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Genome sequencing has revealed frequent mutations in Ras homolog family member A (RHOA) among various cancers with unique aberrant profiles and pathogenic effects, especially in peripheral T-cell lymphoma (PTCL). The discrete positional distribution and types of RHOA amino acid substitutions vary according to the tumor type, thereby leading to different functional and biological properties, which provide new insight into the molecular pathogenesis and potential targeted therapies for various tumors. However, the similarities and discrepancies in characteristics of RHOA mutations among various histologic subtypes of PTCL have not been fully elucidated. Herein we highlight the inconsistencies and complexities of the type and location of RHOA mutations and demonstrate the contribution of RHOA variants to the pathogenesis of PTCL by combining epigenetic abnormalities and activating multiple downstream pathways. The promising potential of targeting RHOA as a therapeutic modality is also outlined. This review provides new insight in the field of personalized medicine to improve the clinical outcomes for patients.

Angioimmunoblastic T-cell lymphoma (AITL) is a malignant hematologic tumor arising from T follicular helper (Tfh) cells. High-throughput genomic sequencing studies have shown that AITL is characterized by a novel highly recurring somatic mutation in RHOA, encoding p.Gly17Val (RHOA G17V). However, the specific role of RHOA G17V in AITL remains unknown. Here, we demonstrated that expression of Rhoa G17V in CD4+ T cells increased cell proliferation and induces Tfh cell specification associated with Pon2 upregulation through an NF-κB-dependent mechanism. Further, loss of Pon2 attenuated oncogenic function induced by genetic lesions in Rhoa. In addition, an abnormality of RHOA G17V mutation and PON2 expression is also detected in patients with AITL. Our findings suggest that PON2 associated with RHOA G17V mutation might control the direction of the molecular agents-based AITL and provide a new therapeutic target in AITL.

PurposePrimary thymic extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a rare type of MALT lymphoma. We aim to investigate the clinicopathologic features, 18F-FDG PET/CT findings and outcomes for patients with primary thymic MALT lymphoma; to explore the correlation between metabolic parameters and immunohistochemical phenotypes.MethodsA retrospective single-center study enrolled 12 patients with primary thymic MALT lymphoma between 2010 and 2021. Nineteen 18F-FDG PET/CT scans were performed, and clinicopathologic and immunohistochemical characteristics, PET/CT imaging features, and outcomes were analyzed.ResultsThe male-to-female ratio was 1. The median age at diagnosis was 40 (range 31–68). The long diameter of the lesions ranged from 3.5 to 15.7. Histopathological examinations revealed that the normal thymic lobular architecture was effaced by a diffuse lymphoid infiltrate, but residual Hassall corpuscles could still be identified, mostly with CD20+, PAX5+, CD3-, CD23-, CD10-, BCL-6-, cyclin D1-, EBER- and low Ki-67. The gene rearrangement indicated that the IGH gene but not TCR gene was found in 7 patients. Six initial PET/CT scans showed a mean SUVmax of 6.8 (range, 3.1–12.4), a mean MTV = 40.0 (range, 6.7–81.4), and a mean TLG = 144.3 (range, 19.7–286.4). During the follow-up period, there was no death except for the patient with DLBCL who died 59 months after diagnosis of primary thymic MALT. No significant correlation between SUVmax and Ki-67 index was observed (r = 0.355, P > 0.05).ConclusionPrimary thymic MALT lymphoma should be considered in patients with multilocular cystic lesions with different degrees of 18F-FDG uptake in the anterior mediastinum. The results of this study showed no correlation between SUVmax and Ki-67 index.

Abstract Background In patients with squamous cell carcinoma of the cervix (SCCC), a squamous cell carcinoma (SqCC) in the lung represents either a second primary tumor or metastasis. This distinction between second primary tumors and lung metastases in patients with SCCC significantly influences patient prognosis and therapy. Here, we aimed to differentiate second primary tumors from lung metastases in patients with SCCC by exploring the HPV status in SqCCs involving the lung within a large cohort. Methods P16 expression was assessed using immunohistochemistry on tissue microarrays including a total of 415 primary lung SqCCs and 21 lung SqCCs with prior SCCC. Following this, we performed HPV DNA typing and the sensitive RNAscope in situ method to screen all the cases for HPV E6/E7 expression, which is a more reliable indicator of transcriptively active HPV in tumor cells. Results The p16 positive expression rate was 13.7% (57/415) in primary lung SqCCs, but HPV DNA was not detected in any of the 57 primary lung SqCC cases that positively expressed p16. In contrast, HPV DNA was detected in all cases (21/21) with prior SCCC. Consistently, all 21 lung SqCCs with prior SCCC (21/21) showed extensive HPV16 E6/E7 expression. In striking contrast, none of the primary lung SqCCs (0/415) had a detectable RNAscope signal. Conclusions HPV does not seem to play a role in the development of primary lung SqCCs. HPV detection may be helpful in distinguishing second primary tumors from lung metastases in patients with SCCC.

ObjectiveAngioimmunoblastic T cell lymphoma (AITL) is an aggressive form of non-Hodgkin lymphoma derived from mature T cells. However, the underlying pathogenesis of AITL remains unresolved. We aimed to explore the role of FOXO1-mediated signaling in the tumorigenesis and progression of AITL.MethodsFOXO1 expression was assessed using immunohistochemistry on a total of 46 AITL tissue samples. Retroviruses encoding FOXO1 shRNA were used to knockdown FOXO1 expression in CD4+ T cells. Flow cytometric assays analyzed the proliferation and survival of FOXO1 knockdown CD4+ T cells. Furthermore, we performed adoptive T-cell transfer experiments to identify whether inactivation of FOXO1 induced neoplastic follicular-helper T (Tfh) cell polarization and function.ResultsPatients with low FOXO1 protein levels were prone to have an advanced tumor stage (P = 0.049), higher ECOG ps (P = 0.024), the presence of bone marrow invasion (P = 0.000), and higher IPI (P = 0.035). Additionally, the survival rates of patients in the FOXO1 high-expression group were significantly better than those in the FOXO1 low-expression group (χ2 = 5.346, P = 0.021). We also observed that inactivation of FOXO1 increased CD4+ T cell proliferation and altered the survival and cell-cycle progression of CD4+ T cells. Finally, we confirmed that inactivation of FOXO1 induces Tfh cell programing and function.ConclusionsInactivation of FOXO1 in AITL plays a key role in the tumorigenesis and progression of AITL. We propose that FOXO1 expression could be a useful prognostic marker in AITL patients to predict poor survival, and to design appropriate therapeutic strategies.

Abstract Background Kindlin-2 is a member of the focal adhesion protein family that regulates invasion and metastasis in multiple malignancies; however, little is known about the role of Kindlin-2 in hepatocellular carcinoma (HCC) progression. Methods Immunohistochemistry was used to investigate Kindlin-2 expression in 177 pairs of human HCC and adjacent liver tissue samples. The role of Kindlin-2 in the in vitro invasion and migration of HCC cell lines was evaluated in MHCC97H, LM3 and SMMC7721 cells. Microarray expression analysis was applied to explore the molecular mechanism through which Kindlin-2 promoted HCC progression. Quantitative real-time PCR and Western blotting were performed to verify the microarray results. Results High Kindlin-2 expression was found to significantly correlate with aggressive HCC clinicopathological features including tumor encapsulation, microvascular invasion, extrahepatic metastasis and poor prognosis. In vitro, Kindlin-2 knockout or knockdown inhibited HCC cell adhesion, migration and invasion, while ectopic Kindlin-2 expression promoted these processes. Importantly, Kindlin-2 activated Wnt/β-catenin signaling and increased β-catenin expression, especially levels of non-phosphorylated β-catenin, as well as two Wnt/β-catenin signaling pathway targets, Axin2 and MMP7. Kindlin-2 also induced a change in the expression profile of HCC cells, suggesting the cells underwent epithelial-mesenchymal transition. For example, the expression of the epithelial marker E-cadherin was downregulated, while the mesenchymal markers Vimentin, N-cadherin and Snail were upregulated. Conclusion Kindlin-2 promotes HCC invasion, metastasis and epithelial-mesenchymal transition through Wnt/β-catenin signaling.

The application of current channelrhodopsin-based optogenetic tools is limited by the lack of strict ion selectivity and the inability to extend the spectra sensitivity into the near-infrared (NIR) tissue transmissible range. Here we present an NIR-stimulable optogenetic platform (termed 'Opto-CRAC') that selectively and remotely controls Ca2+ oscillations and Ca2+-responsive gene expression to regulate the function of non-excitable cells, including T lymphocytes, macrophages and dendritic cells. When coupled to upconversion nanoparticles, the optogenetic operation window is shifted from the visible range to NIR wavelengths to enable wireless photoactivation of Ca2+-dependent signaling and optogenetic modulation of immunoinflammatory responses. In a mouse model of melanoma by using ovalbumin as surrogate tumor antigen, Opto-CRAC has been shown to act as a genetically-encoded 'photoactivatable adjuvant' to improve antigen-specific immune responses to specifically destruct tumor cells. Our study represents a solid step forward towards the goal of achieving remote and wireless control of Ca2+-modulated activities with tailored function.

Angioimmunoblastic T cell lymphoma (AITL) represents a distinct, aggressive form of peripheral T cell lymphoma with a dismal prognosis. Recent exome sequencing in patients with AITL has revealed the frequent coexistence of somatic mutations in the Rho GTPase RhoA (RhoAG17V) and loss-of-function mutations in the 5-methylcytosine oxidase TET2. Here, we have demonstrated that TET2 loss and RhoAG17V expression in mature murine T cells cooperatively cause abnormal CD4+ T cell proliferation and differentiation by perturbing FoxO1 gene expression, phosphorylation, and subcellular localization, an abnormality that is also detected in human primary AITL tumor samples. Reexpression of FoxO1 attenuated aberrant immune responses induced in mouse models adoptively transferred with T cells and bearing genetic lesions in both TET2 and RhoA. Our findings suggest a mutational cooperativity between epigenetic factors and GTPases in adult CD4+ T cells that may account for immunoinflammatory responses associated with AITL patients. [ABSTRACT FROM AUTHOR]

Ras homolog enriched in brain (Rheb) is a key regulator of mammalian target of rapamycin complex 1 (mTORC1). The Rheb-mTORC1 axis is a pivotal pathway that mediates cell growth. It was previously reported that upon energy-stress stimulation, the phosphorylation of Rheb at serine 130 by p38-regulated/activated protein kinase (PRAK) results in the impaired nucleotide binding ability of Rheb and inhibits Rheb-mediated mTORC1 activation. However, the role of Rheb phosphorylation in cancer development remains to be elucidated. The aim of the present study was to determine the effect of Rheb phosphorylation on tumor growth in vitro and in vivo. In addition, tissue samples were obtained from 70 hepatocellular carcinoma (HCC) patients in order to determine any associations between Rheb phosphorylation and the clinicopathological characteristics of patients. In vitro and ex vivo kinase assays were performed to determine the phosphorylation of Rheb by PRAK. A xenograft assay was performed to assess tumorigenicity of MEF cell lines. In addition, western blot and immunohistochemical analyses were performed to detect Rheb protein expression and phosphorylation. The results of the present study revealed that Rheb phosphorylation may be induced through Ras overexpression. In addition, kinase-dead PRAK and dominant-negative PRAK mutation were demonstrated to abolish the Rheb phosphorylation induced by Ras overexpression. Xenograft assays in nude mice revealed that Rheb phosphorylation was involved in PRAK-mediated tumor suppression. Of note, the clinicopathological analysis of 70 HCC samples determined that Rheb phosphorylation was associated with poor proliferation and the progression of HCC. In conclusion, the results of the present study suggested that Rheb phosphorylation may have an important role as an intracellular barrier to cancer development. [ABSTRACT FROM AUTHOR]

Human GPKOW [G-patch (glycine-rich) domain and KOW (Kyrpides, Ouzounis and Woese) domain] protein contains a G-patch domain and two KOW domains, and is a homologue of Arabidopsis MOS2 and Saccharomyces Spp2 protein. GPKOW is found in the human spliceosome, but its role in pre-mRNA splicing remains to be elucidated. In this report, we showed that GPKOW interacted directly with the DHX16/hPRP2 and with RNA. Immuno-depletion of GPKOW from HeLa nuclear extracts resulted in an inactive spliceosome that still bound DHX16. Adding back recombinant GPKOW restored splicing to the depleted extract. In vivo, overexpression of GPKOW partially suppressed the splicing defect observed in dominant-negative DHX16 mutant expressing cells. Mutations at the G-patch domain greatly diminished the GPKOW-DHX16 interaction; however, the mutant was active in splicing and was able to suppress splicing defect. Mutations at the KOW1 domain slightly altered the GPKOW-RNA interaction, but the mutant was less functional in vitro and in vivo. Our results indicated that GPKOW can functionally impact DHX16 but that interaction between the proteins is not required for this activity. [ABSTRACT FROM AUTHOR]

Background and Aim To explore the expression and role of activating transcription factor 3 in human hepatocellular carcinoma. Methods Immunohistochemistry, Western blot assay and Real-time PCR were used to evaluate activating transcription factor 3 protein and gene level in HCC clinical samples. Results Activating transcription factor 3 expression is lowest in HCC, and the protein level is lower in patients with capsule invasion, while there is no association with other main clinical pathological features. Conclusions Low expression of ATF3 may function as a tumor suppressor during human hepatocellular oncogenesis and targeting ATF3 pathway might be beneficial for anti-HCC therapy. [ABSTRACT FROM AUTHOR]

Microsomal prostaglandin E2 synthase-1 (mPGES1), an inducible enzyme similar to cyclooxygenase-2, functions downstream of cyclooxygenase-2 in the synthesis of prostaglandin E2. It contributes to carcinogenesis in a variety of tumors. Here, mPGES1 expression was assessed using immunohistochemistry of tissue microarrays containing a total of 100 hepatocellular carcinoma (HCC) tissue samples, 100 peritumoral liver tissue samples, and 13 normal liver tissue samples. The expression of mPGES1 was significantly increased in the HCC tissue samples (P < .001), relative to normal liver tissue. Second, there was a significant positive correlation between mPGES1 expression and the Barcelona Clinic Liver Cancer stage (P < .001) inHCC tissue samples. This correlation was also observed with encapsulation (P = .004) and portal vein thrombosis (P < .001). In addition, the lentiviral vector (Lv-mPGES1-shRNA), which down-regulates mPGES1, inhibited tumor growth in an HCC animal model. Taken together, mPGES1 expression was associated with multiple malignant characteristics and enhanced tumorigenesis in HCC and may serve as an important clinical and pharmacologic biomarker. [ABSTRACT FROM AUTHOR]

Signaling of transforming growth factor β (TGF-β) is redirected in cancer to promote malignancy, but how TGF-β function is altered in a transformed cell is not fully understood. We investigated TGF-β signaling by profiling proteins that differentially bound to type I TGF-β receptor (TβRI) in nontransformed, HER2-transformed, and HER2-negative breast cancer cells using immunoprecipitation followed by protein identification. Interestingly, several nuclear proteins implicated in posttranscriptional RNA processing were uniquely identified in the TβRI coprecipitates from HER2-transformed cells. Ligand-inducible nuclear translocation of TβRI was observed only in transformed cells, and the translocation required importin β1, nucleolin, and Smad2/3. This trafficking was dependent on the high Ran GTPase activity resulting from oncogenic transformation. In the nucleus, TβRI associated with purine-rich RNA sequences in a synergistic manner with the RNA-binding factor hnRNP A1. We further found that nuclear translocation of TβRI specifically induced epidermal growth factor receptor (EGFR) transcript isoform c, which encodes a soluble EGFR protein, through alternative splicing or 3'-end processing. Our study confirms a cancer-specific nuclear translocation of TβRI and demonstrates its potential function in regulating nuclear RNA processing, as well as a novel gain-of-function mechanism of TGF-β signaling in cancer. [ABSTRACT FROM AUTHOR]

KiSS-1 has been identified as a putative metastasis-suppressor gene in human melanomas and breast cancer cell lines. Although loss of KiSS-1 expression has been associated with progression and poor prognosis of various cancers, the exact role of KiSS-1 expression in HCC is not well-defined. Our study investigated KiSS-1 expression levels in HCC and its role in invasion and metastasis of human HCC. The expression levels of KiSS-1 and MMP-9 protein were determined by tissue microarray (TMA) serial sections, immunohistochemistry and semi-quantitative image analysis. All clinical and histological data obtained were subjected to statistical analysis. The expression of KiSS-1 protein in HCC and intrahepatic metastasis lesions was significantly lower (P < 0.01) when compared with non-tumor liver tissue and normal liver tissue. Multivariate analysis revealed a significant inverse correlation between KiSS-1 expression and o1 TNM stage, (F = 7.113, P < 0.01) and o2 intrahepatic metastasis (t = 2.898, P < 0.01). Loss of KiSS-1 in intrahepatic metastasis versus primary carcinomas was statistically significant (P<0.01). We also found a negative correlation between KiSS-1 and MMP-9 expression in HCC (r = -0.506, P < 0.01). We conclude that loss of KiSS-1 during HCC metastasis, along with a concomitant upregulation of MMP-9 suggests a possible mechanism for cell motility and invasion during HCC metastasis, with KiSS-1 emerging as a possible therapeutic target during HCC metastasis., ((c) 2009 Wiley-Liss, Inc.)