LAPTM4B Allele *2 Is a Marker of Poor Prognosis for Gallbladder Carcinoma

Background

Lysosomal protein transmembrane 4 beta (LAPTM4B) is a novel cancer-related gene which has two alleles designated LAPTM4B*1 and LAPTM4B*2. In this study we investigated the correlation of LAPTM4B genotype with prognosis and clinicopathologic features in patients who had undergone curative resection for gallbladder carcinoma (GBC).

Methodology/Principal Findings

PCR assay was performed to determine the LAPTM4B genotype in 85 patients. The correlation of LAPTM4B genotype with clinicopathologic parameters was assessed with the Chi-squared test. Differences in patient survival were determined by the Kaplan–Meier method. Multivariate analysis of prognostic factors was carried out with Cox regression analysis. Patients with LAPTM4B *2 had both significantly shorter overall survival (OS) and shorter disease-free survival (DFS) (both P<0.001). Multivariate analysis showed that LAPTM4B genotype is a prognostic factor for OS and DFS (both P<0.001).

Conclusions/Significance

LAPTM4B allele *2 is a risk factor associated with poor prognosis in patients with resected GBC, and LAPTM4B status may be therefore be useful preoperatively as an adjunct in evaluation of the operability of GBC.     

LAPTM4B-35, a Cancer-Related Gene,Is Associated with Poor Prognosis in TNM Stages I-III Gastric Cancer Patients

Background

Lysosome-associated transmembrane protein 4β-35 (LAPTM4B-35), a member of the mammalian 4-tetratransmembrane spanning protein superfamily, has been reported to be overexpressed in several cancers. However the expression of LAPTM4B-35 and its role in the progression of gastric cancer (GC) remains unknown. The aim of this study was to investigate LAPTM4B-35 expression in GC, its potential relevance to clinicopathologic parameters and role of LAPTM4B-35 during gastric carcinogenesis.

Methods

In the present study, paraffin-embedded specimens with GC (n = 240, including 180 paired specimens) and 24 paired fresh frozen tissues were analyzed. qRT-PCR and immunohistochemistry (IHC) were used to analyze the expression of LAPTM4B-35 in GC. The effects of LAPTM4B-35 on GC cell proliferation, migration and invasion were determined by overexpression and knockdown assays.

Results

IHC showed that LAPTM4B-35 was expressed in 68.3% (123/180) of GC tissues, while in 16.1% (29/180) of their paired adjacent noncancerous gastric tissues (P = 0.000). LAPTM4B-35 mRNA levels in GC tissues were also significantly elevated when compared with their paired adjacent noncancerous tissues (P = 0.017). Overexpression of LAPTM4B-35 was significantly associated with degree of differentiation, depth of invasion, lymphovascular invasion and lymph node metastasis (P<0.05). Kaplan-Meier survival curves revealed that patients with LAPTM4B-35 expression had a significant decrease in overall survival (OS) in stages I-III GC patients (P = 0.006). Multivariate analysis showed high expression of LAPTM4B-35 was an independent prognostic factor for OS in stage I-III GC patients (P = 0.025).

Conclusion

These findings indicate that LAPTM4B-35 overexpression may be related to GC progression and poor prognosis, and thus may serve as a new prediction marker of prognosis in GC patients.     

High Bak Expression Is Associated with a Favorable Prognosis in Breast Cancer and Sensitizes Breast Cancer Cells to Paclitaxel

Breast cancer has become the leading cause of cancer-related death among women. A large number of patients become resistant to drug chemotherapy. Paclitaxel (Taxol) is an effective chemotherapeutic agent used to treat cancer patients. Taxol has been widely used in human malignancies including breast cancer because it can stabilize microtubules resulting in cell death by causing an arrest during the G2/M phase of the cell cycle. Pro-apoptotic Bcl-2 antagonist killer 1 (Bak) plays an important role in Taxol-induced apoptosis in breast cancer. In our present study, we investigated the expression of the Bak protein and clinicopathological correlations in a large sample of breast cancer tissues by immunohistochemistry. We found that the percentage of high scores of Bak expression in breast cancer was significantly lower than that of the non-cancerous breast control tissue. In addition, lower Bak expression was positively associated with the clinical TNM stage of breast cancer with a significant decrease in overall survival compared with those with higher Bak expression especially in the Luminal and HER2 subtypes. Importantly, higher Bak expression predicted a favorable clinical outcome in the cases treated with Taxol indicated by a higher overall survival than that of patients with lower Bak expression especially in Luminal and HER2 subtypes. Furthermore, these results were confirmed in vitro since overexpression of Bak sensitized breast cancer cells to Taxol by inhibiting proliferation and promoting apoptosis; in contrast, downregulation of Bak through siRNA transfection inhibited Taxol induced-apoptosis. Therefore, our results demonstrate that Bak acts as a sensitive biomarker and favorable prognostic factor for Taxol treatment in breast cancer. The restoration of Bak expression would be therapeutically beneficial for Taxol resistant breast cancer patients.     

CD24 Overexpression Is Associated with Poor Prognosis in Luminal A and Triple-Negative Breast Cancer

CD24 is associated with unfavourable prognoses in various cancers, but the prevalence of CD24 expression and its influence on clinical outcome in subtypes of breast cancers remain unclear. CD24 expression was analyzed by immunohistochemistry in 747 breast cancer tissues, and DNA methylation and histone modification status in the promoter region of CD24 were assessed using bisulfite sequencing and chromatin immunoprecipitation assay. 213 (28.5%) samples exhibited high CD24 expression in the membrane and/or cytoplasm of breast cancer cells, and CD24 overexpression was significantly correlated with the presence of lymph node metastasis and more advanced pathological stage. Patients with CD24-high tumours had significantly shorter patient survival than those with CD24-low tumours. Importantly, multivariate analysis that included tumour size, lymph node metastasis and chemotherapy demonstrated that high CD24 expression is independently associated with poorer survival in luminal A and triple-negative breast cancer (TNBC) subtypes. Furthermore, CD24 gene expression was associated with histone acetylation independent of DNA methylation, suggesting its epigenetic regulation in breast cancer. Our results suggest that CD24 overexpression is an independent unfavourable prognostic factor in breast cancer, especially for luminal A and TNBC subtypes, and CD24 may be a promising therapeutic target for specific subtypes of breast cancer.     

Microbial Dysbiosis Is Associated with Human Breast Cancer

Breast cancer affects one in eight women in their lifetime. Though diet, age and genetic predisposition are established risk factors, the majority of breast cancers have unknown etiology. The human microbiota refers to the collection of microbes inhabiting the human body. Imbalance in microbial communities, or microbial dysbiosis, has been implicated in various human diseases including obesity, diabetes, and colon cancer. Therefore, we investigated the potential role of microbiota in breast cancer by next-generation sequencing using breast tumor tissue and paired normal adjacent tissue from the same patient. In a qualitative survey of the breast microbiota DNA, we found that the bacterium Methylobacterium radiotolerans is relatively enriched in tumor tissue, while the bacterium Sphingomonas yanoikuyae is relatively enriched in paired normal tissue. The relative abundances of these two bacterial species were inversely correlated in paired normal breast tissue but not in tumor tissue, indicating that dysbiosis is associated with breast cancer. Furthermore, the total bacterial DNA load was reduced in tumor versus paired normal and healthy breast tissue as determined by quantitative PCR. Interestingly, bacterial DNA load correlated inversely with advanced disease, a finding that could have broad implications in diagnosis and staging of breast cancer. Lastly, we observed lower basal levels of antibacterial response gene expression in tumor versus healthy breast tissue. Taken together, these data indicate that microbial DNA is present in the breast and that bacteria or their components may influence the local immune microenvironment. Our findings suggest a previously unrecognized link between dysbiosis and breast cancer which has potential diagnostic and therapeutic implications.     

The GADD45A (1506T>C) Polymorphism Is Associated with Ovarian Cancer Susceptibility and Prognosis

GADD45A (growth arrest and DNA damage 45 A) is the first stress-inducible gene identified to be a target of p53. However, no studies to date have assessed variants of the GADD45 gene and their potential relationship to tumor susceptibility. We investigated the association of the GADD45A (1506T>C) polymorphism with ovarian cancer development in 258 ovarian cancer patients and 332 age-matched healthy women as controls using sequence analysis. We found a statistically significant difference in the GADD45A (1506T>C) genotype distributions between the case and control groups (TT vs. TC vs. CC, P = 0.0021) and found that variant 1506T>C was significantly associated with an increased risk of ovarian cancer (P<0.001, OR = 1.71, 95% CI [1.28–2.29]). We observed a statistically significant effect between tumor histology (P = 0.032) and CA125 status (P = 0.021). Carrying the C allele (TC+CC) was associated with an increased risk of positive CA125 (OR = 3.20, 95% CI [1.15–8.71). Carrying the T allele (TT+TC) showed a significant correlation with both higher GADD45A mRNA expression and longer ovarian cancer RFS (relapse-free survival) and OS (overall survival). We are the first group to demonstrate that the GADD45A (1506T>C) polymorphism is associated with ovarian cancer susceptibility and prognosis. These data suggest that GADD45A (1506T>C) is a new tumor susceptibility gene and could be a useful molecular marker for assessing ovarian cancer risk and for predicting ovarian cancer patient prognosis.     

LSD1 Overexpression Is Associated with Poor Prognosis in Basal-Like Breast Cancer,and Sensitivity to PARP Inhibition

LSD1, a lysine-specific histone demethylase, is overexpressed in several types of cancers and linked to poor outcomes. In breast cancer, the significance of LSD1 overexpression is not clear. We have performed an in silico analysis to assess the relationship of LSD1 expression to clinical outcome. We demonstrate that LSD1 overexpression is a poor prognostic factor in breast cancer, especially in basal-like breast cancer, a subtype of breast cancer with aggressive clinical features. This link is also observed in samples of triple negative breast cancer. Interestingly, we note that overexpression of LSD1 correlates with down-regulation of BRCA1 in triple negative breast cancer. This phenomenon is also observed in in vitro models of basal-like breast cancer, and is associated with an increased sensitivity to PARP inhibitors. We propose therefore that high expression levels of the demethylase LSD1 is a potential prognostic factor of poor outcome in basal-like breast cancer, and that PARP inhibition may be a therapeutic strategy of interest in this poor prognostic subtype with overexpression of LSD1.     

Evidence That Breast Tissue Stiffness Is Associated with Risk of Breast Cancer

Background

Evidence from animal models shows that tissue stiffness increases the invasion and progression of cancers, including mammary cancer. We here use measurements of the volume and the projected area of the compressed breast during mammography to derive estimates of breast tissue stiffness and examine the relationship of stiffness to risk of breast cancer.

Methods

Mammograms were used to measure the volume and projected areas of total and radiologically dense breast tissue in the unaffected breasts of 362 women with newly diagnosed breast cancer (cases) and 656 women of the same age who did not have breast cancer (controls). Measures of breast tissue volume and the projected area of the compressed breast during mammography were used to calculate the deformation of the breast during compression and, with the recorded compression force, to estimate the stiffness of breast tissue. Stiffness was compared in cases and controls, and associations with breast cancer risk examined after adjustment for other risk factors.

Results

After adjustment for percent mammographic density by area measurements, and other risk factors, our estimate of breast tissue stiffness was significantly associated with breast cancer (odds ratio = 1.21, 95% confidence interval = 1.03, 1.43, p = 0.02) and improved breast cancer risk prediction in models with percent mammographic density, by both area and volume measurements.

Conclusion

An estimate of breast tissue stiffness was associated with breast cancer risk and improved risk prediction based on mammographic measures and other risk factors. Stiffness may provide an additional mechanism by which breast tissue composition is associated with risk of breast cancer and merits examination using more direct methods of measurement.     

Mitochondrial DNA Copy Number Is Associated with Breast Cancer Risk

Mitochondrial DNA (mtDNA) copy number in peripheral blood is associated with increased risk of several cancers. However, data from prospective studies on mtDNA copy number and breast cancer risk are lacking. We evaluated the association between mtDNA copy number in peripheral blood and breast cancer risk in a nested case-control study of 183 breast cancer cases with pre-diagnostic blood samples and 529 individually matched controls among participants of the Singapore Chinese Health Study. The mtDNA copy number was measured using real time PCR. Conditional logistic regression analyses showed that there was an overall positive association between mtDNA copy number and breast cancer risk (P_trend = 0.01). The elevated risk for higher mtDNA copy numbers was primarily seen for women with <3 years between blood draw and cancer diagnosis; ORs (95% CIs) for 2^nd, 3^rd, 4^th, and 5^th quintile of mtDNA copy number were 1.52 (0.61, 3.82), 2.52 (1.03, 6.12), 3.12 (1.31, 7.43), and 3.06 (1.25, 7.47), respectively, compared with the 1^st quintile (P_trend = 0.004). There was no association between mtDNA copy number and breast cancer risk among women who donated a blood sample ≥3 years before breast cancer diagnosis (P_trend = 0.41). This study supports a prospective association between increased mtDNA copy number and breast cancer risk that is dependent on the time interval between blood collection and breast cancer diagnosis. Future studies are warranted to confirm these findings and to elucidate the biological role of mtDNA copy number in breast cancer risk.     

MRI Background Parenchymal Enhancement Is Not Associated with Breast Cancer

BackgroundPreviously, a strong positive association between background parenchymal enhancement (BPE) at magnetic resonance imaging (MRI) and breast cancer was reported in high-risk populations. We sought to determine, whether this was also true for non-high-risk patients.Methods540 consecutive patients underwent breast MRI for assessment of breast findings (BI-RADS 0–5, non-high-risk screening (no familial history of breast cancer, no known genetic mutation, no prior chest irradiation, or previous breast cancer diagnosis)) and subsequent histological work-up. For this IRB-approved study, BPE and fibroglandular tissue FGT were retrospectively assessed by two experienced radiologists according to the BI-RADS lexicon. Pearson correlation coefficients were calculated to explore associations between BPE, FGT, age and final diagnosis of breast cancer. Subsequently, multivariate logistic regression analysis, considering covariate colinearities, was performed, using final diagnosis as the target variable and BPE, FGT and age as covariates.ResultsAge showed a moderate negative correlation with FGT (r = -0.43, p<0.001) and a weak negative correlation with BPE (r = -0.28, p<0.001). FGT and BPE correlated moderately (r = 0.35, p<0.001). Final diagnosis of breast cancer displayed very weak negative correlations with FGT (r = -0.09, p = 0.046) and BPE (r = -0.156, p<0.001) and weak positive correlation with age (r = 0.353, p<0.001). On multivariate logistic regression analysis, the only independent covariate for prediction of breast cancer was age (OR 1.032, p<0.001).ConclusionsBased on our data, neither BPE nor FGT independently correlate with breast cancer risk in non-high-risk patients at MRI. Our model retained only age as an independent risk factor for breast cancer in this setting.     

Cytoplasmic Skp2 Expression Is Associated with p-Akt1 and Predicts Poor Prognosis in Human Breast Carcinomas

Background

S-phase kinase protein 2 (Skp2), an oncogenic protein, is a key regulator in different cellular and molecular processes, through ubiquitin-proteasome degradation pathway. Increased levels of Skp2 are observed in various types of cancer and associated with poor prognosis. However, in human breast carcinomas, the underlying mechanism and prognostic significance of cytoplasmic Skp2 is still undefined.

Methods

To investigate the role of cytoplasmic Skp2 expression in human breast carcinomas, we immnohistochemically assessed cytoplasmic Skp2, p-Akt1, and p27 expression in 251 patients with invasive ductal carcinomas of the breast. Association of cytoplasmic Skp2 expression with p-Akt1 and p27 was analyzed as well as correspondence with other clinicopathological parameters. Disease-free survival and overall survival were determined based on the Kaplan-Meier method and Cox regression models.

Results

Cytoplasmic of Skp2 was detected in 165 out of 251 (65.7%) patients. Cytoplasmic Skp2 expression was associated with larger tumor size, more advanced histological grade, and positive HER2 expression. Increased cytoplasmic Skp2 expression correlated with p-Akt1 expression, with 54.2% (51/94) of low p-Akt1-expressing breast carcinomas, but 72.6% (114/157) of high p-Akt1-expressing breast carcinomas exhibiting cytoplasmic Skp2 expression. Elevated cytoplasmic Skp2 expression with low p-Akt1 expression was associated with poor disease-free and overall survival (DFS and OS), and Cox regression models demonstrated that cytoplasmic Skp2 expression was an independent prognostic marker for invasive breast carcinomas.

Conclusion

Cytoplasmic Skp2 expression is associated with aggressive prognostic factors, such as larger tumor size, and advanced histological grade of the breast cancers. Results demonstrate that combined cytoplasmic Skp2 and p-Akt1 expression may be prognostic for patients with invasive breast carcinomas, and cytoplasmic Skp2 may serve as a potential therapeutic target.     

Screening Preeclamptic Cord Plasma for Proteins Associated with Decreased Breast Cancer Susceptibility

Preeclampsia, a complication of pregnancy characterized by hypertension and proteinuria, has been found to reduce the subsequent risk for breast cancer in female offspring. As this pro- tective effect could be due to exposure to preeclampsia-specific proteins during intrauterine life, the proteomic profiles of umbilical cord blood plasma between preeclamptic and normotensive pregnancies were compared. Umbilical cord plasma samples, depleted of 14 abundant proteins, were subjected to proteomic analysis using the quantitative method of nanoACQUITY ultra performance liquid chromatography-mass spectrometry with elevated energy mode of acquisitionE （NanoUPLC-MSE）. Sixty-nine differentially expressed proteins were identified, of which 15 and 6 proteins were only detected in preeclamptic and normotensive pregnancies, respectively.Additionally, expression of 8 proteins （gelsolin, complement C5, keratin type I cytoskeletal 10, pigment epithelium-derived factor, complement factor B, complement component C7, hemoglobin subunit gamma-2 and alpha-fetoprotein） were up-regulated in preeclampsia with a fold change of 1〉 2.0 when compared to normotensive pregnancies. The identification of alpha-fetoprotein in pre- eclamptic umbilical cord blood plasma supported the validity of this screen as alpha-fetoprotein has anti-estrogenic properties and has previously been linked to preeclampsia as well as a reduced breast cancer risk. The findings of this pilot study may provide new insights into the mechanistic link between preeclampsia and potentially reduced breast cancer susceptibility in adult life.     

Relationship Between LAPTM4B Gene Polymorphism and Susceptibility of Malignant Melanoma in Chinese Patients

Lysosomal-associated protein transmembrane 4 beta (LAPTM4B) is known as an oncogene associated with many human malignant tumors. There are two alleles of the gene, LAPTM4B*1 and LAPTM4B*2. Previous studies have shown that LAPTM4B polymorphism contributes to the risk of many cancers. This case-control study was to investigate the relationship between LAPTM4B gene polymorphism and susceptibility of malignant melanoma. The genotypes of LAPTM4B were determined in 617 control subjects and 220 patients with malignant melanoma by utilizing polymerase chain reaction based on specific primers. The genotypic distribution of LAPTM4B and Hardy–Weinberg equilibrium were analyzed by χ² test. Odds ratio and 95% confidence interval was calculated by unconditional logistic regression. The distributions of LAPTM4B genotypes were significantly different between melanoma patients (45.9% for *1/1, 46.4% for *1/2 and 7.7 for *2/2) and controls (54.5% for *1/1, 39.9% for *1/2 and 5.7 for *2/2). LAPTM4B *1/2 and LAPTM4B *2/2 had a 1.396-fold and 1.619-fold higher risk for melanoma occurrence than *1/1, and subjects with LAPTM4B*2 have a 1.308-fold higher risk than LAPTM4B*1 carriers. No association between LAPTM4B genotypes and gender, age, subtype, Clark level of invasion, Breslow thickness, ulceration, clinical stage, and C-KIT, BRAF gene mutation status was observed. LAPTM4B*2 is associated with the high risk of malignant melanoma and carrying LAPTM4B *2 may be a susceptible factor to Chinese melanoma patients.     

Expression of Sirtuin 1 and 2 Is Associated with Poor Prognosis in Non-Small Cell Lung Cancer Patients

Background

Sirtuin 1 (SIRT1) and sirtuin 2 (SIRT2) are NAD+-dependent protein deacetylases involved in the regulation of key cancer-associated genes. In this study we evaluated the relevance of these deacetylases in lung cancer biology.

Material and Methods

Protein levels of SIRT1 and SIRT2 were determined in non-small cell lung cancer (NSCLC) cell lines and primary tumors from 105 patients. Changes in proliferation were assessed after SIRT1 and SIRT2 downregulation in lung cancer cell lines using siRNA-mediated technology or tenovin-1, a SIRT1 and SIRT2 inhibitor.

Results

High SIRT1 and SIRT2 protein levels were found in NSCLC cell lines compared with non-tumor lung epithelial cells. The expression of SIRT1 and SIRT2 proteins was also significantly higher in lung primary tumors than in normal tissue (P<0.001 for both sirtuins). Stronger nuclear SIRT1 staining was observed in adenocarcinomas than in squamous cell carcinomas (P=0.033). Interestingly, in NSCLC patients, high SIRT1 and SIRT2 expression levels were associated with shorter recurrence-free survival (P=0.04 and P=0.007, respectively). Moreover, the combination of high SIRT1 and SIRT2 expression was an independent prognostic factor for shorter recurrence-free survival (P=0.002) and overall survival (P=0.022). In vitro studies showed that SIRT1 and/or SIRT2 downregulation significantly decreased proliferation of NSCLC.

Conclusions

Our results support the hypothesis that SIRT1 and SIRT2 have a protumorigenic role in lung cancer, promoting cell proliferation. Moreover, the expression of these proteins is associated with poor prognosis in NSCLC patients and may help to identify those NSCLC patients with high risk of recurrence that could benefit from adjuvant therapy after resection.     

Ano1/TMEM16A Overexpression Is Associated with Good Prognosis in PR-Positive or HER2-Negative Breast Cancer Patients following Tamoxifen Treatment

The calcium-activated chloride channel Ano1 (TMEM16A) is overexpressed in many tumors. Although Ano1 overexpression is found in breast cancer due to 11q13 amplification, it remains unclear whether signaling pathways are involved in Ano1 overexpression during breast cancer tumorigenesis in vivo. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) have been known to contribute to breast cancer progression. It is unclear whether Ano1 is associated with clinical outcomes in breast cancer patients with different ER, PR and HER2 status. In the present study, we investigated the Ano1 expression in 431 patients with invasive ductal breast carcinoma and 46 patients with fibroadenoma, using immunohistochemistry, and analyzed the association between Ano1 expression and clinical characteristics and outcomes of breast cancer patients with different ER, PR, and HER2 status. Ano1 was overexpressed in breast cancer compared with fibroadenoma. Ano1 was significantly more associated with breast cancer with the lower clinical stage (stage I or II), or triple-negative status. Mostly importantly, Ano1 overexpression was associated with good prognosis in patients with the PR-positive or HER2-negative status, and in patients following tamoxifen treatment. Multivariate Cox regression analysis showed that Ano1 overexpression was a prognostic factor for longer overall survival in PR-positive or HER2-negative patients, and a predictive factor for longer overall survival in patients following tamoxifen treatment. Our findings suggest that Ano1 may be a potential marker for good prognosis in PR-positive or HER2-negative patients following tamoxifen treatment. The PR and HER2 status defines a subtype of breast cancer in which Ano1 overexpression is associated with good prognosis following tamoxifen treatment.