Arafat Tfayli

Tamoxifen metabolism predicts drug concentrations and outcome in premenopausal patients with early breast cancer

Tamoxifen is the standard-of-care treatment for estrogen receptor-positive premenopausal breast cancer. We examined tamoxifen metabolism via blood metabolite concentrations and germline variations of CYP3A5, CYP2C9, CYP2C19 and CYP2D6 in 587 premenopausal patients (Asians, Middle Eastern Arabs, Caucasian-UK; median age 39 years) and clinical outcome in 306 patients. N-desmethyltamoxifen (DM-Tam)/(Z)-endoxifen and CYP2D6 phenotype significantly correlated across ethnicities (R2: 53%, P<10−77). CYP2C19 and CYP2C9 correlated with norendoxifen and (Z)-4-hydroxytamoxifen concentrations, respectively (P<0.001). DM-Tam was influenced by body mass index (P<0.001). Improved distant relapse-free survival (DRFS) was associated with decreasing DM-Tam/(Z)-endoxifen (P=0.036) and increasing CYP2D6 activity score (hazard ratio (HR)=0.62; 95% confidence interval (CI), 0.43–0.91; P=0.013). Low (<14 nM) compared with high (>35 nM) endoxifen concentrations were associated with shorter DRFS (univariate P=0.03; multivariate HR=1.94; 95% CI, 1.04–4.14; P=0.064). Our data indicate that endoxifen formation in premenopausal women depends on CYP2D6 irrespective of ethnicity. Low endoxifen concentration/formation and decreased CYP2D6 activity predict shorter DRFS.

Breast Cancer in Low- and Middle-Income Countries: An Emerging and Challenging Epidemic

Breast cancer is a major health care problem that affects more than one million women yearly. While it is traditionally thought of as a disease of the industrialized world, around 45% of breast cancer cases and 55% of breast cancer deaths occur in low and middle income countries. Managing breast cancer in low income countries poses a different set of challenges including access to screening, stage at presentation, adequacy of management and availability of therapeutic interventions. In this paper, we will review the challenges faced in the management of breast cancer in low and middle income countries.

Expression, prognostic and predictive impact of VEGF and bFGF in non-small cell lung cancer.

Despite major advances in cancer therapeutics, the prognosis for lung cancer patients is still poor and the median survival for patients presenting with advanced non-small cell lung cancer (NSCLC) is only 8-10 months. Angiogenesis is an important biological process and a relatively early event during lung cancer pathogenesis. Anti-angiogenic agents are used in treating patients with NSCLC, and their molecular biomarkers are also being assessed to predict response. A better understanding of the biology of angiogenesis in NSCLC may reveal new targets for treating this malignancy. In this article, we review the expression and prognostic impact of the angiogenic growth factors, vascular endothelial growth factor and basic fibroblast growth factor, in NSCLC.

Treatment of metastatic breast cancer: state-of-the-art, subtypes and perspectives.

Current treatment of metastatic breast cancer (MBC) aims at achieving meaningful clinical responses, improved quality of life, long-term remissions, prolonged survival, and dares to hope for a cure in a small percentage of cases. This article will discuss both consensus and controversies in the management of MBC in the context of the new evolving breast cancer molecular classification. Hormonal therapy remains the mainstay of management of MBC Luminal A and B. Data is emerging on management of ErbB2-positive HR-positive MBC by combining hormonal manipulation and targeted anti-ErbB2 therapy and has recently received regulatory approval in Europe and USA. The optimal use and duration of single agent or combination chemotherapy is discussed. Data and controversies surrounding the use of newer agents such as nab-paclitaxel, ixabepilone, eribulin, and PARP inhibitors as well as trastuzumab is reviewed. Better understanding of pathophysiology has paved the way for the introduction of newer anti-ErbB2 agents such as lapatinib, pertuzumab, T-DM1 and neratinib. Controversies regarding bevacizumab and anti-angiogenesis are discussed. Bisphosphonates have significantly reduced skeletal related events and made significant improvements in the quality of life of patients with MBC. Newer anti-RANK Ligand antibodies show promising results. Significant advances in the understanding of molecular biology of breast cancer have been made and should lead to an improvement in the outcome of MBC. More possibilities of cure can become an attainable goal in the near future.

miRNA as Potential Biomarkers of Breast Cancer in the Lebanese Population and in Young Women: A Pilot Study

Relative to western populations, the percentage of women diagnosed with breast cancer at a young age in Lebanon is high. While the younger age of the Lebanese population compared to the West certainly contributes to this difference, potential genetic, reproductive and/or biological factors likely play an important role. The objective of this study is to investigate the contribution of miRNAs in this setting through the analysis of the expression of five reported dysregulated miRNAs, miR-148b, miR-10b, miR-21, miR-221, and miR-155 in 20 normal and 57 cancerous breast tissues from Lebanese breast cancer patients. After finding their relative expression by quantitative reverse transcription real time PCR, the results were analyzed with respect to the patients’ clinical and histopathology presentations. Compared to normal breast tissues, significant upregulation of miR-155, miR-21 and miR-148b, notable downregulation of miR-10b and non-significant expression of miR-221 were observed in tumor tissues. Moreover, miR-10b was significantly underexpressed in estrogen/progesterone receptor (ER/PR) negative tumors relative to ER/PR positive tumor tissues. miR-155 was also significantly overexpressed in postmenopausal patients and in those of age at diagnosis greater than 40 years old as well as in PR negative or in human epidermal growth factor 2 (Her2) positive tissues. This study is the first one to report miRNA expression patterns in Lebanese breast cancer patients. We found that differential miRNA expression in breast cancer could be variable between Lebanese and Western populations. miR-10b was positively correlated with the ER and PR status and miR-155 could be a noteworthy biomarker for the menopausal state, age at diagnosis, PR and Her2 status. Hence, miRNA can be used as biomarkers for early breast cancer detection.

Genetic polymorphisms of CYP2E1, GST, and NAT2 enzymes are not associated with risk of breast cancer in a sample of Lebanese women.

Changes in the activity of drug metabolizing enzymes (DMEs) are potentially associated with cancer risk. This relationship is attributed to their involvement in the bioactivation of multiple procarcinogens or the metabolism of multiple substrates including an array of xenobiotics and environmental carcinogens. 326 Lebanese women of whom 99 were cancer free (controls) and 227 were diagnosed with breast cancer (cases) were included. Blood for DNA was collected and medical charts were reviewed. Three genotyping methods were employed including: (1) restriction fragment length polymorphism (RFLP) for CYP2E1*5B, CYP2E1*6, NAT2*5 and NAT2*6; (2) gel electrophoresis for GSTM1 and GSTT1; and (3) real-time PCR for GSTP1 Ile/Val polymorphism. We analyzed the relationship between genetic susceptibilities in selected xenobiotic metabolizing genes and breast cancer risk. Allele frequencies were fairly similar to previously reported values from neighboring populations with relevant migration routes. There were no statistically significant differences in the distribution of variant carcinogen metabolizing genes between cases and controls even after adjusting for age at diagnosis, menopausal status, smoking, and alcohol intake. Despite its limitations, this is the first study that assesses the role of genetic polymorphisms in DMEs with breast cancer in a sample of Lebanese women. Further studies are needed to determine the genetic predisposition and gene-environment interactions of breast cancer in this population.

Pharmacogenomics Variation in Drug Metabolizing Enzymes and Transporters in Relation to Docetaxel Toxicity in Lebanese Breast Cancer Patients: Paving the Way for OMICs in Low and Middle Income Countries

We investigated the association of genetic polymorphisms in drug metabolizing enzymes (DMEs) and transporters in patients with docetaxel-induced febrile neutropenia, by a new high-throughput DMEs and transporters (DMETPlus) microarray platform, characterizing 1936 single nucleotide polymorphisms (SNPs) in 225 genes. We recruited 100 Lebanese breast cancer patients from a consecutive cohort of 277 patients who received docetaxel either alone, or in combination with trastuzumab. Out of 100 patients, 18 had developed febrile neutropenia (cases). They were age- and treatment- matched with 18 patients who did not develop febrile neutropenia on docetaxel (controls). We found that 12 SNPs in seven genes (ABCC6, ABCG1, ABCG2, CYP1A2, CYP2D6, FMO2, and FMO3) were significantly associated with febrile neutropenia after docetaxel treatment. Many of these SNPs have not been previously reported to be associated with toxicity due to docetaxel treatment. Interestingly, one SNP in the FMO3 gene (rs909530) was significantly associated with three clinical endpoints: febrile neutropenia, reduced absolute neutrophil count, and hemoglobin reduction. To the best of our knowledge, this is the first study that evaluated the effect of a large array of nearly 2000 polymorphisms in DMEs and transporters on docetaxel toxicity in breast cancer patients, and in a previously understudied population. Additionally, it attests to the feasibility of genomics research in low- and middle-income countries (LMICs). In light of the current global epidemic of noncommunicable diseases (NCDs) such as breast cancer impacting LMICs, we suggest pharmacogenomics is considered as an integral part of the global health research agenda for NCDs and personalized therapeutics.

Gastric Antral Vascular Ectasia in a Patient with GIST after Treatment with Imatinib: Case Report and Literature Review

Imatinib mesylate is a receptor kinase inhibitor approved by the Food and Drug Administration for the treatment of malignant metastatic and/or unresectable gastrointestinal stromal tumors and chronic myelogenous leukemia. Although imatinib is generally well tolerated, certain adverse drug reactions are common. These include gastrointestinal side-effects such as diarrhea, nausea and vomiting, as well as hematological side-effects and other miscellaneous side-effects such as fatigue, edema, dermatitis and dyspnea. We present a previously unreported adverse effect of imatinib, gastric antral vascular ectasia, in a 74-year-old woman with gastrointestinal stromal tumor in remission treated with adjuvant imatinib. Endoscopy performed prior to starting imatinib showed normal gastric mucosa, but 8 months after starting imatinib showed diffuse gastric inflammation. Repeat endoscopy 1 month after discontinuing imatinib showed significant improvement in gastric inflammation.

BRCA1 and BRCA2 Mutations in Ethnic Lebanese Arab Women With High Hereditary Risk Breast Cancer

PURPOSE Breast cancer is the most common malignancy among women in Lebanon and in Arab countries, with 50% of cases presenting before the age of 50 years. METHODS Between 2009 and 2012, 250 Lebanese women with breast cancer who were considered to be at high risk of carrying BRCA1 or BRCA2 mutations because of presentation at young age and/or positive family history (FH) of breast or ovarian cancer were recruited. Clinical data were analyzed statistically. Coding exons and intron-exon boundaries of BRCA1 and BRCA2 were sequenced from peripheral blood DNA. All patients were tested for BRCA1 rearrangements using multiplex ligation-dependent probe amplification (MLPA). BRCA2 MLPA was done in selected cases. RESULTS Overall, 14 of 250 patients (5.6%) carried a deleterious BRCA mutation (7 BRCA1, 7 BRCA2) and 31 (12.4%) carried a variant of uncertain significance. Eight of 74 patients (10.8%) aged ≤40 years with positive FH and only 1 of 74 patients (1.4%) aged ≤40 years without FH had a mutated BRCA. Four of 75 patients (5.3%) aged 41-50 years with FH had a deleterious mutation. Only 1 of 27 patients aged >50 years at diagnosis had a BRCA mutation. All seven patients with BRCA1 mutations had grade 3 infiltrating ductal carcinoma and triple-negative breast cancer. Nine BRCA1 and 17 BRCA2 common haplotypes were observed. CONCLUSION Prevalence of deleterious BRCA mutations is lower than expected and does not support the hypothesis that BRCA mutations alone cause the observed high percentage of breast cancer in young women of Lebanese and Arab descent. Studies to search for other genetic mutations are recommended.

Physical symptom profile for adult cancer inpatients at a Lebanese cancer unit

BACKGROUND Hospital-based palliative care programs in Lebanon are nonexistent in a structured form. One of obstacles is the lack of knowledge about symptom prevalence and burden of cancer patients in Lebanon. METHODS This is a cross-sectional observational study where 100 adult cancer patients admitted to the American University of Beirut Medical Center inpatient unit completed a survey to assess 20 physical symptoms according the National Cancer Institutes Common Terminology Criteria for Adverse Events 4.0 (NCI-CTCAE 4.0) guidelines. RESULTS Hematologic, gastrointestinal, breast, and lung cancers were the most common. Mean age was 51.5 years; 51% were female. 74% of patients with solid tumors had metastatic disease. Treatment approaches were palliative chemotherapy, followed by curative chemotherapy and best supportive care. The most common symptoms were fatigue, appetite loss, nausea, and pain; most distressing were nausea, pain, and fatigue. Nausea and vomiting were more prevalent among females than males. Females reported more severe vomiting than males, but males had more intense pain. Overall symptom burden difference was statistically significant across age groups, with the 51-60 year group having the most symptoms, but not among different genders. Difference was significant among different treatment intents, with the best supportive care group having most symptoms. CONCLUSION Fatigue should be better addressed as a legitimate symptom. Subgroup differences must be considered when managing gastrointestinal symptoms. Pain should be more effectively managed, and vulnerable subgroups such as the 51-60 year age group and those on best supportive care should receive special consideration.