Chemoprotection of transfer of multidrug resistance gene into human hematopoietic progenitor cell

Objective To observe the effect of the transfer of multidrug resistance gene (mdr1) into human hematopoietic progenitor cells (HPC) on the chemoprotection Methods Human CD34 + cells served as a target of mdr1 gene transfer Retroviral vector SF mdr containing human total length mdr1cDNA was introduced into packing cells GP envAM12 by liposome mediated transfection The mdr1 gene was transduced into human CD34 + cells by retroviral supernatants of packing cells The integration and expression of the mdr1 gene and its protein (P170) in transduced cells were determined by PCR, RT PCR, and flow cytometry The drug resistance of chemotherapy in transduced HPC was determined by culturing colonies Results The mdr1 gene was integrated and expressed in transduced CD34 + cells The efficiency of mdr1 gene transfer was 10%-14% Compared with untransduced controls, within a certain range of drug concentration, the number of drug resistant colony in transduced HPC for taxol, doxorubicin,VCR and VP16 were increased by 3 6±2 1 fold, 2 9±0 3 fold, 1 9±0 4 fold, and 3 5±0 5 fold, respectively Conclusion The transfer of the mdr1 gene into human HPC can increase the drug resistance of the transduced cells to corresponding chemotherapeutic drugs that may provide some degree of chemoprotection for HPC

Cancer risk in primary sclerosing cholangitis: Epidemiology,prevention, and surveillance strategies

Primary sclerosing cholangitis(PSC) is a rare cholestatic liver disease characterized by progressive fibroinflammatory destruction of the intra-and/or extrahepatic biliary ducts. While its features and disease course can be variable,most patients with PSC have concurrent inflammatory bowel disease and will eventually develop liver cirrhosis and end-stage liver disease, with liver transplantation representing the only potentially curative option. Importantly,PSC is associated with a significantly increased risk of malignancy compared to the general population, mainly cholangiocarcinoma, gallbladder carcinoma,hepatocellular carcinoma, and colorectal cancer, with nearly 50% of deaths in patients with PSC being due to cancer. Therefore, robust surveillance strategies are needed, though uncertainty remains regarding how to best do so. In this review, we discuss the epidemiology, prevention, and surveillance of cancers in patients with PSC. Where evidence is limited, we present pragmatic approaches based on currently available data and expert opinion.

Does a melatonin supplement alter the course of gastroesophageal reflux disease?

Symptomatic gastro-esophageal reflux disease(GERD) is a very common disease.The consequence of GERD is not only erosive esophagitis,but also esophageal stricture,Barrett's esophagus and extra-esophageal damage(including the lungs,throat,sinuses,middle ear and teeth).GERD and Barrett's esophagus are also identif ied as major risk factors for esophageal carcinoma.Therapy with melatonin prevents esophageal injury from acid-pepsin and acid-pepsin-bile exposure in animals,then further studies are required in humans to establish whether a melatonin supplement is able to protect the patients with GERD from erosions,Barrett's and neoplasia.

Low-Dose of the Sulforaphane Precursor Glucoraphanin as a Dietary Supplement Induces Chemoprotective Enzymes in Humans

Broccoli sprout (BS) supplements have been marketed for over a decade for the promising health beneficial effects of sulforaphane (SFN), which induces Nrf2 signaling and downstream chemoprotective genes, including phase 2 enzymes. Most commercially available BS supplements encapsulate heat-processed BS containing glucoraphanin (GR), which is hydrolyzed to SFN by the intestinal microbiota. However, the absorption behavior of SFN following the intake of such BS supplements is still unclear. Additionally, the GR dose (around 30 mg) recommended by many manufacturers of BS supplements is relatively lower than the effective dose determined in previous intervention studies. The aims of this study were to assess the effects of a single administration of a typical BS supplement containing lower doses of GR (30 or 60 mg from 3 or 6 capsules, respectively) on SFN absorption, and also to assess the serum activities of phase 2 enzymes as possible surrogate markers of the beneficial effects of SFN. Urinary excreted isothiocyanates and dithiocarbamates showed that the SFN absorption following administration of BS supplement was prolonged and varied among individuals, which conforms to the well-known characteristics of intestinal microbiota-mediated SFN absorption. The amount of SFN absorbed increased dose-dependently but not linear fashion (9.27 μmol and 13.5 μmol for 3 and 6 capsules, respectively). There was no significant difference in SFN bioavailability and the number of capsules consumed. Serum activities of phase 2 enzymes glutathione S-transferase (GST) and NAD(P)H: quinone oxidoreductase 1 (NQO1), which have been reported to display “chemoprotected states” in organs such as the liver, were dose-dependently and synchronously elevated (p < 0.05) following BS supplement intake. This suggests that a low dose of GR (30 mg) exerts chemoprotective effects in humans. In conclusion, our findings will be useful in future clinical studies investigating the chemoprotective effects of SFN, and for the development of BS supplement products.

Effects of selenomethionine on acute toxicities from concurrent chemoradiation for inoperable stage Ⅲ nonsmall cell lung cancer

AIM: To prospectively determine the safety and tolerability of oral L-selenomethionine(SLM) with concurrent chemoradiation(CCRT) for Stage Ⅲ non-small cell lung cancer(NSCLC) and estimate if the incidence and/or severity of adverse events could be reduced by its use.METHODS: Sixteen patients with stage Ⅲ NSCLC were accrued to this single arm, phase Ⅱ study. CCRT consisted of radiation given at 2 Gy per fraction for 30-33 fractions, 5 d per week with concurrent weekly Ⅳ paclitaxel 50 mg/m2 followed by carboplatin dosed at an area under the time-concentration curve of 2. SLM was dosed in a loading phase at 4800 μg twice daily for one week prior to CCRT followed by once daily dosing during treatment. RESULTS: No selenium-related toxicity was observed. Analysis revealed grade 3 or higher esophagitis in 3 of 16 patients(19%), pneumonitis in 0, leukopenia in 2(12.5%), and anemia in 1(6%); the latter two were significantly reduced when compared to the protocolstated expected rate of 35%(P = 0.045 for leukopenia, and P < 0.01 for anemia). Median overall survival was 14.9 mo and median failure-free survival was 9 mo(95%CI: 3.3-21.5).CONCLUSION: There may be some protective benefit of selenium in the setting of CCRT for inoperable NSCLC. The data suggests decreased rates of myelosuppression when compared to similarly-treated historical and contemporary controls. Further evaluation of selenium in this setting may be warranted.

Chemoprotective activity of aqueous leaf extract of Acalypha wilkesiana against cyclophosphamide-induced toxicity in rats

Objective:To investigate the protective effect of aqueous leaf extract of Acalypha(A.)wilkesiana Muell.Arg(Euphorbiaceae)against cyclophosphamide-induced toxicity in albino rats.Methods:Twenty male albino rats were randomly divided into five groups of four animals each.The control group(Ⅰ)was fed with pellets and distilled water,while group Ⅱ was orally administered with only 20 mg/kg cyclophosphamide.Groups Ⅲ,Ⅳ and Ⅴ were coadministered with 20 mg/kg body weight cyclophosphamide and 110,220 and 440 mg/kg body weight A.wilkesiana leaf extract,respectively,for 7 d.After treatment,liver and kidney function biomarkers,haematological parameters,liver antioxidants,and mitochondrial membrane permeability transition pore opening were investigated.Results:A.wilkesiana leaf extract significantly reduced(P<0.05)cyclophosphamide-induced increase in plasma aspartate aminotransferase,alanine aminotransferase,creatinine,uric acid and urea.It increased superoxide dismutase,catalase,glutathione-S-transferase activities and reduced glutathione levels.It also increased packed cell volume count,hemoglobin concentration and white blood cell count while inhibiting the induction of mitochondrial swelling.Conclusions:This study demonstrates that aqueous extract of A.wilkesiana leaf protected tissues against cyclophosphamide-induced oxidative damage.

Randomized phase Ⅱ trial of selenomethionine as a modulator of efficacy and toxicity of chemoradiation in squamous cell carcinoma of the head and neck

AIM: To investigate whether selenomethionine(SLM) reduces mucositis incidence in patients with head and neck squamous cell cancer(HNSCC) undergoing concurrent chemoradiation(CRT).METHODS: In this multi-institutional, randomized, double-blind phase Ⅱ trial, patients with Stage Ⅲ or Ⅳ HNSCC received SLM 3600 μg/m2 or placebo twice daily for 7 d prior to CRT, once daily during CRT, and daily for 3 wk following CRT. CRT consisted of 70 Gy at 2 Gy per fraction with cisplatin 100 mg/m2 Ⅳ on days 1, 22, and 43. RESULTS: Eighteen patients were randomized, 10 received SLM, and there were no differences in baseline factors. There was no difference in mucositis or patientreported side effects between groups. There was no difference in overall or relapse-free survival at 12 mo.CONCLUSION: Addition of SLM to CRT for HNSCC was well-tolerated but did not lower the incidence of severe mucositis or improve quality of life or survival outcomes.

Perspective on dietary isothiocyanates in the prevention,development and treatment of cancer

Epidemiological evidence has highlighted the association of specific diets and a lower incidence of cancer.Foremost,the Mediterranean diet provides high levels of polyphenolics and a high consumption of healthier fats,e.g.,as from olive oil.In the Mediterranean region the consumption of vegetables is elevated providing a class of compounds,the isothiocyanates(ITCs)as found in the cabbage family.The ITCs have raised great interest for their health benefits over the past few decades.Some of the key ITC compounds,sulforaphane,phenethylisothiocyanate and benzyl isothiocyanate,have been studied in vitro and in vivo and the data support their promise for cancer chemoprevention,as anti-tumor agents,and for chemoprotection of normal tissues and organs.Along with other polyphenolic compounds in the diet,in general,they also possess key anti-inflammatory properties thus satisfying the criteria for compounds that could intervene in cancer initiation and progression.In this review we provide a larger overview of the advantages of including ITCs in the diet as food or as supplements and speculate on what could constitute a valuable therapeutic strategy for improving and sustaining good health and countering cancer disease in humans.