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1.
J Surg Res ; 299: 329-335, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38788470

ABSTRACT

INTRODUCTION: Chat Generative Pretrained Transformer (ChatGPT) is a large language model capable of generating human-like text. This study sought to evaluate ChatGPT's performance on Surgical Council on Resident Education (SCORE) self-assessment questions. METHODS: General surgery multiple choice questions were randomly selected from the SCORE question bank. ChatGPT (GPT-3.5, April-May 2023) evaluated questions and responses were recorded. RESULTS: ChatGPT correctly answered 123 of 200 questions (62%). ChatGPT scored lowest on biliary (2/8 questions correct, 25%), surgical critical care (3/10, 30%), general abdomen (1/3, 33%), and pancreas (1/3, 33%) topics. ChatGPT scored higher on biostatistics (4/4 correct, 100%), fluid/electrolytes/acid-base (4/4, 100%), and small intestine (8/9, 89%) questions. ChatGPT answered questions with thorough and structured support for its answers. It scored 56% on ethics questions and provided coherent explanations regarding end-of-life discussions, communication with coworkers and patients, and informed consent. For many questions answered incorrectly, ChatGPT provided cogent, yet factually incorrect descriptions, including anatomy and steps of operations. In two instances, it gave a correct explanation but chose the wrong answer. It did not answer two questions, stating it needed additional information to determine the next best step in treatment. CONCLUSIONS: ChatGPT answered 62% of SCORE questions correctly. It performed better at questions requiring standard recall but struggled with higher-level questions that required complex clinical decision making, despite providing detailed responses behind its rationale. Due to its mediocre performance on this question set and sometimes confidently-worded, yet factually inaccurate responses, caution should be used when interpreting ChatGPT's answers to general surgery questions.


Subject(s)
General Surgery , Internship and Residency , Humans , General Surgery/education , Educational Measurement/methods , Educational Measurement/statistics & numerical data , United States , Clinical Competence/statistics & numerical data , Specialty Boards
2.
J Surg Res ; 298: 269-276, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38636183

ABSTRACT

INTRODUCTION: Despite improvements in preoperative image resolution, approximately 10% of curative-intent resection attempts for pancreatic ductal adenocarcinoma are aborted at the time of operation. To avoid nontherapeutic laparotomy, many surgeons perform intraoperative diagnostic laparoscopy (DL) to identify radiographically occult metastatic disease. There are no consensus guidelines regarding DL in pancreatic cancer. The goal of this study is to investigate the efficacy of same-procedure DL at avoiding nontherapeutic laparotomy. METHODS: A single-institution retrospective review was performed from 2016 to 2022, identifying 196 patients with pancreatic ductal adenocarcinoma who were taken to the operating room for open curative-intent resection. Patient demographic, tumor characteristic, treatment, and outcome data were abstracted. Univariate and multivariate Cox hazard ratio analysis was performed to investigate risk factors for overall survival and recurrence-free survival. Number needed to treat (NNT) was calculated to identify number of DLs necessary to avoid one nontherapeutic laparotomy. RESULTS: Curative-intent resection was achieved in 161 (82.1%) patients. One hundred twenty six (64.0%) patients received DL prior to resection and DL identified metastatic disease in three (2.4%) patients with an NNT of 42. NNT of DL in a subgroup analysis performed on clinically high-risk patients (defined by preoperative or preneoadjuvant therapy carbohydrate antigen 19-9 > 500 U/mL) is 11. Receipt of DL did not prolong operative times in patients receiving pancreaticoduodenectomy when accounting for completed versus aborted resection. CONCLUSIONS: Although intraoperative DL is a short procedure with minimal morbidity, these data demonstrate that same-procedure DL has potential efficacy in avoiding nontherapeutic laparotomy only in a subgroup of clinically high-risk patients. Focus should remain on optimizing preoperative patient selection and further investigating novel diagnostic markers predictive of occult metastatic disease.


Subject(s)
Carcinoma, Pancreatic Ductal , Laparoscopy , Pancreatic Neoplasms , Humans , Laparoscopy/methods , Laparoscopy/statistics & numerical data , Female , Retrospective Studies , Male , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/pathology , Aged , Middle Aged , Carcinoma, Pancreatic Ductal/surgery , Carcinoma, Pancreatic Ductal/diagnosis , Carcinoma, Pancreatic Ductal/mortality , Pancreatectomy , Aged, 80 and over , Adult
3.
Am J Surg ; 223(5): 939-944, 2022 05.
Article in English | MEDLINE | ID: mdl-34474917

ABSTRACT

BACKGROUND: A minority of patients with gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) is diagnosed at younger age. This population-based study explores the broad clinical and pathologic features of the youngest 5% of adult patients with GEP-NETs. METHODS: A retrospective study of the National Cancer Database (NCDB) of patients with a primary GEP-NET was performed. Patients were stratified by age. Kaplan-Meier and multivariate Cox proportional hazards analyses were performed. RESULTS: We identified 31,983 patients with a diagnosis of a GEP-NET and only 5% of patients were under the age of 35. Young patients were found to have greater proportions of localized, well differentiated disease. On multivariate analysis, young age, well differentiated histology, early stage, and surgical intervention were associated with lower risk of mortality. CONCLUSIONS: Young patients with GEP-NETs tend to have earlier stage of presentation and well differentiated tumors, which may be most amenable to surgical intervention.


Subject(s)
Intestinal Neoplasms , Neuroendocrine Tumors , Pancreatic Neoplasms , Stomach Neoplasms , Humans , Intestinal Neoplasms/pathology , Neuroendocrine Tumors/surgery , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/surgery , Retrospective Studies , Stomach Neoplasms/pathology , Young Adult
4.
Ann Surg Oncol ; 27(13): 5240-5247, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32909128

ABSTRACT

BACKGROUND: Melanoma of unknown primary (MUP) accounts for approximately 3% of melanoma diagnoses. This study sought to evaluate treatment and outcomes for a modern MUP cohort. METHODS: A retrospective review of MUP was performed at a tertiary referral cancer center. RESULTS: Of 815 melanoma patients, 67 (8.2%) had MUP. Men were more likely to have MUP than women (67% vs. 55%; p = 0.04). The most common sites of MUP were lymph nodes (28%), visceral solid organs (25%), brain (16%), and skin/subcutaneous tissues (10%). Of the patients who underwent tumor genomic profiling, 52% harbored pathogenic BRAF mutations. Of the 24 patients who underwent multi-gene panel testing, all had pathogenic mutations and 21 (88%) had mutations in addition to or exclusive of BRAF, including 11 patients (46%) with telomerase reverse transcriptase promoter mutations. Checkpoint inhibitors (39%) and BRAF-MEK inhibitors (7%) were the most common first-line treatments. Upfront surgical resection was used for 25% of the MUP patients, and 12 of these resections were for curative intent. During a median follow-up period of 22.1 months, the median overall survival (OS) was not met for the patients with MUP isolated to lymph nodes. At 56.8 months, 75% of these patients were alive. The median OS was 37.4 months for skin/soft tissue MUP, 33.3 months for single solid organ viscera MUP, and 29.8 months for metastatic brain MUP. CONCLUSION: Multigene panel testing identified pathogenic mutations in all tested MUP patients and frequently identified targets outside BRAF. Despite advanced stage, aggressive multimodal therapy for MUP can be associated with 5-year OS and should be pursued for appropriate candidates.


Subject(s)
Melanoma , Neoplasms, Unknown Primary , Skin Neoplasms , Female , Humans , Lymph Nodes , Male , Melanoma/genetics , Melanoma/therapy , Mutation , Neoplasms, Unknown Primary/genetics , Neoplasms, Unknown Primary/therapy , Proto-Oncogene Proteins B-raf/genetics , Retrospective Studies , Skin Neoplasms/genetics , Skin Neoplasms/therapy
5.
Ann Surg Oncol ; 27(10): 3754-3761, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32712891

ABSTRACT

BACKGROUND: Recent reviews of medical conferences have shown that women were less likely to receive a formal introduction compared with men. We examined speaker introductions at the Society of Surgical Oncology (SSO) annual meeting to determine whether similar biases exist within our organization. METHODS: An observational study of video-archived speaker introductions at the 2018 and 2019 SSO annual meetings was conducted. Professional address was defined as professional title followed by full name or last name. Multivariable logistic regression was used to identify factors associated with form of address. RESULTS: There were 499 speaker introductions reviewed. Speakers included 290 (58%) men and 238 (49%) post-graduate trainees (residents and fellows). A non-professional form of address was used to introduce 148 (30%) speakers and was most often used for post-graduate trainees (33%). Full professors were more likely than junior faculty to introduce speakers with a non-professional form of address (37% of full professors vs 18% of assistant professors, p < 0.001). In multivariable regression analysis these findings persisted. Trainees were 2.8 times more likely to receive a non-professional form of address (p = 0.003). Use of a non-professional introduction did not significantly vary by the speaker's nor the introducer's gender. CONCLUSIONS: Residents and fellows were more likely to receive a non-professional form of address, and the likelihood of this increased with rising seniority of the introducer. The manner of speaker introduction did not vary by gender in our organization. More research is needed to explore the influence of these disparities on academic advancement for the next generation of surgical oncologists.


Subject(s)
Neoplasms , Sexism , Surgical Oncology , Female , Humans , Male , Neoplasms/surgery
6.
Front Endocrinol (Lausanne) ; 11: 624251, 2020.
Article in English | MEDLINE | ID: mdl-33613455

ABSTRACT

Renal neuroendocrine neoplasms are rare, with descriptions of cases limited to individual reports and small series. The natural history of this group of neuroendocrine neoplasms is poorly understood. In this study, we queried the Surveillance, Epidemiology and End Results (SEER) database over a four-decade period where we identified 166 cases of primary renal neuroendocrine neoplasms. We observed a 5-year overall survival of 50%. On multivariate analysis, survival was influenced by stage, histology, and if surgery was performed. We observed that patients managed by operative management had a greater frequency of localized or regional stage disease as well as a greater frequency of neuroendocrine tumor, grade 1 histology; whereas those managed non-operatively tended to have distant disease and histologies of neuroendocrine carcinoma, NOS and small cell neuroendocrine carcinoma. This is the largest description of patients with renal neuroendocrine neoplasms. Increased survival was observed in patients with earlier stage and favorable histologies.


Subject(s)
Kidney Neoplasms/classification , Kidney Neoplasms/mortality , Neuroendocrine Tumors/classification , Neuroendocrine Tumors/mortality , SEER Program/trends , Adult , Aged , Female , Humans , Kidney Neoplasms/diagnosis , Male , Middle Aged , Multivariate Analysis , Neuroendocrine Tumors/diagnosis , Survival Rate/trends
7.
Am Surg ; 85(10): 1125-1128, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31657307

ABSTRACT

Neuroendocrine tumors (NETs) are the most common malignancy arising in Meckel's diverticula (MDs). To date, there are no large series characterizing these tumors. The National Cancer Database was queried for patients with MD NETs (n = 162) from 2004 to 2014. Patient and tumor characteristics as well as outcomes were analyzed. MD NETs were more common in men (72.8%) at a median age of 62 years; 95.1 per cent of patients were white. All patients underwent surgery. Clinical M0 disease was present in 97.4 per cent of patients, and 88.2 per cent of tumors were well differentiated. Lymphovascular invasion was present in 13.2 per cent. Most (60.4%) tumors were less than 10 mm. Lymphadenectomy was performed in 32.9 per cent of patients, with 52.1 per cent of these found to have metastatic lymph node disease. Although most MD NETs are well differentiated, smaller than 10 mm, and do not have lymphovascular invasion, lymph node metastases are commonly found, suggesting that mesenteric lymphadenectomy with adequate resection of the small bowel may be necessary for adequate staging and disease clearance.


Subject(s)
Ileal Neoplasms/etiology , Meckel Diverticulum/complications , Neuroendocrine Tumors/etiology , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Humans , Ileal Neoplasms/epidemiology , Ileal Neoplasms/pathology , Ileal Neoplasms/surgery , Kaplan-Meier Estimate , Lymph Node Excision/statistics & numerical data , Lymphatic Metastasis , Male , Meckel Diverticulum/epidemiology , Middle Aged , Neuroendocrine Tumors/epidemiology , Neuroendocrine Tumors/pathology , Neuroendocrine Tumors/surgery , SEER Program/statistics & numerical data , Sex Distribution , Tumor Burden
8.
J Surg Oncol ; 119(5): 653-659, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30811033

ABSTRACT

Liver metastases and peritoneal carcinomatosis are a particular focus of surgeons in improving survival in stage IV colorectal cancer patients, with laparotomy long being the means to undertake these operations. The Louisville statement published in 2008 was the first international consensus on indications for minimally invasive liver resection. Herein we review the progress in innovative surgical techniques, including minimally invasive liver resection, robot-assisted hepatectomy, and we also describe initial reports in pressurized intraperitoneal aerosol chemotherapy.


Subject(s)
Colorectal Neoplasms/pathology , Hepatectomy/methods , Liver Neoplasms/secondary , Liver Neoplasms/surgery , Aerosols , Antineoplastic Agents/administration & dosage , Colorectal Neoplasms/surgery , Humans , Laparoscopy , Robotic Surgical Procedures
9.
Ann Surg Oncol ; 25(10): 3004-3010, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30030731

ABSTRACT

BACKGROUND: Access to health care poses particular challenges for patients living in rural communities. Intraoperative radiotherapy (IORT) offers a treatment alternative to traditional whole-breast radiation therapy (WBRT) for select patients. This study aimed to analyze the use of IORT for patients undergoing breast-conserving surgery at an academic institution located in a rural state. METHODS: A retrospective review analyzed all patients at a single institution with a diagnosis of ductal carcinoma in situ (DCIS) or invasive breast cancer from April 2012 to January 2017 who were undergoing breast-conserving surgery with either IORT or WBRT. Student's t test or Fisher's exact test was used to make statistical comparisons. RESULTS: Patients undergoing IORT (n = 117) were significantly older than patients treated with WBRT (n = 191) (65.6 vs 58.6 years; p < 0.001) and had smaller tumors on both preoperative imaging (1.04 vs 1.66 cm; p < 0.05) and final pathology (0.99 vs 1.48 cm; p < 0.05). Patients receiving IORT lived farther from the treating facility than patients treated with WBRT (67.2 vs 30.8 miles; p < 0.05). To account for biases created in the IORT selection criteria, subgroup analysis was performed for women receiving WBRT who fulfilled IORT selection criteria, and distance traveled remained significant (67.2 vs 31.4 miles; p < 0.05). Neither recurrence nor survival differed between the IORT and WBRT groups. Medicare reimbursement for IORT was approximately 50% more than for WBRT. CONCLUSIONS: For women from rural communities, IORT appears to be an attractive option because these women tend to be older and to live farther from the treatment facility.


Subject(s)
Breast Neoplasms/therapy , Carcinoma, Ductal, Breast/therapy , Carcinoma, Lobular/therapy , Intraoperative Care , Mastectomy, Segmental/methods , Neoplasm Recurrence, Local/diagnosis , Radiotherapy , Aged , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Lobular/pathology , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Iowa/epidemiology , Middle Aged , Neoplasm Recurrence, Local/epidemiology , Prognosis , Retrospective Studies , Rural Population
10.
Oncotarget ; 8(70): 114801-114815, 2017 Dec 29.
Article in English | MEDLINE | ID: mdl-29383121

ABSTRACT

Cancer stem cells (CSCs) are expanded in anaplastic thyroid cancer (ATC) and standard treatment approaches have failed to improve survival, suggesting a need to specifically target the CSC population. Recent studies in breast and colorectal cancer demonstrated that inhibition of the SUMO pathway repressed CD44 and cleared the CSC population, mediated through SUMO-unconjugated TFAP2A. We sought to evaluate effects of inhibiting the SUMO pathway in ATC. ATC cell lines and primary ATC tumor samples were evaluated. The SUMO pathway was inhibited by knockdown of PIAS1 and use of SUMO inhibitors anacardic acid and PYR-41. The expression of TFAP2A in primary ATC was examined by immunohistochemistry. All ATC cell lines expressed TFAP2A but only 8505C expressed SUMO-conjugated TFAP2A. In 8505C only, inhibition of the SUMO pathway by knockdown of PIAS1 or treatment with SUMO inhibitors repressed expression of CD44 with a concomitant loss of SUMO-conjugated TFAP2A. The effect of SUMO inhibition on CD44 expression was dependent upon TFAP2A. Treatment with SUMO inhibitors resulted in a statistically improved tumor-free survival in mice harboring 8505C xenografts. An examination of primary ATC tissue determined that TFAP2A was expressed in 4 of 11 tumors surveyed. We conclude that inhibition of the SUMO pathway repressed the CSC population, delaying the outgrowth of tumor xenografts in ATC. The effect of SUMO inhibition was dependent upon expression of SUMO-conjugated TFAP2A, which may serve as a molecular marker for therapeutic effects of SUMO inhibitors. The findings provide pre-clinical evidence for development of SUMO inhibitors for the treatment of ATC.

11.
Stem Cell Reports ; 7(6): 1140-1151, 2016 12 13.
Article in English | MEDLINE | ID: mdl-27916539

ABSTRACT

Many solid cancers have an expanded CD44+/hi/CD24-/low cancer stem cell (CSC) population, which are relatively chemoresistant and drive recurrence and metastasis. Achieving a more durable response requires the development of therapies that specifically target CSCs. Recent evidence indicated that inhibiting the SUMO pathway repressed tumor growth and invasiveness, although the mechanism has yet to be clarified. Here, we demonstrate that inhibition of the SUMO pathway repressed MMP14 and CD44 with a concomitant reduction in cell invasiveness and functional loss of CSCs in basal breast cancer. Similar effects were demonstrated with a panel of E1 and E3 SUMO inhibitors. Identical results were obtained in a colorectal cancer cell line and primary colon cancer cells. In both breast and colon cancer, SUMO-unconjugated TFAP2A mediated the effects of SUMO inhibition. These data support the development of SUMO inhibitors as an approach to specifically target the CSC population in breast and colorectal cancer.


Subject(s)
Breast Neoplasms/pathology , Colorectal Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Signal Transduction , Small Ubiquitin-Related Modifier Proteins/metabolism , Anacardic Acids/chemistry , Anacardic Acids/pharmacology , Breast Neoplasms/metabolism , Carcinogenesis/drug effects , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Line, Tumor , Colorectal Neoplasms/metabolism , Female , Gene Knockdown Techniques , Humans , Hyaluronan Receptors/metabolism , Matrix Metalloproteinase 14/metabolism , Neoplasm Invasiveness , Neoplastic Stem Cells/drug effects , Phenotype , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
12.
Mol Cancer Ther ; 15(3): 503-11, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26832794

ABSTRACT

Expression of TFAP2C in luminal breast cancer is associated with reduced survival and hormone resistance, partially explained through regulation of RET. TFAP2C also regulates EGFR in HER2 breast cancer. We sought to elucidate the regulation and functional role of EGFR in luminal breast cancer. We used gene knockdown (KD) and treatment with a tyrosine kinase inhibitor (TKI) in cell lines and primary cancer isolates to determine the role of RET and EGFR in regulation of p-ERK and tumorigenesis. KD of TFAP2C decreased expression of EGFR in a panel of luminal breast cancers, and chromatin immunoprecipitation sequencing (ChIP-seq) confirmed that TFAP2C targets the EGFR gene. Stable KD of TFAP2C significantly decreased cell proliferation and tumor growth, mediated in part through EGFR. While KD of RET or EGFR reduced proliferation (31% and 34%, P < 0.01), combined KD reduced proliferation greater than either alone (52% reduction, P < 0.01). The effect of the TKI vandetanib on proliferation and tumor growth response of MCF-7 cells was dependent upon expression of TFAP2C, and dual KD of RET and EGFR eliminated the effects of vandetanib. The response of primary luminal breast cancers to TKIs assessed by ERK activation established a correlation with expression of RET and EGFR. We conclude that TFAP2C regulates EGFR in luminal breast cancer. Response to vandetanib was mediated through the TFAP2C target genes EGFR and RET. Vandetanib may provide a therapeutic effect in luminal breast cancer, and RET and EGFR can serve as molecular markers for response.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , ErbB Receptors/genetics , Gene Expression Regulation, Neoplastic/drug effects , Piperidines/pharmacology , Quinazolines/pharmacology , Transcription Factor AP-2/metabolism , Animals , Biomarkers, Tumor , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Carcinogenesis/genetics , Carcinogenesis/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Disease Models, Animal , Female , Humans , MCF-7 Cells , Proto-Oncogene Proteins c-ret/genetics , Proto-Oncogene Proteins c-ret/metabolism , Transcription Factor AP-2/genetics , Tumor Burden/drug effects , Tumor Burden/genetics , Xenograft Model Antitumor Assays
13.
Ann Surg Oncol ; 22(13): 4287-94, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25971960

ABSTRACT

BACKGROUND: Preliminary data indicate that tyrosine kinase inhibitors (TKIs) function through rearranged during transfection (RET) in breast cancer. However, TKIs are not specific and can block several receptor tyrosine kinases (RTKs). This study used cell lines and primary breast cancer specimens to determine factors associated with TKI response. METHODS: Proliferation was assessed after short interfering RNA knockdown with or without sunitinib in breast cancer cell lines by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). Breast cancer tissue and matched normal breast was obtained from 30 women with invasive breast carcinoma. Gene expression was assessed by reverse transcriptase-polymerase chain reaction. Fresh tissue was treated in vitro with sunitinib or control media for 30 min, and response was assessed by phosphorylation-specific western blot. RESULTS: The RTKs including epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR1-3), platelet-derived growth factor receptor (PDGFRa/b), and Kit were overexpressed in triple-negative breast tumors relative to HER2- and estrogen receptor-alpha (ERα)-positive tumors and normal breast tissue. Knockdown of EGFR reduced in vitro proliferation in MCF-7 and MDA-MB-231 but not in SKBR-3 or ZR-75-1 breast cancer cells. With the exception of RET, response to sunitinib was independent of RTK expression in all four cell lines. Both ERα-positive and low-EGFR-expressing tumors had an increased in vitro sunitinib response, as determined by alteration of Erk activation. Expression of other RTKs and additional clinical factors were not associated with response. CONCLUSION: Triple-negative breast cancers overexpress RTKs but have decreased in vitro response to the TKI sunitinib. In addition to RET, TKIs that block EGFR may increase the therapeutic efficacy of TKIs in breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Drug Resistance, Neoplasm , ErbB Receptors/metabolism , Indoles/pharmacology , Protein Kinase Inhibitors/pharmacology , Pyrroles/pharmacology , Apoptosis/drug effects , Blotting, Western , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Proliferation/drug effects , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/genetics , Female , Humans , Middle Aged , Neoplasm Staging , Phosphorylation/drug effects , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects , Sunitinib , Tumor Cells, Cultured
14.
Ann Surg Oncol ; 22(3): 866-73, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25326397

ABSTRACT

BACKGROUND: Locally advanced breast cancer (LABC) poses complex management issues due to failure of response to chemotherapy and progression to local complications such as skin erosion, superinfection, and lymphedema. Most cell line and animal models are not adequate to study LABC. METHODS: A patient-derived xenograft (IOWA-1T) from a patient with LABC was characterized for expression profile, short tandem repeat profile, oncogenic mutations, xenograft growth, and response to therapy. RESULTS: Short tandem repeat profile authenticated the cell line as derived from a human woman. The primary tumor and derived xenografts were weakly estrogen receptor alpha positive (<5%), progesterone receptor negative, and HER2 nonamplified. Expression array profile compared to MCF-7 and BT-549 cell lines indicate that IOWA-1T was more closely related to basal breast cancer. IOWA-1T harbors a homozygous R248Q mutation of the TP53 gene; in vitro invasion assay was comparable to BT-549 and greater than MCF-7. IOWA-1T xenografts developed palpable tumors in 9.6 ± 1.6 days, compared to 49 ± 13 days for parallel experiments with BT-20 cells (p < 0.002). Tumor xenografts became locally advanced, growing to >2 cm in 21.6 ± 2 days, characterized by skin erosion necessitating euthanasia. The SUMO inhibitor anacardic acid inhibited the outgrowth of IOWA-1T xenografts, while doxorubicin had no effect on tumorigenesis. CONCLUSIONS: IOWA-1T is a novel cell line with an expression pattern consistent with basal breast cancer. Xenografts recapitulated LABC and provide a novel model for testing therapeutic drugs that may be effective in cases resistant to conventional chemotherapy.


Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Disease Models, Animal , Gene Expression Profiling , Animals , Biomarkers, Tumor/metabolism , Blotting, Western , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/metabolism , Cell Proliferation , Female , Flow Cytometry , Fluorescent Antibody Technique , Humans , Mice , Mice, Nude , Oligonucleotide Array Sequence Analysis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
15.
Cancer Res ; 75(1): 11-5, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25524900

ABSTRACT

Carcinoma cells can transition from an epithelial-to-mesenchymal differentiation state through a process known as epithelial-mesenchymal transition (EMT). The process of EMT is characterized by alterations in the pattern of gene expression and is associated with a loss of cell polarity, an increase in invasiveness, and an increase in cells expressing cancer stem cell (CSC) markers. The reverse process of mesenchymal-to-epithelial transition (MET) can also occur, though the transitions characterizing EMT and MET can be incomplete. A growing number of transcription factors have been identified that influence the EMT/MET processes. Interestingly, SUMOylation regulates the functional activity of many of the transcription factors governing transitions between epithelial and mesenchymal states. In some cases, the transcription factor is a small ubiquitin-like modifier conjugated directly, thus altering its transcriptional activity or cell trafficking. In other cases, SUMOylation alters transcriptional mechanisms through secondary effects. This review explores the role of SUMOylation in controlling transcriptional mechanisms that regulate EMT/MET in cancer. Developing new drugs that specifically target SUMOylation offers a novel therapeutic approach to block tumor growth and metastasis.


Subject(s)
Epithelial-Mesenchymal Transition/physiology , Neoplasms/metabolism , Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Sumoylation , Transcription Factors/metabolism , Humans
16.
J Surg Oncol ; 110(3): 291-7, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24850538

ABSTRACT

Positive peritoneal cytology (Cyt+) is an important staging tool for patients with locally advanced gastric cancer. The objective of this review is to evaluate the current literature regarding cytology evaluation in patients with gastric cancer and to provide recommendations on the inclusion of this powerful prognosticator in patients with this disease. A literature search was performed for recent and pertinent studies evaluating peritoneal cytology in patients with gastric adenocarcinoma. Peritoneal cytology as the only evidence for M1 disease is present in up to 10% of patients with locally advanced gastric cancer; survival in the setting of Cyt+ is dismal when gastrectomy is the first line of therapy. Improved survival is associated with response to chemotherapy indicated by conversion to negative cytology, good performance status, and antral tumors. Highly select patients with Cyt+ treated with gastrectomy show improved survival in only some of the available studies. There are high quality studies that support the routine practice of peritoneal cytology evaluation in patients with locally advanced gastric cancer. The role of gastrectomy remains unclear in patients with Cyt+ and clinical trials are needed to define the best treatment option for this select group of patients.


Subject(s)
Adenocarcinoma/pathology , Neoplasm Staging , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/therapy , Peritoneum/pathology , Stomach Neoplasms/pathology , Adenocarcinoma/mortality , Adenocarcinoma/secondary , Adenocarcinoma/therapy , Chemotherapy, Cancer, Regional Perfusion , Combined Modality Therapy , Gastrectomy , Humans , Hyperthermia, Induced , Laparoscopy , Lymphatic Metastasis , Peritoneal Lavage , Peritoneal Neoplasms/diagnosis , Prognosis , Stomach Neoplasms/mortality , Stomach Neoplasms/therapy
17.
Clin Cancer Res ; 20(8): 2115-25, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24526731

ABSTRACT

PURPOSE: Recent findings suggest that combination treatment with antiestrogen and anti-RET may offer a novel treatment strategy in a subset of patients with breast cancer. We investigated the role of RET in potentiating the effects of antiestrogen response and examined whether RET expression predicted the ability for tyrosine kinase inhibitor (TKI) to affect extracellular signal-regulated kinase 1/2 (ERK1/2) activation in primary breast cancer. EXPERIMENTAL DESIGN: Growth response, ERK1/2 activation, Ki-67, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling were assessed in breast cancer cell lines in vitro and in xenografts with vandetanib and/or tamoxifen. Thirty tumors with matched normal breast tissue were evaluated for RET expression and response to TKI treatment. RESULTS: Vandetanib potentiated the inhibitory effect of tamoxifen in hormone responsive (P = 0.01) and hormone insensitive (P < 0.001) estrogen receptor α (ERα)-positive breast cancer cells. Vandetanib significantly repressed tumorigenesis of MCF-7 xenografts (P < 0.001), which displayed decreased activation of ERK1/2 and AKT. Vandetanib and tamoxifen reduced the growth of established tumors with a greater effect of dual therapy compared with single agent (P = 0.003), with tamoxifen-reducing proliferative index and vandetanib-inducing apoptosis. In primary breast cancers, RET expression correlated with the ERα-positive subtype. Relative decrease in ERK1/2 phosphorylation with TKI treatment was 42% (P < 0.001) in RET-positive tumors versus 14% (P = ns) in RET-negative tumors. CONCLUSIONS: Vandetanib potentiated the antigrowth effects of tamoxifen in breast cancer, which was mediated through RET activation. RET predicted response to TKI therapy with minimal effects on ERK1/2 activation in RET-negative tumors. The preclinical data support evaluation of antiestrogen in combination with TKI as a potential treatment strategy for RET-positive luminal breast cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Estrogen Receptor Modulators/pharmacology , Piperidines/pharmacology , Proto-Oncogene Proteins c-ret/antagonists & inhibitors , Quinazolines/pharmacology , Animals , Apoptosis/drug effects , Blotting, Western , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Synergism , Estrogen Receptor Modulators/administration & dosage , Estrogen Receptor alpha/metabolism , Female , Humans , MCF-7 Cells , Mice, Nude , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Piperidines/administration & dosage , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-ret/genetics , Proto-Oncogene Proteins c-ret/metabolism , Quinazolines/administration & dosage , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects , Signal Transduction/genetics , Tamoxifen/administration & dosage , Xenograft Model Antitumor Assays
18.
Mol Cell Oncol ; 1(3): e964624, 2014.
Article in English | MEDLINE | ID: mdl-27308355

ABSTRACT

Cancer stem cells (CSCs) represent a subset of tumor cells with tumor-initiating potential. We recently demonstrated that inhibition of the sumoylation pathway cleared the CSC population and repressed the outgrowth of basal breast cancer xenografts. Targeting the sumoylation pathway offers a novel treatment strategy for basal breast cancer.

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