Change in expression of apoptosis genes after hyperthermia, chemotherapy and radiotherapy in human colon cancer transplanted into nude mice

Nanoparticle-Mediated Hyperthermia and Cytotoxicity Mechanisms in Cancer

Hyperthermia has the potential to damage cancerous tissue by increasing the body temperature. However, targeting cancer cells whilst protecting the surrounding tissues is often challenging, especially when implemented in clinical practice. In this direction, there are data showing that the combination of nanotechnology and hyperthermia offers more successful penetration of nanoparticles in the tumor environment, thus allowing targeted hyperthermia in the region of interest. At the same time, unlike radiotherapy, the use of non-ionizing radiation makes hyperthermia an attractive therapeutic option. This review summarizes the existing literature regarding the use of hyperthermia and nanoparticles in cancer, with a focus on nanoparticle-induced cytotoxicity mechanisms.

Combination Therapy of Radiation and Hyperthermia, Focusing on the Synergistic Anti-Cancer Effects and Research Trends

Despite significant therapeutic advances, the toxicity of conventional therapies remains a major obstacle to their application. Radiation therapy (RT) is an important component of cancer treatment. Therapeutic hyperthermia (HT) can be defined as the local heating of a tumor to 40-44 °C. Both RT and HT have the advantage of being able to induce and regulate oxidative stress. Here, we discuss the effects and mechanisms of RT and HT based on experimental research investigations and summarize the results by separating them into three phases. Phase (1): RT + HT is effective and does not provide clear mechanisms; phase (2): RT + HT induces apoptosis via oxygenation, DNA damage, and cell cycle arrest; phase (3): RT + HT improves immunological responses and activates immune cells. Overall, RT + HT is an effective cancer modality complementary to conventional therapy and stimulates the immune response, which has the potential to improve cancer treatments, including immunotherapy, in the future.

Fluorescence-based thermometry for precise estimation of nanoparticle laser-induced heating in cancerous cells at nanoscale

Photothermal therapy (PTT) has attracted increasing interest as a complementary method to be used alongside conventional therapies. Despite a great number of studies in this field, only a few have explored how temperatures affect the outcome of the PTT at nanoscale. In this work, we study the necrosis/apoptosis process of cancerous cells that occurs during PTT, using a combination of local laser heating and nanoscale fluorescence thermometry techniques. The temperature distribution within a whole cell was evaluated using fluorescence lifetime imaging microscopy during laser-induced hyperthermia. For this, gold nanorods were utilized as nanoheaters. The local near-infrared laser illumination produces a temperature gradient across the cells, which is precisely measured by nanoscale thermometry. This allows one to optimize the PTT conditions by varying concentration of gold nanorods associated with cells and laser power density. During the PTT procedure, such an approach enables an accurate determination of the percentages of apoptotic and necrotic cells using 2D and 3D models. According to the performed cell experiments, the influence of temperature increase during the PTT on cell death mechanisms has been verified and determined. Our investigations can improve the understanding of the PTT mechanisms and increase its therapeutic efficiency while avoiding any side effects.

Potential anti-tumor activity of 13.56 MHz alternating magnetic hyperthermia and chemotherapy on the induction of apoptosis in human colon cancer cell lines HT29 and HCT116 by up-regulation of Bax, cleaved caspase 3&9, and cleaved PARP proteins

Background

The purpose of the present study was to evaluate the efficacy of chemo-magnetic hyperthermia (MH), a combination of alternating magnetic field (AMF) and superparamagnetic nanoparticles (SPIONs) coated with Polyethylene glycol-Poly(butyl acrylate)-Polyethylene glycol (PEG-PBA-PEG) carrying 5-Fluorouracil (5-Fu), at inducing apoptosis in the human cancer cell lines HT29 and HCT116. This process can be mediated by alterations in the expression of apoptotic effector proteins, including Bax, Bcl-2, cleaved caspase 3&9, and cleaved PARP, which are involved in the intrinsic pathway of apoptosis. For this purpose, the cells were cultured as monolayers. Then both cell lines were treated with 5-Fu/magnetic nanoparticles and magnetic hyperthermia. Finally, the effect of treatment on cancer cells was determined by Western blot analysis and flow cytometry.

Results

Our results showed that combined chemo-magnetic thermotherapy significantly increased the apoptosis in colon cancer cells compared to chemotherapy or hyperthermia alone (P < 0.05). Up-regulation of Bax, cleaved caspase 3&9, and cleaved PARP proteins was indicative of apoptosis induction in cancer cells, which are involved in the intrinsic pathway of apoptosis.

Conclusions

This study demonstrates that localized hyperthermia was able to significantly trigger the 5-Fu release and inhibit cell viability, which, due to the synchronization of hyperthermia and chemotherapy, exacerbated the damage of cancer cells.

Graphical Abstract

Combined Hyperthermia and Radiation Therapy for Treatment of Hepatocellular Carcinoma

Background:

There is no doubt that hyperthermia is one of the powerful radiosensitizers. Finding a proper mechanism working in hyperthermia/radiation combination is still pronounced challenge.

Objectives:

This study is focusing on the anti-cancer activities (anti-proliferative, anti-angiogenic and antiapoptotic) of thermoradiotherapy.

Materials and Methods:

Liver cancer cell line (HepG2) was treated by 37^oC, 40^oC and 43^oC hyperthermia degrees combined with three radiation doses (2 Gy, 4 Gy and 8 Gy) for 24, 48 and 72 hrs. Cell viability, apoptotic/necrotic cell screening, apoptotic (BAX and FasL) and antiapoptotic (BCL-2 and GRP78) genes, and pro-angiogenic mediators [vascular endothelial- (VEGF) and Platelet derived-growth factors (PDGF) ware investigated.

Results:

Our data showed that 40^oC temperature combined with 4 Gy radiation gives a significant decrease (p<0.05) in cell viability. Maximum cytotoxicity was reported 48 hr post-treatment followed by slight restoration of cell viability after 72 hr. Compared with untreated cells, only 5% of viable cells with a high percentage of apoptotic (31%) and necrotic (63%) cells were demonstrated in 40^oC/4 Gy/48 hr group. Expression of pro-apoptotic genes (BAX and FasL) were increased after hyperthermia with apparent elevation in 40^oC/4 Gy/48 hr group coincides with moderate expression of antiapoptotic BCL-2 and GRP78 genes. A significant reduction (p<0.001; p<0.05) in VEGF and PDGF levels; respectively was shown at 40^oC/4 Gy/48 hr group.

Conclusions:

This pilot study proposed 40^oC mild temperature hyperthermia as a favorable hyperthermal condition with 4 Gy radiotherapy in HCC treatment. A further research has to be performed considering an application of more than one session of radiothermal therapy at 40^oC/4 Gy for total abrogation of cancer cells.

Immunogenic Effect of Hyperthermia on Enhancing Radiotherapeutic Efficacy

Hyperthermia is a cancer treatment where tumor tissue is heated to around 40 °C. Hyperthermia shows both cancer cell cytotoxicity and immune response stimulation via immune cell activation. Immunogenic responses encompass the innate and adaptive immune systems, involving the activation of macrophages, natural killer cells, dendritic cells, and T cells. Moreover, hyperthermia is commonly used in combination with different treatment modalities, such as radiotherapy and chemotherapy, for better clinical outcomes. In this review, we will focus on hyperthermia-induced immunogenic effects and molecular events to improve radiotherapy efficacy. The beneficial potential of integrating radiotherapy with hyperthermia is also discussed.

Intraperitoneal chemotherapy for locally advanced gastric cancer to prevent and treat peritoneal carcinomatosis

Gastric cancer (GC) is one of the leading causes of cancer death in both sexes in the world. The overall survival (OS) of GC patients is still unsatisfactory. The peritoneal dissemination is the most common type of recurrence in advanced GC. The rationale for administering chemotherapeutic drugs directly into peritoneal cavity is supported by the relative transport barrier that is formed by the tissue surrounding the peritoneal space. Intraperitoneal (IP) chemotherapy with taxanes is safe and feasible. Further randomized phase III clinical trials are needed to validate IP chemotherapy with taxanes for peritoneal carcinomatosis (PC) from GC. Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) used as prophylaxis against peritoneal recurrence in patients with high risk GC is safe, significantly improves the survival and reduces the risk of peritoneal recurrence. A drug delivery system with anticancer drugs seem to be have a pharmacokinetic advantage but further randomized clinical trials are needed to validate its effect.

EMMPRIN, SP1 and microRNA-27a mediate physcion 8-O-β-glucopyranoside-induced apoptosis in osteosarcoma cells

Physcion 8-O-β-glucopyranoside (PG), the main active ingredient of Rumex japonicus, induces apoptosis and causes cell cycle arrest in human lung cancer cells. However, its anti-tumor effects are not fully understood. In this study, we explored the mechanisms underlying PG induced apoptosis in the osteosarcoma cell line MG-63. Our results showed that PG exerted anti-proliferative effects and induced apoptosis in MG-63 cells via the intrinsic mitochondrial pathway, accompanied by loss of mitochondrial membrane potential (MMP) and cytochrome C release from the mitochondria. In addition, physcion treatment significantly inhibited extracellular matrix metalloproteinase inducer (EMMPRIN) expression in MG-63 cells, in a dose-dependent manner; meanwhile, EMMPRIN protein overexpression markedly reduced PG-induced apoptosis. Moreover, our findings suggested that the modulatory effects of PG on EMMPRIN were due, at least in part, to regulation of an ROS-miR-27a/ZBTB10-Sp1 transcription factor pathway.

Growth Hormone Protects the Intestine Preserving Radiotherapy Efficacy on Tumors: A Short-Term Study

The efficacy of radiotherapy on tumors is hampered by its devastating adverse effects on healthy tissue, particularly that of the gastrointestinal tract. These effects cause acute symptoms that are so disruptive to patients that they can lead to interruption of the radiotherapy program. These adverse effects could limit the intensity of radiation received by the patient, resulting in a sublethal dose to the tumor, thus increasing the risk of tumor resistance. The lack of an effective treatment to protect the bowel during radiation therapy to allow higher radiation doses that are lethal to the tumor has become a barrier to implementing effective therapy. In this study, we present a comparative analysis of both intestinal and tumor tissue in regard to the efficacy and the preventive impact of a short-term growth hormone (GH) treatment in tumor-bearing rats as a protective agent during radiotherapy. Our data show that the exogenous administration of GH improved intestinal recovery after radiation treatment while preserving the therapeutic effect against the tumor. GH significantly increased proliferation in the irradiated intestine but not in the irradiated tumors, as assessed by Positron Emission Tomography and the proliferative markers Ki67, cyclin D3, and Proliferating Cell Nuclear Antigen. This proliferative effect was consistent with a significant increase in irradiated intestinal villi and crypt length. Furthermore, GH significantly decreased caspase-3 activity in the intestine, whereas GH did not produce this effect in the irradiated tumors. In conclusion, short-term GH treatment protects the bowel, inducing proliferation while reducing apoptosis in healthy intestinal tissue and preserving radiotherapy efficacy on tumors.

GNRs@SiO₂-FA in combination with radiotherapy induces the apoptosis of HepG2 cells by modulating the expression of apoptosis-related proteins

The aim of the present study was to examine the apoptosis of the hepatocellular carcinoma cell line, HepG2, induced by treatment with folic acid-conjugated silica-coated gold nanorods (GNRs@SiO₂-FA) in combination with radiotherapy, and to determine the involvement of apoptosis-related proteins. An MTT colorimetric assay was used to assess the biocompatibility of GNRs@SiO₂-FA. The distribution of GNRs@SiO₂-FA into the cells was observed using transmission electron microscopy (TEM). HepG2 cells cultured in vitro were divided into the following 4 groups: i)the control group (untreated), ii) the GNRs@SiO₂-FA group, iii) the radiotherapy group (iodine 125 seeds) and iv) the combination group (treated with GNRs@SiO₂-FA and iodine 125 seeds) groups. The apoptosis of the HepG2 cells was detected by flow cytometry. The concentration range of <40 µg/ml GNRs@SiO₂-FA was found to be safe for the biological activity of the HepG2 cells. GNRs@SiO₂-FA entered the cytoplasm through endocytosis. The apoptotic rates of the HepG2 cells were higher in the GNRs@SiO₂-FA and radiotherapy groups than in the control group (P<0.05). The apoptotic rate was also significantly higher in the combination group than the GNRs@SiO₂-FA and radiotherapy groups (P<0.05). Taken together, these findings demonstrate that the combination of GNRs@SiO₂-FA and radiotherapy more effectively induces the apoptosis of HepG2 cells. These apoptotic effects are achieved by increasing the protein expression of Bax and caspase-3, and inhibiting the protein expression of Bcl-2 and Ki-67. The combination of GNRs@SiO₂-FA and radiotherapy may thus prove to be a new approach in the treatment of primary liver cancer.

Magnetic thermoablation stimuli alter BCL2 and FGF-R1 but not HSP70 expression profiles in BT474 breast tumors

Magnetically induced heating of magnetic nanoparticles (MNP) in an alternating magnetic field (AMF) is a promising minimal invasive tool for localized tumor treatment that eradicates tumor cells by applying thermal stress. While temperatures between 42°C and 45°C induce apoptosis and sensitize the cells for chemo- and radiation therapies when applied for at least 30 minutes, temperatures above 50°C, so-called thermoablative temperatures, rapidly induce irreversible cell damage resulting in necrosis. Since only little is known concerning the protein expression of anti-apoptotic B-cell lymphoma 2 (BCL2), fibroblast growth factor receptor 1 (FGF-R1), and heat shock protein (HSP70) after short-time magnetic thermoablative tumor treatment, these relevant tumor proteins were investigated by immunohistochemistry (IHC) in a human BT474 breast cancer mouse xenograft model. In the investigated sample groups, the application of thermoablative temperatures (<2 minutes) led to a downregulation of BCL2 and FGF-R1 on the protein level while the level of HSP70 remained unchanged. Coincidently, the tumor tissue was damaged by heat, resulting in large apoptotic and necrotic areas in regions with high MNP concentration. Taken together, thermoablative heating induced via magnetic methods can reduce the expression of tumor-related proteins and locally inactivate tumor tissue, leading to a prospectively reduced tumorigenicity of cancerous tissues. The presented data allow a deeper insight into the molecular mechanisms in relation to magnetic thermoablative tumor treatments with the aim of further improvements.

Indocyanine green targeted micelles with improved stability for near-infrared image-guided photothermal tumor therapy

Aim: Indocyanine green (ICG) is a promising near-infrared (NIR) dye for tumor imaging and photothermal therapy; however, the poor stability and lack of targeting limit its application. In this study, ICG was encapsulated into folate-conjugated poly(2-ethyl-2-oxazoline)-b-poly(ε-caprolactone) micelles to overcome these problems. Materials & methods: ICG-loaded micelles were prepared by solvent evaporation method. Cell uptake and in vitro photothermal cytotoxicity were evaluated on KB cells. In vivo NIR imaging and photothermal therapy were conducted on KB tumor-bearing mice. Results: ICG-loaded micelles with favorable sizes and stable NIR optical properties were successfully prepared. These micelles could target to KB tumors and enabled high-resolution NIR imaging. Moreover, they could effectively convert the absorbed NIR laser energy into heat, resulting in significant tumor damage and inhibition. Conclusion: This novel micellar system, integrating stable NIR properties, excellent tumor targeting and photothermal capability, showed great potential in tumor imaging and therapy.

Intracellular Acidosis Promotes Mitochondrial Apoptosis Pathway: Role of EMMPRIN Down-regulation via Specific Single-chain Fv Intrabody

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a human leukocyte surface molecule that is enriched on the surface of many cancer cells, and it plays an important role in proliferation and metastasis. In this study, we utilized the chimeric adenoviral vector Ad5/F35 carrying gene encoding scFv against EMMPRIN (scFv-M6-1B9) to down-regulate EMMPRIN cell surface expression and investigated programmed cell death response in colorectal cancer (CRC) cell, Caco-2. The scFv-M6-1B9 intrabody exhibits robust activity in reducing EMMPRIN cell surface expression. This approach led to the inducing of apoptosis, which was relative to the increasing of apoptotic bodies in sub-G1 peak, phosphatidylserine externalization, as well as TUNEL-positive cells. In addition, real-time RT-PCR and western blotting analysis indicated that apoptosis was enhanced through the mitochondrial pathway, a marked reduction of Bcl-2, leading to the translocation of cytochrome c and also the dramatic activation of caspase-3. Moreover, carcinoembryonic antigen (CEA), a tumor marker for CRC, was found to have significantly diminished in both secreted protein and mRNA levels. In conclusion, these findings suggest that EMMPRIN down-regulation by scFv-M6-1B9 intrabody has great potential in enhancing the efficacy of apoptosis induction through the mitochondrial pathway and in effecting a decline in the CEA level. Thus, its benefits could be applied to project the future prospects for targeted gene therapy and therapeutic application in monitoring colorectal cancer.

Native disorder mediates binding of dynein to NudE and dynactin

In the present paper, I report the molecular overlap of the linkage of three essential protein complexes that co-ordinate the formation of the mitotic spindle. These proteins are dynein, a large motor complex that moves machinery inside cells, and two of its regulators: a protein complex called dynactin, a dynein activator, and a protein called NudE whose depletion in mice produces a small brain and mental retardation. What is intriguing about the dynein-dynactin-NudE interplay is that dynactin and NudE bind to a common segment of dynein that is intrinsically disordered. Elucidating differences in their binding modes may explain how one regulator can be selected over the other even when both are present in the same cellular compartment. These results not only have a far-reaching impact on our understanding of processes essential for the formation and orientation of the spindle, but also offer a novel role for protein disorder in controlling cellular processes, and highlight the advantages of NMR spectroscopy in elucidating atomic-level characterization of extremely complex dynamic cellular assemblies.

A new model of rectal cancer with regional lymph node metastasis allowing in vivo evaluation by imaging biomarkers

OBJECT

The work is aimed to develop a murine model of rectal cancer, which could be used to monitor lymph node metastasis development by magnetic resonance imaging (MRI) and optical imaging (OI) techniques.

SUBJECTS AND METHODS

Ht-29 cancer cells were directly injected into the submucosal layer of the rectum of athymic nude mice using trans-anal rectal cancer cell injection (TARCI). Thirty-six mice were inoculated with 10×10(5) cells and five mice were treated with sterile phosphate buffer solution. One to 4 weeks after cell injection, tumor growth was evaluated in vivo using T2-weighted MRI at 4.7T. A further group of animal (n=6) treated with ht-29_luc cells, with the same protocol, was monitored by optical imaging. In both groups, the presence of the primary tumor and of lymph nodes metastasis was confirmed by histology.

RESULTS

In all animals, primary tumors were detectable by MRI, 1 week from TARCI. After 4 weeks primary tumors showed a mean longitudinal diameter of about 2cm. All animals developed regional lymph node metastases. Others organs (e.g. lung or liver) were not affected. In fat-suppressed, T2-weighted MRI, lymph nodes appeared as small areas characterized by hyper-intense signal compared to muscle. OI permitted evaluation of the primary tumor growth in perineal region.

CONCLUSIONS

TARCI of ht-29 cells into the rectum of nude mice is a feasible way to obtain a easily reproducible model of regional lymph node metastases could be monitored by magnetic resonance and optical imaging techniques.

Analysis of thermochemotherapy-induced apoptosis and the protein expressions of Bcl-2 and Bax in maxillofacial squamous cell carcinomas

The aim of this study is to investigate the relationship between thermochemotherapy-induced apoptosis and the expressions of the Bcl-2 and Bax proteins in maxillofacial squamous cell carcinomas. Fifteen patients with maxillofacial squamous cell carcinomas were treated with microwave hyperthermia (43 °C for 40 min) following the intravenous injection of pingyangmycin (Bleomycin A5 Hydrochloride for Injection) (8 mg). Subsequently, the tumors were surgically resected. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling method was used to assess the apoptosis in the carcinoma cells, and immunohistochemistry was performed using the streptavidin-peroxidase method to determine the expression levels of the Bcl-2 and Bax proteins, and quantitative analysis was employed. The number of apoptotic cells increased markedly (P < 0.001). The protein expression of Bcl-2 was downregulated (P < 0.001), while that of Bax was markedly upregulated (P < 0.001). Thermochemotherapy induces apoptosis in maxillofacial squamous cell carcinoma cells by downregulating the protein expression of Bcl-2 and upregulating that of Bax.

Overexpression of S100A4 in human cancer cell lines resistant to methotrexate

Background

Methotrexate is a chemotherapeutic drug that is used in therapy of a wide variety of cancers. The efficiency of treatment with this drug is compromised by the appearance of resistance. Combination treatments of MTX with other drugs that could modulate the expression of genes involved in MTX resistance would be an adequate strategy to prevent the development of this resistance.

Methods

The differential expression pattern between sensitive and MTX-resistant cells was determined by whole human genome microarrays and analyzed with the GeneSpring GX software package. A global comparison of all the studied cell lines was performed in order to find out differentially expressed genes in the majority of the MTX-resistant cells. S100A4 mRNA and protein levels were determined by RT-Real-Time PCR and Western blot, respectively. Functional validations of S100A4 were performed either by transfection of an expression vector for S100A4 or a siRNA against S100A4. Transfection of an expression vector encoding for β-catenin was used to inquire for the possible transcriptional regulation of S100A4 through the Wnt pathway.

Results

S100A4 is overexpressed in five out of the seven MTX-resistant cell lines studied. Ectopic overexpression of this gene in HT29 sensitive cells augmented both the intracellular and extracellular S100A4 protein levels and caused desensitization toward MTX. siRNA against S100A4 decreased the levels of this protein and caused a chemosensitization in combined treatments with MTX. β-catenin overexpression experiments support a possible involvement of the Wnt signaling pathway in S100A4 transcriptional regulation in HT29 cells.

Conclusions

S100A4 is overexpressed in many MTX-resistant cells. S100A4 overexpression decreases the sensitivity of HT29 colon cancer human cells to MTX, whereas its knockdown causes chemosensitization toward MTX. Both approaches highlight a role for S100A4 in MTX resistance.