Addition of 5-fluorouracil to doxorubicin-paclitaxel sequence increases caspase-dependent apoptosis in breast cancer cell lines

Leveraging chromatin packing domains to target chemoevasion in vivo

Cancer cells exhibit a remarkable resilience to cytotoxic stress, often adapting through transcriptional changes linked to alterations in chromatin structure. In several types of cancer, these adaptations involve epigenetic modifications and restructuring of topologically associating domains (TADs). However, the underlying principles by which chromatin architecture facilitates such adaptability across different cancers remain poorly understood. To investigate the role of chromatin in this process, we developed a physics-based mechanistic model that connects chromatin organization to cell fate decisions, specifically survival following chemotherapy. Our model builds on the observation that chromatin forms packing domains, which influence transcriptional efficiency through macromolecular crowding. The model accurately predicts chemoevasion in vitro, suggesting that changes in packing domains affect the likelihood of survival. Consistent results across diverse cancer types indicate that the model captures fundamental principles of chromatin-mediated adaptation, independent of the specific cancer or chemotherapy mechanisms involved. Based on these insights, we hypothesized that compounds capable of modulating packing domains, termed Transcriptional Plasticity Regulators (TPRs), could prevent cellular adaptation to chemotherapy. Using live-cell chromatin imaging, we conducted a compound screen that identified several TPRs which synergistically enhanced chemotherapy-induced cell death. The most effective TPR significantly improved therapeutic outcomes in a patient-derived xenograft (PDX) model of ovarian cancer. These findings underscore the central role of chromatin in cellular adaptation to cytotoxic stress and present a novel framework for enhancing cancer therapies, with broad potential across multiple cancer types.

Genomic strategies for drug repurposing

Functional genomics, a multidisciplinary subject, investigates the functions of genes and their products in biological systems to better understand diseases and find new drugs. Drug repurposing is an economically efficient approach that entails discovering novel therapeutic applications for already-available medications. Genomics enables the identification of illness and therapeutic molecular characteristics and interactions, which in turn facilitates the process of drug repurposing. Techniques like gene expression profiling and Mendelian randomization are helpful in identifying possible medication candidates. Progress in computer science allows for the investigation and modeling of gene expression networks that involve large amounts of data. The amalgamation of data concerning DNA, RNA, and protein functions bears similarity to pharmacogenomics, a crucial aspect in crafting cancer therapeutics. Functional genomics in drug discovery, particularly for cancer, is still not thoroughly investigated, despite the existence of a significant amount of literature on the subject. Next-generation sequencing and proteomics present highly intriguing opportunities. Publicly available databases and mining techniques facilitate the development of cancer treatments based on functional genomics. Broadening the exploration and utilization of functional genomics holds significant potential for advancing drug discovery and repurposing, particularly within the realm of oncology.

Advancing targeted combination chemotherapy in triple negative breast cancer: nucleolin aptamer-mediated controlled drug release

BACKGROUND

Triple-negative breast cancer (TNBC) is a recurrent, heterogeneous, and invasive form of breast cancer. The treatment of TNBC patients with paclitaxel and fluorouracil in a sequential manner has shown promising outcomes. However, it is challenging to deliver these chemotherapeutic agents sequentially to TNBC tumors. We aim to explore a precision therapy strategy for TNBC through the sequential delivery of paclitaxel and fluorouracil.

METHODS

We developed a dual chemo-loaded aptamer with redox-sensitive caged paclitaxel for rapid release and non-cleavable caged fluorouracil for slow release. The binding affinity to the target protein was validated using Enzyme-linked oligonucleotide assays and Surface plasmon resonance assays. The targeting and internalization abilities into tumors were confirmed using Flow cytometry assays and Confocal microscopy assays. The inhibitory effects on TNBC progression were evaluated by pharmacological studies in vitro and in vivo.

RESULTS

Various redox-responsive aptamer-paclitaxel conjugates were synthesized. Among them, AS1411-paclitaxel conjugate with a thioether linker (ASP) exhibited high anti-proliferation ability against TNBC cells, and its targeting ability was further improved through fluorouracil modification. The fluorouracil modified AS1411-paclitaxel conjugate with a thioether linker (FASP) exhibited effective targeting of TNBC cells and significantly improved the inhibitory effects on TNBC progression in vitro and in vivo.

CONCLUSIONS

This study successfully developed fluorouracil-modified AS1411-paclitaxel conjugates with a thioether linker for targeted combination chemotherapy in TNBC. These conjugates demonstrated efficient recognition of TNBC cells, enabling targeted delivery and controlled release of paclitaxel and fluorouracil. This approach resulted in synergistic antitumor effects and reduced toxicity in vivo. However, challenges related to stability, immunogenicity, and scalability need to be further investigated for future translational applications.

Plasmonic Functional Assay Platform Determines the Therapeutic Profile of Cancer Cells

Functional assay platforms could identify the biophysical properties of cells and their therapeutic response to drug treatments. Despite their strong ability to assess cellular pathways, functional assays require large tissue samples, long-term cell culture, and bulk measurements. Even though such a drawback is still valid, these limitations did not hinder the interest in these platforms for their capacity to reveal drug susceptibility. Some of the limitations could be overcome with single-cell functional assays by identifying subpopulations using small sample volumes. Along this direction, in this article, we developed a high-throughput plasmonic functional assay platform to identify the growth profile of cells and their therapeutic profile under therapies using mass and growth rate statistics of individual cells. Our technology could determine populations' growth profiles using the growth rate data of multiple single cells of the same population. Evaluating spectral variations based on the plasmonic diffraction field intensity images in real time, we could simultaneously monitor the mass change for the cells within the field of view of a camera with the capacity of > ∼500 cells/h scanning rate. Our technology could determine the therapeutic profile of cells under cancer drugs within few hours, while the classical techniques require days to show reduction in viability due to antitumor effects. The platform could reveal the heterogeneity within the therapeutic profile of populations and determine subpopulations showing resistance to drug therapies. As a proof-of-principle demonstration, we studied the growth profile of MCF-7 cells and their therapeutic behavior to standard-of-care drugs that have antitumor effects as shown in the literature, including difluoromethylornithine (DFMO), 5-fluorouracil (5-FU), paclitaxel (PTX), and doxorubicin (Dox). We successfully demonstrated the resistant behavior of an MCF-7 variant that could survive in the presence of DFMO. More importantly, we could precisely identify synergic and antagonistic effects of drug combinations based on the order of use in cancer therapy. Rapidly assessing the therapeutic profile of cancer cells, our plasmonic functional assay platform could be used to reveal personalized drug therapies for cancer patients.

Hybrid peptides as platform for synchronized combination therapy

Combination therapy, where two or more therapeutic agents are combined to target different cellular pathways, is an effective tool in cancer treatment but often difficult to execute. Here we present the collagen peptide-based platform that allows for synchronous and colocalized cellular delivery of three different agents. The peptide is a hybrid between collagen and cell penetrating peptide (CPP) that assembles into a heterotrimer helix and forms fully organic, high aspect ratio nanoparticles. The validity of the approach was tested with three chemically different agents (Paclitaxel, Doxorubicin, and 5-Fluorouracil; a combination used in clinical treatment of (ER)-positive and (PR)-positive breast cancer) conjugated to N-terminus of the peptide. The design of this peptide-based drug delivery system provides several advantages: it avoids drug loading problems; removes the need for orthogonal synthesis; and allows for colocalized delivery of up to three drugs (which leads to the same biodistribution for each drug). In addition, hybrid collagen/CPP peptides are known to enhance cellular uptake and improve solubility of drugs. The synergistic effect, in terms of enhanced efficacy, of the Paclitaxel-Doxorubicin-5-Fluorouracil combination was also calculated. We envision self-assembling peptides as a platform for drug codelivery that can be expanded into a library of personalized combinations that may also include other functionalities like targeting or imaging.

2'-Fucosyllactose Suppresses Angiogenesis and Alleviates Toxic Effects of 5-Fu in a HCT116 Colon Tumor-Bearing Model

The present study was aimed at examining the anti-tumor effects and molecular mechanisms of 2'-fucosyllactose (2'-FL). At the beginning, the viabilities of four types of colon cancer cells were analyzed after exposure to increasing concentrations of 2'-FL, and HCT116 cells were selected as the sensitive ones, which were applied in the further experiments; then, interestingly, 2'-FL (102.35 µM) was found to induce apoptosis of HCT116 cells, which coincides with significant changes in VEGFA/VEGFR2/p-PI3K/p-Akt/cleaved Caspase3 proteins. Next, in a tumor-bearing nude mouse model, HCT116 was chosen as the sensitive cell line, and 5-fluorouracil (5-Fu) was chosen as the positive medicine. It was noteworthy that both 2'-FL group (2.41 ± 0.57 g) and 2'FL/5-Fu group (1.22 ± 0.35 g) had a significantly lower tumor weight compared with the control (3.87 ± 0.79 g), suggesting 2'-FL could inhibit colon cancer. Since 2'-FL reduced the number of new blood vessels and the malignancy of tumors, we confirmed that 2'-FL effectively inhibited HCT116 tumors, and its mechanism was achieved by regulating the VEGFA/VEGFR2/PI3K/Akt/Caspase3 pathway. Moreover, though HE staining and organ index measurement, 2'-FL was validated to alleviate toxic effects on liver and kidney tissue when combining with 5-Fu. In conclusion, 2'-FL had certain anti-tumor and detoxification effects.

Heat/pH-boosted release of 5-fluorouracil and albumin-bound paclitaxel from Cu-doped layered double hydroxide nanomedicine for synergistical chemo-photo-therapy of breast cancer

Considerable attention has been devoted to nanomedicine development for breast cancer therapy, while the therapeutic efficiency is far from satisfactory owing to non-specific biodistribution-caused side effects and limitation of single modal treatment. In this study, we have developed a novel nanomedicine for efficient combination breast cancer therapy. This nanomedicine was based on copper-doped layered double hydroxide (Cu-LDH) nanoparticles loaded with two FDA-approved anticancer drugs, i.e. 5-fluorouracil (5-FU) and albumin-bound paclitaxel (nAb-PTX) with complementary chemotherapeutic actions. The 5-FU/Cu-LDH@nAb-PTX nanomedicine showed pH-sensitive heat-facilitated therapeutic on-demand release and demonstrated the moderate-to-strong synergy of photothermal therapy and chemotherapy in inducing apoptosis of breast cancer cells (4 T1). This nanomedicine had a high colloidal stability in saline and serum, and efficiently accumulated in the tumor tissue. Remarkably, this nanomedicine nearly eliminated 4 T1 tumors in vivo after a two-course treatment under mild 808 nm laser irradiation (0.75 W/cm², 3 min) at very low doses of 5-FU and nAb-PTX (0.25 and 0.50 mg/kg, 8-50 times less than that used in other nanoformulations), without observable side effects. Therefore, this research provides a novel approach to designing multifunctional nanomedicines for on-demand release of chemotherapeutics to cost-effectively treat breast cancer with minimal side effects in future clinic applications.

Optimized 5-Fluorouridine Prodrug for Co-Loading with Doxorubicin in Clinically Relevant Liposomes

Liposome-based drug delivery systems have allowed for better drug tolerability and longer circulation times but are often optimized for a single agent due to the inherent difficulty of co-encapsulating two drugs with differing chemical profiles. Here, we design and test a prodrug based on a ribosylated nucleoside form of 5-fluorouracil, 5-fluorouridine (5FUR), with the final purpose of co-encapsulation with doxorubicin (DOX) in liposomes. To improve the loading of 5FUR, we developed two 5FUR prodrugs that involved the conjugation of either one or three moieties of tryptophan (W) known respectively as, 5FUR−W and 5FUR−W₃. 5FUR−W demonstrated greater chemical stability than 5FUR−W3 and allowed for improved loading with fewer possible byproducts from tryptophan hydrolysis. Varied drug ratios of 5FUR−W: DOX were encapsulated for in vivo testing in the highly aggressive 4T1 murine breast cancer model. A liposomal molar ratio of 2.5 5FUR−W: DOX achieved a 62.6% reduction in tumor size compared to the untreated control group and a 33% reduction compared to clinical doxorubicin liposomes in a proof-of-concept study to demonstrate the viability of the co-encapsulated liposomes. We believe that the new prodrug 5FUR−W demonstrates a prodrug design with clinical translatability by reducing the number of byproducts produced by the hydrolysis of tryptophan, while also allowing for loading flexibility.

Protective effects of nuclear factor erythroid 2-related factor on oxidative stress and apoptosis in the testis of mice before adulthood

Oxidative stress disrupts the intracellular redox balance that modulate many signaling pathways, including nuclear factor erythroid 2-related factor 2 (Nrf2)/Keap1 signaling. However, the antioxidant roles of Nrf2 in the testis before adulthood have not been reported. Accordingly, in this study, we aimed to investigate the effects of the Nrf2 antioxidant system on protection of testicular cells against oxidative stress at different stages of development in the testis of mice before adulthood. Male mice (1, 2, 4, and 8 weeks old) were used, and their relative testes weights were calculated. Malondialdehyde (MDA) contents and superoxide dismutase (SOD) activity were detected to evaluate the antioxidant capacity in the testes. Additionally, Nrf2 signaling pathway and mitochondrial apoptotic pathway proteins were evaluated by western blotting, and the localizations of Nrf2, protein gene product (PGP) 9.5, and activated-caspase 3 in testicular cells were examined using immunohistochemistry. The results showed that the activities of caspase-8 and caspase-3 and the number of activated-caspase 3-positive testicular cells per tubule were increased after 1 week of age. Moreover, MDA contents were increased and SOD activity was decreased with age in mouse testes before adulthood. The expression of PGP9.5 was increased, as well as the number of positive testicular cells per tubule. In addition, Nrf2 translocation to the nuclei of testicular cells also increased, accompanied by activation of the Nrf2/Keap1 signaling pathway. Moreover, nuclear factor-κB was inhibited, and the mitochondrial apoptotic pathway was activated in mouse testes before adulthood. Overall, our findings demonstrated that oxidative stress increased with age in mouse testes before adulthood and that oxidative stress could induce apoptosis in testicular cells. However, testicular cells are still in a rapid proliferative state owing to the antioxidant protection of Nrf2. Thus, our study provided new insights into oxidative stress-mediated impairment of spermatogenesis with age in mouse testes before adulthood and evidence for the protective role of Nrf2 in male fertility.

One-Step Self-Assembly of Multifunctional DNA Nanohydrogels: An Enhanced and Harmless Strategy for Guiding Combined Antitumor Therapy

DNA nanostructure-based drug delivery system (DDS) has become an advanced therapeutic strategy for cancer because of its unsurpassed editability, intrinsic biodegradability, and tunable multifunctionality. An intelligent DNA nanosystem integrating targeting, immunostimulation, and chemotherapy was constructed based on unmethylated cytosine-phosphate-guanine oligonucleotides (CpG ODNs) DNA nanohydrogels (CpG-MUC1-hydrogel). By facile one-step self-assembly, the cross-shaped DNAs (C-DNAs) assembled from pH-responsive I-motif sequences and targeted MUC1 aptamer-immunoadjuvant CpG-fused sequences (CpG-MUC1) were integrated into DNA nanohydrogels with controllable size by the hybridization of DNA linkers. Subsequently, DOX was successively intercalated into the base pairs of CpG-MUC1-hydrogel, resulting in CpG-MUC1-hydrogel/Dox that would disassemble and release DOX and CpGs at acidic conditions. After MUC1-mediated internalization, CpG-MUC1-hydrogel/Dox dissociated in the endo/lysosomes and induced favorable apoptosis of tumor cells. Afterward, liberated CpGs triggered vast cytokine secretion from immune cells which elicited potent immune response against malignancy. Notably, CpG-MUC1-hydrogel induced an apoptosis effect on MCF-7 cells via significantly increasing the Bax/Bcl₂ ratios and a higher level of tumor necrosis factor (TNF-α) on RAW264.7 cells than naked CpGs. Our results demonstrated that self-assembled CpG-MUC1-hydrogel represented an attractive DDS for precise delivery, potent immunostimulating activity, and considerable combination efficiency with few adverse effects, which is expected to make breakthroughs in clinical translation.

Drug repurposing for breast cancer therapy: Old weapon for new battle

Despite tremendous resources being invested in prevention and treatment, breast cancer remains a leading cause of cancer deaths in women globally. The available treatment modalities are very costly and produces severe side effects. Drug repurposing that relate to new uses for old drugs has emerged as a novel approach for drug development. Repositioning of old, clinically approved, off patent non-cancer drugs with known targets, into newer indication is like using old weapons for new battle. The advances in genomics, proteomics and information computational biology has facilitated the process of drug repurposing. Repositioning approach not only fastens the process of drug development but also offers more effective, cheaper, safer drugs with lesser/known side effects. During the last decade, drugs such as alkylating agents, anthracyclins, antimetabolite, CDK4/6 inhibitor, aromatase inhibitor, mTOR inhibitor and mitotic inhibitors has been repositioned for breast cancer treatment. The repositioned drugs have been successfully used for the treatment of most aggressive triple negative breast cancer. The literature review suggest that serendipity plays a major role in the drug development. This article describes the comprehensive overview of the current scenario of drug repurposing for the breast cancer treatment. The strategies as well as several examples of repurposed drugs are provided. The challenges associated with drug repurposing are discussed.

Polymeric Mesoporous Silica Nanoparticles for Enhanced Delivery of 5-Fluorouracil In Vitro

There is a need for the improvement of conventional cancer treatment strategies by incorporation of targeted and non-invasive procedures aimed to reduce side-effects, drug resistance, and recurrent metastases. The anti-cancer drug, 5-fluorouracil (5-FU), is linked to a variety of induced-systemic toxicities due to its lack of specificity and potent administration regimens, necessitating the development of delivery vehicles that can enhance its therapeutic potential, while minimizing associated side-effects. Polymeric mesoporous silica nanoparticles (MSNs) have gained popularity as delivery vehicles due to their high loading capacities, biocompatibility, and good pharmacokinetics. MSNs produced in this study were functionalized with the biocompatible polymers, chitosan, and poly(ethylene)glycol to produce monodisperse NPs of 36-65 nm, with a large surface area of 710.36 m2/g, large pore volume, diameter spanning 9.8 nm, and a favorable zeta potential allowing for stability and enhanced uptake of 5-FU. Significant drug loading (0.15-0.18 mg5FU/mgmsn), controlled release profiles (15-65%) over 72 hours, and cell specific cytotoxicity in cancer cells (Caco-2, MCF-7, and HeLa) with reduced cell viability (≥50%) over the non-cancer (HEK293) cells were established. Overall, these 5FU-MSN formulations have been shown to be safe and effective delivery systems in vitro, with potential for in vivo applications.

Neuroprotective Effects of Ferruginol, Jatrophone, and Junicedric Acid Against Amyloid-β Injury in Hippocampal Neurons

Soluble amyloid-β (Aβ) oligomers have been recognized as early neurotoxic intermediates with a key role in the synaptic dysfunction observed in Alzheimer's disease (AD). Aβ oligomers block hippocampal long-term potentiation (LTP) and impair rodent spatial memory. Additionally, the presence of Aβ oligomers is associated with imbalanced intracellular calcium levels and apoptosis in neurons. In this context, we evaluated the effects of three diterpenes (ferruginol, jatrophone, and junicedric acid) that are found in medicinal plants and have several forms of biological activity. The intracellular calcium levels in hippocampal neurons increased in the presence of ferruginol, jatrophone, and junicedric acid, a result that was consistent with the observed increase in CA1 synaptic transmission in mouse hippocampal slices. Additionally, assays using Aβ peptide demonstrated that diterpenes, particularly ferruginol, restore LTP and reduce apoptosis. Recovery of the Aβ oligomer-induced loss of the synaptic proteins PSD-95, synapsin, VGlut, and NMDA receptor subunit 2A was observed in mouse hippocampal slices treated with junicedric acid. This cascade of events may be associated with the regulation of kinases, e.g., protein kinase C (PKC) and calcium/calmodulin-dependent protein kinase II (CaMKII), in addition to the activation of the canonical Wnt signaling pathway and could thus provide protection against Aβ oligomers, which trigger synaptic dysfunction. Our results suggest a potential neuroprotective role for diterpenes against the Aβ oligomers-induced neurodegenerative alterations, which make them interesting molecules to be further studied in the context of AD.

LncRNA H19 interacted with miR-130a-3p and miR-17-5p to modify radio-resistance and chemo-sensitivity of cardiac carcinoma cells

The current investigation explored the synthetic contribution of lncRNA H19, miR-130a-3p, and miR-17-5p to radio-resistance and chemo-sensitivity of cardiac cancer cells. Totally 284 human cardiac cancer tissues were gathered, and they have been pathologically diagnosed. The cardiac cancer cells were isolated with utilization of the mechanic method. Moreover, cisplatin, adriamycin, mitomycin, and 5-fluorouracil were designated as the chemotherapies, and single-dose X-rays were managed as the radiotherapy for cardiac cancer cells. We also performed luciferase reporter gene assay to verify the targeted relationship between H19 and miR-130a-3p, as well as between H19 and miR-17-5p. Finally, mice models were established to examine the functions of H19, miR-130a-3p, and miR-17-5p on the development of cardiac cancer. The study results indicated that H19, miR-130a-3p, and miR-17-5p expressions within cardiac cancer tissues were significantly beyond those within adjacent nontumor tissues (P < 0.05), and H19 expression was positively correlated with both miR-130a-3p (r_s  = 0.43) and miR-17-5p (r_s  = 0.49) expressions. The half maximal inhibitory concentrations (IC50) of cisplatin, adriamycin, mitomycin, and 5-fluorouracil for cardiac cancer cells were, respectively, determined as 2.01 μg/mL, 8.35 μg/mL, 24.44 μg/mL, and 166.42 μg/mL. The overexpressed H19, miR-130a-3p, and miR-17-5p appeared to improve the survival rate and viability of cardiac cancer cells that were exposed to chemotherapies and X-rays (all P < 0.05). It was also drawn from luciferase reporter gene assay that H19 could directly target miR-130a-3p and miR-17-5p, thereby modifying the sensitivity of cardiac cancer cells to drugs and X-rays (P < 0.05). Finally, the mice models also produced larger tumor size and higher tumor weight, when H19, miR-130a-3p, or miR-17-5p expressions were up-regulated within them (P < 0.05). In conclusion, H19 could act on miR-130a-3p or miR-17-5p to alter the radio- and chemo-sensitivities of cardiac cancer cells, helping to improve the radio-/chemotherapies for cardiac cancer.

Sequencing of anthracyclines and taxanes in neoadjuvant and adjuvant therapy for early breast cancer

BACKGROUND

Anthracyclines and taxanes are chemotherapeutic agents widely used in a sequential regimen in the adjuvant and neoadjuvant treatment of early breast cancer to reduce the risk of cancer recurrence. Standard practice is to administer anthracycline-based chemotherapy followed by a taxane. Anthracyclines tend to be administered first as they were established before taxanes for treatment of early breast cancer.

OBJECTIVES

To assess whether the sequence in which anthracyclines and taxanes are administered affects outcomes for people with early breast cancer receiving adjuvant or neoadjuvant therapy.

SEARCH METHODS

We searched Cochrane Breast Cancer's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov on 1 February 2018.

SELECTION CRITERIA

Randomised controlled trials comparing administering a taxane prior to an anthracycline with taxane following anthracycline to people with early breast cancer receiving chemotherapy. The studies needed to have reported on at least one of our outcomes of interest, which included overall survival, disease-free survival, pathological response, treatment adherence, toxicity and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data, assessed risk of bias and quality of the evidence. The primary outcome measure was overall survival. Secondary outcomes included disease-free survival, pathological response (in the neoadjuvant setting only), adverse events, treatment adherence and quality of life. For time-to-event outcomes of overall survival and disease-free survival, we derived hazard ratios (HRs) with 95% confidence intervals (CI) where possible. For dichotomous outcomes of pathological complete response, treatment adherence and adverse events, we reported the treatment effect as a risk ratio (RR) with 95% CI where possible. We used GRADE to assess the certainty of the evidence separately for the neoadjuvant and adjuvant settings.

MAIN RESULTS

There were 1415 participants in five neoadjuvant studies and 280 participants in four adjuvant studies involving five treatment comparisons. Four of the five neoadjuvant studies collected data for the primary outcome (overall survival) and two studies had data available; one of the four adjuvant studies collected overall survival data.The neoadjuvant studies suggested that the administration of taxanes first probably resulted in little to no difference in overall survival (HR 0.80, 95% CI 0.60 to 1.08; 947 participants; 2 studies; moderate-certainty evidence) and disease-free survival (HR 0.84, 95% CI 0.65 to 1.09; 828 participants; 1 study; moderate-certainty evidence). Administration of taxanes first also resulted in little to no difference in pathological complete response (absence of cancer in the breast and axilla: RR 1.15, 95% CI 0.96 to 1.38; 1280 participants; 4 studies; high-certainty evidence). However, there appeared to be a trend in favour of taxanes first. Studies reported treatment adherence using a range of measures. Administration of taxanes first probably did not increase the likelihood of requiring dose reductions compared to administration of anthracyclines first (RR 0.81, 95% CI 0.59 to 1.11; 280 participants; 1 study; moderate-certainty evidence). There was probably little to no difference in the risk of grade 3/4 neutropenia (RR 1.25, 95% CI 0.86 to 1.82; 280 participants, 1 study; moderate-certainty evidence) or grade 3/4 neurotoxicity (RR 0.95, 95% CI 0.55 to 1.65; 1108 participants; 2 studies; low-certainty evidence) when taxanes were given first. There were no data on quality of life.Only one adjuvant study collected data on overall survival and disease-free survival but did not report data. Administration of taxanes first reduced the risk of grade 3/4 neutropenia (RR 0.62, 95% CI 0.40 to 0.97; 279 participants; 4 studies, 5 treatment comparisons; high-certainty evidence) and appeared to result in little to no difference in grade 3/4 neurotoxicity (RR 0.78, 95% CI 0.25 to 2.46; 162 participants; 3 studies; low-certainty evidence). There was probably little to no difference in the proportions experiencing dose delays when taxanes are given first compared to anthracyclines given first (RR 0.76, 95% CI 0.52 to 1.12; 238 participants; 3 studies, 4 treatment comparisons; moderate-certainty evidence). One study reported on quality of life and indicated that scores (using the Functional Assessment of Cancer Therapy - Breast Cancer (FACT-B) validated questionnaire) were similar in both groups though did not provide numerical data.

AUTHORS' CONCLUSIONS

In the neoadjuvant setting, there is high- to low-certainty evidence of equivalent outcomes for the sequence in which taxanes are delivered. In the adjuvant setting, none of the studies reported on overall survival or disease-free survival. In most institutions, standard practice would be to deliver anthracycline followed by taxane, and currently available data do not support a change in this practice. We wait for the full-text publication of a relevant neoadjuvant study for women with HER2-negative breast cancer for inclusion in an update of this review.

TRPM2 channel-mediated regulation of autophagy maintains mitochondrial function and promotes gastric cancer cell survival via the JNK-signaling pathway

A lack of effective treatment is one of the main factors contributing to gastric cancer-related death. Discovering effective targets and understanding their underlying anti-cancer mechanism are key to achieving the best response to treatment and to limiting side effects. Although recent studies have shown that the cation channel transient receptor potential melastatin-2 (TRPM2) is crucial for cancer cell survival, the exact mechanism remains unclear, limiting its therapeutic potential. Here, using molecular and functional assays, we investigated the role of TRPM2 in survival of gastric cancer cells. Our results indicated that TRPM2 knockdown in AGS and MKN-45 cells decreases cell proliferation and enhances apoptosis. We also observed that the TRPM2 knockdown impairs mitochondrial metabolism, indicated by a decrease in basal and maximal mitochondrial oxygen consumption rates and ATP production. These mitochondrial defects coincided with a decrease in autophagy and mitophagy, indicated by reduced levels of autophagy- and mitophagy-associated proteins (i.e. ATGs, LC3A/B II, and BNIP3). Moreover, we found that TRPM2 modulates autophagy through a c-Jun N-terminal kinase (JNK)-dependent and mechanistic target of rapamycin-independent pathway. We conclude that in the absence of TRPM2, down-regulation of the JNK-signaling pathway impairs autophagy, ultimately causing the accumulation of damaged mitochondria and death of gastric cancer cells. Of note, by inhibiting cell proliferation and promoting apoptosis, the TRPM2 down-regulation enhanced the efficacy of paclitaxel and doxorubicin in gastric cancer cells. Collectively, we provide compelling evidence that TRPM2 inhibition may benefit therapeutic approaches for managing gastric cancer.

Antitumor activity of Notch‑1 inhibition in human colorectal carcinoma cells

This study investigated the roles of Notch-1 in colorectal carcinoma, to assess the mechanisms. The expression of Notch-1 and its ligand-Jagged1 was detected in human colorectal carcinoma, colorectal adenoma, paracancerous tissue and normal colorectal tissue by immunohistochemistry. Colorectal carcinoma cell lines were utilized to confirm the expression of Notch-1 in colorectal carcinoma cells. Lentiviral-encoding Notch-1-siRNA, as well as Notch-1 inhibitor was employed to silence Notch-1 expression and to inhibit Notch-1 activity in HT29 cells, respectively. As evidenced, Notch-1 and Jagged1 were highly expressed in colorectal carcinoma and colorectal adenoma tissues, compared with those in paracancerous tissue and normal colorectal tissue. However, the expression of Notch-1 and Jagged1 was comparable in colorectal carcinoma and colorectal adenoma tissues, and in paracancerous and normal colorectal tissues. After screening colorectal carcinoma cell lines, Notch-1 was extensively expressed in COLO 205, HT29, SW480 and SW1116 cells, but slightly expressed in LoVo cells. Subsequently, HT29 cell line was selected to investigate the roles of Notch-1 in tumor cell growth and apoptosis. Lenti-viral encoding Notch-1 siRNA significantly decreased Notch-1 expression, inhibited cell growth, arrested the cell cycle at G1 phase and promoted apoptosis. These effects were further confirmed by the Notch-1 inhibitor DAPT. Additionally, we evidenced that Notch-1 silence promoted P21 and PUMA expression in HT29 cells. Taken together, Notch-1 is an oncogene in colorectal carcinoma and the inhibition of Notch-1 could delay the cell growth and promote apoptosis in colorectal cancer.

Downregulation of Caspase 8 in a group of Iranian breast cancer patients - A pilot study

PURPOSE

It is now well known that evading apoptosis, as a cancer hallmark, can lead to tumour initiation, progression and metastasis. As a result of genome wide association studies, an initiator protease in this pathway, caspase 8 (CASP8), has been found to be an important gene regarding breast cancer susceptibility. The alterations of the expression of this gene have been reported in breast cancer cell lines. Given that in previous studies expression analysis of this gene had only been done in breast cancer cell lines, in this study we aimed to evaluate the expression of this gene in breast cancer tissues versus adjacent normal tissues, using real-time quantitative method.

METHODS

Caspase 8 mRNA expression was quantified using comparative RT-qPCR in 27 fresh frozen breast tumours and 27 adjacent normal tissues. Moreover, relationship between the expression changes of CASP8 in tumour tissue and various clinical and pathological features were evaluated in an Iranian population.

RESULTS

The present study showed that expression of CASP8 was significantly reduced in tumour tissues compared to neighbouring normal tissues (p = .004). CASP8 expression was significantly correlated with the status of hormone receptors (ER and PR).

CONCLUSION

To the best of our knowledge, this study is the first report on reduced expression of CASP8 in breast cancer versus adjacent normal tissues. Our data support previous results obtained from cell lines and therefore highlights the seminal role of the induction of CASP8 expression, as a novel therapeutic approach, in order to sensitize tumour cells to apoptotic stimuli.

Association of O6-Methylguanine-DNA Methyltransferase Protein Expression With Postoperative Prognosis and Adjuvant Chemotherapeutic Benefits Among Patients With Stage II or III Gastric Cancer

IMPORTANCE

Loss of O6-methylguanine-DNA methyltransferase (MGMT) protein expression has been reported in several malignant tumors and predicts dismal survival outcomes. In gastric cancer, existing studies on this topic are limited and the association between MGMT and fluorouracil-based adjuvant chemotherapy remains obscure.

OBJECTIVE

To investigate the postoperative prognostic significance of MGMT in patients with resectable gastric cancer and its responsiveness to fluorouracil-based adjuvant chemotherapy.

DESIGN, SETTING, AND PARTICIPANTS

This study recruited 445 consecutive patients with resectable gastric cancer who underwent radical gastrectomy between August 1, 2007, and December 30, 2008, at Zhongshan Hospital at Fudan University in Shanghai, China. Patients were randomly divided into a discovery data set (n = 200) and a validation data set (n = 245), and the range of follow-up time was from 2 to 76 months for the discovery group and 2 to 79 months for the validation group. The immunoreactivity for MGMT in cancer cells was reviewed under a light microscope by 2 pathologists who were blinded to the clinicopathological data. The association of MGMT expression with clinicopathological characteristics and measures and prognosis was inspected. Data and specimens were collected from patients from the date of surgery to April 25, 2014. Data analysis took place from May 9, 2016, to July 15, 2016.

MAIN OUTCOMES AND MEASURES

Estimates of overall survival on the basis of MGMT expression and hazard ratio (HR) for estimates of overall mortality risk.

RESULTS

Of the 445 patients included in the study, 315 (70.8%) were men, and the mean (SD) age of all patients was 60 (12) years. Positive expression of MGMT indicated better overall survival for patients with stage II or III gastric cancer in both the discovery data set (HR, 0.52; 95% CI, 0.32-0.84; P = .003) and the validation data set (HR, 0.63; 95% CI, 0.43-0.93; P = .01). Multivariate analysis identified MGMT expression and TNM stage as 2 independent prognostic factors for overall survival. In stage II disease, the benefit from fluorouracil-based adjuvant chemotherapy was superior among MGMT-positive patients (HR, 0.35; 95% CI, 0.13-0.95; P = .007 for interaction) compared with MGMT-negative patients.

CONCLUSIONS AND RELEVANCE

Positive expression of MGMT in gastric cancer was identified as an independent, favorable prognostic factor. Incorporating MGMT expression into the current TNM staging system could lead to better prognostic accuracy. These findings should be confirmed within the framework of randomized clinical trials associated with genomic DNA sequencing studies.

GALNT6 Stabilizes GRP78 Protein by O-glycosylation and Enhances its Activity to Suppress Apoptosis Under Stress Condition

We previously reported that overexpression of an O-type glycosyltransferase, GALNT6 (polypeptide N-acetylgalactosaminyltransferase 6) played critical roles in mammary carcinogenesis. To further investigate the biological function of GALNT6, we screened a substrate protein(s) of GALNT6 using a VVA (Vicia villosa agglutinin) lectin (specific to GalNAc-Ser/Thr) pull-down method followed by mass spectrometry analysis. Here we report GRP78 (glucose-regulated protein 78, also known as HSPA5, heat shock 70 kDa protein 5), which is highly expressed in cancer cells and indicated to play important roles in various cellular processes including ER (endoplasmic reticulum) stress and autophagy, as a novel substrate of GALNT6. We found that GALNT6-induced O-glycosylation is critical for the stability of GRP78, its subcellular localization in ER, and its anti-apoptotic function. Furthermore, we demonstrated that overexpression of GRP78 could be important for Golgi-to-ER relocation of GALNT6. Collectively, our study revealed biological significances of O-glycosylation of GRP78 protein, which might play significant roles in the survival of cancer cells, and thus provided a new insight in cancer cell death and useful information for development of anti-cancer treatment targeting the GALNT6-GRP78 pathway.

Glycoprotein 130 is associated with adverse postoperative clinical outcomes of patients with late-stage non-metastatic gastric cancer

The interaction of glycoprotein 130 (gp130) with the cytokines of Interleukin-6 (IL-6) family has proved to play a crucial part in several cancers. Our current study is designed to discover the clinical prognostic significance of gp130 in non-metastatic gastric cancer. We examined intratumoral gp130 expression in retrospectively enrolled 370 gastric cancer patients who underwent radical gastrectomy with standard D2 lymphadenectomy at Zhongshan Hospital of Fudan University during 2007 and 2008 by immunohistochemical staining. The expression of gp130 was significantly correlated with T classification, N classification and TNM stage (P = 0.003, P < 0.001 and P < 0.001, respectively; T, N, TNM refers to Tumor Invasion, Regional lymph node metastasis and Tumor Node Metastasis, respectively). Elevated intratumoral gp130 expression implied unfavourable overall survival (OS) (P < 0.001) and disease-free survival (DFS) (P < 0.001), respectively. Furthermore, among TNM II and III gp130-high patients, those who were treated with 5-fluorouracil (5-FU) based adjuvant chemotherapy had better OS (P < 0.001). The generated nomogram performed well in predicting the 3- and 5-year OS of gastric cancer patients. The incorporation of gp130 into contemporary TNM staging system would be of great significance to improve the current individual risk stratification. These findings contribute to better clinical management for those patients who would benefit from adjuvant chemotherapy.

CITED2 in breast carcinoma as a potent prognostic predictor associated with proliferation, migration and chemoresistance

CITED2 (Cbp/p300‐interacting transactivator, with Glu/Asp‐rich carboxy‐terminal domain, 2) is a member of the CITED family and is involved in various cellular functions during development and differentiation. Mounting evidence suggests the importance of CITED in the progression of human malignancies, but the significance of CITED2 protein has not yet been examined in breast carcinoma. Therefore, in the present study, we examined the clinical significance and the biological functions of CITED2 in breast carcinoma by immunohistochemistry and in vitro study. CITED2 immunoreactivity was detected in breast carcinoma tissues, and it was significantly higher compared to those in morphologically normal mammary glands. CITED2 immunoreactivity was significantly associated with stage, pathological T factor, lymph node metastasis, histological grade, HER2 and Ki‐67, and inversely correlated with estrogen receptor. Moreover, the immunohistochemical CITED2 status was significantly associated with increased incidence of recurrence and breast cancer‐specific death of the breast cancer patients, and multivariate analyses demonstrated CITED2 status as an independent worse prognostic factor for disease‐free and breast cancer‐specific survival. Subsequent in vitro experiments showed that CITED2 expression significantly increased proliferation activity and migration property in MCF‐7and S KBR‐3 breast carcinoma cells. Moreover, CITED2 caused chemoresistance to epirubicin and 5‐fluorouracil, but not paclitaxel, in these cells, and it inhibited p53 accumulation after 5‐fluorouracil treatment in MCF‐7 cells. These results suggest that CITED2 plays important roles in the progression and chemoresistance of breast carcinoma and that CITED2 status is a potent prognostic factor in breast cancer patients.

Altering bioelectricity on inhibition of human breast cancer cells

Background

Membrane depolarization is associated with breast cancer. Depolarization-activated voltage-gated ion channels are directly implicated in the initiation, proliferation, and metastasis of breast cancer.

Methods

In this study, the role of voltage-gated potassium and calcium ion channel modulation was explored in two different invasive ductal human carcinoma cell lines, MDA-MB-231 (triple-negative) and MCF7 (estrogen-receptor-positive).

Results

Resting membrane potential is more depolarized in MCF7 and MDA-MB-231 cells compared to normal human mammary epithelial cells. Increasing extracellular potassium concentration up to 50 mM depolarized membrane potential and greatly increased cell growth. Tetraethylammonium (TEA), a non-specific blocker of voltage-gated potassium channels, stimulated growth of MCF7 cells (control group grew by 201 %, 1 mM TEA group grew 376 %). Depolarization-induced calcium influx was hypothesized as a requirement for growth of human breast cancer. Removing calcium from culture medium stopped growth of MDA and MCF7 cells, leading to cell death after 1 week. Verapamil, a blocker of voltage-gated calcium channels clinically used in treating hypertension and coronary disease, inhibited growth of MDA cells at low concentration (10–20 μM) by 73 and 92 % after 1 and 2 days, respectively. At high concentration (100 μM), verapamil killed >90 % of MDA and MCF7 cells after 1 day. Immunoblotting experiments demonstrated that an increased expression of caspase-3, critical in apoptosis signaling, positively correlated with verapamil concentration in MDA cells. In MCF7, caspase-9 expression is increased in response to verapamil.

Conclusions

Our results support our hypotheses that membrane depolarization and depolarization-induced calcium influx stimulate proliferation of human breast cancer cells, independently of cancer subtypes. The underlying mechanism of verapamil-induced cell death involves different caspases in MCF7 and MDA-MB-231. These data suggest that voltage-gated potassium and calcium channels may be putative targets for pharmaceutical remediation in human invasive ductal carcinomas.

5-Fluorouracil chemotherapy upregulates cytokines and alters hippocampal dendritic complexity in aged mice

5-Fluorouracil (5-Fu) is commonly used chemotherapy drug, but it can lead to the impairment of cognitive function. The pathogenesis of this injury is unknown but may involve modifications to dendritic structure and/or alterations in dendritic spine density and morphology. Dendritic spines are sites of excitatory synaptic transmission and changes in spine structure and dendrite morphology are thought to represent a morphological correlate of altered brain functions associated with hippocampal dependent learning and memory. A total of 28 one-year-old C57BL6/J male mice were used in this study; 14 mice received 5-Fu treatment and 14 were given saline injections. One month post treatment, 14 cytokines were measured at the same time Golgi samples were taken. 8 analytes were significantly elevated in mice treated with 5-Fu. 5-Fu significantly compromised the dendritic architecture and reduced spine density throughout the hippocampal tri-synaptic network. The present data provide the evidence that 5-Fu has deleterious effects on mature neurons associated with hippocampal learning and memory.

EGFR tyrosine kinase inhibitors promote pro-caspase-8 dimerization that sensitizes cancer cells to DNA-damaging therapy

The combination of time and order-dependent chemotherapeutic strategies has demonstrated enhanced efficacy in killing cancer cells while minimizing adverse effects. However, the precise mechanism remains elusive. Our results showed that pre-treatment of MCF-7 and MDA-MB-468 cells with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib or lapatinib significantly enhanced the cytotoxic effects of DNA-damaging agents compared to coadministration of the EGFR inhibitor and DNA-damaging agent. Sequential application of erlotinib and doxorubicin increased activated caspase-8 by promoting pro-caspase-8 homodimerization and autocatalytical cleavage, whereas coadministration did not. We found that EGFR inhibitors promoted pro-caspase-8 homodimerization by inhibiting ERK pathway signaling, while doxorubicin promoted it. Our data highlight that ERK has the potential to inhibit the formation of pro-caspase-8 homodimers by phosphorylating pro-caspase-8 at S387. In conclusion, the pretreatment of EGFR tyrosine kinase inhibitors promote pro-caspase-8 dimerization that sensitizes cancer cells to DNA-damaging agents. Our findings provide rationale for novel strategies for the implementation of combined targeted and cytotoxic chemotherapy within a new framework of time and order-dependent therapy.

New 3'-O-aromatic acyl-5-fluoro-2'-deoxyuridine derivatives as potential anticancer agents

New aromatic and aliphatic 3'-O-acyl-5-fluoro-2'-deoxyuridine derivatives were synthesized and evaluated as candidates for prodrugs against various cancer cell lines. As the most promising candidate for antimalignant therapeutics was found a dual-acting acyl derivative 7h, which apparently released not only the known anticancer nucleoside, 5-fluoro-2'-deoxyuridine (FdU), but also an additional active metabolite, acetylsalicylic acid, reinforcing thus therapeutic effect of FdU. Promising therapeutic indices showed also some aromatic dicarboxylic acids derivatives decorated with FdU esters (11 and 12).

Conserved molecular mechanisms underlying the effects of small molecule xenobiotic chemotherapeutics on cells

For proper determination of the apoptotic potential of chemoxenobiotics in synergism, it is important to understand the modes, levels and character of interactions of chemoxenobiotics with cells in the context of predicted conserved biophysical properties. Chemoxenobiotic structures are studied with respect to atom distribution over molecular space, the predicted overall octanol-to-water partition coefficient (Log OWPC; unitless) and molecular size viz a viz van der Waals diameter (vdWD). The Log OWPC-to-vdWD (nm^-1 ) parameter is determined, and where applicable, hydrophilic interacting moiety/core-to-vdWD (nm^-1 ) and lipophilic incorporating hydrophobic moiety/core-to-vdWD (nm^-1 ) parameters of their part-structures are determined. The cellular and sub-cellular level interactions of the spectrum of xenobiotic chemotherapies have been characterized, for which a classification system has been developed based on predicted conserved biophysical properties with respect to the mode of chemotherapeutic effect. The findings of this study are applicable towards improving the effectiveness of existing combination chemotherapy regimens and the predictive accuracy of personalized cancer treatment algorithms as well as towards the selection of appropriate novel xenobiotics with the potential to be potent chemotherapeutics for dendrimer nanoparticle-based effective transvascular delivery.

Major Contributions towards Finding a Cure for Cancer through Chemotherapy: A Historical Review

The history of cancer chemotherapy is as old as cancer itself. With the increase in the complexities of cancer and the development of resistance towards existing anticancer agents, increased attention is now being paid to the advancement of chemotherapy. Some chemotherapeutic agents were discovered by accident or trial-and-error methods while others were found to be useful for neoplasia when they were being evaluated for some other purpose. Broadly, these agents have been classified as alkylating agents, antimetabolites, platinum compounds, antitumor antibiotics and natural products. Hormones and compounds interfering with hormone metabolism are widely used in cancer treatment, besides monoclonal antibodies and small molecules targeting angiogenesis. In this review an attempt is made to discuss the major breakthroughs that have shaped the course of cancer chemotherapy, helping to decrease the mortality as well as lessen the suffering of patients.

Implementation of validated pharmacodynamic assays in multiple laboratories: challenges, successes, and limitations

There is a "life cycle" of pharmacodynamic (PD) biomarker assays that guides the development and clinical implementation in our laboratories. The well-recognized elements of analytical assay validation and demonstration of fitness-for-purpose of the biomarker, specimen collection, handling, and assay methods are only a part of the required activities. Assay transfer across laboratories and testing on actual human clinical specimens are vital for understanding assay performance and robustness. In our experience, this patient specimen-centered approach has required assay method modifications, some unexpected, but which were critical to successful implementation in clinical trials. In addition, dispersing assays throughout the National Cancer Institute's clinical trials network has required the development of calibrator and control materials as well as formal training courses for smooth implementation. One measure of success of this approach has been that a number of the assays developed at NCI's Frederick National Laboratory have ultimately reached the stage of commercialization, enabling wide accessibility of the PD biomarker assays by the research community. See all articles in this ccr focus section, "Progress in pharmacodynamic endpoints."

Biomaterials based nano-applications of Aloe vera and its perspective: a review

In modern biomedical researches, theAloe veraextract has been engaged in the synthesis of various micro and nanoformulations based smart structures, which increased its competence in wound healing, tissue engineering and drug delivery applications.

Radiofrequency heat-enhanced chemotherapy for breast cancer: towards interventional molecular image-guided chemotherapy

Breast cancer is the most common malignancy in women worldwide. Recent developments in minimally invasive interventional radiology techniques have significantly improved breast cancer treatment. This study aimed to develop a novel technique for the local management of breast cancers using radiofrequency heat (RFH). We performed both in vitro experiments using human breast cancer cells and in vivo validation in xenograft animal models with magnetic resonance imaging (MRI) and pathological correlation to investigate the feasibility of our approach. Four treatment groups, including (1) no treatment (control), (2) RFH-only, (3) chemo (doxorubicin)-only, and (4) combination therapy with both doxorubicin and RFH, were conducted in each experiment. In vitro combination therapy significantly decreased breast cancer cell proliferation while increased their apoptosis index compared to the other three groups. MRI demonstrated a significant tumor size reduction in animals treated with combination therapy compared to those receiving other treatments in vivo. Such result was further confirmed by pathological examination. In conclusion, our findings suggests that RFH can enhance the therapeutic efficiency of doxorubicin on breast cancers, thus establishing the basis for future development of interventional molecular image-guided local chemotherapy for breast malignancies.

DNA methylation in thyroid tumorigenesis

Thyroid cancer is the most common endocrine cancer with 1,690 deaths each year. There are four main types of which the papillary and follicular types together account for >90% followed by medullary cancers with 3% to 5% and anaplastic carcinomas making up <3%. Epigenetic events of DNA hypermethylation are emerging as promising molecular targets for cancer detection. Our immediate and long term goal is to identify DNA methylation markers for early detection of thyroid cancer. This pilot study comprised of 21 patients to include 11 papillary thyroid cancers (PTC), 2 follicular thyroid cancers (FTC), 5 normal thyroid cases, and 3 hyperthyroid cases. Aberrant promoter methylation was examined in 24 tumor suppressor genes using the methylation specific multiplex ligation-dependent probe amplification (MS-MLPA) assay and in the NIS gene using methylation-specific PCR (MSP). The frequently methylated genes were CASP8 (17/21), RASSF1 (16/21) and NIS (9/21). In the normal samples, CASP8, RASSF1 and NIS were methylated in 5/5, 4/5 and 1/5 respectively. In the hyperthyroid samples, CASP8, RASSF1 and NIS were methylated in 3/3, 2/3 and 1/3 respectively. In the thyroid cancers, CASP8, RASSF1, and NIS were methylated in 9/13, 10/13, and 7/13 respectively. CASP8, RASSF1 and NIS were also methylated in concurrently present normal thyroid tissue in 3/11, 4/11 and 3/11 matched thyroid cancer cases (matched for presence of both normal thyroid tissue and thyroid cancer), respectively. Our data suggests that aberrant methylation of CASP8, RASSF1, and NIS maybe an early change in thyroid tumorigenesis regardless of cell type.

Selective antitumor effect of neural stem cells expressing cytosine deaminase and interferon-beta against ductal breast cancer cells in cellular and xenograft models

Due to their inherent tumor-tropic properties, genetically engineered stem cells may be advantageous for gene therapy treatment of various human cancers, including brain, liver, ovarian, and prostate malignancies. In this study, we employed human neural stem cells (HB1.F3; hNSCs) transduced with genes expressing Escherichia coli cytosine deaminase (HB1.F3.CD) and human interferon-beta (HB1.F3.CD.IFN-β) as a treatment strategy for ductal breast cancer. CD can convert the prodrug 5-fluorocytosine (5-FC) to its active chemotherapeutic form, 5-fluorouracil (5-FU), which induces a tumor-killing effect through DNA synthesis inhibition. IFN-β also strongly inhibits tumor growth by the apoptotic process. RT-PCR confirmed that HB1.F3.CD cells expressed CD and HB1.F3.CD.IFN-β cells expressed both CD and IFN-β. A modified transwell migration assay showed that HB1.F3.CD and HB1.F3.CD.IFN-β cells selectively migrated toward MCF-7 and MDA-MB-231 human breast cancer cells. In hNSC-breast cancer co-cultures the viability of breast cancer cells which were significantly reduced by HB1.F3.CD or HB1.F3.CD.IFN-β cells in the presence of 5-FC. The tumor inhibitory effect was greater with the HB1.F3.CD.IFN-β cells, indicating an additional effect of IFN-β to 5-FU. In addition, the tumor-tropic properties of these hNSCs were found to be attributed to chemoattractant molecules secreted by breast cancer cells, including stem cell factor (SCF), c-kit, vascular endothelial growth factor (VEGF), and VEGF receptor 2. An in vivo assay performed using MDA-MB-231/luc breast cancer mammary fat pad xenografts in immunodeficient mice resulted in 50% reduced tumor growth and increased long-term survival in HB1.F3.CD and HB1.F3.CD.IFN-β plus 5-FC treated mice relative to controls. Our results suggest that hNSCs genetically modified to express CD and/or IFN-β genes can be used as a novel targeted cancer gene therapy.

The involvement of Helicobacter pylori thioredoxin-1 in gastric carcinogenesis

Helicobacter pylori infection is related to the development of gastric diseases. Various virulence factors are responsible for the pathogenic mechanisms of H. pylori infection. Our previous studies using two-dimensional gel electrophoresis showed that H. pylori thioredoxin-1 (Trx1) is overexpressed in gastric carcinomas. Here, we examined whether H. pylori Trx1 is a novel virulence factor associated with gastric tumorigenesis. We found that Trx1 expression in H. pylori isolated from gastric cancer tissues was significantly higher than that from tissues exhibiting gastritis. In the gastric epithelial cell line GES-1, infection of H. pylori with high Trx1 expression significantly induced cell apoptosis, decreased the expression of cyclin D1 and upregulated p21. However, in the gastric cancer cell line BGC823, high Trx1 expression in H. pylori significantly increased cell proliferation, and upregulated cyclin D1. The effects on cell lines were confirmed using the H. pylori Trx1-knockout mutant strain. Our observations indicate that high Trx1 expression in H. pylori is associated with gastric carcinogenesis. In H. pylori, Trx1 likely participates in the pathogenesis of gastric cancer and H. pylori expressing high levels of Trx1 would be expected to be highly pathogenic in gastric diseases in China.

Dracorhodin perchlorate induced human breast cancer MCF-7 apoptosis through mitochondrial pathways

OBJECTIVE

Dracorhodin perchlorate (DP) was a synthetic analogue of the antimicrobial anthocyanin red pigment dracorhodin. It was reported that DP could induce apoptosis in human prostate cancer, human gastric tumor cells and human melanoma, but the cytotoxic effect of DP on human breast cancer was not investigated. This study would investigate whether DP was a candidate chemical of anti-human breast cancer.

METHODS

The MTT assay reflected the number of viable cells through measuring the activity of cellular enzymes. Phase contrast microscopy visualized cell morphology. Fluorescence microscopy detected nuclear fragmentation after Hoechst 33258 staining. Flowcytometric analysis of Annexin V-PI staining and Rodamine 123 staining was used to detect cell apoptosis and mitochondrial membrane potential (MMP). Real time PCR detected mRNA level. Western blot examined protein expression.

RESULTS

DP dose and time-dependently inhibited the growth of MCF-7 cells. DP inhibited MCF-7 cell growth through apoptosis. DP regulated the expression of Bcl-2 and Bax, which were mitochondrial pathway proteins, to decrease MMP, and DP promoted the transcription of Bax and inhibited Bcl-2. Apoptosis-inducing factor (AIF) and cytochrome c which localized in mitochondrial in physiological condition were released into cytoplasm when MMP was decreased. DP activated caspase-9, which was the downstream of mitochondrial pathway. Therefore DP decreased MMP to release AIF and cytochrome c into cytoplasm, further activating caspase 9, lastly led to apoptosis.

CONCLUSION

Therefore DP was a candidate for anti-breast cancer, DP induced apoptosis of MCF-7 through mitochondrial pathway.

BMSCs reduce rat granulosa cell apoptosis induced by cisplatin and perimenopause

Background

The objective of this study was to evaluate the effect of bone marrow mesenchymal stem cells (BMSCs) on the apoptosis of granulosa cells (GCs) in rats.

BMSCs and GCs were isolated from rats. GCs were separated into one of the following three groups: an untreated control group (control), a cisplatin (5 mg/L) treatment group (cisplatin), and group co-cultured with BMSCs and treated with cisplatin (BMSC). GC apoptosis was analyzed by annexin V staining and real-time PCR analysis for apoptosis-related genes. The effect of BMSCs was also determined in 9 to 10 month-old perimenopausal rats that were separated into the following groups: saline control, BMSC transplantation (1–2 × 10⁶ cells), and estrogen treatment (0.158 mg/kg/d) groups. A young group consisting of 3 to 4 month-old rats that were treated with saline was also evaluated as a control. After 1 and 3 months, GC apoptosis was evaluated by TUNEL analysis.

Results

Cisplatin increased GC apoptosis from 0.59% to 13.04% in the control and cisplatin treatment groups, respectively, which was significantly reduced upon co-culture with BMSCs to 4.84%. Cisplatin treatment increased p21 and bax and decreased c-myc mRNA expression, which was reversed upon co-culture with BMSCs. As compared to young rats, increased apoptosis was observed in the perimenopausal rats (P < 0.001). After 3 months, the apoptosis rate in the BMSC group was significantly lower than that of the control group (P = 0.007).

Conclusions

BMSC therapy may protect against GC apoptosis induced by cisplatin and perimenopause. Further studies are necessary to evaluate therapeutic efficacy of BMSCs.

Effects of 5-fluorouracil and gemcitabine on a breast cancer cell line (MCF-7) via the JAK/STAT pathway

Aberrant activation of the JAK/STAT pathway may predispose to malignancy as a consequence of the deregulation of cell proliferation, differentiation or apoptosis such as in cancer of the blood, head and neck, and breast. In our study we aimed to investigate the effects of 5-fluorouracil (5-FU) and gemcitabine on a breast cancer cell line (MCF-7 cells) via the JAK/STAT pathway. Distribution of JAK1, JAK2, JAK3 and STAT2, STAT3, STAT4, STAT5 were evaluated on MCF-7 cells following gemcitabine and 5-FU treatment and in the absence of drug treatment by an indirect immunohistochemical method. It was observed that JAK1, JAK3, STAT5 and particularly STAT2 activation were more effective than the other JAK/STATs in breast cancer progression. Following treatment with 5-FU, JAK1 and STAT5 immunoreactivities were decreased in MCF-7 cells in comparison with both gemcitabine-treated and non-treated groups. These results suggest that the JAK/STAT pathway plays an important role in breast cancer pathogenesis and may be more affected after 5-FU treatment rather than gemcitabine. Drugs which block STAT5 may provide a novel therapeutic approach for the treatment of breast cancer.

CCL2/CCR2 chemokine signaling coordinates survival and motility of breast cancer cells through Smad3 protein- and p42/44 mitogen-activated protein kinase (MAPK)-dependent mechanisms

Increased cell motility and survival are important hallmarks of metastatic tumor cells. However, the mechanisms that regulate the interplay between these cellular processes remain poorly understood. In these studies, we demonstrate that CCL2, a chemokine well known for regulating immune cell migration, plays an important role in signaling to breast cancer cells. We report that in a panel of mouse and human breast cancer cell lines CCL2 enhanced cell migration and survival associated with increased phosphorylation of Smad3 and p42/44MAPK proteins. The G protein-coupled receptor CCR2 was found to be elevated in breast cancers, correlating with CCL2 expression. RNA interference of CCR2 expression in breast cancer cells significantly inhibited CCL2-induced migration, survival, and phosphorylation of Smad3 and p42/44MAPK proteins. Disruption of Smad3 expression in mammary carcinoma cells blocked CCL2-induced cell survival and migration and partially reduced p42/44MAPK phosphorylation. Ablation of MAPK phosphorylation in Smad3-deficient cells with the MEK inhibitor U0126 further reduced cell survival but not migration. These data indicate that Smad3 signaling through MEK-p42/44MAPK regulates CCL2-induced cell motility and survival, whereas CCL2 induction of MEK-p42/44MAPK signaling independent of Smad3 functions as an alternative mechanism for cell survival. Furthermore, we show that CCL2-induced Smad3 signaling through MEK-p42/44MAPK regulates expression and activity of Rho GTPase to mediate CCL2-induced breast cancer cell motility and survival. With these studies, we characterize an important role for CCL2/CCR2 chemokine signaling in regulating the intrinsic relationships between breast cancer cell motility and survival with implications on the metastatic process.

Development and evaluation of 5-fluorouracil loaded chitin nanogels for treatment of skin cancer

This study focuses on development and evaluation of 5-fluorouracil (5-FU) loaded chitin nanogels (FCNGs). It formed good, stable aqueous dispersion with spherical particles in 120-140 nm size range and showed pH responsive swelling and drug release. The FCNGs showed toxicity on melanoma (A375) in a concentration range of 0.4-2.0mg/mL, but less toxicity toward human dermal fibroblast (HDF) cells by MTT assay. Confocal analysis revealed uptake of FCNGs by both cells. From skin permeation experiments, FCNGs showed almost same steady state flux as that of control 5-FU but the retention in the deeper layers of skin was found to be 4-5 times more from FCNGs. Histopathological evaluation revealed loosening of the horny layer of epidermis by interaction of cationically charged chitin, with no observed signs of inflammation and so FCNGs can be a good option for treatment of skin cancers.

Therapeutic potential of stem cells expressing suicide genes that selectively target human breast cancer cells: evidence that they exert tumoricidal effects via tumor tropism (review)

Breast cancer is the most prevalent cancer in women worldwide and is classified into ductal and lobular carcinoma. Breast cancer as well as lobular carcinoma is associated with various risk factors such as gender, age, female hormone exposure, ethnicity, family history and genetic risk factor-associated genes. Genes associated with a high risk of developing breast cancer include BRCA1, BRCA2, p53, PTEN, CHEK2 and ATM. Surgery, chemotherapy, radiotherapy and hormone therapy are used to treat breast cancer but these therapies, except for surgery, have many side-effects such as alopecia, anesthesia, diarrhea and arthralgia. Gene-directed enzyme/prodrug therapy (GEPT) or suicide gene therapy, may improve the therapeutic efficacy of conventional cancer radiotherapy and chemotherapy without side-effects. GEPT most often involves the use of a viral vector to deliver a gene not found in mammalian cells and that produces enzymes which can convert a relatively non-toxic prodrug into a toxic agent. Examples of these systems include cytosine deaminase/5-fluorocytosine (CD/5-FC), carboxyl esterase/irinotecan (CE/CPT-11), and thymidine kinase/ganciclovir (TK/GCV). Recently, therapies based on genetically engineered stem cells (GESTECs) using a GEPT system have received a great deal of attention for their clinical and therapeutic potential to treat breast cancer. In this review, we discuss the potential of GESTECs via tumor tropism effects and therapeutic efficacy against several different types of cancer cells. GESTECs represent a useful tool for treating breast cancer without inducing injuries associated with conventional therapeutic modalities.

Aloe vera induced biomimetic assemblage of nucleobase into nanosized particles

AIM

Biomimetic nano-assembly formation offers a convenient and bio friendly approach to fabricate complex structures from simple components with sub-nanometer precision. Recently, biomimetic (employing microorganism/plants) synthesis of metal and inorganic materials nano-particles has emerged as a simple and viable strategy. In the present study, we have extended biological synthesis of nano-particles to organic molecules, namely the anticancer agent 5-fluorouracil (5-FU), using Aloe vera leaf extract.

METHODOLOGY

The 5-FU nano- particles synthesized by using Aloe vera leaf extract were characterized by UV, FT-IR and fluorescence spectroscopic techniques. The size and shape of the synthesized nanoparticles were determined by TEM, while crystalline nature of 5-FU particles was established by X-ray diffraction study. The cytotoxic effects of 5-FU nanoparticles were assessed against HT-29 and Caco-2 (human adenocarcinoma colorectal) cell lines.

RESULTS

Transmission electron microscopy and atomic force microscopic techniques confirmed nano-size of the synthesized particles. Importantly, the nano-assembled 5-FU retained its anticancer action against various cancerous cell lines.

CONCLUSION

In the present study, we have explored the potential of biomimetic synthesis of nanoparticles employing organic molecules with the hope that such developments will be helpful to introduce novel nano-particle formulations that will not only be more effective but would also be devoid of nano-particle associated putative toxicity constraints.