Genetic and epigenetic alterations of the blood group ABO gene in oral squamous cell carcinoma

Mixed-field ABO front typing as an early sign of disease recurrence in ABO-matched stem cell transplantation

ABO group testing is critical for allogeneic stem cell transplantation because mismatches can cause both transfusion and engraftment challenges. Even with ABO-matched donor-recipient pairs, ABO group determination may provide valuable insight into allograft status. Herein, we report a case of a 76-year-old female patient with myeloid neoplasm who underwent ABO-matched stem cell transplantation and in whom mixed-field ABO antigen expression during routine follow-up testing post-transplantation was the first sign of a change in transplant graft status; the mixed-field findings pre-dated changes in formal chimerism testing. This case underscores the potential of mixed-field ABO typing as an early indicator of disease recurrence in ABO-matched stem cell transplants and suggests that, in such cases, more sensitive forms of chimerism testing and/or closer monitoring for disease recurrence, particularly in the clinical setting of myeloid neoplasms, may be warranted.

Role of MiRNA in the Regulation of Blood Group Expression

Background

MicroRNAs (miRNAs) are small, endogenous non-coding RNA molecules that inhibit gene expression through either destabilization of the target mRNA or translational repression. MiRNAs recognize target sites, most commonly found in the 3'-untranslated regions of cognate mRNAs. This review aims to provide a state-of-the-art overview of the role of miRNAs in the regulation of major blood group antigens such as ABH as well as cancer-specific glycans.

Summary

Besides their known roles in the control of developmental processes, proliferation, apoptosis, and carcinogenesis, miRNAs have recently been identified to play a regulatory role during erythropoiesis and blood group antigen expression. Since only little is known about the function of the red cell membrane proteins carrying blood group antigens, it is of great interest to shed light on the regulatory mechanisms of blood group gene expression. Some carrier proteins of blood group antigens are not restricted to red blood cells and are widely expressed in other bodily fluids and tissues and quite a few play a crucial role in tumor cells, as either tumor suppressors or promoters.

Key Message

All available data point at a tremendous physiological as well as pathophysiological relevance of miRNAs in context of blood group regulation. Furthermore, miRNAs are involved in the regulation of pleiotropic genetic pathways such as hematopoiesis and tumorigenesis and thus have to be studied in future research on this subject.

Review of ABO Expression and Variations based on Transcriptional Regulation of the ABO Blood Group Gene

Background and Summary

We review the transcriptional regulation of ABO expression and discuss variants in the promoter and erythroid cell-specific regulatory region in individuals with weak ABO phenotypes such as Bm, Am, B3, and A3. We also review the molecular mechanisms responsible for variations in ABO expression in development and disease including the cell type-specific expression of ABO during erythroid cell differentiation, and reduction of A- or B-antigens in cancer cells or on red blood cells in patients with leukemia. Although the relationship between ABO blood group antigens and diseases has been characterized, the physiological significance of the ABO blood group system remains unclear.

Key Messages

This review discusses accumulated knowledge of the ABO gene regulation and potential reasons for conservation of ABO during evolution.

CEBPA double mutations associated with ABO antigen weakness in hematologic diseases

ABSTRACT

ABO antigen weakness is rarely observed in ABO typing for transfusion. Hematologic diseases and associated gene mutations have been suggested as potential causes of this phenomenon, yet the precise etiology has not been elucidated. Through ABO typing and genetic analysis data conducted over 7 years, we have reconfirmed the association between ABO antigen weakness and hematologic diseases, especially acute myeloid leukemia (odds ratio [OR], 2.55; 95% confidence interval [CI], 1.12-5.83) and myelodysplastic syndrome (OR, 6.94; 95% CI, 2.86-16.83), and discovered previously unidentified candidate genes, CEBPA (OR, 43.70; 95% CI, 18.12-105.40), NRAS (OR, 3.37; 95% CI, 1.46-7.79), U2AF1 (OR, 8.12; 95% CI, 2.86-23.03), and PTPN11 (OR, 4.52; 95% CI, 1.51-13.50), seemingly associated with this phenomenon. Among these, CEBPA double mutations displayed a significant association, with ABO antigen weakness being observed in 20 of the 25 individuals (80.0%) possessing these mutations. From this study, new factors associated with ABO antigen weakness have been identified.

Association between ABO blood type and type I endometrial cancer: a retrospective study

This study aimed to assess the association between ABO blood type and incident of type I endometrial cancer (EC), as well as the stage and differentiation. 213 patients with type I EC and 300 healthy controls were included. As a result, the frequencies of A, B, O, and AB blood types among patients with type I EC were 51 (23.9%), 59 (27.7%), 93 (43.7%) and 10 (4.7%), respectively. There were no significant differences in age, body mass index, and other baseline covariates between groups of ABO blood types (p > .05). Logistic regression model showed that women with blood type O was more likely to develop type I EC than those with type A (odds ratio (OR): 1.66, 95% confidence interval (CI): 1.05-2.63). However, there was no significant association of ABO blood type with stage and differentiation of type I EC (p > .05). In conclusion, blood type O was the most prevalent ABO blood type among patients with type I EC and was associated with increased risk of type I EC, while ABO blood type was not significantly associated with stage or differentiation of type I EC.IMPACT STATEMENTWhat is already known on this subject? Previous studies have produced inconsistent findings on association of ABO blood type with EC. Those studies also did not explore the relationship between ABO blood type and stage or differentiation of type I EC.What the results of this study add? The present study showed that women with blood type O was more likely to develop type I EC than those with type A and there was no significant association of ABO blood type with stage or differentiation of type I EC.What the implications are of these findings for clinical practice and/or further research? Gynaecologists should pay more attention to women with blood type O, who should undergo more active EC screening.

My 20 years together with Journal of Oral Pathology and Medicine

Shan Gao has served at Journal of Oral Pathology and Medicine (JOPM) for 20 years, and currently as Associate Editor of JOMP, Beijing, China. After he finished his 8 year education in Stomatology for both bachelor and master degrees, he started 10 years of clinic practice in Endodontics and Oral Medicine in China, followed by 12 years basic research work in Molecular Biology, including 3 years for a PhD degree in Denmark and 10 years industry experience in a leading RNAi therapeutic company in China. During those years of experience, he built up a close relationship with Oral Pathology and Oral Medicine. It is great opportunity to introduce his story together with JOPM, accompanying with his personal research experience, at the moment of the 50th Anniversary of JOPM.

ABO blood groups and expression of blood group antigens of epithelial ovarian cancer in Chinese women

BACKGROUND

ABO blood groups has been associated with risk of several cancers; however, the results for an association with ovarian cancer are inconsistent and little is known about the expression of histo-blood group (ABH) antigens and ABO gene in ovarian tumor tissues.

METHODS

To assess the impact of genotype-derived ABO blood types on the risk of EOC, we conducted a case-control study in 1,870 EOC and 4,829 controls. Expression of A and B antigen in 70 pairs of ovarian tumor tissues and adjacent normal tissues were detected by immunohistochemistry. Gene expression and DNA methylation profiling was conducted in ovarian tumor tissues.

RESULTS

We identified that blood group A was associated with increased risk for EOC compared to blood group O (OR = 1.18, 95% CI = 1.03-1.36, p = 0.019). Increased frequency of aberrant expression of histo-blood group antigens was observed in patients with blood group A (76.5%) compared to patients with blood group O (21.1%) and B (5.0%) by immunohistochemistry (p < 0.001). ABO gene expression was down-regulated in ovarian tumor tissues compared with paired adjacent normal tissues (p = 0.027). In addition, ABO gene expression was positively correlated with NFYB (r = 0.38, p < 0.001) and inversely correlated with DNA methylation level of four CpG sites on ABO gene (cg11879188, r = - 0.3, p = 0.002; cg22535403, r = - 0.30, p = 0.002; cg13506600, r = - 0.22, p = 0.025; cg07241568, r = - 0.21, p = 0.049) in ovarian tumor tissues.

CONCLUSION

We identified blood group A was associated with increased EOC risk in Chinese women and provided the clues of the possible molecular mechanisms of blood group A related to ovarian cancer risk.

Head and Neck Cancers Are Not Alike When Tarred with the Same Brush: An Epigenetic Perspective from the Cancerization Field to Prognosis

Simple Summary

Squamous cell carcinomas affect different head and neck subsites and, although these tumors arise from the same epithelial lining and share risk factors, they differ in terms of clinical behavior and molecular carcinogenesis mechanisms. Differences between HPV-negative and HPV-positive tumors are those most frequently explored, but further data suggest that the molecular heterogeneity observed among head and neck subsites may go beyond HPV infection. In this review, we explore how alterations of DNA methylation and microRNA expression contribute to head and neck squamous cell carcinoma (HNSCC) development and progression. The association of these epigenetic alterations with risk factor exposure, early carcinogenesis steps, transformation risk, and prognosis are described. Finally, we discuss the potential application of the use of epigenetic biomarkers in HNSCC.

Abstract

Head and neck squamous cell carcinomas (HNSCC) are among the ten most frequent types of cancer worldwide and, despite all efforts, are still diagnosed at late stages and show poor overall survival. Furthermore, HNSCC patients often experience relapses and the development of second primary tumors, as a consequence of the field cancerization process. Therefore, a better comprehension of the molecular mechanisms involved in HNSCC development and progression may enable diagnosis anticipation and provide valuable tools for prediction of prognosis and response to therapy. However, the different biological behavior of these tumors depending on the affected anatomical site and risk factor exposure, as well as the high genetic heterogeneity observed in HNSCC are major obstacles in this pursue. In this context, epigenetic alterations have been shown to be common in HNSCC, to discriminate the tumor anatomical subsites, to be responsive to risk factor exposure, and show promising results in biomarker development. Based on this, this review brings together the current knowledge on alterations of DNA methylation and microRNA expression in HNSCC natural history, focusing on how they contribute to each step of the process and on their applicability as biomarkers of exposure, HNSCC development, progression, and response to therapy.

A cell-specific regulatory region of the human ABO blood group gene regulates the neighborhood gene encoding odorant binding protein 2B

The human ABO blood group system is of great importance in blood transfusion and organ transplantation. ABO transcription is known to be regulated by a constitutive promoter in a CpG island and regions for regulation of cell-specific expression such as the downstream + 22.6-kb site for epithelial cells and a site in intron 1 for erythroid cells. Here we investigated whether the + 22.6-kb site might play a role in transcriptional regulation of the gene encoding odorant binding protein 2B (OBP2B), which is located on the centromere side 43.4 kb from the + 22.6-kb site. In the gastric cancer cell line KATOIII, quantitative PCR analysis demonstrated significantly reduced amounts of OBP2B and ABO transcripts in mutant cells with biallelic deletions of the site created using the CRISPR/Cas9 system, relative to those in the wild-type cells, and Western blotting demonstrated a corresponding reduction of OBP2B protein in the mutant cells. Moreover, single-molecule fluorescence in situ hybridization assays indicated that the amounts of both transcripts were correlated in individual cells. These findings suggest that OBP2B could be co-regulated by the + 22.6-kb site of ABO.

Is ABO blood group a risk or prognostic factor for patients with endometrioid endometrial cancer? A retrospective analysis in Germany

BACKGROUND

A relationship is known to exist between gastric and pancreatic cancers and ABO antigens, caused by various immune modulations related to the ABO blood group of the patient. A similar relationship with regard to gynaecological cancers remains controversial.

MATERIALS AND METHODS

Patients who underwent surgery for endometrioid endometrial cancer in International Federation of Gynaecology and Obstetrics (FIGO) stage I, II, III or IV from 2006 to 2018 were identified. The research explored the existence of a relationship between the patients' blood group or Rhesus factor and the incidence of endometrial cancer, grade (G1, G2, G3), FIGO stage, nodal status, recurrence, menopausal status, parity, and body mass index. Statistical methods such as the chi-square test, analysis of variance and the Scheffé post-hoc test were used.

RESULTS

Two hundred and two patients with endometrioid endometrial cancer were included: 96 had blood group A, 19 blood group B, 75 blood group 0, and 12 had blood group AB. This distribution corresponds to the general blood group distribution in Germany. The vast majority of the dependent variables, such as grade, FIGO stage, nodal status or recurrence were not significantly associated with ABO blood group or Rhesus factor status. The relative frequencies of G1 and G3 endometrial cancers with respect to blood group were similar. Menopausal status, parity, and body mass index were not related to more advanced FIGO stages at initial diagnosis or to ABO blood group.

DISCUSSION

Blood group screening would probably not be helpful in the diagnosis of endometrioid endometrial carcinomas in early stages compared to the current gold standard. Furthermore, a specific blood group does not increase either the risk of recurrence or the risk of a dedifferentiated type of endometrial carcinoma.

Specific Combinations of Erythrocyte Group Antigens in Blood Donors

Blood groups are inherited biological characteristics that do not change throughout life only in healthy people. Blood group antigens determine the adaptation of a human, as a biological species, to the surrounding environment. Our goal was to study the combination and frequency characteristics of three group systems (ABO, RH, KELL) in blood donors. The blood of 743 donors (aged ≥ 18 years) has been investigated on erythrocyte blood group antigens (521 male and 222 female). The sample has been provided from diagnostic laboratory of "Health Centre Medina Ltd" of Batumi. Research was agreed with hematology department of the clinic. Blood typing of the sample has been carried out on the basis of immunogenetic laboratory of Batumi Shota Rustaveli State University. The express method with universal mono-clone antibodies was used in order to reveal blood group system antigens. ABO blood group are distributed the following order: O > A > B > AB. We allocated 16 phenotypic groups. O, Rh+, K- (38.62 ± 1.7%) are represented with the highest percentage among donors and a rather large number of the investigated donors (287 donors) is the carrier of this phenotype. A frequency distribution of the A, Rh+, K- phenotype group 10% (28.93 ± 1.6) was less. 215 donors carry A, Rh+, K- phenotype combination. O, Rh+, K+ and A, Rh+, K+ variations of the phenotype are represented with an equal percentage (3.23 ± 0.4%). 7.94 ± 0.9% donors are characterized by features of the O, Rh-, K- Erythrocyte group. A frequency distribution of B, Rh+, K- phenotype is slightly less - 6.86 ± 0.9%. A, Rh-, K combination of phenotype occurs with a frequency of 4.97 ± 0.7%, and AB, Rh+, K- occurs with a frequency of 2.28 ± 0.5%. I n the donor population there were only single cases of B, Rh-, K+ (0.13 ± 0.01); AB, Rh+, K+ (0.13 ± 0.01); AB, Rh-, K- (0.40 ± 0.2); B, Rh+, K+ (0.26 ± 0.1); O, Rh-, K+ (0.40 ± 0.2); A, Rh-, K+ (0.67 ± 0.2) combination of phenotype. The phenotype AB, Rh-, K+ was not identified. The existence of this database will increase the safety level of transfusion, widen donors database and allow the clinics to find quickly the rare combination of blood group for transfusion and decrease of the risk of post-transfusion complications.

Histo-Blood Group Antigens in Oral Cancer and Potentially Malignant Disorders

BACKGROUND

Early detection of oral cancer is of critical importance because survival rates markedly improve when oral lesions are identified at an early stage. Aim of the present study is to investigate the expression of ABO (H) antigens in tissue specimens of oral cancer and potentially malignant disorders and to determine the role of ABO (H) antigens in tumour staging.

MATERIALS AND METHODS

A prospective study was conducted on 60 cases of oral cancer and potentially malignant diseases. Specific red cell adherence test (SRCA-test) was used for studying A, B and O (H) antigens in tissue specimens and iso-antigenicity of epithelium was graded according to degree of adherence of indicator red blood cells.

RESULTS

Among OSMF group, grade II adherence was seen in 53.3% cases, grade III in 33.3% cases, grade IV in 13.3% cases. In leukoplakia group, grade II adherence was seen in 26.7% cases, grade III adherence in 53.3% cases, grade IV adherence in 20% cases. Within the leukoplakia group, cases with dysplasia showed decreased adherence, compared with cases without dysplasia. Oral cancer group, negative adherence was seen in 13.3% cases, grade I adherence in 46.7% cases, grade II in 40% cases. In oral cancer group, antigen reactivity was less in poorly and moderately differentiated carcinoma, compared to well differentiated carcinoma.

CONCLUSIONS

Antigen adherence and degree of loss of ABO (H) antigens in tissue specimens can be used for staging of the tumour.

ABO Blood Groups, Rh Factor, and Thyroid Cancer Risk: To 'B' or Not to 'B'

Purpose: In this study, we aimed to evaluate ABO blood groups and Rh factor in patients with thyroid cancer.Methods: Demographical and clinical features, cytological results, ABO blood groups, and Rh factor status of patients with benign and malignant thyroid disease were evaluated. Histopathological features of thyroid cancer were compared in Rh positive and negative patients, and patients with different ABO blood groups.Results: Histopathological diagnosis was benign in 1,299 (63.5%) and malignant in 744 (36.5%) patients. There was no significant difference between benign and malignant patients in terms of age, sex, thyroid autoantibody positivity, and ABO blood groups (p > .05 for each). A significantly higher rate of patients with malignant disease were Rh positive compared to patients with benign disease (91.8% vs. 88.1%, p = .046). In thyroid cancer patients, extrathyroidal extension and advanced stage (3-4) were observed more frequently in patients with B compared to non-B blood groups (p = .028 and 0.042, respectively). The likelihood of the extrathyroidal extension was 4.272 (95%: 1.816-10.049) times higher in B blood group compared to non-B blood groups in patients with multifocal disease (p < .001). Patients with O blood group had lower rate of capsular invasion than patients with non-O blood groups (p = .018).Conclusion: Patients with B blood group had higher risk of extrathyroidal extension and advanced stage compared to patients with non-B blood group.

Expression of Histo-blood Group Antigens in Tumor and Adjacent Normal Breast Tissues as Prognostic Markers of Breast Carcinoma

Purpose

Aberrant glycosylation of the histo-blood group antigens (including the angina bullosa haemorrhagica [ABH]) is often observed during malignant transformation in most types of carcinomas. Data concerning their ethnic distributions are diverse which explains why their biological characteristics have to be studied in different populations. Our aim was to analyze the expression of the histo-blood group (specifically the ABH) antigens in breast carcinoma.

Methods

The expression of the histo-blood group (specifically the ABH) antigens was studied in 109 patients with breast carcinoma using immunohistochemistry. Statistical analysis was performed using χ² and Fisher analyses.

Results

The loss of expression of histo-blood group (ABH) antigens in breast carcinoma was observed in 81.13% of patients with blood group O, 37.93% with blood group A, and 96.30% with blood group B. One key finding of this study was that the loss of expression of the ABH antigen was also observed in normal tissues adjacent to the tumor. The loss of expression was associated with higher tumor grade (p < 0.05). Expression of H antigen was observed in 50% of cases with loss of expression of B antigen and was associated with human epidermal growth factor receptor 2 (HER2) overexpression (p < 0.05). The loss of H antigen in patients with blood group O was associated with estrogen receptor expression (p < 0.001). Incompatible A antigen in tumor was expressed in 20.75% of patients with blood group O.

Conclusion

Loss of the ABH antigens correlated with the Scarff-Bloom-Richardson histologic grading. H antigen was associated with HER2 overexpression in breast cancer. However, further studies are needed to determine the role of incompatible A antigen in mammary carcinogenesis.

RUNX1 mutation in a patient with myelodysplastic syndrome and decreased erythrocyte expression of blood group A antigen

BACKGROUND

Loss of blood group ABO antigens on red blood cells (RBCs) is well known in patients with leukemias, and such decreased ABO expression has been reported to be strongly associated with hypermethylation of the ABO promoter. We investigated the underlying mechanism responsible for A-antigen reduction on RBCs in a patient with myelodysplastic syndrome.

STUDY DESIGN AND METHODS

Genetic analysis of ABO was performed by PCR and sequencing using peripheral blood. RT-PCR were carried out using cDNA prepared from total bone marrow (BM) cells. Bisulfite genomic sequencing was performed using genomic DNA from BM cells. Screening of somatic mutations was carried out using a targeted sequencing panel with genomic DNA from BM cells, followed by transient transfection assays.

RESULTS

Genetic analysis of ABO did not reveal any mutation in coding regions, splice sites, or regulatory regions. RT-PCR demonstrated reduction of A-transcripts when the patient's RBCs were not agglutinated by anti-A antibody and did not indicate any significant increase of alternative splicing products in the patient relative to the control. DNA methylation of the ABO promoter was not obvious in erythroid cells. Targeted sequencing identified somatic mutations in ASXL1, EZH2, RUNX1, and WT1. Experiments involving transient transfection into K562 cells showed that the expression of ABO was decreased by expression of the mutated RUNX1.

CONCLUSION

Because the RUNX1 mutation encoded an abnormally elongated protein without a transactivation domain which could act as dominant negative inhibitor, this frame-shift mutation in RUNX1 may be a genetic candidate contributing to A-antigen loss on RBCs.

The ABO Blood Group is an Independent Prognostic Factor in Patients with Ovarian Cancer

Previous studies have suggested a relationship between ABO blood group and clinical outcome of various cancers. Nevertheless, little is known about the association between ABO blood group and survival in patients with ovarian carcinoma. This study aimed to investigate the prognostic significance of ABO blood group in patients with ovarian carcinoma. 941 patients who were newly diagnosed with ovarian carcinoma between February 2007 and February 2016 were enrolled in the present study. The relationship between ABO blood type and clinical features in patients with ovarian cancer was analyzed using chi-square tests. Overall survival (OS) stratified by B antigen was evaluated using log-rank test and Kaplan-Meier method. Presence of the B antigen (B/AB) had a worse OS than those in the absence of the B antigen (A/O) in all patients with ovarian cancer, especially in patients with FIGO stage I, IV, and menopause. Presence of the B antigen (B/AB) was significantly correlated with OS than those with non-B antigen (A/O) (hazard ratios 1.342; 95% confidence interval 1.069-1.685; P=0.011). Multivariate analyses revealed that presence of the B antigen (B/AB) was independently associated with OS (hazard ratios 1.532; 95% confidence interval 1.111-2.112; P=0.009). This study indicated that presence of the B antigen (B/AB) was an unfavorable prognostic factor in ovarian carcinoma, especially in patients with FIGO stage I, IV, and menopause.

Genetic Variants of ABO and SOX6 are Associated With Adolescent Idiopathic Scoliosis in Chinese Han Population

STUDY DESIGN

A genetic association study.

OBJECTIVE

The aim of this study was to determine whether variants of ABO, SOX6, and CDH13 are associated with the susceptibility of AIS in Chinese Han population.

SUMMARY OF BACKGROUND DATA

A recent large-scale genome-wide association study reported three novel loci in CDH13, ABO, and SOX6 genes associated with adolescent idiopathic scoliosis (AIS) in Japanese population. However, the association of these three genes with AIS in other populations remains obscure.

METHODS

The SNPs rs4513093, rs687621, and rs1455114 were genotyped in 1208 female patients and 2498 healthy controls. Samples for the expression analysis in paraspinal muscles were collected from 49 AIS and 33 congenital scoliosis (CS) patients during surgical interventions. Chi-square analysis was used to assess the difference regarding genotype and allele frequency between cases and controls. Tissue expressions of ABO, CDH13, and SOX6 were compared between AIS and CS patients by the Student t test.

RESULTS

SNPs rs4513093 of CDH13 and rs687621 of ABO were found to be significantly associated with AIS with an odds ratio of 0.8691 and 1.203, respectively. There was no significant association of rs1455114 with AIS. Moreover, AIS patients were found to have significantly increased expression of ABO. As for expression of CDH13 and SOX6, no remarkable difference was found between the two groups.

CONCLUSION

The association of CDH13 and ABO variants with AIS was successfully replicated in the Chinese Han population. More studies are warranted to explore the functional role of ABO in the development of AIS.

LEVEL OF EVIDENCE

N/A.

Construction of prognostic risk prediction model of oral squamous cell carcinoma based on co-methylated genes

This study aimed to identify DNA methylation markers in oral squamous cell carcinoma (OSCC) and to construct a prognostic prediction model of OSCC. For this purpose, the methylation data of patients with OSCC downloaded from The Cancer Genome Atlas were considered as a training dataset. The methylation profiles of GSE37745 for OSCC samples were downloaded from Gene Expression Omnibus and considered as validation dataset. Differentially methylated genes (DMGs) were screened from the TCGA training dataset, followed by co-methylation analysis using weighted correlation network analysis (WGCNA). Subsequently, the methylation and gene expression levels of DMGs involved in key modules were extracted for correlation analysis. Prognosis-related methylated genes were screened using the univariate Cox regression analysis. Finally, the risk prediction model was constructed and validated through GSE52793. The results revealed that a total of 948 DMGs with CpGs were screened out. Co-methylation gene analysis obtained 2 (brown and turquoise) modules involving 380 DMGs. Correlation analysis revealed that the methylation levels of 132 genes negatively correlated with the gene expression levels. By combining with the clinical survival prognosis of samples, 5 optimized prognostic genes [centromere protein V (CENPV), Tubby bipartite transcription factor (TUB), synaptotagmin like 2 (SYTL2), occludin (OCLN) and CAS1 domain containing 1 (CASD1)] were selected for constructing a risk prediction model. It was consistent in the training dataset and GSE52793 that low-risk samples had a better survival prognosis. On the whole, this study indicates that the constructed risk prediction model based on CENPV, SYTL2, OCLN, CASD1, and TUB may have the potential to be used for predicting the survival prognosis of patients with OSCC.

AB0 Blood Group and Ovarian Cancer Survival

Background: Epithelial ovarian cancer is the most lethal gynecological malignancy because is usually diagnosed at advanced stage. New prognostic factors have been investigated but these biomarkers do not have a strong direct relationship with survival. Several studies investigated the association between AB0 blood group with ovarian cancer but with conflicting results. We investigated the association between AB0 blood group and epithelial ovarian cancer patients consecutively surgically treated at our department from 2004 to 2015.

Methods: Clinical charts of ovarian cancer patients treated and followed from 2004 to 2015 were checked for inclusion and exclusion criteria. Clinical and pathological data were recorded in an electronic separate, anonymous, password-protected database. All relevant data were extrapolated and used for final analysis.

Results: A population of 265 ovarian cancer patients was analyzed in this study. 121 (45.6%) patients presented blood type 0, 112 (42.3%) had blood type A, 23 (8.7%) B and 9 (3.4%) AB. A significantly lower percentage of death (8.7%) in patients with blood type B in comparison with patients presenting different genotypes (group 0: 34.7%, group A: 32.1%, group AB: 22.2%) was found. In invasive serous ovarian cancer patients the analysis showed a 5 fold significant reduction of the risk of death in patients with B genotype. However, postoperative residual tumor resulted the most important prognostic factor for overall survival.

Conclusions: AB0 blood group might be a preoperative prognostic factor in epithelial ovarian cancer patients. According to the literature, postoperative residual disease remain the most important prognostic factor also in our study.

ABO genotyping with next-generation sequencing to resolve heterogeneity in donors with serology discrepancies

BACKGROUND

ABO subtypes are characterized by the alteration of antigens present and their expression levels on red blood cells and many are linked to genetic changes in the ABO gene. Weakened expression of antigens should be identified to prevent transfusion reactions or ABO-incompatible transplantations. Genotyping can be applied to identify subtypes to complement serologic testing. Next-generation sequencing (NGS) has shown to provide sensitive and accurate genotyping results as well as valuable cis/trans information. Here we took advantage of NGS and applied it to resolve serology discrepancies in ABO typing.

STUDY DESIGN AND METHODS

In this study, we customized capture probes targeting the entire ABO gene and sequenced on MiSeq Illumina. The subtype-causing variants were identified, and cis/trans association to ABO alleles was determined. The results from NGS, serology, and Sanger sequencing were compared.

RESULTS

Four control samples typed A, B, O, and AB were correctly genotyped. Of 24 serologically discrepant samples, subtype-causing variations were found in 20 cases, with two unresolved and two identified as weakening of ABO antibody in reverse. The types of variations include 17 known subtype alleles, one novel variant, one novel large deletion, and one microchimerism. Haplotypes encompassing Exons 6 and 7 of ABO were reconstructed in 17 of the 20 samples.

CONCLUSION

This study demonstrated a full coverage of ABO by capture-based panel, phasing analysis with NGS in ABO genotyping resolved heterogeneity with novel allele and microchimerism findings. This approach provided a more precise method for subtyping and thereby leading to safer transfusion.

ABO blood groups as a prognostic factor for recurrence in ovarian and vulvar cancer

The relationship between ABO blood groups (BG) and risk of incidence in cancers including gynecological cancers has been widely studied, showing increased incidence risk for BG A patients. As available data are inconsistent we investigated whether BG and their anti-glycan antibodies (anti-A and anti-B) have prognostic values in gynecological cancers. We retrospectively evaluated 974 patients with gynecological cancers in three cancer centers (Switzerland and Australia) between 1974 and 2014 regarding the relationships between clinico-pathological findings and the BG. Time to disease recurrence was significantly influenced by BG in patients with ovarian (n = 282) and vulvar (n = 67) cancer. BG O or B patients showed a significantly increased risk for ovarian cancer relapse compared to A, 59% and 82%, respectively (p = 0.045; HR O vs A = 1.59 (CI 1.01-2.51) and (p = 0.036; HR A vs B = 0.55 (CI 0.32-0.96). Median time to relapse for advanced stage (n = 126) ovarian cancer patients was 18.2 months for BG O and 32.2 for A (p = 0.031; HR O vs A = 2.07 (CI 1.07-4.02)). BG also significantly influenced relapse-free survival in patients with vulvar cancer (p = 0.002), with BG O tending to have increased relapse risk compared to A (p = 0.089). Blood groups hence associate with recurrence in ovarian and vulvar cancer: women with BG O seem to have a lower ovarian cancer incidence, however are more likely to relapse earlier. The significance of the BG status as a prognostic value is evident and may be helpful to oncologists in prognosticating disease outcome and selecting the appropriate therapy.

Prognostic Impact of ABO Blood Group on Type I Endometrial Cancer Patients- Results from Our Own and Other Studies

Objectives: The ABO blood group antigens were found on most epithelial cells and in secretions. In the normal endometrium there is a variable expression of histo-blood group and related antigens suggesting a hormonal regulation. A relationship between ABO blood groups and endometrial cancer has been investigated with contradictory results. In this study we investigated the influence of blood types on clinical and pathological characteristics of endometrial cancer patients.

Method: Retrospective cohort study. Clinical and pathological data were extrapolated and their association with blood groups were assessed.

Results: A total of 203 type I endometrial cancer patients were included in the final analysis. Univariate analysis indicated that a lower frequency of G3 undifferentiated tumors was observed in patients with A blood group (P=0.027). Multivariate analysis, including also clinical features such as Age, BMI, parity, hypertension and diabetes confirmed that patients with A group present a lower risk of G3 tumors in comparison with not A patients. (OR=0.32, P=0.011).

Conclusions: Patients with A genotype have a lower risk to develop G3 type I endometrial cancer. ABO blood group might represent a useful, easy access and cheap biomarker for patients' selection and for management personalization of endometrial cancer patients.

Epigenetic Bases of Aberrant Glycosylation in Cancer

In this review, the sugar portions of glycoproteins, glycolipids, and glycosaminoglycans constitute the glycome, and the genes involved in their biosynthesis, degradation, transport and recognition are referred to as “glycogenes“. The extreme complexity of the glycome requires the regulatory layer to be provided by the epigenetic mechanisms. Almost all types of cancers present glycosylation aberrations, giving rise to phenotypic changes and to the expression of tumor markers. In this review, we discuss how cancer-associated alterations of promoter methylation, histone methylation/acetylation, and miRNAs determine glycomic changes associated with the malignant phenotype. Usually, increased promoter methylation and miRNA expression induce glycogene silencing. However, treatment with demethylating agents sometimes results in silencing, rather than in a reactivation of glycogenes, suggesting the involvement of distant methylation-dependent regulatory elements. From a therapeutic perspective aimed at the normalization of the malignant glycome, it appears that miRNA targeting of cancer-deranged glycogenes can be a more specific and promising approach than the use of drugs, which broad target methylation/acetylation. A very specific type of glycosylation, the addition of GlcNAc to serine or threonine (O-GlcNAc), is not only regulated by epigenetic mechanisms, but is an epigenetic modifier of histones and transcription factors. Thus, glycosylation is both under the control of epigenetic mechanisms and is an integral part of the epigenetic code.

ABO Blood-group Antigens in Oral Cancer

Tumor progression is often associated with altered glycosylation of the cell-surface proteins and lipids. The peripheral part of these cell-surface glycoconjugates often carries carbohydrate structures related to the ABO and Lewis blood-group antigens. The expression of histo-blood-group antigens in normal human tissues is dependent on the type of differentiation of the epithelium. In most human carcinomas, including oral carcinoma, a significant event is decreased expression of histo-blood-group antigens A and B. The mechanisms of aberrant expression of blood-group antigens are not clear in all cases. A relative down-regulation of the glycosyltransferase that is involved in the biosynthesis of A and B antigens is seen in oral carcinomas in association with tumor development. The events leading to loss of A transferase activity are related, in some instances, to loss of heterozygosity (LOH) involving chromosome 9q34, which is the locus for the ABO gene, and in other cases, to a hypermethylation of the ABO gene promoter. The fact that hypermethylation targets the ABO locus, but not surrounding genes, suggests that the hypermethylation is a specific tumor-related event. However, since not all situations with lack of expression of A/B antigens can be explained by LOH or hypermethylation, other regulatory factors outside the ABO promoter may be functional in transcriptional regulation of the ABO gene. Altered blood group antigens in malignant oral tissues may indicate increased cell migration. This hypothesis is supported by studies showing that normal migrating oral epithelial cells like malignant cells show lack of expression of A/B antigens, and by studies that target ABH antigens to key receptors controlling adhesion and motility, such as integrins, cadherins, and CD-44.

Epithelial Expression of Human ABO Blood Group Genes Is Dependent upon a Downstream Regulatory Element Functioning through an Epithelial Cell-specific Transcription Factor, Elf5

The human ABO blood group system is of great importance in blood transfusion and organ transplantation. The ABO system is composed of complex carbohydrate structures that are biosynthesized by A- and B-transferases encoded by the ABO gene. However, the mechanisms regulating ABO gene expression in epithelial cells remain obscure. On the basis of DNase I-hypersensitive sites in and around ABO in epithelial cells, we prepared reporter plasmid constructs including these sites. Subsequent luciferase assays and histone modifications indicated a novel positive regulatory element, designated the +22.6-kb site, downstream from ABO, and this was shown to enhance ABO promoter activity in an epithelial cell-specific manner. Expression of ABO and B-antigen was reduced in gastric cancer KATOIII cells by biallelic deletion of the +22.6-kb site using the CRISPR/Cas9 system. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that the site bound to an epithelial cell-specific transcription factor, Elf5. Mutation of the Ets binding motifs to abrogate binding of this factor reduced the regulatory activity of the +22.6-kb site. Furthermore, ELF5 knockdown with shRNA reduced both endogenous transcription from ABO and B-antigen expression in KATOIII cells. Thus, Elf5 appeared to be involved in the enhancer potential of the +22.6-kb site. These results support the contention that ABO expression is dependent upon a downstream positive regulatory element functioning through a tissue-restricted transcription factor, Elf5, in epithelial cells.

Glycoprotein B7-H3 overexpression and aberrant glycosylation in oral cancer and immune response

The incidence and mortality rate of oral cancer continue to rise, partly due to the lack of effective early diagnosis and increasing environmental exposure to cancer-causing agents. To identify new markers for oral cancer, we used a sialylation probe to investigate the glycoproteins differentially expressed on oral cancer cells. Of the glycoproteins identified, B7 Homolog 3 (B7-H3) was significantly overexpressed in oral squamous cell carcinoma (OSCC), and its overexpression correlated with larger tumor size, advanced clinical stage, and low survival rate in OSCC patients. In addition, knockdown of B7-H3 suppressed tumor cell proliferation, and restoration of B7-H3 expression enhanced tumor growth. It was also found that the N-glycans of B7-H3 from Ca9-22 oral cancer cells contain the terminal α-galactose and are more diverse with higher fucosylation and better interaction with DC-SIGN [DC-specific intercellular adhesion molecule-3 (ICAM-3)-grabbing nonintegrin] and Langerin on immune cells than that from normal cells, suggesting that the glycans on B7-H3 may also play an important role in the disease.

Prognostic role of the ABO blood types in Chinese patients with curatively resected non-small cell lung cancer: a retrospective analysis of 1601 cases at a single cancer center

Background

A positive association between the ABO blood types and survival has been suggested in several malignancies. The aim of this study was to assess the role of the ABO blood types in predicting the prognosis of Chinese patients with curatively resected non-small cell lung cancer (NSCLC).

Methods

We retrospectively analyzed 1601 consecutive Chinese patients who underwent curative surgery for NSCLC between January 1, 2005 and December 31, 2009. The relationship between the ABO blood types and survival was investigated. In addition, univariate and multivariate analyses were performed.

Results

Group 1 (patients with the blood type O or B) had significantly prolonged overall survival (OS) compared with group 2 (patients with the blood type A or AB), with a median OS of 74.9 months versus 61.5 months [hazard ratio (HR) 0.83; 95% confidence interval (CI) 0.72–0.96; P = 0.015]. Additionally, group 1 had significantly longer disease-free survival (DFS; HR 0.86; 95% CI 0.76–0.98; P = 0.022) and locoregional relapse-free survival (LRFS; HR 0.79; 95% CI 0.64–0.98; P = 0.024) than group 2. The association was not significantly modified by other risk factors for NSCLC, including smoking status, pathologic tumor-node-metastasis stage, pT category, pN category, and chemotherapy.

Conclusions

There is an association between the ABO blood types and the survival of Chinese patients with resected NSCLC. Patients with the blood type O or B had significantly prolonged OS, DFS, and LRFS compared with those with the blood type A or AB.

Blood Groups in Infection and Host Susceptibility

Blood group antigens represent polymorphic traits inherited among individuals and populations. At present, there are 34 recognized human blood groups and hundreds of individual blood group antigens and alleles. Differences in blood group antigen expression can increase or decrease host susceptibility to many infections. Blood groups can play a direct role in infection by serving as receptors and/or coreceptors for microorganisms, parasites, and viruses. In addition, many blood group antigens facilitate intracellular uptake, signal transduction, or adhesion through the organization of membrane microdomains. Several blood groups can modify the innate immune response to infection. Several distinct phenotypes associated with increased host resistance to malaria are overrepresented in populations living in areas where malaria is endemic, as a result of evolutionary pressures. Microorganisms can also stimulate antibodies against blood group antigens, including ABO, T, and Kell. Finally, there is a symbiotic relationship between blood group expression and maturation of the gastrointestinal microbiome.

ABO blood group, Epstein-Barr virus infection and prognosis of patients with non-metastatic nasopharyngeal carcinoma

BACKGROUND

A prior study showed blood type A/AB to be associated with an increased risk of nasopharyngeal carcinoma (NPC) compared to subjects with blood type O. However, the relationship between ABO blood groups and prognosis of NPC patients is still questionable. In addition, whether Epstein-Barr virus (EBV) infection is associated with prognosis of NPC patients with different ABO blood groups is unclear.

MATERIALS AND METHODS

We conducted univariate and multivariable Cox regression analyses based on a consecutive cohort of 1,601 patients to investigate the above issues.

RESULTS

There was no significant difference in overall survival (OS) between different ABO blood groups (p=0.629), neither between A vs. non-A blood groups (p=0.895) nor AB vs. non-AB blood group (p=0.309) in univariate analyses and after adjusting for other factors. Interaction tests revealed that high immunoglobulin A against Epstein-Barr virus viral capsid antigen (VcA-IgA) level was associated with a favorable prognosis in male patients with UICC stage II disease who had an A blood type (p=0.008), compared with those with non-A blood type. In addition, male patients with an A blood group with a high blood lymphocyte level showed a tendency towards better survival in UICC stage III (p=0.096).

CONCLUSIONS

ABO blood group status is not associated with the prognosis of patients with NPC. Additionally, blood group A male NPC patients with high VcA-IgA level or high blood lymphocyte counts might be correlated with a favorable prognosis in UICC stage II or III, respectively.

Epigenetic regulation of protein glycosylation

Protein N-glycosylation is an ancient metabolic pathway that still exists in all three domains of life (Archaea, Bacteria and Eukarya). The covalent addition of one or more complex oligosaccharides (glycans) to protein backbones greatly diversifies their structures and makes the glycoproteome several orders of magnitude more complex than the proteome itself. Contrary to polypeptides, which are defined by a sequence of nucleotides in the corresponding genes, the glycan part of glycoproteins are encoded in a complex dynamic network of hundreds of proteins, whereby activity is defined by both genetic sequence and the regulation of gene expression. Owing to the complex nature of their biosynthesis, glycans are particularly versatile and apparently a large part of human variation derives from differences in protein glycosylation. Composition of the individual glycome appears to be rather stable, and thus differences in the pattern of glycan synthesis between individuals could originate either from genetic polymorphisms or from stable epigenetic regulation of gene expression in different individuals. Studies of epigenetic modification of genes involved in protein glycosylation are still scarce, but their results indicate that this process might be very important for the regulation of protein glycosylation.

Sevoflurane attenuate hypoxia-induced VEGF level in tongue squamous cell carcinoma cell by upregulating the DNA methylation states of the promoter region

Anaesthetic agents were confirmed to play a role on the tumor angiogenesis. The effect of sevoflurane on tongue squamous cell carcinoma (TSCC) cell has not been investigated. SCC-4 cells were exposed to sevoflurane after simulating hypoxia. Then, both the mRNA and protein level of hypoxia-inducible factor (HIF)-1α and VEGF were detected. The methylation states of the VEGF promoter region were also assessed to reveal the underlying mechanism. Finally, the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-Aza) was administrated to reveal the relationship of DNA methylation on the regulation of the VEGF level. Results showed that sevoflurane attenuated the hypoxia-induced VEGF level without altering the HIF-1α after exposure for 24 and 72 h. Sevoflurane increased the DNA methylation of the VEGF promoter region. The attenuation effect of sevoflurane on hypoxia-induced VEGF level could be blocked by 5-Aza. We concluded that sevoflurane attenuates hypoxia-induced VEGF level via DNA methylation of the promoter region in TSCC cell.

Quantitative methodology is critical for assessing DNA methylation and impacts on correlation with patient outcome

BACKGROUND

DNA hypermethylation is reported as a frequent event and prognostic marker in head and neck squamous cell carcinomas (HNSCC). Methylation has been commonly assessed with non-quantitative methodologies, such as methylation-specific PCR (MSP). We investigated previously reported hypermethylated genes with quantitative methodology in oral tongue squamous cell carcinomas (OTSCC).

RESULTS

The methylation status of 12 genes in 115 OTSCC samples was assessed by one or more of three quantitative analyses: methylation sensitive high resolution melting (MS-HRM), sensitive-melting analysis after real time-methylation specific PCR (SMART-MSP), and bisulfite pyrosequencing. In contrast to much of the literature, either no or infrequent locus-specific methylation was identified by MS-HRM for DAPK1, RASSF1A, MGMT, MLH1, APC, CDH1, CDH13, BRCA1, ERCC1, and ATM. The most frequently methylated loci were RUNX3 (18/108 methylated) and ABO (22/107 methylated). Interrogation of the Cancer Genome Atlas (TCGA) HNSCC cohort confirmed the frequency of significant methylation for the loci investigated. Heterogeneous methylation of RUNX3 (18/108) and ABO (22/107) detected by MS-HRM, conferred significantly worse survival (P = 0.01, and P = 0.03). However, following quantification of methylation levels using pyrosequencing, only four tumors had significant quantities (>15%) of RUNX3 methylation which correlated with a worse patient outcome (P <0.001), while the prognostic significance of ABO hypermethylation was lost. RUNX3 methylation was not prognostic for the TCGA cohort (P = 0.76).

CONCLUSIONS

We demonstrated the critical need for quantification of methylation levels and its impact on correlative analyses. In OTSCC, we found little evidence of significant or frequent hypermethylation of many loci reported to be commonly methylated. It is likely that previous reports have overestimated the frequency of significant methylation events as a consequence of the use of non-quantitative methodology.

Control of Glycosylation-Related Genes by DNA Methylation: the Intriguing Case of the B3GALT5 Gene and Its Distinct Promoters

Glycosylation is a metabolic pathway consisting of the enzymatic modification of proteins and lipids through the stepwise addition of sugars that gives rise to glycoconjugates. To determine the full complement of glycoconjugates that cells produce (the glycome), a variety of genes are involved, many of which are regulated by DNA methylation. The aim of the present review is to briefly describe some relevant examples of glycosylation-related genes whose DNA methylation has been implicated in their regulation and to focus on the intriguing case of a glycosyltransferase gene (B3GALT5). Aberrant promoter methylation is frequently at the basis of their modulation in cancer, but in the case of B3GALT5, at least two promoters are involved in regulation, and a complex interplay is reported to occur between transcription factors, chromatin remodelling and DNA methylation of typical CpG islands or even of other CpG dinucleotides. Transcription of the B3GALT5 gene underwent a particular evolutionary fate, so that promoter hypermethylation, acting on one transcript, and hypomethylation of other sequences, acting on the other, cooperate on one gene to obtain full cancer-associated silencing. The findings may also help in unravelling the complex origin of serum CA19.9 antigen circulating in some patients.

Impact of ABO blood type on outcomes in patients with primary nonmuscle invasive bladder cancer

PURPOSE

ABO blood type is an established prognostic factor for several malignancies but its role in bladder urothelial carcinoma is largely unknown. We determined whether ABO blood type is associated with the outcome of transurethral resection of nonmuscle invasive bladder urothelial carcinoma.

MATERIALS AND METHODS

We retrospectively studied ABO blood types in 931 patients with primary nonmuscle invasive bladder urothelial carcinoma treated with transurethral bladder resection with or without intravesical instillation therapy. Disease recurrence and progression were analyzed with univariable and multivariable competing risks regression models. Median followup was 67 months. Discrimination was evaluated by the concordance index.

RESULTS

The ABO blood type was O, A, B and AB in 414 (44.5%), 360 (38.7%), 103 (11.1%) and 54 patients (5.8%), respectively. ABO blood type was significantly associated with outcome on univariable and multivariable analysis. Overall, patients with blood type O had worse recurrence and progression rates than those with A (p = 0.015 and 0.031) or B (p = 0.004 and 0.075, respectively). The concordance index of multivariable base models increased after including ABO blood type.

CONCLUSIONS

In patients with nonmuscle invasive bladder urothelial carcinoma the ABO blood type may predict the outcome. Those with blood type O showed the highest recurrence and progression rates. Including ABO blood type in multivariable models increases the accuracy of standard prognostic factors. Since the ABO blood type is available for most patients, it may represent an ideal adjunctive marker to predict recurrence and progression. The biological explanation and prognostic value of this finding must be further elucidated.

ABO blood group and nasopharyngeal carcinoma risk in a population of Southeast China

Previous studies found that the ABO blood type alters the individual susceptibility of some malignancies. However, whether such an association exists between ABO blood type and nasopharyngeal carcinoma (NPC) remains unknown. A case-control study was conducted, with 1,538 patients who had NPC and 1,260 cancer-free controls. The association between ABO blood type and NPC incidence was evaluated using unconditional logistic regression analysis. Compared with subjects with blood type O, a relatively higher risk was observed among cases with blood types A or AB, with ORs (95% confidence interval) of 1.287 (1.072 - 1.545), p = 0.007 and 1.390 (1.007 - 1.919), p = 0.045, respectively, after adjusting for gender, age, smoking status and family history of cancer. The rate of distant metastasis was significantly higher among male patients with blood type A than in patients with non-A blood types (6.8 vs. 3.5%, p = 0.027). Our results suggest that blood types A or AB is associated with an increased risk of NPC. Further studies are needed to confirm this association and to explore the mechanisms involved.

MicroRNA-137 promoter methylation in oral lichen planus and oral squamous cell carcinoma

Oral lichen planus (OLP) is a common oral mucosal disease, which is generally considered a potentially malignant lesion. To identify efficiently prognostic biomarker, we investigated the microRNA-137 (miR-137) promoter methylation in OLP and compared with the samples from healthy volunteers and patients with oral squamous cell carcinoma (OSCC). A total of 20 OLP and 12 patients with OSCC as well as 10 healthy subjects were subjected to miR-137 promoter methylation analysis using methylation-specific PCR (MSP). To address the malignancy prediction potential from miR-137 promoter methylation status, methylation of the p16 gene, a well-known tumor suppressor, was investigated in the same samples. The p16 methylation and miR-137 promoter methylation were found to be 25% and 35% in patients with OLP, 50% and 58.3% in patients with OSCC, and 0% and 0% in healthy subjects, respectively. The differences between miR-137 and p16 methylation levels were statistically significant between healthy controls and patients. Methylation levels of the two promoters were also influenced by age, gender, and lesion duration. Interestingly, aberrant promoter methylation of the p16 and miR-137 genes was only found in the epithelium but not in the connective tissue from patients with OLP. This raises the possibility to use miR-137 methylation as a biomarker for malignant prediction in patients with OLP.

Epigenetic silencing of the chaperone Cosmc in human leukocytes expressing tn antigen

Cosmc is the specific molecular chaperone in the endoplasmic reticulum for T-synthase, a Golgi β3-galactosyltransferase that generates the core 1 O-glycan, Galβ1-3GalNAcα-Ser/Thr, in glycoproteins. Dysfunctional Cosmc results in the formation of inactive T-synthase and consequent expression of the Tn antigen (GalNAcα1-Ser/Thr), which is associated with several human diseases. However, the molecular regulation of expression of Cosmc, which is encoded by a single gene on Xq24, is poorly understood. Here we show that epigenetic silencing of Cosmc through hypermethylation of its promoter leads to loss of Cosmc transcripts in Tn4 cells, an immortalized B cell line from a male patient with a Tn-syndrome-like phenotype. These cells lack T-synthase activity and express the Tn antigen. Treatment of cells with 5-aza-2'-deoxycytidine causes restoration of Cosmc transcripts, restores T-synthase activity, and reduces Tn antigen expression. Bisulfite sequencing shows that CG dinucleotides in the Cosmc core promoter are hypermethylated. Interestingly, several other X-linked genes associated with glycosylation are not silenced in Tn4 cells, and we observed no correlation of a particular DNA methyltransferase to aberrant methylation of Cosmc in these cells. Thus, hypermethylation of the Cosmc promoter in Tn4 cells is relatively specific. Epigenetic silencing of Cosmc provides another mechanism underlying the abnormal expression of the Tn antigen, which may be important in understanding aberrant Tn antigen expression in human diseases, including IgA nephropathy and cancer.

ABO blood group is a predictor of survival in patients undergoing surgery for renal cell carcinoma

What's known on the subject? and What does the study add? Some evidence suggests that ABO blood type may be a risk factor for cancer incidence and prognosis. For example, a large study recently discovered an increased incidence of pancreatic cancer in patients with non-O blood type; however, it is not known whether blood group correlates with outcomes in patients with RCC. We found a significant and independent association between ABO blood group and overall survival in patients undergoing surgery for locoregional RCC. Specifically, we identified non-O blood type as a predictor of mortality.

OBJECTIVE

• To determine whether ABO blood group is associated with survival after nephrectomy or partial nephrectomy for renal cell carcinoma (RCC).

PATIENTS AND METHODS

• We conducted a retrospective cohort study of 900 patients who underwent surgery for locoregional RCC between 1997 and 2008 at a single institution. • Covariates included age, gender, race, American Society of Anesthesiology Physical Status, preoperative anaemia and hypoalbuminemia, tumour characteristics, lymph node status, procedure performed, transfusion status and ABO blood group. • Primary outcomes were overall (OS) and disease-specific survival (DSS). • Univariable survival analyses were performed using the Kaplan-Meier and log-rank methods. Multivariable analysis was performed using a Cox proportional hazards model.

RESULTS

• The 3-year OS estimate was 75% (95%CI 70-79%) for O blood group and 68% (95% CI 63-73%) for non-O blood group (P= 0.072). The 3-year DSS was 81% (95% CI 76-85%) for O blood group and 76% (95%CI 71-80%) for non-O blood group (P= 0.053). • In the multivariable analysis for OS, non-O blood type was significantly associated with decreased OS (HR 1.68, 95%CI 1.18-2.39; P= 0.004) but not DSS (HR 1.53, 95%CI 0.97-2.41; P= 0.065).

CONCLUSION

• These data suggest that ABO blood group is independently associated with OS in patients undergoing surgery for locoregional RCC. ABO blood group has not been previously recognized as a predictor of survival in RCC.

Expression of the gene encoding secretor type galactoside 2 α fucosyltransferase (FUT2) and ABH antigens in patients with oral lesions

OBJECTIVE

The aim of this work was to evaluate the expression of FUT2 gene in saliva and histo ABH antigens of patients with oral lesions.

STUDY DESIGN

In total 178 subjects were examined, half of whom suffered from oral pre-cancerous and cancerous lesions, while the other half were the healthy control group We analyzed the FUT 2 polymorphism by ASO-PCR (allele specific oligonucleotid - polymerase chain reaction) with specific primers for G428 allele and the wild type allele of FUT2 gene. To reveal A, B and H antigens in tissue sections of the patients (n= 89) we used a modified specific red cell adherence technique.

RESULTS

We found a high intensity of oral disease in the non-secretor group (OR = 2.43). A total of 58% of the patients with oral pre-cancerous and cancerous lesions was non secretors (se_/_), in contrast with the healthy population (21.5%). A strongly positive reaction was defined as a sheet of indicator erythrocytes adhered to the epithelial cells. In 31 of the 54 samples analyzed the test showed slightly positive results on atypical areas, and there was a complete antigen deletion in areas affected by neoplasia. Nineteen samples showed a total absence of ABH antigens in both histologically normal and pathological areas. Blood group antigens were expressed at a high level in benign and highly differentiated malignant tumors. In poorly differentiated malignant tumors, they were mostly absent.

CONCLUSION

Considering these results we suggest the use of this method to monitor probable preneoplastic lesions in risk population, especially in those with no secretor status (absence of FUT2 gene).

Epigenome and DNA methylation in oral squamous cell carcinoma

Epigenetics studies and defines inherited changes in gene expression that are not encoded in the DNA sequence. The most studied epigenetic change in mammalian DNA is cytosine methylation in CpG dinucleotide areas. The other main group in epigenetic changes includes the posttranslational modifications of histones, mainly phosphorylation, deacetylation changes, and in the ubiquitinylation status. Oral squamous cell carcinoma is the most common malignancy of the oral cavity, and epigenetic changes are very common, as described in this chapter. Alterations in the DNA methylation status resulting from exposure to environmental stress agents have been documented even before birth. Although many epigenetic markers are potentially reversible, the mechanism still remains unclear and many epigenetic changes persist across cell lines and the life of the organism.

Current trends in miRNAs and their relationship with oral squamous cell carcinoma

A micro RNA (miRNA) is a single-stranded endogenous, non-coding RNA, with length ranging between 18 and 24 nucleotides and the ability of regulating the expression of other genes on a post-transcriptional level by means of various processes, degradation or repression of target mRNA. miRNAs play a crucial role in regulating fundamental processes such as cell cycle, differentiation and apoptosis; thus, their deregulation can affect normal cell growth and development, and even participate in carcinogenesis. The goals of this paper are: to outline the formation and functions of miRNAs; to determine their role in oral squamous cell carcinoma; to analyze the different miRNAs described and their roles as oncogenes or tumor suppressor genes, depending on their overexpression or subexpression; to describe the different polymorphisms and epigenetic alterations identified; and to determine their role in multidrug resistance.

Prognostic influence of loss of blood group A antigen expression in pathologic stage I non-small-cell lung cancer

INTRODUCTION

In the scientific literature, contradictory results has been published on the prognostic value of the loss of expression of blood group antigen A (BAA) in lung cancer. The objective of our study was to analyze this fact in our surgical series.

PATIENTS AND METHODS

In a multicenter study, 402 non-small-cell lung cancer (NSCLC) patients were included. All were classified as stage-I according to the last 2009-TNM classification. We analyzed the prognostic influence of the loss of expression of BAA in the 209 patients expressing blood group A or AB.

RESULTS

The 5-year cumulative survival was 73% for patients expressing BAA vs 53% for patients with loss of expression (P=.03). When patients were grouped into stages IA and IB, statistical significance was only observed in stage I-A (P=.038). When we analyzed the survival according to histologic type, those patients with adenocarcinoma and loss of expression of BAA had a lower survival rate that was statistically very significant (P=.003). The multivariate analysis showed that age, gender and expression of BAA were independent prognostic factors.

CONCLUSIONS

The loss of expression of blood group antigen A has a negative prognostic impact in stage I NSCLC, especially in patients with adenocarcinoma.

MicroRNA alterations and associated aberrant DNA methylation patterns across multiple sample types in oral squamous cell carcinoma

Background

MicroRNA (miRNA) expression is broadly altered in cancer, but few studies have investigated miRNA deregulation in oral squamous cell carcinoma (OSCC). Epigenetic mechanisms are involved in the regulation of >30 miRNA genes in a range of tissues, and we aimed to investigate this further in OSCC.

Methods

TaqMan® qRT-PCR arrays and individual assays were used to profile miRNA expression in a panel of 25 tumors with matched adjacent tissues from patients with OSCC, and 8 control paired oral stroma and epithelium from healthy volunteers. Associated DNA methylation changes of candidate epigenetically deregulated miRNA genes were measured in the same samples using the MassArray® mass spectrometry platform. MiRNA expression and DNA methylation changes were also investigated in FACS sorted CD44^high oral cancer stem cells from primary tumor samples (CSCs), and in oral rinse and saliva from 15 OSCC patients and 7 healthy volunteers.

Results

MiRNA expression patterns were consistent in healthy oral epithelium and stroma, but broadly altered in both tumor and adjacent tissue from OSCC patients. MiR-375 is repressed and miR-127 activated in OSCC, and we confirm previous reports of miR-137 hypermethylation in oral cancer. The miR-200 s/miR-205 were epigenetically activated in tumors vs normal tissues, but repressed in the absence of DNA hypermethylation specifically in CD44^high oral CSCs. Aberrant miR-375 and miR-200a expression and miR-200c-141 methylation could be detected in and distinguish OSCC patient oral rinse and saliva from healthy volunteers, suggesting a potential clinical application for OSCC specific miRNA signatures in oral fluids.

Conclusions

MiRNA expression and DNA methylation changes are a common event in OSCC, and we suggest miR-375, miR-127, miR-137, the miR-200 family and miR-205 as promising candidates for future investigations. Although overall activated in OSCC, miR-200/miR-205 suppression in oral CSCs indicate that cell specific silencing of these miRNAs may drive tumor expansion and progression.

DNA hypermethylation as an epigenetic mark for oral cancer diagnosis

Oral cancer is the largest group of cancers which fall into the head and neck category. While genetic alterations in oral cancer have long been documented, the effect of epigenetic changes is more recent. The recent explosion in science of how chromatin organization modulates the gene expression has highlighted the epigenetic mechanism of oral cancer pathogenesis. DNA methylation, which is an important epigenetic marker, is perhaps the best characterized chemical modification of mammalian DNA and provides a stable, heritable, and critical component of epigenetic regulation. This review attempts to decipher the epigenetic aspects of oral cancer by evaluating the DNA methylation status through its various stages from normal to potentially malignant to malignant states. In doing so, we emphasize DNA methylation as a novel biomarker in oral cancer research, thus opening newer avenues in oral cancer research.

DMBA-induced hamster buccal pouch carcinoma and VX2-induced rabbit cancer as a model for human oral carcinogenesis

In this article, we have described and compared the advantages and disadvantages of two potential animal cancer models (the hamster buccal pouch cancer model and the VX2-induced rabbit cancer model) for human squamous cell carcinomas of the oral mucosa. Currently, no animal cancer model is perfectly applicable to human oral squamous cell carcinomas. This is because the hamster buccal pouch cancer model has a different etiology and genetic constitution compared with human oral carcinomas. In addition, the VX2-induced rabbit cancer model is not produced in situ and, consequently, its natural behavior is totally reliant on the location of transplantation. Nonetheless, with the use of these two animal cancer models together, researchers could evaluate different aspects of the cellular and molecular biological characteristics or assess potential novel treatment regimens for squamous cell carcinomas of the human oral mucosa.