Ayshamgul Hasim

Overexpression of TLR3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma

AIM To investigate the expression of Toll-like receptor (TLR) 3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma (ESCC). METHODS Reverse transcription-polymerase chain reaction and immunohistochemistry were used to analyze the expression of TLR3, TLR4, TLR7 and TLR9 mRNA and protein in samples from 87 esophageal cancer patients consisting of both tumor and normal tissue. RESULTS A significant increase in TLR3, TLR4, TLR7 and TLR9 mRNA levels was detected in ESCC samples. Tumors exhibited high TLR protein expression, (70.1%, 72.4%, 66.7% and 78.2% for TLR3, TLR4, TLR7 and TLR9, respectively, P < 0.05). Nevertheless, a significant percentage of tumors also exhibited TLR4 expression in mononuclear inflammatory cells (48.3%) and TLR9 expression in fibroblast-like cells (60.9%). Tumors with high TLR3 expression in tumor cells or high TLR4 expression in mononuclear inflammatory cells were significantly associated with a higher probability of lymph node metastasis and increased depth of invasion. However, tumors with high TLR9 expression in fibroblast-like cells were associated with low probabilities of invasion and metastasis. There was no significant variation between the expression of TLR3, TLR4, TLR7 and TLR9 among different ethnic groups. CONCLUSION TLR3, TLR4, TLR7 and TLR9 expression appears important to the biological pathogenesis of ESCC. TLRs may represent therapeutic targets for ESCC.

Post-transcriptional and epigenetic regulation of antigen processing machinery (APM) components and HLA-I in cervical cancers from Uighur women.

Normal function of human leukocyte antigen class I (HLA-I) and antigen processing machinery (APM) proteins is required for T cell-mediated anti-tumor or antiviral immunity, whereas the tumor survival indicates a failure of the host in immune surveillance associated with the dysfunction in antigen presentation, mainly due to the deregulation in HLA-I and APM expression or function. The posttranscriptional regulation of HLA-I and APM expression may associate with epigenetic modifications in cancer development which was not described so far. Here we showed that the development of cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (CSCC) in Uighur women was accompanied with the partial or total loss of protein expression of HLA-I, ß2-m and APM components, including the transporter associated with antigen processing (TAP1/2), low molecular mass protein (LMP2, LMP7), endoplasmic reticulum aminopeptidase 1(ERAP1), chaperone molecules include calreticulin (CLR), calnexin (CNX) and ERp57, and this was proved again by analysis of transcription of the same genes in addition to three genes HLA-A, B and C coding for HLA-I. By bisulfite sequencing approach, we identified target CpG islands methylated at the gene promoter region of TAP1, TAP2, LMP7, tapasin and ERp57 in cervical carcinoma cells. Further analysis of CpG site specific methylation of these genes in cases of CSCC and CIN demonstrated an inverse correlation of altered CpG island methylation of TAP1, LMP7, and ERp57 with changes in protein expression. Moreover, promoter methylation of these genes was significantly higher in cases positive for human papillomavirus 16 (HPV 16) than negative ones. Our results suggested that epigenetic modifications are responsible for the aberrant expression of certain HLA-I and APM genes, and may help to understand unrevealed mechanisms of tumor escape from immune surveillance in cervical carcinogenesis.

Plasma free amino acid profiling of esophageal cancer using high-performance liquid chromatography spectroscopy

AIM To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects. METHODS Plasma samples from ESCC patients (n = 51) and healthy control adults (n = 60) were analyzed by high-performance liquid chromatography (HPLC). The ESCC patients included moderate/poorly-differentiation (n = 24), lymph node metastasis (n = 17) and clinical stage > Ib2 (n = 36). Partial least squares discriminant analysis was performed to demonstrate that the PFAA metabolic patterns enabled discrimination between ESCC patients and controls, and the Student t test was applied to assess significant differences in PFAA concentrations between the two groups. RESULTS There were significant differences in the PFAA profiles between controls and ESCC patients. Compared with healthy controls, the levels of Asp, Glu, Gly, His, Thr, Tau, Ala, Met, Ile, Leu, and Phe were decreased in ESCC patients, but Cys was increased. There exists a strong correlation between PFAA profiles and clinicopathological characteristics in ESCC patients. The levels of many PFAAs (i.e., Glu, Asp, Ser, Gly, Tau, Ala, Tyr, Val, Ile, and Leu) were related to pathological grading, lymph node metastasis, and ESCC clinical stage. Very good discrimination between ESCC patients and control subjects was achieved by multivariate modeling of plasma profiles. CONCLUSION HPLC-based plasma profiling analysis was shown to be an effective approach to differentiate between ESCC patients and controls. PFAA profiles may have potential value for screening or diagnosing ESCC.

Decreased blood riboflavin levels are correlated with defective expression of RFT2 gene in gastric cancer.

AIM To investigate the relationship between blood riboflavin levels and riboflavin transporter 2 (RFT2) gene expression in gastric carcinoma (GC) development. METHODS High-performance liquid chromatography was used to detect blood riboflavin levels in patients with GC. Real-time fluorogenic quantitative polymerase chain reaction and immunohistochemistry were used to analyze the expression of RFT2 mRNA and protein in samples from 60 GC patients consisting of both tumor and normal tissue. RESULTS A significant decrease in the RFT2 mRNA levels was detected in GC samples compared with those in the normal mucous membrane (0.398 ± 0.149 vs 1.479 ± 0.587; P = 0.040). Tumors exhibited low RFT2 protein expression (75%, 16.7%, 8.3% and 0% for no RFT2 staining, weak staining, medium staining and strong staining, respectively), which was significantly lower than that in the normal mucous membrane (10%, 16.7%, 26.7% and 46.7% for no RFT2 staining, weak staining, medium staining and strong staining, respectively; P < 0.05). Tumors with low RFT2 expression were significantly associated with tumor stage and histological grade. Moreover, a significantly decrease in Uyghur patients was observed compared with Han patients. However, other parameters-gender, tumor location and lymph node metastasis-showed no significant relationship with RFT2 expression. Blood riboflavin levels were reverse correlated with development of GC (1.2000 ± 0.97569 ng/mL in high tumor stage patients vs 2.5980 ± 1.31129 ng/mL in low tumor stage patients; P < 0.05). A positive correlation of plasma riboflavin levels with defective expression of RFT2 protein was found in GC patients (χ² = 2.619; P = 0.019). CONCLUSION Defective expression of RFT2 is associated with the development of GC and this may represent a mechanism underlying the decreased plasma riboflavin levels in GC.

Functional Role of NRF2 in Cervical Carcinogenesis.

Nuclear factor erythroid-2-related factor 2 (NFE2L2) is a transcription factor associated with resistance to chemotherapy and increased tumor growth. NRF2 is repressed by the inhibitor Keap1. The Keap1-NRF2 pathway is dysfunctional in multiple tumor types. Among Uighur women, the incidence of cervical squamous cell carcinoma (CSCC) and cervical intraepithelial neoplasia (CIN) was associated with elevated nuclear expression of NRF2 and decreased cytoplasmic expression of Keap1. Up-regulation of nuclear NRF2 was significantly associated with reduced cytoplasmic Keap1 expression. NRF2 positivity and Keap1 negativity were frequently associated with more advanced tumors (i.e., higher histological grade, lymph node involvement, and higher tumor stages) (p<0.05 for all). Methylated CpG islands in the Keap1 gene promoter in cervical cancer tissue were identified using MassARRAY. Moreover, promoter hypermethylation of this gene was significantly associated with decreased protein expression and increased nuclear NRF2 expression in cervical cancer tissues. Overexpression and knockdown of NRF2 in CSCC cell lines showed that NRF2 promotes proliferation, inhibits apoptosis, and enhances migration and invasion. These studies support the concept that epigenetic changes regulate expression of Keap1 in cervical cancer tissues. The association of NRF2 expression with aggressive tumor behavior suggests that NRF2 may be a marker of poor prognosis in patients with cervical cancer.

Association of the Plasma and Tissue Riboflavin Levels with C20orf54 Expression in Cervical Lesions and Its Relationship to HPV16 Infection

Riboflavin deficiency can cause a variety of metabolic problems that lead to skin and mucosal disorders. Limited evidence suggests that high intake of riboflavin may reduce overall risks of cancer. However, association of this deficiency with cervical cancer and precancerous lesions are still not definitively known. In this study, we characterized the relationship between plasma and tissue riboflavin levels and C20orf54 protein expression in patients with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (CSCC) as well as the relationship of these levels with human papillomavirus virus 16, 18 (HPV16/18) infections. High-performance liquid chromatography (HPLC) was used to measure blood riboflavin levels in patients with CIN and CSCC, and an enzyme-linked immunosorbent assay (ELISA) was used to determine tissue riboflavin levels in patients with CSCC and matched normal mucous epithelia. The expression of C20orf54 in fresh CSCC and matched tissues were detected by qRT-PCR and western blot, respectively. And it was further confirmed by immunohistochemistry (IHC) with formalin-fixed, paraffin-embedded CIN and CSCC. An HPV genotyping chip was used to analyze HPV infection and typing. The results showed that patients with CIN and CSCC had decreased plasma riboflavin levels as compared with normal controls. There was also significantly decreased riboflavin in tissues from CSCC patients, when compared with normal cervical epithelia. C20orf54 expression were significantly up-regulated in CSCC compared to matched control on both mRNA and protein level. Tissue riboflavin levels were significantly lower in HPV16/18 positive tissue compared with HPV16/18-negative tissue, and an inverse association was found between tissue riboflavin levels and C20orf54 mRNA and protein expression in CSCC. Additionally, C20orf54 was significantly correlated with tumor stages. In conclusion, C20orf54 tend to play a protective role in Uyghur cervical carcinogenesis of which modulating riboflavin absorption, and it is also related with HPV infection.

Metabolomic profiling reveals potential biomarkers in esophageal cancer progression using liquid chromatography-mass spectrometry platform

Esophageal cancer (EC) is one of the most common malignancies with poor prognosis. Metabolomics has been shown to be a powerful approach to discover the potential biomarkers for cancer diagnosis and prognosis. The goal of this study is to screen potential biomarkers for early diagnosis and prognosis. In this study, 40 tissue samples and the corresponding control samples from the same esophageal squamous cell carcinoma (ESCC) patients were analyzed by liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. 20 potential diagnostic biomarkers were selected. Moreover, 9 metabolites were found to be closely correlated with the pathological feature such as local invasion, lymphatic metastasis and postoperative survival time. Glutamate was correlated with local invasion of tumor, and oleic acid, LysoPC(15:0), uracil, inosine and choline were closely related with the lymphatic metastasis, while glutamine, kynurenine, serine and uracil were related with postoperative survival time. The results indicated that the potential biomarkers discovered by metabolomics could reflect the metabolic characterization of ESCC, and offers a novel approach for early diagnosis, assessment and prognosis of the disease.

Epigenetic Changes within the Promoter Regions of Antigen Processing Machinery Family Genes in Kazakh Primary Esophageal Squamous Cell Carcinoma

The esophageal squamous cell carcinoma (ESCC) is thought to develop through a multi-stage process. Epigenetic gene silencing constitutes an alternative or complementary mechanism to mutational events in tumorigenesis. Posttranscriptional regulation of human leukocyte antigen class I (HLA-I) and antigen processing machinery (APM) proteins expression may be associated with novel epigenetic modifications in cancer development. In the present study, we determined the expression levels of HLA-I antigen and APM components by immunohistochemistry. Then by a bisulfite-sequencing PCR (BSP) approach, we identified target CpG islands methylated at the gene promoter region of APM family genes in a ESCC cell line (ECa109), and further quantitative analysis of CpG site specific methylation of these genes in cases of Kazakh primary ESCCs with corresponding non-cancerous esophageal tissues using the Sequenom MassARRAY platform. Here we showed that the development of ESCCs was accompanied by partial or total loss of protein expression of HLA-B, TAP2, LMP7, tapasin and ERp57. The results demonstrated that although no statistical significance was found of global target CpG fragment methylation level sof HLA-B, TAP2, tapasin and ERp57 genes between ESCC and corresponding non-cancerous esophageal tissues, there was significant differences in the methylation level of several single sites between the two groups. Of thesse only the global methylation level of LMP7 gene target fragments was statistically higher (0.0517±0.0357) in Kazakh esophageal cancer than in neighboring normal tissues (0.0380±0.0214, p<0.05). Our results suggest that multiple CpG sites, but not methylation of every site leads to down regulation or deletion of gene expression. Only some of them result in genetic transcription, and silencing of HLA-B, ERp57, and LMP7 expression through hypermethylation of the promoters or other mechanisms may contribute to mechanisms of tumor escape from immune surveillance in Kazakh esophageal carcinogenesis.

Expression, prognosis and functional role of Thsd7a in esophageal squamous cell carcinoma of Kazakh patients, Xinjiang

Thsd7a (Thrombospondin type 1 domain containing 7a) is a critical transmembrane protein. Studies have indicated that Thsd7a was associated with cytoskeletal organization, cell migration and filopodia formation. However, the involvement of Thsd7a remains elusive in human Esophageal Squamous Cell Carcinoma (ESCC). Consequently, immunohistochemistry and reverse transcription-polymerase chain reaction were utilized to study the correlation between the expression of Thsd7a and clinical-pathological characteristics. The influence of Thsd7a on apoptosis, cell proliferating activity, cell cycle, migratory and invasive capacity was determined in Eca 109 and EC 9706 cell lines in vitro. And the influence on proliferating activity was testified using naked mice model in vivo. In addition, the potential molecular mechanism was tested by microarray. It was discovered that there is a certain correlation between Thsd7a and the Kazakh ESCC. By knocking out Thsd7a, the invasion, migration and proliferation could be decreased. And it could also arrest the cell cycle at G1 phase and increase the apoptosis rate. It was further verified that Thsd7a had obvious effect on proliferation in naked mice with xenograft of Eca109 cells. Finally, it was uncovered by microarray analysis that a variety of tumor genes and pathways related to Thsd7a. Together, it was demonstrated that Thsd7a might have a certain degree of carcinogenesis in ESCC.Thsd7a (Thrombospondin type 1 domain containing 7a) is a critical transmembrane protein. Studies have indicated that Thsd7a was associated with cytoskeletal organization, cell migration and filopodia formation. However, the involvement of Thsd7a remains elusive in human Esophageal Squamous Cell Carcinoma (ESCC). Consequently, immunohistochemistry and reverse transcription-polymerase chain reaction were utilized to study the correlation between the expression of Thsd7a and clinical-pathological characteristics. The influence of Thsd7a on apoptosis, cell proliferating activity, cell cycle, migratory and invasive capacity was determined in Eca 109 and EC 9706 cell lines in vitro. And the influence on proliferating activity was testified using naked mice model in vivo. In addition, the potential molecular mechanism was tested by microarray. It was discovered that there is a certain correlation between Thsd7a and the Kazakh ESCC. By knocking out Thsd7a, the invasion, migration and proliferation could be decreased. And it could also arrest the cell cycle at G1 phase and increase the apoptosis rate. It was further verified that Thsd7a had obvious effect on proliferation in naked mice with xenograft of Eca109 cells. Finally, it was uncovered by microarray analysis that a variety of tumor genes and pathways related to Thsd7a. Together, it was demonstrated that Thsd7a might have a certain degree of carcinogenesis in ESCC.

Plasma amino acid profiling of cancer patients with abnormal savda based on high-performance liquid chromatography.

OBJECTIVE To investigate metabolic signatures in plasma of cancer patients with abnormal Savda using plasma-free amino acid profiles, and to evaluate the diagnostic potential of these profiles for the detection and explanation of the mechanisms of different symptoms in traditional Uyghur medicine. METHODS Plasma samples from cancer patients with abnormal Savda (n = 85) or non-abnormal Savda (n = 105) and a healthy control group (n = 65) were analyzed using high-performance liquid chromatography (HPLC). Orthogonal projection to latent structures with discriminant analysis was used for the classification and prediction of abnormal Savda, and spectral profiles were subjected to Students t-tests to assess statistical significance. RESULTS Compared with the healthy group, the levels of aspartic acid, glutamate, glycine, histidine, arginine, threonine, alanine, proline, methionine, isoleucine, leucine and phenylalanine decreased significantly in plasma of cancer patients with abnormal Savda (all P < 0.05). Serine, cystine, tyrosine, valine and lysine levels showed no significant differences (all P > 0.05). Compared with non-abnormal Savda syndrome patients, abnormal Savda syndrome patients showed high concentrations of glutamate, serine, valine, isoleucine, leucine and phenylalanine (all P < 0.05). The remaining plasma amino acids showed no significant differences (all P > 0.05). CONCLUSION Plasma-free amino acid profiling has the potential to assist in understanding and determining abnormal Savda. A HPLC-based metabonomic platform could be a powerful tool for the classification of symptoms in traditional medicine.