Sal-like Protein 4 Expression Research Articles

Long noncoding HOXA11-AS knockdown suppresses the progression of non-small cell lung cancer by regulating miR-3619-5p/SALL4 axis.

Accumulating evidence suggested that many long noncoding RNAs (lncRNAs) were widely involved in the development and progression of non-small cell lung cancer (NSCLC). However, the roles of lncRNA homeobox A11 antisense (HOXA11-AS) and its underlying mechanism in NSCLC remains largely unknown. The expression levels of HOXA11-AS, miR-3619-5p and sal-like protein 4 (SALL4) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot analysis was used to measure the protein levels of hexokinase II (HK2) and SALL4. Cell proliferation, apoptosis, migration and invasion were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry and transwell assay, respectively. The glucose consumption and lactate production were measured using glucose assay kit and lactate assay kit, respectively. The potential binding sites between miR-3619-5p and HOXA11-AS or SALL4 were predicted by online software and verified by luciferase report assay. A xenograft tumor model was established to confirm the function of HOXA11-AS in NSCLC in vivo. HOXA11-AS and SALL4 were upregulated while miR-3619-5p was downregulated in NSCLC tissues and cells. HOXA11-AS knockdown suppressed cell proliferation, migration, invasion, and glycolysis but promoted apoptosis in NSCLC cells. Moreover, miR-3619-5p could directly bind to HOXA11-AS and its inhibition attenuated the inhibitory effect of HOXA11-AS knockdown on progression of NSCLC cells. Furthermore, SALL4 was a direct target of miR-3619-5p and its overexpression reversed the anti-tumor role of miR-3619-5p in NSCLC cells. Besides, HOXA11-AS modulated SALL4 expression via sponging miR-3619-5p. Additionally, silencing HOXA11-AS inhibited tumor growth though upregulating miR-3619-5p and downregulating SALL4. Collectively, HOXA11-AS knockdown inhibited the progression of NSCLC by regulating miR-3619-5p/SALL4 axis, which might offer a novel avenue for interpreting the mechanism of NSCLC development.

SALL4 promotes tumor progression in breast cancer by targeting EMT.

Sal-like protein 4 (SALL4) is overexpressed in breast cancer and might contribute to breast cancer progression, but the molecular mechanism remains unknown. Here, we found that within a group of 371 ethnic Chinese breast cancer patients, SALL4 was associated with lower grade (P = .002) and progesterone receptor positivity (P = .004) for overall cases; lower Ki67 (P = .045) and high vimentin (P = .007) for luminal cases. Patients with high SALL4 expression in lymph node metastasis showed a significantly worse survival than those with low expression. Knockout of SALL4 in a triple-negative breast cancer cell line MDA-MB-231-Red-FLuc-GFP led to suppressed ability in proliferation, clonogenic formation, migration, and mammosphere formation in vitro, tumorigenicity and lung colonization in vivo. On the other hand, overexpression of SALL4 enhanced migration and mammosphere formation in vitro and tumorigenicity in vivo. Mechanistically, there was a positive correlation between SALL4 expression and mesenchymal markers including Zinc finger E-box binding homeobox 1 (ZEB1), vimentin, Slug, and Snail in vivo. Chromatin immunoprecipitation experiment indicated that SALL4 can bind to the promoter region of vimentin (-778 to -550 bp). Taken together, we hypothesize that SALL4 promotes tumor progression in breast cancer by inducing the mesenchymal markers like vimentin through directly binding to its promoter. Increased SALL4 level in metastatic lymph node relative to the primary site is an important poor survival marker in breast cancer.

SALL4 Expression in Urothelial Carcinoma of Urinary Bladder; a Tissue Microarray Analysis

Sal-like protein 4 (SALL4) is a cellular pluripotent embryonic nuclear factor that has been a useful immunohistochemistry marker for germ-cell tumors. Our understanding of SALL4 expression in other human body malignancies remains limited. The diagnostic value of SALL4 expression as an independent diagnostic marker for patients with bladder urothelial carcinoma remains unclear. The aim of this study is to investigate the relation of SALL4 immunostaining in urinary bladder urothelial carcinoma and normal bladder urothelial tissue with clinicopathological diagnostic parameters. Material and methods: Three hundred and seventy cases of bladder urothelial carcinomas and 22 non-neoplastic bladder urothelial tissues were obtained from the Department of Pathology at King Abdulaziz University Jeddah, Saudi Arabia. Tissue microarrays were constructed. Tissue sections were stained using anti-human SALL4 monoclonal antibody. The immunostaining results were recorded and analyzed. Results: SALL4 exhibited weak nuclear expression in only 6 out of 370 cases of bladder urothelial carcinomas (1.6%). All the SALL4-positive cases were high-grade tumors. Normal urothelial tissues were all completely negative. SALL4 immunostaining revealed no association with gender, age, tumor invasiveness, stage, lymphovascular invasion, regional lymph node metastasis, or distant metastasis. Conclusion: SALL4 is rarely expressed in bladder urothelial carcinoma and is typically limited to high-grade tumors. However, this immunoexpression must be kept in mind when applying SALL4 antibody for differentiating urothelial carcinomas from germ-cell tumors and when assessing metastatic poorly differentiated tumors of unknown origin.

SMARCA4/BRG1-Deficient Non-Small Cell Lung Carcinomas: A Case Series and Review of the Literature.

Somatic mutations in SMARCA4 (SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4) gene and/or BRG1 (Brahma-related gene 1) loss identifies a subset of non-small cell lung carcinomas (NSCLCs) lacking alterations in EGFR (epidermal growth factor receptor), ALK (anaplastic lymphoma kinase), and ROS1 (ROS proto-oncogene 1) genes. Preliminary observations suggest responsiveness to immunotherapy and targeted therapies. To study BRG1 loss in NSCLCs and elucidate the clinicopathologic profile of such SMARCA4-deficient NSCLCs. Non-small cell lung carcinomas diagnosed during 6 years were subject to immunohistochemistry for BRG1 and BRM (Brahma). Tumors with BRG1 loss were stained with antibodies against thyroid transcription factor 1 (TTF-1), p40, cytokeratins, hepatocyte paraffin 1 (Hep Par 1), Sal-like protein 4 (SALL4), CD34, SRY-box 2 (SOX2), chromogranin, synaptophysin, p53, integrase interactor 1, ALK, and ROS1. EGFR mutation testing was performed by polymerase chain reaction-based method. Among 100 NSCLCs tested, 4 cases (4%) showed BRG1 loss. The histology ranged from solid adenocarcinomas (n = 1) to large cell/poorly differentiated carcinomas (n = 3) with clear cell cytology in 2 cases. All showed loss/reduction of BRM with variable cytokeratin and SALL4 expression, and were negative for TTF-1, p40, Hep Par 1, ALK, ROS1, and EGFR mutations. CD34 and SOX2 were negative in all 4 cases. Isolated BRM loss was common (21%), distributed across all NSCLC subtypes including squamous cell carcinomas and a hepatoid adenocarcinoma. BRG1 loss occurs in a subset of TTF-1/p40-negative poorly differentiated NSCLCs. Identification and follow-up will clarify the prognosis, diagnostic criteria, and potential for therapeutic personalization.

Overexpression of Sal-like protein 4 in head and neck cancer: epigenetic effects and clinical correlations.

Sal-like protein 4 (SALL4), an embryonic stem cell factor, has been reported to play an essential role in embryogenesis and oncogenesis. As yet, however, the expression and role of this transcription factor in head and neck squamous cell carcinoma (HNSCC) has not been established. We assessed SALL4 mRNA expression in a well-characterised dataset of 230 HNSCC samples (test cohort 110 cases and validation cohort 120 cases). We also transfected HNSCC cells (FaDu and UM-SCC-6) with SALL4 siRNA and assessed its effects on proliferation and expression of specific epigenetic factors in order to uncover the role of SALL4 in HNSCC. Overexpression of SALL4 was detected in tumour samples of both cohorts. HNSCC cells treated with SALL4 siRNA showed a reduction in growth and a decrease in DNA methyltransferase 3 alpha (DNMT3A) expression. In the patient cohorts, SALL4 overexpression was found to significantly correlate with disease recurrence (p < 0.001) and SALL4 methylation status (p = 0.002). We also found that DNMT3A was significantly upregulated upon SALL4 upregulation (p < 0.001). High expression levels of SALL4 correlated with decreases in disease-free survival (DFS) rates (log-rank test, p < 0.001). Multivariate analysis revealed that SALL4 expression served as an independent prognostic factor for DFS (hazard ratio: 2.566, 95% confidence interval: 1.598-4.121; p < 0.001). Our findings indicate that SALL4 upregulation correlates with HNSCC tumour aggressiveness and an adverse patient outcome. Our findings also indicate that DNMT3A may synergistically contribute to the regulatory effects of SALL4. Our findings provide insight into SALL4-mediated HNSCC development via epigenetic modulation.

Effect of sal-like protein 4 gene on proliferation of glioma cells

Objective To investigate the expression of sal-like protein 4 (SALL4) gene in glioma and the effect of SALL4 gene on proliferation of glioma cells. Methods By bioinformatics, the data from The Cancer Genome Atlas (TCGA) were analyzed to explore the expression of SALL4 gene and its relation to prognosis. qPCR was used to detect the expression of SALL4 in 56 cases of grade Ⅲ and grade Ⅳ glioma samples according to the World Health Organization (WHO) classification system and 6 cases of non-tumor brain tissue. Cell counting kit-8 (CCK-8) test and cell cycle test were performed to detect the proliferation of glioma cells after knocking down the SALL4 gene. The protein expression of SALL4 and phosphatase and tensin homologue deleted on chromosome ten (PTEN) was detected by Western blotting after SALL4 gene was silenced. Results Data from TCGA showed that SALL4 gene was highly expressed in tumors, and about 50% of patients with glioblastoma with low expression of SALL4 had higher survival rate; The expression of SALL4 in 56 high grade glioma samples was higher than that in 6 non-tumor brain tissues (2.89±2.53 vs. 0.70±0.30), and its high expression had a relation to early survival rate. After the SALL4 gene was silenced, the proliferation of glioma cells was inhibited, and the expression of PTEN was increased. Conclusion SALL4 gene is involved in the regulation of the growth of glioma cells. And inhibiting the expression of SALL4 gene can inhibit the proliferation of glioma cells. Key words: Glioma; Sal-like protein 4 gene; Proliferation

Upregulation of SALL4 by EGFR activation regulates the stemness of CD44-positive lung cancer

The transcriptional factor SALL4, an important stem cell regulator, is expressed in hematopoietic stem cells and various malignancies, but its role in EGFR-mutated NSCLCs has not been studied yet. Here, we report that the expression of Sal-like protein 4 (SALL4), was significantly higher in EGFR mutated lung tumors than in non-tumor tissue. SALL4-high lung cancer patients had poorer prognosis after surgery than SALL4-low patients. The expression of SALL4 could be induced by the activation of EGFR through the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. The knockdown of SALL4 expression could suppress spheroid formation and the expression of lung cancer stem cell marker CD44. More interestingly, the knockdown of SALL4 expression could suppress the migration, invasion, and metastasis of the lung cancer cells and significantly increase the sensitivity of EGFR mutated cells to Erlotinib. These results suggest that SALL4 may be a novel potential therapeutic target for the diagnosis and treatment of lung cancer.

Methylation-induced downregulation and tumor-suppressive role of microRNA-98 in glioma through targeting Sal-like protein 4.

MicroRNAs (miRs) have been found to play key roles in various human cancers, but the detailed regulatory mechanism of miR-98 in glioma remains largely unknown. The findings of the present study demonstrated that miR-98 was frequently downregulated in glioma tissues and cell lines (U87, U251, U373 and SHG44), and the decreased miR-98 levels were associated with DNA methylation. Treatment with 5-Aza-20-deoxycytidine, a DNA methyltransferase inhibitor, significantly increased the expression of miR-98 in glioma cells. Moreover, both miR-98 downregulation and methylation were significantly associated with a more aggressive tumor phenotype in glioma, as well as shorter survival time of glioma patients. Restoration of miR-98 expression caused a marked decrease in the migration and invasion of U87 cells, but did not affect cell proliferation. Sal-like protein 4 (SALL4) was further identified as a novel target gene of miR-98, and its protein expression was negatively regulated by miR-98 in U87 cells. Restoration of SALL4 expression reversed the suppressive effects of miR-98 on the migration and invasion of U87 cells. Furthermore, SALL4 was significantly upregulated in glioma tissues and cell lines, and an inverse correlation between miR-98 and SALL4 expression in glioma tissues was identified. In addition, the increased expression of SALL4 was significantly associated with glioma progression. Taken together, these data demonstrated that downregulation of miR-98, induced by methylation, promotes glioma cell migration and invasion via targeting SALL4. Therefore, miR-98 may become a potential therapeutic candidate for glioma.

MicroRNA-219 exerts a tumor suppressive role in glioma via targeting Sal-like protein 4.

MicroRNAs (miRs) serve important roles in the development and progression of various human cancer types, including glioma. Recently, miR-219 has been suggested to function as a tumor suppressor in glioma; however, the underlying mechanism remains largely unknown. The aim of this study was to investigate the regulatory mechanism of miR-219 in the malignant phenotypes of glioma cells. Quantitative polymerase chain reaction (qPCR) and western blotting were conducted to examine the mRNA and protein expression. An MTT assay, wound healing assay and Transwell assay were used to study cell proliferation, migration and invasion. The qPCR data indicated that the expression of miR-219 was significantly decreased in glioma tissues compared with normal brain tissues. In addition, a low expression of miR-219 was identified to be associated with an advanced pathological grade. In vitro experiments demonstrated that miR-219 was also downregulated in several common glioma cell lines, including A172, U87, U251 and U373, when compared with that in normal astrocytes. Ectopic expression of miR-219 caused a significant decrease in U87 cell proliferation, migration and invasion. Luciferase reporter assay data indicated that Sal-like protein 4 (SALL4) was a direct target gene of miR-219, while the protein expression of SALL4 was negatively regulated by miR-219 in U87 cells. Furthermore, SALL4 was significantly upregulated in glioma tissues and cell lines, and upregulation of SALL4 was associated with a higher pathological grade. Furthermore, overexpression of SALL4 significantly attenuated the suppressive effects of miR-219 on U87 cell proliferation, migration and invasion, suggesting that miR-219 serves a suppressive role in glioma growth and metastasis via targeting SALL4. Therefore, the present study highlighted the clinical significance of the miR-219/SALL4 axis in glioma.

Fetal gut–like differentiation in gallbladder cancer

Adenocarcinomas showing fetal gut-like (enteroblastic) differentiation can arise in a variety of organs and are frequently accompanied by an elevated serum α-fetoprotein (AFP) level. However, no study has investigated fetal gut-like differentiation in gallbladder cancer in detail. Herein, we performed morphological and immunohistochemical analyses of fetal gut-like differentiation in 49 consecutive gallbladder cancer cases. The expression of Sal-like protein 4 (SALL4), an embryonic stem cell marker reported to represent fetal gut-like differentiation, as well as other oncofetal proteins, including glypican-3 (GPC3) and AFP, was assessed. We found 1 case of fetal gut-like adenocarcinoma that coexisted with conventional-type adenocarcinoma. The fetal gut-like adenocarcinoma component revealed diffuse immunoreactivity for SALL4 and partial positivity for AFP, whereas the conventional-type adenocarcinoma component was negative. We also found 2 poorly differentiated adenocarcinomas with hepatoid morphology and 1 clear cell carcinoma, none of which showed SALL4 positivity. In other conventional-type adenocarcinomas, focal immunoreactivity for SALL4 and GPC3 was occasionally observed. The overall positivity rates for SALL4 and GPC3 were 12.2% (6/49) and 16.3% (8/49), respectively. SALL4 and GPC3 expression was not associated with clinicopathological factors, including T category, lymphovascular invasion, and lymph node metastases. In conclusion, fetal gut-like adenocarcinoma was found in 2% of our gallbladder cancer series. We conclude that fetal gut-like adenocarcinoma is a distinct histological subtype of gallbladder cancer, characterized by SALL4 expression.

MicroRNA-181b Inhibits Cellular Proliferation and Invasion of Glioma Cells via Targeting Sal-Like Protein 4.

MicroRNAs (miRs), a class of noncoding RNAs that are 18–25 nucleotides in length, are able to suppress gene expression by targeting complementary regions of mRNAs and inhibiting protein translation. Recently, miR-181b was found to play a suppressive role in glioma, but the regulatory mechanism of miR-181b in the malignant phenotypes of glioma cells remains largely unclear. In this study, we found that miR-181b was significantly downregulated in glioma tissues when compared with normal brain tissues, and decreased miR-181b levels were significantly associated with high-grade pathology and a poor prognosis for patients with glioma. Moreover, miR-181b was downregulated in glioma cell lines (U87, SHG44, U373, and U251) compared to normal astrocytes. Overexpression of miR-181b significantly decreased the proliferation, migration, and invasion of glioma U251 cells. Sal-like protein 4 (SALL4) was identified as a novel target gene of miR-181b in U251 cells. The expression of SALL4 was significantly upregulated in glioma tissues and cell lines, and an inverse correlation was observed between the miR-181b and SALL4 expression levels in glioma. Further investigation showed that the protein expression of SALL4 was negatively regulated by miR-181b in U251 cells. Knockdown of SALL4 significantly inhibited the proliferation, migration, and invasion of U251 cells, while overexpression of SALL4 effectively reversed the suppressive effects of miR-181b on these malignant phenotypes of U251 cells. In conclusion, our study demonstrates that miR-181b has a suppressive effect on the malignant phenotypes of glioma cells, at least partly, by directly targeting SALL4. Therefore, the miR-181b/SALL4 axis may become a potential therapeutic target for glioma.

Higher expression of SALL4 predicts poor cancer prognosis: A meta-analysis.

Sal-like protein 4 (SALL4) is recognized as a potential biomarker for assessing cancer prognosis. Many experiments have been done to explore the aberrant expression of SALL4 in cancer patients. To explore the association between SALL4 expression and cancer prognosis. A systematically comprehensive search was performed through PubMed, Web of Science, and CNKI. The prognostic value of SALL4 expression in cancer patients was evaluated by pooled hazard ratios (HRs) and 95% confidence intervals (CIs). The overexpression of SALL4 was identified to be significantly associated with a poor prognosis in cancer patients (pooled HR: 2.02, 95% CI: 1.67-2.46). This association was also detected in digestive system neoplasms subgroup (pooled HR: 1.91, 95% CI: 1.52-2.39) and reproductive system neoplasms subgroup (pooled HR: 1.95, 95% CI: 1.17-3.26). In the geography subgroup analysis, a statistical association was confirmed in the Chinese subgroup (pooled HR: 1.982, 95% CI: 1.526-2.576). In the respect of disease progression, there was a certain degree of relationship between higher expression of SALL4 and recurrence-free survival (RFS) (pooled HR: 1.617, 95% CI: 1.190-2.196). SALL4 is a promising prognostic biomarker for cancer, and is appropriate for the assessment of cancer prognosis in the Chinese people.

Stage-specific expression of Sal-like protein 4 in boar testicular germ cells

Spermatogenesis, the complex process of sperm cell development including mitotic cell division and meiosis, relies on spermatogonial stem cells (SSCs). While markers for developing germ cells have been well investigated in mice, developmental stage-specific markers of germ cells in domestic animals have not been identified. Sal-like protein 4 (SALL4) is known as a putative marker for undifferentiated spermatogonia in rodents; however, its expression in domestic animals has not been investigated. The objective of this study was to characterize the expression of SALL4 in the developmental stages of boar testes and SSCs. Interestingly, all SALL4-expressing cells responded positively to PGP9.5, which is known as a spermatogonia marker in boar testes, while some PGP9.5-positive cells did not express SALL4 in pre-pubertal boar testes. At this stage, the expression of SALL4 was observed in GFRα1-positive cells, and its expression was maintained in cultured pSSCs in vitro, suggesting that SALL4 is a marker of early-stage boar spermatogonia that express GFRα1 in pre-pubertal testes. Additionally, SALL4 expression was observed in c-Kit-positive but not in PGP9.5- or SCP3-positive cells in post-pubertal testes. In conclusion, SALL4 is expressed in early undifferentiated spermatogonia in pre-pubertal boar testes and in primary spermatocytes in post-pubertal boar testes. Therefore, SALL4 can be used as a stage-specific marker of developing germ cells in boar testes.

DNA demethylation induces SALL4 gene re-expression in subgroups of hepatocellular carcinoma associated with Hepatitis B or C virus infection.

Sal-like protein 4 (SALL4), an embryonic stem cell transcriptional regulator, is re-expressed by an unknown mechanism in poor prognosis hepatocellular carcinoma (HCC), often associated with chronic hepatitis B virus (HBV) infection. Herein, we investigated the mechanism of SALL4 re-expression in HBV-related HCCs. We performed bisulfite sequencing PCR of genomic DNA isolated from HBV-related HCCs and HBV replicating cells, and examined DNA methylation of a CpG island located downstream from SALL4 transcriptional start site (TSS). HBV-related HCCs expressing increased SALL4 exhibited demethylation of specific CpG sites downstream of SALL4 TSS. Similarly, SALL4 re-expression and demethylation of these CpGs was observed in HBV replicating cells. SALL4 is also re-expressed in poor prognosis HCCs of other etiologies. Indeed, increased SALL4 expression in hepatitis C virus-related HCCs correlated with demethylation of these CpG sites. To understand how CpG demethylation downstream of SALL4 TSS regulates SALL4 transcription, we quantified by chromatin immunoprecipitation (ChIP) assays RNA polymerase II occupancy of SALL4 gene, as a function of HBV replication. In absence of HBV replication, RNA polymerase II associated with SALL4 exon1. By contrast, in HBV replicating cells RNA polymerase II occupancy of all SALL4 exons increased, suggesting CpG demethylation downstream from SALL4 TSS influences SALL4 transcriptional elongation. Intriguingly, demethylated CpGs downstream from SALL4 TSS are within binding sites of octamer-binding transcription factor 4 (OCT4) and signal transducer and activator of transcription3 (STAT3). ChIP assays confirmed occupancy of these sites by OCT4 and STAT3 in HBV replicating cells, and sequential ChIP assays demonstrated co-occupancy with chromatin remodeling BRG1/Brahma-associated factors. BRG1 knockdown reduced SALL4 expression, whereas BRG1 overexpression increased SALL4 transcription in HBV replicating cells. We conclude demethylation of CpGs located within OCT4 and STAT3 cis-acting elements, downstream of SALL4 TSS, enables OCT4 and STAT3 binding, recruitment of BRG1, and enhanced RNA polymerase II elongation and SALL4 transcription.

MicroRNA-33b suppresses the proliferation and metastasis of hepatocellular carcinoma cells through the inhibition of Sal-like protein 4 expression.

MicroRNAs (miRNAs or miRs) have been found to participate in the development and malignant progression of human cancers by negatively mediating the expression of their target genes. Recently, miR‑33b has been reported to be involved in multiple types of human cancer, including hepatocellular carcinoma(HCC). However, the underlying regulatory mechanisms of miR‑33b in HCC cell growth and metastasis remain largely unclear. In the present study, RT-qPCR revealed that miR‑33b was significantly downregulated in HCC tissues compared to their matched adjacent normal tissues. Moreover, the miR‑33b level was significantly lower in advanced-stage HCC (stagesT3-T4) compared to early-stage HCC (stagesT1-T2). Furthermore, it was also downregulated in the HCC cell lines, LH86, HepG2, LMH and PLHC-1, when compared with the THLE-3 normal human liver cells. We further demonstrated that the overexpression of miR‑33b led to a significant decrease in the proliferation, migration and invasion of HepG2 and LH86 cells. Luciferase reporter assay identified Sal-like protein4(SALL4) as a target gene of miR‑33b, and its protein expression was negatively regulated by miR‑33b in HepG2 and LH86 cells. Moreover, the restoration of SALL4 expression markedly reversed the inhibitory effect of miR‑33b overexpression on the proliferation, migration and invasion of HepG2 and LH86 cells, indicating that SALL4 is involved in miR‑33b-mediated malignant phenotypes of HCC cells. Furthermore, we found that SALL4 was significantly upregulated in HCC tissues compared to their matched adjacent normal tissues, and its increased expression was significantly associated with the advanced malignancy of HCC. Moreover, SALL4 was also upregulated in HCC cell lines compared to the THLE-3 normal human liver cells. Finally, we found that the SALL4 expression inversely correlated with the miR‑33b level in HCC tissues. On the whole, the findings of our study demonstrate that miR‑33b suppresses the proliferation and metastasis of HCC cells through the inhibition of SALL4 expression. Therefore, miR‑33b/SALL4 may become a potential therapeutic target for the treatment of HCC.

Metastatic Treated Malignant Germ Cell Tumors: Is SALL4 a Better Marker Than Placental Alkaline Phosphatase?

Studies have shown that in the metastatic setting and after treatment, expression of immunohistochemical markers may be diminished or lost. Transcription factor SALL4 (sal-like protein 4) has been recognized as a sensitive marker for both primary and metastatic malignant germ cell tumors (MGCTs), but has not been tested in the posttreatment setting. We sought to determine the level of SALL4 expression in treatment-resistant metastatic MGCT in comparison with pan-GCT marker placental alkaline phosphatase (PLAP). Thirty-six previously treated MGCTs, 16 untreated primary testicular MGCTs, and 4 cytology specimens were immunostained for SALL4 and PLAP, and staining characteristics were evaluated. In the treated MGCT group, there was diffuse SALL4 nuclear immunoreactivity in the majority of cases (27/36, 75%), labeling seminoma, yolk-sac tumor, embryonal carcinoma, and primitive neuroectodermal components. No treated metastatic MGCT lacked SALL4 immunoreactivity. In contrast, PLAP was diffusely expressed in only 14/36 (39%) cases of treated MGCTs, showed scattered focal weak to moderate positivity in 13/36 (36%), and was virtually absent in 9/36 (25%) cases. Both markers had scattered expression limited to the epithelial components of teratomatous regions. SALL4 also outperformed PLAP on a small sample of cytology blocks. Although SALL4 is not entirely specific, it is a highly sensitive marker with strong diffuse nuclear reactivity in the majority of MGCTs in the posttreatment setting, at significantly higher levels than PLAP (P<0.001). Persistent expression of SALL4 in metastatic MGCTs resistant to chemoradiation also raises the possibility for targeted systemic therapy as the anti-SALL4 peptide continues to be developed.

Importance of SALL4 in the development and prognosis of hepatocellular carcinoma.

To detect the expression of sal-like protein 4 (SALL4) and to explore its relationship with clinicopathological characteristics and prognosis of hepatocellular carcinoma (HCC). One hundred and twenty-six samples of HCC tissue, 44 of adjacent noncancerous cirrhotic tissue and 10 of liver hemangioma tissue, were obtained from patients who underwent hepatectomy for HCC at the Fourth Hospital of Hebei Medical University. None of the patients had received any form of treatment before the operation. After resection, all the tissues were fixed in 10% neutral formaldehyde and embedded in paraffin. Expression of SALL4 was detected by immunohistochemistry. Patients were followed up for postoperative survival until February 2014. The relationships between SALL4 expression level and clinicopathological data and prognosis of HCC were analyzed. SALL4 expression was negative in the 10 samples of tissue from liver hemangioma, was weakly positive in the two samples from adjacent noncancerous cirrhotic tissue, and positive in 58 samples of HCC tissues. The differences were statistically significant (P < 0.05). Expression of SALL4 was higher in patients with higher α-fetoprotein (AFP) levels, portal vein tumor thrombus, and later clinical stage based on the Barcelona Clinic Liver Cancer classification (P < 0.05). Among patients with negative expression, weakly positive expression, positive expression, and strongly positive expression of SALL4, the median survival time was 39, 25, 23, and 9 mo, respectively (P < 0.001). When both AFP and SALL4 were detected, patients who were negative for both AFP and SALL4, SALL4-positive only, AFP-positive only, and positive for both AFP and SALL4, had a median survival time of 41, 38, 31, and 12 mo, respectively (P < 0.001). Expression of SALL4 is relevant to the prognosis of HCC patients. Patients with higher expression levels of SALL4 and AFP have worse prognosis.

Positive immunostaining of Sal-like protein 4 is associated with poor patient survival outcome in the large and undifferentiated Korean hepatocellular carcinoma

PurposePrevious studies have shown the role of Sal-like protein 4 (SALL4) as a biomarker in hepatocellular carcinoma (HCC), and some studies have shown the relationship between SALL4 and prognosis. Given the debates in study groups differences in terms of etiologic causes between Western and Asian HCC and detection methods, we attempted to verify the features of SALL4 immunoreactivity and its clinical correlation in Korean HCC patients.MethodsImmunohistochemical staining of SALL4 of tissue microarrays (TMAs) consisting of 213 surgically resected HCC patients' tissue were scored in a semiquantitative scoring system with immunoreactive score and the results analyzed with clinical outcome, in addition to general demographics and clinical characteristics.ResultsSALL4 immunoreactivity was expressed in 50 cases. Relevance between SALL4 and α-FP correlated significantly (P = 0.002). Also, the SALL4-positive patients had considerably higher tumor grade (P < 0.001). The survival analysis showed negative correlation with SALL4 immunoreactivity in all HCC patient groups, but SALL4 immunoreactivity in T3 and T4 HCC correlated with poor prognosis.ConclusionHere, we found that positive immunostaining of SALL4 is correlated with poor patient survival outcome in large and undifferentiated Korean HCC. SALL4 expression showed close relationship with clinical outcomes of HCCs in Korean patients.

Expression and clinical significance of SALL4 and LGR5 in patients with lung cancer.

Lung cancer is the most frequent cancer worldwide, in terms of incidence and mortality. Due to challenges in the diagnosis of the disease, the 5-year overall survival rate is only ~16%. Previous studies have suggested that malignant transformations originate from adult stem cells, and malignant lesions may therefore express stem-cell-associated markers. The purpose of the present study is to investigate the expression and clinical significance of the stem cell-associated markers Sal-like protein 4 (SALL4) and leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) in lung cancer, and to provide novel diagnostic markers and targets for the treatment of lung cancer. The expression of the stem cell-associated markers SALL4 and LGR5 was analyzed by immunohistochemistry performed on 135 human lung cancer tissue specimens and 10 non-cancer lung tissue specimens. The clinical significance of the expression of these markers and correlation between their expression and clinical parameters was also assessed. SALL4 expression was highly upregulated in lung cancer tissues, but was not present in non-cancerous lung tissues, and the sensitivity and specificity of SALL4 reached 88% and 100%, respectively. By contrast, LGR5 demonstrated 97% sensitivity, but the specificity was poor. Therefore, SALL4 may be an extremely useful diagnostic marker for lung cancer, but LGR5 is not as useful.

SALL4 Expression in Hepatocellular Carcinomas Is Associated with EpCAM-Positivity and a Poor Prognosis.

Background:There is increasing interest in hepatocellular carcinomas (HCC) expressing “stemness”-related markers, as they have been associated with aggressive behavior and poor prognosis. In this study, we investigated the usefulness of Sal-like protein 4 (SALL4), a recently proposed candidate marker of “stemness.”Methods:Immunohistochemical stains were performed for SALL4, K19, and epithelial cellular adhesion molecule (EpCAM) on tissue microarrays constructed from 190 surgically resected HCCs, and the results were correlated with the clinicopathological features and patient survival data.Results:Nuclear SALL4 expression was observed in 39/190 HCCs (20.5%), while K19 and EpCAM were expressed in 30 (15.9%) and 92 (48.7%) HCCs, respectively. The nuclear expression was generally weak, punctate or clumped. SALL4 expression was significantly associated with a poor overall survival compared to SALL4-negative HCCs (p = .014) compared to SALL4-negative HCCs. On multivariate analysis adjusted for tumor size, multiplicity, vascular invasion, and pathological tumor stage, SALL4 remained as a significant independent predictor of decreased overall survival (p= .004). SALL4 expression was positively correlated with EpCAM expression (p = .013) but not with K19 expression. HCCs that expressed both SALL4 and EpCAM were associated with significantly decreased overall survival, compared to those cases which were negative for both of these markers (p = .031).Conclusions:Although SALL4 expression was not significantly correlated with other clinicopathological parameters suggestive of tumor aggressiveness, SALL4 expression was an independent predictor of poor overall survival in human HCCs, and was also positively correlated with EpCAM expression.