Radiation therapy for retroperitoneal sarcoma: practice patterns in North America

BACKGROUND

The addition of radiation therapy (RT) to surgery in retroperitoneal sarcoma (RPS) remains controversial. We examined practice patterns in the use of RT for patients with RPS over time in a large, national cohort.

METHODS

Patients in the National Cancer Database (2004-2017) who underwent resection of RPS were included. Trends over time for proportions were calculated using contingency tables with Cochran-Armitage Trend test.

RESULTS

Of 7,485 patients who underwent resection, 1,821 (24.3%) received RT (adjuvant: 59.9%, neoadjuvant: 40.1%). The use of RT decreased annually by < 1% (p = 0.0178). There was an average annual increase of neoadjuvant RT by 13% compared to an average annual decrease of adjuvant RT by 6% (p < 0.0001). Treatment at high-volume centers (OR 14.795, p < 0.0001) and tumor > 10 cm (OR 2.009, p = 0.001) were associated with neoadjuvant RT. In contrast liposarcomas (OR 0.574, p = 0.001) were associated with adjuvant RT. There was no statistically significant difference in overall survival between patients treated with surgery alone versus surgery and RT (p = 0.07).

CONCLUSION

In the United States, the use of RT for RPS has decreased over time, with a shift towards neoadjuvant RT. However, a large percentage of patients are still receiving adjuvant RT and this mostly occurs at low-volume hospitals.

Preoperative radiation therapy increases adherence in patients with high-risk extremity soft tissue sarcoma

BACKGROUND

Surgery and radiation therapy remain the standard of care for patients with high-grade extremity soft tissue sarcoma that are >5 cm. Radiation therapy is time and labor-intensive for patients, and social determinants of health may affect adherence. The aim of this study was to define demographic, clinical, and treatment factors associated with the completion of radiation therapy and determine if preoperative radiation therapy improved adherence compared to postoperative radiation therapy.

METHODS

The cohort included patients in the National Cancer Database with high-grade extremity soft tissue sarcoma >5 cm without nodal or distant metastases who received limb-sparing surgery and radiation therapy with microscopically negative R0 margins. Multivariable logistic regression analyses identified factors associated with radiation therapy sequencing and adherence (defined as completion of 50 Gy preoperative radiation therapy or at least 60 Gy postoperative radiation therapy). A multivariable Cox Proportional Hazards model assessed overall survival.

RESULTS

Among 2,145 patients, 47.1% received preoperative radiation therapy (n = 1,010), and 52.9% (n = 1135) received postoperative radiation therapy. A greater proportion of patients treated with preoperative (77.2%) versus postoperative radiation therapy (64.9%, P < .0001) received the recommended dose. More patients with private insurance (49.8% vs 35.3% Medicaid vs 44.9% Medicare, P = .011) and patients treated at an academic medical center (52.6% vs 47.4%, P < .001) received preoperative radiation therapy. Patients who received preoperative radiation therapy had lower odds of receiving insufficient doses of radiation therapy (odds ratio 0.34 [95% CI 0.27-0.47]). Neither radiation therapy adherence nor sequencing were independent predictors of overall survival.

CONCLUSIONS

Patients who received preoperative radiation therapy were more likely to complete therapy and receive an optimal dose than patients treated with postoperative radiation therapy. Preoperative radiation therapy improves adherence and should be widely considered in patients with high-grade extremity soft tissue sarcoma, particularly in patients at risk for not completing therapy.

Disparities in Survival and NCCN Guideline-Concordant Care in Patients With Extremity Soft Tissue Sarcoma

BACKGROUND

Based on the NCCN Guidelines for Soft Tissue Sarcoma (STS), treatment of extremity STS (ESTS) includes radiation therapy (RT) and surgical resection for tumors that are high-grade and >5 cm. ​​The aim of this study was to describe the association between neighborhood socioeconomic status (nSES), concordance with NCCN Guidelines recommendations, and outcomes in patients with ESTS.

METHODS

Patients with ESTS diagnosed from 2006 through 2018 were identified in SEER registries. The analytic cohort was restricted to patients with high-grade tumors >5 cm without nodal or distant metastases who received limb-sparing surgery. Patient demographics and tumor characteristics associated with receipt of RT were analyzed using adjusted regression analyses. Kaplan-Meier curves and adjusted accelerated failure time models were used to examine disparities in cancer-specific survival.

RESULTS

Of 2,249 patients, 29.0% (n=648) received neoadjuvant RT, 49.7% (n=1,111) received adjuvant or intraoperative RT, and 21.3% (n=476) did not receive RT. In adjusted analyses, lower nSES was associated with lower likelihood of receiving RT (odds ratio, 0.70 [95% CI, 0.57-0.87]; P<.001). Low nSES was associated with worse cancer-specific survival (hazard ratio, 1.19 [95% CI, 1.01-1.40]; P=.04). Race and ethnicity were not significant predictors of receipt of RT or cancer-specific survival in the fully adjusted models.

CONCLUSIONS

Patients from lower nSES areas were less likely to receive NCCN Guideline-recommended RT for their ESTS and had worse cancer-specific survival. Efforts to better define and resolve disparities in the treatment and survival of patients with ESTS are warranted.

NCCN Guidelines® Insights: Merkel Cell Carcinoma, Version 1.2024

The NCCN Guidelines for Merkel Cell Carcinoma (MCC) provide recommendations for diagnostic workup, clinical stage, and treatment options for patients. The panel meets annually to discuss updates to the guidelines based on comments from expert review from panel members, institutional review, as well as submissions from within NCCN and external organizations. These NCCN Guidelines Insights focus on the introduction of a new page for locally advanced disease in the setting of clinical node negative status, entitled "Clinical N0 Disease, Locally Advanced MCC." This new algorithm page addresses locally advanced disease, and the panel clarifies the meaning behind the term "nonsurgical" by further defining locally advanced disease. In addition, the guideline includes the management of in-transit disease and updates to the systemic therapy options.

Basal Cell Skin Cancer, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology

Basal cell carcinoma (BCC) is the most common form of skin cancer in the United States. Due to the high frequency, BCC occurrences are not typically recorded, and annual rates of incidence can only be estimated. Current estimated rates are 2 million Americans affected annually, and this continues to rise. Exposure to radiation, from either sunlight or previous medical therapy, is a key player in BCC development. BCC is not as aggressive as other skin cancers because it is less likely to metastasize. However, surgery and radiation are prevalent treatment options, therefore disfigurement and limitation of function are significant considerations. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) outline an updated risk stratification and treatment options available for BCC.

Association between surgical delay and outcomes among patients with invasive cutaneous melanoma

BACKGROUND

The relationship between surgical delay and outcomes for patients with cutaneous melanoma is understudied. The objectives of this study were to determine the impact of surgical delay on regional nodal involvement and mortality in patients with cutaneous melanoma.

METHODS

Retrospective study of patients diagnosed with clinically node-negative invasive cutaneous melanoma from 2004 to 2018. Outcomes included regional lymph node disease and overall survival. Multivariable logistic regression and Cox proportional-hazards models were constructed to adjust for pertinent clinical factors.

RESULTS

Of 423,001 patients, 21.8% experienced a surgical delay (≥45 days). These patients were more likely to have nodal involvement (OR1.09; P ​= ​0.01). Surgical delay (HR1.14; P ​< ​0.001), Black race (HR1.34; P ​= ​0.002), and Medicaid (HR1.92; P ​< ​0.001) were associated with lower survival. Patients treated at academic/research (HR0.87; P ​< ​0.001) or integrated network cancer programs (HR0.89; P ​= ​0.001) had improve survival.

CONCLUSIONS

Surgical delay was frequent and resulted in higher rates of lymph node involvement and decreased overall survival.

Pleomorphic Dermal Sarcoma With Metastasis to the Lung: A Case Report

ABSTRACT

Atypical fibroxanthoma and pleomorphic dermal sarcoma (PDS) are dermal malignant mesenchymal tumors that lie at the ends of the same disease spectrum. Clinically indistinguishable from atypical fibroxanthoma, PDS has a more aggressive course with significantly higher rate of local recurrence and metastases. Histological findings that favor a PDS include subcutaneous invasion, tumor necrosis, lymphovascular invasion, and/or perineural infiltration. Herein, we report a case of PDS with metastasis to the lung. Our report highlights the risk of local recurrence and metastatic spread in this cutaneous tumor and the importance of distinguishing this entity from its less aggressive counterpart.

A rare tonsillar metastasis of Merkel cell carcinoma: A case report

Merkel cell carcinoma (MCC) metastasis to the tonsil is extremely rare with five published cases. We report the case of a patient with palatine tonsillar MCC metastasis, who presented without oropharyngeal symptoms, which contrast prior reported cases.

Prognostic factors in patients receiving surgery and radiation therapy for retroperitoneal sarcoma: A machine-learning analysis

BACKGROUND

The addition of radiation therapy to surgery for retroperitoneal sarcoma remains controversial. Improved patient selection may help identify optimal candidates for multimodality treatment. The aim of this analysis was to define prognostic factors among patients who receive radiation therapy and surgery to aid in patient selection for multimodal therapy.

METHODS

Patients who received radiation therapy and underwent curative-intent resection for retroperitoneal sarcoma between 2004 and 2016 were identified from a national cohort in the United States (National Cancer Database). A machine-based classification and regression tree model was used to generate similar groups of patients relative to overall survival based on preoperative factors.

RESULTS

A total of 1,443 patients received radiation therapy in addition to surgery. Median age was 61 years old and 55.0% were female. Most patients (66%) received care at an academic or integrated network cancer program. With a median follow-up of 84 months, receipt of radiation therapy was not associated with improved overall survival (P = .81). Classification and regression tree analysis revealed a significant association between overall survival and American Joint Committee on Cancer stage group, age, tumor histology, and Charlson comorbidity score. Application of these parameters via machine learning stratified patients into 5 cohorts with distinct survival outcomes. In the most favorable cohort (Cohort 1: American Joint Committee on Cancer stage group ≤II, age ≤61, histology including fibrosarcoma, well differentiated liposarcoma, myxoid liposarcoma, and leiomyosarcoma), the 5-year overall survival was 81.7% and median overall survival was not reached; in the least favorable cohort (Cohort 6: American Joint Committee on Cancer stage group >II, age >68) where the 5-year survival was 41.3% and median overall survival was 45.2 months (P < .001 versus Cohort 1).

CONCLUSION

In the absence of a defined survival benefit, patients with advanced American Joint Committee on Cancer stage group, older age, and medical comorbidities have relatively unfavorable overall survival after combined modality therapy and therefore stand the least to gain from the addition of radiation therapy to surgery. In contrast, younger patients with good performance status and retroperitoneal sarcoma histologies with a higher propensity for local recurrence may have the greatest opportunity to benefit from radiation therapy.

Morbidity and Mortality after Surgery for Retroperitoneal Sarcoma

Retroperitoneal sarcoma (RPS) is a rare disease with over 100 histologic types and accounts for 10-15% of all soft tissue sarcomas. Due to the rarity of RPS, sarcoma centers in Europe and North America have created the Transatlantic RPS Working Group (TARPSWG) to study this disease and establish best practices for its management. Current guidelines dictate complete resection of all macro and microscopic disease as the gold standard for patients with RPS. Complete extirpation often requires a multi-visceral resection. In addition, recent evidence suggests that en bloc compartmental resections are associated with reduced rates of local recurrence. However, this approach must be balanced by the potential for added morbidity. Strategies to mitigate postoperative complications include optimization of the patient through improved preoperative nutrition and pre-habilitation therapy, referral to a high-volume sarcoma center, and implementation of enhanced recovery protocols. This review will focus on the factors associated with perioperative complications following surgery for RPS and outline approaches to mitigate poor surgical outcomes in this patient population.

Evaluating efficacy on tumor biopsy tissue ex vivo before treatment for equitable cancer care

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Background: Nearly half the world will be diagnosed with cancer. Each year, > 1.7 million new cancers are diagnosed in the US. Worse, systemic therapy turns out to be ineffective in 70% of patients because those drugs do not match the patient’s tumor, imposing a substantial physical, emotional, and financial burden. Each tumor’s distinct composition and heterogeneity can result in diverse responses to the same treatment. There is a critical and urgent need to develop ex vivo personalized cancer models that match patients with the right treatment – before treatment. Here we present a low-cost ex vivo personalized cancer model to rapidly evaluate effectiveness of various therapeutics on intact core biopsy tissue obtained from a patient’s tumor. Objective: The goal of this study is to deliver multiple isolated fluid streams to spatially distinct regions (SDRs) of intact core biopsy specimens for evaluating efficacy of multiple anticancer agents simultaneously. Methods: Core biopsies were generated from xenograft and resected human tumor tissue using 18-gauge and 20-gauge spring-loaded biopsy systems. Xenografts were established using cell lines with known sensitivity and resistance profiles. Fluid streams with anticancer agents, nucleic acid stains, and mock drugs were delivered to spatially distinct regions (SDRs) on intact core biopsy specimens in our patented Personalized Oncology Efficacy Test (POET) lab-chip bioreactors. High content imaging and custom image processing algorithms were used to measure differential activity. Results: No lateral fluid surface conduction, and only minimal lateral diffusion, was observed up to 200 μm deep in tissue. Extent of observed lateral diffusion was within operational parameters of the bioreactor. Integrity of spatially distinct regions on intact core tissue was maintained. Differential activity from anticancer agents compared to mock drugs was observed and quantitatively measured using custom image processing algorithms. Conclusions: The NCI warns that “current methods to assess potential cancer treatments are cumbersome, expensive, and often inaccurate.” A personalized medicine approach, based on efficacy observed on tissue directly from the patient’s own tumor, is fundamentally better than the current approach. Low-cost next generation ex vivo cancer models that can rapidly match treatments to tumors, such as POET, could transform cancer treatment and make a significant impact on the lives of patients.

Preanalytical protocols for improving access to live tissue diagnostics in remote and low resource settings

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Background: Nearly 70% of diagnostics lab test errors occur due to variability in preanalytical factors. Preanalytical factors comprise parameters from the time tissue is extracted from the patient to the time it is tested in the lab. For lack of standardized preanalytical protocols, integrity of collected specimens is often compromised. This is particularly pronounced when specimens are collected in remote or low resource settings and shipped to testing facilities. Establishing preanalytical protocols could serve as an important resource for remote collection sites and substantially reduce variability in the integrity of specimens thereby improving lab test rigor and reproducibility and promote innovation in live tissue diagnostic tests for personalized medicine. Objective: The aim of this study is to analyze impact of cold chain logistics on integrity of collected solid tumor tissue specimens. Specifically, duration in transit, container and wet ice packing, and composition of transport media were assessed. Methods: Baseline protocols for biospecimen preanalytical parameters were established from literature review. Standard aseptic lab protocols were implemented for all experiments including preparation of transport media, tissue transport kits, transport kit packaging, tumor tissue transfer in tissue transport kits, tissue receiving, and tissue integrity assessment. Transport was simulated for human and murine pancreatic ductal adenocarcinoma (PDAC) tissue by holding packaged tumor tissue containers in storage for the duration of transport. Saline solution, basal media, and complete media were evaluated as transport media. Specimen integrity was evaluated using live/dead assays in high-content imaging systems at 24- and 48-hour intervals. Results: For human and murine tumor tissue, viability was optimal when tissue was transported in Nalgene jars containing complete media packaged in ¼” thick wall Styrofoam containers tightly packed in wet ice for transport. While specimens fared well over both 24- and 48- hour simulated shipping durations, temperature and humidity logs from sensors embedded in the packages showed sharp degradation in packaging environment with longer durations of time. Conclusions: Establishing preanalytical protocols would improve rigor and reproducibility in diagnostic lab tests by improving tissue viability and integrity. Such protocols would also enable next generation cancer models to further enhance predictive capacity in translational research and subsequently in personalized medicine applications at the bedside.

Democratizing cancer innovation by reducing cost and complexity of cancer models

e13503

Background: Despite advances in high-throughput screening, combinatorial chemistry, databanks, and computational models, drug R&D remains expensive and slow, often over a decade. It is estimated that pre-human costs are > 30% of cost of approved drugs: $1.5 billion of $3.9 billion. Another study estimates that pharma spends $34.4 billion annually on preclinical research. However, 90% of drugs effective in pre-human studies fail in human trials. A reason for this dissonance is the inadequacy of current assays and methods for evaluating efficacy of new treatments during preclinical evaluation. Cell culture dishes fail to recapitulate the in vivo microenvironment, making cells far from physiologically relevant. Animal models, though physiologically relevant, are limited indicators of success in subsequent human trials. Predicting which preclinical formulations will most likely succeed in clinical trials, by matching them against patient biopsy specimens, could reduce cost and time-to-market of new therapeutics. Objective: The aim of this study is to develop an ex vivo cancer model that can predict clinical success of preclinical formulations by screening efficacy on live patient biopsy tissue. Methods: Softlithography with SU-8 photoresist and polydimethylsiloxane (PDMS) was used to fabricate microporous thin membranes with uniform porosity. Electrospinning with collagen and Nylon was used for fabricating nanofibrous membranes with well-interconnected, non-woven, non-uniform porosity. Multicellular biomimetic healthy and tumorous microtissue was cultured with pancreatic and colorectal cell lines. Permeability assays were used to validate barrier and transport functions, scanning electron microscopy was used to validate morphology, and fluorescent and confocal microscopy were used to observe migration, invasion, and metastasis. Results: Permeability assay confirmed transport and barrier functions wherein small molecules (10 kDa) diffused while larger molecules (500 kDa) were prevented from flowing. Migration and invasion were observed when microfluidic circuits connected S2VP10-Luc “tumorous” tissue upstream from “healthy” vascular and muscle tissue. Moreover, subpopulations of invasive cells showed a more aggressive proliferation profile compared to subpopulations of the same cell-line cancer cells that remained at the original “tumorous” site. Conclusions: Microfluidic ex vivo cancer models have the potential to transform cancer treatment from bench – as clinical trial simulation tools to narrow down lead and backup candidates – to bedside – as predictive personalized companion diagnostics to guide treatment strategy – along the drug discovery to market roadmap for novel therapeutic agents.

Co-axial Projective Imaging for Augmented Reality Telementoring in Skin Cancer Surgery

Telemedicine has the potential to overcome the unequal distribution of medical resources worldwide. In this study, we report the second-generation co-axial projective imaging (CPI-2) system featured with orthotopic image projection for augmented reality surgical telementoring. The CPI-2 system can acquire surgical scene images from the local site, transmit them wirelessly to the remote site, and project the virtual annotations drawn by a remote expert with great accuracy to the surgical field. The performance characteristics of the CPI-2 system are quantitatively verified in benchtop experiments. The ex vivo study that compares the CPI-2 system and a monitor-based telementoring system shows that the CPI-2 system can reduce the focus shift and avoid subjective mapping of the instructions from a monitor to the real-world scene, thereby saving operation time and achieving precise teleguidance. The clinical feasibility of the CPI-2 system is validated in teleguided skin cancer surgery. Our ex vivo and in vivo experiment results imply the improved performance of surgical telementoring, and the clinical utility of deploying the CPI-2 system for surgical interventions in resource-limited settings. The CPI-2 system has the potential to reduce healthcare disparities in remote areas with limited resources.

NCCN Guidelines® Insights: Squamous Cell Skin Cancer, Version 1.2022

The NCCN Guidelines for Squamous Cell Skin Cancer provide recommendations for diagnostic workup, clinical stage, and treatment options for patients with cutaneous squamous cell carcinoma. The NCCN panel meets annually to discuss updates to the guidelines based on comments from panel members and the Institutional Review, as well as submissions from within NCCN and external organizations. These NCCN Guidelines Insights focus on the introduction of a new surgical recommendation terminology (peripheral and deep en face margin assessment), as well as recent updates on topical prophylaxis, immunotherapy for regional and metastatic disease, and radiation therapy.

Acral Lentiginous Melanoma: A United States Multi-Center Substage Survival Analysis

Background

Acral lentiginous melanoma is associated with worse survival than other subtypes of melanoma. Understanding prognostic factors for survival and recurrence can help better inform follow-up care.

Objectives

To analyze the clinicopathologic features, melanoma-specific survival, and recurrence-free survival by substage in a large, multi-institutional cohort of primary acral lentiginous melanoma patients.

Methods

Retrospective review of the United States Melanoma Consortium database, a multi-center prospectively collected database of acral lentiginous melanoma patients treated between January 2000 and December 2017.

Results

Of the 433 primary acral lentiginous melanoma patients identified (median [range] age: 66 [8–97] years; 53% female, 83% white), 66% presented with stage 0–2 disease and the median time of follow-up for the 392 patients included in the survival analysis was 32.5 months (range: 0–259). The 5-year melanoma-specific survivals by stage were 0 = 100%, I = 93.8%, II = 76.2%, III = 63.4%, IIIA = 80.8%, and IV = 0%. Thicker Breslow depth ((HR) = 1.13; 95% CI = 1.05–1.21; P < .001)) and positive nodal status ((HR) = 1.79; 95% CI = 1.00–3.22; P = .050)) were independent prognostic factors for melanoma-specific survival. Breslow depth ((HR = 1.13; 95% CI = 1.07–1.20; P < .001), and positive nodal status (HR = 2.12; 95% CI = 1.38–3.80; P = .001) were also prognostic factors for recurrence-free survival.

Conclusion

In this cohort of patients, acral lentiginous melanoma was associated with poor outcomes even in early stage disease, consistent with prior reports. Stage IIB and IIC disease were associated with particularly low melanoma-specific and recurrence-free survival. This suggests that studies investigating adjuvant therapies in stage II patients may be especially valuable in acral lentiginous melanoma patients.

The Devil's in the Details: Discrepancy Between Biopsy Thickness and Final Pathology in Acral Melanoma

PURPOSE

We hypothesized that initial biopsy may understage acral lentiginous melanoma (ALM) and lead to undertreatment or incomplete staging. Understanding this possibility can potentially aid surgical planning and improve primary tumor staging.

METHODS

A retrospective review of primary ALMs treated from 2000 to 2017 in the US Melanoma Consortium database was performed. We reviewed pathology characteristics of initial biopsy, final excision specimens, surgical margins, and sentinel lymph node biopsy (SLNB).

RESULTS

We identified 418 primary ALMs (321 plantar, 34 palmar, 63 subungual) with initial biopsy and final pathology results. Median final thickness was 1.8 mm (range 0.0-19.0). There was a discrepancy between initial biopsy and final pathology thickness in 180 (43%) patients with a median difference of 1.6 mm (range 0.1-16.4). Final T category was increased in 132 patients (32%), including 47% of initially in situ, 32% of T1, 39% of T2, and 28% of T3 lesions. T category was more likely to be increased in subungual (46%) and palmar (38%) melanomas than plantar (28%, p = 0.01). Among patients upstaged to T2 or higher, 71% had ≤ 1-cm margins taken. Among the 27 patients upstaged to T1b or higher, 8 (30%) did not have a SLNB performed, resulting in incomplete initial staging.

CONCLUSIONS

In this large series of ALMs, final T category was frequently increased on final pathology. A high index of suspicion is necessary for lesions initially in situ or T1 and consideration should be given to performing additional punch biopsies, wider margin excisions, and/or SLNB.

Telemedicine: Patient-Provider Clinical Engagement During the COVID-19 Pandemic and Beyond

BACKGROUND

The novel coronavirus pandemic has drastically affected healthcare organizations across the globe.

METHODS

We sought to summarize the current telemedicine environment in order to highlight the important changes triggered by the novel coronavirus pandemic, as well as highlight how the current crisis may inform the future of telemedicine.

RESULTS

At many institutions, the number of telemedicine visits dramatically increased within days following the institution of novel coronavirus pandemic restrictions on in-person clinical encounters. Prior to the pandemic, telemedicine utilization was weak throughout surgical specialties due to regulatory and reimbursement barriers. As part of the pandemic response, the USA government temporarily relaxed various telemedicine restrictions and provided additional telemedicine funding.

DISCUSSION

The post-pandemic role of telemedicine is dependent on permanent regulatory solutions. In the coming decade, telemedicine and telesurgery are anticipated to mature due to the proliferation of interconnected consumer health devices and high-speed 5G data connectivity.

Merkel Cell Carcinoma, Version 1.2018, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Guidelines for Merkel Cell Carcinoma (MCC) focuses on areas impacted by recently emerging data, including sections describing MCC risk factors, diagnosis, workup, follow-up, and management of advanced disease with radiation and systemic therapy. Included in these sections are discussion of the new recommendations for use of Merkel cell polyomavirus as a biomarker and new recommendations for use of checkpoint immunotherapies to treat metastatic or unresectable disease. The next update of the complete version of the NCCN Guidelines for MCC will include more detailed information about elements of pathology and addresses additional aspects of management of MCC, including surgical management of the primary tumor and draining nodal basin, radiation therapy as primary treatment, and management of recurrence.

Gastrointestinal Stromal Tumors of the Stomach and Esophagus

Gastrointestinal stromal tumors (GISTs) arise anywhere along the gastrointestinal tract, most commonly as a result of c-kit or PDGFRA proto-oncogene mutations. Surgical resection is an important component of treatment. However, molecular profiling of GISTs has provided many insights into adjuvant and neoadjuvant therapy options. Imatinib, the most frequently studied medical therapy, has been shown in numerous studies to provide benefit to patients in both the neoadjuvant and adjuvant setting. Interval imaging is an important component of the treatment of GISTs and national surveillance recommendations should be followed.

Healthcare disparities in outcomes of patients with resectable pancreatic cancer

BACKGROUND

The aim of this study was to evaluate health disparities in the outcomes of patients with resectable pancreatic adenocarcinoma.

METHODS

We retrospectively analyzed 280,935 patients from the National Cancer Data Base (NCDB), from 1998 to 2012 to compare the differences in patient characteristics, refusal of offered surgical treatment and overall survival after pancreatic adenocarcinoma resection between white vs. black patients.

RESULTS

Black patients did not undergo and refused offered surgical treatment more frequently. Race and insurance were the most important factors independently associated with not receiving the offered resection. Having private insurance, Hispanic ethnic background, geographic location, higher income, residing in urban/metropolitan area and systemic treatment were independently associated with improved survival. Race was associated with overall worse survival in an unadjusted model but not in multivariable analysis. The association between race and survival was removed when adjusting for facility location, income, education, tumor size, tumor stage or systemic treatment.

CONCLUSION

Disparities exist at various levels in resectable pancreatic cancers. These findings help developing targeted interventions and quality improvement initiatives.

Chemoproteomics-enabled covalent ligand screen reveals a cysteine hotspot in reticulon 4 that impairs ER morphology and cancer pathogenicity

Chemical genetics has arisen as a powerful approach for identifying novel anti-cancer agents. However, a major bottleneck of this approach is identifying the targets of lead compounds that arise from screens. Here, we coupled the synthesis and screening of fragment-based cysteine-reactive covalent ligands with activity-based protein profiling (ABPP) chemoproteomic approaches to identify compounds that impair colorectal cancer pathogenicity and map the druggable hotspots targeted by these hits. Through this coupled approach, we discovered a cysteine-reactive acrylamide DKM 3-30 that significantly impaired colorectal cancer cell pathogenicity through targeting C1101 on reticulon 4 (RTN4). While little is known about the role of RTN4 in colorectal cancer, this protein has been established as a critical mediator of endoplasmic reticulum tubular network formation. We show here that covalent modification of C1101 on RTN4 by DKM 3-30 or genetic knockdown of RTN4 impairs endoplasmic reticulum and nuclear envelope morphology as well as colorectal cancer pathogenicity. We thus put forth RTN4 as a potential novel colorectal cancer therapeutic target and reveal a unique druggable hotspot within RTN4 that can be targeted by covalent ligands to impair colorectal cancer pathogenicity. Our results underscore the utility of coupling the screening of fragment-based covalent ligands with isoTOP-ABPP platforms for mining the proteome for novel druggable nodes that can be targeted for cancer therapy.

Chronic granulomatous dermatitis induced by talimogene laherparepvec therapy of melanoma metastases

Talimogene laherparepvec (TVEC) is the first oncolytic viral immunotherapy approved by the FDA, for advanced melanoma consisting of genetically modified herpes simplex type 1 virus which selectively replicates causing tumor lysis, expressing granulocyte macrophage-colony stimulating factor (GM-CSF) and activating dendritic cells. Intratumoral injection of TVEC produces objective response in 41% of stage IIB-IV M1a melanoma. However, clinical response assessment can be problematic due to immune-related inflammation at established tumor sites. Herein, we report 5 cases of granulomatous dermatitis developing at sites of TVEC injection associated with pathologic complete response in 4 of 5 patients. Over 5 months, TVEC injections were administrated in a median of 20 tumors per patient for 9 median doses prior to biopsy of persistent, indurated nodules. Granulomatous dermatitis with melanophages and melanin pigment incontinence was observed in all samples without evidence of melanoma cells in 4 patients. The fifth patient was rendered melanoma-free by resection of the 1 nodule out of 4 with persistent tumor. Repetitive administration of TVEC or other oncolytic viral immunotherapies mimicking unresolved infection can produce granulomatous inflammation confounding assessment of the degree of tumor response and need for additional TVEC therapy. Tumor biopsies are encouraged after 4 to 6 months of TVEC administration to differentiate melanoma from granulomatous inflammation. Patients with confirmed granulomatous dermatitis replace continued with remained in remission after treatment discontinuation. Inflammatory nodules typically regress spontaneously.

Increased pancreatic cancer survival with greater lymph node retrieval in the National Cancer Data Base

BACKGROUND

We evaluated the role of lymph node (LN) retrieval in pancreatic adenocarcinoma (PA) patients undergoing pancreaticoduodenectomy (PD).

METHODS

We utilized the National Cancer Data Base; Cox regression models and logistic regression models were used for statistical evaluation.

RESULTS

We evaluated 26,792 patients with PA who underwent PD. The mean LN retrieved in LN(-) patients was 10.8 vs 14.4 for LN(+) patients (P < 0.0001). Greater LN retrieval is an independent predictor of a negative microscopic margin and decreased length of stay. The median survival of LN(-) patients exceeded that of LN(+) patients (24.5 vs 15.1 months, P < 0.0001). Increasing LN retrieval is a significant predictor of survival in all patients, and in LN(-) patients. The relationship of increased LN retrieval and enhanced survival is a nearly linear trend.

CONCLUSIONS

Rather than demonstrating an inflection point that defines the extent of adequate lymphadenectomy, this dataset demonstrates an incremental relationship between LN retrieval and survival.

Retrospective review of FOLFIRINOX in local advanced pancreatic cancer: Single institution experience

e15714

Background: Although combination of fluorouracil, irinotecan, Leucovorin and oxaliplatin [FOLFIRINOX] significantly increases survival in metastatic pancreatic cancer (MPC) compared to gemcitabine based on ACCORD trial, the efficacy and toxicities may be different in non-metastatic setting. We reviewed our institution’s experience with FOLFIRINOX in locally advanced pancreatic cancer (LAPC). Methods: We performed a retrospective review of clinical outcomes in patients diagnosed with LAPC and receiving between June 2010 and July 2015, with at least one year of follow up from diagnosis, at University of Alabama at Birmingham. Results: Total of 41 patients with ECOG performance scale of 0 or 1, who underwent neoadjuvant chemotherapy with FOLFIRINOX were assessed for clinical and pathological characteristics. Median age was 61 years (range 38-81) with 23 (56.1%) males, 28 (68.3%) Caucasians and 16 (39.0%) underwent surgery (whipple operation) post-neoadjuvant. Median OS (time of diagnosis to last follow up/death) is 83.5 months for whole cohort, survival rates are 94.9% at 1 year, 58.4% at 2 year, and 33.3% at 5 year.Median OS for those who underwent surgical resection following the chemotherapy is 38.6 months; 100% at one year, 85.1% at 2 year, 55.3% at 5 year; while median OS for those who did not undergo surgery is 21.8 months; 91.7% at one year, 41.5% at 2 year, 20.7% at 5 years. Among those who underwent surgery, the median recurrence free survival (time from surgery to relapse/progression) is 19.9 months with liver being common recurrence site (81%). There was no post-operative mortality in 30 days. Grade 3-4 toxicity occurred in 46% ( vomiting (12%), fatigue (28%) and neutropenia (54%), febrile neutropenia (9%)). There is a significant difference between surgery and non-surgery groups (p = 0.012) for improved OS by log-rank test. Conclusions: Neoadjuvant FOLFIRINOX treatment associated with high response rates leading to surgical resection in our cohort. Patients who underwent neoadjuvant chemotherapy followed by resection for LAPC have statistically significant improved OS compared to those who did not.

Chemoproteomic Screening of Covalent Ligands Reveals UBA5 As a Novel Pancreatic Cancer Target

Chemical genetic screening of small-molecule libraries has been a promising strategy for discovering unique and novel therapeutic compounds. However, identifying the targets of lead molecules that arise from these screens has remained a major bottleneck in understanding the mechanism of action of these compounds. Here, we have coupled the screening of a cysteine-reactive fragment-based covalent ligand library with an isotopic tandem orthogonal proteolysis-enabled activity-based protein profiling (isoTOP-ABPP) chemoproteomic platform to rapidly couple the discovery of lead small molecules that impair pancreatic cancer pathogenicity with the identification of druggable hotspots for potential cancer therapy. Through this coupled approach, we have discovered a covalent ligand DKM 2-93 that impairs pancreatic cancer cell survival and in vivo tumor growth through covalently modifying the catalytic cysteine of the ubiquitin-like modifier activating enzyme 5 (UBA5), thereby inhibiting its activity as a protein that activates the ubiquitin-like protein UFM1 to UFMylate proteins. We show that UBA5 is a novel pancreatic cancer therapeutic target and show DKM 2-93 as a relatively selective lead inhibitor of UBA5. Our results underscore the utility of coupling the screening of covalent ligand libraries with isoTOP-ABPP platforms for mining the proteome for druggable hotspots for cancer therapy.

Argininosuccinate Synthase 1 is a Metabolic Regulator of Colorectal Cancer Pathogenicity

Like many cancer types, colorectal cancers have dysregulated metabolism that promotes their pathogenic features. In this study, we used the activity-based protein profiling chemoproteomic platform to profile cysteine-reactive metabolic enzymes that are upregulated in primary human colorectal tumors. We identified argininosuccinate synthase 1 (ASS1) as an upregulated target in primary human colorectal tumors and show that pharmacological inhibition or genetic ablation of ASS1 impairs colorectal cancer pathogenicity. Using metabolomic profiling, we show that ASS1 inhibition leads to reductions in the levels of oncogenic metabolite fumarate, leading to impairments in glycolytic metabolism that supports colorectal cancer cell pathogenicity. We show here that ASS1 inhibitors may represent a novel therapeutic approach for attenuating colorectal cancer through compromising critical metabolic and metabolite signaling pathways and demonstrate the utility of coupling chemoproteomic and metabolomic strategies to map novel metabolic regulators of cancer.

Clinical outcomes of early-stage ampullary carcinoma: A single institutional experience

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Background: Ampullary carcinoma [AC] is a rare malignancy associated with favorable prognosis among pancreatobiliary tumors. Pancreaticoduodenectomy [PDY] is considered to be curative for early stage cancers. The role of adjuvant chemotherapy [CT] or combination chemoradiation [CRT] remains uncertain for stage I/II. In this analysis we reviewed our institution’s experience with AC. Methods: From 2005 to 2015, 62 patients with stage 1 and 2 AC with at least one year follow up after PDY were reviewed. Clinical and pathologic factors and disease status were obtained from chart review. The patients’ demographical and oncological characteristics are summarized. The univariate Cox proportional hazard model was conducted for evaluating the parameters associated with overall survival. Kaplan-Meier method and log-rank was used to compare the time-to-events. Results: Adjuvant treatment was administered in 61%: CT (32%), CRT (29%) 39% surgical alone. The median overall survival [OS] for the study cohort is 60 months with 3 yr OS at 58% and 5 yr OS at 50%. Recurrence noted in 21% of patients. About half of patients surviving five years were alive at 10 years. Lymph node [LN] metastases (57%) predicted worse PFS (HR 2.29, 95% CI (1.13-4.61), p = 0.021) but did not significantly affect OS (HR 1.2, 95% CI (0.84-3.61);p = 0.13). There were no postoperative deaths following surgery.Peri- pancreatic extension [PPE] (20%) and peri-neural invasion [PNI] (16%) was also found to be determinants for poor OS. Current data did not suggest lympho-vascular invasion (24%) predict OS (HR 1.20, 95% CI (0.49, 2.96);p = 0.63 or PFS(HR 1.45 (0.65, 3.20),p = 0.36). When compared to surgery alone adjuvant CT or CRT had no statistically significant difference in terms of PFS (p = 0.53) or OS (p = 0.96). Conclusions: The use of adjuvant treatment may be most useful at improving long-term disease control in patients with high-risk features; however, no significant difference between CT and CRT was demonstrated in our series. This could be due to small sample size and needs further validation in larger cohort. PDY with regional lymphadenectomy is appropriate for early-stage AC, but worst outcomes seen in patients with PPE, PNI and LN involvement.

Effect of nodal status compared to tumor response after neoadjuvant radiation on outcomes for patients with esophageal cancer

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Background: The CROSS trial established the role of neoadjuvant radiation in the treatment of esophageal adenocarcinoma (EAC). While response to radiation is an important factor in predicting long-term outcomes, the vast majority of patients succumb to systemic disease. The purpose of this study is to assess predictors of survival in patients with EAC following radiation therapy. Methods: All patients who underwent resection after radiation therapy for EAC at a single institution were retrospectively identified from January 2004 to December 2014. Patients who died within 30 days of surgery were excluded. Cox-proportional hazard analyses were performed to identify clinico-pathological factors associated with survival after surgery. Results: In the time period, 334 patients underwent esophagectomy for EAC. Univariable/multivariable analyses are shown in the table. The presence of a pathologic complete response (pCR) did not correlate to survival. The most important factors in predicting outcome were pre-operative albumin and initial lymph node stage by endoscopic ultrasound (EUS). Pre-treatment N0 patients had better survival than N1 patients (median survival 37.2 vs. 16.3 months, P < 0.0001). Patients who remained N0 after radiation had much better outcomes than those that either developed N1 disease after radiation or were initially staged as N1 (stayed N0, N = 126, median survival 52.0 months; N1→N0, N = 85, median survival 22.9 months; N0→N1, N = 30, median survival 15.3 months; persistent N1, N = 44, median survival 11.4 months; P < 0.0001). Conclusions: Pathologic response to radiation does not predict outcomes for patients with EAC. Patients with node positive EAC have poor outcomes even after neoadjuvant radiation therapy. These patients are at an increased risk of distant disease and should be offered additional systemic therapies prior to surgical resection. [Table: see text]

Improved survival after resection of liver and lung colorectal metastases compared with liver-only metastases: a study of 112 patients with limited lung metastatic disease

BACKGROUND

Lung metastases are considered a poor prognostic factor in patients with resectable colorectal liver metastases.

STUDY DESIGN

We reviewed records of 1,260 consecutive patients with liver-only or liver-plus-lung (L+L) metastases from colorectal cancer who underwent resection with curative intent (1995 to 2009). Survival and prognostic factors were analyzed.

RESULTS

There were 112 patients who underwent resection of L+L (mean 2 liver, 2 lung metastases). Mean tumor sizes were 3 cm and 1 cm, respectively. Thirty-four (31%) had bilateral lung metastases. Ten (9%) had synchronous L+L metastases, 60 (54%) had diagnosis of lung metastases within 1 year of liver resection. Most (108 of 112, 96%) had resection of liver before or at the same time as lung. Preoperative chemotherapy was used in 77 (69%) before liver resection and 56 (50%) before lung resection. Among L+L patients, no postoperative deaths occurred; postoperative morbidity rates were 26% after liver resection and 4% after lung resection. After a median of 49 months follow-up, L+L patients (n = 112) had better survival than liver only (n = 1,148) (5-year overall survival, L+L, 50% vs liver only, 40%; p = 0.01). CEA level > 5 ng/dL (hazard ratio [HR] 2.1, 95% CI 1.1 to 4.4, p = 0.04) and rectal primary (HR 2.9, 95% CI 1.4 to 6, p = 0.004) were associated with worse survival in L+L patients.

CONCLUSIONS

The survival rate for patients who undergo resection of L+L metastases from colorectal cancer is greater than the survival rate of the general population of patients who undergo resection of liver metastases only. The presence of resectable lung metastases is neither a poor prognostic factor nor a contraindication to resection of liver metastases.

Extended preoperative chemotherapy does not improve pathologic response and increases postoperative liver insufficiency after hepatic resection for colorectal liver metastases

BACKGROUND

The optimal duration, safety, and benefit of preoperative chemotherapy in patients with colorectal liver metastases (CLM) are unclear. We evaluated the association between the duration of preoperative chemotherapy with 5-fluorouracil (5-FU), leucovorin, oxaliplatin (FOLFOX) ± bevacizumab, pathologic response, and hepatotoxicity after hepatic resection for CLM.

METHODS

A total of 219 patients underwent hepatic resection following FOLFOX with or without bevacizumab and were divided into 2 groups according to the chemotherapy duration: 1-8 cycles (short duration [SD]; N = 157) and ≥9 cycles (long duration [LD]; N = 62). The frequency of complete or major pathologic response, sinusoidal injury, and major postoperative morbidity were compared.

RESULTS

Treatment consisting of ≥9 cycles was not associated with an increase in complete or major pathologic response (SD vs. LD, 57% vs. 55%; P = .74). The incidence of sinusoidal injury was higher in the LD group (26% vs. 42%; P = .017). The incidence of liver insufficiency was higher in the LD group (4% vs. 11%; P = .035). Sinusoidal injury did not predict postoperative liver insufficiency; multivariate analysis revealed ≥9 cycles was the only independent predictor of postoperative liver insufficiency (P = .031; odds ratio = 3.90). Chemotherapy including bevacizumab was associated with a significantly higher frequency of complete or major response in both SD and LD groups.

CONCLUSIONS

Extended preoperative chemotherapy increases the risk of hepatotoxicity in CLM without improving the pathologic response. The type of chemotherapy (FOLFOX with bevacizumab) has more impact on pathologic response than the duration of chemotherapy.

Staging laparoscopy enhances the detection of occult metastases in patients with pancreatic adenocarcinoma

BACKGROUND

The use of staging laparoscopy has been highly institutional dependent. We sought to assess the incidence of occult intra-abdominal metastases identified at the time of staging laparoscopy for patients with either potentially resectable or locally advanced pancreatic adenocarcinoma (LAPC). We also compared the rate of occult metastases in patients who underwent staging laparoscopy versus laparotomy.

METHODS

Patients were confirmed to have potentially resectable or LAPC at a multidisciplinary hepatopancreaticobiliary conference. Patients with potentially resectable lesions were initially explored via staging laparoscopy or laparotomy, based on surgeon preference.

RESULTS

Over a 4-year period, 25 patients with potentially resectable tumors and 33 patients with LAPC were staged with laparoscopy, with an equivalent prevalence of occult metastases found at laparoscopy (28% potentially resectable vs. 33% LAPC, P = 0.8). Fifty-two patients with potentially resectable lesions were explored initially via laparotomy. Occult peritoneal metastases were more likely to be detected in patients with potentially resectable tumors that were explored via laparoscopy than via laparotomy (32% vs. 10%, P = 0.018).

CONCLUSIONS

Staging laparoscopy is more likely than open exploration to detect occult metastases. Current preoperative imaging inadequately identifies unresectable pancreatic adenocarcinoma; therefore, all patients with potentially resectable disease should undergo staging laparoscopy.

A review of clinical and experimental observations about antidepressant actions and side effects produced by Hypericum perforatum extracts

Hypericum perforatum is an herbaceous perennial plant, also known as "St. John's wort", used popularly as a natural antidepressant. Although some clinical and experimental studies suggest it has some properties similar to conventional antidepressants, the proposed mechanism of action seems to be multiple: a non-selective blockade of the reuptake of serotonin, noradrenaline and dopamine; an increase in density of serotonergic and dopaminergic receptors and an increased affinity for GABAergic receptors; moreover, the inhibition of monoaminoxidase enzyme activity has been involved. In any case, the increase of monoamine concentrations in the synaptic cleft resembles several actions exerted by clinically effective antidepressants. In the present article, we review some of the controversial evidence derived from clinical and experimental studies suggesting that H. perforatum exerts antidepressant-like actions, and we also review some of its side effects, such as nausea, rash, fatigue, restlessness, photosensitivity, acute neuropathy, and even episodes of mania and serotonergic syndrome when administered simultaneously with other antidepressant drugs. All of the foregoing suggests that H. perforatum extracts appear to exert potentially significant pharmacological activity involving several neurotransmission systems supposed to be involved in the pathophysiology of depression. However, little information regarding the safety of H. perforatum is available, including potential herb-drug interactions. There is a need for additional research on the pharmacological and biochemical activity of H. perforatum, as well as its side-effects and its several bioactive constituents to further elucidate the mechanisms of antidepressant actions.

The lowest effective dose of fluoxetine in the forced swim test significantly affects the firing rate of lateral septal nucleus neurones in the rat

The administration of a relatively high dose of antidepressant drugs produces an increased neuronal firing rate of the lateral septal nucleus (LSN) in the rat and a decreased immobility in rats forced to swim. However, it is unknown whether a minimally effective low-dose 21-day treatment with the selective serotonin reuptake inhibitor, fluoxetine, while reducing immobility in the forced swim test, also increases the neuronal firing rate of the LSN in Wistar rats. The total time of immobility decreased with a daily injection of 0.5, 1.0 or 2.0 mg/kg of fluoxetine (p < 0.001), and the lowest dose increasing the latency to the first immobility period (p < 0.0001) was 1.0 mg/kg. Therefore, the action of the 21-day fluoxetine treatment (1.0 mg/kg) on the firing rate of LSN neurones was tested in another group of rats. A total amount of 78 single-unit extracellular recordings was taken from the LSN of eight control rats (n = 40) and eight fluoxetine treated rats (n = 38). The LSN firing rate in the fluoxetine group was double (18.3 +/- 2.5 spikes per 10 s, p < 0.05) that in the control group (7.0 +/- 0.9 spikes per 10 s), and the first order interval of firing proved to be significantly lower in the fluoxetine group compared to the control group (384.3 +/- 22.3 and 639.7 +/- 27.5 ms, respectively; p < 0.05). In conclusion, the increased neuronal tiring rate of the LSN in the animals treated with a low dose of fluoxetine may be associated with an increased motivation to escape from the stressful situation that the forced swim represents.

Diazepam increases the number of punished responses in a conflict-operant paradigm during late proestrus and estrus in the Wistar rat

Both anxiety-like behavior and the response to anxiolytic drugs vary according to the estrus cycle in the rat. Consequently, anxiety-like behavior and the sensitivity to anxiolytic drugs may be related to hormone level fluctuations occurring during the estrus cycle. In male rats tested in a conflict-operant paradigm, anxiolytic drugs increase immediate punished responding. However, it is unknown whether estrus phases impinge on the immediate punished responses in a conflict-operant paradigm. Therefore, in this study female rats were trained in a conflict-operant paradigm; after training all animals received vehicle or diazepam. Then the number of immediate punished reinforcers was evaluated during the estrus cycle. Results showed that vehicle-treated rats evaluated during late proestrus and estrus obtained a higher (p < 0.05) number of immediate punished reinforcers than rats evaluated during metestrus and diestrus. A low dose of diazepam (1.3 mg/kg; i.p) significantly increased (p < 0.05) the immediate punished responses only in late proestrus and estrus. The highest dose of diazepam tested (2.0 mg/kg; i.p.) significantly increased (p < 0.05) the immediate punished reinforcement in any estrus phase. These results suggest that a lower level of anxiety-like and an increased sensitivity to an anxiolytic drug occurred only in late proestrus and estrus in rats tested in a conflict-operant paradigm.

Antidepressant-like effects of pregnancy and progesterone in Wistar rats as measured in the differential reinforcement of the low-rate 72 s task

RATIONALE

In rats, several behavioral changes occurring during pregnancy could be due to the presence of progesterone; some of them may be analyzed in the differential reinforcement of the low-rate 72 s task (DRL-72 s), which is designed for testing the antidepressant profile of drugs.

OBJECTIVES

The aim of the present study was to analyze the behavior of pregnant rats or ovariectomized rats receiving exogenous progesterone in the DRL-72 s task.

HYPOTHESIS

During pregnancy, rats will obtain a high number of reinforcers in the DRL-72 s task.

METHODS

Pregnant rats or rats after delivery were tested in the DRL-72 s task at the 3rd, 7th, 14th, 17th, and 20th days. Control rats previously trained in the DRL-72 s task were ovariectomized; after recuperation, they received saline (0.9%, i.p.), clomipramine (1.25 mg/kg, i.p.), or desipramine (2.14 mg/kg, i.p.) for 28 days, and they were tested in the DRL-72 s task. In a second series of experiments, ovariectomized rats received vehicle or progesterone (0.5, 1.0, 2.0, 4.0 mg/kg, s.c.), and they were submitted to the DRL-72 s task. Locomotion was evaluated in the open field test.

RESULTS

Pregnant rats tested at the 14th and 17th day and ovariectomized rats receiving progesterone or two tricyclic antidepressants obtained a higher number of reinforcers and a cohesive rightward shift in inter-response time distributions than those rats evaluated after delivery in the DRL-72 s task. A lower locomotion was observed only at the end of pregnancy.

CONCLUSIONS

Antidepressant-like effects of pregnancy and progesterone were found in Wistar rats as measured in the DRL-72 s task.

Purification and bioassays of a diuretic and natriuretic fraction from garlic (Allium sativum)

The intravenous administration of a purified fraction (6 microg/kg) to anaesthesized dogs was followed by a significant biphasic diuretic and natriuretic response which reached a maximum at 180 min after injection. Chloride, but not potassium ions, followed the natriuretic profile. No changes were observed in arterial blood pressure or in the electrocardiogram. The purified garlic fraction also induced an inhibitory dose-dependent effect on kidney Na, K-ATPase.

Interaction of desipramine with steroid hormones on experimental anxiety

The present study analyzes if estradiol benzoate and/or progesterone interact with desmethylimipramine (DMI) to diminish experimental anxiety. The animal model of anxiety used was the conditioned defensive burying test. Dose response curves for DMI (0.625, 1.25 and 2.5 mg/kg, every 24 h, during 21 days), estradiol benzoate (0.5, 1.0, 2.0 and 4.0 micrograms/rat, 48 h) and progesterone (0.5, 1.0 and 2.0 mg/rat, -4 h) were made in ovariectomized rats. DMI per se decreased dose dependently the cumulative burying time, an effect considered as anxiolytic-like. Progesterone produced a decrease in burying at the highest dose, while estradiol benzoate had no effect on defensive burying. Both, progesterone (0.5 mg/rat) and estradiol benzoate (4.0 micrograms/rat) were able to decrease the cumulative burying behavior when injected with a subthreshold dose of DMI (1.25 mg/kg). In addition, the effect of DMI (1.25 mg/kg) plus the combination of estradiol benzoate and progesterone, sequentially administered (48 h and 4 h before the tests, respectively), also produced a synergistic decrease in burying behavior. In general, the treatments produced no changes in burying behavior latency, neither in spontaneous ambulation or in nociception. It is concluded that DMI synergizes its anxiolytic-like effect when administered with estradiol alone or in combination with progesterone. Present data provide experimental evidence suggesting an interaction between hormones and antidepressants. Results are discussed on the basis of the interaction between steroids and serotonergic or GABAergic receptors.

Lateral septal neuronal firing rate increases during proestrus-estrus in the rat

Neuronal activity of the lateral septal nucleus (LSN) is related to motivational and hedonic behavior. Even though some changes in mood and anxiety during proestrus and pregnancy have been reported, the possible changes in the neuronal activity of the LSN through the phases of the estrous cycle are unknown. In the present study we explored the neuronal activity from the LSN using glass micropipettes (NaCl 1 M, and Evans blue 2.5%; 3-8 Mohms in 30 urethane (1 g/kg) anesthetized Wistar rats. Analysis of data included a total of 88 single-unit extracellular recordings taken from the LSN during proestrus (n = 22), estrus (n = 23), diestrus (n = 22), and metestrus (n = 21). The highest values of firing rate were found in proestrus, and the lowest in metestrus, F(3,84) = 3.78, p < 0.01. During estrous cycles, in the phase characterized by high plasma levels of estradiol and progesterone, i.e., proestrus-estrus, the neurons from the dorsal aspect of the LSN fired at significantly (p < 0.05) higher frequencies, shorter first-order intervals and a lower coefficient of variation than those in the phase characterized by lower levels of estradiol and progesterone (metestrus-diestrus). In another group of rats (n = 12), immobility in the forced-swim test was assessed. Consistently, a longer latency (p < 0.05) for the first period of immobility and a nonsignificant trend to a lowered total time in immobility were found in proestrus and estrus. It is concluded that the higher firing rate in neurons from the dorsal aspect of the LSN during proestrus-estrus, may be associated with an increased motivation to escape from a stressful situation.

Mimosa pudica may possess antidepressant actions in the rat

In Mexico, aqueous extracts from dried leaves of Mimosa puolica are employed to alleviate depression. In this study, the behavioral actions of aqueous extracts of M. pudica at various concentrations were tested. Rats having received saline (0.9%; 0.30 ml; I.P.), clomipramine, desipramine or several dosages of aqueous extracts from M. pudica (ml = 2.0 mg/kg; m2 = 4.0 mg/kg; m3 = 6.0 mg/kg; m4 = 8.0 mg/kg) during a 30-day period were submitted to the forced swimming test and to the test for differential reinforcement of low rates of response at 72 sec (DRL-72s). Any possible anxiolytic action resulting from several doses (ml = 2.0 mg/kg; m2 = 4.0 mg/kg; m3 = 6.0 mg/kg; m4 = 8.0 mg/kg) of extracts of M. pudica were compared with those caused by diazepam (1.3 mg/kg, I.P.) in the elevated plus-maze test. Results showed that clomipramine (1.25 mg/kg, I.P.), desipramine (2.14 mg/kg, I.P.) and M. pudica (6.0 mg/kg and 8.0 mg/kg, I.P.) reduced immobility in the forced swimming test and increased the rate of reinforcers received in the DRL-72s test; these data suggest that M. pudica produces antidepressant effects in the rat. Diazepam increased the open-arms exploration time in the elevated plus-maze test, but M. pudica did not show any comparable action at any tested dose. M. pudica therefore produced an antide-pressant-like profile similar to two tricyclic antidepressants.

Progesterone reduces immobility in rats forced to swim

BACKGROUND

Among its behavioral actions, progesterone reduces anxiety in several species including humans; however, any antidepressant-like properties remain to be explored.

METHODS

In the present study, Wistar rats received injections (i.p.) of progesterone (0.20-3.0 mg/kg) 24 and 2 h before being submitted to the forced swim, a test in which antidepressants regularly reduce immobility and exert few or no actions on locomotor activity. In order to discard the cumulative effects of progesterone and a possible effect from the repetition of the swimming test, all animals received one of several progesterone doses in a different sequence following a completely randomized experimental intrasubject design.

RESULTS

Ovariectomy did not modify immobility in the forced swim test as compared to control tests practiced before surgery. A dose of 0.80 mg/kg strongly reduced the total time of immobility in forced swim test (p < 0.001), but did not modify locomotor activity. In a drug-free control test applied 1 week after the last injection of progesterone, immobility returned to the higher values observed in the control tests.

CONCLUSIONS

From these results, it is concluded that progesterone may possess some anti-depressant-like activity.

Sedative actions of Ternstroemia sylvatica in the male rat

Ternstroemia sylvatica is a plant reputed popularly to possess a anxiolytic properties but has not yet been systematically tested for such activity. The behavioral actions of T. sylvatica were examined using the open field test, the elevated plus-maze test, and the forced swim test in male rats. T. sylvatica (7.1 mg/kg and 14.2 mg/kg, i.p.) reduced ambulatory behavior in the open field test and cancelled the anti-immobility actions produced by desipramine (32 mg/kg, i.p.) in the forced swim test, as did diazepam. In the elevated plus-maze test, T. sylvatica (7.1 mg/kg, i.p.) failed to show anxiolytic actions. It is concluded that Ternstroemia sylvatica produces sedative effects rather than the attributed anxiolytic actions.

In vitro recoating of reovirus cores with baculovirus-expressed outer-capsid proteins mu1 and sigma3

Reovirus outer-capsid proteins mu1, sigma3, and sigma1 are thought to be assembled onto nascent core-like particles within infected cells, leading to the production of progeny virions. Consistent with this model, we report the in vitro assembly of baculovirus-expressed mu1 and sigma3 onto purified cores that lack mu1, sigma3, and sigma1. The resulting particles (recoated cores, or r-cores) closely resembled native virions in protein composition (except for lacking cell attachment protein sigma1), buoyant density, and particle morphology by scanning cryoelectron microscopy. Transmission cryoelectron microscopy and image reconstruction of r-cores confirmed that they closely resembled virions in the structure of the outer capsid and revealed that assembly of mu1 and sigma3 onto cores had induced rearrangement of the pentameric lambda2 turrets into a conformation approximating that in virions. r-cores, like virions, underwent proteolytic conversion to particles resembling native ISVPs (infectious subvirion particles) in protein composition, particle morphology, and capacity to permeabilize membranes in vitro. r-cores were 250- to 500-fold more infectious than cores in murine L cells and, like virions but not ISVPs or cores, were inhibited from productively infecting these cells by the presence of either NH4Cl or E-64. The latter results suggest that r-cores and virions used similar routes of entry into L cells, including processing by lysosomal cysteine proteinases, even though the former particles lacked the sigma1 protein. To examine the utility of r-cores for genetic dissections of mu1 functions in reovirus entry, we generated r-cores containing a mutant form of mu1 that had been engineered to resist cleavage at the delta:phi junction during conversion to ISVP-like particles by chymotrypsin in vitro. Despite their deficit in delta:phi cleavage, these ISVP-like particles were fully competent to permeabilize membranes in vitro and to infect L cells in the presence of NH4Cl, providing new evidence that this cleavage is dispensable for productive infection.

Chronic treatment with desipramine induces an estrous cycle-dependent anxiolytic-like action in the burying behavior, but not in the elevated plus-maze test

The effect of chronic desipramine (DMI, 2.5 mg/kg x 21-26 days) treatment in female rats in two anxiety paradigms was assessed: the burying behavior (BB) and the elevated plus-maze (EPM) tests. In the BB test DMI produced a significant decrease in burying in ovariectomized rats, an effect considered as anxiolytic-like. In cycling females, DMI also reduced the cumulative BB most notably in proestrus rats. However, in diestrus rats no anxiolytic-like actions were observed. In addition, DMI increased BB latencies in proestrus and estrus rats. In the EPM test, DMI produced anxiolytic-like actions only in ovariectomized rats, while no significant actions were found in cycling females. Finally, the chronic treatment with DMI produced a general reduction in the ambulatory behavior of rats in all estrous cycle phases. Results are discussed on the basis of the differences between both anxiety paradigms and the probable relationship between the steroids secreted during proestrus and chronic DMI treatment.

Desipramine restricts estral cycle oscillations in swimming

1. Desipramine (DMI) is a tricyclic antidepressant which reduces the immobility in rats forced to swim; however, it is unknown whether estral cycle phases impinge on DMI actions on immobility in daily swimming tests during several weeks. 2. In female wistar rats, vaginal smears taken before testing defined four estral phases. Afterwards, the authors assessed the latency for the first period of immobility in five-min forced swim tests practiced on 21-day DMI (DMI group), 21-day washout saline given after a 21-day DMI treatment (washout-saline group), or non-treated rats (control group). 3. We observed a longer latency for the first period of immobility in proestrus-estrus from the control and washout-saline groups. The 21-day treatment with DMI (2.1 mg/kg i.p., once a day) significantly (p < 0.001) increased the latency by about 160% from control regardless of the estral cycle phase. 4. It is concluded that proestrus-estrus relates to increased struggling behavior. DMI enhances struggling behavior independently of hormonal state.