Downregulation of Histone H3.3 Induces p53-Dependent Cellular Senescence in Human Diploid Fibroblasts.

Cellular senescence is an irreversible growth arrest that acts as a barrier to cancer initiation and progression. Histone alteration is one of the major events during replicative senescence. However, little is known about the function of H3.3 in cellular senescence. Here we found that the downregulation of H3.3 induced growth suppression with senescence-like phenotypes such as senescence-associated heterochromatin foci (SAHF) and ß-galactosidase (SA-ß-gal) activity. Furthermore, H3.3 depletion induced senescence-like phenotypes with the p53/p21-depedent pathway. In addition, we identified miR-22-3p, tumor suppressive miRNA, as an upstream regulator of the H3F3B (H3 histone, family 3B) gene which is the histone variant H3.3 and replaces conventional H3 in active genes. Therefore, our results reveal for the first time the molecular mechanisms for cellular senescence which are regulated by H3.3 abundance. Taken together, our studies suggest that H3.3 exerts functional roles in regulating cellular senescence and is a promising target for cancer therapy.

Full-thickness chest wall resection for malignant chest wall tumors and postoperative problems.

Background: Chest wall malignant tumor (including primary and metastatic lesions) is rare, representing less than 5% of all thoracic malignancies. Local control of chest wall malignancies requires wide resection with tumor-free margins. These requirements increase the risk of thoracic cavity failure and subsequent pulmonary failure. The restoration strategy for chest wall defects comprises chest wall reconstruction and soft-tissue coverage. Various reconstruction methods have been used, but both evidence and guidelines for chest wall reconstruction remain lacking. The purposes of this study were to collate our institutional experience, evaluate the outcomes of full-thickness chest wall resection and reconstruction for patients with chest wall malignant tumor, and identify problems in current practice for chest wall reconstruction with a focus on local control, complications, pulmonary function and scoliosis. Methods: Participants comprised 30 patients with full-thickness chest wall malignant tumor who underwent chest wall resection and reconstruction between 1997 and 2021 in Mie University Hospital. All patients underwent chest wall resection of primary, recurrent or metastatic malignant tumors. A retrospective review was conducted for 32 operations. Results: Recurrence was observed after 5 operations. Total 5-year recurrence-free survival (RFS) rate was 79.3%. Diameter ≥5 cm was significantly associated with poor RFS. The postoperative complication rate was 18.8%. Flail chest was observed with resection of ≥3 ribs in anterior and lateral resections or with sternum resection without polyethylene methylmethacrylate reconstruction. Postoperative EFV1.0% did not show any significant decrease. Postoperative %VC decreased significantly with resection of ≥4 ribs or an area of >70 cm2. Postoperative scoliosis was observed in 8 of 28 patients. Posterior resection was associated with a high prevalence of scoliosis (88.9%). Conclusion: With chest wall reconstruction, risks of pulmonary impairment, flail chest and scoliosis were significantly increased. New strategies including indications for rigid reconstruction are needed to improve the outcomes of chest wall reconstruction.

Two different methods of bronchial dissection and coverage in robotic bilobectomy for advanced lung cancer.

INTRODUCTION: Due to its many technical advantages, the scope of robot-assisted thoracic surgery (RATS) is expanding to include extended pulmonary resection. Among such procedures, right bilobectomy is one with a high risk of inducing development of a bronchial stump fistula. MATERIALS AND SURGICAL TECHNIQUE: The pericardial fat pad case involved a 71-year-old man with a 31-mm adenocarcinoma in the right lung that had progressed to the intermediate bronchus. During lower bilobectomy, to confirm the tumor margin, an L-shaped stapler was used with stapling only at the oral side, and the bronchus was cut using a scalpel blade grasped with robot forceps. After confirming a negative stump, the pericardial fat was collected at the pedicle and sewn onto the stump. The intercostal muscle (ICM) flap case involved a 61-year-old man with a 16-mm nodule shadow in the lower lobe of his lung and swollen #11i and 7 lymph nodes. Intraoperatively, the #7 lymph node was diagnosed as non-small-cell lung cancer by frozen sections, and lower bilobectomy was performed. The bronchus was divided using a stapler with a green cartridge, and the ICM flap was harvested by changing the direction of the camera to a look-up view and positioning the camera at the 5th intercostal site. His numeric rating score (NRS) at 30 and 90 days post-surgery was 2 and 0, respectively. DISCUSSION: Our RATS technique was useful for harvesting the ICM flap. More cases should be accumulated to extend the surgical indication for RATS.

Research on Werner Syndrome: Trends from Past to Present and Future Prospects.

A rare and autosomal recessive premature aging disorder, Werner syndrome (WS) is characterized by the early onset of aging-associated diseases, including shortening stature, alopecia, bilateral cataracts, skin ulcers, diabetes, osteoporosis, arteriosclerosis, and chromosomal instability, as well as cancer predisposition. WRN, the gene responsible for WS, encodes DNA helicase with a 3' to 5' exonuclease activity, and numerous studies have revealed that WRN helicase is involved in the maintenance of chromosome stability through actions in DNA, e.g., DNA replication, repair, recombination, and epigenetic regulation via interaction with DNA repair factors, telomere-binding proteins, histone modification enzymes, and other DNA metabolic factors. However, although these efforts have elucidated the cellular functions of the helicase in cell lines, they have not been linked to the treatment of the disease. Life expectancy has improved for WS patients over the past three decades, and it is hoped that a fundamental treatment for the disease will be developed. Disease-specific induced pluripotent stem (iPS) cells have been established, and these are expected to be used in drug discovery and regenerative medicine for WS patients. In this article, we review trends in research to date and present some perspectives on WS research with regard to the application of pluripotent stem cells. Furthermore, the elucidation of disease mechanisms and drug discovery utilizing the vast amount of scientific data accumulated to date will be discussed.

Tenascin C in radiation-induced lung damage: Pathological expression and serum level elevation.

Radiation-induced lung damage (RILD) is a critical problem in lung cancer radiotherapy, and it is difficult to predict its severity. Although no biomarkers for RILD have been established, tenascin C (TNC) is an extracellular matrix glycoprotein involved in the remodeling of damaged tissues and has been implicated in inflammation and fibrosis. We report the unique case of a 36-year-old man with adenocarcinoma of the lung, Union for International Cancer Control stage IIIB, who was treated with radiotherapy before lung surgery. The surgical specimen showed histopathological expression of TNC in the region where radiation pneumonitis was observed radiographically. Serum TNC levels were elevated after radiotherapy. In this case, TNC is suggested to be implicated in RILD and may be a potential candidate as a biomarker for the onset and severity of the condition.

Spontaneous pneumothorax in a 17-year-old male patient with multiple exostoses: A case report and review of the literature.

BACKGROUND: Multiple exostoses generally develop in the first decade of life. They most frequently arise from the distal femur, proximal tibia, fibula, and proximal humerus. Costal exostoses are rare, contributing to 1%-2% of all exostoses in hereditary multiple exostoses (HME). They are usually asymptomatic, but a few cases have resulted in severe thoracic injuries. Pneumothorax caused by costal exostoses is rare, with only 13 previously reported cases. We report a new case of pneumothorax caused by costal exostoses. CASE SUMMARY: A 17-year-old male with HME underwent surgery for removal of exostoses around his right knee. Four months following the operation, he felt chest pain when he was playing the trumpet; however, he did not stop playing for a week. He was referred to our hospital with a chief complaint of chest pain. The computed tomography (CT) scan revealed right pneumothorax and multiple exostoses in his right ribs. The CT scan also revealed visceral pleura thickness and damaged lung tissues facing the exostosis of the seventh rib. We diagnosed that exostosis of the seventh rib induced pneumothorax. Costal exostosis resection was performed by video-assisted thoracoscopic surgery (VATS) 2 wk after the onset. The patient's postoperative course was uneventful, and there was no recurrence of pneumothorax for 2 years. CONCLUSION: Costal exostoses causing thoracic injuries should be resected regardless of age. VATS must be considered in cases with apparently benign and relatively small exostoses or HME.

Endobronchial brachytherapy as definitive treatment for endobronchial metastasis after surgery of non-small cell lung cancer.

BACKGROUND: Endobronchial metastasis is a very rare type of recurrence after lung cancer surgery. Surgical intervention may be difficult to perform due to the postoperative reduction in the activities of daily living (ADL) and the invasiveness associated with redo surgery. In such cases, endobronchial brachytherapy (EBBT) plays an important role not only as a palliative treatment, but also as a definitive treatment with curative intent. CASE PRESENTATION: Three men (64, 69, and 74 years old) underwent combination therapy of external beam radiation therapy (EBRT) and EBBT for endobronchial metastasis after lobectomy of stage I-II non-small cell lung cancer (NSCLC): 2 cases of squamous cell carcinoma and 1 of adenocarcinoma. We used a special source-centralizing applicator for EBBT to avoid eccentric distribution of the radiation dose. Follow-up was considered to start from the end of brachytherapy. None of our patients experienced severe adverse events, and none needed extensive outpatient treatment. Local control was achieved in all cases by a bronchoscopic evaluation. All patients were alive after 31, 38, and 92 months of follow-up, respectively. In the adenocarcinoma patient, two metastases to the lung were discovered 3 years after EBBT, and the patient underwent partial wedge resection. CONCLUSIONS: EBBT may be a promising treatment with curative intent for endobronchial metastasis after surgery of NSCLC.

Substrate stiffness modulates endothelial cell function via the YAP-Dll4-Notch1 pathway.

Endothelial cells adapt their functions as a consequence of sensing extracellular substrate stiffness; these alterations allow them to maintain their vascular structure and function. Substrate stiffness-mediated yes-associated protein 1 (YAP) activation plays an important role in mechano-transduction and pro-angiogenic phenotype of endothelial cells, and Delta-like ligand 4 (Dll4)-Notch1 signaling is closely related to angiogenesis; however, the impact of substrate stiffness-mediated interrelation of these pathways on endothelial cell functions remains elusive. We confirmed that endothelial cells on softer substrates not only elongate cellular aspects but also attenuate YAP activation compared to cells on stiffer substrates. Endothelial cells on softer substrates also upregulate the vascular endothelial growth factor receptor 1 (VEGFR1) and VEGFR2 mRNA expression that is enhanced by VEGF stimulation. We determined that endothelial cells on softer substrates increased Dll4 expression, but not Notch1 expression, via YAP signaling. Moreover, endothelial cells on soft substrates induced not only VEGFRs upregulation but also suppression of pro-inflammatory interleukin-6 and plasminogen activator inhibitor-1 mRNA expression and the facilitation of anti-coagulant thrombomodulin and pro-coagulant tissue factor mRNA expression. Our results suggest that endothelial cells activate the YAP-Dll4-Notch signaling pathway in response to substrate stiffness and dictate cellular function.

A founder variant in the South Asian population leads to a high prevalence of FANCL Fanconi anemia cases in India.

Fanconi anemia (FA) is a rare genetic disorder characterized by bone marrow failure, predisposition to cancer, and congenital abnormalities. FA is caused by pathogenic variants in any of 22 genes involved in the DNA repair pathway responsible for removing interstrand crosslinks. FANCL, an E3 ubiquitin ligase, is an integral component of the pathway, but patients affected by disease-causing FANCL variants are rare, with only nine cases reported worldwide. We report here a FANCL founder variant, anticipated to be synonymous, c.1092G>A;p.K364=, but demonstrated to induce aberrant splicing, c.1021_1092del;p.W341_K364del, that accounts for the onset of FA in 13 cases from South Asia, 12 from India and one from Pakistan. We comprehensively illustrate the pathogenic nature of the variant, provide evidence for a founder effect, and propose including this variant in genetic screening of suspected FA patients in India and Pakistan, as well as those with ancestry from these regions of South Asia.

Therapeutic strategy for acute pleural empyema: comparison between retrospective study and prospective study.

OBJECTIVES: The purpose of this study is to investigate the efficiency of therapeutic strategy for acute pleural empyema. METHODS: We retrospectively reviewed 121 acute empyema patients and evaluated the therapeutic strategy for acute pleural empyema. Then, we prospectively reviewed 114 acute pleural empyema patients based on the strategy. RESULTS: The duration from onset to hospitalization in our hospital is statistically shorter, and the mortality and the rate of stage 3 empyema patients are lower in the prospective study group (PSG) than in the retrospective study group (RSG). Retrospective study and prospective study found that surgical group (SG) had more favorable outcomes than non-surgical group (NSG). Although antibiotic treatment duration, hospital stay, and entire mortality were comparable in NSG of both study groups, mortality of patients with PS grade 4 was significantly lower in PSG. SG in PSG had more favorable outcomes than that in RSG, such as antibiotic treatment duration, hospital stay, complication, and mortality. CONCLUSIONS: The good outcomes may be mainly caused by shorter duration from onset to hospitalization and shorter duration from hospitalization to operation. Operative management is an effective procedure for selected patients, and it is important to refer for thoracic surgical consultation earlier.

Thoracoscopic mediastinal tumor resection by subxiphoid approach-dual port thymectomy plus one (DPT+1).

Thoracoscopic subxiphoid approaches, such as the single-port thymectomy (SPT) and dual-port thymectomy (DPT) approaches have been demonstrated to have several advantages compared with the traditional median sternotomy approach or the bilateral or hemilateral video-assisted thoracoscopic (VATS) approach. However, SPT and DPT are technically demanding for novice surgeons since they require precise concomitant manipulation of surgical instruments and the thoracoscope within the same port, without interference. To overcome these limitations, we have developed a new method, termed DPT plus one (DPT+1), to facilitate separation of the surgical access ports and camera port by adding another intercostal port to the DPT approach. Our method is easy and safe not only for simple mediastinal resection but also for extended thymectomy.

Introduction of thoracoscopic surgery for congenital pulmonary airway malformation in infants: review of 13 consecutive surgical cases.

BACKGROUND: Although complete video-assisted thoracic surgery (C-VATS) has been demonstrated to have several advantages compared with conventional thoracotomy, there are few reports on the clinical feasibility of C-VATS for CPAM in infants. METHODS: We retrospectively evaluated 13 consecutive patients (neonates 4; infants 9) surgically treated for congenital pulmonary airway malformation (CPAM) from 1 January 2008 to 31 March 2017. RESULTS: In the group of neonates, all 4 cases were prenatally diagnosed and they underwent semi-emergent surgery after birth due to respiratory failure. In the group of 9 infants, 5 cases were prenatally diagnosed and 4 cases were diagnosed at age >2.5 years due to symptoms associated with pulmonary cystic infection. Pulmonary resection consisted of the following: 8 lobectomies, 1 segmentectomy, 2 wedge resection, 1 fractionated lung resection and 1 lobectomy with segmentectomy. Overall, there were 9 thoracotomy and 4 thoracoscopic surgeries. Mean operation time was 162 min (range, 67-290 min) and blood loss was 21 mL (range, 0-74 mL) on average. There were no complications such as thoracic deformity or respiratory failure, however in 2 of those who underwent segmentectomy the cystic remnant remained. No statistically significant differences were observed between the thoracotomy Group and C-VATS group in terms of age and height at intervention, operation time, blood loss, postoperative day of drain removal, and length of hospital stay after surgery. However, only the average body weight was heavier in C-VATS group (P=0.03). CONCLUSIONS: Since early surgical resection of asymptomatic CPAM is often recommended for the prevention of infections and the development of lung malignancy, we recommend performing surgery after the age of 1 year if the patient's condition is stable. Furthermore, C-VATS lobectomy may be feasible if they are older than 18 months or weigh more than 10 kg.

Primary racemose hemangioma with bronchial-pulmonary arterial fistula.

Primary racemose hemangioma with bronchial-pulmonary arterial fistula is a very rare abnormality. We herein report an asymptomatic case of primary racemose hemangioma with no significant size change in 5 years.

Prolonged intravenous indocyanine green visualization by temporary pulmonary vein clamping: real-time intraoperative fluorescence image guide for thoracoscopic anatomical segmentectomy.

The real-time endoscopic colour and fluorescence-merged imaging system, using intravenous injection of indocyanine green (ICG), allows a clear surgical view, which facilitates identification of the pulmonary inter-segmental plane in thoracoscopic surgery. However, the staining time is too short to mark and cut the intersegmental plane, because the mean washout time of ICG is only a few minutes in the clinical setting. To overcome this limitation, we have developed a new technique for prolongation of ICG staining time. The technique consists of 2 simple steps. First, we cut the targeted segmental artery, vein and bronchus. Second, ICG is injected intravenously, followed by temporary clamping of the pulmonary vein of entire lobe, including the segments. Our technique may not only offer prolonged washout time for marking the surface of the lung but also facilitate identification of precise intersegmental plane to be cut.

Magnetic Targeted Delivery of Induced Pluripotent Stem Cells Promotes Articular Cartilage Repair.

Cartilage regeneration treatments using stem cells are associated with problems due to the cell source and the difficulty of delivering the cells to the cartilage defect. We consider labeled induced pluripotent stem (iPS) cells to be an ideal source of cells for tissue regeneration, and if iPS cells could be delivered only into cartilage defects, it would be possible to repair articular cartilage. Consequently, we investigated the effect of magnetically labeled iPS (m-iPS) cells delivered into an osteochondral defect by magnetic field on the repair of articular cartilage. iPS cells were labeled magnetically and assessed for maintenance of pluripotency by their ability to form embryoid bodies in vitro and to form teratomas when injected subcutaneously into nude rats. These cells were delivered specifically into cartilage defects in nude rats using a magnetic field. The samples were graded according to the histologic grading score for cartilage regeneration. m-iPS cells differentiated into three embryonic germ layers and formed teratomas in the subcutaneous tissue. The histologic grading score was significantly better in the treatment group compared to the control group. m-iPS cells maintained pluripotency, and the magnetic delivery system proved useful and safe for cartilage repair using iPS cells.

Inhibition of telomerase causes vulnerability to endoplasmic reticulum stress-induced neuronal cell death.

Endoplasmic reticulum (ER) stress is implicated in several diseases, such as cancer and neurodegenerative diseases. In the present study, we investigated the possible involvement of telomerase in ER stress-induced cell death. ER stress-induced cell death was ameliorated in telomerase reverse transcriptase (TERT) over-expressing MCF7 cells (MCF7-TERT cell). Telomerase specific inhibitor, BIBR1532, reversed the inhibitory effect of TERT on ER stress-induced cell death in MCF7-TERT cells. These findings suggest that BIBR1532 may specifically inhibit telomerase activity, thereby inducing cell death in ER stress-exposed cells. TERT was expressed in the SH-SY5Y neuroblastoma cell line. To analyze the possible involvement of telomerase in ER stress-induced neuronal cell death, we treated SH-SY5Y neuroblastoma cells with BIBR1532 and analyzed ER stress-induced cell death. We found that BIBR1532 significantly enhanced the ER stress-induced neuronal cell death. These findings suggest that inhibition of telomerase activity may enhance vulnerability to neuronal cell death caused by ER stress.

The Outcomes of a Limited Resection for Non-Small Cell Lung Cancer Based on Differences in Pathology.

OBJECTIVE: A precise preoperative diagnosis of in situ or minimally invasive carcinoma may identify patients who can be treated by limited resection. Although some clinical trials of limited resection for lung cancer have started, it will take a long time before the results will be published. We have already reported a large-scale study of limited resection. We herein report the data for a subclass analysis according to differences in pathology. METHODS: Data from multiple institutions were collected on 1710 patients who had undergone limited resection (segmentectomy or wedge resection) for cT1N0M0 non-small cell carcinoma. The disease-free survival (DFS) and recurrence-free proportion (RFP) were analyzed. Small cell carcinomas and carcinoid tumors were excluded from this analysis. Adenocarcinomas were sub-classified into four groups using two factors, the ratio of consolidation to the tumor diameter (C/T) and the tumor diameter alone. RESULTS: The median patient age was 64 (20-75) years old. The mean maximal diameter of the tumors was 1.5 ± 0.5 cm. The DFS and RFP at 5 years based on the pathology were 92.2 and 94.7 % in adenocarcinoma (n = 1575), 76.3 and 82.4 % in squamous cell carcinoma (SqCC) (n = 100), and 73.6 and 75.9 % in patients with other tumors (n = 35). The prognosis of adenocarcinoma in both groups A (C/T ≤0.25 and tumor diameter ≤2.0 cm) and B (C/T ≤0.25 and tumor diameter >2.0 cm) was good. In SqCC, only segmentectomy was a favorable prognostic factor. In the groups with other pathologies, large cell carcinomas were worse in prognosis (the both DFS and RFP: 46.3 %). CONCLUSION: Knowing the pathological diagnosis is important to determine the indications for limited resection. Measurement of the tumor diameter and C/T was useful to determine the indications for limited resection for adenocarcinoma. Limited resection for adenocarcinomas is similar with a larger resection, while the technique should be performed with caution in squamous cell carcinoma and other pathologies.

Early and late recurrence after intentional limited resection for cT1aN0M0, non-small cell lung cancer: from a multi-institutional, retrospective analysis in Japan.

OBJECTIVES: In 2015, we reported the outcomes of patients undergoing intentional limited resection (ILR) for non-small-cell lung cancer (NSCLC) from a retrospective, multi-institutional large database in Japan. Here, we analyse the clinicopathological characteristics of the patients extracted from this database with late recurrence and compare them with those with early recurrence. METHODS: Of 1538 patients in the database with cT1aN0M0 NSCLC, 92 (6%) had recurrence. In this study, early recurrence was defined as recurrence within 5 years and late recurrence as recurrence beyond 5 years after surgery. We compared the clinicopathological characteristics and post-recurrence survival (PRS) between patients with early and late recurrence. RESULTS: Of the 92 patients with recurrence, 21 (23%) had late recurrence. Compared with the early recurrence group, there were significantly more adenocarcinomas and local recurrences in the late recurrence group (P = 0.04 for both). The 3- and 5-year PRS rates were 53 and 24%, respectively, and the median PRS period was 38 months. There were no significant differences in the PRS curves between patients with early and late recurrence (P = 0.12). Only 3 patients (0.2%) had recurrence more than 10 years after ILR. Of the 21 late-recurrence patients, 17 (81%) had tumours with a consolidation/tumour ratio (CTR) >0.25. CONCLUSIONS: Late recurrence occurred in 21 (23%) of 92 patients with recurrence after ILR for cT1aN0M0 NSCLC. Late recurrence was more likely to involve adenocarcinoma and local recurrence. It is thus considered reasonable to follow patients with a CTR >0.25 for 10 years after ILR.

Mutations in the gene encoding the E2 conjugating enzyme UBE2T cause Fanconi anemia.

Fanconi anemia (FA) is a rare genetic disorder characterized by genome instability, increased cancer susceptibility, progressive bone marrow failure (BMF), and various developmental abnormalities resulting from the defective FA pathway. FA is caused by mutations in genes that mediate repair processes of interstrand crosslinks and/or DNA adducts generated by endogenous aldehydes. The UBE2T E2 ubiquitin conjugating enzyme acts in FANCD2/FANCI monoubiquitination, a critical event in the pathway. Here we identified two unrelated FA-affected individuals, each harboring biallelic mutations in UBE2T. They both produced a defective UBE2T protein with the same missense alteration (p.Gln2Glu) that abolished FANCD2 monoubiquitination and interaction with FANCL. We suggest this FA complementation group be named FA-T.

Werner Syndrome-specific induced pluripotent stem cells: recovery of telomere function by reprogramming.

Werner syndrome (WS) is a rare human autosomal recessive premature aging disorder characterized by early onset of aging-associated diseases, chromosomal instability, and cancer predisposition. The function of the DNA helicase encoded by WRN, the gene responsible for WS, has been studied extensively. WRN helicase is involved in the maintenance of chromosome integrity through DNA replication, repair, and recombination by interacting with a variety of proteins associated with DNA repair and telomere maintenance. The accelerated aging associated with WS is reportedly caused by telomere dysfunction, and the underlying mechanism of the disease is yet to be elucidated. Although it was reported that the life expectancy for patients with WS has improved over the last two decades, definitive therapy for these patients has not seen much development. Severe symptoms of the disease, such as leg ulcers, cause a significant decline in the quality of life in patients with WS. Therefore, the establishment of new therapeutic strategies for the disease is of utmost importance. Induced pluripotent stem cells (iPSCs) can be established by the introduction of several pluripotency genes, including Oct3/4, Sox2, Klf4, and c-myc into differentiated cells. iPSCs have the potential to differentiate into a variety of cell types that constitute the human body, and possess infinite proliferative capacity. Recent studies have reported the generation of iPSCs from the cells of patients with WS, and they have concluded that reprogramming represses premature senescence phenotypes in these cells. In this review, we summarize the findings of WS patient-specific iPSCs (WS iPSCs) and focus on the roles of telomere and telomerase in the maintenance of these cells. Finally, we discuss the potential use of WS iPSCs for clinical applications.