Endogenous n-3 polyunsaturated fatty acids protect against imiquimod-induced psoriasis-like inflammation via the IL-17/IL-23 axis.

The beneficial effects of n-3 polyunsaturated fatty acids (PUFAs) on psoriasis have been reported in rats, mice and humans, but the specific mechanisms involved have not been well defined. The present study utilized the fat-1 mouse, a transgenic model that can endogenously convert n-6 FAs into n-3 PUFAs, to directly determine if the outcomes of psoriasis were correlated with n-3 PUFAs. Wild-type (WT) and fat-1 mice, which were treated daily with imiquimod (IMQ) cream or control cream on the shaved right ear and dorsal skin, were fed the same diet. The severity of inflammation of the ear and dorsal skin was scored according to the clinical Psoriasis Area and Severity Index (PASI) and epidermal hyperplasia was measured by H&E staining. The expression of inflammatory factors in the epidermis was analyzed by immunohistochemical analysis. Flow cytometry and an enzyme-linked immunosorbent assay were used to measure the differences in the content of inflammatory factors in the blood serum and to determine which of CD4+ T cells were present in the spleen between IMQ-induced fat-1 mice and WT mice. Fat-1 IMQ-induced mice exhibited significantly lower levels of inflammatory cell-like T helper 17 cells (Th17 cells) and higher levels of regulatory T cells (Treg cells) in the spleen as compared with the WT IMQ-induced mice. n-3 fatty acids stimulated Th17 cells to produce lower levels of inflammatory factors, including interleukin (IL)-17, IL-22, IL-23 and stimulated Treg cells to produce higher anti-inflammatory factors, such as Foxp3. In conclusion, the present study provides further insight into the mechanisms involved in preventing inflammation in psoriasis-like mice by n-3 PUFAs using a fat-1 transgenic mouse model.

Macrophage migration inhibitory factor contributes angiogenesis by up-regulating IL-8 and correlates with poor prognosis of patients with primary nasopharyngeal carcinoma.

BACKGROUND AND OBJECTIVES: We aim at the association of macrophage migration inhibitory factor (MIF) with neovascularization and survival of nasopharyngeal carcinoma (NPC), and determine whether MIF is a valuable prognostic predictor for NPC patients. METHODS: One hundred and forty one cases of NPC and 25 normal tissues of nasopharynx were collected. The expression of MIF and interleukin 8 (IL-8) was evaluated in tissues microarray by immunostaining. Intratumoral microvessel density (IMD) in relation to immunostainings and clinicopathological factors were analyzed statistically as well as the follow-up data of patients. RESULTS: High-expression of both MIF (69.5%) and IL-8 (56.0%) were significantly associated with increased microvessels and lymph node metastasis. High-expression of MIF, IL-8 and higher level of IMD were correlated with either patients' overall survival or disease-specific survival in univariate analysis, but only angiogenesis and lymph node status exhibited in relation to survival of patients as independent prognostic factor of NPC by multivariate analysis. In addition, high-expression of MIF and higher level of IMD were closely associated with locoregional failure of NPC patients. CONCLUSIONS: MIF may contribute to lymph node metastasis in NPC by inducing angiogenesis through the way of upregulation of IL-8 expression in an autocrine EBV-independent pathway.

[Correlation analysis between multi-slice CT perfusion imaging and microvessel density in ovarian tumors].

OBJECTIVE: To analyze the correlation between the perfusion data and microvessel density (MVD) in ovarian tumors, and investigate the hemodynamic features of the tumors in terms of anatomy and functional CT imaging. METHODS: Six patients with surgically confirmed benign ovarian tumors and 6 with malignant ovarian tumors underwent multi-slice CT perfusion imaging to acquire the perfusion parameters including perfusion, PEI, TTP, BV peak enhancement image(PEI), time to peak(TTP) and blood volume(BV). The tumors were stained and counted by Immunohistochemical staining of the microvessels in the tumor was performed to detect the MVD. RESULTS: s The time-density curves of the benign ovarian tumors increased slowly, reaching the peak at 40 s; the curves of the malignant tumors rose rapidly and continuously and reached the peak at 25 s. The differences in the perfusion data (PEI, TTP, BV) were statistically significant between the benign and malignant tumors (P<0.05). The MVD of the malignant tumors was significantly greater than that of the benign tumors (P<0.05). The mean BV of the malignant ovarian tumor was positively correlated to MVD (r=0.786, P<0.05). CONCLUSION: Multi-slice spiral CT perfusion imaging can provide accurate enhancement data of the ovarian tumors and helps in the diagnosis and differential diagnosis of the ovarian tumors by presenting the changes of the hemodynamic features in the tumors.

[Atypical magnetic resonance imaging vs pathological findings of leiomyoma in the female reproductive system].

OBJECTIVE: To investigate magnetic resonance imaging (MRI) findings of the atypical leiomyoma in the female reproductive system in comparison with the pathological features of the neoplasms. METHODS: A retrospective analysis of the MRI findings and the pathological features was conducted in 24 cases of atypical leiomyoma involving the female reproductive system. RESULTS: Atypical leiomyomas were displayed by MRI as solid tumor mass surrounded by cystic degeneration, pseudotumors, or solid mass with homogeneous signal intensity. Intrauterine lesions were found in 19 cases, involving the subserosal layer (n=11), intramural region (n=4), broad ligament (n=3), cervix (n=2), submucous layer (n=2), vagina (n=1), and the ovary (n=1). Except for two cases with submucous lesions shown as solid mass, all the cases had lesions appearing as solid cystic mass, whose solid part showed hypo or isointense signals on T1WI and moderate hyperintense signals on T2WI, with heterogeneous enhancement after contrast agent injection. Tumor cell and interstitial cell swelling, vascular hyalinosis, hyalinosis, myxoedema, cystic degeneration, and hemorrhage were found in the lesions. CONCLUSION: Leiomyoma can occur at almost any site in the female reproductive system, and atypical leiomyoma usually are shown as solid cystic mixed mass in the pelvic cavity. Evaluation of the relationship between the solid mass and cystic portion and observation for the presence of low signal on T2WI may help in the diagnosis of atypical leiomyoma.

Epstein-Barr virus infection in precursor lesions of nasopharyngeal carcinoma.

BACKGROUND & OBJECTIVE: The infiltrating neoplastic cells within early-stage nasopharyngeal carcinoma (NPC) are consistently infected with Epstein-Barr virus (EBV). The precursor lesions could often be found in paracancerous epithelium of early-stage NPC. This study was to investigate the role of EBV infection and the intrahost evolution of EBV genotype developed in nasopharyngeal carcinogenesis through detection of EBV harboring in precursor lesions. METHODS: EBV-encoded RNA (EBER) in 15 cases of early-stage NPC biopsy tissue was detected by nucleic acid in situ hybridization. EBV type and latent membrane protein 1 (LMP1) EBV strain in precursor lesions and carcinoma nests were detected by nested polymerase chain reaction (PCR). DNA sequencing of the representative PCR products of carboxyl-terminus of LMP1 gene was analyzed by using four-colored fluorescence terminator sequencing technique. RESULTS: Most infiltrating carcinoma cells of all 15 cases of NPC showed EBER-positive. EBER-positive abnormal epithelial cells and/or infiltrating lymphocytes were found in 14 of 15 cases of precursor lesion. Single A-type EBV was detected in 9 of 11 available DNA samples of carcinoma nest and 9 of 10 available DNA samples of precursor lesion. The carboxyl-terminus of EBV LMP1 gene was detected in all 15 DNA samples of carcinoma nest, among which 14 were single 30-bp deleted LMP1 (del-LMP1) EBV infection and 1 was coinfection of wild-type LMP1 (wt-LMP1) EBV strain and del-LMP1 EBV strain. Among the 11 available DNA samples of precursor lesion suitable for carboxyl-terminus amplification, 5 were coinfection of wt-LMP1 and del-LMP1 EBV, 4 were single del-LMP1 EBV infection, 1 was single wt-LMP1 EBV infection, and 1 showed negative reaction. The DNA sequence of the carboxyl-terminus of wt-LMP1 gene was identical with that of B95-8 cells, while that of del-LMP1 gene had a 30-bp deletion (codon: 346-355) and 4 missense point mutations (codon: 334, 335, 338, and 366). CONCLUSION: EBV infection in nasopharyngeal epithelial cells is a preinvasive event of carcinogenesis of NPC, and the intrahost evolution of EBV genotype would take place during nasopharyngeal carcinogenesis.

[Study of sequence variations of Epstein-Barr virus LMP1 gene in nasopharyngeal carcinoma].

OBJECTIVE: To detect the sequence variations frequently found within the N- and C-terminal regions of Epstein-Barr virus (EBV) LMP1 gene in nasopharyngeal carcinoma (NPC) and to study the underlying mechanisms. METHODS: Fresh tumor tissues were sampled from 63 patients with untreated NPC encountered in Affiliated Tumor Hospital of Sun Yat-sen University, Guangzhou. The N-terminal region of EBV LMP1 gene was amplified with nested polymerase chain reaction (PCR), followed by XhoI enzyme digestion. Nested PCR was also employed to detect the 30 base pairs deletion within the C-terminal region. Four-colored fluorescence terminator sequencing method was applied for bi-directional solid-phase sequencing of the 8 representative PCR products in 4 cases of NPC. The DNA sequence within the N- and C-terminal regions of LMP1 gene was then analyzed. RESULTS: There were 4 patterns of sequence variations, namely, wt-XhoI/wt-LMP1 (4 cases, 6.3%), wt-XhoI and XhoI-loss/del-LMP1 (4 cases, 6.3%), wt-XhoI/del-LMP1 (5 cases, 7.9%) and XhoI-loss/del-LMP1 (50 cases, 79.5%), detected in the 63 studied cases. Sequence analysis showed that the EBV LMP1 gene had underwent non-synonymous and synonymous substitutions, as compared with the prototype of B95-8 cells. The ratio of non-synonymous to synonymous substitutions was 2.25. CONCLUSIONS: XhoI-loss/del-LMP1 is the predominant sequence variation pattern of EBV LMP1 gene in NPC from Guangzhou. The XhoI-loss variation seems to develop on top of del-LMP1. When compared with the EBV LMP1 gene in peripheral blood B-lymphocytes of virus carriers and in preinvasive epithelial lesions (reported previously), it is likely that the sequence variation patterns of LMP1 gene may represent 4 different phases of intrahost evolution of EBV during nasopharyngeal carcinogenesis.

[Comparison of the Epstein-Barr virus infection and 30 bp-deleted LMP1 gene among 4 histologic types of nasopharyngeal carcinoma].

OBJECTIVE: To compare the Epstein-Barr virus (EBV) infection rates and the frequencies of wt-LMP1 and del-LMP1 EBV variants detected singly or dually among the four types of nasopharyngeal carcinoma (NPC) and to illustrate the possible role of del-LMP1 gene in nasopharyngeal carcinogenesis. METHODS: EBER in situ hybridization was performed in 117 NPCs, including 48 non-keratinizing carcinomas (NKCs), 25 keratinizing squamous cell carcinomas (KSCCs), 5 adenosquamous carcinomas (ASCs), 6 mucoepidermoid carcinomas (MECs) and 33 adenocarcinomas (ACs). Nested PCR for demonstration of EBV LMP1 gene was performed on the tissue samples collected from 99 EBER-positive carcinoma cases and the peripheral blood mononuclear cells (PBMCs) of 53 healthy adults (HAs). RESULTS: As indicated by EBER in-situ hybridization, the EBV infection rates in both of 48 NKCs and 25 KSCCs were 100%; and the infection rates of 11 ASCs/MECs and 33 ACs were 9/11 and 51.5% (17/33), respectively. Worthy to note was that most of the NKC cells were EBER-positive while only a small number of EBER-positive neoplastic cells could be found in 17 ACs. The percentage of del-LMP1 EBV variant detected singly in NKCs (85.4%, 41/48) was not only significantly higher than that in PBMCs of 46 HAs (8.7%, 4/46) but also significantly higher than those detected in KSCCs (16.0%, 4/25). The dual infection rate of wt-LMP1 and del-LMP1 variants detected in KSCCs (56.0%, 14/25) was significantly higher than that of NKCs (12.5%, 6/48). The majority of the EBV detected in AC tissues (12/17) and HAs' PBMCs (34/46, 73.7%) were of dual wt-LMP1 and del-LMP1 variants. CONCLUSIONS: The EBV infection rates are significantly different among 3 major histological categories, namely, NKC/KSCC, ASC/MEC and AC. Though NKCs and KSCCs are always consistently associated with EBV, the single del-LMP1 EBV variant detected in NKCs is predominant over that in KSCCs and most of the KSCCs contain dual wt-LMP1 and del-LMP1 EBV variants. The EBV of the del-LMP1 variant might play a crucial role in carcinogenesis of NKC.

[Primary adenoid cystic carcinoma of the nasopharynx and its relation to Epstein-Barr virus infection].

OBJECTIVE: To investigate the clinicopathologic characteristics of primary nasopharyngeal adenoid cystic carcinoma (NPACC) and its relation to Epstein-Barr virus (EBV) infection in Guangzhou where is a high-incidence area of EBV-associated nasopharyngeal carcinoma (NPC). METHODS: 17 cases of NPACC with clinical record and biopsy samples were collected in Guangzhou and their clinical manifestations were reviewed. Besides HE, Alcian blue and PAS, LSAB immunohistochemistry was performed for detecting the expression of a variety of epithelial markers, CD21 and EBV encoded LMP1. EBV encoded early RNAs (EBER) was detected by using in-situ hybridization. Nested PCR was applied for studying the presence of EBV W-fragment in tissues. RESULTS: The ratio of male to female was 7:10. The patients' age ranged from 30 to 63 years, and the median age was 46 years. 14 out of 17 tumors showed markedly local aggressive growth, presenting as T3 or T4. However, only 1 patient had metastasis of an ipsilateral cervical lymph node. The majority of neoplastic cells were basal-cell like in shape and with scanty cytoplasm and a deeply stained nucleus. Intercellular hyaline or mucinous substance was always present in between the carcinoma cells. Cribriform structure formed by the neoplastic cells could be found in 16 out of these 17 biopsies. The NPACC always express the wide-spectrum cytokeratin and the epithelium membrane antigen. Only a few or a small number of carcinoma cells showed nuclear EBER-signals in 9 cases (9/17). Concurrently, these 9 NPACCs showed a 192 bp W-fragment positive band on electrophoresis gel by nested PCR. LMP1 expression had been found in 5 out of the 9 NPACCs (55.6%) accompanying with EBER-positive carcinoma cells. The EBER-positive infiltrating lymphocytes could also be found in the stroma of 3 out of the 9 EBER-stained NPACC slides. All the tumor cells, including the EBER-positive cell of the 17 NPACCs showed no CD21 expression. CONCLUSIONS: The female is predominant over the male in development of NPACC, which often accompanied with a markedly invasive capacity at the nasopharynx and its neighboring sites. Only a small number of tumor cells, nearly a half of the studied cases were infected with EBV. Therefore, it's postulated that there seems no close relation present between NPACC and EBV infection.

[Advancement of studying the biological characteristics of nasopharyngeal carcinogenesis].

This review is to summarize the main achievements of studying the biological characteristics of nasopharyngeal carcinogenesis performed by the authors' research team and the recent advancement in this field during the past 5 years as well as to explain the authors' viewpoints concerning the nasopharyngeal carcinogenesis. In order to study the nasopharyngeal carcinogenesis, more than 20,000 nasopharyngeal carcinoma biopsies and more than 600 nasopharyngeal biopsies of Epstein-Barr virus seropositive persons who had been got follow-up over 12 years, were collected. In addition, nude mice and cell lines were also to be utilized. Besides histopathological staining, methods of molecular biology, including in-situ hybridization, PCR etc. were applied. Up to date, 26 papers concerning this subject had been formally published in the medico-biological journals at home and abroad. The results and conclusions were as follows. (1) The squamous metaplasia, epithelial dysplasia, carcinoma in-situ and microinvasive carcinoma are the morphogenetic sequence found in nasopharyngeal carcinogenesis. (2) This morphogenetic sequence is frequently observed in a restricted area of nasopharyngeal mucosal epithelium, representing as an appearance of field carcinogenesis. (3) EB virus may play a critical role in nasopharyngeal carcinogenesis, since EB virus DNA and small RNAs could be detected in epithelial dysplasia first and several viral encoded products, especially LMP1, might be expressed in dysplasia, carcinoma in-situ and microinvasive carcinoma. (4) The multigenic mechanisms, including interactions between EB viral genes encoded products and the products abnormally expressed step by step from genes related to cell-cycle regulation, are the molecular events involved in nasopharyngeal carcinogenesis. (5) The cellular immunity of individuals should also be considered as an important factor influencing nasopharyngeal carcinogenesis, because EB virus specific cytotoxic T-lymphocytes could not only be observed in carcinoma nests but also detected in peripheral blood.