Long-term Outcomes of Tetralogy of Fallot in the Kingdom of Bahrain.

Introduction: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Surgical correction has improved survival but re-intervention is often required. Objectives: The objective is to assess outcomes after surgical repair of TOF, long-term follow-up, and factors that influence these results. Materials and Methods: This is a retrospective study conducted in a tertiary care center. Records of patients diagnosed with TOF from 1992 to 2019 (37 years) were retrieved from a detailed database. Patients who underwent complete correction were grouped according to diagnosis, the technique utilized in surgical repair, need for staged repair, and syndromic association. Univariate actuarial and event-free survival analysis was performed. The endpoint for an event was death or re-intervention. Results: A total of 230 patients were diagnosed with TOF and 174 patients underwent complete surgical repair. At 40 years postoperatively, survival was 96%. Actuarial survival was independent of syndromic associations, anatomical diagnosis, type of surgery, or previous shunt. Event-free survival (EFS) survival was 8.12%. EFS was significantly worse for patients with pulmonary atresia (PA) (Hazard ratio, 4.1125; 95% confidence interval [CI], 1.2654-13.3657; P < 0.0001) and for those that required homograft/conduit. The median duration for EFS was 22.73 years, 19.58 years, and 9.12 years for transannular patch (TAP), pulmonary valve-sparing (PVS), and homograft group, respectively. The survival curve for the PVS group merged with that of TAP 20 years postoperatively. Similarly, it merged at 22 years for staged versus primary repair and at 22.73 years for syndromic versus nonsyndromic patients. A weak correlation was found between age at surgery and event-free duration (cc, 0.309; P < 0.0001). The need for TAP was not influenced by the previous palliation, χ2(1, n = 154) = 3.36, P = 0.0667, or with interval to complete correction after the shunt procedure (P = 0.9672). Conclusions: Total correction of TOF has low perioperative mortality and good long-term survival, but the need for re-interventions is high. This study demonstrated that patients requiring homograft/conduit and those with a diagnosis of PA had worse outcomes. Comparison between different surgical groups showed merging of survival curves in follow-up that signifies gradual loss of survival advantage over time.

Clinical Identification of Dysregulated Circulating microRNAs and Their Implication in Drug Response in Triple Negative Breast Cancer (TNBC) by Target Gene Network and Meta-Analysis.

Resistance to therapy is a persistent problem that leads to mortality in breast cancer, particularly triple-negative breast cancer (TNBC). MiRNAs have become a focus of investigation as tissue-specific regulators of gene networks related to drug resistance. Circulating miRNAs are readily accessible non-invasive potential biomarkers for TNBC diagnosis, prognosis, and drug-response. Our aim was to use systems biology, meta-analysis, and network approaches to delineate the drug resistance pathways and clinical outcomes associated with circulating miRNAs in TNBC patients. MiRNA expression analysis was used to investigate differentially regulated circulating miRNAs in TNBC patients, and integrated pathway regulation, gene ontology, and pharmacogenomic network analyses were used to identify target genes, miRNAs, and drug interaction networks. Herein, we identified significant differentially expressed circulating miRNAs in TNBC patients (miR-19a/b-3p, miR-25-3p, miR-22-3p, miR-210-3p, miR-93-5p, and miR-199a-3p) that regulate several molecular pathways (PAM (PI3K/Akt/mTOR), HIF-1, TNF, FoxO, Wnt, and JAK/STAT, PD-1/PD-L1 pathways and EGFR tyrosine kinase inhibitor resistance (TKIs)) involved in drug resistance. Through meta-analysis, we demonstrated an association of upregulated miR-93, miR-210, miR-19a, and miR-19b with poor overall survival outcomes in TNBC patients. These results identify miRNA-regulated mechanisms of drug resistance and potential targets for combination with chemotherapy to overcome drug resistance in TNBC. We demonstrate that integrated analysis of multi-dimensional data can unravel mechanisms of drug-resistance related to circulating miRNAs, particularly in TNBC. These circulating miRNAs may be useful as markers of drug response and resistance in the guidance of personalized medicine for TNBC.

Partial anomalous pulmonary venous connection with accessory pulmonary veins.

We present a case of a six-year-old boy with complex partial anomalous pulmonary venous connections with accessory pulmonary veins, where multi-detector computed tomography proved crucial for accurate identification prior to planning for surgical correction.

Robust expression of tumor suppressor miRNA's let-7 and miR-195 detected in plasma of Saudi female breast cancer patients.

BACKGROUND: Female breast cancer is frequently diagnosed at a later stage and the leading cause of cancer deaths world-wide. Levels of cell-free circulating microRNAs (miRNAs) can potentially be used as biomarkers to measure disease progression in breast cancer patients in a non-invasive way and are therefore of high clinical value. METHODS: Using quantitative RT-PCR, circulating miRNAs were measured in blood samples collected from disease-free individuals (n = 34), triple-negative breast tumours (TNBC) (n = 36) and luminal tumours (n = 57). In addition to intergroup comparisons, plasma miRNA expression levels of all groups were analyzed against RNASeq data from cancerous breast tissue via The Cancer Genome Atlas (TCGA). RESULTS: A differential set of 18 miRNAs were identified in the plasma of breast cancer patients and 10 miRNAs were uniquely identified based on ROC analysis. The most striking findings revealed elevated tumor suppressor let-7 miRNA in luminal breast cancer patients, irrespective of subtype, and elevated miR-195 in plasma of TNBC breast cancer patients. In contrast, hsa-miR-195 and let-7 miRNAs were absent from cancerous TCGA tissue and strongly expressed in surrounding non-tumor tissue indicating that cancerous cells may selectively export tumor suppressor hsa-miR-195 and let-7 miRNAs in order to maintain oncogenesis. CONCLUSIONS: While studies have indicated that the restoration of let-7 and miR-195 may be a potential therapy for cancer, these results suggested that tumor cells may selectively export hsa-miR-195 and let-7 miRNAs thereby neutralizing their potential therapeutic effect. However, in order to facilitate earlier detection of breast cancer, blood based screening of hsa-miR-195 and let-7 may be beneficial in a female patient cohort.

Development and pre-clinical evaluation of new 68Ga-NOTA-folate conjugates for PET imaging of folate receptor-positive tumors.

In an attempt to develop new folate radiotracers with favorable biochemical properties for detecting folate receptor-positive cancers, we synthesized 68Ga-NOTA- and 68Ga-NOTAM-folate conjugates using a straightforward and a one-step simple reaction. Radiochemical yields were greater than 95% (decay-corrected) with total synthesis time of less than 20 min. Radiochemical purities were always greater than 98% without high-performance liquid chromatography (HPLC) purification. These synthetic approaches hold considerable promise as a rapid and simple method for 68Ga-folate conjugate preparation with high radiochemical yield in a short synthesis time. In vitro tests on the KB cell line showed that significant amounts of the radioconjugates were associated with cell fractions. Biodistribution studies in nude mice bearing human KB xenografts, demonstrated a significant tumor uptake and favorable biodistribution profile for 68Ga-NOTA-folate over the 68Ga-NOTAM-folate conjugate. The uptake in the tumors was blocked by excess injection of folic acid, suggesting a receptor-mediated process. These results demonstrate that the 68Ga-NOTA-folate conjugate may be useful as a molecular probe for detection and staging of folate receptor-positive cancers, such as ovarian cancer and their metastasis, as well as monitoring tumor response to treatment.

The molecular significance of methylated BRCA1 promoter in white blood cells of cancer-free females.

BACKGROUND: BRCA1 promoter methylation has been detected in DNA from peripheral blood cells of both breast cancer patients and cancer-free females. However, the pathological significance of this epigenetic change in white blood cells (WBC) remains an open question. In this study, we hypothesized that if constitutional BRCA1 methylation reflects an elevated risk for developing breast cancer (BC), WBC that harbor methylated BRCA1 in both cancer-free females and BC patients should exhibit similar molecular changes. METHODS: BRCA1 promoter methylation was examined by methylation-specific PCR in WBC from 155 breast cancer patients and 143 cancer-free females. The Human Breast Cancer EpiTect Methyl II Signature PCR Array and The Human Breast Cancer RT2 Profiler™ PCR Array were used to study the methylation status and the expression profile of several breast cancer-related genes, respectively. In addition, we used label-free MS-based technique to study protein expression in plasma. RESULTS: We have shown that 14.2% of BC patients and 9.1% of cancer-free females (carriers) harbored methylated BRCA1 promoter in their WBC. Interestingly, 66.7% of patients harbored methylated BRCA1 promoter in both WBC and tumors. Importantly, we have shown the presence of epigenetic changes in 9 other BC-related genes in WBC of both patients and carriers. Additionally, BRCA1 and 15 other important cancer -related genes were found to be differentially expressed in WBC from patients and carriers as compared to controls. Furthermore, we have shown that the carriers exhibited a unique plasma protein pattern different from those of BC patients and controls, with 10 proteins similarly differentially expressed in patients and carriers as compared to controls. CONCLUSIONS: The present results suggest the presence of a strong link between aberrant methylation of the BRCA1 promoter in WBC and breast cancer -related molecular changes, which indicate the potential predisposition of the carriers for developing breast cancer. This informs the potential use of the aberrant methylation of BRCA1 promoter in WBC as a powerful non-invasive molecular marker for detecting predisposed individuals at a very early age.

Obesity is a significant risk factor for breast cancer in Arab women.

BACKGROUND: Breast cancer (BC) is the most common malignancy and the leading cause of cancer-related death amongst women worldwide. The risk factors of this disease are numerous, and their prevalence varies between racial and ethnic groups as well as geographical regions. Therefore, we sought to delineate the association of socio-demographic, reproductive and life-style related risk factors with breast cancer in the Arab population. METHODS: Unmatched case-control study was conducted in the kingdom of Saudi Arabia using 534 cases of histologically confirmed breast cancer and 638 controls. Controls were randomly selected from primary health care visits and were free of breast cancer. Unconditional logistic regression analysis was performed to estimate odds ratios (ORs) and to examine the predictive effect of each factor on risk for BC. All study participants were interviewed by trained interviewers at hospital (cases) or at primary health care centers (controls). RESULTS: A total of 1172 women were eligible for this study, of which 281 (24.0%) were aged ≤35 years, 22.9% illiterate, 43.6% employed, 89.5% married, and 38.1% were obese. Grade III tumors constituted 38.4% of cases. Tumor stage I was 7.5%; II, 50.7%; II, 30.9%; IV, 11.1%. We have shown strong association between breast cancer among Arab females and obesity (OR =2.29, 95% CI 1.68-3.13), positive family history of breast cancer (OR =2.31, 95% CI 1.60 - 3.32), the use of hormonal replacement therapy (OR =2.25, 95% CI 1.65 - 3.08), post-menopause (OR =1.72, 95% CI 1.25 - 2.38), lack of education (OR =9.09, 95% CI 5.88 - 14.29), and never breastfeed (OR =1.89, 95% CI 1.19 - 2.94). CONCLUSION: These results indicate the presence of classical risk factors established in the western countries, and also some specific ones, which may result from genetic and/or environmental factors. Thereby, these findings will be of great value to establish adequate evidence-based awareness and preventative measures in the Arab world.

Age-specific gene expression signatures for breast tumors and cross-species conserved potential cancer progression markers in young women.

Breast cancer in young women is more aggressive with a poorer prognosis and overall survival compared to older women diagnosed with the disease. Despite recent research, the underlying biology and molecular alterations that drive the aggressive nature of breast tumors associated with breast cancer in young women have yet to be elucidated. In this study, we performed transcriptomic profile and network analyses of breast tumors arising in Middle Eastern women to identify age-specific gene signatures. Moreover, we studied molecular alterations associated with cancer progression in young women using cross-species comparative genomics approach coupled with copy number alterations (CNA) associated with breast cancers from independent studies. We identified 63 genes specific to tumors in young women that showed alterations distinct from two age cohorts of older women. The network analyses revealed potential critical regulatory roles for Myc, PI3K/Akt, NF-κB, and IL-1 in disease characteristics of breast tumors arising in young women. Cross-species comparative genomics analysis of progression from pre-invasive ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) revealed 16 genes with concomitant genomic alterations, CCNB2, UBE2C, TOP2A, CEP55, TPX2, BIRC5, KIAA0101, SHCBP1, UBE2T, PTTG1, NUSAP1, DEPDC1, HELLS, CCNB1, KIF4A, and RRM2, that may be involved in tumorigenesis and in the processes of invasion and progression of disease. Array findings were validated using qRT-PCR, immunohistochemistry, and extensive in silico analyses of independently performed microarray datasets. To our knowledge, this study provides the first comprehensive genomic analysis of breast cancer in Middle Eastern women in age-specific cohorts and potential markers for cancer progression in young women. Our data demonstrate that cancer appearing in young women contain distinct biological characteristics and deregulated signaling pathways. Moreover, our integrative genomic and cross-species analysis may provide robust biomarkers for the detection of disease progression in young women, and lead to more effective treatment strategies.

Gene expression profiling in women with breast cancer in a Saudi population.

OBJECTIVE: To generate consensus gene expression profiles of invasive breast tumors from a small cohort of Saudi females, and to explore the possibility that they may be broadly conserved between Caucasian and Middle Eastern populations. METHODS: This study was performed at King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia, from January 2005 to January 2007. Gene expression profiles were generated from 38 invasive breast tumors, and 8 tumor adjacent tissues TATs using BD Atlas cDNA expression arrays containing 1176 genes. Results were confirmed by reverse transcriptase polymerase chain reaction, and analyzed by 2-dimensional unsupervised hierarchical clustering. RESULTS: The analysis identified 48 differentially expressed genes in tumors from which 25 are already reported by various western studies. Forty-three of these genes were also differentially expressed in TATs. The same data set has been able to distinguish between tumors and the TATs, interestingly by using only 4 of the differentially expressed genes. Moreover, we were able to group the patients according to prognosis to an extent by hierarchical clustering. CONCLUSION: Our results indicate that expression profiles between Saudi females with breast cancer and the Caucasian population are conserved to some extent, and can be used to classify patients according to prognostic groups. We also suggest 3 differentially-expressed genes IGHG3, CDK6, and RPS9 in tumors may have a novel role in breast cancer. In addition, the role of TATs is much more essential in breast cancer, and needs to be explored thoroughly.

Expression of B7-H1 in breast cancer patients is strongly associated with high proliferative Ki-67-expressing tumor cells.

B7-H1, a co-inhibitory molecule, plays a role in immune escape of tumors. We have shown previously the expression of this molecule in breast cancer patients and demonstrated its association with high histological grade, progesterone and estrogen receptor negative status, all of which are known to have direct impact on cell proliferation. In the present work, we investigated the effect of proliferation, as measured by Ki-67 and mitotic count, on the induction of B7-H1. We used H&E stained sections to score for mitotic count in 69 breast cancer patients. Immunohistochemistry was used to investigate B7-H1 and Ki-67 expression. The relationship between B7-H1 induction and cell proliferation was further investigated in primary cultured cells. B7-H1 expression was recorded in patients with a high mitotic index (p = 0.007). There was a high significant correlation between B7-H1 expression and the presence of the proliferative marker Ki-67 (p < 0.001) indicating the association of proliferation with B7-H1 induction. Furthermore, B7-H1 was gradually induced in proliferating cells of 8/8 primary cell lines as measured by Ki-67 expression. Finally, B7-H1 was downregulated in quiescent cells and upregulated in cells stimulated with a mitogen confirming the association of proliferation with the induction of B7-H1. We have shown for the first time a direct association between proliferation and the expression of B7-H1 in breast cancer patients. The relationship between B7-H1 induction and cell proliferation was also thoroughly investigated in vitro, in which a strong link between B7-H1 expression and the presence of the proliferative Ki-67 marker was clearly demonstrated.

Gene expression profiles of the fibroblasts from breast tumors and normal tissue compared with the tumor expression profiles.

OBJECTIVE: The study was designed to examine whether the gene expression profiles of fibroblast cell lines, established from the tumor and the normal tissue from the same breast, exhibit any similarities with the profiles of the original tissues. METHODS: Fibroblast cell lines were established from invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS) of the breast and the adjacent normal tissues. Isolated total RNA from the cell lines and tissues were used to prepare labeled cDNA which was hybridized to Becton Dickinson Atlas microarrays for obtaining profiles of expressed genes. The profiles of tumors and cell lines were compared. This study was carried out at King Faisal specialist Hospital and Research Center, Riyadh, Kingdom of Saudi Arabia, during 2004 and 2005. RESULTS: Alterations of expression of most of the genes in the tissues were not detectable in the cell lines. The expression of a lower number of genes was altered in DCIS compared with that in IDC tumors. CONCLUSION: Although the fibroblasts discharge important functions, their gene expression profiles do not represent the breast tissue to the extent that any prognostic decisions could be made.

The B7-H1 (PD-L1) T lymphocyte-inhibitory molecule is expressed in breast cancer patients with infiltrating ductal carcinoma: correlation with important high-risk prognostic factors.

B7-H1 molecule increases the apoptosis of tumor-reactive T lymphocytes and reduces their immunogenicity. Breast cancer is the second most common cause of mortality after lung cancer. Direct evidence linking B7-H1 with cancer has been shown in several malignancies; however, its expression in breast cancer has not been investigated. We used immunohistochemistry to investigate the expression of the B7-H1 molecule in 44 breast cancer specimens and to study its correlation with patients' clinicopathological parameters. The expression of B7-H1 was shown in 22 of 44 patients and was not restricted to the tumor epithelium (15 of 44, 34% in tumor cells), but was also expressed by tumor-infiltrating lymphocytes (TIL; 18 of 44, 41%). Interestingly, intratumor expression of B7-H1 was significantly associated with histologic grade III-negative (P = .012), estrogen receptor-negative (P = .036), and progesterone receptor-negative (P = .040) patients. In addition, the expression of B7-H1 in TIL was associated with large tumor size (P = .042), histologic grade III (P = .015), positivity of Her2/neu status (P = .019), and severe tumor lymphocyte infiltration (P = .001). Taken together, these data suggest that B7-H1 may be an important risk factor in breast cancer patients and may represent a potential immunotherapeutic target using monoclonal antibody against the B7-H1 molecule.

Quick gene expression profiling of promyelocytic cell line HL-60.

OBJECTIVE: A number of techniques have been developed to perform gene expression profiling. We report preliminary results from our exploratory study, using sequential analysis of gene expression (SAGE) technique, to profile the undifferentiated and differentiated HL-60 cells in line with our interest to characterize the cancer phenotype. The aim of the study is to evaluate the technique and to understand the molecular bases of these 2 states of cells. METHODS: HL-60 cells were differentiated after treatment with dimethyl sulfoxide. Tag libraries were prepared from the messenger RNAs of the undifferentiated and differentiated cells according to the SAGE protocol. The search for genes corresponding to the tags was carried out using SAGE software. The tags and the genes from the 2 libraries were compared for their levels of expression. The study was carried out at the King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia during the year 2001. RESULTS: A comparison of tags from the 2 libraries revealed that 151 tags corresponding to 57 genes expressed differentially: 60 tags were elevated and 59 were repressed in the undifferentiated cells. Thirty-two tags were equally expressed in both types of cells. Of the corresponding genes, 25 were expressed at higher, 17 at lower, while 15 were expressed at comparable levels in both cell types. In the profile of undifferentiated cells, the genes involved in mitochondrial function and protein synthesis were prominent, while in the differentiated cells, the genes coding for proteins associated with cell membranes, signal transduction and for cell specific functions were prominent. The genes, expressed equally in both the cell types, were concerned with the maintenance of the living state. CONCLUSION: Sequential analysis of gene expression is a useful technique for gene expression profiling. As previously indicated by others, a dedicated team can generate useful data within reasonable time limits.