Application of microwave surgical instrument to lung segmentectomy for small-sized lung cancer.

Objectives: For lung segmentectomy of small lung cancers, we used a microwave surgical instrument for lung parenchymal dissection mainly at the pulmonary hilum, which is difficult to handle with surgical staplers. This technique facilitated the insertion of staples. Methods: In total, 116 patients with cStage 0-1A3 non-small cell lung cancer who underwent lung segmentectomy were included in this study. We compared the perioperative factors of the group in which a microwave surgical instrument was used for dissection procedures, including lung parenchymal dissection at the pulmonary hilum, and peripheral intersegmental dissection was performed with surgical staplers (group M+S: N = 69), with those of the group in which parenchymal dissection was performed mainly with surgical staplers without using the microwave surgical instrument (group S: N = 47). Results: Although more complex segmentectomies were performed in the M+S group (P = .001), the number of staple cartridges (7 staple cartridges vs 8 staple cartridges, P = .005), the surgical times (179 vs 221 minutes, P < .0001), and the blood loss (5 mL vs 30 mL, P = .012) were significantly lower in the M+S group. The duration of chest tube placement was significantly shorter in the M+S group (P = .019), and postoperative complications of grade 2 or greater were significantly lower in the M+S group (P = .049). Conclusions: The effective use of the microwave surgical instrument combined with surgical staplers can simplify pulmonary hilar and intersegmental plane dissections not only for simple segmentectomy but also for complex segmentectomy, leading to favorable intraoperative and postoperative outcomes.

Negative pressure wound therapy for broncho-pleural fistula with collapsed lung.

We present a case of the broncho-pleural fistula with a collapsed lung that was developed 2 weeks after right lower lobectomy. The patient urgently underwent open-window thoracostomy. However, the residual lung remained collapsed. To expand the lung and close the broncho-pleural fistula, negative pressure wound therapy was initiated 20 days after the procedure. The lung expanded within a few days, and the residual thoracic cavity gradually contracted. Subsequently, 2.5 months later, the remaining thoracic cavity was successfully closed using omentoplasty. No recurrence of the broncho-pleural fistula was observed for 1 year. If the lung could be inflated to reduce dead space in the thoracic cavity, broncho-pleural fistula with collapsed lung may be treated with bronchial stump coverage and negative pressure wound therapy.

Impact of postoperative pleurodesis on pulmonary function after lung segmentectomy.

Objective: Pleurodesis is among several treatment strategies for postoperative alveolo-pleural fistula (APF) after lung resection. Accordingly, the present study aimed to determine the influence of pleurodesis on postoperative pulmonary function. Methods: Patients who underwent anatomical segmentectomy between January 2009 and March 2020 and pulmonary function tests 6 and 12 months after initial surgery were included in this study. Differences in pulmonary function decline between patients who did and did not undergo pleurodesis were compared. Results: Among the 319 patients included, 39 (12.2%) underwent pleurodesis. Among patients who did not receive pleurodesis, there were no difference in decline of vital capacity at 6 months (-13.7% ± 1.1% vs -11.2% ± 0.7%; P = .063) and 12 months (-10.7% ± 1.3% vs -9.5% ± 0.7%; P = .391) after surgery between patients who had APF on postoperative day 2 and those who did not. Patients who received pleurodesis had a significantly larger decline in vital capacity at 6 months (-19.4% ± 2.4% vs -13.7% ± 1.1%; P = .015) and 12 months (-16.2% ± 1.6% vs -10.7% ± 1.3%; P = .010) after surgery compared with those who had APF on postoperative day 2 and did not receive pleurodesis. There were no significant differences in decline of forced expiratory volume in 1 second. Conclusions: Pleurodesis negatively influenced postoperative vital capacity after lung segmentectomy. Although the clinical influence of this is unknown, careful consideration is needed before performing pleurodesis given its potential influence on postoperative pulmonary function.

Video-assisted thoracoscopic surgery using a three-dimensional thoracoscopic system as an educational tool for surgical trainees in general thoracic surgery.

OBJECTIVE: The clinical practice of safe and efficient surgery and professional development of general thoracic surgical trainee are both important issues for mentors. We investigated the usefulness of a three-dimensional (3D) endoscopic system application for lung cancer treatment as a tool for training surgical trainees. METHODS: Supervised by mentors, general thoracic surgical trainees were trained with video-assisted thoracoscopic surgery (VATS) for primary lung cancer using a 3D endoscopic system to enable them to become operators. Video clinics using 3D images were held weekly. The group using 3D endoscopic system (66 cases in the 3D-VATS group) was compared with the group using conventional two-dimensional (2D) thoracoscopic system (35 cases in the 2D-VATS group) to perform VATS lobectomies. RESULTS: There was no significant difference in operative time between both groups. However, the 3D-VATS group comprised significantly less experience than the 2D-VATS group. The intraoperative blood loss was significantly reduced for the 3D group (34 mL in the 3D-VATS group vs. 76 mL in the 2D-VATS group, P = 0.0007). There were no cases of conversion from VATS to open thoracotomy and intraoperative transfusion in either group. CONCLUSION: 3D-VATS and video clinics using 3D videos are useful training tools for general thoracic surgical trainees with little experience in open thoracotomy.

Differential roles of two DDX17 isoforms in the formation of membraneless organelles.

The RNA helicase, DDX17 is a member of the DEAD-box protein family. DDX17 has two isoforms: p72 and p82. The p82 isoform has additional amino acid sequences called intrinsically disordered regions (IDRs), which are related to the formation of membraneless organelles (MLOs). Here, we reveal that p72 is mostly localized to the nucleoplasm, while p82 is localized to the nucleoplasm and nucleoli. Additionally, p82 exhibited slower intranuclear mobility than p72. Furthermore, the enzymatic mutants of both p72 and p82 accumulate into the stress granules. The enzymatic mutant of p82 abolishes nucleolar localization of p82. Our findings suggest the importance of IDRs and enzymatic activity of DEAD-box proteins in the intracellular distribution and formation of MLOs.

Efficacy of complete video-assisted thoracoscopic surgery lobectomy using the three-dimensional endoscopic system for lung cancer.

OBJECTIVE: We aimed to investigate the efficacy of complete video-assisted thoracoscopic surgery (cVATS) lobectomy using the three-dimensional (3D) endoscopic system in patients with lung cancer and compare it with that of cVATS lobectomy using the conventional two-dimensional (2D) endoscopic system in former consecutive cases. METHODS: We retrospectively analyzed the prospectively collected database of patients with clinical stage I lung cancer who underwent cVATS lobectomy using the 3D endoscopic system; the patients who underwent surgery using the 2D endoscopic system were considered the historical control group. The operative and perioperative data were compared, and propensity-score matched comparisons were used to assess the potential impact of selection bias. RESULTS: We performed 189 cVATS lobectomies. Of these, 105 were performed using the 3D endoscopic system, while 84 were performed using the 2D endoscopic system. After matching, there was no significant difference in the preoperative factors between the two groups. The operation time was significantly shortened (P = 0.003), and the intraoperative blood loss was significantly reduced in the 3D group (P < 0.001). In particular, there was only one case of intraoperative hemorrhage of 201 mL or more in the 3D group, compared to 12 cases in the 2D group (P < 0.001). After matching, the intraoperative blood loss and operation time were significantly reduced in the 3D group. CONCLUSIONS: Our results showed that the 3D endoscopic system for cVATS lobectomy may be a useful surgical tool and switching to it from the 2D endoscopic system can be performed safely.

Knockdown of sphingomyelin synthase 2 inhibits osteoclastogenesis by decreasing RANKL expression in mouse primary osteoblasts.

Sphingomyelin is a major lipid of the plasma membrane and is enriched in microdomains of the plasma membrane that are critical for signal transduction. However, the function of sphingomyelin in the cell membrane of osteoblasts has not been clarified. Therefore, we examined how sphingomyelin synthase 2 (SMS2) affects osteoclast differentiation by osteoblasts. We knocked down the expression of SMS2 with siRNA targeting the Sgms2 gene in mouse primary osteoblasts. The effects of SMS2 knockdown in osteoblasts were examined using polymerase chain reaction and western blotting. The knockdown of SMS2 suppressed the formation of TRAP-positive multinucleated cells by co-culture of osteoblasts and bone marrow cells compared to the control. We found that receptor activator of nuclear factor κB ligand (RANKL) mRNA expression was significantly reduced by 1,25(OH)2D3 stimulation in SMS2 siRNA osteoblasts. The knockdown of SMS2 repressed the expression of retinoid-X-receptor-α (RXRα) regardless of 1,25(OH)2D3 stimulation. TRAP-positive multinucleated cell formation was significantly reduced by RXRα siRNA in osteoblasts in a co-culture system. These results suggest that SMS2 regulates osteoclast differentiation by inducing RANKL expression via RXRα.

Human Vγ9Vδ2 T cells show potent antitumor activity against zoledronate-sensitized OSCC cell lines.

PURPOSE: Vγ9Vδ2 T cells exhibit potent antitumor effects against multiple types of tumors in preclinical models. In the present study, we examined whether human Vγ9Vδ2 T cells can be effective against oral squamous cell carcinoma (OSCC) cell lines in vitro because the interaction between OSCC and Vγ9Vδ2 T cells has not been explored previously. METHODS: Eight OSCC cell lines were analyzed for their expression of ligands that potentially activate Vγ9Vδ2 T cells. Vγ9Vδ2 T cells were expanded in vitro from peripheral blood mononuclear cells (PBMCs) using zoledronate and IL-2. Expanded Vγ9Vδ2 T cells were tested for IFNγ production and cytotoxicity in response to zoledronate-treated OSCC cell lines. Flow cytometry was used to obtain and analyze data. RESULTS: All OSCC cell lines expressed CD277. The cell lines also expressed at least one type of NKG2D ligand. Zoledronate-treated OSCC cell lines induced IFNγ expression in Vγ9Vδ2 T cells. We thus found that Vγ9Vδ2 T cells efficiently kill zoledronate-sensitized OSCC cell lines. CONCLUSIONS: We found that zoledronate-treated OSCC cell lines are effectively killed by Vγ9Vδ2 T cells. Our results indicate that developing Vγ9Vδ2 T cell-based immunotherapy will be promising in treating patients with OSCC.

Cytokine-mediated activation of human ex vivo-expanded Vγ9Vδ2 T cells.

Vγ9Vδ2 T cells, the major subset of the human peripheral blood γδ T-cell, respond to microbial infection and stressed cells through the recognition of phosphoantigens. In contrast to the growing knowledge of antigen-mediated activation mechanisms, the antigen-independent and cytokine-mediated activation mechanisms of Vγ9Vδ2 T cells are poorly understood. Here, we show that interleukin (IL) -12 and IL-18 synergize to activate human ex vivo-expanded Vγ9Vδ2 T cells. Vγ9Vδ2 T cells treated with IL-12 and IL-18 enhanced effector functions, including the expression of IFN-γ and granzyme B, and cytotoxicity. These enhanced effector responses following IL-12 and IL-18 treatment were associated with homotypic aggregation, enhanced expression of ICAM-1 and decreased expression of the B- and T-lymphocyte attenuator (BTLA), a co-inhibitory receptor. IL-12 and IL-18 also induced the antigen-independent proliferation of Vγ9Vδ2 T cells. Increased expression of IκBζ, IL-12Rß2 and IL-18Rα following IL-12 and IL-18 stimulation resulted in sustained activation of STAT4 and NF-κB. The enhanced production of IFN-γ and cytotoxic activity are critical for cancer immunotherapy using Vγ9Vδ2 T cells. Thus, the combined treatment of ex vivo-expanded Vγ9Vδ2 T cells with IL-12 and IL-18 may serve as a new strategy for the therapeutic activation of these cells.

[Abdominoperineal Resection for Anal Metastasis of Rectal Cancer].

Anal metastasis of colorectal cancer is rare, and no standardized effective therapeutic strategy exists. We report a case of abdominoperineal resection for anal metastasis of rectal cancer. A 65-year-old man underwent laparoscopic low anterior resection for rectal cancer in August 2013. Histopathological examination revealed a moderately differentiated adenocarcinoma( tub2, pSS, ly3, v2, pN1, H0, P0, M0, Stage III a, Cur A). In February 2015, he complained of anal discomfort, and tumor markers were elevated. Enhanced CT revealed a 15-mm high-density solid tumor in the anal canal. The results of needle biopsy indicated a moderately differentiated adenocarcinoma. This tumor was suspected to be metastasis from rectal cancer, and we performed abdominoperineal resection. Histopathological examination revealed a moderately differentiated adenocarcinoma, which was the same histological type as the primary rectal cancer and was covered with normal anal epithelium. Collectively, the findings indicated anal metastasis from rectal cancer. The patient is alive without recurrence for 18 months after resection. Anal metastasis should be considered as a differential diagnosis in patients with anal discomfort who have a history of colon/rectal cancer. Abdominoperineal resection may be an effective treatment modality for this condition.

Nucleolar scaffold protein, WDR46, determines the granular compartmental localization of nucleolin and DDX21.

The nuclear scaffold is an insoluble nuclear structure that contributes to the inner nuclear organization. In this study, we showed that one of the nuclear scaffold proteins, WDR46, plays a role as a fundamental scaffold component of the nucleolar structure. WDR46 is a highly insoluble nucleolar protein, and its subcellular localization is dependent on neither DNA nor RNA. The N- and C-terminal regions of WDR46 are predicted to be intrinsically disordered, and both regions are critical for the nucleolar localization of WDR46 and the association with its binding partners. When WDR46 was knocked down, two of its binding partners, nucleolin and DDX21 (involved in 18S rRNA processing), were mislocalized from the granular component to the edges of the nucleoli, whereas other binding partners, NOP2 and EBP2 (involved in 28S rRNA processing), were not affected. This is because the proper recruitment of nucleolin and DDX21 to the nucleoli in daughter cells after cell division is ensured by WDR46. These findings suggest a structural role for WDR46 in organizing the 18S ribosomal RNA processing machinery. This role of WDR46 is enabled by its interaction property via intrinsically disordered regions.