R-loop-dependent promoter-proximal termination ensures genome stability.

The proper regulation of transcription is essential for maintaining genome integrity and executing other downstream cellular functions1,2. Here we identify a stable association between the genome-stability regulator sensor of single-stranded DNA (SOSS)3 and the transcription regulator Integrator-PP2A (INTAC)4-6. Through SSB1-mediated recognition of single-stranded DNA, SOSS-INTAC stimulates promoter-proximal termination of transcription and attenuates R-loops associated with paused RNA polymerase II to prevent R-loop-induced genome instability. SOSS-INTAC-dependent attenuation of R-loops is enhanced by the ability of SSB1 to form liquid-like condensates. Deletion of NABP2 (encoding SSB1) or introduction of cancer-associated mutations into its intrinsically disordered region leads to a pervasive accumulation of R-loops, highlighting a genome surveillance function of SOSS-INTAC that enables timely termination of transcription at promoters to constrain R-loop accumulation and ensure genome stability.

LINC00478-derived novel cytoplasmic lncRNA LacRNA stabilizes PHB2 and suppresses breast cancer metastasis via repressing MYC targets.

BACKGROUND: Metastasis is the predominant cause of mortality in patients with breast cancer. Long noncoding RNAs (lncRNAs) have been shown to drive important phenotypes in tumors, including invasion and metastasis. However, the lncRNAs involved in metastasis and their molecular and cellular mechanisms are still largely unknown. METHODS: The transcriptional and posttranscriptional processing of LINC00478-associated cytoplasmic RNA (LacRNA) was determined by RT-qPCR, semiquantitative PCR and 5'/3' RACE. Paired-guide CRISPR/cas9 and CRISPR/dead-Cas9 systems was used to knock out or activate the expression of LacRNA. Cell migration and invasion assay was performed to confirm the phenotype of LacRNA. Tail vein model and mammary fat pad model were used for in vivo study. The LacRNA-PHB2-cMyc axis were screened and validated by RNA pulldown, mass spectrometry, RNA immunoprecipitation and RNA-seq assays. RESULTS: Here, we identified a novel cytoplasmic lncRNA, LacRNA (LINC00478-associated cytoplasmic RNA), derived from nucleus-located lncRNA LINC00478. The nascent transcript of LINC00478 full-length (LINC00478_FL) was cleaved and polyadenylated, simultaneously yielding 5' ends stable expressing LacRNA, which is released into the cytoplasm, and long 3' ends of nuclear-retained lncRNA. LINC00478_3'RNA was rapidly degraded. LacRNA significantly inhibited breast cancer invasion and metastasis in vitro and in vivo. Mechanistically, LacRNA physically interacted with the PHB domain of PHB2 through its 61-140-nt region. This specific binding affected the formation of the autophagy degradation complex of PHB2 and LC3, delaying the degradation of the PHB2 protein. Unexpectedly, LacRNA specifically interacted with PHB2, recruited c-Myc and promoted c-Myc ubiquitination and degradation. The negatively regulation of Myc signaling ultimately inhibited breast cancer metastasis. Furthermore, LacRNA and LacRNA-mediated c-Myc signaling downregulation are significantly associated with good clinical outcomes, take advantage of these factors we constructed a prognostic predict model. CONCLUSION: Therefore, our findings propose LacRNA as a potential prognostic biomarker and a new therapeutic strategy.

MNX1 Promotes Anti-HER2 Therapy Sensitivity via Transcriptional Regulation of CD-M6PR in HER2-Positive Breast Cancer.

Although targeted therapy for human epidermal growth factor receptor 2 (HER2)-positive breast cancer has significantly prolonged survival time and improved patients' quality of life, drug resistance has gradually emerged. This study explored the mechanisms underlying the effect of the motor neuron and pancreatic homeobox 1 (MNX1) genes on drug sensitivity in HER2-positive breast cancer. From July 2017 to 2018, core needle biopsies of HER2-positive breast cancer were collected from patients who received paclitaxel, carboplatin, and trastuzumab neoadjuvant therapy at our center. Based on treatment efficacy, 81 patients were divided into pathological complete response (pCR) and non-pCR groups. High-throughput RNA sequencing results were analyzed along with the GSE181574 dataset. MNX1 was significantly upregulated in the pCR group compared with the non-pCR group in both sequencing datasets, suggesting that MNX1 might be correlated with drug sensitivity in HER2-positive breast cancer. Meanwhile, tissue array results revealed that high MNX1 expression corresponded to a good prognosis. In vitro functional tests showed that upregulation of MNX1 significantly increased the sensitivity of HER2-positive breast cancer cells to lapatinib and pyrotinib. In conclusion, MNX1 may serve as a prognostic marker for patients with HER2-positive breast cancer, and its expression may facilitate clinical screening of patients sensitive to anti-HER2-targeted therapy.

A nomogram for predicting axillary pathologic complete response in hormone receptor-positive breast cancer with cytologically proven axillary lymph node metastases.

BACKGROUND: The objective of this study was to determine an axillary pathologic complete response (pCR) and its influencing factors in patients with hormone receptor (HR)-positive breast cancer and cytologically proven axillary lymph node metastases. A prediction nomogram was established to provide information for the de-escalation of axillary management in these patients after neoadjuvant chemotherapy. METHODS: The authors retrospectively enrolled all patients with HR-positive breast cancer in the neoadjuvant chemotherapy data set of Fudan University Shanghai Cancer Center. All data were prospectively collected. From 2007 to 2016, 533 consecutive patients were included. Multivariate logistic regression analysis was performed, after which a nomogram was constructed and validated. RESULTS: An axillary pCR was achieved in 168 patients (31.5%), the which was much higher than the proportion of those who achieved a breast pCR (103 patients; 19.3%). Patients who had human epidermal growth factor receptor 2-positive disease (P = .004), a better primary tumor response (P = .001), earlier clinical stage (P = .045), and lower estrogen receptor expression (P < .001) were more likely to achieve a lymph node pCR. The nomogram indicated an area under the receiver operating characteristic curve (AUC) of 0.84 (95% CI, 0.78-0.89) in the training set. The validation set showed good discrimination with an AUC of 0.75 (95% CI, 0.69-0.81). The C-index was 0.834 and 0.756 in the training and validation cohort, respectively. The nomogram was well calibrated. CONCLUSIONS: The authors developed and validated a nomogram for predicting axillary pCR in patients with HR-positive disease accurately by using clinicopathologic factors available before surgery. The model will facilitate logical clinical decision making and clinical trial design.

Tumoral PD-1hiCD8+ T cells are partially exhausted and predict favorable outcome in triple-negative breast cancer.

Tumor-infiltrating PD-1hi dysfunctional CD8+ T cells have been identified in several tumors but largely unexplored in breast cancer (BC). Here we aimed to extensively explore PD-1hiCD8+ T cells in BC, focusing on the triple-negative BC (TNBC) subtype. Flow cytometry was used to study the phenotypes and functions of CD8+ T-cell subsets in peripheral blood and surgical specimens from treatment-naive BC patients. RNA-seq expression data generated to dissect the molecular features of tumoral PD-1neg, PD-1lo and PD-1hi CD8+ T cells. Further, the associations between tumoral PD-1hi CD8+ T cells and the clinicopathological features of 503 BC patients were explored. Finally, multiplexed immunohistochemistry (mIHC) was performed to evaluate in situ PD-1hiCD8+ T cells on the tissue microarrays (TMAs, n=328) for prognostic assessment and stratification of TNBC patients. PD-1hiCD8+ T cells found readily detectable in tumor tissues but rarely in peripheral blood. These cells shared the phenotypic and molecular features with exhausted and tissue-resident memory T cells (TRM) with a skewed TCR repertoire involvement. Interestingly, PD-1hiCD8+ T cells are in the state of exhaustion characterized by higher T-BET and reduced EOMES expression. PD-1hiCD8+ T cells found preferentially enriched within solid tumors, but predominant stromal infiltration of PD-1hiCD8+ T subset was associated with improved survival in TNBC patients. Taken together, tumoral PD-1hiCD8+ T-cell subpopulation in BC is partially exhausted, and their abundance signifies 'hot' immune status with favorable outcomes. Reinvigorating this population may provide further therapeutic opportunities in TNBC patients.

LINC02273 drives breast cancer metastasis by epigenetically increasing AGR2 transcription.

BACKGROUND: The majority of breast cancer patients die of metastasis rather than primary tumors, whereas the molecular mechanisms orchestrating cancer metastasis remains poorly understood. Long noncoding RNAs (lncRNA) have been shown to regulate cancer occurrence and progression. However, the lncRNAs that drive metastasis in cancer patients and their underlying mechanisms are still largely unknown. METHODS: lncRNAs highly expressed in metastatic lymph nodes were identified by microarray. Survival analysis were made by Kaplan-Meier method. Cell proliferation, migration, and invasion assay was performed to confirm the phenotype of LINC02273. Tail vein model and mammary fat pad model were used for in vivo study. RNA pull-down and RIP assay were used to confirm the interaction of hnRNPL and LINC02273. Chromatin isolation by RNA purification followed by sequencing (ChIRP-seq), RNA-seq, ChIP-seq, and luciferase reporter assay reveal hnRNPL-LINC02273 regulates AGR2. Antisense oligonucleotides were used for in vivo treatment. RESULTS: We identified a novel long noncoding RNA LINC02273, whose expression was significantly elevated in metastatic lesions compared to the primary tumors, by genetic screen of matched tumor samples. Increased LINC02273 promoted breast cancer metastasis in vitro and in vivo. We further showed that LINC02273 was stabilized by hnRNPL, a protein increased in metastatic lesions, in breast cancer cells. Mechanistically, hnRNPL-LINC02273 formed a complex which activated AGR2 transcription and promoted cancer metastasis. The recruitment of hnRNPL-LINC02273 complex to AGR2 promoter region epigenetically upregulated AGR2 by augmenting local H3K4me3 and H3K27ac levels. Combination of AGR2 and LINC02273 was an independent prognostic factor for predicting breast cancer patient survival. Moreover, our data revealed that LINC02273-targeting antisense oligonucleotides (ASO) substantially inhibited breast cancer metastasis in vivo. CONCLUSIONS: Our findings uncover a key role of LINC02273-hnRNPL-AGR2 axis in breast cancer metastasis and provide potential novel therapeutic targets for metastatic breast cancer intervention.

Increased Mortality with Repeat Lumpectomy Alone After Ipsilateral Breast Tumor Recurrence.

BACKGROUND: The benefit of repeat lumpectomy for ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery is currently inconclusive. MATERIALS AND METHODS: Patients with IBTR with definitive surgery were identified in the Surveillance, Epidemiology, and End Results registry between 1973 and 2013. The effect of different IBTR surgeries on overall and cancer-specific mortality was assessed using risk-adjusted Cox proportional hazard regression modeling and stratified propensity score-matching analysis (PSMA). RESULTS: Of the 5,098 patients with IBTR, 4,048 (79.4%) women underwent mastectomy and 1,050 (20.1%) underwent repeat lumpectomy. In multivariable Cox regression analysis, repeat lumpectomy was associated with increased overall mortality (hazard ratio for death [HR], 1.522; 95% confidence interval [CI], 1.317-1.759; p < .001) and cancer-specific mortality (HR, 1.666; 95% CI, 1.319-2.105; p < .001). Similar HRs were derived from the PSMA cohort. However, we found no significant difference in overall mortality for women who underwent repeat lumpectomy followed by radiation therapy (RT) compared with that for those who underwent mastectomy. Moreover, patients with IBTR with small tumors (≤1 cm) who underwent repeat lumpectomy with RT rather than without had similar overall and cancer-specific survival rates to those who underwent mastectomy. CONCLUSION: Our investigation suggests that compared with mastectomy, repeat lumpectomy for IBTR is associated with higher overall and cancer-specific mortality under real-world observational conditions. Furthermore, repeat lumpectomy with RT is equivalent to mastectomy with respect to overall mortality and may influence treatment decision making for patients with small IBTR. IMPLICATIONS FOR PRACTICE: Although mastectomy has been regarded as the standard treatment for ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery, many patients diagnosed with small and early-detected recurrent tumor might be technically suitable for a less invasive surgical procedure. However, different studies have drawn inconsistent conclusions. The present study is a population-based analysis, which demonstrated the overall unfavorable impact of repeat lumpectomy over mastectomy on survival outcomes for patients with IBTR. However, patients with small IBTR (≤1 cm) that can tolerate radiation therapy may be the optimal candidates for repeat lumpectomy.

High expression of Linc00959 predicts poor prognosis in breast cancer.

BACKGROUND: Accumulating studies have focused on the oncogenic roles of the newly identified lncRNAs in human cancers. The aim of this study was to examine the expression pattern of Linc00959 in BC and to evaluate its biological role and clinical significance in prediction of prognosis. METHODS: Expression of Linc00959 was detected in 290 BC tissues by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). We analyzed the relationship between Linc00959 expression and clinic pathological features of BC patients. The correlation was calculated by SPSS software. RESULTS: Our results revealed that Linc00959 expression was correlated with ER status (p = 0.005), PR status (p = 0.036), Ki67 (p = 0.025) and HER2 status (p = 0.009). The Kaplan-Meier survival curves indicated that the overall survival (OS) (p = 0.022) and relapse-free survival (RFS) (p = 0.002) were significantly poor in high Linc00959 expression BC patients (p = 0.023). Furthermore, the survival analysis by Cox regression showed that Linc00959 served as an independent prognostic marker in breast cancer (p = 0.004). CONCLUSION: Our studies indicate that Linc00959 is significantly associated with poor prognosis and may represent a new marker of prognosis in breast cancer.

LINC00309 is associated with short disease-free survival in breast cancer.

BACKGROUND: Long non-coding RNAs play an important role in breast cancer. Even with adjuvant hormone therapy, patients with estrogen receptor positive breast cancer can present with recurrences and distant metastases. We investigated whether the expression of a novel long non-coding RNA LINC00309 can predict the outcome of breast cancer, especially for hormone-receptor positive patients. METHODS: This retrospective study collected 290 breast cancer patients including 161 patients with hormone-positive. qPCR was performed to detect the expression of LINC00309. Kaplan-Meier and Cox risk proportion model were applied to disclose the function of LINC00309 for breast cancer prognosis. RESULTS: LINC00309 high expression was an independent predictor for worse disease-free survival (HR = 2.127; 95% CI 1.074-4.212; p = 0.030) and associated with a shorter disease-free survival (p = 0.027), especially in hormone-positive breast cancer patients (p = 0.001). Also LINC00309 high expression was associated with a shorter disease-free survival both in selective estrogen receptor modulator related hormone therapy (p = 0.025) and aromatase inhibitors related hormone therapy (p = 0.048). Moreover, LINC00309 was an independent predictor of worse disease-free survival in hormone-receptor positive breast cancer patients on univariate (HR = 4.505; 95% CI 1.722-11.785; p = 0.002) and multivariate (HR = 4.159; 95% CI 1.537-11.251; p = 0.005) analyses. CONCLUSION: In breast cancer, Linc00309 is significantly associated with poor prognosis and may represent a new marker of prognosis.

Changing patterns and survival improvements of young breast cancer in China and SEER database, 1999-2017.

OBJECTIVE: Breast cancer in young females was usually considered more aggressive and requires aggressive therapy. We investigated whether early detection and improved treatments changed the patterns of characteristics, management and outcomes of young breast cancer patients over time. METHODS: Females under 40 years of age diagnosed with breast cancer during the periods 1999-2017 and 1999-2015 were identified in the Fudan University Shanghai Cancer Center (FUSCC) and the population-based Surveillance, Epidemiology, and End Results (SEER) registry, respectively. Clinicopathologic characteristics and treatment information were collected. Patients diagnosed before 2013 were followed up. RESULTS: The proportions of young breast cancer patients were 15.0% and 5.3% in the FUSCC and SEER cohorts, respectively. In the FUSCC cohort, there was a significant increase in the proportion of ductal carcinoma in situ (DCIS) (from 8.8% to 16.9%; P<0.0001) and it remained stable in SEER cohort. The proportion of T1-stage tumors increased dramatically in the FUSCC cohort (from 35.3% to 41.9%; P=0.008), whereas it decreased in SEER cohort (from 42.4% to 33.0%; P<0.0001). The percentage of estrogen receptor (ER)-positive cancers was consistently increased in both the invasive ductal carcinoma (IDC) and DCIS patients in the two cohorts. Breast-conserving surgery and immediate implant reconstruction after mastectomy both exhibited increased use over time in the FUSCC cohort. Both the FUSCC and SEER cohorts showed a significantly better prognosis in the recent time period. CONCLUSIONS: With the increased early-stage and ER-positive diseases in young patients as well as better systemic treatment strategies, improved survival has been observed in recent years. There has been a substantial de-escalation in surgical therapies in young breast cancer patients.

Marital Status and Survival of Patients with Hormone Receptor-Positive Male Breast Cancer: A Surveillance, Epidemiology, and End Results (SEER) Population-Based Study.

BACKGROUND Although marital status has been reported as a prognostic factor in different cancer types, its prognostic effect on hormone receptor (HR) positive male breast cancer (MBC) is unclear. The objective of the present analysis was to assess the effects of marital status on survival in patients with HR positive MBC. MATERIAL AND METHODS Patients diagnosed with HR positive MBC from 1990 to 2014 in the Surveillance, Epidemiology, and End Results (SEER) database were included. Kaplan-Meier survival analysis and Cox proportional hazard regression were used to identify the effects of marital status on cancer-specific survival (CSS) and overall survival (OS). RESULTS A total of 3612 cases were identified in this study. Married patients had better 5-year CSS and 5-year OS than unmarried men. In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS and OS, independent of age, race, grade, stage, PR status, HER2 status, and surgery. Subgroup survival analysis according to different ER/PR status showed that married patients had beneficial CSS results only in ER+/PR+ subtype, and CSS in the married and unmarried groups did not significantly differ by TNM stage. The results were further confirmed in the 1: 1 matched group. CONCLUSIONS Marital status was an important prognostic factor for survival in patients with HR positive MBC. Unmarried patients are at greater risk of death compared with married groups. The survival benefit for married patients remained even after adjustment, which indicates the importance of spousal support in MBC.

DIXDC1 activates the Wnt signaling pathway and promotes gastric cancer cell invasion and metastasis.

DIXDC1 (Dishevelled-Axin domain containing 1) is a DIX (Dishevelled-Axin) domain-possessing protein that promotes colon cancer cell proliferation and increases the invasion and migration ability of non-small-cell lung cancer via the PI3K pathway. As a positive regulator of the Wnt/ß-catenin pathway, the biological role of DIXDC1 in human gastric cancer and the relationship between DIXDC1 and the Wnt pathway are unclear. In the current study, the upregulation of DIXDC1 was detected in gastric cancer and was associated with advanced TNM stage cancer, lymph node metastasis, and poor prognosis. We also found that the overexpression of DIXDC1 could promote the invasion and migration of gastric cancer cells. The upregulation of MMPs and the downregulation of E-cadherin were found to be involved in the process. DIXDC1 enhanced ß-catenin nuclear accumulation, which activated the Wnt pathway. Additionally, the inhibition of ß-catenin in DIXDC1-overexpressing cells reversed the metastasis promotion effects of DIXDC1. These results demonstrate that the expression of DIXDC1 is associated with poor prognosis of gastric cancer patients and that DIXDC1 promotes gastric cancer invasion and metastasis through the activation of the Wnt pathway; E-cadherin and MMPs are also involved in this process. © 2015 Wiley Periodicals, Inc.

Cyclin D3 predicts disease-free survival in breast cancer.

BACKGROUND: Cyclin D3, which induces progression through the G1 phase of the cell cycle, is a regulator of Cyclin-dependent kinases 4 and 6. Previous studies revealed that abnormal expression of Cyclin D3 was found in many different cancers. However, the role of Cyclin D3 in breast cancer (BC) remains unknown. The aim of this study is to examine the expression pattern of Cyclin D3 in BC and to evaluate its biological role and clinical significance in prognosis prediction. The mechanism involved is also evaluated. METHODS: Immunohistochemical staining was used to detect the expression of Cyclin D3. qRT-PCR was used to detect the mRNA level of Cyclin D3 in BC tissues and BC cell lines. Transwell assay was used to examine the role of Cyclin D3 in the migration and invasion of BC cells. Mass Spectrometry was used to search for the interacting protein with Cyclin D3. Co-Immunoprecipitation assay and GST-Pull Down assay were used to validate the interaction of Cyclin D3 and its interaction protein. RESULTS: Through detecting Cyclin D3 expression in 243 breast cancer patients' tissue array, we found Cyclin D3 expression was correlated with ER status (p = 0.000), PR status (p = 0.001), HER2 status (p = 0.002) and tumor differentiation (p = 0.045). The Kaplan-Meier survival curves indicated that the disease free survival (DFS) was significantly poor in high Cyclin D3 expression BC patients (p = 0.004). Furthermore, expression of Cyclin D3 was significantly associated with BC prognosis and was shown to be an independent prognostic marker in breast cancer (p = 0.028). By IHC staining and qPCR detection, Cyclin D3 expression was found to be down-regulated both in BC tissues and in BC cell lines compared with the corresponding normal controls. Further investigation showed Cyclin D3 was involved in the metastasis of BC cells and physically interacted with actin in vivo and in vitro. CONCLUSION: Our studies revealed that Cyclin D3 was upregulated in breast cancer and represented a novel predictor of BC prognosis.

Critical role of CDK11(p58) in human breast cancer growth and angiogenesis.

BACKGROUND: A capillary network is needed in cancer growth and metastasis. Induction of angiogenesis represents one of the major hallmarks of cancer. CDK11(p58), a Ser/Thr kinase that belongs to the Cell Division Cycle 2-like 1 (CDC2L1) subfamily is associated with cell cycle progression, tumorigenesis, sister chromatid cohesion and apoptotic signaling. However, its role in breast cancer proliferation and angiogenesis remains unclear. METHODS: Tumorigenicity assays and blood vessel assessment in athymic mice were used to assess the function of CDK11(p58) in tumor proliferation and angiogenesis. CCK-8 assay was used to detect breast cancer cell growth. Immunohistochemistry was used to detect the expression of vascular endothelial growth factor (VEGF), CD31 and CD34 in CDK11 positive patient breast cancer tissues. Dual-Luciferase array was used to analyze the function of CDK11(p58) in the regulation of VEGF promoter activity. Western blot was used to detect related protein expression levels. RESULTS: CDK11(p58) inhibited breast cancer growth and angiogenesis in breast cancer cells and in nude mice transplanted with tumors. Immunohistochemistry confirmed that CDK11(p58) was negatively associated with angiogenesis-related proteins such as VEGF, CD31 and CD34 in breast cancer patients. Real-time PCR and dual-luciferase assay showed CDK11(p58) inhibited the mRNA levels of VEGF and the promoter activity of VEGF. As CDK11(p58) is a Ser/Thr kinase, the kinase-dead mutant failed to inhibit VEGF mRNA and promoter activity. Western blot analysis showed the same pattern of related protein expression. The data suggested angiogenesis inhibition was dependent on CDK11(p58) kinase activity. CONCLUSION: This study indicates that CDK11(p58) inhibits the growth and angiogenesis of breast cancer dependent on its kinase activity.

Abnormal expression of CDK11p58 in prostate cancer.

BACKGROUND: CDK11p58 is one of the large families of p34cdc2-related kinases whose functions are linked with cell cycle progression, tumorigenesis and apoptotic signaling. Our previous investigation demonstrated that CDK11p58 repressed androgen receptor (AR) transcriptional activity and was involved in the negative regulation of AR function. METHODS: CDK11p58 expression was examined in the prostate cancer tissues and adjacent tissues by IHC and qRT-PCR. Cell apoptosis was detected by flow cytometry. The metastasis of cancer cells was evaluated by the Transwell Assay. Finally we further investigated the underlying molecular mechanisms by examining expression levels of relevant proteins using western blot analysis. RESULTS: We found that both RNA and protein expression of CDK11p58 were low in prostate cancer tissues compared with its adjacent noncancerous tissues. CDK11p58 promoted the prostate cancer cell apoptosis and inhibited its metastasis in a kinase dependent way. And finally CDK11p58 could inhibit the metastasis of AR positive prostate cancer cells through inhibition of integrin ß3 and MMP2. CONCLUSIONS: These data indicate that CDK11p58 is an anti-metastasis gene product in prostate cancer.

Role of BC040587 as a predictor of poor outcome in breast cancer.

BACKGROUND: Accumulating studies have focused on the oncogenic and tumor suppressive roles of the newly identified lncRNAs. A novel lncRNA BC040587 in 3q13.31 locus which exists frequent copy number alterations was found to be associated with poor survival of osteosarcoma patients. However, its role in breast cancer (BC) remains unknown. The aim of this study was to examine the expression pattern of BC040587 in BC and to evaluate its biological role and clinical significance in prediction of prognosis. METHODS: Expression of BC040587 was analyzed in 20 pairs of BC cancer tissues and adjacent noncancerous tissues (ANCT), also in 151 BC tissues, 9 BC cell lines and one normal breast cell line by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Differences between groups were tested for significance using Student's t-test (two-tailed). Then we analyzed the potential relationship between BC040587 expression and clinic pathological features of BC patients. The correlation was analyzed by SPSS software. RESULTS: It showed that BC040587 expression was down regulated both in BC samples and in BC cell lines compared with corresponding normal control. BC040587 expression was correlated with menopausal status (p = 0.040) and tumor differentiation (p = 0.035). The Kaplan-Meier survival curves indicated that the overall survival (OS) was significantly poor in low BC040587 expression BC patients (p = 0.023). Furthermore, expression of BC040587 was significantly associated with worse prognosis and was shown to be an independent prognostic marker breast cancer (p = 0.032). Our studies indicate that BC040587 may represent a new marker of prognosis in breast cancer. CONCLUSION: Our studies indicate that BC040587 is significantly down-regulated in BC tissues and BC cell lines. BC040587 may represent a new marker of prognosis in breast cancer.

CDK11p58 inhibits ERα-positive breast cancer invasion by targeting integrin ß3 via the repression of ERα signaling.

BACKGROUND: CDK11(p58), a Ser/Thr kinase that belongs to the cell division cycle 2-like 1 (CDC2L1) subfamily, is associated with cell cycle progression, tumorigenesis and apoptotic signaling. CDK11(p58) is also involved in the regulation of steroid receptors, such as androgen and estrogen receptors. We previously found that CDK11(p58) was abnormally expressed in prostate cancer. However, its role in breast cancer remains unclear. METHODS: CDK11(p58) expression was evaluated by immunohistochemical staining in a tissue array. A Transwell assay was used to detect invasion and metastasis in breast cancer cells. The TaqMan® Metastasis Gene Expression Assay was used to search for potential downstream factors in the CDK11(p58) signaling pathway. qRT-PCR was used to evaluate mRNA levels, and the dual luciferase array was used to analyze promoter activity. Western blotting was used to detect the protein level. RESULTS: CDK11(p58) expression was negatively correlated with node status (P = 0.012), relapse status (P = 0.002) and metastasis status (P = 0.023). Kaplan-Meier survival curves indicated that the disease-free survival (DFS) was significantly poor in breast cancer patients with low CDK11 expression. Interestingly, using the breast cancer cell lines ZR-75-30 and MDA-MB-231, we found that CDK11(p58) was capable of repressing the migration and invasion of ERα-positive breast cancer cells, but not ERα-negative breast cancer cells, in a kinase-dependent manner. Gene expression assays demonstrated that integrin ß3 mRNA was dramatically repressed by CDK11(p58), and luciferase results confirmed that the integrin ß3 promoter was inhibited by CDK11(p58) through ERα repression. The expression of integrin ß3 was highly related to ERα signaling; ERα overexpression stimulated integrin ß3 expression, whereas siRNA-mediated knockdown of ERα attenuated integrin ß3 expression. CONCLUSIONS: These data indicate that CDK11(p58) is an anti-metastatic gene in ERα-positive breast cancer and that the regulation of integrin ß3 by CDK11(p58) via the repression of ERα signaling may constitute part of a signaling pathway underlying breast cancer invasion.

Identification of chromosomal copy number variations and novel candidate loci in hereditary nonpolyposis colorectal cancer with mismatch repair proficiency.

The pathogenesis of microsatellite stable hereditary non-polyposis colorectal cancers (MSS HNPCC) is unclear. To identify genomic regions that might be involved in MSS HNPCC pathogenesis, we selected 20 pairs of MSS HNPCC for a genome-wide study using copy number variation targeted (CNV-targeted) CytoScan HD Array. A remarkably increased frequency of 20q gain (70%) and high levels of copy-neutral loss of heterozygosity (40%) were observed. The most frequent tumor-specific CNVs included amplifications (7p21.3-15.1, 8q13.3-24.3, 13q14.1-33.3 and 20q12-13.33) and deletions (8p11.23-23.1, 15q11.2-26.1, 17p13.1-13.3 and 18q11.2-21.33). In addition, 10 novel CNVs were discovered and led to identification of WDR16 and RAPGEF5 as candidate genes involved in tumorigenesis, displaying a robust correlation between expression and genomic alterations. Moreover, WDR16 and RAPGEF5 exhibited altered protein expression levels as assessed by immunohistochemistry (IHC) in 41 other independent samples. Finally, high consistencies (68-84%) were observed between CNVs by Array and quantitative PCR. These findings are important for further elucidating MSS HNPCC pathogenesis.

CRTAM promotes antitumor immune response in triple negative breast cancer by enhancing CD8+ T cell infiltration.

The immunomodulatory (IM) subtype of triple negative breast cancer (TNBC) exhibits high expression of immune cell signaling genes and is more responsive to immunotherapy. However, the specific mechanism underlying this phenomenon remains unclear. One of the potential key genes appears to be the cytotoxic and regulatory T cell molecule (CRTAM). A cohort of 360 previously untreated TNBC patients from Fudan University Shanghai Cancer Center (FUSCC) underwent RNA sequencing analysis of their primary tumor tissue. Combined with three RNA-seq datasets obtained from the GEO database, a LASSO regression analysis was conducted to identify genes specific to the IM type of TNBC. Our findings revealed elevated CRTAM expression in the IM-type TNBC, which correlated with a favorable overall survival and recurrence-free survival in TNBC patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated a strong association between CRTAM and immune responses as well as immune system processes. Notably, CRTAM overexpression induced STAT1 phosphorylation and upregulation of interferon-stimulated genes. We also found that CRTAM enhanced tumor-associated immune cell infiltration, especially CD8+ T cells, which may be related to the increased expression of MHC class I molecules caused by CRTAM overexpression. These results suggest that CRTAM may serve as a potential biomarker for predicting the efficacy of immunotherapy in TNBC.

DUSP4 enhances therapeutic sensitivity in HER2-positive breast cancer by inhibiting the G6PD pathway and ROS metabolism by interacting with ALDOB.

BACKGROUND: Breast cancer (BC) poses a global threat, with HER2-positive BC being a particularly hazardous subtype. Despite the promise shown by neoadjuvant therapy (NAT) in improving prognosis, resistance in HER2-positive BC persists despite emerging targeted therapies. The objective of this study is to identify markers that promote therapeutic sensitivity and unravel the underlying mechanisms. METHODS: We conducted an analysis of 86 HER2-positive BC biopsy samples pre-NAT using RNA-seq. Validation was carried out using TCGA, Kaplan‒Meier Plotter, and Oncomine databases. Phenotype verification utilized IC50 assays, and prognostic validation involved IHC on tissue microarrays. RNA-seq was performed on wild-type/DUSP4-KO cells, while RT‒qPCR assessed ROS pathway regulation. Mechanistic insights were obtained through IP and MS assays. RESULTS: Our findings reveal that DUSP4 enhances therapeutic efficacy in HER2-positive BC by inhibiting the ROS pathway. Elevated DUSP4 levels correlate with increased sensitivity to HER2-targeted therapies and improved clinical outcomes. DUSP4 independently predicts disease-free survival (DFS) and overall survival (OS) in HER2-positive BC. Moreover, DUSP4 hinders G6PD activity via ALDOB dephosphorylation, with a noteworthy association with heightened ROS levels. CONCLUSIONS: In summary, our study unveils a metabolic reprogramming paradigm in BC, highlighting DUSP4's role in enhancing therapeutic sensitivity in HER2-positive BC cells. DUSP4 interacts with ALDOB, inhibiting G6PD activity and the ROS pathway, establishing it as an independent prognostic predictor for HER2-positive BC patients.