad interest and have a large scientific impact.

Purpose: Preoperative or neoadjuvant therapy (NT) is increasingly used in patients with locally advanced or inflammatory breast cancer to allow optimal surgery and aim for pathologic response. However, many breast cancers are resistant or relapse after treatment. Here, we investigated conjunctive chemotherapy-triggered events occurring systemically and locally, potentially promoting a cancer stem-like cell (CSC) phenotype and contributing to tumor relapse.Experimental Design: We started by comparing the effect of paired pre- and post-NT patient sera on the CSC properties of breast cancer cells. Using cell lines, patient-derived xenograft models, and primary tumors, we investigated the regulation of CSCs and tumor progression by chemotherapy-induced factors.Results: In human patients and mice, we detected a therapy-induced CSC-stimulatory activity in serum, which was attributed to therapy-associated monocytosis leading to systemic elevation of monocyte chemoattractant proteins (MCP). The post-NT hematopoietic regeneration in the bone marrow highlighted both altered monocyte-macrophage differentiation and biased commitment of stimulated hematopoietic stem cells toward monocytosis. Chemotherapeutic agents also induce monocyte expression of MCPs through a JNK-dependent mechanism. Genetic and pharmacologic inhibitions of the MCP-CCR2 pathway blocked chemotherapy's adverse effect on CSCs. Levels of nuclear Notch and ALDH1 were significantly elevated in primary breast cancers following NT, whereas higher levels of CCR2 in pre-NT tumors were associated with a poor response to NT.Conclusions: Our data establish a mechanism of chemotherapy-induced cancer stemness by linking the cellular events in the bone marrow and tumors, and suggest pharmacologic inhibition of CCR2 as a potential cotreatment during conventional chemotherapy in neoadjuvant and adjuvant settings. Clin Cancer Res; 24(10); 2370-82. ©2018 AACR.

Cancer-secreted microRNAs (miRNAs) are emerging mediators of cancer-host crosstalk. Here we show that miR-105, which is characteristically expressed and secreted by metastatic breast cancer cells, is a potent regulator of migration through targeting the tight junction protein ZO-1. In endothelial monolayers, exosome-mediated transfer of cancer-secreted miR-105 efficiently destroys tight junctions and the integrity of these natural barriers against metastasis. Overexpression of miR-105 in nonmetastatic cancer cells induces metastasis and vascular permeability in distant organs, whereas inhibition of miR-105 in highly metastatic tumors alleviates these effects. miR-105 can be detected in the circulation at the premetastatic stage, and its levels in the blood and tumor are associated with ZO-1 expression and metastatic progression in early-stage breast cancer.

SUMMARYCancer-secreted miRNAs are emerging mediators of cancer–host crosstalk. Here we show that miR-105, which is characteristically expressed and secreted by metastatic breast cancer cells, is a potent regulator of migration through targeting the tight junction protein ZO-1. In endothelial monolayers, exosome-mediated transfer of cancer-secreted miR-105 efficiently destroys tight junctions and the integrity of these natural barriers against metastasis. Overexpression of miR-105 in non-metastatic cancer cells induces metastasis and vascular permeability in distant organs, whereas inhibition of miR-105 in highly metastatic tumors alleviates these effects. MiR-105 can be detected in the circulation at the pre-metastatic stage, and its levels in the blood and tumor are associated with ZO-1 expression and metastatic progression in early-stage breast cancer.

Ewing sarcoma (EWS) is an aggressive bone malignancy that mainly affects children and young adults. The mechanisms by which EWS (EWSR1) fusion genes drive the disease are not fully understood. CRM1 (XPO1) traffics proteins from the nucleus, including tumor suppressors and growth factors, and is overexpressed in many cancers. A small-molecule inhibitor of CRM1, KPT-330, has shown therapeutic promise, but has yet to be investigated in the context of EWS. In this study, we demonstrate that CRM1 is also highly expressed in EWS. shRNA-mediated or pharmacologic inhibition of CRM1 in EWS cells dramatically decreased cell growth while inducing apoptosis, cell-cycle arrest, and protein expression alterations to several cancer-related factors. Interestingly, silencing of CRM1 markedly reduced EWS-FLI1 fusion protein expression at the posttranscriptional level and upregulated the expression of the well-established EWS-FLI1 target gene, insulin-like growth factor binding protein 3 (IGFBP3), which inhibits IGF-1. Accordingly, KPT-330 treatment attenuated IGF-1-induced activation of the IGF-1R/AKT pathway. Furthermore, knockdown of IGFBP3 increased cell growth and rescued the inhibitory effects on IGF-1 signaling triggered by CRM1 inhibition. Finally, treatment of EWS cells with a combination of KPT-330 and the IGF-1R inhibitor, linsitinib, synergistically decreased cell proliferation both in vitro and in vivo Taken together, these findings provide a strong rationale for investigating the efficacy of combinatorial inhibition of CRM1 and IGF-1R for the treatment of EWS. Cancer Res; 76(9); 2687-97. ©2016 AACR.