Clinical effectiveness of microporous polysaccharide hemospheres in mastectomy for patients with breast cancer

Background

Microporous polysaccharide hemospheres (MPH) are hydrophilic particles administered to reduce the incidence of seroma after mastectomy, but their clinical effectiveness remains controversial. Because a previous randomized, controlled study in a small cohort could not demonstrate the effectiveness of MPH in breast surgery, we evaluated their effectiveness in surgery for breast cancer in a larger cohort.

Methods

Medical records of 352 patients who underwent total mastectomy for breast cancer were retrospectively reviewed. Clinical data were compared between 126 patients who received MPH during surgery (MPH group) and 226 who did not (control group) according to surgical procedures. Patients were significantly older in the MPH group than in the control group because of selection bias, but other factors, such as body mass index and number of dissected lymph nodes, did not differ between groups.

Results

When analyzed by use of axillary manipulation, the drain placement period and drainage volume were significantly less in the MPH group than in the control group for patients with mastectomy and sentinel lymph node biopsy. Only drainage volume was significantly less in the MPH group for patients with mastectomy and axillary lymph node dissection. The frequency of total postoperative complications, such as seroma requiring puncture, did not differ between groups.

Conclusions

Use of MPH may decrease the postoperative drainage volume and drain placement period in mastectomy for patients with breast cancer.

Application of Machine Learning Analyses Using Clinical and [18F]-FDG-PET/CT Radiomic Characteristics to Predict Recurrence in Patients with Breast Cancer

PURPOSE

To develop and identify machine learning (ML) models using pretreatment clinical and 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography ([18F]-FDG-PET)-based radiomic characteristics to predict disease recurrences in patients with breast cancers who underwent surgery.

PROCEDURES

This retrospective study included 112 patients with 118 breast cancer lesions who underwent [18F]-FDG-PET/ X-ray computed tomography (CT) preoperatively, and these lesions were assigned to training (n=95) and testing (n=23) cohorts. A total of 12 clinical and 40 [18F]-FDG-PET-based radiomic characteristics were used to predict recurrences using 7 different ML algorithms, namely, decision tree, random forest (RF), neural network, k-nearest neighbors, naive Bayes, logistic regression, and support vector machine (SVM) with a 10-fold cross-validation and synthetic minority over-sampling technique. Three different ML models were created using clinical characteristics (clinical ML models), radiomic characteristics (radiomic ML models), and both clinical and radiomic characteristics (combined ML models). Each ML model was constructed using the top ten characteristics ranked by the decrease in Gini impurity. The areas under ROC curves (AUCs) and accuracies were used to compare predictive performances.

RESULTS

In training cohorts, all 7 ML algorithms except for logistic regression algorithm in the radiomics ML model (AUC = 0.760) achieved AUC values of >0.80 for predicting recurrences with clinical (range, 0.892-0.999), radiomic (range, 0.809-0.984), and combined (range, 0.897-0.999) ML models. In testing cohorts, the RF algorithm of combined ML model achieved the highest AUC and accuracy (95.7% (22/23)) with similar classification performance between training and testing cohorts (AUC: training cohort, 0.999; testing cohort, 0.992). The important characteristics for modeling process of this RF algorithm were radiomic GLZLM_ZLNU and AJCC stage.

CONCLUSIONS

ML analyses using both clinical and [18F]-FDG-PET-based radiomic characteristics may be useful for predicting recurrence in patients with breast cancers who underwent surgery.

Relationship between Delayed Breast Cancer Diagnosis and Behavioral Economic Factors and Personality Characteristics

BACKGROUND

Delays in breast cancer diagnosis can allow the disease to progress to an incurable stage. However, factors that cause patients to delay seeking treatment are unclear. In this study, we aimed to identify behavioral economic factors and personality characteristics of patients with breast cancer who had a delayed diagnosis.

METHODS

We analyzed questionnaires completed by 41 patients with breast cancer. A delayed diagnosis was defined if the time between the first symptom and the medical visit was more than 6 months.

RESULTS

We found 11 patients who had a delayed diagnosis. The significant characteristics associated with patients with breast cancer who had delayed diagnosis were: (i) less experience with breast cancer screening; (ii) progressive disease stage; and (iii) low time and future time preference. We found no significant behavioral economic factors other than time preference, and personality that differed between patients with breast cancer who did and did not have a delayed diagnosis.

CONCLUSION

Low time preference rate is a characteristic of patients with breast cancer who had a delayed diagnosis.

Oncogenic Targets Regulated by Tumor-Suppressive miR-30c-1-3p and miR-30c-2-3p: TRIP13 Facilitates Cancer Cell Aggressiveness in Breast Cancer

Accumulating evidence suggests that the miR-30 family act as critical players (tumor-suppressor or oncogenic) in a wide range of human cancers. Analysis of microRNA (miRNA) expression signatures and The Cancer Genome Atlas (TCGA) database revealed that that two passenger strand miRNAs, miR-30c-1-3p and miR-30c-2-3p, were downregulated in cancer tissues, and their low expression was closely associated with worse prognosis in patients with BrCa. Functional assays showed that miR-30c-1-3p and miR-30c-2-3p overexpression significantly inhibited cancer cell aggressiveness, suggesting these two miRNAs acted as tumor-suppressors in BrCa cells. Notably, involvement of passenger strands of miRNAs is a new concept of cancer research. Further analyses showed that seven genes (TRIP13, CCNB1, RAD51, PSPH, CENPN, KPNA2, and MXRA5) were putative targets of miR-30c-1-3p and miR-30c-2-3p in BrCa cells. Expression of seven genes were upregulated in BrCa tissues and predicted a worse prognosis of the patients. Among these genes, we focused on TRIP13 and investigated the functional significance of this gene in BrCa cells. Luciferase reporter assays showed that TRIP13 was directly regulated by these two miRNAs. TRIP13 knockdown using siRNA attenuated BrCa cell aggressiveness. Inactivation of TRIP13 using a specific inhibitor prevented the malignant transformation of BrCa cells. Exploring the molecular networks controlled by miRNAs, including passenger strands, will facilitate the identification of diagnostic markers and therapeutic target molecules in BrCa.

Implications of PD-1, Tim-3, and TIGIT Expression for Cancer Immunity and Pancreatic Cancer Prognosis

BACKGROUND/AIM

The development and application of cancer immunotherapy to pancreatic cancer has not progressed because its efficacy has not been proven in clinical trials. In this study, we aimed to explore potential targets of immune checkpoint inhibitor therapy for pancreatic cancer treatment.

MATERIALS AND METHODS

We collected resected specimens from 40 patients with pancreatic cancer who underwent resection at our Institution without any preoperative treatment. We evaluated the expression of molecules in the programmed death receptor-1 (PD-1), T cell immunoglobulin mucin-3 (Tim-3)/Galectin-9, and CD155/T cell immunoreceptor with Ig and ITIM domains (TIGIT) pathways using immunohistochemical staining. The correlation between the expression pattern of these molecules and patient prognosis were assessed using Kaplan-Meier analysis.

RESULTS

An increased number of CD8+ T cells in pancreatic cancer tissue was significantly associated with a better patient prognosis. Additionally, patients with a higher ratio of PD-1 expression to CD8+ T cells had a worse prognosis. We observed no correlation between the Tim-3/Galectin-9 and CD155/TIGIT pathways and patient prognosis.

CONCLUSION

Modifications in the immune environment to increase T cell infiltration into tumors could result in the PD-1 pathway becoming a potential target to treat pancreatic cancer using immune checkpoint inhibition.

Cathepsin G-induced malignant progression of MCF-7 cells involves suppression of PAF signaling through induced expression of PAFAH1B2

Breast cancer is primarily classified into ductal and lobular types, as well as into noninvasive and invasive cancer. Invasive cancer involves lymphatic and hematogenous metastasis. In breast cancer patients with distant metastases, a neutrophil-derived serine protease; cathepsin G (Cat G), is highly expressed in breast cancer cells. Cat G induces cell migration and multicellular aggregation of MCF-7 human breast cancer cells; however, the mechanism is not clear. Recently, platelet-activating factor (PAF)-acetylhydrolase (PAF-AH), the enzyme responsible for PAF degradation, was reported to be overexpressed in some tumor types, including pancreatic and breast cancers. In this study, we investigated whether PAF-AH is involved in Cat G-induced aggregation and migration of MCF-7 cells. We first showed that Cat G increased PAF-AH activity and elevated PAFAH1B2 expression in MCF-7 cells. The elevated expression of PAFAH1B2 was also observed in human breast cancer tissue specimens by immunohistochemical analysis. Furthermore, knockdown of PAFAH1B2 in MCF-7 cells suppressed the cell migration and aggregation induced by low concentrations, but not high concentrations, of Cat G. Carbamoyl PAF (cPAF), a nonhydrolyzable PAF analog, completely suppressed Cat G-induced migration of MCF-7 cells. In addition, PAF receptor (PAFR) inhibition induced cell migration of MCF-7 cells even in the absence of Cat G, suggesting that Cat G suppresses the activation of PAFR through enhanced PAF degradation due to elevated expression of PAFAH1B2 and thereby induces malignant phenotypes in MCF-7 cells. Our findings may lead to a novel therapeutic modality for treating breast cancer by modulating the activity of Cat G/PAF signaling.

Metastasis of breast cancer to the right kidney with a tumor thrombus in the inferior vena cava: a case report

Background

It is quite rare for breast cancer to metastasize to the kidney with a tumor thrombus in the inferior vena cava.

Case presentation

A Japanese woman in her forties was diagnosed with cancer of the left breast and underwent left mastectomy with sentinel lymph node biopsy. The final pathological diagnosis was pT1aN0M0, stage IA (ER positive, PgR positive, HER2 negative). Thirteen years later, she presented for care with the complaint of abdominal pain. By imaging findings, right renal carcinoma with a tumor thrombus in the inferior vena cava and lung metastases was suspected. However, her tumors were refractory to molecular targeted therapy. In addition, CT-guided needle biopsy of the kidney and lung lesions was done and it was revealed that lesions of the left lung and the right kidney was breast cancer metastases (ER positive, PgR positive, HER2 negative). The patient started combination therapy consisting of abemaciclib, tamoxifen and leuprorelin. Six months later, she died from progression of her metastatic disease.

Conclusions

It is sometimes difficult to differentiate between primary renal cancer and kidney metastases from breast cancer on imaging. Renal biopsy is recommended before commencing treatment.

Accessory breast cancer in the inframammary region: a case report and review of the literature

BACKGROUND

Although a few cases of accessory breast cancer (ABC) have been reported, most were in the axillary region. We encountered an extremely rare case of ABC in the inframammary region (IMR).

CASE PRESENTATION

The patient was a 68-year-old postmenopausal woman who had noticed a congenital accessory nipple in her left IMR with slight, occasional discharge 20 years ago. Recently, she noticed a mass under the accessory nipple and visited a nearby clinic; fine-needle aspiration cytology of the mass revealed that it was malignant. She presented to our department 2 weeks after she had noticed the mass. Physical and imaging examinations showed an irregular tumor mass 1.7 × 1.4 × 1.0 cm in size connected to the accessory nipple beneath the left normal breast. Neither distant metastasis nor lymph node swelling was observed. Ultrasound-guided core needle biopsy revealed the mass to be invasive ductal carcinoma. We diagnosed her tumor as ABC in the left IMR; cT1cN0M0: stage IA. Curative wide resection with sentinel node biopsy was performed. Intraoperative evaluation of the frozen section revealed a hot and green ipsilateral axillary lymph node that was free from carcinoma; therefore, nodal dissection was avoided. Histopathological examination including immunochemical staining revealed that the tumor was invasive ductal carcinoma arising from the accessory breast tissue, scirrhous type, 1.7 × 1.4 × 1.0 cm in size, with a solid intraductal component. There was no lymphovascular infiltration, and the surgical margin was 1.5 cm or more. The tumor was estrogen and progesterone receptor-positive, Her2/neu-negative, and had a Ki-67 labeling index of 20%. There was no involvement of the three hot and/or green nodes. The final classification was pT1cN0(sn)M0: stage IA. Letrozole 2.5 mg/day will be administered for 5 years as adjuvant hormonal therapy.

CONCLUSIONS

A cutaneous and/or subcutaneous lesion except for proper breast tissue on the milk line, or mammary ridge from axilla to groin may be an accessory breast tissue. Its serial abnormalities must be worried malignant potential to ductal carcinoma which needs some imaging and pathological examinations for definitive diagnosis and appropriate treatment according to the usual orthotopic breast cancer without delay.

Immediate breast reconstruction with expander following recurrent lesion resection and exchange to silicon breast implant in a pregnant triple negative breast cancer patient: case report

A 39-year-old gravida 1 para 1 pregnant Japanese woman underwent skin-sparing mastectomy and axillary lymph node dissection with immediate breast reconstruction (IBR) using a tissue expander (TE) at 32 weeks of pregnancy under general anesthesia. Inserted TE (300 cc) was expanded during breast feeding while the volume was 240 cc of the resected breast tissue. One month after delivery, 2 months after surgery, the contralateral healthy breast increased in size and the inframammary line was deviated toward a caudal site which was larger than 300 cc-inflated TE. She stopped breast feeding to receive a systemic chemotherapy after one months-breast feeding. At 3 months after delivery, the healthy breast size was smaller than the 250 cc-expanded breast and both the inframammary lines were at the same level. She was diagnosed local recurrence 3 month-postoperatively, so we resected the recurrent lesion and exchanged TE to silicon breast implant immediately. Finally, a good symmetry was obtained after insertion of the 220 cc SBI. At an IBR using TE, we should know the dynamic change of breast volume and the level of inframammary line of the healthy breast during those phases of pregnancy, delivery, and nursing.

Molecular pathogenesis of breast cancer: impact of miR-99a-5p and miR-99a-3p regulation on oncogenic genes

Our recent research has revealed that passenger strands of certain microRNAs (miRNAs) function as tumor-suppressive miRNAs in cancer cells, e.g., miR-101-5p, miR-143-5p, miR-144-5p, miR-145-3p, and miR-150-3p. Thus, they are important in cancer pathogenesis. Analysis of the miRNA expression signature of breast cancer (BrCa) showed that the expression levels of two miRNAs derived from pre-miR-99a (miR-99a-5p and miR-99a-3p) were suppressed in cancerous tissues. The aim of this study was to identify oncogenic genes controlled by pre-miR-99a that are closely involved in the molecular pathogenesis of BrCa. A total of 113 genes were identified as targets of pre-miR-99a regulation (19 genes modulated by miR-99a-5p, and 95 genes regulated by miR-99a-3p) in BrCa cells. Notably, FAM64A was targeted by both of the miRNAs. Among these targets, high expression of 16 genes (C5orf22, YOD1, SLBP, F11R, C12orf49, SRPK1, ZNF250, ZNF695, CDK1, DNMT3B, TRIM25, MCM4, CDKN3, PRPS, FAM64A, and DESI2) significantly predicted reduced survival of BrCa patients based upon The Cancer Genome Atlas (TCGA) database. In this study, we focused on FAM64A and investigated the relationship between FAM64A expression and molecular pathogenesis of BrCa subtypes. The upregulation of FAM64A was confirmed in BrCa clinical specimens. Importantly, the expression of FAM64A significantly differed between patients with Luminal-A and Luminal-B subtypes. Our data strongly suggest that the aberrant expression of FAM64A is involved in the malignant transformation of BrCa. Our miRNA-based approaches (identification of tumor-suppressive miRNAs and their controlled targets) will provide novel information regarding the molecular pathogenesis of BrCa.

Surgical Resection With Pedicled Rotation Flap for Post-mastectomy Locoregional Breast Cancer Recurrence

BACKGROUND/AIM

Locoregional recurrence (LRR) of breast cancer is reported to occur at a rate of 5%-15%. Wide excision of LRR is the recommended treatment, which can increase the probability of subsequent local control. Herein, we describe a surgical technique wherein a pedicled skin and subcutaneous flap close the skin defect after resection of a breast cancer LRR without use of a skin graft.

PATIENTS AND METHODS

We reviewed four patients who underwent surgical resection using a pedicled rotation flap for chest wall recurrence after mastectomy.

RESULTS

The surgical margin was set 2 cm apart from the tumor margin. After resection of tumor from the chest wall, we formed an adjacent pedicled flap and rotated the flap to the skin defect. There were no post-operative complications, including wound necrosis.

CONCLUSION

Surgical resection with a pedicled rotation flap for post-mastectomy breast cancer LRR is a highly feasible way to achieve complete resection.

The usefulness and utilization of a detachable steel wire-rimmed retractor (KN retractor) for endoscopic thyroid and parathyroid surgery

PURPOSE

In endoscopic surgery, surgeons occasionally encounter difficulties due to visual field obstruction by muscles or blood vessels. In these situations, specialized instruments that can effectively retract these obstructions are required. Recently, we developed a new detachable wire-rimmed retractor (KN retractor) for narrow-space surgery.

METHODS

We evaluated the utility of this KN retractor in 15 patients with thyroid and parathyroid disease. Of those, five patients with papillary thyroid cancer had gasless endoscopic hemithyroidectomy with central node dissection, five underwent endoscopic total thyroidectomy for Graves' disease, and the remaining five received endoscopic parathyroidectomy with gas insufflation.

RESULTS

Surgeons were able to perform meticulous operations in a satisfactory visual field supported by the KN retractor. In all patients, the strap muscles were preserved without cutting. The average operating time was 149, 154, and 81 min in patients who underwent hemithyroidectomy with central node dissection, total thyroidectomy, and parathyroidectomy, respectively. Gas insufflation was successfully completed in all cases while maintaining sufficient airtightness.

CONCLUSIONS

The KN retractor is suitable for both the gasless lifting method and gas insufflation surgery in a narrow space. We believe that the KN retractor is a new device that will greatly improve the safety and shorten the operation time in endoscopic surgery.

Breast cancer with an intraductal component that was proven genetically to be metastasis of contralateral breast cancer: a case report

Background

When diagnosing patients with bilateral breast cancer, it is challenging to determine the relationship between multiple breast cancer lesions at the individual patient level with certainty.

Case presentation

A 35-year-old Japanese woman was diagnosed with a left breast cancer. She was previously diagnosed with right pT3N3M0 stage IIIC breast cancer and underwent chemotherapy with targeted therapy, radiotherapy, and endocrine therapy as adjuvant treatment after mastectomy and axillary lymph node dissection. Approximately 2 years after the first surgery, her left breast cancer was preoperatively diagnosed as a contralateral primary breast cancer, and left mastectomy and axillary lymph node dissection were performed. Histopathologically, the tumor was determined to be invasive ductal carcinoma accompanied with several intraductal components. After a second surgery, mutation analysis of her bilateral breast cancer was performed in a clinical study, which revealed that her metachronous bilateral breast tumors had the same GATA3 and CSMD1 mutations. Thus, mutation analysis strongly supported her latter left breast cancer being a metastatic lesion from the former right breast cancer. Some difficulties in diagnosing bilateral breast cancer exist when determining whether they are double primary cancers or represent contralateral breast metastasis. The existence of intraductal components is a critical piece of information for suspecting primary lesions. However, this case demonstrated that metastatic contralateral breast lesions can have intraductal components.

Conclusion

Herein we report a genetically proven contralateral breast metastasis with some intraductal components.

Oncoplastic breast surgery combining partial mastectomy with a triangular skin resection and re-centralization of the nipple-areola

The treatment of early breast cancer using breast conservation therapy (BCT) commonly ensures local control and acceptable cosmetic results. We herein report a useful technique to obtain symmetry of the breast shape and a level inframammary line and nipple-areola, which achieved excellent results. Six Japanese patients with early breast cancer located on the upper area of the breast were enrolled into this study. A triangle-shaped area of skin was removed together with cancerous and healthy-surrounding breast tissue. Two crescents were designed and de-epithelialized in the directions of 9 o'clock and 3 o'clock. The width of the crescent was decided to be the same as a half or the length of the base of a triangle to be removed. After partial mastectomy, the inner and outer glandular flaps were horizontally sutured. The operations were simple to perform and were not associated with any postoperative complications. Oncoplastic breast surgery combining partial mastectomy with triangular skin resection and re-centralization of the nipple-areola was useful for patients with breast cancer on the upper quadrant area of non-ptotic breasts.

Lung recurrence and its therapeutic strategy in patients with pancreatic cancer

BACKGROUND

/Objectives: The lung is a major metastatic site of pancreatic cancer (PC). We aimed to assess the features and prognosis of patients with PC according to the recurrence pattern and the effect of resection of recurrent lung lesion.

METHODS

We enrolled 168 PC patients who had undergone macroscopically curative resection. All resected lung tumors were evaluated immunohistochemically for expressions of thyroid transcription factor-1 (TTF-1) and napsin A.

RESULTS

The most common site of first recurrence was the liver and local site, followed by the lung, peritoneum, and lymph node. Lung recurrence was observed significantly later than was liver recurrence. The median survival time (MST) after recurrence in patients with first recurrence in the lung was significantly longer than MST in patients with first recurrence in the liver (15.2 months vs 5.2 months, p = 0.039). Seven patients with lung recurrence underwent resection of the recurrent lesion. Surgical resection of single metastasis limited to the lung showed favorable overall survival after recurrence (MST = 36.5 months). Patients with single metastasis limited to the lung showed significantly lower value of FDG-PET SUV_max of the primary pancreatic tumor.

CONCLUSIONS

Patients with first recurrence in the lung showed better prognosis than did patients with first recurrence in the liver. Single metastasis limited to the lung could benefit from surgical resection and was significantly associated with lower FDG-PET SUV_max of the primary pancreatic tumor.

RNA-sequence-based microRNA expression signature in breast cancer: tumor-suppressive miR-101-5p regulates molecular pathogenesis

Aberrantly expressed microRNA (miRNA) are known to disrupt intracellular RNA networks in cancer cells. Exploring miRNA‐dependent molecular networks is a major challenge in cancer research. In this study, we performed RNA‐sequencing of breast cancer (BrCa) clinical specimens to identify tumor‐suppressive miRNA in BrCa. In total, 64 miRNA were identified as candidate tumor‐suppressive miRNA in BrCa cells. Analysis of our BrCa signature revealed that several miRNA duplexes (guide strand/passenger strand) derived from pre‐miRNA were downregulated in BrCa tissues (e.g. miR‐99a‐5p/‐3p, miR‐101‐5p/‐3p, miR‐126‐5p/‐3p, miR‐143‐5p/‐3p, and miR‐144‐5p/‐3p). Among these miRNA, we focused on miR‐101‐5p, the passenger strand of pre‐miR‐101, and investigated its tumor‐suppressive roles and oncogenic targets in BrCa cells. Low expression of miR‐101‐5p predicted poor prognosis in patients with BrCa (overall survival rate: P = 0.0316). Ectopic expression of miR‐101‐5p attenuated aggressive phenotypes, e.g. proliferation, migration, and invasion, in BrCa cells. Finally, we identified seven putative oncogenic genes (i.e. High Mobility Group Box 3, Epithelial splicing regulatory protein 1, GINS complex subunit 1 (GINS1), Tumor Protein D52, Serine/Arginine‐Rich Splicing Factor Kinase 1, Vang‐like protein 1, and Mago Homolog B) regulated by miR‐101‐5p in BrCa cells. The expression of these target genes was associated with the molecular pathogenesis of BrCa. Furthermore, we explored the oncogenic roles of GINS1, whose function had not been previously elucidated, in BrCa cells. Aberrant expression of GINS1 mRNA and protein was observed in BrCa clinical specimens, and high GINS1 expression significantly predicted poor prognosis in patients with BrCa (overall survival rate: P = 0.0126). Knockdown of GINS1 inhibited the malignant features of BrCa cells. Thus, identification of tumor‐suppressive miRNA and molecular networks controlled by these miRNA in BrCa cells may be an effective strategy for elucidation of the molecular pathogenesis of this disease.

Upgraded bidirectional approach video-assisted neck surgery (BAVANS) using a rigid endoscope with variable viewing direction for advanced endoscopic lymph node dissection in thyroid cancer patients

In 2011, we developed bidirectional approach video-assisted neck surgery (BAVANS) for endoscopic thyroid cancer surgery. BAVANS combines two different approach pathways at 180 degrees to the cervical lesion for endoscopic thyroidectomy and complete cervical lymphadenectomy. We reported previously that the cranio-caudal approach is extremely useful for endoscopic complete lymph node dissection around the trachea. In 2014, we upgraded the initial BAVANS for better maneuverability and quality of lymph node dissection. A new high-tech rigid endoscope with a variable viewing direction (EndoCAMeleon™), has enabled us to reduce the camera port in the anterior neck while keeping the easy maneuverability and the same quality of central lymph node dissection (LND) as with the initial BAVANS. Endoscopic thyroid cancer surgery is now evolving concurrently with new visual technology.

Clinical Features of Breast Cancer Patients with Human T-Cell Lymphotropic Virus Type-1 Infection

Background: Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes adult T-cell leukemia/lymphoma (ATL), an aggressive form of T-cell malignancy. The relationship between HTLV-1 infection and cancer progression is controversial. HTLV-1 encodes oncogenic protein TAX1 and it is hypothesized that HTLV-1 infection is associated with breast cancer progression. In this study, we evaluated the relationship between HTLV-1 infection and clinicopathological factors in breast cancer patients. Methods: We retrospectively analyzed 610 patients with primary breast cancer who underwent surgical treatment without preoperative chemotherapy at Kagoshima University Hospital between January 2001 and January 2015. Results: When patients with and without HTLV-1 infection were compared, no differences in clinicopathological factors were observed, except for age. Disease-free survival and overall survival rates did not differ between groups. Conclusions: HTLV-1–positive patients were significantly older than HTLV-1–negative patients. It was supposed to be due to the fact that the HTLV-1 infection rate is decreasing. Any effect of HTLV-1 infection on breast cancer progression appears to be negligibly small.

Apocrine papillary lesion: comparison of pathological findings from 22 years previously and the present

Apocrine papillary lesion (APL) is difficult to diagnose as benign or malignant. We experienced an APL remaining in the body for 22 years. We present a case of a 71-year-old woman who had undergone excisional biopsy 22 years previously at the first hospital that she visited. 1 year previously, she had undergone fine-needle aspiration cytology at a second hospital, and the lesion was diagnosed as potentially malignant. She underwent core-needle biopsy at a third hospital, but whether the lesion was benign or malignant could not be definitively diagnosed. We performed right mastectomy and sentinel lymph-node biopsy, because her tumor was suspected to be malignant based on imaging means, and malignancy could not be ruled out on either biopsy or cytology. The histopathological diagnosis was tiny foci of apocrine proliferative lesion with massive hemorrhagic necrosis and no tumor metastasis in two sentinel lymph nodes. Retrospectively, we compared all of the patient's previous specimens with the present ones, and applied the recent pathological diagnostic criteria. Although the biopsy specimen excised 22 years ago suggested an encapsulated apocrine papillary carcinoma or a papilloma with apocrine ductal carcinoma in situ, neither infiltration nor metastasis has occurred. Furthermore, neither the pathological findings nor the clinical behavior has changed over time.

Two cases of radiation-associated angiosarcoma of the breast

Background

The incidence of radiation-associated angiosarcoma (RAA) of the breast has been increasing, and its prognosis is reportedly poor. It is important to remove tumor tissues completely to prevent recurrence.

Case presentation

We report two cases of patients with RAA of the breast. Both patients had a nodule in their remaining breast a few years after undergoing breast-conserving surgery and radiation therapy for breast cancer. The nodules were diagnosed as angiosarcoma by skin biopsy and open biopsy, respectively. To determine the extent of lesion spread, mapping biopsy was performed before surgery. Both patients underwent mastectomy, extensive skin resection, and split skin grafting. Pathological findings showed that their tumors could be completely resected. After surgery, chemotherapy was performed.

Conclusion

In our cases, no local or distant recurrence has been detected in either patient for over 4 years. We identified the range of tumor invasion by preoperative mapping biopsy and completely resected all tumor tissue.

Three-Dimensional Organoids Reveal Therapy Resistance of Esophageal and Oropharyngeal Squamous Cell Carcinoma Cells

BACKGROUND & AIMS

Oropharyngeal and esophageal squamous cell carcinomas, especially the latter, are a lethal disease, featuring intratumoral cancer cell heterogeneity and therapy resistance. To facilitate cancer therapy in personalized medicine, three-dimensional (3D) organoids may be useful for functional characterization of cancer cells ex vivo. We investigated the feasibility and the utility of patient-derived 3D organoids of esophageal and oropharyngeal squamous cell carcinomas.

METHODS

We generated 3D organoids from paired biopsies representing tumors and adjacent normal mucosa from therapy-naïve patients and cell lines. We evaluated growth and structures of 3D organoids treated with 5-fluorouracil ex vivo.

RESULTS

Tumor-derived 3D organoids were grown successfully from 15 out of 21 patients (71.4%) and passaged with recapitulation of the histopathology of the original tumors. Successful formation of tumor-derived 3D organoids was associated significantly with poor response to presurgical neoadjuvant chemotherapy or chemoradiation therapy in informative patients (P = 0.0357, progressive and stable diseases, n = 10 vs. partial response, n = 6). The 3D organoid formation capability and 5-fluorouracil resistance were accounted for by cancer cells with high CD44 expression and autophagy, respectively. Such cancer cells were found to be enriched in patient-derived 3D organoids surviving 5-fluorouracil treatment.

CONCLUSIONS

The single cell-based 3D organoid system may serve as a highly efficient platform to explore cancer therapeutics and therapy resistance mechanisms in conjunction with morphological and functional assays with implications for translation in personalized medicine.

Clinicopathological characteristics of disseminated carcinomatosis of the bone marrow in breast cancer patients

Disseminated carcinomatosis of the bone marrow (DCBM) is characterized by diffuse infiltrative growth of tumor cells in the bone marrow and is associated with systemic hematological disorders. Bone marrow metastases from breast cancer are not rare, and they may lead to serious life-threatening conditions when there is an associated hematological disorder. Therefore, DCBM necessitates a definitive diagnosis and prompt systemic therapy. We herein present 4 such cases and a review of the previous relevant literature. Bone marrow biopsy is an effective method for diagnosing DCBM, and it may also be useful for selecting the optimal therapy. The malignant cells in the bone marrow biopsy specimens from all 4 patients were negative for progesterone receptor expression, and in 1 case, human epidermal growth factor receptor 2/neu expression was discordant between the primary tumor and the bone marrow metastases. Patients with DCBM often require granulocyte colony-stimulating factor and/or blood transfusions due to a DCBM-related hematological disorder. Although systemic chemotherapy for DCBM may temporarily exacerbate the need for hematological support, systemic chemotherapy may be effective for DCBM in breast cancer patients. In our experience, endocrine therapy has also been proven effective for DCBM. The aim of the present study was to review the clinical characteristics and the treatments used in 4 breast cancer patients with DCBM.

Correction: Integrated Multiregional Analysis Proposing a New Model of Colorectal Cancer Evolution

[This corrects the article DOI: 10.1371/journal.pgen.1005778.].

Bidirectional Approach of Video-Assisted Neck Surgery (BAVANS): Endoscopic complete central node dissection with craniocaudal view for treatment of thyroid cancer

INTRODUCTION

Endoscopic thyroidectomy is a well-established surgical technique that is mainly performed for benign thyroid disease. We considered that endoscopic surgery could also be widely indicated for the treatment of thyroid cancer. We herein describe our new bidirectional approach of video-assisted neck surgery (BAVANS) for complete central node dissection in endoscopic thyroid cancer surgery.

METHODS

BAVANS involves two different directional pathways to the cervical lesion. Before lymph node dissection, we perform endoscopic thyroidectomy via a conventional gasless precordial or axillary approach. After thyroidectomy, the surgeon repositions by the head of the patient and inserts three ports in front of the upper neck lesion in the submandibular area to approach the paratracheal lesion from an overhead-to-caudal direction.

RESULTS

BAVANS allows for an excellent craniocaudal view and easy access to the peritracheal lymph nodes. Sixteen patients with papillary thyroid cancer underwent BAVANS and progressed satisfactorily after surgery. Of those patients, eight underwent total or near total thyroidectomy, and five patients underwent bilateral central node dissection. The average number of retrieved lymph nodes with unilateral central node dissection was nine, which was higher than that achieved with conventional open surgery. All patients began oral intake within 5 h after surgery. Postoperative Horner syndrome occurred in one patient. No other complications were noted.

CONCLUSIONS

BAVANS is a very effective surgical procedure that many endoscopic surgeons can perform safely and easily. It has both a cosmetic advantage and excellent curability in endoscopic thyroid cancer surgery.

Clinical Significance of the Histoculture Drug Response Assay in Breast Cancer

BACKGROUND/AIM

Despite the fact that breast cancer patients are generally administered systemic chemotherapy after surgical treatment, predictive factors that allow optimization of chemotherapy are needed. The histoculture drug response assay (HDRA) is a clinically practical in vitro drug-response assay for identifying optimal anticancer agents.

PATIENTS AND METHODS

Thirty-eight primary breast cancer patients who underwent surgical treatment without receiving systemic neoadjuvant therapy were analyzed. We retrospectively examined the relationships between clinicopathological factors and the HDRA results of 5 anticancer agents (mitomycin C (MMC), 5-fluorouracil (5-FU), doxorubicin hydrochloride (ADM), cisplatin (CDDP) and paclitaxel (PTX)).

RESULTS

The relationships between the inhibition rates of anticancer drugs and clinicopathological factors were not significant, except for nuclear grade and venous invasion with the inhibition rate of 5-FU. We also established the threshold inhibition rate for PTX. The paclitaxel inhibition rate was significantly associated with disease-free survival (DFS).

CONCLUSION

HDRA results were independent from the clinicopathological factors of breast cancer patients demonstrating that individualized treatment is needed.

[ONCOPLASTIC BREAST SURGERY AND BREAST RECONSTRUCTION]

Surgical treatment offering both cure and good cosmetic outcomes is important in patients with breast cancer. Mastectomy followed by breast reconstruction is performed with a combination of autologous tissue or implant and can be immediate or delayed in one stage or two stages, respectively. Breast surgeons and plastic surgeons should understand the characteristic indications for surgery and select the appropriate procedure for each patient. Oncoplastic breast surgery (OBS) at the time of breast-conserving surgery is classified into two main methods, volume replacement and volume displacement. It is necessary for clinicians to understand both the advantages and disadvantages of oncoplastic procedures. The problem of some OBS methods remaining ineligible for coverage by national health insurance in Japan remains unresolved, but OBS will become more important as a novel method offering a balance between cancer curability and excellent cosmetic results in the near future.

8q24 Polymorphisms and Diabetes Mellitus Regulate Apolipoprotein A-IV in Colorectal Carcinogenesis

BACKGROUND

Here, we explored the genetic interactions between diabetes and oncogenic single-nucleotide polymorphisms (SNPs) that determine colorectal cancer (CRC) morbidity.

METHODS

8q24 rs6983267 polymorphism analysis and cDNA microarray were performed in 107 CRCs to identify the genes associated with diabetes and the oncogenic SNP. Then clinical significance of the gene was validated in 132 CRCs. Meta-analysis of microarray data and diabetic comorbidity was performed.

RESULTS

Of genes associated with a minor SNP allele at 8q24, diabetes, and MYC overexpression, apolipoprotein A-IV (ApoA-IV) was associated with oncogenesis and poor prognosis in CRC patients. Patients with high ApoA-IV expression showed significantly poorer prognosis by univariate and multivariate analysis. Meta-analysis revealed lipid metabolism was associated with ApoA-IV-related oncogenesis in diabetic patients.

CONCLUSIONS

Changes in lipid metabolism associated with aberrant expression of ApoA-IV were risks for CRC oncogenesis.

Integrated Multiregional Analysis Proposing a New Model of Colorectal Cancer Evolution

Understanding intratumor heterogeneity is clinically important because it could cause therapeutic failure by fostering evolutionary adaptation. To this end, we profiled the genome and epigenome in multiple regions within each of nine colorectal tumors. Extensive intertumor heterogeneity is observed, from which we inferred the evolutionary history of the tumors. First, clonally shared alterations appeared, in which C>T transitions at CpG site and CpG island hypermethylation were relatively enriched. Correlation between mutation counts and patients’ ages suggests that the early-acquired alterations resulted from aging. In the late phase, a parental clone was branched into numerous subclones. Known driver alterations were observed frequently in the early-acquired alterations, but rarely in the late-acquired alterations. Consistently, our computational simulation of the branching evolution suggests that extensive intratumor heterogeneity could be generated by neutral evolution. Collectively, we propose a new model of colorectal cancer evolution, which is useful for understanding and confronting this heterogeneous disease.

Cancer is heterogeneous disease; each tumor in different patients has different cancer genomes. Furthermore, another level of heterogeneity exists: even a single tumor harbors multiple genetically distinct subclones. This intratumor heterogeneity is presumably one of causes of therapeutic difficulty, and its understanding is clinically necessary. In this study, we investigated intratumor heterogeneity in colorectal cancer by analyzing sample obtained from geographically separated regions of 9 colorectal tumors. Our integrated data analyses combined with computational simulation strongly suggest that, after clonally shared alterations were accumulated by aging, numerous subclones were generated by neutral evolution. Importantly, this view can explain the robustness and evolvability of cancer: therapeutic action inducing an environmental change would convert some of the numerous neutral mutations to driver genes that confer therapeutic resistance. We believe that this study not only provides insights into colorectal cancer pathogenesis, but also constitutes a new basis for designing therapeutic strategies.

Clinical and biological significance of transcription termination factor, RNA polymerase I in human liver hepatocellular carcinoma

Recent studies have indicated that increased ribosomal activity contributes to cancer progression. Transcription termination factor, RNA polymerase I (TTF1) acts as a transcription factor for RNA polymerase I. However, the role which TTF1 plays in cancer progression still remains unknown. The present study aimed to determine whether TTF1 plays a critical role in the progression of human liver hepatocellular carcinoma (HCC). In the present study, quantitative real-time reverse transcription polymerase chain reaction was conducted to evaluate TTF1 mRNA expression in 60 HCC tissue samples in order to determine the clinicopathological significance of TTF1. To investigate whether the expression levels of TTF1 were associated known gene signatures which represented ribosomal activity, we applied gene set enrichment analysis (GSEA) to HCC cases in The Cancer Genome Atlas (TCGA) a. We also performed in vitro proliferation assays using TTF1‑overexpressing HCC cells. TTF1 expression was significantly higher in HCC tumor tissues than in adjacent liver tissues (P<0.001). The overall survival (OS) of patients with high TTF1 expression levels was significantly shorter than that of patients with low TTF1 expression (P=0.027). Multivariate analysis indicated that TTF1 expression was an independent prognostic factor for OS (P=0.020). GSEA revealed significant associations between TTF1 expression and gene sets involved in ribosomal function. In vitro, cell proliferation and rRNA transcription were significantly promoted by overexpression of TTF1 in the HCC cell lines HuH-7 and HepG2. From these results, it was suggested that TTF1 participate in poor prognoses and play a role in tumor cell growth in HCC, possibly by upregulating ribosomal activity. In conclusion, we first propose that TTF1 may be a novel biomarker and therapeutic target in HCC. Increased expression of TTF1 was significantly associated with poor prognosis in two independent sets of HCC cases. Furthermore, in vitro experiments provided an explanation for clinical data showing that overexpression of TTF1 contributed to the proliferation of cancer cells.

Clinical Significance of Expression of Nephroblastoma Overexpressed (NOV) in Patients with Colorectal Cancer

BACKGROUND

The nephroblastoma overexpressed (NOV) gene, which belongs to the cysteine-rich, angiogenic inducer 61/connective tissue growth factor/nephroblastoma overexpressed (CCN) family, is located in the 8q24 region and promotes migration and invasiveness in several types of malignancies. We explored the clinical significance of NOV expression in colorectal cancer (CRC).

MATERIALS AND METHODS

NOV expression in CRC specimens and CRC cell lines were evaluated. The association between the clinicopathlogical factors and NOV mRNA expression of tumor tissues was assessed in 126 patients with CRC. We assessed the relationships between NOV expression and overall survival in public databases. We performed overexpression experiments in vitro.

RESULTS

CRC specimens and CRC cell lines showed high NOV expression. High NOV mRNA expression was correlated with poorer overall survival and higher Union for International Cancer Control (UICC) T factor. In public databases, high NOV expression was associated with poorer prognoses. Overexpression of NOV promoted invasiveness of CRC cells.

CONCLUSION

NOV may be an indicator of poor prognosis and a therapeutic target in CRC.

An Integrative Analysis to Identify Driver Genes in Esophageal Squamous Cell Carcinoma

Background

Few driver genes have been well established in esophageal squamous cell carcinoma (ESCC). Identification of the genomic aberrations that contribute to changes in gene expression profiles can be used to predict driver genes.

Methods

We searched for driver genes in ESCC by integrative analysis of gene expression microarray profiles and copy number data. To narrow down candidate genes, we performed survival analysis on expression data and tested the genetic vulnerability of each genes using public RNAi screening data. We confirmed the results by performing RNAi experiments and evaluating the clinical relevance of candidate genes in an independent ESCC cohort.

Results

We found 10 significantly recurrent copy number alterations accompanying gene expression changes, including loci 11q13.2, 7p11.2, 3q26.33, and 17q12, which harbored CCND1, EGFR, SOX2, and ERBB2, respectively. Analysis of survival data and RNAi screening data suggested that GRB7, located on 17q12, was a driver gene in ESCC. In ESCC cell lines harboring 17q12 amplification, knockdown of GRB7 reduced the proliferation, migration, and invasion capacities of cells. Moreover, siRNA targeting GRB7 had a synergistic inhibitory effect when combined with trastuzumab, an anti-ERBB2 antibody. Survival analysis of the independent cohort also showed that high GRB7 expression was associated with poor prognosis in ESCC.

Conclusion

Our integrative analysis provided important insights into ESCC pathogenesis. We identified GRB7 as a novel ESCC driver gene and potential new therapeutic target.

Abstract 1948: In silico screening for novel Wnt/β-catenin pathway target and regulator genes in human hepatocellular carcinoma

Introduction

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and the third leading cause of all cancer deaths worldwide. A fraction of HCC has increased activity of Wnt/β-catenin (Wnt) pathway, which reportedly enhances malignant phenotypes like epithelial-mesenchymal transition (EMT) in various kinds of cancer. Identification of Wnt pathway target and regulator genes gives us better understanding of molecular biological behavior of HCC. In this study, we performed in silico screening for a novel Wnt pathway target and regulator genes in human HCC using public databases.

Method

First, we obtained TCGA data sets of human HCC including mRNA expression (268 samples) and mutational status (198 samples) from the Broad GDAC Firehose web site (gdac.broadinstitute.org/). Next, for β-catenin transcriptional target genes prepared by literature curation, we performed EEM analysis (Niida et al. 2009) on the HCC expression data set to obtain Wnt pathway target genes in HCC. Assuming the sum of mRNA expression of the Wnt pathway target genes as Wnt pathway activity, we then measured association between the pathway alteration and the activity by linear multiple regression analysis ([Wnt pathway activity] = a0 + a1[CTNNB1 mutation] + a2[AXIN1 mutation] + a3[AXIN2 mutation]+a4[APC mutation]+ a5[CTNNB1 mRNA expression] : a0∼a5; partial regression coefficient). By focusing on known epithelial markers (CDH1, KRT18, MUC1, OCLN, TJP1) and mesenchymal markers (ACTA2, CDH2, FN1, VIM, VTN), we also examined association between the Wnt pathway activity and EMT-manifesting genotype. Finally, we performed multiple regression analysis to search for novel Wnt pathway regulator genes ([Wnt pathway activity] = b0 + b1[CTNNB1 mutation] + b2[APC mutation]+ b3[CTNNB1 mRNA expression] + b4[mRNA of a regulator] : b0∼b4; partial regression coefficient).

Result

(1)EEM identified AASS, ASPSCR1, BMP4, C6orf97, DUT, GGH, GNPAT, GREB1, HGD, IKBKAP, ITPR2, LAMA3, LGR5, NEK3, RELN, RHBG, RHOBTB1, SLC13A3, SMYD2, TBX3, TDGF1, TRIB2, VSNL1, ZBTB38 as the Wnt pathway target genes in HCC.

(2)Multiple regression analysis revealed the Wnt pathway activity had strong correlations with CTNNB1 mutation (p-value &lt; 2.00×10-16), APC mutation (p-value = 2.73×10-3), and CTNNB1 expression (p-value = 2.19×10-07)

(3)The Wnt pathway activity had a strong correlation with the EMT genotype (p-value = 3.58×10-4).

(4)We identified 100 statistically significant Wnt pathway regulator candidates (q-values &lt; 1.00×10-10).

Conclusion

Our in silico screening identified novel Wnt pathway target genes in HCC, whose expression profiles were correlated with Wnt pathway alterations and the EMT-manifesting gene signature. We also have predicted Wnt pathway regulator genes, and are now conducting in vitro validation.

Citation Format: Hisateru Komatsu, Atsushi Niida, Masami Ueda, Hidenari Hirata, Ryutaro Uchi, Sho Nambara, Tomoko Saito, Shotaro Sakimura, Yuki Takano, Yoshiaki Shinden, Tomohiro Iguchi, Hidetoshi Eguchi, Keishi Sugimachi, Yuichiro Doki, Masaki Mori, Koshi Mimori. In silico screening for novel Wnt/β-catenin pathway target and regulator genes in human hepatocellular carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1948. doi:10.1158/1538-7445.AM2015-1948

Abstract 218: The new and rapid technique of detecting breast cancer cells using new fluorescent probe ‘gGlu-HMRG’ and its clinical application

Method

After spraying with gGlu-HMRG reagent to the samples, we took images within 5 minutes and analyzed the fluorescence intensity of them. Comparing the changes of fluorescence intensity and pathological evaluations, we examined how this fluorescent method could reflect the pathological status in resected breast tissues (n = 108 from 36 cases), margins of breast conserving surgery specimens (n = 7 from 5 cases) and axillary lymph nodes (n = 149 from 38 cases).

Result

1. The sensitivity and specificity were 92% and 94% respectively for binary classification (normal / abnormal) of various breast tissues.

2. We could detect all malignant lesions in the surface of surgical margins of breast conserving surgery specimens. Additionally, we could detect large tumor-free lesions as fluorescent negative regions.

3. The sensitivity and specificity were 97% and 79% respectively for diagnosing metastatic and non-metastatic axillary lymph nodes.

Discussion and conclusion

It was well feasible to distinguish breast tumor tissues from normal surrounding tissues by this new method. Since it is simple and non-tissue-destructive, it could be readily adopted in the clinical setting. We anticipate that it will reduce costs and the burden on histopathology services in the intraoperative pathological diagnosis of breast conserving surgery and sentinel lymph node biopsy. This technical innovation enable us to visualize tumor cells in the body intraoperatively and evolve the cancer surgery that needs the complete resection of cancer cells.

*1 Urano, Y. et al. Rapid cancer detection by topically spraying a γ-glutamyltranspeptidase-activated fluorescent probe. Sci. Trans. Med. 3, 110ra119 (2011).

Citation Format: Yoshiaki Shinden, Hiroki Ueo, Taro Tobo, Ayako Ganachi, Hisateru Komatsu, Sho Nambara, Tomoko Saito, Masami Ueda, Hidenari Hirata, Shotaro Sakimura, Yuki Takano, Ryutaro Uchi, Tomohiro Iguchi, Hidetoshi Eguchi, Keishi Sugimachi, Yoko Kubota, Yuichiro Kai, Yuko Kijima, Shoji Natsugoe, Hiraki Ueo, Yasuteru Urano, Koshi Mimori. The new and rapid technique of detecting breast cancer cells using new fluorescent probe ‘gGlu-HMRG’ and its clinical application. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 218. doi:10.1158/1538-7445.AM2015-218

Exosomal microRNA in serum is a novel biomarker of recurrence in human colorectal cancer

Background:

Functional microRNAs (miRNAs) in exosomes have been recognised as potential stable biomarkers in cancers. The aim of this study is to identify specific miRNAs in exosome as serum biomarkers for the early detection of recurrence in human colorectal cancer (CRC).

Methods:

Serum samples were sequentially obtained from six patients with and without recurrent CRC. The miRNAs were purified from exosomes, and miRNA microarray analysis was performed. The miRNA expression profiles and copy number aberrations were explored using microarray and array CGH analyses in 124 CRC tissues. Then, we validated exosomal miRNAs in 2 serum sample sets (90 and 209 CRC patients) by quantitative real-time RT–PCR.

Results:

Exosomal miR-17-92a cluster expression level in serum was correlated with the recurrence of CRC. Exosomal miR-19a expression levels in serum were significantly increased in patients with CRC as compared with healthy individuals with gene amplification. The CRC patients with high exosomal miR-19a expression showed poorer prognoses than the low expression group (P<0.001).

Conclusions:

Abundant expression of exosomal miR-19a in serum was identified as a prognostic biomarker for recurrence in CRC patients.

Overexpression of Transcription Termination Factor 1 is Associated with a Poor Prognosis in Patients with Colorectal Cancer

BACKGROUND

RNA polymerase 1 transcription termination factor (TTF1) mediates the transcription of ribosomal RNA (rRNA). In the current study, we investigated the clinical and biological significance of the TTF1 gene in colorectal cancer (CRC).

METHODS

The expression of TTF1 messenger RNA (mRNA) in tumor and normal tissues from 136 patients with CRC was examined by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). We also performed in vitro cell proliferation and migration assays in TTF1-expressing CRC cells. The biological role of TTF1 in CRC was further elucidated using gene set enrichment analysis (GSEA) with CRC samples.

RESULTS

TTF1 expression was significantly higher in tumor tissues than in corresponding normal tissues (p = 0.016). In clinicopathological analysis, the high-TTF1 expression group showed a higher incidence of liver metastasis and lymphatic invasion than the low-TTF1 expression group (p < 0.05), and tended to have more frequent venous invasion than the low-TTF1 expression group. Furthermore, the high-TTF1 expression group had a significantly poorer prognosis than the low-TTF1 expression group (p = 0.011). Moreover, overexpression of TTF1 enhanced the proliferation and migration capacity of CRC cells in vitro. GSEA revealed that TTF1 was significantly associated with the RAS and MYC pathways, and this observation was confirmed in samples from 136 patients with CRC.

CONCLUSION

TTF1 was involved in cancer progression via the RAS and MYC pathways in CRC, suggesting that TTF1 may be a prognostic indicator and therapeutic target in CRC.

A Long Non-coding RNA Activated by Transforming Growth Factor-β is an Independent Prognostic Marker of Gastric Cancer

BACKGROUND

A recent study reported that long non-coding RNA activated by TGF-β (lncRNA-ATB) induced epithelial-mesenchymal transition (EMT) through the transforming growth factor-β (TGF-β)/miR-200s/ZEB axis in hepatocellular carcinoma. Herein, we focused on the clinical significance of lncRNA-ATB in gastric cancer (GC) patients.

MATERIALS AND METHODS

Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was performed to examine expression of lncRNA-ATB, miR-200b, and miR-200c in GC tissues (n = 183). Patients were divided into high and low lncRNA-ATB expression groups using a cutoff of lncRNA-ATB/GAPDH ≥0.60 or <0.60 to determine the clinicopathological significance of lncRNA-ATB in GC. Moreover, we evaluated the expression of TGF-β, lncRNA-ATB, miR-200s, and ZEB1 in GC cell lines by qRT-PCR. GC cell lines were treated by recombinant TGF-β1 or TGF-β receptor inhibitor to examine morphologic changes and genetic alterations, such as lncRNA-ATB, miR-200s, and ZEB1 levels, with respect to the EMT phenotype.

RESULTS

The high lncRNA-ATB group experienced a lower overall survival rate compared with the low lncRNA-ATB group, and multivariate analysis indicated that lncRNA-ATB was an independent prognostic factor (hazard ratio 3.50; 95 % CI 1.73-7.44; p = 0.0004). miR-200c levels were lower and ZEB1 levels were higher in the high lncRNA-ATB group than in the low lncRNA-ATB group. Treatment with TGF-β in GC cell lines resulted in morphological EMT changes, upregulation of lncRNA-ATB and ZEB1, and downregulation of miR-200c and CDH1. SB431542 reduced lncRNA-ATB expression.

CONCLUSION

LncRNA-ATB plays an important role in EMT to promote invasion and metastasis through the TGF-β/miR-200s/ZEB axis, resulting in a poor prognosis in GC. LncRNA-ATB is a novel biomarker of lncRNA, indicative of a poor prognosis in GC patients.

miR-29b is an indicator of prognosis in breast cancer patients

MicroRNA-29b (miR-29b) targets numerous important genes that mediate carcinogenesis and tumor development in breast cancer in vitro and in vivo. The aim of the present study was to determine the clinical significance of miR-29b expression in primary breast cancer patients. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) of miR-29b and certain target genes of miR-29b, such as DNA methyltransferase 3A (DNMT3A), ten-eleven translocation 1 (TET1) and thymine DNA glycosylase (TDG), was performed in 94 primary breast cancer samples. Low expression of miR-29b in primary tumors was significantly associated with poorer disease-free survival (DFS) (P=0.0075) and overall survival (OS) (p=0.0012). Multivariate analysis indicated that miR-29b expression was an independent prognostic factor for OS [relative risk=15.6 (2.33-348), P=0.0026]. In addition, a significant inverse correlation was identified between the expression levels of DNMT3A and miR-29b in estrogen receptor-positive breast cancer patients (P=0.027). To the best of our knowledge, this is the first study to investigate the clinicopathological significance of miR-29b in breast cancer cases and miR-29b is shown to act as a tumor suppressive microRNA in breast cancer and as a potential marker for recurrence and metastasis in breast cancer patients.

Circulating tumour cell-derived plastin3 is a novel marker for predicting long-term prognosis in patients with breast cancer

BACKGROUND

Identification of promising biomarkers that predict the prognosis of patients with breast cancer is needed. In this study, we hypothesised that the expression of the epithelial-mesenchymal transition-related biomarker plastin3 (PLS3) in peripheral blood could be a prognostic factor in breast cancer.

METHODS

We examined PLS3 expression in breast cancer cell lines with epithelial and mesenchymal traits and in circulating tumour cells (CTCs) obtained from the peripheral blood of breast cancer patients. We investigated PLS3 expression in the peripheral blood of 594 patients with breast cancer to evaluate the clinical significance of PLS3 expression.

RESULTS

Robust PLS3 expression was observed in different breast cancer cell lines (Hs578t, MCF-7, MDA-MB-468, and MDA-MB-231) as well as in a bone marrow derived cancer cell line (BC-M1). In both the training (n=298) and validation (n=296) sets, PLS3 expression was observed in CTCs of patients with breast cancer. PLS3-positive patients showed significantly poorer overall and disease-free survival than PLS3-negative patients (P=0.0001 and 0.003, respectively). Subset analysis revealed that this prognostic biomarker was relevant in patients with stage I-III cancer, particularly in patients with luminal-type and triple-negative-type tumours.

CONCLUSIONS

These data demonstrated that PLS3 was expressed in CTCs undergoing the epithelial-mesenchymal transition in patients with breast cancer. Furthermore, PLS3 may be an excellent biomarker for identifying groups at risk of recurrence or with a poor prognosis.

A highly accurate inclusive cancer screening test using Caenorhabditis elegans scent detection

Early detection and treatment are of vital importance to the successful eradication of various cancers, and development of economical and non-invasive novel cancer screening systems is critical. Previous reports using canine scent detection demonstrated the existence of cancer-specific odours. However, it is difficult to introduce canine scent recognition into clinical practice because of the need to maintain accuracy. In this study, we developed a Nematode Scent Detection Test (NSDT) using Caenorhabditis elegans to provide a novel highly accurate cancer detection system that is economical, painless, rapid and convenient. We demonstrated wild-type C. elegans displayed attractive chemotaxis towards human cancer cell secretions, cancer tissues and urine from cancer patients but avoided control urine; in parallel, the response of the olfactory neurons of C. elegans to the urine from cancer patients was significantly stronger than to control urine. In contrast, G protein α mutants and olfactory neurons-ablated animals were not attracted to cancer patient urine, suggesting that C. elegans senses odours in urine. We tested 242 samples to measure the performance of the NSDT, and found the sensitivity was 95.8%; this is markedly higher than that of other existing tumour markers. Furthermore, the specificity was 95.0%. Importantly, this test was able to diagnose various cancer types tested at the early stage (stage 0 or 1). To conclude, C. elegans scent-based analyses might provide a new strategy to detect and study disease-associated scents.

A long noncoding RNA, lncRNA-ATB, is involved in the progression and prognosis of colorectal cancer

BACKGROUND/AIM

A long noncoding RNA (lncRNA) activated by transforming growth factor (TGF)-β (lncRNA-ATB) was recently described to promote the invasion-metastasis cascade in hepatocellular carcinoma. The aim of the present study was to clarify the clinicopathological role and prognostic relevance of lncRNA-ATB in colorectal cancer (CRC).

MATERIALS AND METHODS

lncRNA-ATB expression was evaluated by real-time reverse transcription polymerase chain reaction in 124 patients with CRC. Patients were divided into two groups based on the median lncRNA-ATB expression.

RESULTS

High lncRNA-ATB expression was significantly associated with greater tumor size, depth of tumor invasion, lymphatic invasion, vascular invasion, and lymph node metastasis. Patients of the high-lncRNA-ATB expression group had significantly poorer outcomes than those of the low-expression group. Additionally, levels of lncRNA-ATB expression were significantly higher in patients with hematogenous metastases.

CONCLUSION

lncRNA-ATB may be involved in the progression of CRC and be a novel indicator of poor prognosis in patients with CRC.

The miR-506-Induced Epithelial-Mesenchymal Transition is Involved in Poor Prognosis for Patients with Gastric Cancer

BACKGROUND

MicroRNAs have roles in the regulation of the epithelial-mesenchymal transition (EMT). Findings have shown that miR-506 inhibits the expression of SNAI2 and that low expression of miR-506 is associated with poor prognoses in ovarian and breast cancers. This study investigated the role of miR-506 in survival and the EMT in patients with gastric cancer.

METHODS

In this study, miR-506 and SNAI2 mRNA levels were measured in 141 cases of gastric cancer by quantitative reverse transcription polymerase chain reaction, and the protein expressions of SNAI2 and E-cadherin in 39 cases were validated by immunohistochemical analysis. Next, the associations between their expression levels and clinicopathologic factors were evaluated. In addition, cell proliferation, migration, and luciferase activity of the 3' untranslated region (UTR) of SNAI2 were analyzed using pre-miR-506 precursor in two human gastric cancer cell lines.

RESULTS

Low expression of miR-506 was significantly correlated with poor overall survival in both the univariate analysis (P = 0.016) and the multivariate analysis (P < 0.05). Low miR-506 expression was significantly correlated with high SNAI2 expression (P = 0.009) and poorly differentiated type (P = 0.015). In vitro, miR-506 suppressed SNAI2 expression by binding to its 3'UTR, resulting in increased expression of E-cadherin (P < 0.05), verified by immunohistochemical analysis. Pre-miR-506 transfected cells showed significantly suppressed cell proliferation and migration (P < 0.05) compared with the control cells.

CONCLUSIONS

The EMT was directly suppressed by miR-506, and its low expression was an independent prognostic factor in gastric cancer patients. The data indicated that miR-506 may act as a tumor suppressor and could be a novel therapeutic agent.

Identification of a bona fide microRNA biomarker in serum exosomes that predicts hepatocellular carcinoma recurrence after liver transplantation

Background

Predictive biomarkers for the recurrence of hepatocellular carcinoma (HCC) have great benefit in the selection of treatment options, including liver transplantation (LT), for HCC. The purpose of this study was to identify specific microRNAs (miRs) in exosomes from the serum of patients with recurrent HCC and to validate these molecules as novel biomarkers for HCC recurrence.

Methods

We employed microarray-based expression profiling of miRs derived from exosomes in the serum of HCC patients to identify a biomarker that distinguishes between patients with and without HCC recurrence after LT. This was followed by the validation in a separate cohort of 59 HCC patients who underwent living related LT. The functions and potential gene targets of the recurrence-specific miRs were analysed using a database, clinical samples and HCC cell lines.

Results

We found that miR-718 showed significantly different expression in the serum exosomes of HCC cases with recurrence after LT compared with those without recurrence. Decreased expression of miR-718 was associated with HCC tumour aggressiveness in the validated cohort series. We identified HOXB8 as a potential target gene of miR-718, and its upregulation was associated with poor prognosis.

Conclusion

Circulating miRs in serum exosomes have potential as novel biomarkers for predicting HCC recurrence.

Diminished expression of MiR-15a is an independent prognostic marker for breast cancer cases

BACKGROUND/AIM

MiR-15a targets Cyclin E1 (CCNE1), which regulates the cell cycle and promotes cell proliferation and progression. Herein, we investigated the clinicopathological significance of miR-15a as a prognostic marker in breast cancer (BC) cases.

MATERIALS AND METHODS

We collected primary tumor samples of 230 BC cases, including 68 triple-negative cases. The expression levels of miR-15a in primary tumors were measured by qRT-PCR assay.

RESULTS

Low expression of miR-15a in primary tumors was significantly correlated with shorter disease-free survival (p=0.0012) and overall survival (p=0.005) compared to the high miR-15a expression in triple-negative BC cases. Multivariate analysis indicated that low miR-15a expression was an independent prognostic factor for overall survival [RR=2.56(1.03-7.18), p=0.04].

CONCLUSION

MiR-15a expression levels could be a promising biological and prognostic marker for overall survival especially in triple-negative BC cases.

Downregulation of PRRX1 Confers Cancer Stem Cell-Like Properties and Predicts Poor Prognosis in Hepatocellular Carcinoma

BACKGROUND

Downregulation of paired related homeobox 1 (PRRX1) is associated with the acquisition of cancer stem cell (CSC)-like properties and poor prognosis in cancers. The purpose of this study is to clarify the role of PRRX1 expression in predicting prognosis and mediating CSC-like properties in hepatocellular carcinoma (HCC).

METHODS

The association between PRRX1 expression and overall survival (OS) of patients with HCC was analyzed in three independent datasets: 62 resected primary cases, 242 cases from GSE14520, and 162 cases from The Cancer Genome Atlas (TCGA). A cell line expressing PRRX1 (HuH7) was established for the functional analyses. The ability to form spheres, the expression levels of the hepatic CSC surface markers (CD13, CD133, and EpCAM), in vitro chemosensitivity to 5-fluorouracil (FU), and radiosensitivity were evaluated.

RESULTS

Univariate and multivariate analyses showed that the 5-year OS of the low PRRX1 expression group was significantly poorer than that of the high PRRX1 expression group (P = 0.024 and P = 0.045, respectively). Consistent with this, the low PRRX1 expression group in GSE14520 and TCGA datasets showed significantly shorter OS (P = 0.027 and P = 0.010, respectively). Gene set enrichment analysis on GSE14520 and TCGA datasets indicated that downregulation of PRRX1 was correlated with the stemness signature. The number of spheres and the expression levels of CSC markers were significantly decreased when PRRX1 was expressed. Moreover, PRRX1 impaired resistance to 5-FU and radiation.

CONCLUSIONS

Downregulation of PRRX1 expression contributes to the poor prognosis of patients with HCC through acquisition of CSC-like properties.

Abstract 1138: Aberrant expression of Plastin3 (PLS3) induces liver metastasis via enhancing the epithelial-mesenchymal transition and stemness in colorectal cancer (CRC)

Background

PLS3 gene, located on chromosome Xq23, encodes a protein 10 product (PLS3) that reduces F-actin disassembly and inhibits cofilin-mediated depolymerization of actin fibers. We previously reported that PLS3 is a novel marker for circulating tumor cells in colorectal cancer (CRC), and the high expression of PLS3 in tumor tissue is associated with a poor prognosis in patients with primary CRC. In this study, we investigated its role in functional significance for metastatic potential of CRC performing in vitro and in vivo studies.

Method

Four patients with surgically resected both primary CRC and liver metastasis were included in this study. Those tissues were performed with the PLS3-immunohistochemical examination (PLS3-IHC). In vitro, we cultured LOVO, DLD-1 and HCT116 which caused no liver metastasis by injecting them into the spleen of NOD/SCID mice. We stably enhanced the expression of PLS3 in the cells by transfecting the lentiviral vector expressing PLS3. The expression levels of EMT-related genes were examined with real time RT-PCR. The migration, invasion and sphere formation assay were also performed. In vivo, NOD/SCID mice were divided into two groups, which included mice transplanted with only PLS3-transfected cells and mice transplanted with PLS3-transfected and PLS3-attenuated cells together, by injecting into the spleen. We calculated the established primary splenic tumors and liver metastasis. PLS3-IHC was also performed to the sacrificed tissues.

Result

(1) In the PLS3-IHC of four CRC samples, all the liver metastasis tissues included stained areas, but only one primary tissue showed PLS3-staining. This was the evidence that cancer cells expressing PLS3 had metastatic properties.

(2) PLS3-transfected cells had the significant decrease of E-cadherin, while the expression levels of TWIST, ZEB and vimentin were significantly higher in PLS3-transfected than PLS3-attenuated cells. PLS3-transfected LOVO significantly induced invasion and migration, compared to PLS3-attenuatd LOVO. In the sphere formation assay, the high expression of PLS3 significantly increased the proportion of sphere generating cells (DLD-1) (p&lt;0.001).

(3) In vivo, PLS3-transfected cells (DLD-1 and HCT116) significantly induced the growth of liver metastasis. The volumes of liver metastasis of mice transplanted with the mixtures were significantly smaller than those of only PLS3-transfected cells. The liver metastasis tissues showed only stained areas in both groups in PLS3-IHC. However, the established splenic tumor of mice transplanted with the mixtures displayed not only the stained but also the nonstained areas in PLS3-IHC.

Conclusion

In conclusion, our study suggests experimental evidence to support the functional significance of PLS3 to induce epithelial-mesenchymal trandition, stemness and liver metastasis of human CRC.

Citation Format: Masami Ueda, Keishi Sugimachi, Junji Kurashige, Shotarou Sakimura, Hidenari Hirata, Ryutarou Uchi, Yuki Takano, Hiroki Ueo, Tae Matsumura, Yoshiaki Shinden, Hidetoshi Eguchi, Tomoya Sudo, Masaki Mori, Koshi Mimori. Aberrant expression of Plastin3 (PLS3) induces liver metastasis via enhancing the epithelial-mesenchymal transition and stemness in colorectal cancer (CRC). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1138. doi:10.1158/1538-7445.AM2014-1138

Abstract 1478: Decreased expression of miR-506 induced epithelial-mesenchymal transition and poor prognosis in gastric cancer patients

Backgrounds/Aims

Most gastric cancer cells acquire epithelial-mesenchymal transition (EMT) to promote malignant cells to form metastasis in gastric cancer cases. Recent studies proved the roles of microRNAs on the regulation of EMT through suppressing EMT-related transcription factors. Of those, miR-506 inhibits expression of SNAI2 and PRRX1 and aberrant low expression of miR-506 relates to poor prognosis in ovarian and breast cancers. The aim of this study is to investigate the role of miR-506 on survival and EMT in Japanese gastric cancer (GC) patients.

Methods

144 patients with surgically resected primary GC were included in this study. MicroRNA and mRNA were measured using real-time PCR analysis. Clinicopathological factors including prognosis that were dependent on miR-506 expression were analyzed. In vitro, we established miR-506 overexpressing human GC cell lines (MKN-7 and MKN-45). The proliferation, migration and luciferase assay of 3′UTR of SNAI2 were performed.

Results

(1) The low expression of miR-506 was significantly correlated with poor overall survival in the univariate model (log-rank p = 0.02 ) and multivariate model (hazard ratio = 1.78, p = 0.05). The miR-506 expression was inversely correlated with SNAI2 expression (p = 0.01). The low expression of miR-506 was significantly correlated with histologically poorer differentiation that showed more invasive properties (p = 0.02). (2) In miR-506 overexpressed GC cell lines, miR-506 suppressed the SNAI2 expression by binding to 3′UTR of SNAI2 gene, and resulted in the increased expression of E-cadherin. MiR-506 overexpression significantly suppressed the cell proliferation and the cell migration compared to the miR-control transfected cells.

Conclusions

This study showed that miR-506 directly controlled EMT by regulating SNAI2, and was a independent prognostic factor in Japanese GC patients. Our data indicated that miR-506 could be a candidate of EMT inhibitor in GC patients.

Univariate and multivariate analysis of clinicopathological features for 5-year overall survivalUnivariate analysisMultivariate analysisFeaturesHR95%CIP valueHR95%CIP valueAge (&gt;70/70≥)0.6260.345-1.0890.099---Gender (male/female)1.4910.844-2.7810.174---Histological grade(Well & Moderately/Poorly & others)1.6470.959-2.8920.071Depth(T1, 2/T3, 4)4.9572.389-12.040&lt;0.001*1.9320.777-5.3920.162Lymph node metastasis (absent/present)5.3632.581-13.038&lt;0.001*2.9371.245-7.9510.012*Venous invasion (absent/present)3.1641.859-5.420&lt;0.001*1.3640.753-2.5000.307Peritoneum metastasis (absent/present)4.9332.635-8.928&lt;0.001*2.6901.391-5.0620.004*Stage I, II/III, IV5.4292.948-10.780&lt;0.001*---miR-506 expression (low/high)2.0171.149-3.7130.014*1.7751.002-3.3000.049**p&lt;0.05, HR hazard ratio, CI 95% confidence interval

Citation Format: Shotaro Sakimura, Junji Kurashige, Keishi Sugimachi, Masami Ueda, Hidenari Hirata, Yoshiaki Shinden, Etsuko Sakimura, Tae Matsumura, Yuki Takano, Ryutaro Uchi, Hiroki Ueo, Hidetoshi Eguchi, Tomoya Sudo, Sumio Hoka, Koshi Mimori. Decreased expression of miR-506 induced epithelial-mesenchymal transition and poor prognosis in gastric cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1478. doi:10.1158/1538-7445.AM2014-1478

Abstract 3882: Downregulation of PRRX1 confers cancer stem cell-like properties and poor prognosis in hepatocellular carcinoma

Background:

Recent studies have been focused on the relationship between cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT). Unlike classical EMT inducers, PRRX1 is involved in the acquisition of CSC-like properties when its down-regulation induces mesenchymal-epithelial transition in breast cancer. Meanwhile, hepatocellular carcinoma (HCC) is one of the most intractable malignancies, and it is required to identify a bona-fide molecular target to regulate tumor progression and the treatment resistance. The purpose of this study is to investigate the role of PRRX1 expression on clinical significance and CSC-like properties in HCC.

Methods:

(1) PRRX1 expression was analyzed in 62 resected primary HCC cases by quantitative RT-PCR (qRT-PCR). Clinicopathological factors and overall survival (OS) according to PRRX1 expression were analyzed. (2) The gene set enrichment analysis (GSEA) on the published clinical data set of 242 HCC samples (GSE14520) was applied to investigate the association of PRRX1 expression levels and the stem cell-like properties. (3) PRRX1 stably expressing HCC cell lines (HuH7) were established using a lentiviral vector. The expression levels of the hepatic CSC surface markers (CD13, CD133 and EpCAM) were analyzed by flowcytometry and qRT-PCR. Furthermore, the ability of sphere formation and in vitro chemosensitivity to 5-FU were evaluated to assess the CSC-like properties.

Results:

(1) Univariate analysis showed that 5-year OS of the low PRRX1 expression group was significantly shorter than that of the high PRRX1 expression group (49.8% vs. 80.3%, P=0.014). On multivariate analysis, low PRRX1 expression was an independent prognostic factor for HCC (P=0.026). (2) GSEA analysis on the 247 HCC data set indicated that the down-regulation of PRRX1 was significantly correlated with the stem cell signature (P=0.039). Furthermore, using gene sets of polycomb repressive complex 2 (PCR2) targets and H3 lysine-27 trimethylation mediated by PCR2, HCC with low PRRX1 expression showed parallel enrichment patterns with human embryonic stem cells (P=0.002 and P&lt;0.001, respectively). These results suggested that down-regulation of PRRX1 in HCC induces the acquisition of CSC-like properties through modification of chromatin structure. (3) The level of CSC markers (CD13, CD133 and EpCAM) and the number of spheres were significantly decreased in PRRX1-expressing HuH7 cells compared with the controls. Moreover, PRRX1 impaired resistance to 5-FU in HCC cells.

Conclusions:

The down-regulation of PRRX1 expression contributes to the poor prognosis through the acquisition of CSC-like properties in HCC patients. We might apply the aberrant expression of PRRX1 as a novel clinical biomarker for prediction of the malignant potential in HCC cases.

Citation Format: Hidenari Hirata, Keishi Sugimachi, Ryutaro Uchi, Junji Kurashige, Tae Matsumura, Yuki Takano, Hiroki Ueo, Masami Ueda, Shotaro Sakimura, Yoshiaki Shinden, Hidetoshi Eguchi, Tomoya Sudo, Masakazu Hirakawa, Hiroshi Honda, Koshi Mimori. Downregulation of PRRX1 confers cancer stem cell-like properties and poor prognosis in hepatocellular carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3882. doi:10.1158/1538-7445.AM2014-3882