Novel strategies against treatment‐resistant tumor cells remain a challenging but promising therapeutic approach. Despite accumulated evidence suggesting the presence of highly malignant cell ...populations within tumors, the unsolved issues such as in vivo targeting and clinical relevance remain. Here, we report a preclinical trial based on the identified molecular mechanisms underlying osteosarcoma‐initiating cells and their clinical relevance. We identified key microRNAs (miRNAs) that were deregulated in a highly malignant CD133high population and found that miR‐133a regulated the cell invasion that characterizes a lethal tumor phenotype. Silencing of miR‐133a with locked nucleic acid (LNA) reduced cell invasion of this cell population, and systemic administration of LNA along with chemotherapy suppressed lung metastasis and prolonged the survival of osteosarcoma‐bearing mice. Furthermore, in a clinical study, high expression levels of CD133 and miR‐133a were significantly correlated with poor prognosis, whereas high expression levels of the four miR‐133a target genes were correlated with good prognosis. Overall, silencing of miR‐133a with concurrent chemotherapy would represent a novel strategy that targets multiple regulatory pathways associated with metastasis of the malignant cell population within osteosarcoma. Stem Cells 2014;32:959–973
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract only
9044
Background: Programmed death ligand-1 (PD-L1) expression is not a completely reliable predictive marker of the efficacy of anti-programmed cell death protein-1 (PD-1)/anti-PD-L1 ...therapy in advanced non-small cell lung cancer patients (NSCLC). Immune-related tumor microenvironment (TME) is classified into four different types based on the status of tumor-infiltrating lymphocytes (TILs) and PD-L1 expression. Methods: We retrospectively reviewed advanced NSCLC patients treated with anti-PD-1/anti-PD-L1 therapy between 2015 and 2019, and investigated the association between the efficacy of anti-PD-1/anti-PD-L1 therapy, the types of TME based on PD-L1 (clone: 22C3) expression, and the density of CD8-positive TILs by immunohistochemistry (/mm
2
), and mutational profiles assessed by next-generation sequencing. Results: Overall, 228 patients without driver mutation ( EGFR, ALK, ROS1, and RET) were included in the analysis. The patients were classified into four following groups: Type I: PD-L1
High
(tumor proportion score TPS≥50%)/TIL
High
(≥85/mm
2
; n = 73), Type II: PD-L1
Low
(TPS < 50%)/TIL
Low
( < 85/mm
2
; n = 70), Type III: PD-L1
High
/TIL
Low
(n = 37), and Type IV: PD-L1
Low
/TIL
High
(n = 48). The progression-free survival (PFS) and objective response rate (ORR) of anti-PD-1/anti-PD-L1 therapy clearly differed according to the different tumor microenvironment (TME) types (ORR and median PFS; Type I: 64%, 14.5 months, Type II: 12%, 2.1 months, Type III: 24%, 3.6 months, Type IV: 41%, 10.8 months). In patients with PD-L1
High
tumors, Type I tumors had significantly better ORR and PFS than Type III
(ORR: p < 0.001, and PFS: p < 0.001) tumors. Regarding the association between mutational profiles, histology and the TME types, the presence of TP53 mutation and KRAS mutation significantly related to TIL
High
(Type I and IV) and PD-L1
High
tumors (Type I and III), respectively. Pleomorphic and NSCLC- not otherwise specified histology were associated with Type I tumors, while LCNEC was associated with PD-L1 low tumors (Type II and IV). Conclusions: Various factors (mutational profile and histology) are related to TME classification based on the status of TILs and PD-L1 expression. Differential types of TME, including PD-L1 expression and TILs status, can accurately predict the efficacy of anti-PD-1/anti-PD-L1 therapy.Table: see text
Aims
Extraskeletal osteosarcoma (ESOS) is a sarcoma in the non‐skeletal tissue that directly produces neoplastic osteoid or bone. De‐differentiated liposarcoma (DDLPS) and malignant peripheral nerve ...sheath tumour (MPNST) are the two most common types of sarcoma that can harbour heterologous osteosarcomatous differentiation. We aimed to determine the potential relationship of ESOS to DDLPS and MPNST.
Methods and results
We investigated MDM2 and H3K27me3 status in 19 cases of ESOS, two of which contained a low‐grade component. The ESOS affected deep soft tissues (n = 10), superficial soft tissues (n = 3) and organs (n = 6). Among 10 deep soft‐tissue ESOS, six showed MDM2 amplification, four of which also harboured CDK4 co‐amplification. Both ESOS with a low‐grade component showed co‐amplification for MDM2 and CDK4. Among the six organ‐based ESOS three giant cell‐rich ESOS showed an H3K27me3 deficiency (one in primary and two in metastatic sites). Using targeted next generation sequencing, an H3K27me3‐deficient ESOS showed EED homozygous deletion, while none of the three showed alterations in NF1, CDKN2A or SUZ12 genes. During median follow‐up of 20 months, all six patients with MDM2‐amplified ESOS lived for 3–103 months, while two of the three patients with H3K27me3‐deficient ESOS died from this disease in 4 and 20 months, respectively.
Conclusion
We demonstrate that ESOS may include at least two small subsets: an MDM2‐amplified deep soft‐tissue ESOS (which may be related to DDLPS) and an H3K27me3‐deficient organ‐based ESOS (which is probably unrelated to MPNST). Larger studies are required to validate the present observations and investigate the clinical implications of such subcategorisation.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
In soft tissue sarcomas, the diagnosis of malignant fibrous histiocytoma (MFH) has been a very controversial issue, and MFH is now considered to be reclassified into pleomorphic subtypes of other ...sarcomas. To characterize MFH genetically, we used an oligonucleotide microarray to analyze gene expression in 105 samples from 10 types of soft tissue tumors. Spindle cell and pleomorphic sarcomas, such as dedifferentiated liposarcoma, myxofibrosarcoma, leiomyosarcoma, malignant peripheral nerve sheath tumor (MPNST), fibrosarcoma and MFH, showed similar gene expression patterns compared to other tumors. Samples from those five sarcoma types could be classified into respective clusters based on gene expression by excluding MFH samples. We calculated distances between MFH samples and other five sarcoma types (dedifferentiated liposarcoma, myxofibrosarcoma, leiomyosarcoma, MPNST and fibrosarcoma) based on differentially expressed genes and evaluated similarities. Three of the 21 MFH samples showed marked similarities to one of the five sarcoma types, which were supported by histological findings. Although most of the remaining 18 MFH samples showed little or no histological resemblance to one of the five sarcoma types, 12 of them showed moderate similarities in terms of gene expression. These results explain the heterogeneity of MFH and show that the majority of MFHs could be reclassified into pleomorphic subtypes of other sarcomas. Taken together, gene expression profiling could be a useful tool to unveil the difference in the underlying molecular backgrounds, which leads to a rational taxonomy and diagnosis of a diverse group of soft tissue sarcomas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Granular cell tumors (GCTs) are rare mesenchymal tumors that exhibit a characteristic morphology and a finely granular cytoplasm. The genetic alterations responsible for GCT tumorigenesis had been ...unknown until recently, when loss‐of‐function mutations of ATP6AP1 and ATP6AP2 were described. Thus, we performed whole‐exome sequencing, RNA sequencing, and targeted sequencing of 51 GCT samples. From these genomic analyses, we identified mutations in genes encoding vacuolar H+‐ATPase (V‐ATPase) components, including ATP6AP1 and ATP6AP2, in 33 (65%) GCTs. ATP6AP1 and ATP6AP2 mutations were found in 23 (45%) and 2 (4%) samples, respectively, and all were truncating or splice site mutations. In addition, seven other genes encoding V‐ATPase components were also mutated, and three mutations in ATP6V0C occurred on the same amino acid (isoleucine 136). These V‐ATPase component gene mutations were mutually exclusive, with one exception. These results suggest that V‐ATPase function is impaired in GCTs not only by loss‐of‐function mutations of ATP6AP1 and ATP6AP2 but also through mutations of other subunits. Our findings provide additional support for the hypothesis that V‐ATPase dysfunction promotes GCT tumorigenesis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Oral conditions are relatively common in patients with inflammatory bowel disease (IBD). However, the contribution of oral maladies to gut inflammation remains unexplored. Here, we investigated the ...effect of periodontitis on disease phenotypes of patients with IBD. In all, 60 patients with IBD (42 with ulcerative colitis UC and 18 with Crohn's disease CD) and 45 healthy controls (HCs) without IBD were recruited for this clinical investigation. The effects of incipient periodontitis on the oral and gut microbiome as well as IBD characteristics were examined. In addition, patients were prospectively monitored for up to 12 months after enrollment. We found that, in both patients with UC and those with CD, the gut microbiome was significantly more similar to the oral microbiome than in HCs, suggesting that ectopic gut colonization by oral bacteria is increased in patients with IBD. Incipient periodontitis did not further enhance gut colonization by oral bacteria. The presence of incipient periodontitis did not significantly affect the clinical outcomes of patients with UC and CD. However, the short CD activity index increased in patients with CD with incipient periodontitis but declined or was unchanged during the study period in patients without periodontitis. Thus, early periodontitis may associate with worse clinically symptoms in some patients with CD.
Oncogenic RET fusion, caused by an inversion in chromosome 10, was recently identified as a driver mutation for the development of lung adenocarcinoma (LADC). Nevertheless, the molecular mechanism(s) ...underlying the rearrangement of the RET locus during lung carcinogenesis are unknown.
Genomic segments containing breakpoint junctions for RET fusions were cloned and analyzed by genomic polymerase chain reaction and genome capture sequencing using a next-generation sequencer to identify the mechanisms involved in DNA strand breaks and illegitimate joining of DNA ends. Of the 18 cases studied, 16 were identified by screening 671 LADC cases and two were previously published.
Almost all (17 of 18, 94%) of the breakpoints in RET were located within a 2.0-kb region spanning exon 11 to intron 11 and no breakpoint occurred within 4 bp of any other. This suggested that as in papillary thyroid carcinoma, DNA strand breaks formed at nonspecific sites within this region trigger RET fusion. Just over half of the RET fusions in LADC (10 of 18, 56%) were caused by simple reciprocal inversion, and two DNA-repair mechanisms, namely nonhomologous end joining and break-induced replication, were deduced to have contributed to the illegitimate joining of the DNA ends.
Oncogenic RET fusion in LADC occurs through multiple pathways and involves the illegitimate repair of DNA strand breaks through mechanisms different from those identified in papillary thyroid carcinoma, where RET fusion also functions as a driver mutation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nontransformed cells can force tumor cells to assume a normal morphology and phenotype by the process of contact normalization. Transformed cells must escape this process to become invasive and ...malignant. However, mechanisms underlying contact normalization have not been elucidated. Here, we have identified genes that are affected by contact normalization of Src-transformed cells. Tumor cells must migrate to become invasive and malignant. Src must phosphorylate the adaptor protein Cas (Crk-associated substrate) to promote tumor cell motility. We report here that Src utilizes Cas to induce podoplanin (Pdpn) expression to promote tumor cell migration. Pdpn is a membrane-bound extracellular glycoprotein that associates with endogenous ligands to promote tumor cell migration leading to cancer invasion and metastasis. In fact, Pdpn expression accounted for a major part of the increased migration seen in Src-transformed cells. Moreover, nontransformed cells suppressed Pdpn expression in adjacent Src-transformed cells. Of >39,000 genes, Pdpn was one of only 23 genes found to be induced by transforming Src activity and suppressed by contact normalization of Src-transformed cells. In addition, we found 16 genes suppressed by Src and induced by contact normalization. These genes encode growth factor receptors, adaptor proteins, and products that have not yet been annotated and may play important roles in tumor cell growth and migration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The clinical significance of cytomegalovirus (CMV) reactivation complicating ulcerative colitis (UC) patients has been uncertain. It has therefore remained undetermined whether or not CMV ...reactivation should be treated in UC patients under immunosuppression. The aim of the study was to clarify the natural history of CMV reactivation in UC patients.
Sixty-nine UC patients with moderate to severe activity were enrolled in the study. All of the patients were treated with prednisolone, and/or immunosuppressants such as cyclosporine A. We sequentially monitored CMV reactivation every 2 wk up until 8 wk using the CMV antigenemia (Ag) assay and plasma quantitative real-time polymerase chain reaction (PCR) assay for CMV.
Immunoglobulin (Ig) G for CMV was positive in 48 patients (69.6%) and negative in 21 patients (30.4%). CMV was reactivated in 25 patients out of the 48 seropositive patients (52.1%) during the study period. The CMV Ag and PCR values were low and none of the patients showed any evidence of CMV infection on biopsy specimens by hematoxylin and eosin staining. While gancylovir (GCV) was not used except in two patients, clinical outcomes including rates of remission and colectomy were not significantly different among the CMV reactivation-positive, -negative, and CMV IgG negative groups. Furthermore, CMV disappeared without GCV in most of the CMV reactivation-positive patients.
CMV is frequently reactivated in active UC patients; however, it disappears without antiviral agents. Therefore, antiviral therapies should not be necessary for most UC patients with only CMV reactivation as long as CMV Ag values are low.
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