LncRNA DYNLRB2-AS1 promotes gemcitabine resistance of nasopharyngeal carcinoma by inhibiting the ubiquitination degradation of DHX9 protein.

Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15 % of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.

Induction-concurrent chemoradiotherapy with or without sintilimab in patients with locoregionally advanced nasopharyngeal carcinoma in China (CONTINUUM): a multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial.

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Angioimmunoblastic T-cell lymphoma involving the nasopharynx: An easily misdiagnosed disease with atypical histopathological features.

OBJECTIVES: To explore the clinicopathologic features, treatment, and survival outcomes of angioimmunoblastic T-cell lymphoma (AITL) involving the nasopharynx. METHODS: We retrospectively analyzed 73 cases of AITL. Among them, 64 cases with complete pre-treatment 18F-FDG positron emission tomography/computed tomography (PET/CT) images were integrated into the analysis of clinical characteristics and PET/CT findings of AITL involving the nasopharynx; 14 cases with both biopsies from lymph node and nasopharynx were included in the comparison of pathological characteristics of AITL in the two areas. Forty-six of the 73 patients who received first-line systemic treatment at our institute were included in the treatment efficacy and survival analyses. RESULTS: Nasopharyngeal involvement was seen in 44/64 (68.8%) patients. Histologically, lymph node and nasopharyngeal biopsies in 14 patients both showed small to medium-sized tumor cells, complex inflammatory infiltration, and Reed-Sternberg-like cells or B immunoblasts. However, tumor cells with clear cytoplasm, significant high endothelial venule (HEV) hyperplasia, and perivascular infiltration were observed in 5/14, 3/14, and 2/14 nasopharyngeal biopsies, respectively, but in all fourteen lymph node biopsies (P < 0.05). Immunophenotypic profiles and gene rearrangements were highly concordant. Treatment efficacy and survival were similar between patients with nasopharyngeal involvement and those without (P > 0.05), indicating nasopharyngeal involvement is not a prognostic factor for AITL patients. CONCLUSIONS: Nasopharyngeal involvement is common in AITL but can be easily misdiagnosed because of its atypical pathologic pattern, especially when a lymph node biopsy is unavailable. However, the patient's clinical presentation, PET/CT manifestations, the typical immunophenotype, and gene rearrangements help the diagnosis.

Extranodal NK/T-Cell Lymphoma Predominantly Composed of Anaplastic Cells: A Frequently Misdiagnosed and Highly Aggressive Variant.

Extranodal NK/T-cell lymphoma (ENKTL) is a non-Hodgkin lymphoma associated with the Epstein-Barr virus that primarily affects individuals in East Asia and indigenous populations in Central and South America. Morphologically, ENKTL typically consists of medium-sized cells or a combination of small and large cells. This report presents 10 cases characterized by predominantly anaplastic cells with diffuse expression of CD30, resembling anaplastic lymphoma kinase-negative anaplastic large cell lymphoma (ALK-negative ALCL) and demonstrating highly aggressive behavior. The cohort included 9 males and 1 female, ranging in age from 29 to 65 years (median age: 47 y). Eight patients presented with nasal disease, while 2 had non-nasal disease. Five patients had stage I/II disease, and the remaining 5 had stage III/IV disease. Morphologically, necrosis was observed in 9 cases, angiocentric-angiodestructive growth in 3 cases, and pseudoepitheliomatous hyperplasia in 2 cases. Anaplastic cells predominated in all cases, with some displaying eccentric, horseshoe-shaped, or kidney-shaped nuclei (referred to as "Hallmark" cells). The morphology profile was monomorphic in 3 cases and polymorphic in 7 cases. Immunohistochemically, all cases tested positive for cytotoxic granule markers (TIA1 and granzymeB) and Epstein-Barr virus-encoded RNA. Cytoplasmic expression of CD3ε and CD56 was observed in 9 of 10 cases. Interestingly, most cases (7 of 8) exhibited variable expression of MuM1, ranging from 10% to 90%. All cases showed diffuse positivity for CD30 but were negative for ALK, resulting in 3 cases being initially misdiagnosed as ALK-negative ALCL. Compared with nonanaplastic cases, anaplastic cells predominant ENKTL had a significantly higher frequency of "B" symptoms, bone marrow involvement, hemophagocytic lymphohistiocytosis, and higher Ki67 proliferative index. These findings provide valuable information for pathologists, expanding their understanding of the cytologic spectrum of ENKTL. This rare variant of ENKTL, characterized by the predominance of anaplastic cells and diffuse CD30 expression, exhibits high aggressiveness and should be differentiated from ALK-negative ALCL. Awareness of this uncommon variant is crucial in preventing misdiagnosis and ensuring the timely initiation of therapy.

PD-L1 expression in recurrent or metastatic head and neck squamous cell carcinoma in China (EXCEED study): a multicentre retrospective study.

AIMS: Programmed death-ligand 1 (PD-L1) is known to be highly expressed in various malignancies, including head and neck squamous cell carcinoma (HNSCC). We aimed to determine the prevalence of PD-L1 expression in recurrent or metastatic HNSCC (R/M HNSCC) among Chinese patients. METHODS: This multicentre, retrospective analysis of data from six centres in China included patients with R/M HNSCC treated from 9 August 2021 to 28 February 2022. PD-L1 expression in tumour tissue was assessed and represented using a combined positive score (CPS). The χ2 and Cochran-Mantel-Haenszel χ2 tests were used to compare the prevalence of different PD-L1 expression statuses according to related co-variables. RESULTS: For all 402 examined patients with R/M HNSCC, 168 cases (41.8%) had PD-L1 expression with a CPS ≥20, and 337 cases (83.8%) had PD-L1 expression with a CPS ≥1. Between the PD-L1 CPS ≥20 group and PD-L1 CPS <20 group, statistically significant differences were observed for variables of sex (p<0.001), smoking habit (p=0.0138 for non-smokers vs current smokers) and primary tumour site (p<0.001 for hypopharynx vs oral cavity and p=0.0304 for larynx vs oral cavity, respectively). CONCLUSION: PD-L1 with CPS ≥20 was expressed in about 41.8% of cases with R/M HNSCC among Chinese patients, and PD-L1 expression was significantly associated with sex, smoking history and primary tumour site. Our findings regarding the variables related to PD-L1 expression level provide insight for clinical practice and a solid basis for future research on immunotherapy in HNSCC. TRIAL REGISTRATION NUMBER: ISRCTN10570964.

Detection of Human Papillomavirus DNA, E6/E7 Messenger RNA, and p16INK4a in Lung Cancer: A Systematic Review and Meta-analysis.

BACKGROUND: The etiologic link between human papillomavirus (HPV) and lung cancer is still controversial. METHODS: PubMed and Cochrane databases were searched from inception to December 2020 to identify studies on the infection of HPV in lung cancer. We calculated the attributable proportion of HPV in lung cancer by pooling the infection of cases positive for both HPV DNA and biomarkers of carcinogenesis that may be induced by HPV (E6/E7 messenger RNA or p16INK4a). RESULTS: A total of 117 studies, comprising data of 12 616 lung cancer cases from 22 countries across 5 continents, were included. The overall HPV DNA positivity in primary lung cancer cases worldwide was 16.4% (95% confidence interval, 12.7%-20.5%). HPV DNA positivity of lung cancer varied significantly by pathological type and geographic region. Notably, the expression rate of p16INK4a is significantly higher than the positivity of HPV DNA and of HPV E6/E7 mRNA (P < .05). The estimate of HPV attributable proportion defined by expression of E6/E7 mRNA was 0 and of p16INK4a was 7.3%. CONCLUSIONS: The data in this systematic review is robust enough to contradict the possible participation of HPV in lung cancer carcinogenesis. Prophylactic vaccines targeting HPV cannot have the potential to prevent lung cancer.

Targeting TET2 as a Therapeutic Approach for Angioimmunoblastic T Cell Lymphoma.

Angioimmunoblastic T-cell lymphoma (AITL), a type of malignant lymphoma with unique genomic aberrations, significant clinicopathological features, and poor prognosis, is characterized by immune system dysregulation. Recent sequencing studies have identified recurrent mutations and interactions in tet methylcytosine dioxygenase 2 (TET2), ras homology family member A (RHOA), DNA methyltransferase 3 alpha (DNMT3A), and mitochondrial isocitrate dehydrogenase II (IDH2). Notably, since B-cell lymphomas are frequently observed along with AITL, this review first summarizes its controversial mechanisms based on traditional and recent views. Epigenetic regulation represented by TET2 plays an increasingly important role in understanding the multi-step and multi-lineage tumorigenesis of AITL, providing new research directions and treatment strategies for patients with AITL. Here, we review the latest advances in our understanding of AITL and highlight relevant issues that have yet to be addressed in clinical practice.

RHOA G17V induces T follicular helper cell specification and involves angioimmunoblastic T-cell lymphoma via upregulating the expression of PON2 through an NF-κB-dependent mechanism.

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.

Thymic Extranodal Marginal-Zone Lymphoma of Mucosa-Associated Lymphoid Tissue: Pathological Features, 18F-FDG PET/CT Findings and Prognosis in 12 Cases.

Purpose: Primary 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. Methods: A 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. Results: The 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). Conclusion: Primary 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.

Application of 18F Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography in Monitoring Gastric Metastasis and Cancer Thrombi from Renal Cell Carcinoma.

BACKGROUND: Renal cell carcinoma (RCC) with gastric metastasis is rare, particularly accompanied by multiple cancer thrombi. METHODS: We reported a 66-year-old man with a history of a right radical nephrectomy because of RCC. The patient underwent 18F prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) scanning after 6 months of targeted therapy because of gastric metastasis and cancer thrombi. We conducted a systematic review of the literature and identified 73 cases of RCC with gastric metastasis. We analyzed the clinicopathological characteristics, therapies, and outcomes of patients. RESULTS: 18F-PSMA PET/CT showed a large mass in the gastric fundus and cancer thrombi in the right atrium, inferior vena cava, and splenic vein with intense tracer uptake. Other metastases with increased tracer uptake included multiple bones and abdominal lymph nodes. The majority of gastric metastasis of RCC were men (53/73, 72.6%), with a median age at presentation of 67 (from 48 to 87) years. Gastric metastasis of RCC was mainly metachronous, and presented with small polyps or mass appearance and often accompanied by multiple-site metastases and gastrointestinal symptoms. An overall median interval between nephrectomy and diagnosis of gastric metastasis was 6 (from 0.1 to 23) years, and an overall median survival time was 14 (from 0.25 to 72) months. The median interval time of solitary gastric metastasis was longer than gastric metastasis with multiple-site metastases (7 vs.5 years; P=0.034). Patients with gastric and multiple-site metastases had higher mortality than patients with solitary metastasis (17 vs.1; P=0.028). The patients with synchronous gastric metastasis had a shorter survival time than metachronous gastric metastasis (6 vs.17 months; P=0.018). CONCLUSIONS: Postoperative follow-up of multiple imaging modalities to monitor recurrence and metastasis is necessary and important. PSMA PET/CT can improve the detection sensitivity of RCC, especially in metastatic clear cell renal cell carcinoma (ccRCC), and could provide a basis for disease staging, restaging, and therapeutic efficacy evaluation.

Detection of human papillomavirus distinguishes second primary tumors from lung metastases in patients with squamous cell carcinoma of the cervix.

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.

Signet ring cell component in pretreatment biopsy predicts pathological response to preoperative chemoradiotherapy in rectal cancer.

PURPOSE: Neoadjuvant therapy is routinely used in the management of locally advanced rectal cancer. This study aimed to evaluate the predictive value of pathological parameters in tumor response after treatment. METHODS: We reviewed the hematoxylin-eosin slides from pretreatment biopsies of 150 rectal cancer patients who received preoperative chemoradiotherapy (PCRT) at Sun Yat-sen University Cancer Center between May 2013 and June 2016. Pathological and clinical parameters were both studied. The tumor response after chemoradiotherapy was evaluated using the tumor regression grade (TRG). Logistic regression was used to evaluate the relevance between these parameters and tumor response. RESULTS: Complete tumor response (TRG0 and pCR) to PCRT was identified in 40 (26.7%) patients. The pCR rate was 93.33% (14 of 15) in cases with signet ring cell component versus 19.26% (26 of 135) in those without signet ring cell component (p < 0.001). Four cases with signet ring cell component were evaluated as clinical complete response (cCR), all of whom also achieved pCR; in contrast, only 9 of 15 (60%) cCR cases without signet ring cell achieved pCR. CONCLUSION: Our data suggest that the signet ring cell component in pretreatment biopsies may be a potential predictor of tumor response to PCRT in rectal cancer. This suggests patients with clinical complete response are more suitable for a wait-and-watch approach.

Antibiotic treatment ameliorates Ten-eleven translocation 2 (TET2) loss-of-function associated hematological malignancies.

TET2 is among the most frequently mutated genes in hematological malignancies, as well as in healthy individuals with clonal hematopoiesis. Inflammatory stress is known to promote the expansion of Tet2-deficient hematopoietic stem cells, as well as the initiation of pre-leukemic conditions. Infection is one of the most frequent complications in hematological malignancies and antibiotics are commonly used to suppress infection-induced inflammation, but their application in TET2 mutation-associated cancers remained underexplored. In this study, we discovered that Tet2 depletion led to aberrant expansion of myeloid cells, which was correlated with elevated serum levels of pro-inflammatory cytokines at the pre-malignant stage. Antibiotics treatment suppressed the growth of Tet2-deficient myeloid and lymphoid tumor cells in vivo. Transcriptomic profiling further revealed significant changes in the expression of genes involved in the TNF-α signaling and other immunomodulatory pathways in antibiotics-treated tumor cells. Pharmacological inhibition of TNF-α signaling partially attenuated Tet2-deficient tumor cell growth in vivo. Therefore, our findings establish the feasibility of targeting pro-inflammatory pathways to curtail TET2 inactivation-associated hematological malignancies.

Inactivation of FOXO1 induces T follicular cell polarization and involves angioimmunoblastic T cell lymphoma.

Objective: Angioimmunoblastic 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. Methods: FOXO1 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. Results: Patients 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. Conclusions: Inactivation 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.

Overexpression of activating transcription factor 3 exerts suppressive effects in HepG2 cells.

The present study observed and compared the biological behaviour of HepG2 cells prior and subsequent to the overexpression of activating transcription factor 3 (ATF3). Experiments investigating the cytological function by which ATF3 affects liver cancer cells were also performed. MTT, Transwell and flow cytometry assays were used to observe and detect the biological behaviour of HepG2 cells with and without lentivirus (LV)­ATF3­enhanced green fluorescent protein (EGFP) infection. The effects of ATF3 overexpression on cell proliferation, migration, apoptosis and cell cycle progression were evaluated. The LV­ATF3­EGFP overexpression vector was successfully constructed, and the HepG2 cells were successfully infected with the vector. Following ATF3 overexpression, cell proliferation was decreased, the rate of cell apoptosis was accelerated and cell cycle progression was slowed (P<0.05). There were no marked changes in cell migration (P>0.05), although there was a trend towards a gradual decrease. In conclusion, ATF3 exerted suppressive effects in HepG2 cells, potentially by inhibiting cancer cell growth, accelerating cell apoptosis, and blocking cell cycle progression. Intervention targeting ATF3 expression may represent a novel approach for the prevention and treatment of human liver cancer.

MYLK promotes hepatocellular carcinoma progression through regulating cytoskeleton to enhance epithelial-mesenchymal transition.

Myosin light chain kinase (MYLK) is found to catalyze the phosphorylation of myosin light chains (MLC) and regulate invasion and metastasis in some malignancies. However, there is little knowledge on the role of MYLK in hepatocellular carcinoma (HCC), and no studies have been conducted to investigate the mechanisms underlying MYLK-mediated promotion of HCC invasion and metastasis until now. In this study, we investigated the expression of MYLK in 50 pairs of human HCC and adjacent liver specimens. High MYLK expression was significantly correlated with aggressive clinicopathological features including tumor encapsulation, microvascular invasion and metastasis. In vitro assays showed that shRNA-induced MYLK knockdown significantly inhibited the wound-healing ability of HCC cells and the ability to migrate and invade through Matrigel. We next uncovered that MYLK knockdown resulted in a reduction in the number of F-actin stress fibers, disorganization of F-actin architectures and morphological alterations of HCC cells. Phosphorylated MLC, rather than total MLC, was found to be markedly reduced in response to downregulation of MYLK expression, and MYLK-regulated actin cytoskeleton through phosphorylating MLC in HCC cells. In addition, Western blotting assay revealed downregulation of the epithelial marker E-cadherin and upregulation of mesenchymal markers Vimentin, N-cadherin and Snail. Taken together, our findings indicate that MYLK promotes HCC progression by altering cytoskeleton to enhance epithelial-mesenchymal transition (EMT).

Correlation of lysosome-associated protein transmembrane-4ß gene overexpression with the malignant phenotypes of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common and rapidly fatal malignancies, for which hepatitis B virus (HBV) chronic infection constitutes a major risk factor. The lysosome-associated protein transmembrane-4 ß gene (LAPTM4B) is a recently identified gene that was found to be overexpressed in several types of cancer. However, the role of LAPTM4B in HCC tumorigenesis and progression has not been clearly determined. The present study demonstrated that the mRNA as well as the protein levels of LAPTM4B were significantly upregulated in HCC specimens. Patients with higher levels of LAPTM4B mRNA in their HCC tissues tended to be of a younger age, HBsAg+, with an advanced Barcelona Clinic Liver Cancer stage. Moreover, LAPTM4B mRNA expression was positively associated with serum α -fetoprotein levels. We also observed that LAPTM4B was able to promote HCC cell proliferation, migration and invasion in vitro. In conclusion, our results indicated that LAPTM4B plays an important role in the promotion of hepatocarcinogenesis and cancer progression and may serve as a biomarker for the diagnosis and monitoring of HCC.

Kindlin-2 promotes hepatocellular carcinoma invasion and metastasis by increasing Wnt/ß-catenin signaling.

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/ß-catenin signaling and increased ß-catenin expression, especially levels of non-phosphorylated ß-catenin, as well as two Wnt/ß-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/ß-catenin signaling.

Mutations in 5-methylcytosine oxidase TET2 and RhoA cooperatively disrupt T cell homeostasis.

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.