Displaying publications 1 - 20 of 24 in total

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  1. Kiew LV, Cheong SK, Sidik K, Chung LY
    Int J Pharm, 2010 May 31;391(1-2):212-20.
    PMID: 20214970 DOI: 10.1016/j.ijpharm.2010.03.010
    To enhance the stability of the anticancer drug gemcitabine (2'-deoxy-2',2'-difluorocytidine), it was conjugated to poly-l-glutamic acid (PG-H) via a carbodiimide reaction. The synthesised poly-l-glutamic acid-gemcitabine (PG-G) was purified and characterised by using SDS-PAGE to estimate its molecular weight, HPLC to determine its purity and degree of drug loading, and NMR to elucidate the structure. In vitro aqueous hydrolytic studies showed that the gemcitabine release from the polymeric drug conjugate was pH dependent, and that the conjugation to PG-H improved its stability in human plasma. The release of the bound gemcitabine from PG-G in plasma was mediated by a hydrolytic process. It began with a lag phase, followed by linear release between 12 and 48h, and reached equilibrium at 72h with 51% of the gemcitabine released. In vitro cytotoxicity studies using MCF-7 and MDA-MB-231 human mammary cancer cells, as well as human dermal fibroblasts (HDF), showed that PG-G displayed a lower dose dependent cytotoxic effect with respect to the parent drug gemcitabine. On the other hand, in 4T1 mouse mammary tumour cells, PG-G and gemcitabine showed similar toxicities. Gemcitabine was more than likely released hydrolytically from PG-G and taken up by MCF-7, MDA-MB-231 and HDF, whereas both released gemcitabine and PG-G were taken up by 4T1 to mediate the observed cytotoxicities. The improved stability and extended sustained release profile may render PG-G a potential anticancer prodrug.
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/analogs & derivatives*; Deoxycytidine/blood; Deoxycytidine/chemical synthesis; Deoxycytidine/pharmacokinetics; Deoxycytidine/pharmacology; Deoxycytidine/chemistry
  2. Affandi AM, Blumetti TP, Wells J, Hertzberg M, Fernandez-Peñas P
    Australas J Dermatol, 2015 Nov;56(4):294-7.
    PMID: 25496219 DOI: 10.1111/ajd.12270
    Treatment options for advanced stage cutaneous T-cell lymphoma (CTCL) are limited by the their efficacy and side-effects profile. Gemcitabine, a pyrimidine analogue, has been reported to be efficacious in CTCL. Most of the studies published used gemcitabine as a single agent in treating advanced CTCL. Our small case series demonstrated that a combination of gemcitabine and vinorelbine induced partial remission in all four patients with refractory or advanced CTCL, although the effects were not sustained for a long duration (2-6 months). Two patients had neutropenia and one had acute hepatitis, requiring discontinuation of treatment.
    Matched MeSH terms: Deoxycytidine
  3. Kamal NAMA, Abdulmalek E, Fakurazi S, Cordova KE, Abdul Rahman MB
    Dalton Trans, 2021 Feb 23;50(7):2375-2386.
    PMID: 33555001 DOI: 10.1039/d1dt00116g
    Chemotherapeutic agents used in treating certain cancer types operate in a non-selective manner tending to accumulate in normal, healthy tissue when high doses are used. To mitigate the toxicity effect resulting from this, there is an urgent need to develop active nano delivery systems capable of regulating optimal doses specifically to cancer cells without harming adjacent normal cells. Herein, we report a versatile nanoparticle - zeolitic imidazolate framework-8 (nZIF-8) - that is loaded with a chemotherapeutic agent (gemcitabine; GEM) and surface-functionalized with an autonomous homing system (Arg-Gly-Asp peptide ligand; RGD) via a straightforward, one-pot solvothermal reaction. Successful functionalization of the surface of nZIF-8 loaded GEM (GEM⊂nZIF-8) with RGD was proven by spectroscopic and electron microscopy techniques. This surface-functionalized nanoparticle (GEM⊂RGD@nZIF-8) exhibited enhanced uptake in human lung cancer cells (A549), compared with non-functionalized GEM⊂nZIF-8. The GEM⊂RGD@nZIF-8, experienced not only efficient uptake within A549, but also induced obvious cytotoxicity (75% at a concentration of 10 μg mL-1) and apoptosis (62%) after 48 h treatment when compared to the nanoparticle absent of the RGD homing system (GEM⊂nZIF-8). Most importantly, this surface-functionalized nanoparticle was more selective towards lung cancer cells (A549) than normal human lung fibroblast cells (MRC-5) with a selectivity index (SI) of 3.98. This work demonstrates a new one-pot strategy for realizing a surface-functionalized zeolitic imidazolate framework that actively targets cancer cells via an autonomous homing peptide system to deliver a chemotherapeutic payload effectively.
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/analogs & derivatives*; Deoxycytidine/chemistry
  4. Mozar FS, Chowdhury EH
    Curr Drug Deliv, 2015;12(3):333-41.
    PMID: 25600981
    Substantial amount of research has been done in recent decades for the development of nanoparticle systems to selectively deliver drugs to cancer cells for concurrently enhancing and reducing anti-cancer and off-target effects, respectively. pH-sensitive carbonate apatite (CA) was originally developed for efficient and targeted delivery of DNA, siRNA and proteins to various cancer cell lines. Recently, the CA particles were employed to deliver anti-cancer drugs, cyclophosphamide, doxorubicin and methotrexate to cancer cells. Here, we report on the fabrication and characterization of gemcitabine- loaded CA particles, followed by the evaluation of their roles in enhancement of cytotoxicity in two human and one murine breast cancer cell lines. HPLC was performed to measure binding efficiency of the drug to the apatite particles whereas particle size and zeta potential were evaluated to characterize drug/apatite complex. Depending on the initial doses of the drug, its bind binding affinity towards the particles varied from 3.85% to 4.45%. The particle size was found to surprisingly decrease with an increase of the initial drug concentration. In vitro chemosensitivity assay revealed that apatite/drug nanoparticle complexes presented significantly higher cytotoxicity to breast cancer cells compared to free drugs, which could be correlated with the enhanced cellular uptake of the small size drug-loaded particles through endocytosis compared to the passive diffusion of the free drug.
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/analogs & derivatives*; Deoxycytidine/pharmacology
  5. Yunus U, Zulfiqar MA, Ajmal M, Bhatti MH, Chaudhry GE, Muhammad TST, et al.
    Biomed Mater, 2020 09 26;15(6):065004.
    PMID: 32442994 DOI: 10.1088/1748-605X/ab95e1
    Gemcitabine (GEM) is used to treat various cancers such as breast, pancreatic, non-small lung, ovarian, bladder, and cervical cancers. GEM, however, has the problem of non-selectivity. Water-soluble, fluorescent, and mono-dispersed carbon dots (CDs) were fabricated by ultrasonication of sucrose. The CDs were further conjugated with GEM through amide linkage. The physical and morphological properties of these carbon dot-gemcitabine (CD-GEM) conjugates were determined using different analytical techniques. In vitro cytotoxicity and apoptosis studies of CD-GEM conjugates were evaluated by various bioactivity assays on human cell lines, MCF-7 (human breast adenocarcinoma), and HeLa (cervical cancer) cell lines. The results of kinetic studies have shown a maximum drug loading efficacy of 17.0 mg of GEM per 50.0 mg of CDs. The CDs were found biocompatible, and the CD-GEM conjugates exhibited excellent bioactivity and exerted potent cytotoxicity against tumor cells with an IC50 value of 19.50 μg ml-1 in HeLa cells, which is lower than the IC50 value of pure GEM (∼20.10 μg ml-1). In vitro studies on CD-GEM conjugates demonstrated the potential to replace the conventional administration of GEM. CD-GEM conjugates are more stable, have a higher aqueous solubility, and are more cytotoxic as compared to GEM alone. The CD-GEM conjugates show reduced side effects in the normal cells along with excellent cellular uptake. Hence, CD-GEM conjugates are more selective toward cancerous cell lines as compared to non-cancerous cells. Also, the CD-GEM conjugates successfully induced early and late apoptosis in cancer cell lines and might be effective and safe to use for in vivo applications.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives*; Deoxycytidine/metabolism; Deoxycytidine/pharmacology
  6. Zahrina AK, Norsa'adah B, Hassan NB, Norazwany Y, Norhayati I, Roslan MH, et al.
    Asian Pac J Cancer Prev, 2014;15(21):9225-32.
    PMID: 25422205
    Ensuring adherence to chemotherapy is important to prevent disease progression, prolong survival and sustain good quality of life. Capecitabine is a complex chemotherapeutic agent with many side effects that might affect patient adherence to treatment. This cross sectional study aimed to determine adherence to capecitabine and its contributing factors among cancer outpatients in Malaysia. One hundred and thirteen patients on single regime capecitabine were recruited from Hospital Sultan Ismail and Hospital Kuala Lumpur from October 2013 to March 2014. Adherence was determined based on adherence score using validated Medication Compliance Questionnaire. Patient socio-demographics, disease, and treatment characteristics were obtained from medical records. Satisfaction score was measured using the validated Patient Satisfaction with Healthcare questionnaire. The mean adherence score was 96.1% (standard deviation: 3.29%). The significant contributing factors of adherence to capecitabine were Malay ethnicity [β=1.3; 95% confidence interval (CI): 0.21, 2.43; p value=0.020], being female [β=1.8; 95%CI: 0.61, 2.99; p value=0.003]), satisfaction score [β=0.08; 95%CI: 0.06, 1.46; p value=0.035], presence of nausea or vomiting [β=2.3; 95%CI: 1.12, 3.48; p value <0.001] and other side effects [β=1.45; 95%CI: 0.24, 2.65; p value=0.019]. Adherence to capecitabine was generally high in our local population. Attention should be given to non-Malay males and patients having nausea, vomiting or other side effects. Sufficient information, proactive assessment and appropriate management of side effects would improve patient satisfaction and thus create motivation to adhere to treatment plans.
    Matched MeSH terms: Deoxycytidine/adverse effects; Deoxycytidine/analogs & derivatives*; Deoxycytidine/therapeutic use
  7. Kamil M, Haron M, Yosuff N, Khalid I, Azman N
    J Coll Physicians Surg Pak, 2010 Jun;20(6):421-2.
    PMID: 20642979 DOI: 06.2010/JCPSP.421422
    A hospital based cross-sectional retrospective study was conducted to determine the frequency of hand foot syndrome (HFS) with Capecitabine as a single agent and in combination with Oxaliplatin. The study included 43 consecutive cases of colorectal carcinoma and conducted from June till December 2008. Patients on palliative care were excluded. SPSS was used for the application of chi-square test, by keeping the level of significance as p < 0.05. Fifteen (34.9%) patients developed HFS, 10 in the single-agent and 5 in the combination group. No significant association of HFS with either regimens was noted (p=0.876).
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/adverse effects; Deoxycytidine/analogs & derivatives*
  8. Maniam G, Mai CW, Zulkefeli M, Fu JY
    Nanomedicine (Lond), 2021 02;16(5):373-389.
    PMID: 33543651 DOI: 10.2217/nnm-2020-0374
    Aim: To synthesize niosomes co-encapsulating gemcitabine (GEM) and tocotrienols, and physicochemically characterize and evaluate the antipancreatic effects of the nanoformulation on Panc 10.05, SW 1990, AsPC-1 and BxPC-3 cells. Materials & methods: Niosomes-entrapping GEM and tocotrienols composed of Span 60, cholesterol and D-α-tocopheryl polyethylene glycol 1000 succinate were produced by Handjani-Vila and film hydration methods. Results: The film hydration produced vesicles measuring 161.9 ± 0.5 nm, approximately 50% smaller in size than Handjani-Vila method, with maximum entrapment efficiencies of 20.07 ± 0.22% for GEM and 34.52 ± 0.10% for tocotrienols. In Panc 10.05 cells, GEM's antiproliferative effect was enhanced 2.78-fold in combination with tocotrienols. Niosomes produced a significant ninefold enhancement in cytotoxicity of the combination, supported by significantly higher cellular uptake of GEM in the cells. Conclusion: This study is a proof of concept on the synthesis of dual-drug niosomes and their efficacy on pancreatic cancer cells in vitro.
    Matched MeSH terms: Deoxycytidine
  9. Soni N, Soni N, Pandey H, Maheshwari R, Kesharwani P, Tekade RK
    J Colloid Interface Sci, 2016 Nov 01;481:107-16.
    PMID: 27459173 DOI: 10.1016/j.jcis.2016.07.020
    Gemcitabine (GmcH) is an effective anti-cancer agent used in the chemotherapy of lung cancer. However, the clinical applications of GmcH has been impeded primarily due to its low blood residence time, unfavorable pharmacokinetic and pharmacodynamic (PK/PD) profile, and poor penetration in the complex environment of lung cancer cells. Thus, the present study aims to formulate GmcH loaded mannosylated solid lipid nanoparticles (GmcH-SLNs) for improving its drug uptake into the lung cancer cells. GmcH-SLNs were prepared by emulsification and solvent evaporation process, and surface modification was done with mannose using ring opening technique. The cellular toxicity and cell uptake studies were performed in A549 lung adenocarcinoma cell line. The developed nanoformulation appears to be proficient in targeted delivery of GmcH with improved therapeutic effectiveness and enhanced safety.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives*; Deoxycytidine/pharmacokinetics; Deoxycytidine/pharmacology
  10. Wahgiman NA, Salim N, Abdul Rahman MB, Ashari SE
    Int J Nanomedicine, 2019;14:7323-7338.
    PMID: 31686809 DOI: 10.2147/IJN.S212635
    Background: Gemcitabine (GEM) is a chemotherapeutic agent, which is known to battle cancer but challenging due to its hydrophilic nature. Nanoemulsion is water-in-oil (W/O) nanoemulsion shows potential as a carrier system in delivering gemcitabine to the cancer cell.

    Methods: The behaviour of GEM in MCT/surfactants/NaCl systems was studied in the ternary system at different ratios of Tween 80 and Span 80. The system with surfactant ratio 3:7 of Tween 80 and Span 80 was chosen for further study on the preparation of nanoemulsion formulation due to the highest isotropic region. Based on the selected ternary phase diagram, a composition of F1 was chosen and used for optimization by using the D-optimal mixture design. The interaction variables between medium chain triglyceride (MCT), surfactant mixture Tween 80: Span 80 (ratio 3:7), 0.9 % sodium chloride solution and gemcitabine were evaluated towards particle size as a response.

    Results: The results showed that NaCl solution and GEM gave more effects on particle size, polydispersity index and zeta potential of 141.57±0.05 nm, 0.168 and -37.10 mV, respectively. The optimized nanoemulsion showed good stability (no phase separation) against centrifugation test and storage at three different temperatures. The in vitro release of gemcitabine at different pH buffer solution was evaluated. The results showed the release of GEM in buffer pH 6.5 (45.19%) was higher than GEM in buffer pH 7.4 (13.62%). The cytotoxicity study showed that the optimized nanoemulsion containing GEM induced cytotoxicity towards A549 cell and at the same time reduced cytotoxicity towards MRC5 when compared to the control (GEM solution).

    Matched MeSH terms: Deoxycytidine/analogs & derivatives*; Deoxycytidine/pharmacology; Deoxycytidine/therapeutic use
  11. Yehya AHS, Subramaniam AV, Asif M, Kaur G, Abdul Majid AMS, Oon CE
    World J Gastroenterol, 2022 Aug 28;28(32):4620-4634.
    PMID: 36157930 DOI: 10.3748/wjg.v28.i32.4620
    BACKGROUND: Pancreatic cancer is the most aggressive cancer type. Gemcitabine is the first line chemo-drug used for pancreatic cancer but exerts a broad spectrum of organ toxicities and adverse effects in patients.

    AIM: To evaluate the anti-tumour activity and toxicological effects of Orthosiphon stamineus extract formulation (ID: C5EOSEW5050ESA trademarked as Nuva-staticTM), and gemcitabine combination on pancreatic xenograft model.

    METHODS: Mice were randomly divided into six groups of 6 mice each (n = 6) and given different treatments for 28 d. The study design consisted of a 2 x 3 factorial treatment structure, with gemcitabine (yes/no) by oral (at 1200 and 400 mg/kg per day). Human pancreatic cancer cells were injected subcutaneously into the flanks of athymic nude mice. C5EOSEW5050ESA (200 or 400 mg/kg per day) was administered orally, while gemcitabine (10 mg/kg per 3 d) was given intraperitoneally either alone or in combination treatment. Histopathological analyses of vital organs, tumour tissues, and incidence of lethality were analysed. Analyses of tumour necrosis and proliferation were determined by haematoxylin-eosin staining and immunohistochemistry for Ki-67, respectively.

    RESULTS: No signs of toxicity or damage to vital organs were observed in all treatment groups compared to the untreated group. C5EOSEW5050ESA at 200 mg/kg and gemcitabine combination had no additive antitumor effects compared to a single treatment. Remarkably, a comparably greater response in a reduction in tumour growth, Ki-67 protein expression, and necrosis was demonstrated by 400 mg/kg of C5EOSEW5050ESA and gemcitabine combination than that of the individual agents.

    CONCLUSION: These results highlighted the synergistic activity of C5EOSEW5050ESA with gemcitabine to reduce pancreatic tumour growth in mice compared to a single treatment. Thus, this study provides valuable insights into using C5EOSEW5050ESA as a complementary treatment with gemcitabine for pancreatic cancer.

    Matched MeSH terms: Deoxycytidine/analogs & derivatives
  12. Taghizadeh Davoudi E, Ibrahim Noordin M, Kadivar A, Kamalidehghan B, Farjam AS, Akbari Javar H
    Biomed Res Int, 2013;2013:495319.
    PMID: 24288681 DOI: 10.1155/2013/495319
    Gastrointestinal disturbances, such as nausea and vomiting, are considered amongst the main adverse effects associated with oral anticancer drugs due to their fast release in the gastrointestinal tract (GIT). Sustained release formulations with proper release profiles can overcome some side effects of conventional formulations. The current study was designed to prepare sustained release tablets of Capecitabine, which is approved by the Food and Drug Administration (FDA) for the treatment of advanced breast cancer, using hydroxypropyl methylcellulose (HPMC), carbomer934P, sodium alginate, and sodium bicarbonate. Tablets were prepared using the wet granulation method and characterized such that floating lag time, total floating time, hardness, friability, drug content, weight uniformity, and in vitro drug release were investigated. The sustained release tablets showed good hardness and passed the friability test. The tablets' floating lag time was determined to be 30-200 seconds, and it floated more than 24 hours and released the drug for 24 hours. Then, the stability test was done and compared with the initial samples. In conclusion, by adjusting the right ratios of the excipients including release-retarding gel-forming polymers like HPMC K4M, Na alginate, carbomer934P, and sodium bicarbonate, sustained release Capecitabine floating tablet was formulated.
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/adverse effects; Deoxycytidine/analogs & derivatives*; Deoxycytidine/chemistry
  13. Soon SS, Chia WK, Chan ML, Ho GF, Jian X, Deng YH, et al.
    PLoS One, 2014;9(9):e107866.
    PMID: 25250815 DOI: 10.1371/journal.pone.0107866
    Recent observational studies showed that post-operative aspirin use reduces cancer relapse and death in the earliest stages of colorectal cancer. We sought to evaluate the cost-effectiveness of aspirin as an adjuvant therapy in Stage I and II colorectal cancer patients aged 65 years and older.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives; Deoxycytidine/economics; Deoxycytidine/therapeutic use
  14. Wu YL, Zhou C, Liam CK, Wu G, Liu X, Zhong Z, et al.
    Ann Oncol, 2015 Sep;26(9):1883-1889.
    PMID: 26105600 DOI: 10.1093/annonc/mdv270
    BACKGROUND: The phase III, randomized, open-label ENSURE study (NCT01342965) evaluated first-line erlotinib versus gemcitabine/cisplatin (GP) in patients from China, Malaysia and the Philippines with epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC).

    PATIENTS AND METHODS: Patients ≥18 years old with histologically/cytologically confirmed stage IIIB/IV EGFR mutation-positive NSCLC and Eastern Cooperative Oncology Group performance status 0-2 were randomized 1:1 to receive erlotinib (oral; 150 mg once daily until progression/unacceptable toxicity) or GP [G 1250 mg/m(2) i.v. days 1 and 8 (3-weekly cycle); P 75 mg/m(2) i.v. day 1, (3-weekly cycle) for up to four cycles]. Primary end point: investigator-assessed progression-free survival (PFS). Other end points include objective response rate (ORR), overall survival (OS), and safety.

    RESULTS: A total of 217 patients were randomized: 110 to erlotinib and 107 to GP. Investigator-assessed median PFS was 11.0 months versus 5.5 months, erlotinib versus GP, respectively [hazard ratio (HR), 0.34, 95% confidence interval (CI) 0.22-0.51; log-rank P < 0.0001]. Independent Review Committee-assessed median PFS was consistent (HR, 0.42). Median OS was 26.3 versus 25.5 months, erlotinib versus GP, respectively (HR, 0.91, 95% CI 0.63-1.31; log-rank P = .607). ORR was 62.7% for erlotinib and 33.6% for GP. Treatment-related serious adverse events (AEs) occurred in 2.7% versus 10.6% of erlotinib and GP patients, respectively. The most common grade ≥3 AEs were rash (6.4%) with erlotinib, and neutropenia (25.0%), leukopenia (14.4%), and anemia (12.5%) with GP.

    CONCLUSION: These analyses demonstrate that first-line erlotinib provides a statistically significant improvement in PFS versus GP in Asian patients with EGFR mutation-positive NSCLC (NCT01342965).

    Matched MeSH terms: Deoxycytidine/adverse effects; Deoxycytidine/analogs & derivatives*; Deoxycytidine/therapeutic use
  15. Joshi SC, Pant I, Shukla AN, Anshari MA
    J Cancer Res Ther, 2008 8 9;4(2):99-101.
    PMID: 18688130
    Follow-up of colorectal carcinoma after therapy is based on symptoms, tumor markers, and imaging studies. Clinicians sometimes face diagnostic dilemmas because of unusual presentations on the imaging modalities coupled with rising serum markers. We report a case of colorectal carcinoma that presented with gastrointestinal symptoms 14 months after completion of treatment. Investigations showed rise in carcinoembryonic antigen (CEA). Suspecting disease recurrence, complete radioimaging workup was performed; the only abnormality detected was a smooth, hypodense area in the posterior third of the spleen on contrast-enhanced computed tomography abdomen. In view of the previous diagnosis of carcinoma colon, the symptoms reported by the patient, the elevated CEA, and the atypical CECT appearance, a diagnosis of splenic metastasis was made. The patient was subjected to splenectomy as a curative treatment. However, the histopathological report revealed it to be a splenic infarct. The present case reemphasizes the limitations of radiological studies in the follow-up of carcinoma colon.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives; Deoxycytidine/therapeutic use
  16. Leow CH, Liam CK
    Respirology, 2005 Nov;10(5):629-35.
    PMID: 16268917
    The aim of the study was to evaluate the response, survival advantage and toxicity profile of gemcitabine-carboplatin combination cytotoxic chemotherapy in patients with locally advanced and metastatic non-small cell lung cancer (NSCLC).
    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/analogs & derivatives
  17. Oon CE, Strell C, Yeong KY, Östman A, Prakash J
    Eur J Pharmacol, 2015 Jun 15;757:59-67.
    PMID: 25843411 DOI: 10.1016/j.ejphar.2015.03.064
    Gemcitabine remains the standard treatment for pancreatic cancer, although most patients acquire resistance to the therapy. Up-regulated in pancreatic cancer, SIRT1 is involved in tumorigenesis and drug resistance. However the mechanism through which SIRT1 regulates drug sensitivity in cancer cells is mainly unknown. We hypothesise that inhibiting SIRT1 activity may increase sensitivity of pancreatic cancer cells to gemcitabine treatment through the regulation of apototic cell death, cell cycle, epithelial-mesenschymal-transition (EMT) and senescence. We demonstrate that gemcitabine or 6-Chloro-2,3,4,9-tetrahydro-1 H-Carbazole-1-carboxamide (EX527) SIRT1 inhibitor reduces PANC-1 cell proliferation in vitro. EX527 enhanced sensitivity of PANC-1 cells to gemcitabine treatment through increased apoptosis. However, EX527 displayed no beneficial effect either as a monotreatment or in combination with gemcitabine in the modulation of cell cycle progression. Combination treatment did not reverse the two phenomena known to affect drug sensitivity, namely EMT and senescence, which are both induced by gemcitabine. Unexpectedly, EX527 promoted PANC-1 xenograft tumour growth in SCID mice compared to control group. Dual tX527 and gemcitabine displayed no synergistic effect compared to gemcitabine alone. The study reveals that SIRT1 is involved in chemoresistance and that inhibiting SIRT1 activity with EX527 sensitised PANC-1 cells to gemcitabine treatment in vitro. Sensitisation of cells is shown to be mainly through induction of micronuclei formation as a result of DNA damage and apoptosis in vitro. However, the absence of positive combinatorial effects in vivo indicates possible effects on cells of the tumor microenvironment and suggests caution regarding the clinical relevance of tissue culture findings with EX527.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives; Deoxycytidine/pharmacology
  18. Hii LW, Lim SE, Leong CO, Chin SY, Tan NP, Lai KS, et al.
    BMC Complement Altern Med, 2019 Sep 14;19(1):257.
    PMID: 31521140 DOI: 10.1186/s12906-019-2663-9
    BACKGROUND: Clinacanthus nutans extracts have been consumed by the cancer patients with the hope that the extracts can kill cancers more effectively than conventional chemotherapies. Our previous study reported its anti-inflammatory effects were caused by inhibiting Toll-like Receptor-4 (TLR-4) activation. However, we are unsure of its anticancer effect, and its interaction with existing chemotherapy.

    METHODS: We investigated the anti-proliferative efficacy of polar leaf extracts (LP), non-polar leaf extracts (LN), polar stem extract (SP) and non-polar stem extracts (SN) in human breast, colorectal, lung, endometrial, nasopharyngeal, and pancreatic cancer cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, MTT assay. The most potent extracts was tested along with gemcitabine using our established drug combination analysis. The effect of the combinatory treatment in apoptosis were quantified using enzyme-linked immunosorbent assay (ELISA), Annexin V assay, antibody array and immunoblotting. Statistical significance was analysed using one-way analysis of variance (ANOVA) and post hoc Dunnett's test. A p-value of less than 0.05 (p 

    Matched MeSH terms: Deoxycytidine/analogs & derivatives*; Deoxycytidine/pharmacology
  19. Wu YL, Lee V, Liam CK, Lu S, Park K, Srimuninnimit V, et al.
    Lung Cancer, 2018 12;126:1-8.
    PMID: 30527172 DOI: 10.1016/j.lungcan.2018.10.004
    OBJECTIVE: Patients with advanced non-small-cell lung cancer (NSCLC) with an adenocarcinoma component are recommended to undergo epidermal growth factor receptor (EGFR) mutation testing when being considered for EGFR targeted therapy. We conducted an exploratory analysis to inform the clinical utility of EGFR mutation testing in blood cell-free DNA using the cobas®EGFR Mutation Test v2.

    MATERIALS AND METHODS: Two EGFR mutation tests, a tissue-based assay (cobas® v1) and a tissue- and blood-based assay (cobas® v2) were used to analyze matched biopsy and blood samples (897 paired samples) from three Asian studies of first-line erlotinib with similar intent-to-treat populations. ENSURE was a phase III comparison of erlotinib and gemcitabine/platinum, FASTACT-2 was a phase III study of gemcitabine/platinum plus erlotinib or placebo, and ASPIRATION was a single-arm phase II study of erlotinib. Agreement statistics were evaluated, based on sensitivity and specificity between the two assays in subgroups of patients with increasing tumor burden.

    RESULTS: Patients with discordant EGFR (tissue+/plasma-) mutation status achieved longer progression-free and overall survival than those with concordant (tissue+/plasma+) mutation status. Tumor burden was significantly greater in patients with concordant versus discordant mutations. Pooled analyses of data from the three studies showed a sensitivity of 72.1% (95% confidence interval [CI] 67.8-76.1) and a specificity of 97.9% (95% CI 96.0-99.0) for blood-based testing; sensitivity was greatest in patients with larger baseline tumors.

    CONCLUSIONS: Blood-based EGFR mutation testing demonstrated high specificity and good sensitivity, and offers a convenient and easily accessible diagnostic method to complement tissue-based tests. Patients with a discordant mutation status in plasma and tissue, had improved survival outcomes compared with those with a concordant mutation status, which may be due to their lower tumor burden. These data help to inform the clinical utility of this blood-based assay for the detection of EGFR mutations.

    Matched MeSH terms: Deoxycytidine/administration & dosage; Deoxycytidine/analogs & derivatives
  20. Er JL, Goh PN, Lee CY, Tan YJ, Hii LW, Mai CW, et al.
    Apoptosis, 2018 Jun;23(5-6):343-355.
    PMID: 29740790 DOI: 10.1007/s10495-018-1459-6
    Pancreatic adenocarcinoma (PDAC) is a highly aggressive cancer with a high chance of recurrence, limited treatment options, and poor prognosis. A recent study has classified pancreatic cancers into four molecular subtypes: (1) squamous, (2) immunogenic, (3) pancreatic progenitor and (4) aberrantly differentiated endocrine exocrine. Among all the subtypes, the squamous subtype has the worst prognosis. This study aims to utilize large scale genomic datasets and computational systems biology to identify potential drugs targeting the squamous subtype of PDAC through combination therapy. Using the transcriptomic data available from the International Cancer Genome Consortium, Cancer Cell Line Encyclopedia and Connectivity Map, we identified 26 small molecules that could target the squamous subtype of PDAC. Among them include inhibitors targeting the SRC proto-oncogene (SRC) and the mitogen-activated protein kinase kinase 1/2 (MEK1/2). Further analyses demonstrated that the SRC inhibitors (dasatinib and PP2) and MEK1/2 inhibitor (pimasertib) synergized gemcitabine sensitivity specifically in the squamous subtype of PDAC cells (SW1990 and BxPC3), but not in the PDAC progenitor cells (AsPC1). Further analysis revealed that the synergistic effects are dependent on SRC or MEK1/2 activities, as overexpression of SRC or MEK1/2 completely abrogated the synergistic effects SRC inhibitors (dasatinib and PP2) and MEK1/2 inhibitor (pimasertib). In contrast, no significant toxicity was observed in the MRC5 human lung fibroblast and ARPE-19 human retinal pigment epithelial cells. Together, our findings suggest that combinations of SRC or MEK inhibitors with gemcitabine possess synergistic effects on the squamous subtype of PDAC cells and warrant further investigation.
    Matched MeSH terms: Deoxycytidine/analogs & derivatives*; Deoxycytidine/therapeutic use
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