Effects of adoptive T-cell immunotherapy on immune cell profiles and prognosis of patients with unresectable or recurrent cholangiocarcinoma.

The identification of immune cell profiles (ICP) involved in anti-tumor immunity is crucial for immunotherapy. Therefore, we herein investigated cholangiocarcinoma patients (CCA) who received adoptive T-cell immunotherapy (ATI). Eighteen unresectable or recurrent CCA received ATI of αß T cells alone or combined with chemotherapy. ICP were evaluated by flow cytometry. There were 14 patients with intrahepatic cholangiocarcinoma (iCCA) and four with distal cholangiocarcinoma (dCCA). After one course of treatment, nine iCCA and four dCCA had progressive disease (PD), while five iCCA had stable disease (SD). Median overall survival (OS) was prolonged to 21.9 months. No significant differences were observed in OS between the PD and SD groups of iCCA. The frequency of helper T cells (HT) in iCCA decreased from 70.3% to 65.5% (P = .008), while that of killer T cells (KT) increased from 27.0% to 30.6% (P = .005). dCCA showed no significant changes of immune cells. OS was prolonged in iCCA with increased frequencies of CD3+ T cells (CD3) (P = .039) and αß T cells (αß) (P = .039). dCCA showed no immune cells associated with OS. The frequencies of CD3+ T cells and αß T cells in the PD group for iCCA decreased from 63.5% to 53% (P = .038) and from 61.6% to 52.2% (P = .028), respectively. In the SD group, the frequency of HT decreased from 65.8% to 56.9% (P = .043), whereas that of KT increased from 30.1% to 38.3% (P = .043). In conclusions, ATI affected ICP and prolonged OS. Immune cells involved in treatment effects differed according to the site of cholangiocarcinoma.

Safety evaluation of immune-cell therapy for malignant tumor in the Cancer Immune-cell Therapy Evaluation Group (CITEG).

BACKGROUND AIMS: With the aim of strengthening the scientific evidence of immune-cell therapy for cancer and further examining its safety, in October 2015, our hospital jointly established the Cancer Immune-Cell Therapy Evaluation Group (CITEG) with 39 medical facilities nationwide. METHODS: Medical information, such as patients' background characteristics, clinical efficacy and therapeutic cell types obtained from each facility, has been accumulated, analyzed and evaluated by CITEG. In this prospective study, we analyzed the adverse events associated with immune-cell therapy until the end of September 2022, and we presented our interim safety evaluation. RESULTS: A total of 3839 patients with malignant tumor were treated with immune-cell therapy, with a median age of 64 years (range, 13-97 years) and a male-to-female ratio of 1:1.08 (1846:1993). Most patients' performance status was 0 or 1 (86.8%) at the first visit, and 3234 cases (84.2%) were advanced or recurrent cases, which accounted for the majority. The total number of administrations reported in CITEG was 31890, of which 960 (3.0%) showed adverse events. The numbers of adverse events caused by treatment were 363 (1.8%) of 19661 administrations of αßT cell therapy, 9 of 845 administrations of γδT-cell therapy (1.1%) and 10 of 626 administrations of natural killer cell therapy (1.6%). The number of adverse events caused by dendritic cell (DC) vaccine therapy was 578 of 10748 administrations (5.4%), which was significantly larger than those for other treatments. Multivariate analysis revealed that αßT cell therapy had a significantly greater risk of adverse events at performance status 1 or higher, and patients younger than 64 years, women or adjuvant immune-cell therapy had a greater risk of adverse events in DC vaccine therapy. Injection-site reactions were the most frequently reported adverse events, with 449 events, the majority of which were associated with DC vaccine therapy. Among all other adverse events, fever (228 events), fatigue (141 events) and itching (131 events) were frequently reported. In contrast, three patients had adverse events (fever, abdominal pain and interstitial pneumonia) that required hospitalization, although they were weakly related to this therapy; rather, it was considered to be the effect of treatment for the primary disease. CONCLUSIONS: Immune-cell therapy for cancer was considered to be a safe treatment without serious adverse events.

Surgical Metastasectomy in the Spine: A Review Article.

BACKGROUND: The use of surgical metastasectomy (SM) has increased across cancer types in recent decades despite the increasing efficacy of modern systemic treatment modalities. Symptomatic spinal metastases severely compromise patients' performance status. However, as spinal SM is a complex surgery with potentially significant complications, it is not considered the treatment of choice. METHODS: We reviewed the articles on SM in several primary cancers with different types of metastatic lesions and extracted the data from relevant articles to provide a comprehensive review including the surgical techniques, indications, reported outcomes, and future prospects of SM in spinal metastases. RESULTS: Total en bloc spondylectomy (TES) is a method of spinal SM associated with a lower risk of tumor recurrence and complications. Intralesional transpedicular osteotomy using a fine threadwire saw allows prevention of spinal cord and nerve root injuries. Spinal SM is considered suitable for patients with controlled primary disease having no evidence of disseminated extraspinal metastases, a completely resectable solitary lesion in the spine, and adequate cardiopulmonary reserve to tolerate the surgery. Metastatic lesions from kidney and thyroid cancers have been reported as the best candidates for spinal SM. Although data about spinal SM are limited, the reported outcomes are favorable with acceptable local recurrence rates in long-term follow-up. CONCLUSION: In patients with isolated resectable spinal metastases, complete SM including TES is a useful option as it can improve function and survival. However, appropriate patient selection and surgical feasibility remain the most important aspects of management. IMPLICATIONS FOR PRACTICE: Surgical metastasectomy for spinal metastases may be a potentially curative treatment option with a low risk of local recurrence and lead to prolonged long-term survival if appropriate patients are selected and if the surgery is carried out by experienced surgeons in high-volume centers.

Effect of adoptive T-cell immunotherapy on immunological parameters and prognosis in patients with advanced pancreatic cancer.

BACKGROUND AIMS: Immunotherapy is effective for many types of cancer, but its benefits in advanced pancreatic cancer, which has a poor prognosis, are not well established. In this study, the authors examined the effects of adoptive T-cell immunotherapy (ATI) on immune cell profiles and prognosis in patients with unresectable advanced pancreatic cancer. METHODS: Seventy-seven patients with unresectable advanced pancreatic cancer were treated with six cycles of αß T cells alone or in combination with chemotherapy or chemoradiation. Immune cell profiles in peripheral blood samples obtained before and after treatment were comprehensively evaluated by flow cytometry. Furthermore, associations between changes in immune cell frequencies and prognosis were determined. RESULTS: ATI prolonged survival to 18.7 months compared with previous estimates of 6.2-11.1 months for patients treated with chemotherapy alone. ATI decreased CD3+CD4+CD8- T cell frequency in peripheral blood and increased CD3+CD4-CD8+ T cell frequency. An increase in CD3+ T cells and CD3+TCRγδ- T cells in peripheral blood after treatment was associated with a good prognosis. CONCLUSIONS: ATI altered the immune profile in peripheral blood, including CD3+CD4-CD8+ T cells, and improved prognosis in pancreatic cancer.

Identification of prognostic factors for γδT cell immunotherapy in patients with solid tumor.

BACKGROUND AIMS: Activated γδT cells have been shown to exhibit cytotoxicity against tumor cells. However, the efficacy of γδT cell immunotherapy for a large number of patients with solid tumors remains unclear. In this study, we examined the efficacy of γδT cell immunotherapy using in vitro-activated γδT lymphocytes in combination with standard therapies in terms of the survival of patients with solid tumors, and determined prognostic factor for γδT cell immunotherapy. METHODS: 131 patients enrolled in this study received γδT cell immunotherapy with or without standard therapies. Their overall survival was analyzed by the Kaplan-Meier with log-rank test and Cox regression methods. Immunological analysis was performed by flow cytometry (FCM) before and after six cycles of γδT cell immunotherapy. RESULTS: Multivariable analysis revealed that patients who showed stable disease (SD) and partial response (PR) to γδT cell immunotherapy showed better prognosis than those with a progressive disease (PD) (P = 0.0269, hazard ratio [HR], 0.410, 95% confidence interval [CI], 0.190-0.901). Furthermore, when immunological parameters were examined by FCM, the high Vγ9/γδT ratio (i.e., the high purity of the Vγ9 cells within the adoptively transferred γδT cells) before treatment was found to be a good prognostic factor for γδT cell immunotherapy (P = 0.0142, HR, 0.328, 95% CI, 0.125-0.801). No serious adverse events were reported during γδT cell immunotherapy. CONCLUSION: Thus, γδT cell immunotherapy might extend the survival of patients with solid tumors.

Clinical outcomes and survivals after total en bloc spondylectomy for metastatic leiomyosarcoma in the spine.

PURPOSE: Leiomyosarcoma (LMS) is generally resistant to radiation and chemotherapy. Our study aimed to examine the outcomes of total en bloc spondylectomy (TES) for spinal metastatic LMS and to analyze potential factors associated with survival. METHODS: This study included 10 consecutive patients who underwent TES for spinal metastatic LMS at our institute between 2005 and 2016 and were followed up at a minimum of 3 years after surgery. At the time of TES, all the 10 patients had solitary bone metastases in the spine. Seven patients had a lowered performance status (PS) with an eastern cooperative oncology group (ECOG) grade of 2 or 3 due to back pain or neurological symptoms. The cancer-specific survival (CSS) time from TES to death or last follow-up was the main endpoint. Potential factors associated with survival were evaluated using the Kaplan-Meier analysis and the log-rank test. RESULTS: Five patients underwent a single vertebral resection, and the other five patients underwent two or three consecutive vertebral resections. Three patients developed perioperative complications including pulmonary thromboembolism and pneumothorax. Nine patients improved or fairly maintained their PS with an ECOG grade of 1. The 1-, 3-, and 5-year CSS rates after TES were 90%, 70%, and 47%, respectively. Only postoperative disability (ECOG PS grade 3) was significantly associated with short-term survival after TES. CONCLUSIONS: The clinical outcomes of 10 patients who underwent TES for spinal metastatic LMS were favorable without severe complications. Postoperative disability was significantly associated with short-term survival after TES.

How good are the outcomes of instrumented debulking operations for symptomatic spinal metastases and how long do they stand? A subgroup analysis in the global spine tumor study group database.

BACKGROUND: The benefits of surgery for symptomatic spinal metastases have been demonstrated, largely based on series of patients undergoing debulking and instrumentation operations. However, as cancer treatments improve and overall survival lengths increase, the incidence of recurrent spinal cord compression after debulking may increase. The aim of the current paper is to document the postoperative evolution of neurological function, pain, and quality of life following debulking and instrumentation in the Global Spine Tumor Study Group (GSTSG) database. METHODS: The GSTSG database is a prospective multicenter data repository of consecutive patients that underwent surgery for a symptomatic spinal metastasis. For the present analysis, patients were selected from the database that underwent decompressive debulking surgery with instrumentation. Preoperative tumor type, Tomita and Tokuhashi scores, EQ-5D, Frankel, Karnofsky, and postoperative complications, survival, EQ-5D, Frankel, Karnofsky, and pain numeric rating scores (NRS) at 3, 6, 12, and 24 months were analyzed. RESULTS: A total of 914 patients underwent decompressive debulking surgery with instrumentation and had documented follow-up until death or until 2 years post surgery. Median preoperative Karnofsky performance index was 70. A total of 656 patients (71.8%) had visceral metastases and 490 (53.6%) had extraspinal bone metastases. Tomita scores were evenly distributed above (49.1%) and below or equal to 5 (50.9%), and Tokuhashi scores almost evenly distributed below or equal to 8 (46.3%) and above 8 (53.7%). Overall, 12-month survival after surgery was 56.3%. The surgery resulted in EQ-5D health status improvement and NRS pain reduction that was maintained throughout follow-up. Frankel scores improved at first follow-up in 25.0% of patients, but by 12 months neurological deterioration was observed in 18.8%. CONCLUSION: We found that palliative debulking and instrumentation surgeries were performed throughout all Tomita and Tokuhashi categories. These surgeries reduced pain scores and improved quality of life up to 2 years after surgery. After initial improvement, a proportion of patients experienced neurological deterioration by 1 year, but the majority of patients remained stable.

Spinal metastasectomy of renal cell carcinoma: A 16-year single center experience with a minimum 3-year follow-up.

BACKGROUND AND OBJECTIVES: Metastasectomy of spinal lesions from renal cell carcinoma (RCC) is a promising strategy. However, its clinical outcome after spinal metastasectomy is unknown owing to the difficulty of curative surgical resection. This is the first study to examine the survival rates of patients who underwent metastasectomy of solitary spinal metastases from RCC. METHODS: A retrospective cohort study of 36 consecutive patients with RCC who underwent nephrectomy and complete removal of solitary spinal lesions between 1995 and 2010 at our institution. Cancer-specific survival (CSS) time from the spinal metastasectomy to death or last follow-up was the main endpoint. Potential factors associated with survival were evaluated with Kaplan-Meier analysis and the long-rank test. RESULTS: For all patients, the estimated median CSS time was 130 months. The 3, 5, and 10-year CSS rates were 77.8%, 69.1%, and 58.0%, respectively, for all patients, and 72.7%, 54.5%, and 27.3%, respectively, for patients with lung metastases at the time of surgery. Only the presence of liver metastases was significantly associated with short-term survival after spinal metastasectomy. CONCLUSIONS: Liver metastases were associated with short-term survival, although lung metastases were not. For selected patients, curative resection of solitary spinal metastases can potentially prolong survival. J. Surg. Oncol. 2016;113:587-592. © 2016 Wiley Periodicals, Inc.

Rapid improvements in pain and quality of life are sustained after surgery for spinal metastases in a large prospective cohort.

Introduction Metastatic spinal cancer is a common condition that may lead to spinal instability, pain and paralysis. In the 1980s, surgery was discouraged because results showed worse neurological outcomes and pain compared with radiotherapy alone. However, with the advent of modern imaging and spinal stabilisation techniques, the role of surgery has regained centre stage, though few studies have assessed quality of life and functional outcomes after surgery. Objective We investigated whether surgery provides sustained improvement in quality of life and pain relief for patients with symptomatic spinal metastases by analysing the largest reported surgical series of patients with epidural spinal metastases. Methods A prospective cohort study of 922 consecutive patients with spinal metastases who underwent surgery, from the Global Spine Tumour Study Group database. Pre- and post-operative EQ-5D quality of life, visual analogue pain score, Karnofsky physical functioning score, complication rates and survival were recorded. Results Quality of life (EQ-5D), VAS pain score and Karnofsky physical functioning score improved rapidly after surgery and these improvements were sustained in those patients who survived up to 2 years after surgery. In specialised spine centres, the technical intra-operative complication rate of surgery was low, however almost a quarter of patients experienced post-operative systemic adverse events. Conclusion Surgical treatment for spinal metastases produces rapid pain relief, maintains ambulation and improves good quality of life. However, as a group, patients with cancer are vulnerable to post-operative systemic complications, hence the importance of appropriate patient selection.

More than 10-year follow-up after total en bloc spondylectomy for spinal tumors.

BACKGROUND: There are many reports of en bloc resection for spinal tumors. However, no studies have evaluated the clinical outcomes with follow-up exceeding 10 years after surgery. METHODS: We reviewed 82 patients who had undergone total en bloc spondylectomy (TES) before January 2002 and identified 29 (19 with primary tumors and 10 with metastatic tumors) who had survived for more than 10 years after surgery. We evaluated the clinical outcomes including patient-based outcomes using questionnaire. The questionnaire included subjective assessment of the results of TES and SF-36. RESULTS: Overall, 33 % of patients with metastases from kidney cancer and 25 % of those with metastases from thyroid cancer survived for more than 10 years after TES for solitary spinal metastases. Four patients with metastatic tumors had no evidence of disease at the time of survey. There were no tumor recurrences in any of the 23 patients who underwent TES as the primary surgery. No revision surgeries have been required as a result of instrumentation failure in any of the 29 patients. About 90 % of the patients were satisfied or very satisfied with the results of TES. The SF-36 results demonstrated that the both physical and mental health of patients with primary tumors was equivalent to those of healthy individuals, and the mental health of patients with metastatic tumors was almost similar to them. CONCLUSIONS: This study showed the long-term clinical outcomes after TES to be favorable. TES played an important role in the treatment strategy for spinal tumors including metastases.

The effect of spinal shortening after total en bloc spondylectomy: a biomechanical study in the thoracic spine.

STUDY DESIGN: A biomechanical study using human cadaveric thoracic spine specimens. OBJECTIVE: To evaluate and compare the biomechanical effects of spinal shortening and cross-links in reconstruction after total en bloc spondylectomy (TES). SUMMARY OF BACKGROUND DATA: There have been no studies that have examined the biomechanical effects of spinal reconstruction after multilevel TES or the biomechanical effects of spinal shortening in reconstruction after TES. METHODS: Eight human cadaveric spines (T2-T9) were used. After the intact specimen had been biomechanically tested to determine the stiffness in compression, flexion, extension, left and right lateral bending, and left and right axial rotation, a TES at T5-6 was carried out. Three reconstruction methods were tested biomechanically (same as for the intact specimen) for their ability to restore stiffness to the specimen: (1) anterior short cage and multilevel posterior instrumentation at T3-8 with 2 cross-links (S2C), (2) anterior short cage and multilevel posterior instrumentation at T3-8 with 1 cross-link (S1C), and (3) anterior long cage and multilevel posterior instrumentation at T3-8 with 2 cross-links (L2C). A cage that was 6-10 mm shorter in height than the space created by the TES at T5-6 was selected as the "short cage" and a cage 10 mm taller in height than the short cage was selected as the "long cage" in each specimen. RESULTS: All 3 reconstruction methods using an anterior cage and multilevel posterior instrumentation provides a stiffer construct than that shown by the intact specimen. The reconstruction method using the 10-mm shorter cage (S2C vs. L2C) provided more stiffness than the one using the longer cage. The reconstruction using 2 cross-links (S2C vs. S1C) did not provide a stiffer construct than the one using 1 cross-link. CONCLUSIONS: The reconstructions using an anterior cage and multilevel posterior instrumentation provided a stiffer construct than that shown by the intact specimen. The reconstruction using a 10-mm shorter cage provided a stiffer construct than the reconstruction using the longer cage.

A synthetic compound that potentiates bone morphogenetic protein-2-induced transdifferentiation of myoblasts into the osteoblastic phenotype.

There is an urgent need to develop methods that lower costs of using recombinant human bone morphogenetic proteins (BMPs) to promote bone induction. In this study, we demonstrate the osteogenic effect of a low-molecular weight compound, SVAK-12, that potentiated the effects of BMP-2 in inducing transdifferentiation of C2C12 myoblasts into the osteoblastic phenotype. Here, we report a specific compound, SVAK-12, which was selected based on in silico screenings of small-molecule databases using the homology modeled interaction motif of Smurf1-WW2 domain. The enhancement of BMP-2 activity by SVAK-12 was characterized by evaluating a BMP-specific reporter activity and by monitoring the BMP-2-induced expression of mRNA for osteocalcin and alkaline phosphatase (ALP), which are widely accepted marker genes of osteoblast differentiation. Finally, we confirmed these results by also measuring the enhancement of BMP-2-induced activity of ALP. Smurf1 is an E3 ligase that targets osteogenic Smads for ubiquitin-mediated proteasomal degradation. Smurf1 is an interesting potential target to enhance bone formation based on the positive effects on bone of proteins that block Smurf1-binding to Smad targets or in Smurf1-/- knockout mice. Since Smads bind Smurf1 via its WW2 domain, we performed in silico screening to identify compounds that might interact with the Smurf1-WW2 domain. We recently reported the activity of a compound, SVAK-3. However, SVAK-3, while exhibiting BMP-potentiating activity, was not stable and thus warranted a new search for a more stable and efficacious compound among a selected group of candidates. In addition to being more stable, SVAK-12 exhibited a dose-dependent activity in inducing osteoblastic differentiation of myoblastic C2C12 cells even when multiple markers of the osteoblastic phenotype were parallelly monitored.

Potentiation of the antitumor effect of calcium phosphate cement containing anticancer drug and caffeine on rat osteosarcoma.

BACKGROUND: Several reports suggest diffusion of anticancer agents from bone cement may suppress tumor growth. New drug delivery systems have been developed that incorporate anticancer drugs into calcium phosphate cement (CPC) to maintain high concentrations of anticancer drugs at local sites. We investigated whether CPC implants containing anticancer drugs and caffeine, which enhance the cytocidal effect of anticancer drugs, would enhance their antitumor effects on rat osteosarcomas (SOSN2 cells). METHODS: We calculated the release of cisplatin (CDDP) and caffeine from the CPC and bone cement. The following CPCs were prepared: CPC-only, CPC containing caffeine, CPC containing cisplatin, and CPC containing cisplatin and caffeine. We performed cell growth inhibition assays on SOSN2 cells using culture media previously used to incubate each CPC. We transplanted SOSN2 cells into the tibias of rats, excised the tumor 3 days after transplantation, implanted each CPC and observed subsequent tumor growth. RESULTS: The in vitro sustained-release test demonstrated greater amounts and more persistent release of CDDP and caffeine from CPC than from bone cement and also showed CPC could release the majority of its loaded CDDP and caffeine. Culture media containing CDDP and caffeine inhibited in vitro proliferation of SOSN2 cells, and this inhibitory effect was greater than the inhibition resulting from CDDP alone. Experiments with an in vivo rat model demonstrated greater tumor growth inhibition with CPC containing CDDP and caffeine than with CPC containing CDDP alone. CONCLUSIONS: The study results suggest CPC containing CDDP and caffeine potentiate antitumor effects and may be effective as a local chemotherapeutic method of treating malignant bone tumors.

The route of metastatic vertebral tumors extending to the adjacent vertebral body: a histological study.

BACKGROUND: Each vertebra can be regarded as a compartment surrounded by several anatomically characterized barriers. However, in some cases tumors extend beyond these barriers. The route of vertical extension to the adjacent vertebrae is unclear. The extent of vertical extension of a metastatic spinal tumor is important in making the preoperative decision regarding the cranio-caudal surgical margin. The objective of this study was to investigate the route of vertical extension of metastatic vertebral tumors. METHODS: We examined 20 en bloc resected metastatic vertebral bodies in which the tumors had extended outside the vertebral body. Five to eight sagittal sections including the pedicle, and the lateral and central parts of the PLL were prepared from each resected specimen. The sections were stained with hematoxylin and eosin, and elastica van Gieson. Histological examination focused on the routes of the vertical extension of the tumor at each barrier tissue and the degree of tumor extension along each route. RESULTS: Vertical extension of the tumor was observed at the ALL in 6 cases, at the central part of the PLL in 14 cases, at the lateral part of the PLL in 20 cases, at the cartilaginous endplate in 3 cases, and at the periosteum on the lateral side of vertebral body in 7 cases. The tumor had extended the farthest at the lateral part of the PLL in 18 cases, at the lateral side of the vertebral body in 1 case, and through the disc in 1 case. CONCLUSIONS: Metastatic vertebral tumors most commonly extend vertically at the lateral part of the PLL. The lateral part of the PLL is raised by the tumor, which extends between the PLL and the posterior aspect of the disc.

Perioperative complications of total en bloc spondylectomy for spinal tumours.

AIMS: To evaluate the perioperative complications associated with total en bloc spondylectomy (TES) in patients with spinal tumours, based on the extent and level of tumour resection. METHODS: In total, 307 patients who underwent TES in a single centre were reviewed retrospectively. There were 164 male and 143 female patients with a mean age at the time of surgery of 52.9 years (SD 13.3). A total of 225 patients were operated on for spinal metastases, 34 for a malignant primary tumour, 41 for an aggressive benign tumour, and seven with a primary of unknown origin. The main lesion was located in the thoracic spine in 213, and in the lumbar spine in 94 patients. There were 97 patients who underwent TES for more than two consecutive vertebrae. RESULTS: Major and minor perioperative complications were observed in 122 (39.7%) and 84 (27.4%) patients respectively. The breakdown of complications was as follows: bleeding more than 2,000 ml in 60 (19.5%) patients, hardware failure in 82 (26.7%), neurological in 46 (15.0%), surgical site infection in 23 (7.5%), wound dehiscence in 16 (5.2%), cerebrospinal fluid leakage in 45 (14.7%), respiratory in 52 (16.9%), cardiovascular in 11 (3.6%), digestive in 19 (6.2%)/ The mortality within two months of surgery was four (1.3%). The total number of complications per operation were 1.01 (SD 1.0) in the single vertebral resection group and 1.56 (SD 1.2) in the group with more than two vertebral resections. Cardiovascular and respiratory complications, along with hardware failure were statistically higher in the group who had more than two vertebrae resected. Also, in this group the amount of bleeding in patients with a lumbar lesion or respiratory complication in patients with a thoracic lesion, were statistically higher. Multivariate analysis showed that using a combined anterior and posterior approach, when more than two vertebral resections were significant independent factors. CONCLUSION: The characteristics of perioperative complications after TES were different depending on the extent and level of the tumour resection. In addition to preoperative clinical and pathological factors, it is therefore important to consider these factors in patients who undergo en bloc resection for spinal tumours. Cite this article: Bone Joint J 2021;103-B(5):976-983.

UV light killing efficacy of fluorescent protein-expressing cancer cells in vitro and in vivo.

We investigated the cell-killing efficacy of UV light on cancer cells expressing GFP in the nucleus and RFP in the cytoplasm (dual-color cells). After exposure to various doses of UVA, UVB, or UVC, apoptotic and viable cells were quantitated under fluorescence microscopy using dual-color 143B human osteosarcoma cells, HT-1080 human fibrosarcoma cells, Lewis lung carcinoma (LLC), and XPA-1 human pancreatic cancer cells in vitro. UV-induced cancer cell death was wave-length and dose dependent, as well as cell-line dependent. After UVA exposure, most cells were viable even when the UV dose was increased up to 200 J/m(2). With UVB irradiation, cell death was observed with irradiation at 50 J/m(2). For UVC, as little as 25 J/m(2) UVC irradiation killed approximately 70% of the 143B dual-color cells. This dose of UVB or UVA had almost no effect on the cancer cells. UV-induced cancer cell death varied among the cell lines. Cell death began about 4 h after irradiation and continued until 10 h after irradiation. UVC exposure also suppressed cancer cell growth in nude mice in a model of minimal residual cancer (MRC). No apparent side effects of UVC exposure were observed. This study opens up the possibility of UVC treatment for MRC after surgical resection.

Real-time imaging of single cancer-cell dynamics of lung metastasis.

We have developed a new in vivo mouse model to image single cancer-cell dynamics of metastasis to the lung in real-time. Regulating airflow volume with a novel endotracheal intubation method enabled controlling lung expansion adequate for imaging of the exposed lung surface. Cancer cells expressing green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm were injected in the tail vein of the mouse. The right chest wall was then opened in order to image metastases on the lung surface directly. After each observation, the chest wall was sutured and the air was suctioned in order to re-inflate the lung, in order to keep the mice alive. Observations have been carried out for up to 8 h per session and repeated up to six times per mouse thus far. The seeding and arresting of single cancer cells on the lung, accumulation of cancer-cell emboli, cancer-cell viability, and metastatic colony formation were imaged in real-time. This new technology makes it possible to observe real-time monitoring of cancer-cell dynamics of metastasis in the lung and to identify potential metastatic stem cells.

Polyneuropathy caused by cobalt-chromium metallosis after total hip replacement.

Although metal intoxication after arthroplasty causes various symptoms, polyneuropathy has never been the focus of clinical investigation. We report the case of a 56-year-old woman with metal neuropathy. She had metallosis after hip arthroplasty with a cobalt-chromium alloy prosthesis. She developed progressive sensory disturbance, hearing loss, and hypothyroidism. Sural nerve biopsy indicated axonopathy. After exchange arthroplasty, blood levels of cobalt and chromium decreased, and her symptoms improved. Cobalt or chromium can cause axonopathy.

Facilitated tendon-bone healing by local delivery of recombinant hepatocyte growth factor in rabbits.

PURPOSE: This study was performed to evaluate the therapeutic effect of hepatocyte growth factor (HGF) on tendon-bone healing in a rabbit model. METHODS: In adult rabbits the long digital extensor tendon was detached from the lateral femoral condyle, and the free end of the tendon was inserted into a tunnel drilled into the proximal tibial metaphysis. Cancellous bone obtained during drilling of the tibial hole was soaked in saline solution or solution containing 100-microg/mL human recombinant HGF and then transplanted into the bone tunnel. Junctional healing between the tendon and the bone was evaluated by histologic analysis and uniaxial load-to-failure testing at 2, 4, 6, 8, and 12 weeks after surgery. RESULTS: In the saline solution-treated control group, Sharpey-like fibers, which connected the tendon graft and the bone tissue, appeared 6 weeks after treatment. At 8 weeks after treatment, maturation of lamellar bone was seen, and at 12 weeks, the adhesion between tendon and bone appeared to be supported by indirect insertion of fibrocartilaginous tissue, wherein the border between the fibrocartilaginous tissue and tendon or bone was significant. In the HGF-treated group, the fibrous tissues were parallel to the load axis, and lamellar bone and Sharpey-like fibers appeared as early as 4 weeks after treatment. At 12 weeks, junctional tissue, characterized by a continuous 4-layer structure of bone, calcified cartilage, fibrocartilage, and tendon, was regenerated by a direct insertion. On biomechanical testing, the HGF-treated group had significantly better biomechanical properties than the control group at 2 and 4 weeks. The histologic improvement caused by HGF treatment was associated with the biomechanical improvement. CONCLUSIONS: Local administration of recombinant HGF promotes the adhesive healing process at the tendon-bone junction, both histologically and mechanically, after ligament reconstruction in a rabbit model. CLINICAL RELEVANCE: Application of HGF may be considered as a new therapeutic approach to accelerate healing and rehabilitation after ligament reconstruction.

Activation of the extracellular signal-regulated kinase signal pathway by light emitting diode irradiation.

Irradiation by light emitting diode (LED) promotes fibroblast proliferation and wound healing. However, its mechanism is still unknown. The purpose of this study was to clarify the mechanism of fibroblast proliferation by LED irradiation. Cultured NIH3T3 fibroblasts from normal mice were irradiated by LED with a center wavelength of 627 nm. LED irradiation was performed with an energy density of 4 J/cm(2), at subculture and 24 h later. The expression of several growth factors and their receptors was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR): platelet-derived growth factor (PDGF)-A, PDGF-B, and PDGF-C, transforming growth factor-beta (TGF-beta), basic fibroblast growth factor (bFGF), PDGF-alpha receptor, and TGF-beta receptor. Then, the activation of the extracellular signal-regulated kinase (ERK) pathway was examined by Western blotting with and without the PDGF receptor inhibitor. LED irradiation induced cell growth of NIH3T3 fibroblasts. The expression of PDGF-C had significantly increased in the irradiated group (P < 0.01). Although strong activation of the ERK pathway was observed in the irradiated group, its activation was completely suppressed by the PDGF receptor inhibitor. We concluded that LED irradiation promotes fibroblast proliferation by increasing autocrine production of PDGF-C and activating the ERK pathway through phosphorylation of the PDGF receptor.