Stromal-derived MAOB promotes prostate cancer growth and progression.

Prostate cancer (PC) develops in a microenvironment where the stromal cells modulate adjacent tumor growth and progression. Here, we demonstrated elevated levels of monoamine oxidase B (MAOB), a mitochondrial enzyme that degrades biogenic and dietary monoamines, in human PC stroma, which was associated with poor clinical outcomes of PC patients. Knockdown or overexpression of MAOB in human prostate stromal fibroblasts indicated that MAOB promotes cocultured PC cell proliferation, migration, and invasion and co-inoculated prostate tumor growth in mice. Mechanistically, MAOB induces a reactive stroma with activated marker expression, increased extracellular matrix remodeling, and acquisition of a protumorigenic phenotype through enhanced production of reactive oxygen species. Moreover, MAOB transcriptionally activates CXCL12 through Twist1 synergizing with TGFß1-dependent Smads in prostate stroma, which stimulates tumor-expressed CXCR4-Src/JNK signaling in a paracrine manner. Pharmacological inhibition of stromal MAOB restricted PC xenograft growth in mice. Collectively, these findings characterize the contribution of MAOB to PC and suggest MAOB as a potential stroma-based therapeutic target.

Cholinergic signaling via muscarinic M1 receptor confers resistance to docetaxel in prostate cancer.

Docetaxel is the most commonly used chemotherapy for advanced prostate cancer (PC), including castration-resistant disease (CRPC), but the eventual development of docetaxel resistance constitutes a major clinical challenge. Here, we demonstrate activation of the cholinergic muscarinic M1 receptor (CHRM1) in CRPC cells upon acquiring resistance to docetaxel, which is manifested in tumor tissues from PC patients post- vs. pre-docetaxel. Genetic and pharmacological inactivation of CHRM1 restores the efficacy of docetaxel in resistant cells. Mechanistically, CHRM1, via its first and third extracellular loops, interacts with the SEMA domain of cMET and forms a heteroreceptor complex with cMET, stimulating a downstream mitogen-activated protein polykinase program to confer docetaxel resistance. Dicyclomine, a clinically available CHRM1-selective antagonist, reverts resistance and restricts the growth of multiple docetaxel-resistant CRPC cell lines and patient-derived xenografts. Our study reveals a CHRM1-dictated mechanism for docetaxel resistance and identifies a CHRM1-targeted combinatorial strategy for overcoming docetaxel resistance in PC.

Neuropilin-2 promotes lineage plasticity and progression to neuroendocrine prostate cancer.

Neuroendocrine prostate cancer (NEPC), a lethal subset of prostate cancer, is characterized by loss of AR signaling and resulting resistance to AR-targeted therapy during neuroendocrine transdifferentiation, for which the molecular mechanisms remain unclear. Here, we report that neuropilin 2 (NRP2) is upregulated in both de novo and therapy-induced NEPC, which induces neuroendocrine markers, neuroendocrine cell morphology, and NEPC cell aggressive behavior. NRP2 silencing restricted NEPC tumor xenograft growth. Mechanistically, NRP2 engages in reciprocal crosstalk with AR, where NRP2 is transcriptionally inhibited by AR, and in turn suppresses AR signaling by downregulating the AR transcriptional program and confers resistance to enzalutamide. Moreover, NRP2 physically interacts with VEGFR2 through the intracellular SEA domain to activate STAT3 phosphorylation and subsequently SOX2, thus driving NEPC differentiation and growth. Collectively, these results characterize NRP2 as a driver of NEPC and suggest NRP2 as a potential therapeutic target in NEPC.

Biomarker profile of invasive lobular carcinoma: pleomorphic versus classic subtypes, clinicopathological characteristics and prognosis analyses.

PURPOSE: To compare the clinicopathologic features and prognosis of pleomorphic invasive lobular carcinoma (P-ILC) and classic ILC (C-ILC) according to the biomarker profile. METHODS: A total of 667 C-ILCs and 133 P-ILCs between 2011 and 2021 were included. Clinicopathologic features and stromal tumor-infiltrating lymphocytes (sTILs) status were evaluated. P-ILCs were divided into subtypes based on ER/PR and HER2 expression. The overall survival and disease-free survival (DFS) of patients were compared among matched P-ILCs, C-ILCs, and invasive ductal carcinomas (IDCs) with biomarker subtypes. RESULTS: Compared to C-ILCs, P-ILCs had greater tumor sizes and stages, fewer ER-positive, more HER2-positive, triple negative (TN), and Ki-67 > 20% tumors (P < 0.05). P-ILCs were subdivided into ER+ (63.1%), HER2+ (21.1%) and TN (15.8%). ER+ P-ILCs were mainly showed trabecular and solid growth patterns. Apocrine and solid features were more strongly associated with HER2+ P-ILCs and TN-P-ILCs, respectively. The prognosis of each biomarker group (ER+, HER2+ and TN) differed by subtype. The P-ILC biomarker subtypes had worse prognosis than the same subtypes in the IDC group, while there was no difference between the P-ILC and the C-ILC counterparts. Solid variants of P-ILC had the worst prognosis. Bone was the most common metastatic site in ER+ P-ILCs and TN-P-ILCs. HER2+ P-ILCs tended to metastasize to the brain and liver. DFS of HER2+ P-ILCs and TN-P-ILCs were worse than that of ER+ P-ILCs. Lacking lobular carcinoma in situ and sTILs ≤ 10% were associated with worse survival of ER+ P-ILCs and TN-P-ILCs, respectively. For HER2+ P-ILCs, Ki-67 > 20% and sTILs ≤ 10% were significant factors for lower DFS. CONCLUSION: P-ILCs is an aggressive subtype of ILCs. Analyzing the prognostic factors of P-ILCs with heterogeneous morphological and biomarker characteristics is helpful for creating an individualized treatment.

Genomic landscape of secretory carcinoma of the breast with axillary lymph node metastasis.

OBJECTIVE: Secretory carcinoma of the breast (SCB) is a rare low-grade often triple-negative breast carcinoma. We aim to analyze the pathological and molecular features of 21 SCBs, especially the SCBs with axillary lymph node metastasis. METHODS: The clinicopathological characteristics of 21 SCBs were reviewed. Breast biomarkers, Pan-TRK and ETV6 break, and ETV6-NTRK3 fusion were performed on all cases. Next-Generation Sequencing (NGS) was performed on two cases with lymph node metastasis. RESULTS: 21 SCBs consisted of 2 men and 19 women aged 5～73 years (median 43 years), with a mean 2.1 cm (range 0.5～3.5 cm) tumor size. 90.1% (19/21) cases had mixed microcystic, solid, tubular, and papillary patterns. Pan-TRK and S100 are positive in 95% (20/21) and 90% (19/21) of cases, respectively. Tumor markers ER, PR, and HER2 expressions were 62% (13/21), 33% (7/21), and 0% (0/21). All cases showed ETV6 (21/21) rearrangement and ETV6-NTRK3 (11/11) fusion. 57% (12/21) of the cases had a balanced translocation and 38% (8/21) with unbalanced signals of ETV6. There was no clinical difference between balanced and unbalanced translocations in histological morphology and other prognosis factors. Furthermore, one case (#4) had a duplication of the ETV6 gene and presented axillary lymph node metastasis. NGS analysis revealed simple genomes, low tumor mutation burden, stable microsatellite sites, and single nucleotide polymorphism (SNP) heterozygous mutation in both SCBs with nodal metastasis. CONCLUSION: SCB is an indolent invasive carcinoma, even the cases with axillary lymph node metastasis, presenting simple genomes. Duplication of ETV6 cases may indicate lymph node metastasis.

Clinicopathologic characteristics of HER2-positive metaplastic squamous cell carcinoma of the breast.

AIMS: The aim of this study was to analyse the clinicopathological features and prognosis of human epidermal growth factor receptor-2 (HER2)-positive metaplastic squamous cell carcinoma (MSCC). METHODS: Fifty-eight patients with MSCC of the breast who were classified into 45 triple-negative and 13 HER2-positive subgroups diagnosed at the West China Hospital, Sichuan University, from 2004 to 2018, were enrolled. Clinicopathological features were collected and compared between HER2-positive MSCC, triple-negative MSCC, HER2-positive invasive breast carcinoma of no special type (NST) and triple-negative NST groups. In the prognostic survival analysis, HER2-positive MSCCs was compared with triple-negative MSCCs, HER2-positive NSTs and triple-negative NSTs. RESULTS: Compared with triple-negative MSCCs, more patients with Ki-67 low expression were in HER2-positive MSCCs (p<0.05). More patients with HER2-positive MSCC than patients with HER2-positive NST were postmenopausal (p<0.05). Compared among HER2-positive MSCCs, triple-negative MSCCs and triple-negative NSTs, patients of HER2-positive MSCCs with high Ki-67 expression were the least, and HER2-positive MSCCs had more strongly associated with postmenopausal disease status (p<0.05). In survival analyses, HER2-positive MSCCs had a high risk of recurrence and poor prognosis (p<0.05). Lymph node status was significantly associated with the disease-free survival of patients with HER2-positive MSCC. CONCLUSION: In conclusion, our study indicates that HER2-positive MSCC is an aggressive disease with unique clinicopathological characteristics. Both HER2-positive status and an SCC component are critical factors for poor prognosis. HER2-positive MSCC and triple-negative MSCC are distinct subgroups. Corresponding targeted therapy recommendations should be made for this HER2-positive MSCC group.

Bidirectional Cross-talk between MAOA and AR Promotes Hormone-Dependent and Castration-Resistant Prostate Cancer.

Androgen receptor (AR) is the primary oncogenic driver of prostate cancer, including aggressive castration-resistant prostate cancer (CRPC). The molecular mechanisms controlling AR activation in general and AR reactivation in CRPC remain elusive. Here we report that monoamine oxidase A (MAOA), a mitochondrial enzyme that degrades monoamine neurotransmitters and dietary amines, reciprocally interacts with AR in prostate cancer. MAOA was induced by androgens through direct AR binding to a novel intronic androgen response element of the MAOA gene, which in turn promoted AR transcriptional activity via upregulation of Shh/Gli-YAP1 signaling to enhance nuclear YAP1-AR interactions. Silencing MAOA suppressed AR-mediated prostate cancer development and growth, including CRPC, in mice. MAOA expression was elevated and positively associated with AR and YAP1 in human CRPC. Finally, genetic or pharmacologic targeting of MAOA enhanced the growth-inhibition efficacy of enzalutamide, darolutamide, and apalutamide in both androgen-dependent and CRPC cells. Collectively, these findings identify and characterize an MAOA-AR reciprocal regulatory circuit with coamplified effects in prostate cancer. Moreover, they suggest that cotargeting this complex may be a viable therapeutic strategy to treat prostate cancer and CRPC. SIGNIFICANCE: MAOA and AR comprise a positive feedback loop in androgen-dependent and CRPC, providing a mechanistic rationale for combining MAOA inhibition with AR-targeted therapies for prostate cancer treatment.

MAOA promotes prostate cancer cell perineural invasion through SEMA3C/PlexinA2/NRP1-cMET signaling.

Perineural invasion (PNI), a pathologic feature defined as cancer cell invasion in, around, and through nerves, is an indicator of poor prognosis and survival in prostate cancer (PC). Despite widespread recognition of the clinical significance of PNI, the molecular mechanisms are largely unknown. Here, we report that monoamine oxidase A (MAOA) is a clinically and functionally important mediator of PNI in PC. MAOA promotes PNI of PC cells in vitro and tumor innervation in an orthotopic xenograft model. Mechanistically, MAOA activates SEMA3C in a Twist1-dependent transcriptional manner, which in turn stimulates cMET to facilitate PNI via autocrine or paracrine interaction with coactivated PlexinA2 and NRP1. Furthermore, MAOA inhibitor treatment effectively reduces PNI of PC cells in vitro and tumor-infiltrating nerve fiber density along with suppressed xenograft tumor growth and progression in mice. Collectively, these findings characterize the contribution of MAOA to the pathogenesis of PNI and provide a rationale for using MAOA inhibitors as a targeted treatment for PNI in PC.

WLS-Wnt signaling promotes neuroendocrine prostate cancer.

Neuroendocrine prostate cancer (NEPC) is a lethal prostate cancer subtype arising as a consequence of more potent androgen receptor (AR) targeting in castration-resistant prostate cancer (CRPC). Its molecular pathogenesis remains elusive. Here, we report that the Wnt secretion mediator Wntless (WLS) is a major driver of NEPC and aggressive tumor growth in vitro and in vivo. Mechanistic studies showed that WLS is a transcriptional target suppressed by AR that activates the ROR2/PKCδ/ERK signaling pathway to support the neuroendocrine (NE) traits and proliferative capacity of NEPC cells. Analysis of clinical samples and datasets revealed that WLS was highly expressed in CRPC and NEPC tumors. Finally, treatment with the Wnt secretion inhibitor LGK974 restricted NE prostate tumor xenograft growth in mice. These findings collectively characterize the contribution of WLS to NEPC pathogenesis and suggest that WLS is a potential therapeutic target in NEPC.

Prognostic Score-Based Stratification Analysis Reveals Universal Benefits of Radiotherapy on Lowering the Risk of Ipsilateral Breast Event for Ductal Carcinoma In Situ Patients with Different Risk Levels.

BACKGROUND: We aimed to analyze the effects of radiotherapy (RT) on the incidence rate of ipsilateral breast event (IBE) in ductal carcinoma in situ (DCIS) patients with lumpectomy after being stratified by prognostic score. METHODS: We identified DCIS patients who received lumpectomy, from the Surveillance, Epidemiology, and End Results (SEER) database from 1988 to 2015. Cumulative incidence functions for competing risk were used to evaluate the effects of RT on IBE risk over time. Three multivariate regression models (weighted, non-weighted, and Fine-Gray) were applied to compare the IBE risk between the RT and non-RT groups after stratifying patients by prognostic score. RESULTS: Overall, 72,623 DCIS patients were identified from the SEER database and 49,206 (66.8%) patients received RT. During the follow-up period (ranging from 7 to 347 months), the cumulative probability of invasive and in situ IBE was significantly lower in the RT group than in the non-RT group (p < 0.001). After being stratified by prognostic score, the weighted IBE incidence rate increased as the risk level increased (p < 0.050). In multivariate regression models, RT lowered the IBE incidence rate by at least 30% in low-, moderate-, and high-risk DCIS (p < 0.010). In particular, the in situ and invasive IBE incidence rate decreased by over 50% in low-risk DCIS with RT (p < 0.001). CONCLUSIONS: RT is associated with a lowered IBE incidence rate in DCIS patients, regardless of the assigned risk levels for patients. The significant reduction in the IBE incidence rate in low-risk DCIS patients also indicates the potential benefits for recommending RT to such a patient population in clinical practice.

Multidimensional Machine Learning Personalized Prognostic Model in an Early Invasive Breast Cancer Population-Based Cohort in China: Algorithm Validation Study.

BACKGROUND: Current online prognostic prediction models for breast cancer, such as Adjuvant! Online and PREDICT, are based on specific populations. They have been well validated and widely used in the United States and Western Europe; however, several validation attempts in non-European countries have revealed suboptimal predictions. OBJECTIVE: We aimed to develop an advanced breast cancer prognosis model for disease progression, cancer-specific mortality, and all-cause mortality by integrating tumor, demographic, and treatment characteristics from a large breast cancer cohort in China. METHODS: This study was approved by the Clinical Test and Biomedical Ethics Committee of West China Hospital, Sichuan University on May 17, 2012. Data collection for this project was started in May 2017 and ended in March 2019. Data on 5293 women diagnosed with stage I to III invasive breast cancer between 2000 and 2013 were collected. Disease progression, cancer-specific mortality, all-cause mortality, and the likelihood of disease progression or death within a 5-year period were predicted. Extreme gradient boosting was used to develop the prediction model. Model performance was assessed by calculating the area under the receiver operating characteristic curve (AUROC), and the model was calibrated and compared with PREDICT. RESULTS: The training, test, and validation sets comprised 3276 (499 progressions, 202 breast cancer-specific deaths, and 261 all-cause deaths within 5-year follow-up), 1405 (211 progressions, 94 breast cancer-specific deaths, and 129 all-cause deaths), and 612 (109 progressions, 33 breast cancer-specific deaths, and 37 all-cause deaths) women, respectively. The AUROC values for disease progression, cancer-specific mortality, and all-cause mortality were 0.76, 0.88, and 0.82 for training set; 0.79, 0.80, and 0.83 for the test set; and 0.79, 0.84, and 0.88 for the validation set, respectively. Calibration analysis demonstrated good agreement between predicted and observed events within 5 years. Comparable AUROC and calibration results were confirmed in different age, residence status, and receptor status subgroups. Compared with PREDICT, our model showed similar AUROC and improved calibration values. CONCLUSIONS: Our prognostic model exhibits high discrimination and good calibration. It may facilitate prognosis prediction and clinical decision making for patients with breast cancer in China.

High expression of microRNA20b is associated with malignant clinicopathological features and poor prognosis in breast phyllodes tumor.

BACKGROUND: microRNAs, which expound the transcriptional regulation of gene expression, have been validated as prognostic markers in many tumors. The deregulated expression of microRNAs has been shown to aid classification of tumors and predict outcome in many tumors including breast PTs. The aim of our study is to investigate the clinical significance and prognostic value of microRNAs in PTs to identify a biomarker which has the potential for predicting prognosis and target therapy. METHODS: Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of microRNA20b in 123 breast PTs patients. The correlations between the expression of microRNA20b and clinicopathological parameters were investigated. The prognostic significance of microRNA20b was investigated by the Kaplan-Meier survival and Cox proportional hazards regression model. RESULTS: The expression level of microRNA20b increased with the increase in the tumor grade (p < 0.05). High expression of microRNA20b correlated with stromal overgrowth, marked stromal cellularity, high atypia of stromal cells, infiltrative tumor margin, high mitotic activity, tumor grade, local recurrence and metastasis (p < 0.05). High expression of microRNA20b correlated with the shorter disease-free survival (DFS) (log-rank test, p < 0.001). Multivariate Cox regression analysis showed that microRNA20b was an independent prognostic indicator for breast PTs patients. CONCLUSION: The study demonstrated the promising potential of applying microRNA20b as a prognostic biomarker in PT patients.

MAOA-mediated reprogramming of stromal fibroblasts promotes prostate tumorigenesis and cancer stemness.

The tumor microenvironment plays a critical role in prostate cancer (PC) development and progression. Inappropriate activation of the stroma potentiates the growth and transformation of epithelial tumor cells. Here, we show that upregulation of monoamine oxidase A (MAOA), a mitochondrial enzyme that degrades monoamine neurotransmitters and dietary amines, in stromal cells elevates production of reactive oxygen species, triggers an inflammatory response including activation of IL-6, and promotes tumorigenesis in vitro and in vivo. Mechanistically, MAOA enhances IL-6 transcription through direct Twist1 binding to a conserved E-box element at the IL-6 promoter. MAOA in stromal fibroblasts provides tumor cell growth advantages through paracrine IL-6/STAT3 signaling. Tissue microarray analysis revealed co-expression correlations between individual pairs of proteins of the stromal MAOA-induced Twist1/IL-6/STAT3 pathway in clinical specimens. Downstream of stromal MAOA, STAT3 also promotes cell stemness and transcriptionally activates expression of cancer stem cell marker CD44 in PC cells. MAOA inhibitor treatment effectively suppressed prostate tumor growth in mice in a stroma-specific targeted manner. Collectively, these findings characterize the contribution of MAOA to stromal activation in PC pathogenesis and provide a rationale for targeting MAOA in stromal cells to treat PC.

The differences of clinicopathologic characteristics among subgroups of reclassified HER2 fluorescence in situ hybridization (FISH) according to the ASCO/CAP 2018 breast cancer HER2 testing guidelines.

AIMS: The aim of this study is to analyse differences in clinicopathologic features among reclassified human epidermal growth factor receptor-2 (HER2) fluorescence in situ hybridization (FISH) results in breast cancers according to 2018 guidelines. METHODS: According to different ratios of HER2 copy numbers to chromosome 17 centromere numbers (HER2/CEP17) and average HER2 copy numbers, 3795 invasive breast cancers were classified into six groups. Clinicopathologic features were collected and compared among different FISH groups. RESULTS: There were no statistically significant differences about HER2 positive rate between 2013 and 2018 guidelines (p=0.518). After re-evaluating these cases according to 2018 guidelines, the cases that converted to a HER2 positive status had clinicopathologic features similar to samples in group 1 (ratio ≥2.0, HER2 ≥4.0). Compared with group 5 (ratio <2.0, HER2 <4.0), the cases in groups 1 had higher histological grade, more frequent occurrence of negative oestrogen receptor and progesterone receptor status and a higher Ki67 index. The samples in group 4 (ratio <2.0, 4.0≤HER2<6.0) showed a higher histological grade and higher Ki67 index than did the samples in group 5 but had a lower histological grade and lower Ki67 index than did the samples in group 1a (ratio ≥2.0, HER2 ≥6.0). CONCLUSION: Different categories of HER2 FISH test results have significant differences in clinicopathologic features. With no equivocal cases in 2018 HER2 guidelines, the clear division of HER2 status is helpful for making treatment recommendations about HER2 targeted therapy.

External quality assessment (EQA) program for the immunohistochemical detection of ER, PR and Ki-67 in breast cancer: results of an interlaboratory reproducibility ring study in China.

BACKGROUND: An External Quality Assessment (EQA) program was developed to investigate the status of estrogen receptor (ER), progesterone receptor (PR), and Ki-67 immunohistochemical (IHC) detection in breast cancer and to evaluate the reproducibility of staining and interpretation in 44 pathology laboratories in China. METHODS: This program was implemented through three specific steps. In study I, three revising centres defined the reference value for 11 sections. In study II, 41 participating centres (PC) stained and interpreted 11 sections by their own daily practice IHC protocols. In study III, all cases received second interpretation opinions. RESULTS: The stained slides of 44 laboratories were up to the interpretation standard. The overall interpretation concordance rate of this study was over 90%. A perfect agreement was reached among the PCs for the cases with ER+ and PR+ > 50% and Ki-67 > 30%, whereas a moderate agreement was observed for intermediate categories. After second interpretations, the misclassification rates for ER were reduced by 12.20%, for PR were reduced by 17.07%, and for Ki-67 were reduced by 4.88%. Up to 31 PCs observed a benefit from the second opinion strategy. CONCLUSIONS: This project is the first EQA study performed on a national scale for assessment of ER, PR and Ki-67 status by IHC in China. In the whole IHC evaluation process, the intermediate categories were less reproducible than those with high expression rates. Second opinions can significantly improve the diagnostic agreement of pathologists' interpretations.

Screening of Recurrence Related MicroRNA in Ductal Carcinoma In Situ and Functional Study of MicroRNA-654-5p.

PURPOSE: Ductal carcinoma in situ (DCIS) contributes to 20%-30% of newly diagnosed cases of breast cancer in China. Although the breast cancer-specific mortality of DCIS is extremely low, a small proportion of DCIS patients still show relapse or metastasis, leading to poor prognosis. Little is known about the molecular mechanism for DCIS metastasis, partly due to the limited number of poor prognosis patients. This study analyzed the clinicopathological features and screened key microRNAs (miRNAs) contributing to local or distant recurrence. METHODS: The clinicopathological features of DCIS were evaluated and survival analysis were performed to clarify risk factors associated with poor prognosis. Using miRNA arrays and real-time quantitative polymerase chain reaction (RT-qPCR) on DCIS formalin-fixed and paraffin-embedded samples with or without microinvasion with different clinical outcomes, potential DCIS metastasis-related miRNAs were screened out and further validated. The influence of one identified miRNA, miRNA-654-5p, on DCIS progression was analyzed. RESULTS: Poor prognosis was significantly associated with larger tumor size and higher lymph node metastasis rate (both p < 0.05). Both were independent prognostic factors for DCIS. According to RT-qPCR results, distinct miRNA expression profiles were identified between DCIS and DCIS with microinvasion (DCIS-Mi) patients. In the DCIS panel, miRNA-654-5p was significantly upregulated in the patients with poor prognosis. In vitro, miRNA-654-5p promoted MDA-MB-231 cell mobility in healing tests and metastasis in the Transwell study. CONCLUSION: The panel of high-risk miRNAs in DCIS and DCIS-Mi differs markedly. miRNA-654-5p is significantly upregulated DCIS patients having poor prognosis and may be essential for local and distant recurrence in DCIS.

Repression of miR-135b-5p promotes metastasis of early-stage breast cancer by regulating downstream target SDCBP.

Metastasis is an essential event for breast cancer (BC) progression even after initial surgery. The identification of patients with a high probability of metastasis at an early stage is particularly important in clinical practice and requires individualized treatment or early prevention. A retrospective study of 242 cases of ductal carcinoma in situ with microinvasion (DCIS-Mi), the first stage of invasive BC, was performed in this follow-up analysis. Of all patients, 8 developed metastases, and they were all included for further mechanistic studies with control group of 24 DCIS-Mi by matched-pair designing. By screening DCIS-Mi with different prognoses, we found that the DCIS-Mi that metastasized had significantly lower miR-135b-5p expression than the DCIS-Mi that did not. The function of miR-135b-5p was studied in vitro and in vivo invasion and metastasis assays. We also validated a novel target gene for miR-135b-5p, syndecan binding protein (SDCBP), and assessed the functional consequences of SDCBP by invasion assays. By checking different BC cell lines, a strong inverse correlation between miR-135b-5p and SDCBP expression was recorded. For the functional study, the inhibition of miR-135b-5p was accompanied by increased BC cell growth, epithelial-mesenchymal transition (EMT), migration and invasion in vitro. Interestingly, silencing SDCBP can reverse miR-135b-5p-dependent EMT and proliferation. In vivo studies demonstrated that the newly revealed miR-135b-5p/SDCBP axis increased cell proliferation, invasion and malignant transformation, as well as promoted metastasis in a xenograft tumor mouse model. Thus, our clinical patient cohort and functional data suggest that miR-135b-5p/SDCBP is a crucial determinant of BC metastasis at a very early stage. Our results may shed light on the importance of miR-135b-5p molecular diagnosis and prognosis, as well as the early prevention of BC for metastasis.

FGFR1 and HER1 or HER2 co-amplification in breast cancer indicate poor prognosis.

Human epidermal growth factor receptor 1 or 2 (HER1/2), and fibroblast growth factor receptor 1 (FGFR1) signaling serve critical roles in the progression of breast cancer; however, cross-talk between HER1/2 and FGFR1 signaling has not been extensively studied. In the present study, the copy number variation status of FGFR1 and HER1/2, and the clinical implications and prognostic relevance of this, were evaluated in invasive ductal breast cancer (IDC) tissue samples. Quantitative polymerase chain reaction and fluorescence in situ hybridization were used to assess gene copy number variation in IDC samples, and the clinical characteristics and survival curves of patients with IDC were analyzed. The amplification of FGFR1 was identified in 16.0% of the samples (12 of 75), of HER1 in 26.7% (20 of 75), of HER2 in 37.3% (28 of 75), and of FGFR1 and HER1/2 simultaneously in 8.0% (6 of 75). FGFR1 and HER1/2 co-amplification were significantly correlated with distant metastasis (P=0.035), recurrence (P=0.026) and decreased disease-free survival time (P=0.042). This was the case for patients undergoing endocrine therapy (P=0.002) and chemotherapy (P=0.044). Taken together, the results indicate that patients with FGFR1 and HER1/2 co-amplification may exhibit a less favorable prognosis compared with patients with either FGFR1, HER1/2 amplification or without amplification.

Clinical significance and prognostic value of receptor conversion in hormone receptor positive breast cancers after neoadjuvant chemotherapy.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is widely used in advanced breast cancer patients. However, there is little known about conversion frequency of estrogen receptor (ER) and/or progesterone receptor (PR) status for hormone receptor positive-breast cancer patients after NAC and their correlation with prognosis. METHODS: In this study, 231 breast cancer patients with residual disease after NAC were enrolled and divided into receptor stable group (having no conversion in both ER and PR status pre- and post-NAC) and any receptor conversion group (having any conversion in either ER or PR status). Univariate and multivariate survival analyses were used to compare survival differences between the two groups. RESULTS: Fifty-five patients (23.8%) had ER and/or PR conversion after NAC. Younger patients (≤ 50 years) were more likely to have receptor conversion (P = 0.014). For 213 patients (92.2%) who received adjuvant endocrinotherapy after surgery, the 5-year disease free survival (DFS) estimates for patients in the any receptor conversion group (55.2%) was worse than patients in the receptor stable group (73.7%, Log-rank test, P = 0.015). While the 5-year overall survival estimates for patients with or without receptor conversion were not statistically different (86.0 vs. 82.4%, Log-rank test, P = 0.587). In multivariate Cox proportional hazard analyses, patients with any receptor conversion had worse DFS (hazard ratio, 1.995; 95% confidence interval, 1.130-3.521, P = 0.031). CONCLUSIONS: It is necessary to recommend patients to test biomarkers in residual disease and pay more attention to patients who have any receptor conversion. These patients may need more individual therapy after surgery.

Long term prognosis of ductal carcinoma in situ with microinvasion: a retrospective cohort study.

Ductal carcinoma in situ with microinvasion (DCIS-Mi) is an early-stage breast cancer with long-term behavior, prognosis and treatment not fully understood. The aim of our study was to explore the clinicopathological and prognostic features of DCIS-Mi with pure DCIS and IDC-T1 (invasive ductal carcinoma with a tumor size ≤2 cm) as control. We retrospectively reviewed 242 cases of DCIS-Mi, 280 cases of pure DCIS, and 347 cases of IDC-T1. The clinicopathological features, therapeutic schemes and survival status were compared among the three groups. After a median follow-up of 109 months, the 5-year disease-free survival (DFS) was lower for the DCIS-Mi patients than for the DCIS patients but higher than the IDC-T1 patients (100%, 96.89% and 87.86% respectively, P<0.001). The 5-year breast cancer specific survival for DCIS-Mi patients was also between that of DCIS and IDC-T1 patients (100%, 99.32%, and 95.42% respectively, P=0.001). Tumor size (P<0.001, HR=18.31, 95% confidence interval (CI) 5.53-60.65) was identified as an independent prognostic factor for recurrence or metastasis. Furthermore, our study indicated that DCIS-Mi patients derived minimal, if any, benefit from chemotherapy treatment after mastectomy (P=0.63, HR=1.50, 95% CI 0.29-7.87). To our knowledge, this is the largest follow-up cohort study on Chinese DCIS-Mi patients. Our data suggested that DCIS-Mi exhibited worse clinical outcome than pure DCIS but better than that of IDC-T1. Tumor size was an independent prognostic factor. Post-mastectomy chemotherapy did not help for increasing DFS for DCIS-Mi patients.