[Radiotherapy for Alleviation of Paraparesis due to Leptomeningeal and Cauda Equina Metastasis of HER2-Positive Breast Cancer: A Case Report].

Leptomeningeal metastasis is a rare entity and its diagnosis is often difficult. Moreover, evidence-based therapeutic strategies have not yet been established. A 52-year-old woman presented with high fever and was diagnosed with bacterial meningitis at first examination;although her fever was alleviated, she experienced motor weakness in both of her lower extremities. Ga scintigraphy highlighted the hot-spot areas of the disease in the cranial bone. She was then transferred to our department. Open biopsy of the skull showed metastasis of the cancer. Chest CT results indicated right breast cancer and Gd-DTPA imaging showed obvious enhancement of the pia mater around the conus medullaris and cauda equina. However, cerebrospinal fluid(CSF)cytological examination did not show the presence of any positive cells;consequently, mastectomy was performed in the thoracic surgical department. The severity of paraparesis and pain in her legs increased;however, repeat MRI 1 month later showed no evidence of any change. Therefore, we performed biopsy of the cauda equina and arachnoid lesions. The pathological diagnosis was metastasis of breast cancer with positive human epidermal growth factor receptor 2(HER2)immunological staining. The results of a repeat cytological examination of the CSF during the surgery were negative. Local radiotherapy(25 Gy/5 Fr)as a monotherapy was selected for the patient, because her family did not approve of the combination of radiotherapy and chemotherapy. The severity of both paraparesis and limb pain decreased immediately after the radiotherapy.

Involvement of UTR-dependent gene expression in the maintenance of cancer stem cell like phenotypes.

The present study demonstrated the acquisition of additional malignant characteristics in irradiated mouse fibrosarcoma cells compared with the parent cells. Several reporter assays indicated that hypoxia-inducible factor (HIF)-1α, activator protein-1 and Ets-dependent transcription were activated in irradiated cells. The cis-elements in the 5'-untranslated region (UTR) of these transcription factors plays a major role in their expression in surviving irradiated cancer cells. By contrast, there were no evident differences between the 3'-UTR-dependent repression demonstrated by parent cells and irradiated cells. A small population of parental fibrosarcoma cells was also found to exhibit the same enhanced 5'-UTR-dependent HIF-1α expression as that demonstrated by irradiated cells. These observations may indicate that high-dose X-ray irradiation affects the majority of proliferating cancer cells, but not the cancer stem cells (CSCs), and an increased CSC population may explain the progressive phenotypes of the irradiated cells. It appears likely that the transcription factors that maintain stemness are regulated by the same 5'-UTR-dependent mechanism.

Cell type-specific reciprocal regulation of HIF1A gene expression is dependent on 5'- and 3'-UTRs.

In the present study, we demonstrated the reciprocal regulation of hypoxia-inducible factor 1 alpha (HIF1A) gene expression via untranslated region-(UTR) dependent mechanisms. A 151 nucleotide sequence found in the HIF1A 5'-UTR is sufficient for significant translational up-regulation. On the other hand, the 3'-UTR of HIF1A has been implicated in mRNA degradation. In the non-metastatic breast cancer cell line MCF7, the 3'-UTR-dependent down-regulatory machinery predominates over the 5'-UTR-dependent up-regulation of HIF1A. However, 5'-UTR-dependent up-regulation is dominant among metastatic cell lines (MDA-MB453, U87MG). It is therefore likely that the predominance of 5'-UTR-dependent translational enhancement of HIF1A is critical for the malignant phenotype of cancer cells. PTBP-1, but not HuR, is a candidate RNA binding protein for the translational control of HIF1A.

Influence of respiration on dose calculation in stereotactic body radiotherapy of the lung.

Our purpose in this study was to evaluate the variation in calculated doses caused by respiration in stereotactic body radiotherapy (SBRT) of the lung. The study targeted ten patients who underwent SBRT for lung tumors. CT images were acquired during free breathing and in the inhalation and exhalation phases. We compared the CT image at inhalation with the image at exhalation so as to measure the change in lung volume, variation in the CT value, and displacement of the chest wall. The lung volume change was shown to be correlated with the maximum of the chest wall motion and with the variation in the CT value. A statistically significant difference was observed in the CT values between inhalation and exhalation (p < 0.05). The total dose variation at the isocenter was confined within ±2 %. However, the dose from individual beams can vary significantly when the chest wall moves more than 10 mm in natural breathing.

A formulation of cell surviving fraction after radiation exposure.

Local energy transfer from electrons generated in biotissues that are exposed to ionizing radiation is fundamental to cell damage. Our aim in this investigation was to quantify the probability of cell mortality associated with the damage by electrons and the repair processes in the cell nucleus, envisaging a new interpretation of the cell surviving fraction (SF). We introduced a SF formula for cells exposed to X-rays, which is given as a linear combination of the Poisson distributions about the number of long-lived lesions per nucleus and their "non-lethal probabilities", to show the non-linearity of log SF as a function of dose. The model selection was rated by a statistical index, Akaike's information criterion (AIC). It was shown that the new formula is suitable for describing cell survival and explicitly takes account of the non-lethality in damage-processing pathways of the cells.

Lung cancer cells that survive ionizing radiation show increased integrin α2ß1- and EGFR-dependent invasiveness.

Ionizing radiation (IR)-enhanced tumor invasiveness is emerging as a contributor to the limited benefit of radiotherapy; however, its mechanism is still unclear. We previously showed that subcloned lung adenocarcinoma A549 cells (P cells), which survived 10 Gy IR (IR cells), acquired high invasiveness in vitro. Here, we tried to identify the mechanism by which IR cells increase their invasiveness by examining altered gene expression and signaling pathways in IR cells compared with those in P cells. To simulate the microenvironment in vivo, cells were embedded in a three-dimensional (3D) collagen type I gel, in which the IR cells were elongated, while the P cells were spherical. The integrin expression pattern was surveyed, and expression levels of the integrin α2 and ß1 subunits were significantly elevated in IR cells. Knockdown of α2 expression or functional blockade of integrin α2ß1 resulted in a round morphology of IR cells, and abrogated their invasion in the collagen matrix, suggesting the molecule's essential role in cell spread and invasion in 3D collagen. Epidermal growth factor receptor (EGFR) also presented enhanced expression and activation in IR cells. Treatment with EGFR tyrosine kinase inhibitor, PD168393, decreased the ratio of elongated cells and cell invasiveness. Signaling molecules, including extracellular signal-regulated kinase-1/2 (Erk1/2) and Akt, exhibited higher activation in IR cells. Inhibition of Akt activation by treating with phosphoinositide 3-kinase (PI3K) inhibitor LY294002 decreased IR cell invasion, whereas inhibition of Erk1/2 activation by mitogen-activated protein kinase kinase (MEK) inhibitor U0126 did not. Our results show that integrin α2ß1 and EGFR cooperatively promote higher invasiveness of IR-survived lung cancer cells, mediated in part by the PI3K/Akt signaling pathway, and might serve as alternative targets in combination with radiotherapy.

Irradiation-tolerant lung cancer cells acquire invasive ability dependent on dephosphorylation of the myosin regulatory light chain.

Radiotherapy is one of the major treatment modalities for malignancies. However, cells surviving irradiation often display high levels of invasiveness. This study shows that irradiation-tolerant lung adenocarcinoma demonstrates high invasive capability depending on dephosphorylation of the myosin regulatory light chain (MRLC). In a collagen gel overlay condition, low-invasive subclones of lung adenocarcinoma (A549P-3) showed a round morphology and diphosphorylation of MRLC. In contrast, irradiation-tolerant A549P-3 cells (A549P-3IR) displayed high invasiveness and a lower level of MRLC diphosphorylation. In addition, inhibition of MRLC phosphatase activity decreased the invasive activity. These findings suggest that A549P-3IR cells acquire high invasiveness through MRLC dephosphorylation.

Investigation of the change in marker geometry during respiration motion: a preliminary study for dynamic-multi-leaf real-time tumor tracking.

BACKGROUND: The use of stereotactic body radiotherapy (SBRT) is rapidly increasing. Presently, the most accurate method uses fiducial markers implanted near the tumor. A shortcoming of this method is that the beams turn off during the majority of the respiratory cycle, resulting in a prolonged treatment time. Recent advances in collimation technology have enabled continuous irradiation to a moving tumor. However, the lung is a dynamic organ characterized by inhalation exhalation cycles, during which marker/tumor geometry may change (i.e., misalignment), resulting in under-dosing to the tumor. FINDINGS: Eight patients with lung cancer who were candidates for stereotactic radiotherapy were examined with 4D high-resolution CT. As a marker surrogate, virtual bronchoscopy using the pulmonary artery (VBPA) was conducted. To detect possible marker/tumor misalignment during the respiration cycle, the distance between the peripheral bronchus, where a marker could be implanted, and the center of gravity of a tumor were calculated for each respiratory phase. When the respiration cycle was divided into 10 phases, the median value was significantly larger for the 30%-70% respiratory phases compared to that for the 10% respiratory phase (P<0.05, Mann-Whitney U-test). CONCLUSIONS: These results demonstrate that physiological aspect must be considered when continuous tumor tracking is applied to a moving tumor. To minimize an "additional" internal target volume (ITV) margin, a marker should be placed approximately 2.5 cm from the tumor.

Lysyl oxidase: from basic science to future cancer treatment.

In this mini-review, we discuss the physiological and pathological roles of lysyl oxidase (LOX) and its family, LOX-like proteins (LOXL), in relation to prognosis of major cancers. The number of reports on LOX family is numerous. We have decided to review the articles that were recently published (i.e. past 5 years). Experimental techniques in molecular biology have advanced surprisingly in the past decade. Accordingly, the results of the studies are more reliable. Most studies reached the same conclusion; a higher LOX- or LOXL- expression is associated with a poor prognosis. Molecular experiments have already started aiming for clinical application, and the results are encouraging. Suppressing LOX or LOXL activities resulted in lower cell motility in collagen gel and, moreover, succeeded in reducing metastases in mice. LOX family members were originally recognized as molecules that cross-link collagen fibers in the extracellular matrix. Recent studies demonstrated that they are also involved in a phenomenon called Epithelial Mesenchymal Transition (EMT). This may affect cell movement and cancer cell invasiveness. LOX and LOXL2 are regulated by hypoxia, a major factor in the failure of cancer treatment. Here we discuss the molecular biology of the LOX family in relation to its role in tumor biology.

Radiation-induced cancer cell repopulation: a possible mechanism implied by experiments using transplantable mouse-derived sarcoma cell line.

PURPOSE: Treatment with any cytotoxic agent can trigger surviving cells in a tumor to divide faster than before. This phenomenon is widely recognized as "repopulation". To better clarify the mechanism, gene expression profiling and pathological experiments were performed. MATERIALS AND METHODS: A mouse fibrosarcoma cell line, QRsP, was used. Cells were irradiated with 10 Gy. Colony assay and cloning were performed. Six clones were established. cDNA analysis was performed on the clone that showed the largest number of colonies on the 2nd 10 Gy irradiation. Mouse transplantation experiment was then carried out. RESULTS: cDNA analysis showed that cyclin-dependent kinase inhibitors, p16 and p57 were down-regulated; 14.8- and 12.0-fold, respectively for the tolerant clone. Matrix metalloproteinase 3 and 13 were up-regulated; 22.5- and 25.8-fold, respectively. Transplantation ratio was 100% (5/5) for the tolerant clone whereas it was 40% (2/5) for the parent. Under light microscope, the mean mitotic cell number was 4.0+/-3.9 for the parent, and 12.8+/-3.4 for the tolerant clone (p<0.01, Student's t-test). CONCLUSIONS: This study implies that repopulation is not a temporary reaction to irradiation. It is caused probably by "clonal" gene-expression changes, though it remains unknown whether the changes are attributable to tolerant cell selection or to gene mutation/modification.

Clinical characteristics and computed tomography findings in children with 2009 pandemic influenza A (H1N1) viral pneumonia.

In this article we review the clinical characteristics and computed tomography (CT) findings in children with 2009 pandemic H1N1 influenza viral pneumonia. The medical charts of 88 children with pandemic H1N1 influenza virus infection, admitted to our hospital in Japan from 10 August to 28 December 2009, were reviewed; we compared the clinical features of these children with those of 61 children admitted with seasonal influenza A during the previous 3 seasons. Of 88 patients, 53 (60%) had radiographic findings consistent with pneumonia and 34 patients underwent a chest computed tomography (CT) scan. Pneumonia was a more frequent complication in children with pandemic H1N1 influenza compared with those with seasonal influenza (60% vs 11%; p < 0.001). The predominant CT findings were unilateral or bilateral multifocal consolidation (15/34; 44%) associated with ground-glass opacities in the peribronchovascular region. The second most common CT finding was unilateral diffuse consolidation or atelectasis in 1 or more lung zones (12/34; 35%). The chest CT findings of unilateral or bilateral multifocal consolidation often associated with ground-glass opacities were commonly seen in children with pandemic H1N1 influenza viral pneumonia. Atelectasis was seen in patients who required oxygen administration.

Cesium implant for tongue carcinoma with a thickness of 1.5 cm or more: cases successfully treated with a Modified Manchester System.

PURPOSE: Deciding on treatment carcinoma of the tongue when the tumor has a thickness of 1.5 cm or more is difficult. Surgery often requires wide resection and re-construction, leading to considerable functional impairment. A cesium implant is an attractive option, but according to the Manchester System, a two plane implant is needed. MATERIALS AND METHODS: According to the textbook, a tumor is sandwiched between the needles, which are implanted at the edge of the tumor. This may cause an unnecessarily high dose to the outer surface of the tongue, which sometimes leads to a persistent ulcer. To avoid this complication, we invented a modified implantation method, and applied the method to five consecutive patients. RESULTS: With a minimum follow-up of 2 years, all primary tumors in 5 consecutive patients have been controlled. No complications occurred in soft tissue of the tongue or in the mandible. CONCLUSION: Our modified Manchester System was feasible and effective for tumors that has a thickness of 1.5 cm or more.

Integrin beta1-dependent invasive migration of irradiation-tolerant human lung adenocarcinoma cells in 3D collagen matrix.

Radiotherapy is one of the effective therapies used for treating various malignant tumors. However, the emergence of tolerant cells after irradiation remains problematic due to their high metastatic ability, sometimes indicative of poor prognosis. In this study, we showed that subcloned human lung adenocarcinoma cells (A549P-3) that are irradiation-tolerant indicate high invasive activity in vitro, and exhibit an integrin beta1 activity-dependent migratory pattern. In collagen gel overlay assay, majority of the A549P-3 cells displayed round morphology and low migration activity, whereas a considerable number of A549P-3IR cells surviving irradiation displayed a spindle morphology and high migration rate. Blocking integrin beta1 activity reduced the migration rate of A549P-3IR cells and altered the cell morphology allowing them to assume a round shape. These results suggest that the A549P-3 cells surviving irradiation acquire a highly invasive integrin beta1-dependent phenotype, and integrin beta1 might be a potentially effective therapeutic target in combination with radiotherapy.

Increased motility and invasiveness in tumor cells that survive 10 Gy irradiation.

Radiotherapy is an important noninvasive treatment for many types of cancer. However, it has been reported that the proliferative, invasive, and metastatic capacities of tumor cells can be increased in the repopulated tumors that survive radiotherapy. We have previously established a radiation-surviving cell model for the human non-small cell lung cancer cell line H1299 by harvesting relic cells 14 days after irradiation (IR cells). Here, we report that cell invasion, cell migration, and cell adhesion are enhanced in these surviving cancer cells. The mRNA expression levels of matrix metalloproteinases (MMPs), including mmp1, mmp2, and mmp9, were upregulated in IR cells compared with parental cells. A gelatin zymogram, wound healing assay, and invasion assay showed increased MMP activity, cell motility, and invasiveness in IR cells, respectively. Moreover, IR cells adhered more tightly to collagen-coated dishes than parental cells. Consistently, paxillin, phosphorylated FAK, integrin beta1, and vinculin were strongly localized at focal adhesions in IR cells, as visualized by immunofluorescence. In this report, we identify molecules responsible for the malignant properties of tumor cells that survive irradiation. These molecules may be important therapeutic targets for the control of repopulated tumors after radiotherapy.

Synchronous monitoring of external/internal respiratory motion: validity of respiration-gated radiotherapy for liver tumors.

PURPOSE: Four-dimensional (4D) radiotherapy, in particular respiration gating for the treatment of lung tumors, is gaining popularity. Its utility for other sites, however, has not been investigated fully. The purpose of this study was to see whether 4D therapy is feasible for liver tumors. MATERIAL AND METHODS: Six patients (five with hepatomas and one with metastatic liver tumor) had a fiducial, gold marker 1.5 mm in diameter implanted in the vicinity of their liver tumors. The inner and external (i.e., upper abdominal wall) respiratory movements were simultaneously recorded using a real-time tumor-tracking radiotherapy system and respiration monitor equipment applied to the mid to upper abdomen. RESULTS: The fluctuations from the baseline position of liver tumors were small; the mean absolute value was 3.92 +/- 1.94 mm. The mean right-left, anteroposterior, and craniocaudal total movements were 4.19 +/- 2.46, 7.23 +/- 2.96, and 15.98 +/- 6.02 mm, respectively. The phase shift was negligible. CONCLUSION: Liver tumors may be suitable for respiration-gated radiotherapy, and they may become curable with 4D radiotherapy.

Superselective high-dose cisplatin infusion with concomitant radiotherapy in patients with advanced cancer of the nasal cavity and paranasal sinuses: a single institution experience.

BACKGROUND: The current study aimed to evaluate the efficacy of superselective high-dose cisplatin infusion with concomitant radiotherapy (RADPLAT) for previously untreated patients with advanced cancer of the nasal cavity and paranasal sinuses. METHODS: Between October 1999 and December 2006, 47 patients were given superselective intra-arterial infusions of cisplatin (100-120 mg/m2 per week) with simultaneous intravenous infusions of thiosulfate to neutralize cisplatin toxicity and conventional external-beam radiotherapy (65-70 grays). RESULTS: There were 7 patients (14.9%) diagnosed with T3, 22 (46.8%) with T4a, and 18 (38.3%) with T4b disease. During the median follow-up period of 4.6 years, the 5-year local progression-free survival rate was 78.4% for all patients (n=47), 69.0% for patients with T4b disease (n=18), and 83.2% for patients with

Value of fluorodeoxyglucose positron emission tomography before radiotherapy for head and neck cancer: does the standardized uptake value predict treatment outcome?

PURPOSE: The aim of this study was to determine if the standardized uptake value (SUV) of fluorodeoxyglucose positron emission tomography (FDG-PET) for head and neck cancer can predict the outcome of radiotherapy and if the SUV is correlated with histological grade, mitosis, and apoptosis. MATERIALS AND METHODS: The study included 45 head and neck cancer patients who underwent FDG-PET scanning before radiotherapy. The maximum SUV (SUVmax) of their primary lesions were measured. Biopsy was performed in all patients to determine the histological diagnosis. Altogether, 14 biopsy specimens were available for mitotic and apoptotic cell counts. RESULTS: The mean SUVmax of T3 tumors was significantly higher than that of T1 (P = 0.01) and T2 (P = 0.011) tumors. The mean SUVmax of stage II disease was significantly lower than that of stage III (P = 0.028) and stage IV (P = 0.007) disease. There was a tendency toward a better locoregional control rate and disease-free survival for the lower SUV group using a cutoff value of 5.5. For 41 patients with squamous cell carcinoma or undifferentiated carcinoma, SUVmax did not reflect the histological grade. There was no correlation between the SUVmax and the mitotic/apoptotic status. CONCLUSION: SUVmax may correlate with the T classification and stage, but there was no predictive value for outcome of radiation therapy. Neither histological grading nor mitotic/apoptotic status is correlated with SUVmax.

Novel function of transcription factor ATF5: blockade of p53-dependent apoptosis induced by ionizing irradiation.

PURPOSE: To find a new molecule that affects p53-dependent radiosensitivity. METHODS AND MATERIALS: A mouse sarcoma cell line, QRsP(p53+/+), was used. From this cell line, we established a radiosensitive clone and a radioresistant one. Colony assay, p53 gene transfer, a luciferase assay for p53 and p21, animal transplantation experiment, and DNA array analyses were performed. RESULTS: Microarray showed marked reduction of a transcription factor, ATF5, both in vitro and in vivo for the radiosensitive clone. Interestingly, flow cytometric analysis demonstrated marked apoptosis for the radiosensitive clone by p53 cloned adenovirus infection. Luciferase reporter assay revealed that ATF5 suppressed the transactivational activity of p53 and p63. By ATF5 gene transfer, the radiosensitive clone regained resistance to both ionizing-radiation and Ad-p53 infection-induced cell death. Surprisingly, time-lapse cell migration observation revealed greater cell motility for ATF5-transfected radiosensitive clone. CONCLUSIONS: It seems likely that ATF5 is a potent repressor of p53 and elevated expression of ATF5 in a tumor may relate to enhanced malignant phenotypes, such as radioresistance or greater cell motility.

Surgical complications of salvage total laryngectomy following concurrent chemoradiotherapy.

BACKGROUND: Surgical complication rates of total laryngectomy vary according to the preoperative treatments performed and patient factors. Wound complications after salvage laryngectomy following concurrent chemoradiotherapy (CCRT) were analyzed. METHODS: Eighty-six patients who had undergone total laryngectomy for laryngeal cancer at Hokkaido University Hospital, Japan, between 1990 and 2006 were divided into three groups according to preoperative treatments received: group I (n = 35) without radiotherapy (RT) or CCRT, group II (n = 17) RT alone, and group III (n = 34) low-dose CCRT. Salvage total laryngectomy was performed as a consequence of residual or recurrent disease after completion of the treatments. Wound complications such as pharyngocutaneous fistulas, bleeding, infections, and skin necrosis were retrospectively analyzed in each group. RESULTS: A considerable (not statistically significant) difference in the incidence of major wound complications was observed between groups I and III (11.4% vs 29.4%, P = 0.078), but not between groups II and III. In stage III/IV patients, a significant increase in the incidence of wound complications was observed in group III compared to group I. Pharyngocutaneous fistulas were the most common complication, occurring in 8/34 (23.5%) of the group III patients. Additional pharyngeal reconstruction surgery was performed in 5 of the 8 (62.5%) group III patients with pha ryngocutaneous fistulas, while no such patients (0/3) in group I required reconstruction surgery. CONCLUSION: There was an increased risk of wound complications in patients undergoing salvage laryngectomy following CCRT. Patients who developed pharyngocutaneous fistulas after CCRT tended to require surgical reintervention for repair. These findings should be taken into account before the initiation of CCRT and salvage surgery.