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  1. Article ; Online: A systematic review of high impact CpG sites and regions for MGMT methylation in glioblastoma [A systematic review of MGMT methylation in GBM].

    Gibson, David / Vo, Anh Huan / Lambing, Hannah / Bhattacharya, Prithanjan / Tahir, Peggy / Chehab, Farid F / Butowski, Nicholas

    BMC neurology

    2024  Volume 24, Issue 1, Page(s) 103

    Abstract: Background: MGMT (O 6 -methylguanine-DNA methyltransferase) promoter methylation is a commonly assessed prognostic marker in glioblastoma (GBM). Epigenetic silencing of the MGMT gene by promoter methylation is associated with greater overall and ... ...

    Abstract Background: MGMT (O 6 -methylguanine-DNA methyltransferase) promoter methylation is a commonly assessed prognostic marker in glioblastoma (GBM). Epigenetic silencing of the MGMT gene by promoter methylation is associated with greater overall and progression free survival with alkylating agent regimens. To date, there is marked heterogeneity in how MGMT promoter methylation is tested and which CpG sites are interrogated.
    Methods: To further elucidate which MGMT promoter CpG sites are of greatest interest, we performed comprehensive searches in PubMed, Web of Science, and Embase and reviewed 2,925 article abstracts. We followed the GRADE scoring system to assess risk of bias and the quality of the studies we included.
    Results: We included articles on adult glioblastoma that examined significant sites or regions within MGMT promoter for the outcomes: overall survival, progression free survival, and/or MGMT expression. We excluded systemic reviews and articles on lower grade glioma. fifteen articles met inclusion criteria with variable overlap in laboratory and statistical methods employed, as well as CpG sites interrogated. Pyrosequencing or BeadChip arrays were the most popular methods utilized, and CpG sites between CpG's 70-90 were most frequently investigated. Overall, there was moderate concordance between the CpG sites that the studies reported to be highly predictive of prognosis. Combinations or means of sites between CpG's 73-89 were associated with improved OS and PFS. Six studies identified CpG sites associated with prognosis that were closer to the transcription start site: CpG's 8, 19, 22, 25, 27, 32,38, and CpG sites 21-37, as well as low methylation level of the enhancer regions.
    Conclusion: The following systematic review details a comprehensive investigation of the current literature and highlights several potential key CpG sites that demonstrate significant association with OS, PFS, and MGMT expression. However, the relationship between extent of MGMT promoter methylation and survival may be non-linear and could be influenced by potential CpG hotspots, the extent of methylation at each CpG site, and MGMT enhancer methylation status. There were several limitations within the studies such as smaller sample sizes, variance between methylation testing methods, and differences in the various statistical methods to test for association to outcome. Further studies of high impact CpG sites in MGMT methylation is warranted.
    MeSH term(s) Humans ; Brain Neoplasms/genetics ; DNA Methylation/genetics ; DNA Modification Methylases/genetics ; DNA Repair Enzymes/genetics ; Glioblastoma/genetics ; Glioma/genetics ; Prognosis ; Tumor Suppressor Proteins/genetics
    Chemical Substances DNA Modification Methylases (EC 2.1.1.-) ; DNA Repair Enzymes (EC 6.5.1.-) ; MGMT protein, human (EC 2.1.1.63) ; Tumor Suppressor Proteins
    Language English
    Publishing date 2024-03-23
    Publishing country England
    Document type Systematic Review ; Journal Article
    ZDB-ID 2041347-6
    ISSN 1471-2377 ; 1471-2377
    ISSN (online) 1471-2377
    ISSN 1471-2377
    DOI 10.1186/s12883-024-03605-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: 20 years of leptin: leptin and reproduction: past milestones, present undertakings, and future endeavors.

    Chehab, Farid F

    The Journal of endocrinology

    2014  Volume 223, Issue 1, Page(s) T37–48

    Abstract: The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake ... ...

    Abstract The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake prompted the dissection of neuroendocrine mechanisms involving leptin in the metabolic control of reproduction. The absence of leptin receptors on GnRH neurons incited a search for intermediary neurons situated between leptin-responsive and GnRH neurons. This review addresses the most significant findings that have furthered our understanding of recent progress in this new field. The role of leptin in puberty was impacted by the discovery of neurons that co-express kisspeptin, neurokinin B, and dynorphin and these could act as leptin intermediates. Furthermore, the identification of first-order leptin-responsive neurons in the premammilary ventral nucleus and other brain regions opens new avenues to explore their relationship to GnRH neurons. Central to these advances is the unveiling that agouti-related protein/neuropeptide Y neurons project onto GnRH and kisspeptin neurons, allowing for a crosstalk between food intake and reproduction. Finally, while puberty is a state of leptin sensitivity, mid-gestation represents a state of leptin resistance aimed at building energy stores to sustain pregnancy and lactation. The mechanisms underlying leptin resistance in pregnancy have lagged; however, the establishment of this natural state is significant. Reproduction and energy balance are tightly controlled and backed up by redundant mechanisms that are critical for the survival of our species. It will be the goal of the following decade to shed new light on these complex and essential pathways.
    MeSH term(s) Animals ; Female ; Gonadotropin-Releasing Hormone/metabolism ; Humans ; Kisspeptins/metabolism ; Leptin/metabolism ; Leptin/physiology ; Models, Biological ; Neurons/metabolism ; Reproduction/physiology ; Sexual Maturation/physiology
    Chemical Substances Kisspeptins ; Leptin ; Gonadotropin-Releasing Hormone (33515-09-2)
    Language English
    Publishing date 2014-08-12
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 3028-4
    ISSN 1479-6805 ; 0022-0795
    ISSN (online) 1479-6805
    ISSN 0022-0795
    DOI 10.1530/JOE-14-0413
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Obesity and lipodystrophy--where do the circles intersect?

    Chehab, Farid F

    Endocrinology

    2008  Volume 149, Issue 3, Page(s) 925–934

    Abstract: Adipose tissue is unique in that it can undergo significant hypertrophy and atrophy, resulting in wide ranges of obesities and lipodystrophies. At the base of this elasticity is the lipid-filled adipocyte, which can either overfill by storing large ... ...

    Abstract Adipose tissue is unique in that it can undergo significant hypertrophy and atrophy, resulting in wide ranges of obesities and lipodystrophies. At the base of this elasticity is the lipid-filled adipocyte, which can either overfill by storing large amounts of triglycerides or shrink to a tiny cell by depleting its lipids and as such is remarkable in sustaining insults. As a major energy reservoir, the adipocyte may hold considerable calories necessary for survival and reproduction, two functions that are essential for the survival of the species. This review will summarize some of the recent studies that have advanced our understanding of the central and peripheral mechanisms that are initiated by adipocyte-secreted factors such as leptin, adiponectin, resistin, and retinol-binding protein 4. The intersection of obesity and lipodystrophy results in insulin resistance, which may be unlocked by elucidating the roles of these factors in pathways that control insulin sensitivity and glucose uptake.
    MeSH term(s) Adipose Tissue/physiopathology ; Animals ; Disease Models, Animal ; Energy Metabolism/physiology ; Humans ; Insulin Resistance/physiology ; Lipodystrophy/physiopathology ; Mice ; Obesity/physiopathology
    Language English
    Publishing date 2008-01-17
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 427856-2
    ISSN 1945-7170 ; 0013-7227
    ISSN (online) 1945-7170
    ISSN 0013-7227
    DOI 10.1210/en.2007-1355
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Parietal mass caused by a fish bone: case report.

    Erguibi, Driss / Kamal, Khadija / Eddaoudi, Yassine / Hajri, Amal / Boufettal, Rachid / Rifki El Jai, Saad / Chehab, Farid

    Annals of medicine and surgery (2012)

    2023  Volume 85, Issue 2, Page(s) 299–301

    Abstract: It is a great challenge to distinguish the parietal inflammation, centered on the foreign body that pierced the digestive tract and remained in the wall before surgery, because of its atypical clinical nature. Ingestion of foreign bodies is not uncommon. ...

    Abstract It is a great challenge to distinguish the parietal inflammation, centered on the foreign body that pierced the digestive tract and remained in the wall before surgery, because of its atypical clinical nature. Ingestion of foreign bodies is not uncommon. Fish bones are particularly notorious culprits; however, most will pass through the gastrointestinal tract uneventfully.
    Patients and methods: The authors report a case of a patient who presented with periumbilical abdominal pain and a computed tomography (CT) scan that revealed the presence of periumbilical fat infiltration on a foreign body admitted on the Department of Digestive Cancer Surgery and Liver Transplantation, Casablanca, Morocco. An exploratory laparotomy revealed a parietal mass centered by a fish bone.
    Results: Accidental ingestion of foreign bodies is common in clinical practice. However, perforation of the intestine by a foreign body is less common because the majority of foreign bodies pass without incident into the feces and only 1% of them (the sharpest and most elongated objects) will perforate the gastrointestinal tract, usually at the level of the ileum.CT, especially multidetector CT, is considered the method of choice for preoperative diagnoses of ingested foreign bodies and their complications due to its high-quality multiplanar capabilities and high resolution.Foreign body ingestion usually goes unnoticed, but the complications of this incident can be severe.
    Conclusion: This case report highlights the fact that intestinal perforation caused by an ingested foreign body is a difficult diagnosis that should always be suspected in an attack of abdominal pain. Frequently, the clinical diagnosis is difficult, and recourse to imaging is sometimes necessary. Most of the time, the treatment is only surgical.
    Language English
    Publishing date 2023-02-17
    Publishing country England
    Document type Journal Article
    ZDB-ID 2745440-X
    ISSN 2049-0801
    ISSN 2049-0801
    DOI 10.1097/MS9.0000000000000241
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: PAX5, NOTCH3, CBFB, and ACD drive an activated RAS pathway and monosomy 7 to B-ALL and AML in donor cell leukemia.

    Assi, Rita / Mahfouz, Rami / Owen, Renius / Gunthorpe, Martha / Chehab, Farid F / Bazarbachi, Ali

    Bone marrow transplantation

    2018  Volume 54, Issue 7, Page(s) 1124–1128

    MeSH term(s) Adult ; Chromosome Deletion ; Chromosomes, Human, Pair 7 ; Core Binding Factor beta Subunit/genetics ; Core Binding Factor beta Subunit/metabolism ; Female ; Humans ; Leukemia, Myeloid, Acute/genetics ; Leukemia, Myeloid, Acute/metabolism ; Male ; Middle Aged ; PAX5 Transcription Factor/genetics ; PAX5 Transcription Factor/metabolism ; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics ; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/metabolism ; Proto-Oncogene Proteins p21(ras)/genetics ; Proto-Oncogene Proteins p21(ras)/metabolism ; Receptor, Notch3 ; Signal Transduction ; Telomere-Binding Proteins/genetics ; Telomere-Binding Proteins/metabolism
    Chemical Substances ACD protein, human ; CBFB protein, human ; Core Binding Factor beta Subunit ; NOTCH3 protein, human ; PAX5 Transcription Factor ; PAX5 protein, human ; Receptor, Notch3 ; Telomere-Binding Proteins ; Proto-Oncogene Proteins p21(ras) (EC 3.6.5.2)
    Language English
    Publishing date 2018-12-10
    Publishing country England
    Document type Clinical Trial ; Letter
    ZDB-ID 632854-4
    ISSN 1476-5365 ; 0268-3369 ; 0951-3078
    ISSN (online) 1476-5365
    ISSN 0268-3369 ; 0951-3078
    DOI 10.1038/s41409-018-0419-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Helicobacter pylori

    Rihane, Fatima Ezzahra / Erguibi, Driss / Elyamine, Othmane / Abumsimir, Berjas / Ennaji, Moulay Mustapha / Chehab, Farid

    Annals of medicine and surgery (2012)

    2021  Volume 68, Page(s) 102651

    Abstract: Background: Gastric cancer (GC) is one of the leading causes of morbidity and mortality worldwide. The onset and progression of gastric cancer are attributed to numerous triggers, these triggers may be infection of the gastric epithelium by : Methods!# ...

    Abstract Background: Gastric cancer (GC) is one of the leading causes of morbidity and mortality worldwide. The onset and progression of gastric cancer are attributed to numerous triggers, these triggers may be infection of the gastric epithelium by
    Methods: In this study, 100 gastric tissue samples from patients with gastric cancer were examined for detection of
    Results: Results revealed an individual Epstein-Barr virus (EBV) infection observed in (40 %) of gastric carcinoma cases. Furthermore, the frequency of EBV infection was significantly different with intestinal and diffuse gastric cancer types [15 % vs. 85 %; <0.05]. The prevalence of individual
    Conclusion: Thus understanding the status of co-infection could clarify the process of gastric carcinogenesis, and application of this knowledge for clinical purposes could facilitate diagnosis, risk management, and prevention.
    Language English
    Publishing date 2021-07-31
    Publishing country England
    Document type Journal Article
    ZDB-ID 2745440-X
    ISSN 2049-0801
    ISSN 2049-0801
    DOI 10.1016/j.amsu.2021.102651
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Solid pseudopapillary neoplasm of the head of the pancreas: A case report.

    Erguibi, Driss / El Berni, Yassine / Moufakkir, Aziz / Boufettal, Rachid / Rifki Jai Saad / Chehab, Farid

    Annals of medicine and surgery (2012)

    2021  Volume 69, Page(s) 102708

    Abstract: ... This is an interesting case report of a rare tumor, in so far as without any adjuvant chemotherapy ...

    Abstract Introduction: and importance: Solid pseudopapillary tumor of the pancreas (SPN) or Frantz's tumor is a rare tumor of low malignant potential common in young women. The aim of this paper is to present and discuss a case of a solid pseudopapillary tumor of the pancreas occurring in a 19-year-old female.
    Case presentation: A 19-year-old girl presented to our department with epigastric pain for two months, she had no clinical findings on physical examination. Abdominal Computed tomography scan (CT scan) showed the presence of a well-defined tumor arising from the pancreatic head measuring 9,1 × 8.1 × 8.5 cm, heterogeneous and with solid and necrosis components. The patient was subjected to surgery and histopathological examination confirmed the diagnosis of a pseudopapillary tumor of the pancreas.
    Clinical discussion: This is an interesting case report of a rare tumor, in so far as without any adjuvant chemotherapy Prognosis of the tumor is better than other pancreatic tumors. surgical resection seems to be the best strategy in the management of SPT.
    Conclusion: Close follow up is necessary for early detection of the recurrence and metastasis.
    Language English
    Publishing date 2021-08-10
    Publishing country England
    Document type Case Reports
    ZDB-ID 2745440-X
    ISSN 2049-0801
    ISSN 2049-0801
    DOI 10.1016/j.amsu.2021.102708
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: RETRACTED ARTICLE: Upregulation of miR-21 Expression in Gastric Cancer and Its Clinicopathological Feature Association.

    Rihane, Fatima Ezzahra / Erguibi, Driss / Lamsisi, Maryame / Chehab, Farid / Ennaji, Moulay Mustapha

    Journal of gastrointestinal cancer

    2021  Volume 53, Issue 1, Page(s) 236

    Language English
    Publishing date 2021-08-19
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2452514-5
    ISSN 1941-6636 ; 1559-0739 ; 1941-6628 ; 1537-3649
    ISSN (online) 1941-6636 ; 1559-0739
    ISSN 1941-6628 ; 1537-3649
    DOI 10.1007/s12029-021-00691-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Postsurgical Diagnosis of an Unusual Case of Primary Hepatic Lymphoma Presenting as Liver Abscess with an Uncommon Complication: A Hepatogastric Fistula.

    Yaka, Mbarek / Chehab, Farid / Allaoui, Mohmed / Ait Ali, Abdelmonaim / Zentar, Aziz

    Case reports in hematology

    2021  Volume 2021, Page(s) 6647558

    Abstract: Primary hepatic lymphoma (PHL) is a very rare malignancy and constitutes 0.016% of all cases of non-Hodgkin's lymphoma and 0.4% of extranodal non-Hodgkin's lymphoma. We describe a rare case of primary hepatic lymphoma presenting as liver abscess which ... ...

    Abstract Primary hepatic lymphoma (PHL) is a very rare malignancy and constitutes 0.016% of all cases of non-Hodgkin's lymphoma and 0.4% of extranodal non-Hodgkin's lymphoma. We describe a rare case of primary hepatic lymphoma presenting as liver abscess which was complicated with the development of a hepatogastric fistula. A 58-year-old man presented with clinical signs of sepsis, high-grade fever, right upper abdominal pain, and weight loss which had progressed in the past 8 months. Noncontrast abdominal computed tomography (CT) revealed a heterogeneously hypodense lesion in the left lobe of the liver with multiple air foci within, which are seen to extend into the body of the stomach. The patient was initially misdiagnosed as a case of rupture of liver abscess into the stomach. Postoperative liver biopsy examination confirmed a diagnosis of diffuse large B-cell lymphoma. Systemic staging revealed no evidence of nodal or bone marrow involvement, so PHL was diagnosed. Chemotherapy was initiated, but discontinued due to the patient's general condition. Finally, the patient succumbed to neutropenic fever following chemotherapy. Here, we present the exceptional case of a primary hepatic lymphoma with an unusual complication, a hepatogastric fistula, and try through the existing literature to show the difficulties involved in diagnosis and treatment.
    Language English
    Publishing date 2021-02-24
    Publishing country United States
    Document type Case Reports
    ZDB-ID 2627639-2
    ISSN 2090-6579 ; 2090-6560
    ISSN (online) 2090-6579
    ISSN 2090-6560
    DOI 10.1155/2021/6647558
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Molecular assessment of pretransplant chemotherapy in the treatment of juvenile myelomonocytic leukemia.

    Hecht, Anna / Meyer, Julia / Chehab, Farid F / White, Kristie L / Magruder, Kevin / Dvorak, Christopher C / Loh, Mignon L / Stieglitz, Elliot

    Pediatric blood & cancer

    2019  Volume 66, Issue 11, Page(s) e27948

    Abstract: Background: Despite the intensity of hematopoietic stem cell transplantation (HCT), relapse remains the most common cause of death in juvenile myelomonocytic leukemia (JMML). In contrast to other leukemias where therapy is used to reduce leukemic burden ...

    Abstract Background: Despite the intensity of hematopoietic stem cell transplantation (HCT), relapse remains the most common cause of death in juvenile myelomonocytic leukemia (JMML). In contrast to other leukemias where therapy is used to reduce leukemic burden prior to transplant, many patients with JMML proceed directly to HCT with active disease. The objective of this study was to elucidate whether pre-HCT therapy has an effect on the molecular burden of disease and how this affects outcome post-HCT.
    Procedure: Twenty-one patients with JMML who received pre-HCT therapy and were transplanted at UCSF were analyzed in this study. The mutant allele frequency of the driver mutation was assessed before and after pre-HCT therapy, using custom amplicon next-generation sequencing.
    Results: Of the 21 patients, seven patients (33%) responded to therapy with a significant reduction in their mutant allele frequency and were classified as molecular responders. Six of these patients received moderate-intensity chemotherapy, one patient received only azacitidine. The 5-year progression-free survival after HCT of molecular responders was 100% versus 61% for nonresponders (P = .12). Survival of molecular nonresponders was not improved by use of high-intensity conditioning, but patients were salvaged if they experienced severe graft versus host disease. There were no baseline clinical characteristics that were associated with response to pre-HCT therapy.
    Conclusions: Despite the myelodysplastic nature of JMML, patients treated with pre-HCT therapy can achieve molecular remissions. These patients experienced a trend toward improved outcomes post-HCT. Importantly, molecular testing can be helpful to distinguish between responders and nonresponders and should become an integral part of clinical care.
    MeSH term(s) Antimetabolites, Antineoplastic/administration & dosage ; Antimetabolites, Antineoplastic/therapeutic use ; Antineoplastic Combined Chemotherapy Protocols/administration & dosage ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; Child ; Child, Preschool ; Combined Modality Therapy ; DNA, Neoplasm/blood ; Drug Evaluation ; Drug Monitoring ; Female ; Follow-Up Studies ; Genes, Neoplasm ; Graft vs Host Disease/etiology ; Graft vs Host Disease/therapy ; Hematopoietic Stem Cell Transplantation ; Humans ; Infant ; Leukemia, Myelomonocytic, Juvenile/blood ; Leukemia, Myelomonocytic, Juvenile/drug therapy ; Leukemia, Myelomonocytic, Juvenile/genetics ; Leukemia, Myelomonocytic, Juvenile/therapy ; Male ; Neoadjuvant Therapy ; Neoplasm Proteins/genetics ; Progression-Free Survival ; Recurrence ; Retrospective Studies ; Sequence Analysis, DNA ; Splenectomy ; Transplantation Conditioning ; Tumor Burden/drug effects
    Chemical Substances Antimetabolites, Antineoplastic ; DNA, Neoplasm ; Neoplasm Proteins
    Language English
    Publishing date 2019-07-26
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2131448-2
    ISSN 1545-5017 ; 1545-5009
    ISSN (online) 1545-5017
    ISSN 1545-5009
    DOI 10.1002/pbc.27948
    Database MEDical Literature Analysis and Retrieval System OnLINE

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