Hyperthermia combined with intra-thoracic chemotherapy and radiotherapy for malignant pleural mesothelioma

The future opportunities and remaining challenges in the application of nanoparticle-mediated hyperthermia combined with chemo-radiotherapy in cancer

A pivotal cause of death in the modern world, cancer is an insidious pathology that should be diagnosed at an early stage for successful treatment. Development of therapeutic interventions with minimal invasiveness and high efficacy that can discriminate between tumor and normal cells is of particular interest to the clinical science, as they can enhance patient survival. Nanoparticles are an invaluable asset that can be adopted for development of such diagnostic and therapeutic modalities, since they come in very small sizes with modifiable surface, are highly safe and stable, and can be synthesized in a controlled fashion. To date, different nanoparticles have been incorporated into numerous modalities such as tumor-targeted therapy, thermal therapy, chemotherapy, and radiotherapy. This review article seeks to deliver a brief account of recent advances in research and application of nanoparticles in hyperthermia-based cancer therapies. The most recent investigations are summarized to highlight the latest advances in the development of combined thermo-chemo-radiotherapy, along with the challenges associated with the application of nanoparticles in cancer therapy. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Effect of hyperthermic intrathoracic chemotherapy on the malignant pleural mesothelioma: a systematic review and meta-analysis

Surgery-based multimodality therapies have been used to control the malignant effusion and its recurrence in malignant pleural mesothelioma (MPM). Hyperthermic intrathoracic chemotherapy (HITHOC) has been used in the treatment of malignant pleural mesothelioma, but the results were controversial. The aim of the current study was, therefore, to conduct a systematic review and meta-analysis on the effect of HITHOC on MPM therapy. After thorough searching of online databases, total 21 articles were included into qualitative systematic review and 5 of them were used to conduct qualitative meta-analysis. It was found that most of HITHOC was used in combination of surgical resection including extrapleural pneumonectomy or pleurectomy/decortication. Patients who received HITHOC had significantly longer median survival length compared to the patients without HITHOC (Hedges's g = 0.384 ± 0.105, 95% CI: 0.178∼0.591, P < 0.001). In addition, HITHOC as palliative therapy was favored (Hedges's g = 0.591 ± 0.201, 95% CI: 0.196∼0.967, P < 0.001) in terms of recurrence free interval. The findings of the current study suggested that HITHOC is one of the safe and effective therapies in prolonging patients' median survival time and extending recurrence free interval.

BAG3 protects against hyperthermic stress by modulating NF-κB and ERK activities in human retinoblastoma cells

PURPOSE

BCL2-associated athanogene 3 (BAG3), a co-chaperone of HSP70, is a cytoprotective and anti-apoptotic protein that acts against various stresses, including heat stress. Here, we examined the effect of BAG3 on the sensitivity of human retinoblastoma cells to hyperthermia (HT).

METHODS

We examined the effects of BAG3 knockdown on the sensitivity of Y79 and WERI-Rb-1cells to HT (44 °C, 1 h) by evaluating apoptosis and cell proliferation using western blotting, real-time quantitative PCR (qPCR), flow cytometry, and a WST-8 assay kit. Furthermore, we examined the effects of activating nuclear factor-kappa B (NF-κB) and extracellular signal-regulated kinase (ERK) using western blotting and real time qPCR.

RESULTS

HT induced considerable apoptosis along with the activation of caspase-3 and chromatin condensation. The sensitivity of Y79 and WERI-Rb-1 cells to HT was significantly enhanced by BAG3 knockdown. Compared to HT alone, the combination of BAG3 knockdown and HT reduced phosphorylation of the inhibitors of kappa B α (IκBα) and p65, a subunit of NF-κB, and degraded IκB kinase γ (IKKγ) during the recovery period after HT. Furthermore, BAG3 knockdown increased the HT-induced phosphorylation of ERK after HT treatment, and the ERK inhibitor U0126 significantly improved the viability of the cells treated with a combination of BAG3 knockdown and HT.

CONCLUSIONS

The silencing of BAG3 seems to enhance the effects of HT, at least in part, by maintaining HT-induced inactivity of NF-κB and the phosphorylation of ERK. These findings indicate that BAG3 may be a potential molecular target for modifying the outcomes of HT in retinoblastoma.

A seven-year disease-free survivor of malignant pleural mesothelioma treated with hyperthermia and chemotherapy: a case report

Introduction

Malignant pleural mesothelioma was once a rare finding but its incidence is increasing worldwide, most likely because of widespread exposure to asbestos. Although complete surgical resection is considered the only curative treatment, the results of surgery have shown a median survival time of only one year. In inoperable cases, chemotherapy, radiotherapy, and a combination of both have been considered as palliative therapy. Therefore, outcomes for inoperable cases have been poor. Here, we report the case of a long-term survivor treated with hyperthermia and chemotherapy.

Case presentation

A 61-year-old Japanese man with a performance status of 1 due to chest pain was referred to our hospital. He had a history of asbestos exposure for approximately five years. A computed tomography scan showed diffuse extensive right pleural thickening with small nodular lesions, and video-assisted thoracoscopy revealed tumor invasion of the ipsilateral chest wall muscles. The histopathologic findings were consistent with a diagnosis of malignant pleural mesothelioma (sarcomatoid type). The tumor was diagnosed as being stage cT3N0M0. Our patient refused any invasive therapies including surgery and radiotherapy, and was therefore treated with hyperthermia and systemic chemotherapy with agents such as cisplatin and irinotecan. He underwent three hyperthermia sessions and a single course of chemotherapy without any severe complications. One month after treatment, a follow-up computed tomography scan showed no definitive abnormality in the thoracic space. Our patient has subsequently survived without any evident disease for more than seven years.

Conclusions

The combination of hyperthermia and chemotherapy may be a novel and safe therapeutic option for malignant pleural mesothelioma, and can be considered for patients ineligible for radical treatment. Further clinical studies of the combination of hyperthermia and chemotherapy are needed to confirm the effects of this treatment on malignant pleural mesothelioma.

[Guidelines of the European Respiratory Society and the European Society of Thoracic Surgeons for the management of malignant pleural mesothelioma]

恶性胸膜间皮瘤（malignant pleural mesothelioma, MPM）是一种罕见肿瘤，但发病率正逐渐上升，且预后较差。2008年，欧洲呼吸学会（European Respiratory Society, ERS）和欧洲胸外科医师学会（European Society of Thoracic Surgeons, ESTS）特别工作组召集各方专家计划制定MPM诊治经验及更新指南。

为了使MPM得到及时准确的诊断，专家推荐对患者实施胸腔镜检查，有手术禁忌和胸腔粘连的病例除外。约10%的病例采用标准染色方法无法获得满意的结果。因此我们推荐在胸膜活检的基础上，采用特异性免疫组化标志物。由于目前缺乏一个统一的、切实有效的分期系统，我们推荐应用最新的TNM分期，并且提出三个阶段的治疗前评估。在MPM的治疗中，患者的体力状态评分和组织亚型是目前唯一的、具有重要临床价值的预后因素。在临床试验中，应对其它潜在因素进行初步探讨并予以报道。MPM对化疗高度耐受，仅有少数患者可接受根治性手术。本文对新的治疗方法和策略进行了综述。

目前由于最佳综合治疗的资料有限，适合采用多种方案联合治疗策略的患者应被纳入专业机构的前瞻性试验中。

Radiation therapy options for malignant pleural mesothelioma

The role of radiation therapy (RT) in the curative treatment of malignant pleural mesothelioma remains undefined. No data clearly support treatment of unresected mesothelioma with definitive RT. Early reports showed that RT was associated with unacceptable toxicity, but recent limited data suggest that treatment with intensity-modulated radiation therapy (IMRT) may be tolerable. Adjuvant RT after pleurectomy is also challenging, and similarly, no clear efficacy has been demonstrated. Some approaches, such as IMRT to the circumferential pleural envelope, appear feasible, but the fact that this approach does not address the disease in the fissures is problematic. The best setting in which to deliver RT is after extrapleural pneumonectomy, but the large and irregular target volume and multiple and adjacent sensitive normal structures make this complex. The Memorial Sloan-Kettering Cancer Center matched photon/electron technique is associated with acceptable efficacy and toxicity, but is limited in that it does not achieve complete coverage of the target volume to the prescription dose. The best dosimetry is achieved using IMRT, and this approach is the most promising to date. However, the toxicity profile can be severe, and the relevant predictive factors for complications are not fully understood. For these reasons, physicians should exercise caution, and IMRT after extrapleural pneumonectomy is probably best offered only by experienced teams or on protocol until further data have been gathered. New techniques such as helical tomotherapy and/or IMRT with the addition of electrons may also have a role in future treatment. RT can palliate symptoms provided the disease is confined to a tolerable radiation field.

The effects of 41°C hyperthermia on the DNA repair protein, MRE11, correlate with radiosensitization in four human tumor cell lines

PURPOSE

The goal of this study was to determine if reduced availability of the DNA repair protein, MRE11, for the repair of damaged DNA is a basis for thermal radiosensitization induced by moderate hyperthermia. To test this hypothesis, we measured the total amount of MRE11 DNA repair protein and its heat-induced alterations in four human tumor cell lines requiring different heating times at 41 degrees C to induce measurable radiosensitization.

MATERIALS AND METHODS

Human colon adenocarcinoma cell lines (NSY42129, HT29 and HCT15) and HeLa cells were used as the test system. Cells were irradiated immediately after completion of hyperthermia. MRE11 levels in whole cell extract, nuclear extract and cytoplasmic extracts were measured by Western blotting. The nuclear and cytoplasmic extracts were separated by TX100 solubility. The subcellular localization of MRE11 was determined by immunofluorescence staining.

RESULTS

The results show that for the human tumor cell lines studied, the larger the endogenous amount of MRE11 protein per cell, the longer the heating time at 41 degrees C required for inducing measurable radiosensitization in that cell line. Further, the residual nuclear MRE11 protein level, measured in the nuclear extract and in the cytoplasmic extract as a function of heating time, both correlated with the thermal enhancement ratio (TER).

CONCLUSIONS

These observations are consistent with the possibility that delocalization of MRE11 from the nucleus is a critical step in the radiosensitization by moderate hyperthermia.

Protein microarray analysis of apoptosis-related protein expression following heat shock in human tongue squamous cell carcinomas containing different p53 phenotypes

PURPOSE

Hyperthermia is useful in the treatment of human head and neck cancers, because it is relatively easy to regulate temperatures when compared to tumors located in deep organs. In this study, attention was focused on p53 as a possible predictive indicator for the efficacy of hyperthermic cancer therapy.

METHODS

Two kinds of cell lines were used. These were derived from a human squamous cell carcinoma (SAS) and had identical genetic backgrounds except for their p53 gene status. It was previously reported that the heat sensitivity and frequency of apoptosis in wild-type p53 cells (SAS/neo) were clearly elevated when compared with mutated p53 cells (SAS/mp53). In order to study the expression of apoptosis related proteins after heat treatment, protein microarray analysis was used.

RESULTS

The expression of apoptosis inhibitory proteins such as Bcl-2, Bcl-xL, NF-kappaB, COX2, STAT3, IL-6, and IKKalpha/1 was seen to increase after heat treatment in SAS/mp53 cells, but not in SAS/neo cells.

CONCLUSION

The result of these observations indicates that apoptosis inhibitory proteins (such as Bcl-2, Bcl-xL, IL-6, etc.) were highly induced in SAS/mp53 cells after heat treatment when compared to control SAS/neo cells.