SciCombinator

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Concept: Doxorubicin

319

Background Prior studies with the use of a prospective-retrospective design including archival tumor samples have shown that gene-expression assays provide clinically useful prognostic information. However, a prospectively conducted study in a uniformly treated population provides the highest level of evidence supporting the clinical validity and usefulness of a biomarker. Methods We performed a prospective trial involving women with hormone-receptor-positive, human epidermal growth factor receptor type 2 (HER2)-negative, axillary node-negative breast cancer with tumors of 1.1 to 5.0 cm in the greatest dimension (or 0.6 to 1.0 cm in the greatest dimension and intermediate or high tumor grade) who met established guidelines for the consideration of adjuvant chemotherapy on the basis of clinicopathologic features. A reverse-transcriptase-polymerase-chain-reaction assay of 21 genes was performed on the paraffin-embedded tumor tissue, and the results were used to calculate a score indicating the risk of breast-cancer recurrence; patients were assigned to receive endocrine therapy without chemotherapy if they had a recurrence score of 0 to 10, indicating a very low risk of recurrence (on a scale of 0 to 100, with higher scores indicating a greater risk of recurrence). Results Of the 10,253 eligible women enrolled, 1626 women (15.9%) who had a recurrence score of 0 to 10 were assigned to receive endocrine therapy alone without chemotherapy. At 5 years, in this patient population, the rate of invasive disease-free survival was 93.8% (95% confidence interval [CI], 92.4 to 94.9), the rate of freedom from recurrence of breast cancer at a distant site was 99.3% (95% CI, 98.7 to 99.6), the rate of freedom from recurrence of breast cancer at a distant or local-regional site was 98.7% (95% CI, 97.9 to 99.2), and the rate of overall survival was 98.0% (95% CI, 97.1 to 98.6). Conclusions Among patients with hormone-receptor-positive, HER2-negative, axillary node-negative breast cancer who met established guidelines for the recommendation of adjuvant chemotherapy on the basis of clinicopathologic features, those with tumors that had a favorable gene-expression profile had very low rates of recurrence at 5 years with endocrine therapy alone. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00310180 .).

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Epidermal growth factor receptor, Epidermal growth factor, Chemotherapy, Doxorubicin

167

To date, gold nanoparticles (AuNPs) have been investigated for diverse bioapplications. Generally, AuNPs are engineered to possess surface coating with organic/inorganic shells to increase colloidal stability in biological solutions and to facilitate chemical conjugation. In the present study, we developed a strategy to prepare dextran-coated AuNPs with control over its size by simply boiling an aqueous solution of Au salt and dextran, in which dextran serves as both reducing agent for AuNP (Au(0)) formation from Au(III) and AuNP surface coating material. The prepared dextran-coated AuNPs (dAuNPs) maintained its colloidal stability under high temperature, high salt concentration, and extreme pH. Importantly, the dAuNP remarkably improved efficacy of an anti-cancer agent, doxorubicin (Dox), when harnessed as a Dox delivery carrier. The half-maximal inhibitory concentration (EC50) of Dox-conjugated dAuNP with diameter of 170 nm was ∼9 pM in HeLa cells, which was 1.1 × 10(5) times lower than that of free Dox and lower than any previously reported values of Dox-nanoparticle complex. Interestingly, smaller AuNPs with 30 and 70 nm showed about 10 times higher EC50 than 170 nm AuNPs when treated to HeLa cells after conjugation with Dox. To achieve high cytotoxicity as cancer therapeutics, Dox should be delivered into nucleus to intercalate with DNA double helix. We show here that Dox-AuNPs was far more efficient as an anti-cancer drug than free Dox by releasing from AuNPs through spontaneous degradation of dextran, allowing free diffusion and nuclear uptake of Dox. We also revealed that larger AuNPs with lower degree of dextran crosslinking promoted faster degradation of dextran shells.

Concepts: DNA, Cell nucleus, Nanoparticle, Chemotherapy, Concentration, Chemistry, Gold, Doxorubicin

167

Mesoporous silica-encapsulated gold nanorods (GNRs@mSiO(2)) have great potential both in photothermal therapy and drug delivery. In this paper, we firstly developed GNRs@mSiO(2) as a synergistic therapy tool for delivery heat and drug to the tumorigenic region. We studied the ablation of tumor both in vitro and in vivo by the combination of photothermal therapy and chemotherapy using doxorubicin (DOX)-loaded GNRs@mSiO(2). Significantly greater cell killing was observed when A549 cells incubated with DOX-loaded GNRs@mSiO(2) were irradiated with near-infrared (NIR) illumination, attributable to both GNRs@mSiO(2)-mediated photothermal ablation and cytotoxicity of light-triggered DOX release. We then performed in vivo therapy studies and observed a promising tumor treatment. Compared with chemotherapy or photothermal treatment alone, the combined treatment showed a synergistic effect, resulting in higher therapeutic efficacy. Furthermore, the lower systematic toxicity of GNRs@mSiO(2) has been validated.

Concepts: DNA, Cancer, Oncology, Chemotherapy, Therapy, Efficacy, Doxorubicin, Photothermal Therapy

165

The inherently toxic nature of chemotherapy drugs is essential for them to kill cancer cells but is also the source of the detrimental side effects experienced by patients. One strategy to reduce these side effects is to limit the healthy tissue exposure by encapsulating the drugs in a vehicle that demonstrates a very low leak rate in circulation while simultaneously having the potential for rapid release once inside the tumor. Designing a vehicle with these two opposing properties is the major challenge in the field of drug delivery. A triggering event is required to change the vehicle from its stable circulating state to its unstable release state. A unique mechanical actuation type trigger is possible by harnessing the size changes that occur when microbubbles interact with ultrasound. These mechanical actuations can burst liposomes and cell membranes alike allowing for rapid drug release and facilitating delivery into nearby cells. The tight focusing ability of the ultrasound to just a few cubic millimeters allows for precise control over the tissue location where the microbubbles destabilize the vehicles. This allows the ultrasound to highlight the tumor tissue and cause rapid drug release from any carrier present. Different vehicle designs have been demonstrated from carrying drug on just the surface of the microbubble itself to encapsulating the microbubble along with the drug within a liposome. In the future, nanoparticles may extend the circulation half-life of these ultrasound triggerable drug-delivery vehicles by acting as nucleation sites of ultrasound-induced mechanical actuation. In addition to the drug delivery capability, the microbubble size changes can also be used to create imaging contrast agents that could allow the internal chemical environment of a tumor to be studied to help improve the diagnosis and detection of cancer. The ability to attain truly tumor-specific release from circulating drug-delivery vehicles is an exciting future prospect to reduce chemotherapy side effects while increasing drug effectiveness.

Concepts: Immune system, Cancer, Oncology, Cell membrane, Chemotherapy, Neoplasm, Doxorubicin, Experimental cancer treatment

142

Liposomes are nanocarriers that deliver the payloads at the target site, leading to therapeutic drug concentrations at the diseased site and reduced toxic effects in healthy tissues. Several approaches have been used to enhance the ability of the nanocarrier to target the specific tissues, including ligand-targeted liposomes and stimuli-responsive liposomes. Ligand-targeted liposomes exhibit higher uptake by the target tissue due to the targeting ligand attached to the surface, while, the stimuli-responsive liposomes do not release their cargo unless they expose to an endogenous or exogenous stimulant at the target site. In this review, we mainly focus on the liposomes that are responsive to pathologically increased levels of enzymes at the target site. Enzyme-responsive liposomes release their cargo upon contact with the enzyme through several destabilization mechanisms: a) structural perturbation in the lipid bilayer, b) removal of a shielding polymer from the surface and increased cellular uptake, c) cleavage of a lipopeptide or lipopolymer incorporated in the bilayer, and d) activation of a prodrug in the liposomes.

Concepts: Protein, Medicine, Cancer, Enzyme, Cure, Poison, Doxorubicin, Recreational drug use

77

Background Among patients in whom childhood cancer was diagnosed in the 1970s and 1980s, 18% of those who survived for 5 years died within the subsequent 25 years. In recent decades, cancer treatments have been modified with the goal of reducing life-threatening late effects. Methods We evaluated late mortality among 34,033 patients in the Childhood Cancer Survivor Study cohort who survived at least 5 years after childhood cancer (i.e., cancer diagnosed before the age of 21 years) for which treatment was initiated during the period from 1970 through 1999. The median follow-up was 21 years (range, 5 to 38). We evaluated demographic and disease factors that were associated with death from health-related causes (i.e., conditions that exclude recurrence or progression of the original cancer and external causes but include the late effects of cancer therapy) using cumulative incidence and piecewise exponential models to estimate relative rates and 95% confidence intervals. Results Of the 3958 deaths that occurred during the study period, 1618 (41%) were attributable to health-related causes, including 746 deaths from subsequent neoplasms, 241 from cardiac causes, 137 from pulmonary causes, and 494 from other causes. A reduction in 15-year mortality was observed for death from any cause (from 12.4% in the early 1970s to 6.0% in the 1990s, P<0.001 for trend) and from health-related causes (from 3.5% to 2.1%, P<0.001 for trend). These reductions were attributable to decreases in the rates of death from subsequent neoplasm (P<0.001), cardiac causes (P<0.001), and pulmonary causes (P=0.04). Changes in therapy according to decade included reduced rates of cranial radiotherapy for acute lymphoblastic leukemia (85% in the 1970s, 51% in the 1980s, and 19% in the 1990s), of abdominal radiotherapy for Wilms' tumor (78%, 53%, and 43%, respectively), of chest radiotherapy for Hodgkin's lymphoma (87%, 79%, and 61%, respectively), and of anthracycline exposure. Reduction in treatment exposure was associated with reduced late mortality among survivors of acute lymphoblastic leukemia and Wilms' tumor. Conclusions The strategy of lowering therapeutic exposure has contributed to an observed decline in late mortality among 5-year survivors of childhood cancer. (Funded by the National Cancer Institute and the American Lebanese-Syrian Associated Charities.).

Concepts: Cancer, Oncology, Death, Tumor, Neoplasm, Leukemia, Acute lymphoblastic leukemia, Doxorubicin

63

The American Cancer Society (ACS), Centers for Disease Control and Prevention (CDC), National Cancer Institute (NCI), and North American Association of Central Cancer Registries (NAACCR) collaborate annually to produce updated, national cancer statistics. This Annual Report includes a focus on breast cancer incidence by subtype using new, national-level data.

Concepts: Epidemiology, Cancer, Breast cancer, National Cancer Institute, American Cancer Society, North America, Doxorubicin, Cancer organizations

31

One third of patients with triple-negative breast cancer (TNBC) achieve pathologic complete response (pCR) with standard neoadjuvant chemotherapy (NACT). CALGB 40603 (Alliance), a 2 × 2 factorial, open-label, randomized phase II trial, evaluated the impact of adding carboplatin and/or bevacizumab.

Concepts: Cancer, Breast cancer, Metastasis, Lung cancer, Cancer staging, Chemotherapy, Doxorubicin, Antineoplastic drugs

30

Lymphocyte-predominant Hodgkin disease is a rare form of Hodgkin lymphoma that is recognized as a separate histopathological entity. This disease tends to have multiple relapses, but has an overall good prognosis. Owing to its rarity, and the prolonged time period between recurrence and transformation events, there is no consensus regarding optimal management. However, the National Comprehensive Cancer Network guidelines indicate that for early stages, appropriate treatment is radiotherapy. Several management options have been reported including observation, radiation, chemotherapy, combined chemoradiotherapy, and anti-CD20 antibody therapy. Salvage therapy remains effective in inducing prolonged remission in patients with relapsed/refractory disease.

Concepts: Medicine, Cancer, Chemotherapy, Radiation therapy, Lymphoma, Hodgkin's lymphoma, Doxorubicin, Non-Hodgkin lymphoma

29

In the present study, we evaluated the efficacy and safety of rituximab in combination with standard doxorubicin, bleomycin, vinblastine, and dacarbazine (RABVD) in patients with classical Hodgkin lymphoma (cHL). In this phase 2 study, patients with chemotherapy-naive, advanced-stage cHL were treated with rituximab 375 mg/m(2) weekly for 6 weeks and standard ABVD for 6 cycles. The primary outcome was event-free survival (EFS) at 5 years. Eighty-five patients were enrolled, of whom 78 were eligible. With a median follow-up duration of 68 months (range, 26-110), and based on an intent-to-treat analysis, the 5-year EFS and overall survival rates were 83% and 96%, respectively. The 5-year EFS for patients with stage III/IV cHL was 82%. Furthermore, the 5-year EFS for patients with an International Prognostic Score of 0-2 was 88% and for those with a score of > 2, it was 73%. The most frequent treatment-related grade 3 or 4 adverse events were neutropenia (23%), fatigue (9%), and nausea (8%). Our results demonstrate that the addition of rituximab to ABVD is safe and has a promising clinical activity in patients with advanced-stage cHL. These data are currently being confirmed in a multicenter randomized trial.

Concepts: Randomized controlled trial, Chemotherapy, Lymphoma, Hodgkin's lymphoma, Doxorubicin, ABVD, Antineoplastic drugs, Vinblastine