Migration Of Head Research Articles

CDK1 Promotes Epithelial-Mesenchymal Transition and Migration of Head and Neck Squamous Carcinoma Cells by Repressing ∆Np63α-Mediated Transcriptional Regulation.

∆Np63α is a key transcription factor overexpressed in types of squamous cell carcinomas (SCCs), which represses epithelial–mesenchymal transition (EMT) and cell migration. In this study, we found that CDK1 phosphorylates ∆Np63α at the T123 site, impairing its affinity to the target promoters of its downstream genes and its regulation of them in turn. Database analysis revealed that CDK1 is overexpressed in head and neck squamous cell carcinomas (HNSCCs), especially the metastatic HNSCCs, and is negatively correlated with overall survival. We further found that CDK1 promotes the EMT and migration of HNSCC cells by inhibiting ∆Np63α. Altogether, our study identified CDK1 as a novel regulator of ΔNp63α, which can modulate EMT and cell migration in HNSCCs. Our findings will help to elucidate the migration mechanism of HNSCC cells.

Paper 90: Histopathology of Rotator Cuff Tendons in Elderly Patients with Glenohumeral Arthritis without Cuff Tears

Paper 90: Histopathology of Rotator Cuff Tendons in Elderly Patients with Glenohumeral Arthritis without Cuff Tears

Shoulder kinematics and muscle activity following latissimus dorsi transfer for massive irreparable posterosuperior rotator cuff tears in shoulders with pseudoparalysis.

The aim of this study was to evaluate the thoracohumeral (TH) and glenohumeral (GH) motion with muscle activity after latissimus dorsi transfer (LDT) in a shoulder with a massive irreparable posterosuperior rotator cuff tear (MIRT) and pseudoparalysis compared with the asymptomatic contralateral shoulder (ACS). We recruited and evaluated 13 patients after LDT in a shoulder with preoperative clinical pseudoparalysis and an MIRT on magnetic resonance imaging, with a minimum follow-up period of 1 year, and with a Hamada stage of 3 or less. Three-dimensional electromagnetic tracking was used to assess shoulder active range of motion in both the LDT shoulder and the ACS. The maximal active elevation of the shoulder (MAES) was assessed and consisted of forward flexion, scapular abduction, and abduction in the coronal plane. Maximal active internal rotation and external rotation were assessed separately. Surface electromyography (EMG) was performed to track activation of the latissimus dorsi (LD) and deltoid muscles during shoulder motion. EMG was scaled to its maximal isometric voluntary contraction recorded in specified strength tests. In MAES, TH motion of the LDT shoulder was not significantly different from that of the ACS (F1,12=1.174, P=.300) but the GH contribution was significantly lower in the LDT shoulder for all motions (F1,12=11.230, P=.006). External rotation was significantly greater in the ACS (26°±10° in LDT shoulder vs. 42°±11° in ACS, P<.001). The LD percentage EMG maximum showed no significant difference between the LDT shoulder and ACS during MAES (F1,11=0.005, P=.946). During maximal active external rotation of the shoulder, the LDT shoulder showed a higher percentage EMG maximum than the ACS (3.0%±2.9% for LDT shoulder vs. 1.2%±2.0% for ACS, P=.006). TH motion improved after LDT in an MIRT with pseudoparalysis and was not different from the ACS except for external rotation. However, GH motion was significantly lower after LDT than in the ACS in active-elevation range of motion. The LD was active after LDT but not more than in the ACS except for active external rotation, which we did not consider relevant as the activity did not rise above 3% EMG maximum. The favorable clinical results of LDT do not seem to be related to a change in LD activation and might be explained by its effect in preventing proximal migration of the humeral head in active elevation.

Cancer-Associated Fibroblasts Promote Tumor Aggressiveness in Head and Neck Cancer through Chemokine Ligand 11 and C-C Motif Chemokine Receptor 3 Signaling Circuit

Simple SummaryCertain tumor aggressiveness-associated mediators from cancer-associated fibroblasts (CAFs) in tumor microenvironment have been reported. Using gene expression analysis, we identified that CAFs overexpress Chemokine ligand 11 (CCL11), which is associated with tumor migration and invasion, increased expression of cancer stem cell properties, and induction of the epithelial-to-mesenchymal transition. Neutralization of CAF-induced CCL11 reversed the aggressive phenotype of cancer cells. Based on the immunohistochemical staining of clinical samples, we found that increased co-expression of CCL11 and its receptor, C-C Motif Chemokine Receptor 3 (CCR3), was associated with poor overall survival. Our results suggest that targeting CCL11-CCR3 signaling is a potential therapeutic strategy for patients with aggressive head and neck cancer. The tumor microenvironment (TME) plays a crucial role in tumor progression. One of its key stromal components, cancer-associated fibroblasts (CAFs), may crosstalk with cancer cells by secreting certain cytokines or chemokines. However, which important mediator(s) are released by CAFs, and the underlying molecular mechanism, remain largely unknown. In the present study, we isolated patient-derived CAFs and normal fibroblasts (NFs). Using microarray analysis, we detected chemokine ligand 11 (CCL11) overexpression in CAFs compared to NFs. CCL11 administration promoted the migration and invasion of head and neck cancer (HNC) cells with enhanced cancer stem cell-like properties and induction of epithelial-to-mesenchymal transition. Furthermore, neutralization of CCL11 activity reversed the aggressive phenotype of CAF-induced cancer cells. Confocal microscopy showed colocalization of CCL11 and CC chemokine receptor 3 (CCR3) on HNC cells. Moreover, immunohistochemical analysis of clinical samples from 104 patients with HNC showed that expression of CCL11 and CCR3 were significantly correlated with poor overall survival (p = 0.003 and 0.044, respectively). Collectively, CCL11 expressed on CAFs promotes HNC invasiveness, and neutralization of CCL11 reverses this effect. We propose that the CCL11/CCR3 signaling circuit is a potential target for optimizing therapeutic strategies against HNC.

Does Migration Push Exit from Agriculture in Mexico?

The decrease in the number of agricultural workers is a serious issue in Mexico. We hypothesized that migration might push the head of the household to exit from agriculture. The effect differs between farming and non-farming households because the former could increase farm income by devoting part of their remittance income to agricultural production. This study examines the relationship between the migration of household heads and their engagement in agriculture after returning home and their use of agricultural inputs. We found no significant relationship between migration and engagement in farming for farming households but a negative and significant relationship for non-farming households. In addition, we found a positive and significant relationship between migration and input use in farming households. This suggests that migration is likely to cause the exit of household heads from agriculture, but the possibility of increased farm income by purchasing more inputs may mitigate this effect.

The differences of the acromiohumeral interval between supine and upright radiographs of the shoulder

The acromiohumeral interval (AHI) is a measurement used to determine the superior migration of the humeral head in rotator cuff (RC) tear patients. The purpose of this study was to compare the AHI of; supine, upright shoulder radiographs, and magnetic resonance imaging (MRI) of the shoulder. The 86 shoulders were divided into 3 groups that included; (1) non-full thickness tear (50%), (2) full thickness (FT) tear ≤3 cm (33.7%), and (3) FT tear > 3 cm (16.3%). The mean difference of AHI noted was significantly lower in the supine radiographs and MRIs than with the upright (1.34–1.37 mm, 1.62–1.87 mm, respectively). Upright AHI ≤ 7.0 mm had 27.9% sensitivity and 100% specificity in diagnosing FT tears with 64% accuracy (p < 0.001). The supine AHI ≤ 6.5 mm had 32.6% sensitivity, 100.0% specificity, and 66.3% accuracy (p < 0.01). The results revealed the AHI in supine radiographs were significantly lower than upright shoulder radiographs. For AHI ≤ 7 mm in upright shoulder radiographs, this remains as an appropriate diagnostic test for ruling in shoulders with full thickness rotator cuff tears. This value was not relevant for use as the cut point in the supine radiographs and MRIs.

Expression of LATS1 in head and neck squamous cell carcinoma and its effect on tumor cell proliferation and invasion.

Nowadays, the incidence and mortality of head and neck tumors are gradually increasing. Head and neck malignant tumors (such as laryngeal cancer, hypopharyngeal cancer, oral cancer, nasopharyngeal cancer, oropharyngeal cancer, and other head and neck malignancies) are more common among systemic tumors. The most common pathological head and neck tumor type is squamous cell carcinoma, accounting for about 90%. In this study, immunohistochemical methods were used to collect the normal squamous epithelial tissues of the head and neck, atypical hyperplasia tissues, and head and neck squamous cell carcinomas on a tissue chip for detection. The recombinant LATS1 overexpression plasmid was prepared and transferred into B88 cells. Western blotting, MTT, and Transwell chamber methods were used to detect the effects of LATS1 proliferation, migration, and B88 cell overexpression. The experimental results showed that in head and neck squamous cell carcinoma, the expression of LATS1 protein decreased from 59.3% to 11.3%. At the same time, this protein inhibited the proliferation, migration, and invasion of head and neck squamous epithelial cells and also inhibited epithelium- Interstitial transformation exerts its tumor suppressor effect, indicating that LATS1 may play a tumor suppressor effect as a tumor suppressor gene. An in-depth study of the role and mechanism of LATS1 protein in the occurrence of head and neck squamous cell carcinoma may provide new opportunities for the treatment of head and neck squamous cell carcinoma in the future.

Receptor, Signal, Nucleus, Action: Signals That Pass through Akt on the Road to Head and Neck Cancer Cell Migration.

Simple SummaryThe ecosystem that surrounds a tumour, the microenvironment, has a huge impact on the spread of cancer, but its exact role in the molecular mechanism of spreading is still under scrutiny. This literature review aims to focus on the evidence published on the production of growth factors or proteins from the tumour microenvironment, which initiate signals in cancer cells. This review provides evidence that when Akt, a signalling protein, is activated by different growth factors such as epidermal growth factor, transforming growth factor α/β, vascular endothelial growth factor and nerve growth factor, head and neck cancer cell spreading is stimulated. In a nutshell, it demonstrates that the tumour microenvironment plays an important role in cancer spreading by synthesising and secreting growth factors and suggests that targeting growth-factor-activated Akt in combination therapy could be a valuable therapeutic approach in treating head and neck cancer patients.This review aims to provide evidence for the role of the tumour microenvironment in cancer progression, including invasion and metastasis. The tumour microenvironment is complex and consists of tumour cells and stromal-derived cells, in addition to a modified extracellular matrix. The cellular components synthesise growth factors such as EGF, TGFα and β, VEGF, and NGF, which have been shown to initiate paracrine signalling in head and neck cancer cells by binding to cell surface receptors. One example is the phosphorylation, and hence activation, of the signalling protein Akt, which can ultimately induce oral cancer cell migration in vitro. Blocking of Akt activation by an inhibitor, MK2206, leads to a significant decrease, in vitro, of cancer-derived cell migration, visualised in both wound healing and scatter assays. Signalling pathways have therefore been popular targets for the design of chemotherapeutic agents, but drug resistance has been observed and is related to direct tumour–tumour cell communication, the tumour–extracellular matrix interface, and tumour–stromal cell interactions. Translation of this knowledge to patient care is reliant upon a comprehensive understanding of the complex relationships present in the tumour microenvironment and could ultimately lead to the design of efficacious treatment regimens such as targeted therapy or novel therapeutic combinations.

Severe limitation of motion caused by a deformity and migration of the radial head after early surgical intervention for osteochondritis dissecans in a juvenile baseball player

Severe limitation of motion caused by a deformity and migration of the radial head after early surgical intervention for osteochondritis dissecans in a juvenile baseball player

Quantitative statistical shape model-based analysis of humeral head migration, Part 2: Shoulder osteoarthritis.

We wanted to investigate the quantitative characteristics of humeral head migration (HHM) in shoulder osteoarthritis (OA) and their possible associations with scapular morphology. We quantified CT-scan-based-HHM in 122 patients with a combination of automated 3D scapulohumeral migration (=HHM with respect to the scapula) and glenohumeral migration (=HHM with respect to the glenoid) measurements. We divided OA patients in Group 1 (without HHM), Group 2a (anterior HHM) and Group 2b (posterior HHM). We reconstructed and measured the prearthropathy scapular anatomy with a statistical shape model technique. HHM primarily occurs in the axial plane in shoulder OA. We found "not-perfect" correlation between subluxation distance AP and scapulohumeral migration values (rs = 0.8, p < 0.001). Group 2b patients had a more expressed prearthropathy glenoid retroversion (13° vs. 7°, p < 0.001) and posterior glenoid translation (4 mm vs. 6 mm, p = 0.003) in comparison to Group 1. Binary logistic regression analysis indicated prearthropathy glenoid version as a significant predictor of HHM (χ² = 27, p < 0.001). Multivariate regression analysis showed that the pathologic version could explain 56% of subluxation distance-AP variance and 75% of the scapulohumeral migration variance (all p < 0.001). Herewith, every degree increase in pathologic glenoid retroversion was associated with an increase of 1% subluxation distance-AP, and scapulohumeral migration. The occurrence of posterior HHM is associated with prearthropathy glenoid retroversion and more posterior glenoid translation. The reported regression values of HHM in the function of the pathologic glenoid version could form a basis towarda more patient-specific correction of HHM.

Risk Factors for Radiological Progression of Massive Rotator Cuff Tear

Hamada classification has shown that massive rotator cuff tears can progress to the superior migration of the humeral head and arthritic change of the glenohumeral joint can occur on plain radiography; however, the risk factors for its progression remain largely unknown. This study aimed to clarify the predictive factors that affect the radiological progression of massive rotator cuff tears.

The influence of tone on proximal femoral and acetabular geometry in neuromuscular hip displacement: A comparison of cerebral palsy and spinal muscular atrophy.

Purpose:The aim of this article was to compare longitudinal changes in hip morphology in cerebral palsy (hypertonic) and spinal muscular atrophy (hypotonic) to examine the influence of muscle tone on development of hip displacement.Methods:Children with spinal muscular atrophy (Types I and II) and cerebral palsy (Gross Motor Function Classification System IV and V) with hip displacement (migration percentage >30%) were included. Head shaft angle, migration percentage, and acetabular index were measured at T1 (1–2.5 years), T2 (3–5 years), and T3 (6–8 years). Analysis of variance testing and linear regression were utilized.Results:Sixty patients (cerebral palsy, N = 41; spinal muscular atrophy, N = 19) were included. Hip displacement occurred earlier in spinal muscular atrophy (34 months) than cerebral palsy (49 months) (p = 0.003). Head shaft angle was high and did not change between T1, T2, and T3, but significant changes in migration percentage were found (cerebral palsy: 23%, 36%, 45% (p < 0.01) and spinal muscular atrophy: 37%, 57%, 61% (p = 0.02)). Migration percentage increased by age in cerebral palsy (r = 0.41, p < 0.001), but not in spinal muscular atrophy (r = 0.18, p = 0.09). Acetabular index increased with migration percentage (cerebral palsy: r = 0.41, p < 0.001; spinal muscular atrophy: r = 0.48, p < 0.001).Conclusion:Persistent lateral physeal tilt by head shaft angle was found for both spinal muscular atrophy and cerebral palsy. Abnormal physeal alignment may be causally related to weakness of the hip abductor muscles rather than spasticity or muscle imbalance, resulting in coxa valga and secondary acetabular dysplasia.Level of evidence:III (case–control study).

Quantifying Rates of Landscape Unzipping

AbstractMeasuring rates of valley head migration and determining the timing of canyon‐opening are insightful for the evolution of planetary surfaces. Spatial gradients of in situ‐produced cosmogenic nuclide concentrations along horizontal transects provide a framework for assessing the migration of valley networks and similar topographic features. We developed a new derivation for valley head retreat rates from the concentrations of in situ‐produced cosmogenic radionuclides in valley walls. The retreat rate is inversely proportional to the magnitude of the spatial concentration gradient and proportional to local nuclide production rates. By solving for a spatial gradient in concentration along a valley parallel transect, we created an expression for the explicit determination of valley head retreat, which we refer to herein as unzipping. We applied this expression to a seepage‐derived drainage network developing along the Apalachicola River, Florida, USA. Sample concentrations along a valley margin transect varied systematically from 2.9 × 105 to 3.5 × 105 atoms/g resulting in a gradient of 160 atoms/g/m, and from this value a valley head retreat rate of 0.025 m/y was found. The discrepancy between overall network age and current rates of valley head migration suggests intermittent network growth which is consistent with glacial‐interglacial precipitation variations during the Pleistocene. This method can be applied to a wide range of Earth‐surface environments. For the 10Be system, this method should be sensitive to unzipping rates bounded between 10−6 and 100 m/y.

AAOS Appropriate Use Criteria: Management of Rotator Cuff Pathology.

AAOS Appropriate Use Criteria: Management of Rotator Cuff Pathology.

The Chaperone Protein GRP78 Promotes Survival and Migration of Head and Neck Cancer After Direct Radiation Exposure and Extracellular Vesicle-Transfer.

Background and PurposeIncreased levels of the chaperone protein GRP78 have been implicated in poorer outcomes of cancer therapy. We have therefore explored the functional connection between the expression of GRP78 and the development of radioresistance and metastatic behavior in HNSCC.Material and MethodsThe association between gene expression of GRP78 and survival in HNSCC patients was examined using the TCGA database. The influence of ionizing radiation on the GRP78 levels in HNSCC cell lines, their secreted extracellular vesicles (EV) and non-irradiated EV-recipient cells was investigated by Western Blot and FACS. The consequences of chemical inhibition or experimental overexpression of GRP78 on radioresistance and migration of HNSCC cells were analyzed by clonogenic survival and gap closure assays.ResultsElevated levels of GRP78 RNA in HNSCC correlated with poorer overall survival. Radiation increased GRP78 protein expression on the surface of HNSCC cell lines. Experimental overexpression of GRP78 increased both radioresistance and migratory potential. Chemical inhibition of GRP78 impaired cell migration. EVs were identified as a potential source of increased GRP78 content as elevated levels of surface GRP78 were found in EVs released by irradiated cells. These vesicles transferred GRP78 to non-irradiated recipient cells during co-cultivation.ConclusionsWe have identified the chaperone protein GRP78 as a potential driver of increased radioresistance and motility in HNSCC. The uptake of GRP78-rich EVs originating from irradiated cells may contribute to a poorer prognosis through bystander effects mediated by the transfer of GRP78 to non-irradiated cells. Therefore, we consider the chaperone protein GRP78 to be an attractive target for improving radiotherapy strategies.

Hip Pain in Patients With Spinal Muscular Atrophy: Prevalence, Intensity, Interference, and Factors Associated With Moderate to Severe Pain.

A subset of patients with spinal muscular atrophy (SMA) develop hip pain. We analyzed (1) the characteristics of hip pain in patients with SMA (prevalence, intensity, interference with activities, and responsiveness to treatment) and (2) factors (patient, clinical, and radiographic) associated with moderate to severe pain. We performed a retrospective record review and telephone survey of 104 patients with SMA (77% response rate; 44% female; mean age, 22±13 y) who presented for treatment between 2010 and 2020. Patient, clinical, and radiographic characteristics (when available) were recorded. Patients with current or past hip pain were asked about pain characteristics. Pain intensity and interference were assessed with the Brief Pain Inventory, modified for SMA (scale, 0 to 10 with 0 indicating no pain/interference). We used univariate analysis and ordered logistic regression to determine associations between patient factors and hip pain (α=0.05). Hip pain occurred in 60/104 patients (58%), with 15 (14%) indicating moderate to severe pain. Compared with patients with normal body mass index values, patients who were obese had 5.4 times the odds [95% confidence interval (CI), 1.3-23] of moderate to severe pain. Hip contractures [adjusted odds ratio (aOR), 3.2; 95% CI, 1.2-8.8] and dislocations (aOR, 2.9; 95% CI, 1.1-7.9) were associated with greater odds of pain compared with hips without these presentations. Surgical correction for scoliosis (aOR, 2.6; 95% CI, 1.1-6.5) was also associated with greater odds of moderate to severe pain. Femoral head migration percentage was the only radiographic parameter associated with pain. Mean modified Brief Pain Inventory pain intensity was 2.1±2.3. Prolonged sitting, sleep, and transfers (eg, bed to wheelchair) were the activities most affected by pain. Hip pain was moderate to severe in 14% of patients with SMA. Obesity, hip contractures, surgical correction of scoliosis, and hip dislocations were independently associated with pain. Although mean pain intensity was low, hip pain interfered with daily activities, including prolonged sitting, sleep, and transfers. Level III.

Latissimus dorsi transfer with amodified single-incision Herzberg technique and description of its arthroscopic advancement

Latissimus dorsi transfer aims to reduce pain and improve function for irreparable tears of the posterosuperior rotator cuff by restoring the transversal force couple to improve external rotation and delaying superior migration of the humeral head. Surgery is advocated in patients with unbearable shoulder pain and limited external rotation caused by an irreparable posterosuperior rotator cuff tear. Usually, alatissimus transfer is recommended in the presence of superior migration of the humeral head, higher grade fatty infiltration of the rotator cuff and arestriction of range of motion and strength for abduction and external rotation. Advantages of the arthroscopically assisted technique are the missing need of detaching the deltoid from its origin, smaller incisions and therapy of concomitant intraarticular lesions. Little pain and sufficient shoulder function in massive posterosuperior rotator cuff tears do not necessitate latissimus transfer. In the presence of subscapularis tears, osteoarthritis and deltoid dysfunction as well as shoulder stiffness tendon transfer are associated with inferior clinical outcomes. Surgery is performed in prone position. The incision is made about 5 cm caudal of the posterolateral corner of the acromion and extends over 6 cm at the inferior border of the deltoid muscle. After exploration and protection of the axillary and radial nerve the latissimus tendon is peeled off of the humerus. The medial part of the latissimus is then mobilized to gain length for the later transfer. Afterwards the footprint of the infraspinatus is visualized and debrided. Two or three suture anchors are placed into the posterosuperior aspect of the greater tuberosity. The sutures are stitched through the tendon in ahorizontal mattress stitch configuration and the tendon tied onto the bone. In arthroscopic advancement, the patient is placed in an upright beach-chair position with the arm attached to an arm holder. After debridement of the supraspinatus and infraspinatus footprint, arthroscopic preparation at the anterior border of the subscapularis tendon is performed. The latissimus tendon is visualized and detached with electrocautery. Afterwards the interval between posterior rotator cuff and deltoid muscle is prepared to allow the transfer of the latissimus tendon to the posterosuperior footprint. This marks the transition to the open approach, in which the arm is placed in aflexed and internally rotated position. Immobilization in ashoulder sling for 3weeks. Early passive range of motion (ROM: flexion30°, internal rotation60°, abduction0°, external rotation0°) was immediately allowed. After 3weeks, passive ROM was increased to90° of flexion, 60° of abduction, whereas external rotation was still restricted. After 7weeks, free passive ROM and after 8weeks active ROM (assisted) were allowed. In all, 67patients (mean age 63years) were examined 54months (± 28) after open transfer of the latissimus dorsi tendon. Constant score improved from 24 (± 6) points to 68 (± 17) points. Active flexion increased from 83° (± 47°) to 144° (± 35°), abduction from 69° (± 33°) to 134° (± 42°) and external rotation from 24° (± 18°) to 35° (± 21°). The VAS score decreased from 6.3 (± 1.1) to 1.8 (± 2). However, osteoarthritis worsened over time and the Hamada-Fukuda stage increased from1.4 to2.1 and the acromihumeral distance decreased from 7.9 (± 2.6) to 5.1 (± 2.2) at final follow-up.

Targeting CCL2-CCR4 axis suppress cell migration of head and neck squamous cell carcinoma

For head and neck squamous cell carcinoma (HNSCC), the local invasion and distant metastasis represent the predominant causes of mortality. Targeted inhibition of chemokines and their receptors is an ongoing antitumor strategy established on the crucial roles of chemokines in cancer invasion and metastasis. Herein, we showed that C-C motif chemokine ligand 2 (CCL2)- C-C motif chemokine receptor 4 (CCR4) signaling, but not the CCL2- C-C motif chemokine receptor 2 (CCR2) axis, induces the formation of the vav guanine nucleotide exchange factor 2 (Vav2)- Rac family small GTPase 1 (Rac1) complex to activate the phosphorylation of myosin light chain (MLC), which is involved in the regulation of cell motility and cancer metastasis. We identified that targeting CCR4 could effectively interrupt the activation of HNSCC invasion and metastasis induced by CCL2 without the promoting cancer relapse observed during the subsequent withdrawal period. All current findings suggested that CCL2-CCR4-Vav2-Rac1-p-MLC signaling plays an essential role in cell migration and cancer metastasis of HNSCC, and CCR4 may serve as a new potential molecular target for HNSCC therapy.

Irradiated fibroblasts increase interleukin-6 expression and induce migration of head and neck squamous cell carcinoma.

BackgroundCytotoxic effects of radiation play an important role in the treatment of head and neck cancer. However, irradiation is known to lead to the migration of various cancer cells, including those of head and neck cancer. Recently, fibroblasts in the cancer microenvironment have been reported to be involved in this mechanism. Nevertheless, the mechanism underlying migration of head and neck cancer cells remains unclear. Herein, we aimed to elucidate this migration mechanism induced by irradiation in terms of the interaction of head and neck cancer cells with fibroblasts.MethodsWe used the head and neck squamous cell carcinoma (HNSCC) cell lines SAS and FaDu as well as fibroblast cell lines. These cells were irradiated and their viability was compared. In fibroblasts, changes in interleukin-6 (IL-6) secretion caused by irradiation were measured by enzyme-linked immunosorbent assay (ELISA). The cell migration ability of cancer cells was evaluated via a migration assay using a semipermeable membrane. HNSCC cells were cocultured with irradiated and nonirradiated fibroblasts, and their migration ability under each condition was compared. We also examined the effect of IL-6 on the migration of HNSCC cells. Furthermore, to investigate the effect of fibroblast-derived IL-6 on the migration ability of HNSCC cells, we conducted a coculture study using IL-6 neutralizing antibody.ResultsIrradiation reduced the survival of HNSCC cells, whereas fibroblasts were resistant to irradiation. Irradiation also increased IL-6 secretion by fibroblasts. Migration of HNSCC cells was enhanced by coculture with fibroblasts and further enhanced by coculture with irradiated fibroblasts. We also confirmed that the migration of HNSCC cells was induced by IL-6. The enhanced migration of cancer cells caused by coculturing with fibroblasts was canceled by the IL-6 neutralizing antibody.ConclusionThese results show that fibroblasts survive irradiation and induce the migration ability of HNSCC cells through increased secretion of IL-6.

A Brief Review of Reverse Shoulder Arthroplasty for Rotator Cuff Arthropathy

Reverse total shoulder arthroplasty is an increasingly popular procedure performed by orthopedic surgeons. The indications have expanded over the past two decades with well documented success in the treatment of rotator cuff arthropathy. Patients with loss of rotator cuff function experience altered shoulder biomechanics that lead to superior humeral head migration, acetabulization of the acromion and progressive glenohumeral arthritis. Clinically, patients present with chronic shoulder pain, weakness and loss of range of motion that impacts activities of daily living. To address this, a reverse total shoulder can be performed. The procedure is normally done in the beach chair position utilizing the deltopectoral approach. A humeral stem with liner and glenosphere is implanted into the humerus and scapula, respectively. The procedure has shown consistent improvements in pain, strength, range-of-motion and function. Complications include dislocation, instability, fracture and infection.