Saad Eissa

Serum organochlorine levels and history of lactation in Egypt

We conducted a study in Egypt to assess the determinants of organochlorine serum levels among premenopausal women and the risk of premenopausal breast cancer for women with high organochlorine serum levels. We included 69 breast cancer patients and 53 controls consisting of visitors to the hospitals of the cancer patients. We found low levels of dichlorodiphenyldichloroethylene (DDE), total dichlorodiphenyltrichloroethane, and beta-hexacholorhexane (beta-HCH) in most subjects. Mean DDE levels were 12.7 +/- 20.3 ppb for cases and 16.6 +/- 30.1 ppb for controls (P = 0.60); beta-HCH levels were 2.1 +/- 3.8 ppb for patients and 2.1 +/- 3.9 ppb for controls (P = 0.71). Interestingly, subjects with low levels had breast fed their children for an average period of 18 months. Women with no lactation history had much higher organochlorine levels than women who breast fed (P = 0.002 for DDE). Younger age, older age at first childbirth, and shorter duration of breast feeding were significant predictors of higher levels of serum DDE levels. Younger age, older age at first childbirth, and higher body mass index were significant predictors of higher beta-HCH levels. This study suggests that organochlorine serum levels in Egyptian women are quite low, but indicates an effect of breast feeding in eliminating organochlorines, which would imply exposure to children. Organochlorine serum level was not a risk factor of breast cancer in this population.

DNA Copy Number Changes in Schistosoma-Associated and Non-Schistosoma-Associated Bladder Cancer

DNA copy number changes were investigated in 69 samples of schistosoma-associated (SA) and non-schistosoma-associated (NSA) squamous cell carcinoma (SCC) and transitional cell carcinoma (TCC) of the bladder by comparative genomic hybridization (CGH). DNA copy number changes were detected in 47 tumors. SA tumors had more changes than NSA tumors (mean, 7 vs. 4), whereas the number of changes in SCC and TCC tumors was similar. SA tumors displayed more gains than losses (1.7:1), whereas NSA tumors showed an equal number of gains and losses. Changes that were observed at similar frequencies in SCC and TCC, irrespective of the schistosomal status, included gains and high-level amplifications at 1q, 8q, and 20q and losses in 9p and 13q. These changes may be involved in a common pathway for bladder tumor development and progression independent of schistosomal status or histological subtype. Losses in 3p and gains at 5p were seen only in SCC (P < 0.01) and losses in 5q were more frequent in SA-SCC than in other tumors (P < 0.05). However, changes that were more frequent in TCC than those in SCC included gains at 17q (P < 0.01) and losses in 4q (P < 0.05) and 6q (P < 0.01). Gains and high-level amplifications at 5p were seen only in SA-SCC (P < 0. 01), whereas gains and high-level amplifications with minimal common overlapping regions at 11q13 were more frequently seen both in SA-SCC and SA-TCC tumors (P < 0.01). In addition to the above mentioned alterations, several other changes were also seen at lower frequencies. The variations in the DNA copy number changes observed in TCC, SCC, SA, and NSA bladder carcinomas suggest that these tumors have different genetic pathways.

High levels of oxidative DNA damage in lymphocyte DNA of premenopausal breast cancer patients from Egypt

Egypt shows a parallel increase in premenopausal breast cancer and environmental pollution. The purpose of this study is to explore a possible relationship between oxidative DNA damage, urinary estrogen metabolites and breast cancer in Egyptian premenopausal women. We conducted a pilot study of Egyptian breast cancer involving 29 cases and 32 controls and analysed lymphocyte DNA levels of 7,8-dihydro-8-oxo-2′-deoxyguanine (8-oxo-dG), a measure of oxidative DNA damage using high performance liquid chromatography with electro-chemical detection (HPLC-ECD) method. We analysed levels of urinary estrogen metabolites, 2-hydroxyestrone (2-OHE) and 16α-hydroxyestrone (16α-OHE) by an enzyme immuno assay. We also collected residential, occupational, and reproductive histories of all study subjects. We detected, in all subjects, exceptionally high levels of 8-oxo-dG and thus oxidative DNA damage, the levels (mean 8-oxo-dG/105 dG ± SD) were significantly (P < 0.01) higher in breast cancer cases (139.4 ± 78.4) than in controls (60.9 ± 51.5). Urinary 2-OHE and 16α-OHE or their ratio was not significantly different between cases and controls. However, 8-oxo-dG levels were positively correlated (P < 0.05) with 2-OHE and 16α-OHE from cases while controls showed a negative correlation (P < 0.05). Urban residence (Odds Ratio [OR] 3.1; Confidence interval [CI], 1.1 – 9.3), infertility (OR [9.8]; CI [1.1 – 89.7]), age (OR [2.6]; CI [1.4 – 4.6]) and 8-oxo-dG (OR 5.8; CI 1.9 – 17.5) levels were found to be significant predictors of breast cancer. Our finding of exceptionally high levels of 8-oxo-dG, a common result of oxidative DNA damage, warrant future studies on a larger population of premenopausal women in Egypt with consideration of other susceptibility markers and dietary characteristics.

Somatic FGF9 mutations in colorectal and endometrial carcinomas associated with membranous β-catenin†

We previously described striking molecular features including high frequency of membranous β‐catenin in subsets of familial colon cancers with as yet unknown predisposition. We hypothesized that such tumors might carry mutations in Wnt/β‐catenin target genes. Fibroblast growth factor 9 (FGF9) was an attractive target, as it maps to a common area of loss of heterozygosity (LOH) in colorectal carcinomas on 13q12.11. Here, we report, for the first time, the occurrence of FGF9 mutations in human cancers. We found a total of six distinct FGF9 mutations including one frameshift, four missense, and one nonsense, in 10 (six colorectal and four endometrial) out of 203 tumors and cell lines. The frameshift mutation was detected in five different tumors. Mapping of these mutations onto the crystal structure of FGF9 predicted that they should all lead to loss of function albeit through variable mechanisms. The p.R173K mutation should diminish ligand affinity for heparin/heparan sulfate, the p.V192M, p.D203G, and p.L188YfsX18 (FGF9Δ205–208) mutations should negatively impact ligands interaction with receptor, while p.G84E and p.E142X (FGF9Δ142–208) mutations should interfere with ligand folding. Consistent with these structural predictions, the p.V192M, p.D203G, and p.L188YfsX18 (FGF9Δ205–208) mutations impaired the ability of ligand to activate mitogen‐activated protein kinase (MAPK) cascade in cultured cells expressing FGF receptors. LOH was observed in seven out of nine FGF9 mutant tumors, supporting the predicted loss of function. Interestingly, eight out of 10 (80%) of the FGF9 mutant tumors showed normal membranous β‐catenin expression and the absence of mutation in the β‐catenin gene (CTNNB1). These data suggest that FGF9 plays a role in colorectal and endometrial carcinogenesis. Hum Mutat 29(3), 390–397, 2008.

Analysis of RhoC expression and lymphovascular emboli in inflammatory vs non-inflammatory breast cancers in Egyptian patients

Understanding the molecular factors that distinguish inflammatory breast cancer (IBC) from non-IBC is important for IBC diagnosis. We reviewed the records of 48 IBC patients and 64 non-IBC patients from Egypt. We determined RhoC expression and tumor emboli and their relationship to demographic and reproductive characteristics. Compared with non-IBC patients, IBC patients had significantly lower parity (P=0.018) and fewer palpable tumors (P<0.0001). IBC tumors showed RhoC overexpression more frequently than non-IBC tumors (87% vs. 17%, respectively) (P<0.0001). Tumor emboli were significantly more frequent in IBC tumors than non-IBC tumors (Mean+/- SD: 14.1+/-14.0 vs. 7.0+/-12.9, respectively) (P<0.0001). This study illustrates that RhoC overexpression and tumor emboli are more frequent in tumors of IBC relative to non-IBC from Egypt. Future studies should focus on relating epidemiologic factors to molecular features of IBC in this population.

Distinct Genetic and Epigenetic Signatures of Colorectal Cancers According to Ethnic Origin

Background: The outcome of colorectal cancer varies depending on ethnic origin. Egyptian colorectal carcinoma is surprisingly young-age disease with high proportion of rectal and advanced stage cancers. Methods: We characterized 69 sporadic Egyptian colorectal cancers for promoter methylation at 24 tumor suppressor genes, microsatellite instability, and expression of mismatch repair, p53, and β-catenin proteins. Data were compared with 80 Western colorectal carcinoma of sporadic and familial origin from Finland. Results: Egyptian colorectal carcinomas showed significantly higher methylation of the microsatellite stable (MSS) tumors as reflected by the average number of methylated genes per case (P = 0.00002) and tumor suppressor gene methylator phenotype (TSGMP), defined here as methylation of ≥5 genes, (P = 0.0001) compared with the sporadic Western cancers. The TSGMP was associated with advanced stage in the Egyptian cancers (P = 0.0016). Four genes were differentially methylated between Egyptian and Western cases, of which the association of CDKN2B/p15 methylation with Egyptian origin was outstanding (P = 4.83E-10). Egyptian carcinoma also showed significantly lower frequency of nuclear β-catenin localization than the sporadic Western cancers (P = 0.00006) but similar to that of the familial Western subset designated as familial colorectal cancer type X. Conclusions: We show novel pathway in colon carcinogenesis marked by high methylation of MSS cancers, remarkable CDKN2B/p15 methylation, and low frequency of Wnt signaling activation. Impact: Our findings highlight the possible effect of environmental exposures in carcinogenesis through DNA methylation and should have applications in prevention, molecular diagnosis, prognosis, and treatment. Cancer Epidemiol Biomarkers Prev; 21(1); 202–11. ©2011 AACR.

Pedunculated Endocardial Left Ventricular Fibroma Presenting With Cerebral and Bilateral Peripheral Embolization

Left ventricular fibroma is a rare benign tumour of the heart. We present the case of a 24-year-old man with left hemiplegia and bilateral popliteal artery occlusion associated with left ventricular mass. The patient underwent successful excision of a pedunculated mass attached to the trabeculae of left ventricular cavity. Histopathologic examination confirmed the presence of fibroma associated with septic thrombus. The association of fibroma and embolization is rare.

Loss of p15(INK4b) Expression in colorectal cancer is Linked to Ethnic Origin

Colorectal cancers remain to be a common cause of cancer-related death. Early-onset cases as well as those of various ethnic origins have aggressive clinical features, the basis of which requires further exploration. The aim of this work was to examine the expression patterns of p15INK4b and SMAD4 in colorectal carcinoma of different ethnic origins. Fifty-five sporadic colorectal carcinoma of Egyptian origin, 25 of which were early onset, and 54 cancers of Finnish origin were immunohistochemically stained with antibodies against p15INK4b and SMAD4 proteins. Data were compared to the methylation status of the p15INK4b gene promotor. p15INK4b was totally lost or deficient (lost in ≥ 50% of tumor cell) in 47/55 (85%) tumors of Egyptian origin as compared to 6/50 (12%) tumors of Finnish origin (p=7e-15). In the Egyptian cases with p15INK4b loss and available p15INK4b promotor methylation status, 89% of cases which lost p15INK4b expression were associated with p15INK4b gene promotor hypermethylation. SMAD4 was lost or deficient in 25/54 (46%) tumors of Egyptian origin and 28/48 (58%) tumors of Finnish origin. 22/54 (41%) Egyptian tumors showed combined loss/deficiency of both p15INK4b and SMAD4, while p15INK4b was selectively lost/deficient with positive SMAD4 expression in 24/54 (44%) tumors. Loss of p15INK4b was associated with older age at presentation (>50 years) in the Egyptian tumors (p=0.04). These data show for the first time that p15INK4b loss of expression marks a subset of colorectal cancers and ethnic origin may play a role in this selection. In a substantial number of cases, the loss was independent of SMAD4 but rather associated with p15INK4b gene promotor hypermethylation and old age which could be related to different environmental exposures.

Assessment of Her-2/neu gene amplification status in breast carcinoma with equivocal 2+ Her-2/neu immunostaining

BACKGROUND AND PURPOSE Amplification of Her-2/neu gene occurs in 25-30% of breast carcinomas. FDA approved trastuzumab (Herceptin) is effective only in tumors having the gene amplification. Immunohistochemistry (IHC) for Her-2/neu protein is widely used but false positive and false negative results exist. Fluorescence in-situ hybridization (FISH) has both excellent sensitivity and specificity in detecting Her-2/neu amplification. Comparative studies have shown discordant results in proportion of cases with equivocal 2+ immunostain. This study is thus conducted to ascertain the frequency of Her-2/neu gene amplification by FISH in breast carcinoma specified as score 2+ by IHC and to correlate these findings with parameters of prognosis in breast cancer. METHODS From October 2008 till May 2010 all paraffin blocks from cases with invasive breast carcinoma which were scored as 2+ by IHC were eligible for the study, there were 50 cases. Immunohistochemical evaluation of Her-2/neu was performed using the HercepTest. All cases were immunohistochemically evaluated for ER and PR. FISH was performed using FDA approved Path-Vysion Her-2/neu/CEP 17 dual color probe. RESULTS Nine cases (18%) out of 50 cases scored as Her-2/neu 2+ by IHC showed true gene amplification with a median value of scoring ratio 4.28 ranging from 2.37 to 13.26. Another two cases showed low level of amplification but when corrected for Her-2/neu/CEP ratio they did not show true amplification as they were associated with polysomy 17. With the exception of tumor size, neither patients age, histologic grade nor lymph node status were correlated with Her-2/neu gene amplification. Significant inverse correlation existed between Her-2/neu gene amplification and ER (P=0.01), PR status (P<0.001). CONCLUSION Even though FISH is a more complex and expensive procedure, it should be considered the method of choice for assessment of Her-2/neu gene status especially for equivocal cases by IHC that are not accompanied by true gene amplification in the majority of breast carcinoma cases.

Survival of Inflammatory Breast Cancer Patients Compared to Non‐inflammatory Breast Cancer Patients in Egypt

To the Editor: Inflammatory Breast Cancer (IBC) is a rare but aggressive form of breast cancer that is diagnosed clinically (1). IBC has characteristic clinical and biologic features suggestive of differences between IBC and non-IBC. Egypt has about a five times higher proportion of IBC patients than the USA (2‐4) with distinct molecular features of IBC tumors that may reflect a more aggressive nature of the disease (5,6). Within Egypt, there have been no past comparisons between IBC and non-IBC patients with respect to survival. Therefore, as a part of this study, we decided to compare survival of IBC and non-IBC patients while taking into account, the epidemiologic, pathologic, and treatment characteristics of these two groups of patients from the National Cancer Institute of Cairo University (NCI-Cairo) in Egypt. Patients included in this study were diagnosed and treated at NCI-Cairo from 2000 to 2005. The patients included two groups, 65 IBC patients and 52 non-IBC patients. IBC diagnosis was based on the presence of erythema, edema, and peau d’orange and some of the patients in this study were included in our previous studies (5,6). We reviewed the medical records, pathology reports and radiation records, and