Expression of synuclein gamma indicates poor prognosis of triple-negative breast cancer

Cancer in pathologically confirmed multiple system atrophy

PURPOSE

The aim of this study was to assess whether cancer occurs with increased frequency in multiple system atrophy (MSA). The pathological hallmark of MSA is glial cytoplasmic inclusions containing aggregated α-synuclein, and the related protein γ-synuclein correlates with invasive cancer. We investigated whether these two disorders are associated clinically.

METHODS

Medical records of 320 patients with pathologically confirmed MSA seen between 1998 and 2022 were reviewed. After excluding those with insufficient medical histories, the remaining 269 and an equal number of controls matched for age and sex were queried for personal and family histories of cancer recorded on standardized questionnaires and in clinical histories. Additionally, age-adjusted rates of breast cancer were compared with US population incidence data.

RESULTS

Of 269 cases in each group, 37 with MSA versus 45 of controls had a personal history of cancer. Reported cases of cancer in parents were 97 versus 104 and in siblings 31 versus 44 for MSA and controls, respectively. Of 134 female cases in each group, 14 MSA versus 10 controls had a personal history of breast cancer. The age-adjusted rate of breast cancer in MSA was 0.83%, as compared with 0.67% in controls and 2.0% in the US population. All comparisons were nonsignificant.

CONCLUSION

The evidence from this retrospective cohort found no significant clinical association of MSA with breast cancer or other cancers. These results do not exclude the possibility that knowledge about synuclein pathology at the molecular level in cancer may lead to future discoveries and potential therapeutic targets for MSA.

Expression of Jagged1/Notch3 Signaling Pathway and their Relationship with the Tumor Angiogenesis in TNBC

BACKGROUND AND AIMS

Jagged1/Notch3 signaling pathway plays a key role in angiogenesis of breast cancer, but little is known in TNBC. This study was designed to investigate the expression of Jagged1/Notch3 mRNA and protein in TNBC, analyze their correlations with clinicopathological characteristics and prognosis. Moreover, the interrelationship among Jagged1/Notch3 and VEGF was initially evaluated.

METHODS

Jagged1/Notch3 mRNA and protein expression levels were determined by Q-RT-PCR and Western blotting. Additionally, Immunohistochemistry for Jagged1/Notch3 was detected by Ventana platform, VEGF and CD34 was performed using the EnVision/HRP technique.

RESULTS

mRNA transcriptionof Jagged1/Notch3 was in accord with protein expression. TNBC patients with positive Jagged1 expression had poorer DFS (p = 0.008) and OS (p = 0.004). Jagged1 expression was independent predictors of OS (p = 0.038). The expression of VEGF was positively correlative to MVD (p = 0.018), MVD was significantly associated with Jagged1 (p <0.0001) and Notch3 (p <0.0001). The expression of Jagged1/Notch3 has no correlation with VEGF, only in positive VEGF expression of TNBC patients Jagged1/Notch3 had influence on DFS and OS (p <0.05).

CONCLUSION

Jagged1/Notch3 was -expressed at both the mRNA and protein levels, Jagged1 served as an independent predictor of poor prognosis. We speculate that there is a cross-talk between Jagged1/Notch3 and VEGF in TNBC angiogenesis. Jagged1/Notch3 is expected to be an important signaling pathway for TNBC progression and a potential target for TNBC neovascularization therapy.

Synuclein-γ in uterine serous carcinoma impacts survival: An NRG Oncology/Gynecologic Oncology Group study

BACKGROUND

Synuclein-γ (SNCG) is highly expressed in advanced solid tumors, including uterine serous carcinoma (USC). The objective of the current study was to determine whether SNCG protein was associated with survival and clinical covariates using the largest existing collection of USCs from the Gynecologic Oncology Group (GOG-8023).

METHODS

High-density tissue microarrays (TMAs) of tumor tissues from 313 patients with USC were stained by immunohistochemistry for SNCG, p53, p16, FOLR1, pERK, pAKT, ER, PR, and HER2/neu. Associations of SNCG and other tumor markers with overall and progression-free survival were assessed using log-rank tests and Cox proportional-hazards models, which also were adjusted for age, race, and stage.

RESULTS

The overall survival at 5 years was 46% for women with high SNCG expression and 62% for those with low SNCG expression (log-rank P = .021; hazard ratio [HR], 1.31; 95% confidence interval [CI], 0.91-1.9 in adjusted Cox model). The progression-free survival rate at 5 years was worse for women who had high SNCG expression, at 40%, compared with 56% for those who had low SNCG expression (log-rank P = .0081; HR, 1.36; 95% CI, 0.96-1.92 in adjusted Cox model). High levels of both p53 and p16 were significantly associated with worse overall survival (p53: HR, 4.20 [95% CI, 1.54-11.45]; p16: HR, 1.95 [95% CI, 1.01-3.75]) and progression-free survival (p53: HR, 2.16 [95% CI, 1.09-4.27]; p16: HR, 1.53 [95% CI, 0.87-2.69]) compared with low levels.

CONCLUSIONS

This largest collection of USCs to date demonstrates that SNCG was associated with poor survival in univariate analyses. SNCG does not predict survival outcome independent of p53 and p16 in models that jointly consider multiple markers. Cancer 2017;123:1144-1155. © 2016 American Cancer Society.

Alpha-synuclein contributes to malignant progression of human meningioma via the Akt/mTOR pathway

BACKGROUND

The aim of this study is to explore the expression of alpha-synuclein (α-synuclein) in benign, atypical, and anaplastic meningiomas and determine its role in the malignant progression of meningiomas.

METHODS

Expression of α-synuclein was measured in 44 meningioma samples by real-time PCR analysis. The effects of overexpression or knockdown of α-synuclein on meningioma cell growth, invasiveness, and tumorigenicity were determined.

RESULTS

Atypical and anaplastic meningiomas displayed significantly greater levels of α-synuclein mRNA, relative to benign tumors. Depletion of α-synuclein decreased cell proliferation and colony formation and promoted apoptosis in IOMM-Lee meningioma cells, whereas overexpression of α-synuclein facilitated cell proliferation and colony formation in CH-157MN meningioma cells. Silencing of α-synuclein attenuated IOMM-Lee cell migration and invasion. In contrast, ectopic expression of α-synuclein increased the invasiveness of CH-157MN cells. In vivo studies further demonstrated that downregulation of α-synuclein significantly retarded meningioma growth in nude mice. At the molecular level, the phosphorylation levels of Akt, mTOR, p70S6K and 4EBP were significantly decreased in α-synuclein-depleted IOMM-Lee cells.

CONCLUSIONS

In conclusion, α-synuclein upregulation contributes to aggressive phenotypes of meningiomas via the Akt/mTOR pathway and thus represents a potential therapeutic target for malignant meningiomas.

Interplay Between Gemcitabine and Erlotinib Over Pancreatic Adenocarcinoma Cells

OBJECTIVES

Pancreatic ductal adenocarcinoma remains as a chemoresistant disease with the poorest prognosis. Gemcitabine has been the standard treatment during the last decade. Erlotinib, a tyrosine kinase inhibitor, in combination with gemcitabine produces a small increase in survival. However, these results remain insufficient. The aim of this study was to investigate the molecular interplay in vitro between them regarding their effects over cytotoxicity, proliferation, apoptosis, and invasion.

METHODS

Using the human pancreatic cancer cell lines Panc-1 and BxPC-3 in vitro, the effects of gemcitabine and erlotinib therapy on growth, proliferation, and invasion were tested by cytotoxicity, cell cycle, and Annexin V-Fluorescein Isothiocyanate analysis, reverse transcription polymerase chain reaction, protein expression, and Chip assays.

RESULTS

Therapy decreased cell proliferation causing G0/G1 phase cell cycle arrest with induction of apoptosis in the Panc-1 cell line. This blockade was associated with increased p27 expression. Besides, treatments enhanced the nuclear factor-κB (NF-κB) pathway and the binding of NF-κB to the promoters of genes related to the proliferation and the evasion of apoptosis.

CONCLUSIONS

Our data suggest that, although gemcitabine and erlotinib exert antiproliferative effects over pancreatic cancer cell lines, the gemcitabine-induced activation of NF-κB expression and its DNA-binding activities are important drawbacks of this treatment against pancreatic cancer.

Exploring new biomarkers in the tumour microenvironment of canine inflammatory mammary tumours

Human inflammatory breast cancer (IBC) and canine inflammatory mammary cancer (CIMC) are the most aggressive forms of mammary cancer. Current research aims to identify new therapeutic targets. Here, we investigated gene expression levels of biomarkers associated with the inflammatory microenvironment. A total of 32 formalin-fixed paraffin-embedded samples of canine mammary carcinoma (CIMC = 26; non-CIMC = 6) were used and their cDNA subjected to quantitative polymerase chain reaction (qPCR) to establish gene expression levels for mediators commonly implicated in linking carcinogenesis with inflammation. Gene expression differences between CIMC and non-CIMC types were obtained for cyclooxygenase 2 (COX-2) (P = 0.004), synuclein gamma (SNCG) (P = 0.006), tribbles 1 (P = 0.025), vascular endothelial growth factor (VEGF) (P = 0.017) and CSF1R (P = 0.045). Among these biomarkers correlations were found, particularly between SNCG and tribbles 1 (r = 0.512, P = 0.001). The efficient metastasis of CIMC is intimately linked to components in the tumour microenvironment. This study suggests that upregulation and correlation of SNCG and tribbles 1 deserves to be further explored.

γ-Synuclein Expression Is a Malignant Index in Oral Squamous Cell Carcinoma

Dysregulation of γ-synuclein (SNCG) has been reported in many cancers; however, its role in cancer development is still controversial. Here, we examined the potential involvement of DNA methylation in regulating SNCG and its role in oral squamous cell carcinoma (OSCC). We used 8 OSCC cell lines to investigate SNCG methylation and expression. SNCG methylation was examination by methylation-specific polymerase chain reaction and bisulfate sequencing. Cells showing a high degree of SNCG methylation were treated with 5-aza (methylation inhibitor), and changes in their methylation and expression profiles were analyzed. Functional effects of SNCG in OSCC were examined by its overexpression and knockdown. Additionally, methylation and expression of SNCG in OSCC tissues were investigated and correlated with clinicopathologic features. All OSCC cells showed detectable SNCG expression at the mRNA and protein levels. Methylation-specific polymerase chain reaction and bisulfate sequencing revealed high SNCG expression in SCC25 cells with the unmethylated allele, and their 15 CpG islands were unmethylated. The methylated allele was detected only in OEC-M1 cells exhibiting low SNCG expression, and their CpG islands were partially methylated. 5-aza treatment in OEC-M1 cells attenuated methylation and restored SNCG expression. SNCG overexpression increased colony forming, migration, and invasion abilities in OEC-M1 cells. Silencing SNCG in SCC25 cells suppressed these behaviors. All 25 tumor-adjacent normal tissues were negative for SNCG immunostaining. SNCG upregulation was frequently observed in dysplastic and OSCC tissues. Positive SNCG expression was found in 45% (37 of 82) OSCC tissues. Positive SNCG expression in OSCC significantly correlated with cancer staging and lymph node metastasis. However, SNCG methylation did not correlate with its expression and clinicopathologic variables in OSCC tissues. DNA methylation may participate in regulating SNCG expression in some OSCC cells. SNCG upregulation could be involved in OSCC progression.

The Breast Cancer Susceptibility Gene Product (γ-Synuclein) Alters Cell Behavior through its [corrected] Interaction with Phospholipase Cβ

The breast cancer susceptibility gene protein, also known as γ-synuclein, is highly expressed in human breast cancer in a stage-specific manner, with highest expression in late stage cancer. In model systems, γ-synuclein binds phospholipase Cβ2 which is regulated by Gαq to generate intracellular Ca(2+) signals. PLCβ2, which is also absent in normal tissue but highly expressed in breast cancer, is additionally regulated by Rac to promote migration pathways. We have found that γ-synuclein binds to the same region of PLCβ2 as Gαq. Using cells that mimic stage 4 breast cancer (MDA MB 231), we show that down-regulation of γ-synuclein reduces the protein level of PLCβ but increases the transcript level over 40 fold. γ-Synuclein down-regulation also promotes the interaction between Gαq and PLCβ resulting in a stronger Ca(2+) response to Gαq agonists. The ability of γ-synuclein to interfere with Gαq-PLCβ interactions allows more PLCβ to colocalize with Rac impacting Rac-mediated pathways that may give rise to cancerous phenotypes.

Combined expression of metastasis related markers Naa10p, SNCG and PRL-3 and its prognostic value in breast cancer patients

Combinations of multiple biomarkers representing distinct aspects of metastasis may have better prognostic value for breast cancer patients, especially those in late stages. In this study, we evaluated the protein levels of N-α-acetyltransferase 10 protein (Naa10p), synuclein-γ (SNCG), and phosphatase of regenerating liver-3 (PRL-3) in 365 patients with breast cancer by immunohistochemistry. Distinct prognostic subgroups of breast cancer were identified by combination of the three biomarkers. The Naa10p+SNCG-PRL-3- subgroup showed best prognosis with a median distant metastasis-free survival (DMFS) of 140 months, while the Naa10p-SNCG+PRL-3+ subgroup had the worst prognosis with a median DMFS of 60.5 months. Multivariate analysis indicated Naa10p, SNCG, PRL-3, and the TNM classification were all independent prognostic factors for both DMFS and overall survival (OS). The three biomarker combination of Naa10p, SNCG and PRL-3 performed better in patients with lymph node metastasis, especially those with more advanced tumors than other subgroups. In conclusion, the combined expression profile of Naa10p, SNCG and PRL-3, alone or in combination with the TNM classification system, may provide a precise estimate of prognosis of breast cancer patients.

Structural insights into tumor-specific chaperoning activity of gamma synuclein in protecting estrogen receptor alpha 36 and its role in tamoxifen resistance in breast cancer

This study investigates structural aspects underlying the chaperoning activity of an intrinsically disordered protein, gamma synuclein, in promoting estrogen mediated breast cancer.

Identification of γ-synuclein as a stage-specific marker in bladder cancer by immunohistochemistry

Background

Previous studies have shown that the expression level of γ-synuclein (SNCG) is associated with progression of many different malignant tumors. In this study, we discuss and assess the prognostic ability of SNCG in bladder cancer.

Material/Methods

Medical records (2005–2013) were retrospectively reviewed for the population of interest. SNCG expression was identified immunohistochemically from bladder cancer tissues of 113 bladder cancer patients. The survival rate was calculated by the Kaplan-Meier method. Cox proportional hazard regression model was used for analysis of predictors of bladder cancer.

Results

SNCG was overexpressed in bladder cancer tissues compared with the normal bladder tissues (p<0.0001). SNCG expression in bladder cancer tissue was strongly related to tumor stage. However, SNCG level was not a prognostic factor of survival.

Conclusions

Our results demonstrate that SNCG is highly expressed in bladder cancer tissue and its expression is stage-specific, but it is not helpful for predicting outcome in bladder cancer patients.

Synuclein-gamma predicts poor clinical outcome in esophageal cancer patients

The synuclein gamma (SNCG) protein, a member of neuronal protein family synuclein, has been considered as a promising potential biomarker as an indicator of cancer stage and survival in patients with cancer. The present study was conducted to evaluate the prognostic value of SNCG in patients with esophageal carcinoma (EC). SNCG levels were assessed immunohistochemically in cancer tissues from 73 EC patients. Median age was 57 (range, 29-78) years old. Forty-seven percent of the patients were male. Thirty-seven percent of the patients had upper or middle localized tumor whereas 59 % had epidermoid carcinoma. More than half of the patients (61 %) had undergone operation where 57 % received adjuvant treatment including chemotherapy or chemotherapy plus radiotherapy. Median overall survival was 11.3 ± 1.8 months (95% confidence interval (CI): 7.7-14.9 months). SNCG positivity was significantly associated with the histological type of EC and inoperability (for SNCG positive vs. negative group; epidermoid 80 vs. 53 %; p = 0.05 and inoperable 59 vs.32 %; p = 0.04, respectively). Lymph node metastasis, inoperability and receiving no adjuvant treatment had significantly adverse effect on survival in the univariate analysis (p = 0.01, p < 0.001, and p = 0.001, respectively). SNCG positivity had significantly adverse effect on survival in both univariate and multivariate analysis (p = 0.02 and p = 0.01, respectively). Our results are the first to suggest that SNCG is a new independent predictor for poor prognosis in EC patients in the literature.

The latest progress in research on triple negative breast cancer (TNBC): risk factors, possible therapeutic targets and prognostic markers

Triple negative breast cancer (TNBC) is one type of breast cancer (BC), which is defined as negative for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (Her2). Its origins and development seem to be elusive. And for now, drugs like tamoxifen or trastuzumab which specifically apply to ER, PR or Her2 positive BC seem unforeseeable in TNBC clinical treatment. Due to its extreme malignancy, high recurrence rate and poor prognosis, a lot of work on the research of TNBC is needed. This review aims to summarize the latest findings in TNBC in risk factors, possible therapeutic targets and possible prognostic makers.