A mechanobiological model of bone metastasis reveals that mechanical stimulation inhibits the pro-osteolytic effects of breast cancer cells.

Bone is highly susceptible to cancer metastasis, and both tumor and bone cells enable tumor invasion through a "vicious cycle" of biochemical signaling. Tumor metastasis into bone also alters biophysical cues to both tumor and bone cells, which are highly sensitive to their mechanical environment. However, the mechanobiological feedback between these cells that perpetuate this cycle has not been studied. Here, we develop highly advanced in vitro and computational models to provide an advanced understanding of how tumor growth is regulated by the synergistic influence of tumor-bone cell signaling and mechanobiological cues. In particular, we develop a multicellular healthy and metastatic bone model that can account for physiological mechanical signals within a custom bioreactor. These models successfully recapitulated mineralization, mechanobiological responses, osteolysis, and metastatic activity. Ultimately, we demonstrate that mechanical stimulus provided protective effects against tumor-induced osteolysis, confirming the importance of mechanobiological factors in bone metastasis development.

Grade of Primary Cutaneous Leiomyosarcoma Dictates Risk for Metastatic Spread and Disease-Specific Mortality.

BACKGROUND AND OBJECTIVES: Primary cutaneous leiomyosarcoma (cLMS), a rare, typically intradermal tumor, has previously been reported to exhibit an indolent course of disease with zero-to-low risk of local recurrence or distant metastasis. This study seeks to evaluate recurrence and survival of cLMS patients through study of its clinicopathologic and treatment characteristics. METHODS: All patients included underwent resection of primary cLMS at this institution between 2006 and 2019. A retrospective cohort study analysis of clinicopathologic characteristics, treatment, recurrence, and overall survival was performed. Data was assessed through descriptive statistics and outcome measures assessed by Cox proportional models and log-rank tests. RESULTS: Eighty-eight patients with cLMS were evaluated. The majority were men (n = 68, 77%) and Caucasian (n = 85, 97%), with median age at diagnosis of 66 years (range 20-96). 65% of tumors were located on the extremities, with a median size of 1.3 cm (range .3-15). Assessment revealed low (n = 41, 47%), intermediate (n = 29, 33%), and high (n = 18, 20%) grade tumors, demonstrating extension into subcutaneous tissue in 38/60 (60%), with 3 patients exhibiting extension into muscle (3%). All underwent resection as primary treatment with median 1 cm margins (range .5-2). With median follow-up of 27.5 months (IQR 8-51; range 1-131), no low-grade cases had recurrence or death while there was a recurrence rate of 19.1% (9/47) and death rate of 8.5% (4/47) in intermediate- to high-grade cases. CONCLUSIONS: Primary tumor resection of cLMS provides excellent local control for low-grade tumors as no low-grade cases experienced recurrence. For patients with intermediate- to high-grade tumors, there is potential for local recurrence, distant metastasis, and death, and therefore surveillance following treatment is encouraged.

The impact of socioeconomic status on survival in stage III colon cancer patients: A retrospective cohort study using the SEER census-tract dataset.

BACKGROUND: The impact of socioeconomic status (SES) has been described for screening and accessing treatment for colon cancer. However, little is known about the "downstream" effect in patients who receive guideline-concordant treatment. This study assessed the impact of SES on cancer-specific survival (CSS) and overall survival (OS) for stage III colon cancer patients. METHODS: The SEER Census Tract-Level SES Dataset from 2004 to 2015 was used to identify stage III colon adenocarcinoma patients who received curative-intent surgery and adjuvant chemotherapy. The predictor variable was census tract SES. SES was analyzed as quintiles. The outcome variables were OR and CSS. Statistical analysis included chi square tests for association, Kaplan-Meier, Cox, Fine and Gray regression for survival analysis. RESULTS: In total, 27,222 patients met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid/uninsured, higher T stage, and lower grade tumors. CSS at the 25th percentile was 54 months for the lowest SES quintile and 80 for the highest. Median OS was 113 months for the lowest SES quintile and not reached for highest. The 5-year CSS rate was 72.4% for the lowest SES quintile compared to 78.9% in the highest (p < 0.001). The 5-year OS rate was 66.5% for the lowest SES quintile and 74.6% in the highest (p < 0.001). CONCLUSION: This is the first study to evaluate CSS and OS in an incidence-based cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline-based treatment, SES was associated with disparities in CSS and OS.

Resection Margins in Merkel Cell Carcinoma: Is a 1-cm Margin Wide Enough?

BACKGROUND: Guidelines regarding specific resection margins for primary Merkel cell carcinoma (MCC) are not well established. The current National Comprehensive Cancer Network (NCCN) guidelines recommend 1- to 2-cm resection margins. This study aimed to determine the impact of margin width on local recurrence (LR), disease-specific survival (DSS), overall survival (OS), and type of wound closure. METHODS: All patients who underwent resection of primary MCC at a single institution from 2000 to 2015 were reviewed. Patient demographics, clinicopathologic characteristics, treatments, and outcomes were reviewed. RESULTS: A total of 240 patients underwent resection of primary MCC with resection margin width identified in the operative report. The median age was 76 years, and 65.8% of the patients were men. Of the 240 patients, 85 (35.4%) had head and neck primaries, 140 (58.3%) had extremity primaries, and 15 (6.3%) had trunk primaries. In terms of margins, 69 patients (28.8%) had a margin of 1 cm, 36 patients (15%) had a margin of 1.1-1.9 cm, and 135 patients (56.2%) had a margin of 2 cm or more. The median follow-up period was 21 months. The LR rate was 2.9% for a margin of 1 cm, 2.8% for a margin of 1.1-1.9 cm, and 5.2% for a margin of 2 cm or more (p = 0.80). The 5-year OS was 63.6% for a margin of 1 cm, 59.7% for a margin of 1.1-1.9, and 70.7% for a margin of 2 cm or more (p = 0.66). The 5-year DSS was 80.3% for a margin of 1 cm, 66.2% for a margin of 1.1-1.9 cm, and 91.8% for a margin of 2 cm or more (p = 0.28). For wound closure, 43.5, 50, and 65.9% of the patients respectively required a flap or graft with a margin of 1, 1.1-1.9, and 2 cm or more (p = 0.006). CONCLUSIONS: A 1-cm resection margins did not increase the risk of LR. Margin width did not make a significant difference in DSS or OS. Larger resection margins increase the need for a graft or flap closure.

Female genitourinary tract melanoma: mutation analysis with clinicopathologic correlation: a single-institution experience.

Female genitourinary tract melanoma (FGTM) is a rare and often-fatal form of mucosal melanoma. We describe our institutional experience with 55 cases of FGTM, 16 of which were evaluated with next-generation sequencing targeting 151 cancer-associated genes. Tumors tended to be thicker than conventional melanoma at presentation (median: 3.2 mm), were frequently ulcerated (50%), and characterized by incomplete initial resections. Regional lymph nodes showed tumor involvement at presentation in 28% of cases. With a median follow-up of 23.6 months, the median recurrence free survival was 14.5 months and the median overall survival was 29.6 months. Genomic analysis revealed mutually exclusive mutations in TP53 and KIT in 25%, while 19% of cases showed BRAF mutation. NRAS mutation was found in 13% of cases. Mutation in ATRX, previously undescribed in mucosal melanoma, was seen in three (10%) of 16 patients. Only invasive melanoma cases were included in statistical analyses. Patients with three or more mutations had marginally worse overall survival rates than those with two or less (P=0.07). Further studies are required for potential adjuvant treatment modalities to improve survival outcomes of FGTM.

Investigating multi-radiomic models for enhancing prediction power of cervical cancer treatment outcomes.

Quantitative image features, also known as radiomic features, have shown potential for predicting treatment outcomes in several body sites. We quantitatively analyzed 18Fluorine-fluorodeoxyglucose (18F-FDG) Positron Emission Tomography (PET) uptake heterogeneity in the Metabolic Tumor Volume (MTV) of eighty cervical cancer patients to investigate the predictive performance of radiomic features for two treatment outcomes: the development of distant metastases (DM) and loco-regional recurrent disease (LRR). We aimed to fit the highest predictive features in multiple logistic regression models (MLRs). To generate such models, we applied backward feature selection method as part of Leave-One-Out Cross Validation (LOOCV) within a training set consisting of 70% of the original patient cohort. The trained MLRs were tested on an independent set consisted of 30% of the original cohort. We evaluated the performance of the final models using the Area under the Receiver Operator Characteristic Curve (AUC). Accordingly, six models demonstrated superior predictive performance for both outcomes (four for DM and two for LRR) when compared to both univariate-radiomic feature models and Standard Uptake Value (SUV) measurements. This demonstrated approach suggests that the ability of the pre-radiochemotherapy PET radiomics to stratify patient risk for DM and LRR could potentially guide management decisions such as adjuvant systemic therapy or radiation dose escalation.

Priming and cryopreservation of microencapsulated marrow stromal cells as a strategy for intervertebral disc regeneration.

A challenge in using stromal cells for intervertebral disc (IVD) regeneration is their limited differentiation capacity in vivo without exogenous growth factor (GF) supplementation. Priming of stromal cells prior to transplantation may offer a feasible strategy to overcome this limitation. Furthermore, the ability to cryopreserve cells could help alleviate logistical issues associated with storage and transport. With these critical translational challenges in mind, we aimed to develop a strategy involving priming and subsequent cryopreservation of microencapsulated bone marrow stromal cells (BMSCs). In phase one, we utilised the electrohydrodynamic atomisation process to fabricate BMSC-encapsulated microcapsules that were primed with TGF-ß3 for 14 d after which they were cultured for a further 21 d under basal or GF supplemented media conditions. Results showed that priming induced differentiation of BMSC microcapsules such that they synthesised significant amounts of sGAG (61.9 ± 2.0 µg and 55.3 ± 6.1 µg for low and high cell densities) and collagen (24.4 ± 1.9 µg and 55.3 ± 4.6 µg for low and high cell densities) in continued culture without GF supplementation compared to Unprimed microcapsules. Phase two of this work assessed the extracellular matrix forming capacity of Primed BMSC microcapsules over 21 d after cryopreservation. Notably, primed and cryopreserved BMSCs successfully retained the ability to synthesise both sGAG (24.8 ± 2.7 µg and 75.1 ± 11.6 µg for low and high cell densities) and collagen (26.4 ± 7.8 µg and 93.1 ± 10.2 µg for low and high cell densities) post-cryopreservation. These findings demonstrate the significant potential of priming and cryopreservation approaches for IVD repair and could possibly open new horizons for pre-designed, 'off-the-shelf' injectable therapeutics.

Recurrence patterns and associated factors of locoregional failure following neoadjuvant chemoradiation and surgery for esophageal cancer.

BACKGROUND: Despite neoadjuvant chemoradiation (nCRT) followed by esophagectomy for locally advanced esophageal cancer, locoregional recurrence (LRR) is common and factors associated with LRR have not been clearly identified. METHODS: Patients were identified from a single institution, prospectively maintained database (1996-2013). Patterns of recurrence were described and associated factors of LRR were analyzed using competing risks regression models. RESULTS: Of the 456 patients treated with nCRT and surgery, 167 patients developed recurrence. Locoregional and distant recurrences were observed in 69 (15.1%) and 140 (30.9%) patients, respectively. Time to recurrence (13.6 vs 10.4 months, P = 0.20) and median overall survival (29.3 vs 19.1 months, P = 0.12) were no different among the 27 patients (6%) who developed a solitary LRR compared to patients who developed distant recurrence. Univariable analysis identified lymphovascular invasion (HR 1.46, P = 0.07), lymph node ratio >0.5 (HR 2.16, P = 0.02), positive margin (HR 1.95, P = 0.05), lack of response to neoadjuvant therapy (HR 1.99, P < 0.01), clinical T stage (HR 2.62, P < 0.01) and final T3/4 stage (HR 2.06, P < 0.01) as factors significantly associated with LRR. Clinical T stage and response to neoadjuvant treatment were independently associated with LRR on multivariable analysis. CONCLUSIONS: Although aggressive tumor biology plays a significant role in LRR, optimizing neoadjuvant treatments to obtain a complete pathologic response may lead to improved locoregional control.

Bone Marrow Stem Cells in Response to Intervertebral Disc-Like Matrix Acidity and Oxygen Concentration: Implications for Cell-based Regenerative Therapy.

STUDY DESIGN: In vitro culture of porcine bone marrow stem cells (BMSCs) in varying pH microenvironments in a three-dimensional hydrogel system. OBJECTIVE: To characterize the response of BMSCs to varying pH environments (blood [pH 7.4], healthy intervertebral disc (IVD) (pH 7.1), mildly degenerated IVD (pH 6.8), and severely degenerated IVD (pH 6.5) in three-dimensional culture under normoxic (20%) and hypoxic (5%) conditions. SUMMARY OF BACKGROUND DATA: The IVD is an avascular organ relying on diffusion of essential nutrients through the cartilaginous endplates (CEPs) thereby creating a challenging microenvironment. Within a degenerated IVD, oxygen and glucose concentrations decrease further (<5% oxygen, <5 mmol/L glucose) and matrix acidity (

Living Cell Factories - Electrosprayed Microcapsules and Microcarriers for Minimally Invasive Delivery.

Minimally invasive delivery of "living cell factories" consisting of cells and therapeutic agents has gained wide attention for next generation biomaterial device systems for multiple applications including musculoskeletal tissue regeneration, diabetes and cancer. Cellular-based microcapsules and microcarrier systems offer several attractive features for this particular purpose. One such technology capable of generating these types of systems is electrohydrodynamic (EHD) spraying. Depending on various parameters, including applied voltage, biomaterial properties (viscosity, conductivity) and needle geometry, complex structures and arrangements can be fabricated for therapeutic strategies. The advances in the use of EHD technology are outlined, specifically in the manipulation of bioactive and dynamic material systems to control size, composition and configuration in the development of minimally invasive micro-scaled biopolymeric systems. The exciting therapeutic applications of this technology, future perspectives and associated challenges are also presented.

Extracellular matrix production by nucleus pulposus and bone marrow stem cells in response to altered oxygen and glucose microenvironments.

Bone marrow (BM) stem cells may be an ideal source of cells for intervertebral disc (IVD) regeneration. However, the harsh biochemical microenvironment of the IVD may significantly influence the biological and metabolic vitality of injected stem cells and impair their repair potential. This study investigated the viability and production of key matrix proteins by nucleus pulposus (NP) and BM stem cells cultured in the typical biochemical microenvironment of the IVD consisting of altered oxygen and glucose concentrations. Culture-expanded NP cells and BM stem cells were encapsulated in 1.5% alginate and ionically crosslinked to form cylindrical hydrogel constructs. Hydrogel constructs were maintained under different glucose concentrations (1, 5 and 25 mM) and external oxygen concentrations (5 and 20%). Cell viability was measured using the Live/Dead® assay and the production of sulphated glycosaminoglycans (sGAG), and collagen was quantified biochemically and histologically. For BM stem cells, IVD-like micro-environmental conditions (5 mM glucose and 5% oxygen) increased the accumulation of sGAG and collagen. In contrast, low glucose conditions (1 mM glucose) combined with 5% external oxygen concentration promoted cell death, inhibiting proliferation and the accumulation of sGAG and collagen. NP-encapsulated alginate constructs were relatively insensitive to oxygen concentration or glucose condition in that they accumulated similar amounts of sGAG under all conditions. Under IVD-like microenvironmental conditions, NP cells were found to have a lower glucose consumption rate compared with BM cells and may in fact be more suitable to adapt and sustain the harsh microenvironmental conditions. Considering the highly specialised microenvironment of the central NP, these results indicate that IVD-like concentrations of low glucose and low oxygen are critical and influential for the survival and biological behaviour of stem cells. Such findings may promote and accelerate the translational research of stem cells for the treatment of IVD degeneration.