Comprehensive pan-cancer analysis reveals that C5orf34 regulates the proliferation and mortality of lung cancer.

The gene C5orf34 exhibits evolutionary conservation among mammals, and emerging evidence suggests its potential involvement in tumor development; however, comprehensive investigations of this gene are lacking. This study aims to elucidate the functional attributes and underlying mechanisms of C5orf34 in cancer. To evaluate its clinical predictive value, we conducted an analysis of the pan-cancerous expression, clinical data, mutation, and methylation data of C5orf34. Additionally, we investigated the correlation between C5orf34 and tumor mutant load (TMB), immune cell infiltration, and microsatellite instability (MSI) through relevant analyses. Furthermore, immunohistochemical (IHC) staining was employed to validate clinical samples, while knockdown and overexpression experiments and transcriptome RNA sequencing were utilized to examine the impact of C5orf34 on LUAD cells. According to our study, C5orf34 exhibits high expression levels in the majority of malignant tumors. The upregulation of C5orf34 is governed by DNA copy number alterations and methylation patterns, and it is closely associated with patients' survival prognosis and immune characteristics, thereby holding significant clinical implications. Furthermore, IHC staining analysis, cellular experiments, and transcriptome RNA sequencing have provided evidence supporting the role of C5orf34 in modulating the cell cycle to promote LUAD proliferation, migration, and invasion. This highlights its potential as a promising therapeutic target. The findings of this investigation suggest that C5orf34 may serve as a valuable biomarker for various tumor types and represent a potential target for immunotherapy, particularly in relation to the proliferation, migration, and apoptosis of LUAD cells.

Connexin32 activates necroptosis through Src-mediated inhibition of caspase 8 in hepatocellular carcinoma.

Necroptosis is an alternative form of programmed cell death that generally occurs under apoptosis-deficient conditions. Our previous work showed that connexin32 (Cx32) promotes the malignant progress of hepatocellular carcinoma (HCC) by enhancing the ability of resisting apoptosis in vivo and in vitro. Whether triggering necroptosis is a promising strategy to eliminate the apoptosis-resistant HCC cells with high Cx32 expression remains unknown. In this study, we found that Cx32 expression was positively correlated with the expression of necroptosis protein biomarkers in human HCC specimens, cell lines, and a xenograft model. Treatment with shikonin, a well-used necroptosis inducer, markedly caused necroptosis in HCC cells. Interestingly, overexpressed Cx32 exacerbated shikonin-induced necroptosis, but downregulation of Cx32 alleviated necroptosis in vitro and in vivo. Mechanistically, Cx32 was found to bind to Src and promote Src-mediated caspase 8 phosphorylation and inactivation, which ultimately reduced the activated caspase 8-mediated proteolysis of receptor-interacting serine-threonine protein kinase 1/3, the key molecule for necroptosis activation. In conclusion, we showed that Cx32 contributed to the activation of necroptosis in HCC cells through binding to Src and then mediating the inactivation of caspase 8. The present study suggested that necroptosis inducers could be more favorable than apoptosis inducers to eliminate HCC cells with high expression of Cx32.

MiR-449b-5p targets lncRNA PSMG3-AS1 to suppress cancer cell proliferation in lung adenocarcinoma.

BACKGROUND: PSMG3-AS1 has been characterized as an oncogenic lncRNA in breast cancer, while its role in other cancers is unknown. This study investigated the role of PSMG3-AS1 in lung adenocarcinoma (LUAD). METHODS: This study included 64 LUAD patients (42 males and 22 females) who were enrolled between May 2012 and May 2014. RT-qPCR was used to evaluate the expression levels of lncRNA. Cell proliferation analysis was performed using CCK-8 kit. RESULTS: We found that upregulation of PSMG3-AS1 in LUAD predicted the poor survival of patients. MiR-449b-5p is downregulated in LUAD and the expression levels of LUAD were inversely correlated with the expression levels of PSMG3-AS1. MiR-449b-5p was predicted to target PSMG3-AS1, and overexpression of miR-449b-5p resulted in the downregulation of PSMG3-AS1 in LUAD cells. Cell proliferation analysis showed that overexpression of PSMG3-AS1 resulted in increased rate of cell proliferation. Overexpression of miR-449b-5p reduced the enhancing effects of PSMG3-AS1 on cell proliferation. CONCLUSIONS: Therefore, miR-449b-5p may target PSMG3-AS1 in LUAD to suppress cancer cell proliferation.

Pattern of cell-to-cell transfer of microRNA by gap junction and its effect on the proliferation of glioma cells.

MicroRNA is expected to be a novel therapeutic tool for tumors. Gap junctions facilitate the transfer of microRNA, which exerts biological effects on tumor cells. However, the length of microRNA that can pass through certain gap junctions composed of specific connexin remains unknown. To address this question, the present study investigated the permeability of gap junctions composed of various connexins, including connexin 43, connexin 32 or connexin 37, to microRNAs consisting of 18-27 nucleotides in glioma cells and cervical cancer cells. Results indicated that all of the microRNAs were able to be transferred from donor glioma cells to neighboring cells through the connexin 43 composed gap junction, but not the gap junctions composed of connexin 32 or connexin 37, in cervical cancer cells. Downregulation of the function of gap junctions comprising connexin 43 by pharmacological inhibition and shRNA significantly decreased the transfer of these microRNAs. In contrast, gap junction enhancers and overexpression of connexin 43 effectively increased these transfers. In glioma cells, cell proliferation was inhibited by microRNA-34a. Additionally, these effects of microRNA-34a were significantly enhanced by overexpression of connexin 43 in U251 cells, indicating that gap junctions play an important role in the antitumor effect of microRNA by transfer of microRNA to neighboring cells. Our data are the first to clarify the pattern of microRNA transmission through gap junctions and provide novel insights to show that antitumor microRNAs should be combined with connexin 43 or a connexin 43 enhancer, not connexin 32 or connexin 37, in order to improve the therapeutic effect.

[Epstein-Barr virus infection and expression of latent membrane protein 2A in Hodgkin's lymphoma of Uygur patients].

OBJECTIVE: To investigate Epstein-Barr virus(EBV) infection in Hodgkin's lymphoma (HL) of Uygur patients and related clinicopathological characteristics. METHODS: EBV-encoded small RNA (EBER) was detected in 40 cases of HL and 20 cases of lymphoid reactive hyperplasia by in-situ hybridization. Expression of LMP2A in HL was investigated by immunohistochemistry. RESULTS: EBV was detected in 26/40 (65.0%) of HL and 5/20 of lymphoid reactive hyperplasia (P < 0.05). The expression level of EBER showed significant difference among various histological subtypes of HL (P < 0.05) and between patients with and without B symptom (P = 0.02). However, no difference was found in relation to gender, clinical stage and tumor burden. The expression of LMP2A in the mixed cellularity and nodular sclerosis classical HL associated with EBV infection was 57.7% (15/26). Expression of LMP2A was not detected in lymphoid reactive hyperplasia cases. CONCLUSION: Uyghur patients with Hodgkin's lymphoma have a high infection rate of EBV and distinct clinicopathologic characteristics.

Analysis of Clinicopathological Features of Cervical Mucinous Adenocarcinoma with a Solitary Ovarian Metastatic Mass as the First Manifestation.

PURPOSE: To avoid misdiagnosis, clinicopathological features were analyzed in cases of cervical mucinous adenocarcinoma with solitary ovarian metastatic masses. PATIENTS AND METHODS: Three cases misdiagnosed as primary ovarian adenocarcinoma before surgery were filtered from the database of the Cancer Hospital/Chinese Academy of Medical Sciences from January 1998 to December 2016. The clinical data were thoroughly collected and compared, and both frozen and paraffin-embedded pathological sections were reviewed by two expert pathologists. RESULTS: None of the patients experienced cervical contact bleeding, and no typical cervical neoplasms were found. The cervical canals were slightly thickened in two patients, as detected by either palpation or imaging. The high-risk human papillomavirus (HPV) test results were all negative, and the thin-prep cytologic test (TCT) screened only one case of atypical glandular epithelial cells. All cases were indicative of higher serum CA19-9 levels (79.49-6124 U/mL). The ovarian masses showed no regular laterality, while they were all cystic or solid-cystic. Their pathological sections indicated a benign appearance of the capsule tissue with well-differentiated mucinous glands infiltrating the ovarian cortex with focal necrosis. CONCLUSION: Attention should be paid to cervical examinations before and during surgery for cervical mucinous adenocarcinoma with a metastatic ovarian mass as the first manifestation. Such patients may gain a better prognosis after active treatment.

Cx32 exerts anti-apoptotic and pro-tumor effects via the epidermal growth factor receptor pathway in hepatocellular carcinoma.

BACKGROUND: Abnormal expression or distribution of connexin 32 (Cx32) is associated with hepatocarcinogenesis, but the role of Cx32 and the underlying mechanisms are still unclear. METHODS: The expression level of Cx32 in 96 hepatocellular carcinoma (HCC) specimens was determined using western blotting and immunohistochemistry. The correlation between Cx32 expression and clinicopathological parameters was analyzed. The cell apoptosis rate was examined using flow cytometry and western blotting. The role of Cx32 in the Src kinase and epidermal growth factor receptor (EGFR) signaling pathways was measured by quantitative real-time PCR, western blotting and coimmunoprecipitation (CO-IP). The effect of Cx32 overexpression on the streptonigrin (SN)-induced tumor growth suppression and apoptosis was assessed in nude mice. RESULTS: Our study showed that overexpressed Cx32 accumulated in the cytoplasm and that Cx32-containing gap junctions (GJs) were nearly absent in HCC specimens. Upregulated Cx32 expression was highly correlated with advanced tumor-node-metastasis (TNM) stage and poor tumor differentiation and was an independent predictive marker for poor prognosis in HCC. Overexpression of Cx32 significantly inhibited SN-induced apoptosis by activating the EGFR signaling pathway in vitro and in vivo. Moreover, the expression levels of Cx32 and EGFR were positively correlated in HCC specimens. The CO-IP experiments demonstrated that Cx32 could bind to Src kinase, and the western blotting results revealed that Cx32 increased the levels of EGFR and p-EGFR by upregulating Src expression. CONCLUSION: The present study demonstrated that overexpressed and internalized Cx32 was associated with advanced TNM stage and poor tumor differentiation and predicted poor prognosis in HCC. Cx32 facilitated HCC progression by blocking chemotherapy-induced apoptosis in vitro and in vivo via interacting with Src and thus promoting the phosphorylation of EGFR, subsequently activating the EGFR signaling pathway. Cx32 may be a potential biomarker and a new therapeutic target for HCC.

Non-junctional Cx32 mediates anti-apoptotic and pro-tumor effects via epidermal growth factor receptor in human cervical cancer cells.

The role of connexin proteins (Cx), which form gap junctions (GJ), in progression and chemotherapeutic sensitivity of cervical cancer (CaCx), is unclear. Using cervix specimens (313 CaCx, 78 controls) and CaCx cell lines, we explored relationships among Cx expression, prognostic variables and mechanisms that may link them. In CaCx specimens, Cx32 was upregulated and cytoplasmically localized, and three other Cx downregulated, relative to controls. Cx32 expression correlated with advanced FIGO staging, differentiation and increased tumor size. In CaCx cell lines, Cx32 expression suppressed streptonigrin/cisplatin-induced apoptosis in the absence of functional GJ. In CaCx specimens and cell lines, expression of Cx32 upregulated epidermal growth factor receptor (EGFR) expression. Inhibition of EGFR signaling abrogated the anti-apoptotic effect of Cx32 expression. In conclusion, upregulated Cx32 in CaCx cells produces anti-apoptotic, pro-tumorigenic effects in vivo and vitro. Abnormal Cx32 expression/localization in CaCx appears to be both a mechanism and biomarker of chemotherapeutic resistance.

GATA3 is a sensitive marker for primary genital extramammary paget disease: an immunohistochemical study of 72 cases with comparison to gross cystic disease fluid protein 15.

BACKGROUND: GATA-binding protein 3 (GATA3) has been identified as a sensitive marker for breast carcinoma but its sensitivity in primary genital extramammary Paget diseases (EMPDs) has not been well studied. METHODS: Here we investigated immunohistochemical expression of GATA3 in 72 primary genital EMPDs (35 from female, 37 from male; 45 with intraepithelial disease only, 26 with both intraepithelial disease and invasive adenocarcinoma including 14 also metastasis, 1 with metastatic adenocarcinoma only for study). We also compared GATA3 to gross cystic disease fluid protein 15 (GCDFP15) for their sensitivity. RESULTS: Positive GATA3 staining was seen in all 71 (100%) intraepithelial diseases, 25/26 (96%; female 10/10, male 15/16) invasive adenocarcinomas and 14/15 (93%; female 3/3, male 11/12) metastatic adenocarcinomas, respectively. Positive GCDFP15 staining was seen in 46/71 (65%; female 28/34 or 82%, male 18/37 or 49%) intraepithelial diseases, 20/26 (77%; female 9/10, male 11/16) invasive adenocarcinomas, and 12/15 (80%; female 2/3, male 10/12) metastatic adenocarcinomas, respectively (GATA3 versus GCDFP15: p < 0.01 for both intraepithelial disease and invasive adenocarcinoma, p = 0.28 for metastatic adenocarcinoma). In positive-stained cases, GATA3 stained more tumor cells than GCDFP15 (79% versus 25% for intraepithelial disease, 71% vs 34% for invasive adenocarcinoma, 73% vs 50% for metastatic adenocarcinoma, p < 0.01 for all 3 components). CONCLUSIONS: Our findings indicate that GATA3 is a very sensitive marker for primary genital EMPDs and is more sensitive than GCDFP15.

Clinical significance of quantitative analysis of plasma epstein- barr virus DNA in patients of Xinjiang Uygur nationality with Hodgkin's Lymphoma.

OBJECTIVE: To investigate the relationship between plasma EBV-DNA concentration and clinicopathologic features of Hodgkin's lymphoma cases. METHODS: At first, the positive rate of plasma EBV-DNA was determined with a nested-PCR method using 45 specimens from Uygur HL patients, as well as 110 healthy people sampled as normal controls. Secondly, using fluorescent quantitative nested-PCR, EBV viral load was assessed in the EBV-DNA positive plasma samples. Then, relationships between plasma EBV viral load and clinicopathologic features of HL patients were analyzed. RESULTS: The positive rate of plasma EBV-DNA of HL patients was significantly higher than that of normal controls (53.3%vs26.4%, P=0.001). There was no significant difference about plasma EBV viral load between EBV-associated HL and EBV-DNA positive normal people (P=0.490). Looking at patients' characteristics, plasma EBV viral load in 10-20 years EBV-associated HL was higher than in EBV cases which were less than 10 years or more than 35 years (P=0.025). Furthermore, in EBV-associated HL, concentration of plasma EBV-DNA was significantly higher in advanced stage disease (stages III-IV; P=0.013), and with B-symptoms (P=0.020). CONCLUSION: EBV-DNA levels were associated with part of clinicopathologic features of cases. It was of practical use to screen HL. Further etiological studies appear warranted.