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Biomedical subjects

Adnan Ezzat

Publications and source records attributed to Adnan Ezzat.

16 recordsLinked to original sources

Role of phosphatidylinositol 3'-kinase/AKT pathway in diffuse large B-cell lymphoma survival.

Phosphatidylinositol 3'-kinase (PI3K) is a key player in cell-growth signaling in a number of lymphoid malignancies, but its role in diffuse large B-cell lymphoma (DLBCL) has not been fully elucidated. Therefore, we investigated the role of the PI3K/AKT pathway in a panel of 5 DLBCL cell lines and 100 clinical samples. Inhibition of PI3K by a specific inhibitor, LY294002, induced apoptosis in SUDHL4, SUDHL5, and SUDHL10 (LY-sensitive) cells, whereas SUDHL8 and OCI-LY19 (LY-resistant) cells were refractory to LY294002-induced apoptosis. AKT was phosphorylated in 5 of 5 DLBCL cell lines and inhibition of PI3K caused dephosphorylation/inactivation of constitutively active AKT, FOXO transcription factor, and GSK3 in LY-sensitive cell lines. In addition, there was a decrease in the expression level of inhibitory apoptotic protein, XIAP, in the DLBCL cell lines sensitive to LY294002 after treatment. However, no effect was observed in XIAP protein levels in the resistant DLBCL cell lines following LY294002 treatment. Finally, using immunohistochemistry, p-AKT was detected in 52% of DLBCL tumors tested. Furthermore, in univariate analysis, high p-AKT expression was associated with short survival. In multivariate analysis, this correlation was no longer significant. Altogether, these results suggest that the PI3K/AKT pathway may be a potential target for therapeutic intervention in DLBCL.

Apoptosis↗

HER2, TOP2A, CCND1, EGFR and C-MYC oncogene amplification in colorectal cancer.

AIM: Recent studies had suggested substantial molecular differences between tumours from different ethnic groups. In this study, the molecular differences between the incidences of colorectal carcinoma in Saudi and Swiss populations are investigated. METHOD: 518 cases of colon cancer tumours (114 from Saudi Arabia and 404 from Switzerland) were analysed in a tissue microarray format. Fluorescence in situ hybridisation (FISH) was used to estimate frequencies of copy number changes of known oncogenes, including HER2, TOPO2A, CCND1, EGFR and C-MYC. RESULTS: Using FISH, amplifications were mostly low level (gene-to-centromere ratio 2 to 4), which is in contrast with other tumour types with more frequent gene amplifications. The amplifications were particularly frequent for MYC (Saudi 9% and Swiss 14.2%) but unrelated to clinical outcome and pathological information. Remarkably, there were four tumours exhibiting classic high-level gene amplification for HER2 (Swiss 1.3%), a pattern often accompanied by response to trastuzumab (Herceptin) in breast cancer. Occasional high-level amplifications were also observed for CCND1 (Saudi 1/106, 0.9%; Swiss 2/373, 0.5%) and EGFR (Swiss 2/355; 0.6%). CONCLUSIONS: Rare high-level amplifications of therapeutic target genes were found in patients with colon cancer. Although no molecular differences were found between incidences of colon cancer cases in Swiss and Saudi populations, these observations emphasise the urgent need for clinical studies investigating the effect of targeted therapies.

Adult↗

High throughput tissue microarray analysis of FHIT expression in diffuse large cell B-cell lymphoma from Saudi Arabia.

Recent studies have suggested a potential prognostic role of alterations of the fragile histidine triad (FHIT) gene in diffuse large B-cell lymphoma. To evaluate possible mechanisms of FHIT inactivation and to further clarify its potential prognostic relevance, we analyzed a set of 114 diffuse large B-cell lymphoma with clinical follow-up information. Tissue microarrays were analyzed by immunohistochemistry for protein expression, and corresponding DNA samples were analyzed for FHIT promotor hypermethlyation. Reduced or absent FHIT expression was found in 75 of 114 diffuse large B-cell lymphoma (66%), but was unrelated to clinical tumor stage or patient prognosis. FHIT promotor hypermethylation was observed in 29 of 93 (23%) interpretable diffuse large B-cell lymphoma. Hypermethylation was not significantly correlated to protein expression loss, which could be explained by competing mechanisms for FHIT inactivation in a substantial fraction of non FHIT hypermethylated diffuse large B-cell lymphoma. Hypermethylation was significantly associated with poor prognosis of diffuse large B-cell lymphoma patients and predominantly seen in nongerminal center diffuse large B-cell lymphoma (27%), but less frequent (13%) in germinal center diffuse large B-cell lymphoma. In summary, these data suggest that promotor hypermethylation is responsible for reduced FHIT expression in a substantial subset of diffuse large B-cell lymphoma, which is primarily composed of nongerminal center subtype with poor patient prognosis.

Acid Anhydride Hydrolases↗

High epidermal growth factor receptor amplification rate but low mutation frequency in Middle East lung cancer population.

Epidermal growth factor receptor (EGFR) exon 18-21 mutations were shown to be highly predictive of response to gefitinib (Iressa) therapy in lung cancer. Studies on Western and Japanese lung cancers have indicated substantial differences in the EGFR mutation frequency between these populations. To investigate the prevalence of EGFR in another distinct ethnic group, EGFR alterations were studied in 47 consecutive non small cell lung cancers from Saudi Arabia by immunohistochemistry, fluorescence in situ hybridization, and DNA sequencing. Detectable EGFR expression was seen in 69.8% of 43 interpretable cancers. Epidermal growth factor receptor amplification, present in 15.3% of 39 analyzable cancers, was strongly associated with high levels of EGFR expression (P = .0047). Only 1 exon 18-21 mutation was seen among 34 lung cancers that could be successfully sequenced. It is concluded that EGFR exon 18-21 mutations are rare in Middle East patients with lung cancer and occur in a similar range as in Western patients. The remarkable high rate of EGFR gene amplifications could potentially facilitate studies on the predictive role of gene copy number changes for response to anti-EGFR therapies in Middle East patient sets.

Adenocarcinoma↗

High frequency and strong prognostic relevance of O6-methylguanine DNA methyltransferase silencing in diffuse large B-cell lymphomas from the Middle East.

Several clinically relevant molecular classifiers of diffuse large B-cell lymphoma (DLBCL) have recently been demonstrated in Western populations. However, substantial molecular differences have recently been shown between tumors derived from different ethnic groups. To investigate prevalence and interrelationship of recently suggested molecular prognostic markers in Middle East DLBCL, we analyzed coexpression of CD10/Bcl6 (by immunohistochemistry), t(14;18) translocations (by fluorescence in situ hybridization), and methylation of the gene encoding the DNA repair enzyme O(6)-methylguanine DNA methyltransferase (MGMT) in a series of 190 DLBCL patients from Saudi Arabia with clinical follow-up data. Coexpression of CD10/Bcl6 (germinal center-like immunophenotype) was found in 13%, t(14;18) translocations in 17.9%, and MGMT methylation in 75.9% of cases. There was a trend toward better prognosis (although statistically insignificant) in tumors with coexpression of CD10/Bcl6. MGMT methylation were significantly related to good prognosis. The combined analysis of both parameters revealed that MGMT methylation was independent of immunophenotype and remained a significant predictor of prognosis in nongerminal center-like DLBCL subgroup. t(14;18) was significantly associated with CD10/Bcl6 coexpression (46.7%) but infrequent in CD10-/Bcl6-negative lymphomas (9.4%; P = .0073). However, t(14;18) was unrelated to clinical outcome. In summary, our data suggest a strong prognostic importance of MGMT methylation independent of DLBCL immunophenotype. Based on previous data from Western patients, the rate of MGMT hypermethylation was higher, and the portion of germinal center-like DLBCL was lower than expected. These results provide evidence for molecular differences between Saudi Arabian and Western DLBCL.

Chromosomes, Human, Pair 14↗

Epstein-Barr virus infection is not the sole cause of high prevalence for Hodgkin's lymphoma in Saudi Arabia.

The age-adjusted incidence of Hodgkin's lymphoma (HL) is markedly higher in Saudi Arabia than in the USA, and accounts for 10.5% of all neoplasias in children aged 15 years or older in Saudi Arabia. Epstein-Barr virus (EBV) infection has been suspected to cause high HL incidence in developing countries. To investigate the role of EBV for the high frequency of HL in Saudi Arabia, we analysed 169 HLs from Saudi Arabia and 30 HLs from Europe for EBV infection by in situ hybridization with fluorescence in-conjugated EBV on tissue microarray sections. All Saudi Arabian and European HLs were analysed in one experiment under identical conditions. Unexpectedly, our data show only minor, insignificant differences in EBV infection rates between Saudi Arabian (42 out of 147 informative cases 28.6%) and European HL (nine out of 30 informative cases; 30%; P = 0.8752). Within the Saudi Arabian population, EBV infection was most frequently seen in mixed cellularity HL (52.4%). This was significantly more frequent than in nodular sclerosing HL (26.1%; P = 0.0236). EBV positivity was unrelated to patient prognosis. In conclusion, our data strongly suggest that EBV is not the main cause for the high prevalence of HL in Saudi Arabia. This would be consistent with a major role of genetic susceptibility genes for HL in these populations. The Saudi Arabian population, with high consanguinity and large families, would prove ideal for identifying HL susceptibility genes.

Adolescent↗

Prevalence of fragile histidine triad expression in tumors from saudi arabia: a tissue microarray analysis.

AIM: The fragile histidine triad (FHIT) gene was discovered and proposed as a tumor suppressor gene for most human cancers. It encodes the most active common human chromosomal fragile region, FRA3B. We studied the prevalence of loss of FHIT expression in various tumors and correlated its loss with various clinicopathologic features. METHODS: To determine whether the absence of FHIT expression correlates with clinical variables such as grade, stage, and survival time, we assessed FHIT expression using immunohistochemistry. More than 1,800 tumors from more than 75 tumor categories were analyzed by immunohistochemistry in a tissue microarray format. RESULTS: Loss of FHIT expression ranged from 19% in ovarian tumors to 67% in lung cancers. Clinical and pathologic features like grade, stage, tumor size, and lymph node metastasis showed correlation with loss of FHIT expression in some tumors. No difference was seen in the survival patterns and loss of FHIT expression in any of the tumor groups studied. CONCLUSIONS: Loss of FHIT expression is an ubiquitous event in the multistep, multifactorial carcinogenesis process. FHIT may be altered at different stages in different types of cancers. Most of the tumors with a wider prevalence of loss of FHIT expression as an early event show a correlation with clinicopathologic features. However, in some of the tumors, FHIT expression is lost as a late event and is only seen in a fraction of the tumors.

Acid Anhydride Hydrolases↗

The impact of the World Health Organization classification and clonality assessment of posttransplant lymphoproliferative disorders on disease management.

CONTEXT: The World Health Organization classification of posttransplant lymphoproliferative disorders divides them into 4 main categories. OBJECTIVE: To classify cases of posttransplant lymphoproliferative disorders diagnosed in our institution according to the World Health Organization scheme and correlate the classification and clonality with clinical data. DESIGN: Cases of posttransplant lymphoproliferative disorders were reviewed. They were classified according to the World Health Organization scheme. Clonality was determined by flow cytometry and/or polymerase chain reaction. Patients' charts were reviewed. RESULTS: Thirty-one cases were identified. Median age was 33 years. There were 19 cases of kidney, 8 cases of liver, and 4 cases of bone marrow transplant. Immunosuppression consisted of cyclosporin A and prednisone (N = 24) or FK506 and prednisone (N = 7). Twenty cases (63%) were World Health Organization type 3, 7 cases (23%) type 2, 3 cases (6.4%) type 1, and 1 case type 4 posttransplant lymphoproliferative disorder. Ten patients received chemotherapy, 20 patients had reduction of immunosuppression, and 1 had no treatment. Follow-up was available on 25 patients. Seven (43.75%) of 16 with type 3 lesions with available follow-up died of their disease. Five of these patients received reduction of immunosuppression alone. Only 2 of 9 patients with type 3 disease who received chemotherapy died of disease. Two patients with type 2 disease died of unrelated causes. One patient is alive with disease; the remaining patients with types 1 and 2 disease are alive with no disease. CONCLUSIONS: The World Health Organization classification of posttransplant lymphoproliferative disorders is valuable in the identification of subtypes. It helps identify early lesions (1 and 2) requiring reduction of immunosuppression and type 3 disease, which requires chemotherapy from the outset.

Adolescent↗

VIP (etoposide, ifosfamide, cisplatin) in adult patients with recurrent or refractory Ewing sarcoma family of tumors.

Despite the fact that Ewing sarcoma family of tumors (ET) is chemosensitive, long-term survival is extremely rare for patients with primary refractory or recurrent disease. There is no standard salvage chemotherapy regimen available in this context. In this study the authors reviewed their experience with the combination of etoposide, ifosfamide, and cisplatin in adult patients with recurrent or refractory disease. From February 1997 through December 2001, they evaluated the efficacy of etoposide (75 mg/m2/day for 5 days), ifosfamide (1,200 mg/m2/day for 5 days), and cisplatin (20 mg/m2/day for 5 days) combination chemotherapy (VIP regimen), as second-line salvage therapy in 27 patients with recurrent or refractory ET. All patients were evaluated for response, time to progression, and overall survival. Twenty-one male and 6 female patients with recurrent (n = 14) and refractory (n = 13) disease were treated with the VIP regimen. Median age was 18 years (range, 16-34 years). Twenty-two patients were previously treated with vincristine, Adriamycin, ifosfamide, and actinomycin-D; and 5 patients were treated with cyclophosphamide, Adriamycin, and vincristine. Sites of recurrent or progressive disease included local (n = 3), distant (n = 11), and both local and distant (n = 13). A total of 129 cycles of VIP were given (median, 5 cycles/patient; range, 1-14 cycles/patient). One patient (4%) had a complete response (CR) and 8 patients (30%) had a partial response (PR), for an overall response rate of 34%. The median number of cycles given to patients with CR + PR was 6 (range, 3-14 cycles). Nine patients (33%) had stable disease and 9 (33%) had disease progression. Median time to progression and median overall survival were 6.6 months and 8.1 months respectively for all patients, and 12.8 months and 14.2 months respectively for responders. There were no toxic deaths. Major toxicities included grade IV granulocytopenia in 19 patients and grades III/IV thrombocytopenia in 15 patients. At a median follow-up of 8 months (range, 2-56 months), 24 patients died of disease progression, 2 patients are alive with disease, and 1 patient is alive with no evidence of disease. The authors conclude that the VIP combination is active in patients with recurrent/refractory ET, with acceptable toxicity, and offers good palliation. Cisplatin-based combination chemotherapy merits further investigation, possibly as first-line treatment in this disease.

Adolescent↗

18-Fluorodeoxyglucose-positron emission tomography in inflammatory breast cancer.

Inflammatory breast cancer (IBC) is the most aggressive form of locally advanced breast cancer. It can be diagnosed based on a clinical or pathologic basis. We evaluated the usefulness of (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) scans for diagnosing and staging IBC. We retrospectively reviewed the medical records of seven consecutive patients with IBC who underwent FDG-PET scanning for the initial staging. Four patients had follow-up PET scans after chemotherapy. All seven patients presented with diffuse breast enlargement, redness, and peau d'orange for 1 to 5 months' duration. In addition, four patients had a palpable breast mass, and three had axillary lymph node enlargement. Mammography showed diffuse, increased parenchymal density and skin thickening in 85% and parenchymal distortion in 43%. There was no evidence of distant metastasis on computed tomography of the chest or abdomen. Pathologic examination of breast biopsy specimens showed infiltrating ductal carcinoma in six patients, and one had lobular carcinoma. All patients had prechemotherapy whole-body PET scans that showed diffuse FDG uptake in the breast with superimposed intense foci in the primary tumor. Furthermore, there was skin enhancement in 100%, axillary lymph node in 85%, and skeletal metastases in 14% of the patients, confirmed by bone scintigraphy. Postchemotherapy FDG-PET scans performed in four patients showed response in the primary tumor, axillary lymph nodes, and skeletal metastases. The FDG-PET scan is thus useful for displaying the pattern of FDG breast uptake that reflects the extent of the pathologic involvement in IBC (i.e., diffuse breast involvement and dermal lymphatic spread). It can also detect the presence of lymph node and skeletal metastases, demarcating the extent of the disease locally as well as distally.

Adult↗

Decreased axillary lymph node retrieval in patients after neoadjuvant chemotherapy.

BACKGROUND: The purpose of this study was to assess our clinical impression that fewer lymph nodes are retrieved after level I and II axillary dissection after neoadjuvant chemotherapy and whether there is a positive correlation between the total number of lymph nodes retrieved and the number of diseased lymph nodes. METHODS: Patients included those with stage IIB, IIIA, and IIIB breast cancer of whom 77 had neoadjuvant chemotherapy and 58 had initial surgery only. All had modified radical mastectomy with in continuity level I and II axillary dissection. RESULTS: Patients after neoadjuvant chemotherapy had 14.3 +/- 6.7 lymph nodes detected versus 16.9 +/- 8.8 (mean +/- SD; P <0.057) for those with initial surgery only. The number of positive nodes were 3.7 +/- 4.7 versus 6.6 +/- 8.7 (mean +/- SD; P <0.033) respectively and the number of negative nodes were 10.6 +/- 7.5 versus 10.4 +/- 8 (mean +/- SD; P <0.9). The correlation between the number of positive lymph nodes and the total number of lymph nodes was r = 0.58; P <0.001. CONCLUSIONS: It appears that fewer lymph nodes are retrieved after level I and II axillary dissection after neoadjuvant chemotherapy. The total number of lymph nodes retrieved increases directly with the number of positive lymph nodes in patients not treated with chemotherapy.

Antibiotics, Antineoplastic↗

Emerging role of gammadelta T-cells in health and disease.

The majority of T lymphocytes in the peripheral blood bear the alphabeta type of T-cell receptor (TCR) and less than 5% of circulating T lymphocytes bear the gammadelta type of TCR. The alphabeta and gammadelta T-cells contribute differently to the host immune defense. The immunologic function of gammadelta T-cell in humans is gradually unraveling. Pathologic studies have shown a relatively high proportion of gammadelta T-cells in the gastrointestinal mucosa, skin, and splenic red pulp where they appear to have an important immunologic function against pathogens attempting to enter body through the mucosal surfaces and possibly the skin. More data are emerging about the role of gammadelta T-cells in the course of infectious diseases and in the pathogenesis of autoimmunity. The possible role of these cells in immunologic surveillance against cancer has been inferred from their preferential expansion in certain malignancies. In parallel to the low frequency of these cells in normal lymphocytes, lymphomas bearing gammadelta type of T-cell receptors on cell surface are rare. These include hepatosplenic and non-hepatosplenic (including those involving the skin and those involving nasal cavity and upper aero digestive tract) and the rare non-B-cell cases of lymphomas seen in the immunosuppressed organ transplant patients. The limited available clinical data about gammadelta T-cell lymphomas suggest that these lymphomas tend to have an aggressive course particularly the hepatosplenic form with poor response to multi-agent chemotherapy and short median survival.

Autoimmunity↗

A pilot trial of combination cisplatin, 5-fluorouracil and interferon-alpha in the treatment of advanced esophageal carcinoma.

BACKGROUND/OBJECTIVES: Based on the synergistic effect between cisplatin and 5-fluorouracil (5-FU), and between 5-FU and interferon-alpha, we conducted a trial to assess the response rate and toxicity of the combination of cisplatin, 5-FU and interferon-alpha in patients with advanced esophageal cancer. METHODS: Patients with locally advanced or metastatic squamous cell or adenocarcinoma of the esophagus were eligible. No prior chemotherapy or interferon were allowed. Patients received cisplatin 80 mg/m(2) on day 1, 5-FU 750 mg/m(2)/day by continuous intravenous infusion for 5 days, and interferon-alpha 5 x 10(6) units/m(2)/day by subcutaneous injection on days 1-5 of each cycle. Cycles were repeated every 21 days for a total of 6 cycles. RESULTS: Forty patients were enrolled. Median age was 57.5 years (range 30-70). 33 had squamous carcinoma and 7 adenocarcinoma; 15 were male; the locoregional metastatic ratio was 1:39; median ECOG performance status was 2 (range 1-3). Grade 3-4 toxicities were: leukopenia (9 cases), thrombocytopenia (4), electrolyte imbalance (11), febrile neutropenia (11), vomiting (5), diarrhea (4), and mucositis (11). There were 3 early deaths, most probably related to therapy. Five patients (13%) achieved a complete response and 17 (42%) achieved a partial response, yielding an overall response rate of 55%. Response rates for squamous and adeno histology were 61% and 29%, respectively. Median survival was 6.4 months. CONCLUSION: The combination of cisplatin, 5-FU and interferon-alpha produces a high response rate in advanced squamous cell esophageal carcinoma, but with considerable toxicity. A modified combination of the above agents is presently being evaluated at our institution.

Adenocarcinoma↗

Phase II trial of cisplatin, 5-fluorouracil, and interferon-alpha-2B as first line treatment of advanced urothelial cancer.

Cisplatin based combination chemotherapy remains the mainstay for treatment of advanced urothelial cancer. The combination of 5-fluorouracil and interferon has been found to be effective second line treatment of advanced urothelial cancer. Hence, we tested the combination of cisplatin, 5-fluorouracil and interferon as first line therapy in advanced urothelial cancer. Eligible patients had to have no prior chemotherapy or interferon. Treatment consisted of cisplatin 80 mg/m(2) on day one, followed by 5-fluorouracil 750 mg/m(2) as a daily infusion for 5 days and interferon alpha 2 B 5 MU/m(2) subcutaneously daily on day 1-5 of 5-fluorouracil infusion. Cycles repeated every 21 days. Eighteen patients, of which sixteen were males were enrolled. Median age was 60 years. All patients had transitional-cell carcinoma. The median number of cycles given was 4. Thirteen patients were evaluable for response. Two patients achieved CR and 3 PR for an overall response rate of 28% (95% confidence interval 7% to 49%). Median response duration was 8.3 months. Median survival was 5.5 months. Four patients died secondary to chemotherapy toxicities. Those were GI perforation in one, bronchopneumonia in one, acute renal failure in one and one patient died at home 3 weeks following the third cycle. The above regimen demonstrates excessive toxicity and moderate activity. It cannot be recommended in its present format. Novel anti-cancer agents need to explored.

Acute Kidney Injury↗

18-fluorodeoxyglucose positron emission tomography in cystic carcinoma of the breast.

Cystic infiltrating ductal carcinoma of the breast is uncommon and frequently misdiagnosed because of the predominant cystic presentation clinically. Three premenopausal patients presented with huge cystic breast lesions measuring 10, 19, and 20 cm for 12-, 6-, 10-months duration, respectively. In the first patient, mammography showed a high-density, well-circumscribed huge breast mass, whereas in the other two patients mammography was not possible because of the huge breast size. In all three patients, breast ultrasound showed large cystic lesions suggestive of tumor with central necrosis or bleeding from which a variable amount (270, 1300, 600 ml) of bloody fluid was aspirated, respectively. In the first two patients, cytologic examination of the aspirate showed evidence of malignant cells, whereas the third patient was diagnosed by histologic examination of the cyst wall biopsy. In all three patients, a whole-body positron emission tomography (PET) scan showed intense focal 18-fluorodeoxyglucose (FDG) breast uptake corresponding to the solid component and a ringlike uptake corresponding to the cystic component most likely representing tumor necrosis, hemorrhage, or both. Furthermore, whole-body PET scan was valuable in predicting the response to chemotherapy, characterizing the pelviabdominal mass and detecting the presence of hepatic and spinal metastases in the three patients, respectively. 18-FDG PET scan can help characterize a cystic breast mass by identifying the extent of the cystic and the solid component. It is also useful in staging cystic infiltrating ductal carcinoma by detecting lymph node involvement as well as distant metastases.

Adult↗

Palliative care initiative for the Eastern Mediterranean Region: a proposal.

The Eastern Mediterranean Region (EMR), with 22 countries and about half a billion people, has scarce palliative care services that are far from meeting the needs of the region. The authors of this paper believe that the resources and international influence of the World Health Organization could be combined with the excellent palliative care expertise of King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia to establish a collaborative initiative for promotion of palliative care services in the region. This proposal is based on the major components of professional training, development of regional guidelines, integration of palliative care into health plans and polices, and ensuring availability of essential medications. Investment in developing palliative care in the EMR would be expected to relieve the suffering of hundreds of thousands of patients and families in this part of the world.

Fellowships and Scholarships↗