Overexpression of SPARC correlates with poor prognosis in patients with cervical carcinoma and regulates cancer cell epithelial-mesenchymal transition

Nab-paclitaxel plus platinum versus paclitaxel plus platinum as first-line therapy in patients with metastatic or recurrent cervical cancer

PURPOSE

This study aimed to assess the efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) plus platinum versus paclitaxel plus platinum as first-line therapy in patients with metastatic or recurrent cervical cancer.

METHODS

Between October 2020 and March 2022, consecutive patients with diagnosed with metastatic or recurrent cervical cancer were retrospectively recruited in our hospital. Fifty-four patients were treated with nab-paclitaxel plus cisplatin or carboplatin. Twenty-four patients were treated with paclitaxel plus cisplatin or carboplatin. A propensity score matching (PSM) analysis was done using a multivariable logistic regression model. The two groups were compared for objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) in the raw and matched dataset.

RESULTS

The nab-paclitaxel group showed a higher ORR than the paclitaxel group both in the raw dataset (72.2% vs. 45.8%; P = 0.025) and matched dataset (81.1% vs. 47.6%; P = 0.008). The median PFS was significantly longer in the nab-paclitaxel group than in the paclitaxel group both in the raw and matched dataset (12 vs. 7 months; P < 0.05). The median OS was not reached in the nab-paclitaxel group compared with 15 months in the paclitaxel group, with a trend toward prolongation. The most common toxicity was hematological adverse events, including grade 3-4 neutropenia, grade 3 anemia and thrombocytopenia in both groups and no statistical differences were observed between the groups (all P > 0.05).

CONCLUSION

Compared with paclitaxel plus platinum, nab-paclitaxel plus platinum may be an effective and tolerable option as first-line therapy for patients with metastatic or recurrent cervical cancer.

New mechanisms and biomarkers of lymph node metastasis in cervical cancer: reflections from plasma proteomics

OBJECTIVE

Lymph node metastasis (LNM) and lymphatic vasculature space infiltration (LVSI) in cervical cancer patients indicate a poor prognosis, but satisfactory methods for diagnosing these phenotypes are lacking. This study aimed to find new effective plasma biomarkers of LNM and LVSI as well as possible mechanisms underlying LNM and LVSI through data-independent acquisition (DIA) proteome sequencing.

METHODS

A total of 20 cervical cancer plasma samples, including 7 LNM-/LVSI-(NC), 4 LNM-/LVSI + (LVSI) and 9 LNM + /LVSI + (LNM) samples from a cohort, were subjected to DIA to identify differentially expressed proteins (DEPs) for LVSI and LNM. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed for DEP functional annotation. Protein-protein interaction (PPI) and weighted gene coexpression network analysis (WGCNA) were used to detect new effective plasma biomarkers and possible mechanisms.

RESULTS

A total of 79 DEPs were identified in the cohort. GO and KEGG analyses showed that DEPs were mainly enriched in the complement and coagulation pathway, lipid and atherosclerosis pathway, HIF-1 signal transduction pathway and phagosome and autophagy. WGCNA showed that the enrichment of the green module differed greatly between groups. Six interesting core DEPs (SPARC, HPX, VCAM1, TFRC, ERN1 and APMAP) were confirmed to be potential plasma diagnostic markers for LVSI and LNM in cervical cancer patients.

CONCLUSION

Proteomic signatures developed in this study reflected the potential plasma diagnostic markers and new possible pathogenesis mechanisms in the LVSI and LNM of cervical cancer.

Single-nucleus RNA sequencing and deep tissue proteomics reveal distinct tumour microenvironment in stage-I and II cervical cancer

BACKGROUND

Cervical cancer (CC) is the 3rd most common cancer in women and the 4th leading cause of deaths in gynaecological malignancies, yet the exact progression of CC is inconclusive, mainly due to the high complexity of the changing tumour microenvironment (TME) at different stages of tumorigenesis. Importantly, a detailed comparative single-nucleus transcriptomic analysis of tumour microenvironment (TME) of CC patients at different stages is lacking.

METHODS

In this study, a total of 42,928 and 29,200 nuclei isolated from the tumour tissues of stage-I and II CC patients and subjected to single-nucleus RNA sequencing (snRNA-seq) analysis. The cell heterogeneity and functions were comparatively investigated using bioinformatic tools. In addition, label-free quantitative mass spectrometry based proteomic analysis was carried out. The proteome profiles of stage-I and II CC patients were compared, and an integrative analysis with the snRNA-seq was performed.

RESULTS

Compared with the stage-I CC (CCI) patients, the immune response relevant signalling pathways were largely suppressed in various immune cells of the stage-II CC (CCII) patients, yet the signalling associated with cell and tissue development was enriched, as well as metabolism for energy production suggested by the upregulation of genes associated with mitochondria. This was consistent with the quantitative proteomic analysis that showed the dominance of proteins promoting cell growth and intercellular matrix development in the TME of CCII group. The interferon-α and γ responses appeared the most activated pathways in many cell populations of the CCI patients. Several collagens, such as COL12A1, COL5A1, COL4A1 and COL4A2, were found significantly upregulated in the CCII group, suggesting their roles in diagnosing CC progression. A novel transcript AC244205.1 was detected as the most upregulated gene in CCII patients, and its possible mechanistic role in CC may be investigated further.

CONCLUSIONS

Our study provides important resources for decoding the progression of CC and set the foundation for developing novel approaches for diagnosing CC and tackling the immunosuppressive TME.

SMOC2 promotes an epithelial-mesenchymal transition and a pro-metastatic phenotype in epithelial cells of renal cell carcinoma origin

Renal Cell Carcinoma (RCC) is the most common form of all renal cancer cases, and well-known for its highly aggressive metastatic behavior. SMOC2 is a recently described non-structural component of the extracellular matrix (ECM) that is highly expressed during tissue remodeling processes with emerging roles in cancers, yet its role in RCC remains elusive. Using gene expression profiles from patient samples, we identified SMOC2 as being significantly expressed in RCC tissue compared to normal renal tissue, which correlated with shorter RCC patient survival. Specifically, de novo protein synthesis of SMOC2 was shown to be much higher in the tubular epithelial cells of patients with biopsy-proven RCC. More importantly, we provide evidence of SMOC2 triggering kidney epithelial cells into an epithelial-to-mesenchymal transition (EMT), a phenotype known to promote metastasis. We found that SMOC2 induced mesenchymal-like morphology and activities in both RCC and non-RCC kidney epithelial cell lines. Mechanistically, treatment of RCC cell lines ACHN and 786-O with SMOC2 (recombinant and enforced expression) caused a significant increase in EMT-markers, -matrix production, -proliferation, and -migration, which were inhibited by targeting SMOC2 by siRNA. We further characterized SMOC2 activation of EMT to occur through the integrin β3, FAK and paxillin pathway. The proliferation and metastatic potential of SMOC2 overexpressing ACHN and 786-O cell lines were validated in vivo by their significantly higher tumor growth in kidneys and systemic dissemination into other organs when compared to their respective controls. In principle, understanding the impact that SMOC2 has on EMT may lead to more evidence-based treatments and biomarkers for RCC metastasis.

Secreted Protein Acidic and Rich in Cysteine as a Molecular Physiological and Pathological Biomarker

Secreted protein acidic and rich in cysteine (SPARC) is expressed in diverse tissues and plays roles in various biological functions and processes. Increased serum levels of SPARC or its gene overexpression have been reported following numerous physiological and pathological changes including injuries, exercise, regeneration, obesity, cancer, and inflammation. Such expression pattern interrelation between these biological changes and the SPARC expression/secretion points to it as a biomarker. This property could lead to a variety of potential applications ranging from mechanistic studies and animal model validation to the clinical and therapeutic evaluation of both disease prognosis and pharmacological agents.

Increased expression of ASRGL1 in invasive ductal carcinoma and its association with estrogen-progesterone receptor status of tumors

AIMS

Human asparaginase-like protein 1 (ASRGL1) is closely related to tumor growth. ASRGL1 can significantly promote cell proliferation and suppress apoptosis. To date, high levels of expression of ASRGL1 have been reported in various tumors, but the function of ASRGL1 in carcinogenesis is still not well understood. In this study, we aimed to immunohistochemically investigate the expression of ASRGL1 in non-neoplastic breast tissue and invasive ductal carcinoma.

METHODS AND RESULTS

ASRGL1 was evaluated immunohistochemically in 148 invasive ductal carcinomas and 105 nonneoplastic breast tissue samples to assess the impact on breast cancer development and its association with clinicopathologic features. ASRGL1 was observed positive in 63 (42.6%) and negative in 85 (57.4%) invasive ductal carcinoma. In nonneoplastic breast tissue, 24 (22.9%) cases were ASRGL1 positive and 81 (77.1%) were negative. A significant difference was observed between invasive ductal carcinoma and nonneoplastic breast tissue in terms of ASRGL1 expression, and ASRGL1 expression was increased in invasive ductal carcinoma (P = .001). Most estrogen receptor-negative tumors and progesterone receptor-negative tumors were also negative with ASRGL1 and the difference was significant (P = .006 and P = .001, respectively). The correlation between the ASRGL1 expression of the tumors and event-free survival or overall survival was not significant (P>.05).

CONCLUSIONS

ASRGL1 may play a role in increasing cell proliferation and breast cancer development. ASRGL-1 expression in breast cancer closely correlates with the hormone receptor status of the tumor. In breast cancer, ASRGL-1 expression does not contribute to predicting tumor behavior.

Sorafenib derivatives-functionalized gold nanoparticles confer protection against tumor angiogenesis and proliferation via suppression of EGFR and VEGFR-2

Sorafenib is a multi-kinase inhibitor that has been highlighted as a tumor suppressor due to its anti-proliferative and anti-angiogenic properties, whereas the clinical application of Sorafenib is restricted by the side effects it may cause. The past decade has witnessed the development of a series of sorafenib derivatives to improve the clinical performance of sorafenib. Gold nanoparticles (AuNPs) have been widely utilized in drug delivery systems due to their unique properties, including biocompatible nature, simple preparation, and easy surface modification. Herein, this study is aimed to investigate the anti-tumor effects of new sorafenib derivatives-capped gold nanoparticles (AuNPs-New Sor) in tumor formation and metastasis as well as the underlying mechanisms. Initially, new sorafenib derivatives were constructed and combined with AuNPs to form AuNPs-New Sor, and the properties of synthesized AuNPs-New Sor were identified in a mouse model of tumorigenesis. The effect of AuNPs-New Sor on tumor vascular normalization was investigated by assessing vascular permeability and perfusion rate. Next, we evaluated the effect of AuNPs-New Sor on migration and viability of tumor cells and human umbilical vein endothelial cells (HUVECs) as well as on HUVEC angiogenesis in vitro. A melanoma mouse model was further established for in vivo substantiation of the anti-tumor effect of AuNPs-New Sor. According to the results, AuNPs could deliver new sorafenib derivatives into tumor tissues and downregulate the expression of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor-2 (VEGFR-2), thereby suppressing tumor migration, EMT, and angiogenesis in vitro. In addition, AuNPs-New Sor displayed competitive anti-tumor activities in vivo. Taken together, AuNPs-New Sor may attenuate tumor development and angiogenesis through downregulation of EGFR and VEGFR-2.

Cellular senescence and tumor promotion: Role of the Unfolded Protein Response

Senescence is a cellular state which can be viewed as a stress response phenotype implicated in various physiological and pathological processes, including cancer. Therefore, it is of fundamental importance to understand why and how a cell acquires and maintains a senescent phenotype. Direct evidence has pointed to the homeostasis of the endoplasmic reticulum whose control appears strikingly affected during senescence. The endoplasmic reticulum is one of the sensing organelles that transduce signals between different pathways in order to adapt a functional proteome upon intrinsic or extrinsic challenges. One of these signaling pathways is the Unfolded Protein Response (UPR), which has been shown to be activated during senescence. Its exact contribution to senescence onset, maintenance, and escape, however, is still poorly understood. In this article, we review the mechanisms through which the UPR contributes to the appearance and maintenance of characteristic senescent features. We also discuss whether the perturbation of the endoplasmic reticulum proteostasis or accumulation of misfolded proteins could be possible causes of senescence, and-as a consequence-to what extent the UPR components could be considered as therapeutic targets allowing for the elimination of senescent cells or altering their secretome to prevent neoplastic transformation.

Pan-Cancer Analyses Reveal Prognostic Value of Osteomimicry Across 20 Solid Cancer Types

Background

Osteomimicry of cancer cells had been widely reported in prostate cancer and breast cancer. However, the prognostic value of osteomimicry in various cancer types remained unclear. We hypothesized that osteomimicry would result in remodeling of the tumor microenvironment and was eligible to predict patient prognosis.

Methods

A comprehensive transcriptomic analysis of the osteomimicry, which was characterized by mRNA expression of SPARC, SPP1, and BGLAP, across 20 solid tumors (7564 patients) using RNA-seq data from The Cancer Genome Atlas (TCGA) was conducted. Samples of each cancer type were classified into subgroups (high vs. low) based on median value of osteomimetic markers, the associations of these markers with clinical outcomes, immune cell infiltration and immune checkpoints expression were explored.

Results

Each osteomimetic marker harbored prognostic value in the pan-cancer analyses [SPARC: hazard ratio (HR) = 1.10, p = 0.028; SPP1: HR = 1.25, p < 0.001; BGLAP: HR = 1.13, p = 0.005]. Patients with high expression of all the three genes also had significantly unfavorable survival (HR = 1.61, p < 0.0001) compared with those of low expression. Correlation analyses demonstrated that osteomimicry was closely related to tumor purity, dendritic cells (DC) infiltration and expression of immune checkpoints.

Conclusion

Osteomimicry had prognostic value in various cancer types and the underlying mechanism might correlate to the trapping and dysfunction of DCs in the tumor microenvironment, revealing the potential of osteomimicry as a target of immunotherapy.

Low Levels of SPARC are Associated with Tumor Progression and Poor Prognosis in Human Endometrial Carcinoma

Background

SPARC (secreted protein acidic and rich in cysteine), also known as osteonectin, BM-40, and 43 K protein, is a matricellular protein associated with various tumor progressions. The aim of this research was to investigate the prognostic value of SPARC in endometrial carcinoma (EC) and its function in cancer cell invasion and metastasis.

Methods

From both mRNA and protein levels, SPARC expression in normal endometrial tissue and EC tissue, normal endometrial cells and 4 EC cell lines (KLE, HEC-1A, HEC-1B, Ishikawa) were evaluated by immunohistochemistry (IHC) or immunocytochemistry (ICC), quantitative real-time PCR (qRT-PCR) and Western blotting. RNA interference mediated by lentivirus was performed to get the stable SPARC down-expressing cells. The functional analysis techniques in vitro and in vivo were used to detect the effects of SPARC knockdown on EC cell proliferation, apoptosis, invasion and metastasis.

Results

The expressions of SPARC in EC tissues and cells were much lower than those in normal endometrial cells and tissues; meanwhile, its low expression was closely related to the malignant clinicopathological characteristics of EC. SPARC knockdown could inhibit apoptosis, promote the process of EMT and improve the proliferation and invasion capacities of EC cells in vitro and in vivo.

Conclusion

The low expression of SPARC was detected in EC tissues and cells, which was positively correlated with the poor prognosis of EC patients. SPARC acted as a tumor suppressor gene that hindered EC progression, which proposed a new therapeutic strategy for EC treatment.

The Matrix Revolution: Matricellular Proteins and Restructuring of the Cancer Microenvironment

The extracellular matrix (ECM) surrounding cells is indispensable for regulating their behavior. The dynamics of ECM signaling are tightly controlled throughout growth and development. During tissue remodeling, matricellular proteins (MCP) are secreted into the ECM. These factors do not serve classical structural roles, but rather regulate matrix proteins and cell-matrix interactions to influence normal cellular functions. In the tumor microenvironment, it is becoming increasingly clear that aberrantly expressed MCPs can support multiple hallmarks of carcinogenesis by interacting with various cellular components that are coupled to an array of downstream signals. Moreover, MCPs also reorganize the biomechanical properties of the ECM to accommodate metastasis and tumor colonization. This realization is stimulating new research on MCPs as reliable and accessible biomarkers in cancer, as well as effective and selective therapeutic targets.

Secreted protein acidic and rich in cysteine promotes epithelial-mesenchymal transition of hepatocellular carcinoma cells and acquisition of cancerstem cell phenotypes

BACKGROUND AND AIM

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein that plays a significant role in tumor development. SPARC has been indicated that promotes tumorigenesis, metastasis, and poor prognosis in prostate cancer and lung cancer. Therefore, we sought to investigate the molecular mechanisms of SPARC in regulating hepatocellular carcinoma (HCC).

METHODS

We used spheroids cultured in serum-free culture medium to obtain liver cancer stem cells. Flow cytometric analysis was performed to investigate percentage of CD133⁺ cells in liver cancer cells. Real-time polymerase chain reaction and western blot were used to assess gene expression in cell lines. Transwell and wound healing assays were performed to indicate cell migration of HCC.

RESULTS

Secreted protein acidic and rich in cysteine was upregulated in spheres formation in HCC cells. Overexpression of SPARC enhanced the ability to form tumor spheres and increased CD133 and Oct4 expressions. Besides, SPARC promoted the migration and epithelial-mesenchymal transition in HCC cells. Importantly, SPARC overexpression stimulated the formation of subcutaneous tumors in nude mice.

CONCLUSIONS

Our findings suggest that SPARC overexpression promotes tumor growth, inducing epithelial-mesenchymal transition and acquisition of a stem cell phenotype. What is more, research elucidating the biological mechanisms of SPARC may be beneficial to liver cancer treatment.

SPARC promotes the proliferation and metastasis of oral squamous cell carcinoma by PI3K/AKT/PDGFB/PDGFRβ axis

Oral squamous cell carcinoma (OSCC) is a highly lethal cancer in the world, and the prognosis of OSCC is poor with a 60% 5-year survival rate in recent decades. Here, we introduced a novel secretory and acid glycoprotein with cysteine rich (secreted protein acidic and rich in cysteine, SPARC), which is correlated with the worst pattern of invasion (WPOI) and prognosis of OSCC. SPARC expression levels were measured in OSCC tissues and normal tissues using quantitative polymerase chain reaction and immunohistochemistry. The influence of SPARC on cell proliferation was examined by cell counting kit-8, colony formation, and Edu tests. Then, the effect of SPARC on the metastasis of OSCC cells was detected by wound healing and transwell migration assays. Next, the biologic characteristics of SPARC shared by STRING were analyzed. Furthermore, the underlying mechanisms were confirmed by western blot analysis. SPARC revealed higher expression in OSCC tissues than nontumor tissues. Higher SPARC expression was correlated with poorer tumor differentiation, poorer WPOI pattern, and significantly and shorter overall survival. Knockdown SPARC significantly restrained OSCC cell growth, migration, and invasion. In addition, bioinformatics analysis found SPARC had a coexpression network with the platelet-derived growth factor-B (PDGFB) and PI3K/AKT signaling pathways with minimal false discovery rate. Furthermore, SPARC promotes OSCC cells metastasis by regulating the expressions of PDGFB, PDGFRβ, p-PDGFRβ , and the PI3K/AKT pathway. Higher SPARC expression was positively correlated with poor WPOI and differentiation in OSCC. SPARC activates the PI3K/AKT/PDGFB/PDGFRβ axis to promote proliferation and metastasis by OSCC cell lines. Therefore, SPARC may be a potential therapeutic target for patients with OSCC.

Association of low expression of E-cadherin and β-catenin with the progression of early stage human squamous cervical cancer

The precise involvement and mechanisms of human papilloma virus type 16 (HPV16) in epithelial-mesenchymal transition (EMT) of cervical intraepithelial neoplasia (CIN) and squamous cervical cancer (SCC) remain unknown. The present study aimed to examine the expression of EMT indicators and their association with HPV16 in CIN and early stage SCC, and their prognostic value in early stage SCC. The expression levels of E-cadherin, N-cadherin, β-catenin, vimentin, and fibronectin were determined by immunohistochemistry in 40 patients with normal uterine cervix, 22 patients with CIN1, 60 patients with CIN2-3, and 86 patients with SCC, stage Ia-IIa, according to the International Federation of Gynecology and Obstetrics. The expression of the epithelial indicators E-cadherin and β-catenin gradually declined, and the mesenchymal indicators N-cadherin, vimentin, and fibronectin increased with progression of the cervical lesions (P<0.05). Patients with SCC with lymph node metastasis, parametrial invasion, negative E-cadherin, and negative β-catenin expression had shorter overall survival (P=0.001, P=0.015, P=0.014, and P=0.043, respectively) and disease-free survival (P=0.002, P=0.021, P=0.025, and P=0.045, respectively) time. Multivariate survival analysis indicated that lymph node metastasis [Hazard ratio (HR)=3.544; P=0.010], parametrial invasion (HR=2.014; P=0.007) and E-cadherin expression (HR=0.163; P<0.001) were independently associated with overall survival, but also with disease-free survival (HR=3.612, P=0.009; HR=1.935, P=0.011; HR=0.168, P<0.001, respectively). In patients with CINs, HPV16 infection was negatively correlated with the expression of E-cadherin, and positively correlated with the expression of N-cadherin, vimentin, and fibronectin. EMT occurs during the progression of CINs to early stage SCC, and is associated with HPV16 infection in CINs. Lymph node metastasis and parametrial invasion are poor prognostic factors for SCC, while positive E-cadherin expression may serve as a protective prognostic factor for SCC.

Apoptotic signaling in salivary mucoepidermoid carcinoma

BACKGROUND

Mucoepidermoid carcinoma is the most common malignant tumor of salivary glands. Apoptosis plays an important role in organogenesis of glandular structures, and aberrations of apoptotic mechanisms is associated with a wide array of pathologic conditions.

METHODS

The immunoexpression of proteins associated with apoptosis and proliferation was evaluated in 40 mucoepidermoid carcinoma cases.

RESULTS

Par-4, Survivin, MUC1, PHLDA1, Fas, and Ki-67 were predominantly expressed in mucoepidermoid carcinoma. FasL was rarely expressed, and Caspase-3 expression was observed in almost 50% of the cases. SPARC expression was associated with low-grade tumors, and Ki-67 expression was associated with lymph node metastasis. Expression of Fas and decreased expression of Ki-67 and Caspase-3 were associated with better overall cancer-specific survival rates.

CONCLUSIONS

The association of SPARC and Ki-67 expression with pathological features and the association of Fas, Caspase-3, and Ki-67 with survival probabilities suggest that these proteins may be useful prognostic markers for mucoepidermoid carcinoma.

Cancer Theranostic Applications of Albumin-Coated Tobacco Mosaic Virus Nanoparticles

Nanotechnology holds great promise in cancer drug delivery, and of particular interest are theranostic approaches in which drug delivery and imaging are integrated. In this work, we studied and developed the plant virus tobacco mosaic virus (TMV) as a platform nanotechnology for drug delivery and imaging. Specifically, a serum albumin (SA)-coated TMV formulation was produced. The SA coating fulfils two functions: SA provides a stealth coating for enhanced biocompatibility; it also acts as a targeting ligand enabling efficient tumor accumulation of SA-TMV versus TMV in mouse models of breast and prostate cancer. We demonstrate drug delivery of the chemotherapy doxorubicin (DOX); TMV-delivered DOX outperformed free DOX, resulting in significant delayed tumor growth and increased survival. Furthermore, we demonstrated the ability of SA-coated TMV loaded with chelated Gd(DOTA) for magnetic resonance imaging detection of tumors. In the future, we envision the application of such probes as theranostic, where first imaging is performed to assess whether the nanoparticles are effective at targeting a particular patient tumor. If targeting is confirmed, the therapeutic would be added and treatment can begin. The combination of imaging and therapy would allow to monitor disease progression and therefore inform about the effectiveness of the drug delivery approach.

Genomic and expression profiling reveal molecular heterogeneity of disseminated tumor cells in bone marrow of early breast cancer

Detection of disseminated tumor cells (DTCs) in bone marrow is an established negative prognostic factor. We isolated small pools of (~20) EPCAM-positive DTCs from early breast cancer patients for genomic profiling. Genome-wide copy number profiles of DTC pools (n = 45) appeared less aberrant than the corresponding primary tumors (PT, n = 16). PIK3CA mutations were detected in 26% of DTC pools (n = 53), none of them were shared with matched PTs. Expression profiling of DTC pools (n = 30) confirmed the upregulation of EPCAM expression and certain oncogenes (e.g., MYC and CCNE1), as well as the absence of hematopoietic features. Two expression subtypes were observed: (1) luminal with dual epithelial-mesenchymal properties (high ESR1 and VIM/CAV1 expression), and (2) basal-like with proliferative/stem cell-like phenotype (low ESR1 and high MKI67/ALDH1A1 expression). We observed high discordance between ESR1 (40%) and ERRB2 (43%) expression in DTC pools vs. the clinical ER and HER2 status of the corresponding primary tumors, suggesting plasticity of biomarker status during dissemination to the bone marrow. Comparison of expression profiles of DTC pools with available data from circulating tumor cells (CTCs) of metastatic breast cancer patients revealed gene expression signatures in DTCs that were unique from those of CTCs. For example, ALDH1A1, CAV1, and VIM were upregulated in DTC pools relative to CTCs. Taken together, analysis of pooled DTCs revealed molecular heterogeneity, possible genetic divergence from corresponding primary tumor, and two distinct subpopulations. Validation in larger cohorts is needed to confirm the presence of these molecular subtypes and to evaluate their biological and clinical significance.

SPARC acts as a mediator of TGF-β1 in promoting epithelial-to-mesenchymal transition in A549 and H1299 lung cancer cells

Migration and metastasis of tumor cells greatly contributes to the failure of cancer treatment. Recently, the extracellular protein secreted protein acidic and rich in cysteine (SPARC) has been reported closely related to tumorigenesis. Some articles have suggested that SPARC promoted metastasis in several highly metastatic tumors. However, there are also some studies shown that SPARC acted as an antitumor factor. SPARC-induced epithelial-to-mesenchymal transition (EMT) in melanoma cells and promoted EMT in hepatocellular carcinoma. Therefore, the role of SPARC in tumorigenesis and its relationship with EMT is still unclear. In this study, we investigated the expression change of SPARC in A549 and H1299 lung cancer cells undergoing EMT process. Our study indicated that SPARC was upregulated in A549 and H1299 cells EMT process. We further investigated the function of SPARC on proliferation, migration, and EMT process of A549 and H1299 cells. Overexpression of SPARC promoted the migration and EMT of A549 and H1299 cells. Knockdown SPARC inhibited the EMT of A549 cells. Overexpression of SPARC induced the increased expression of p-Akt and P-ERK. Furthermore, exogenous SPARC peptide promoted transforming growth factor (TGF)-β1-induced EMT of A549 and H1299 cells. SPARC knockdown partially eliminated TGF-β1 function in inducing EMT of A549 cells. SPARC follistatin-like functional domain reduced the expression of E-cadherin, but had no effect on the expression of p-Akt and p-ERK. In conclusion, we elucidated that SPARC contributes to tumorigenesis by promoting migration and EMT of A549 and H1299 lung cancer cells. These results will provide some new suggestion for lung cancer treatment. © 2018 BioFactors, 44(5):453-464, 2018.

Roles of Albumin-Binding Proteins in Cancer Progression and Biomimetic Targeted Drug Delivery

Nutrient transporters have attracted significant attention for their promising application in biomimetic delivery. Due to the active consumption of nutrients, cancer cells generally overexpress nutrient transporters to meet their increased need for energy and materials. For example, albumin-binding proteins (ABPs) are highly overexpressed in malignant cells, stromal cells, and tumor vessel endothelial cells responsible for albumin uptake. ABP (e.g., SPARC) is a promising target for tumor-specific drug delivery, and albumin has been widely used as a biomimetic delivery carrier. Apart from the transportation function, ABPs are closely associated with neoplasia, invasion, and metastasis. Herein, a summary of the roles of ABP in cancer progression and the application of albumin-based biomimetic tumor-targeted delivery through the ABP pathway is presented.

miR-211 inhibits proliferation, invasion and migration of cervical cancer via targeting SPARC

Cervical cancer remains one of the most frequent gynecological malignancies among females around the world. Therefore, fully understanding the molecular mechanisms underlying the progression of cervical cancer may be critical for the development of effective therapeutic strategies against cervical cancer. The object was to evaluate the potential effect of miR-211 and verify its influence on the function of secreted protein acidic and rich in cysteine (SPARC) in cervical cancer. It was demonstrated that miR-211 was downregulated in cervical cancer cell lines (HeLa and C33A) and cervical cancer specimens, while SPARC expression level was higher in tumor tissues. We also revealed miR-211 upregulated expression could inhibit cells proliferation, migration and invasion in vivo. SPARC was confirmed as a direct and functional target of miR-211 and the inverse relationship between them was also observed. The results of the present study suggest that miR-211 reduced cancer growth, migration and invasion, and suppresses the SPARC expression in cervical cancer. This newly identified miR-211 may provide further insight into the progression and offers a promising target for cervical cancer therapy.

Cervical cancer stem-like cells: systematic review and identification of reference genes for gene expression

Cervical cancer is the fourth most common cancer affecting women worldwide. Among many factors, the presence of cancer stem cells, a subpopulation of cells inside the tumor, has been associated with a worse prognosis. Considering the importance of gene expression studies to understand the biology of cervical cancer stem cells (CCSC), this work identifies stable reference genes for cervical cancer cell lines SiHa, HeLa, and ME180 as well as their respective cancer stem-like cells. A literature review was performed to identify validated reference genes currently used to normalize RT-qPCR data in cervical cancer cell lines. Then, cell lines were cultured in regular monolayer or in a condition that favors tumor sphere formation. RT-qPCR was performed using five reference genes: ACTB, B2M, GAPDH, HPRT1, and TBP. Stability was assessed to validate the selected genes as suitable reference genes. The evaluation validated B2M, GAPDH, HPRT1, and TBP in these experimental conditions. Among them, GAPDH and TBP presented the lowest variability according to the analysis by Normfinder, Bestkeeper, and ΔCq methods, being therefore the most adequate genes to normalize the combination of all samples. These results suggest that B2M, GAPDH, HPRT1, and TBP are suitable reference genes to normalize RT-qPCR data of established cervical cancer cell lines SiHa, HeLa, and ME180 as well as their derived cancer stem-like cells. Indeed, GAPDH and TBP seem to be the most convenient choices for studying gene expression in these cells in monolayers or spheres.

miR-222 knockdown suppresses epithelial-to-mesenchymal transitionin human oral squamous cell carcinoma

Tumor metastasis is the main cause of death in patients with oral squamous cell carcinoma (OSCC). Epithelial-to-mesenchymal transition (EMT) is potentially associated with metastasis and histological grading in OSCC. Therefore, the discovery of new strategies to inhibit EMT is potentially valuable for the development of therapies for OSCC. In our previous study, we found that miR-222, which is up-regulated in OSCC, regulates the biological behavior of OSCC cells by targeting the p53-upregulated modulator of apoptosis (PUMA); however, the effect of miR-222 on TGF-β1-induced EMT in OSCC cells is unclear. In this study, OSCC cell lines CAL-27 and Tca-8113 were incubated with 5 ng/ml of TGF-β1 to inhibit the expression of E-cadherin, promote the expression of N-cadherin, vimentin, and α-SMA and stimulate achange in cell shape convert from a "cuboidal" epithelial structure into an elongated mesenchymal shape. We found that the expression of miR-222 was up-regulated during TGF-β1-induced EMT in OSCC cells. In addition, miR-222 knockdown reversed TGF-β1-induced EMT by targeting PUMA. Our findings indicate that miR-222 plays an important role in OSCC, potentially serving as a novel therapeutic target for the treatment of OSCC.

The Roles of Matricellular Proteins in Oncogenic Virus-Induced Cancers and Their Potential Utilities as Therapeutic Targets

Matricellular proteins differ from other classical extracellular matrix proteins; for instance, they are transiently expressed as soluble proteins rather than being constitutively expressed in pathological conditions, such as acute viral infections. Accumulating studies have revealed that matricellular proteins, including osteopontin and tenascin-C, both of which interact with integrin heterodimers, are involved in inflammatory diseases, autoimmune disorders, and cancers. The concentrations of these matricellular proteins are elevated in the plasma of patients with certain types of cancers, indicating that they play important roles in oncogenesis. Chronic viral infections are associated with certain cancers, which are distinct from non-viral cancers. Viral oncogenes play critical roles in the development and progression of such cancers. It is vital to investigate the mechanisms of tumorigenesis and, particularly, the mechanism by which viral proteins induce tumor progression. Viral proteins have been shown to influence not only the viral-infected cancer cells, but also the stromal cells and matricellular proteins that constitute the extracellular matrix that surrounds tumor tissues. In this review, we summarize the recent progress on the involvement of matricellular proteins in oncogenic virus-induced cancers to elucidate the mechanism of oncogenesis and consider the possible role of matricellular proteins as therapeutic targets in virus-induced cancers.

Correlation between secreted protein acidic and rich in cysteine protein expression and the prognosis of postoperative patients exhibiting esophageal squamous cell carcinoma

The aim of the present study was to investigate the association between the expression level of secreted protein acidic and rich in cysteine (SPARC) and the prognosis of postoperative patients with esophageal squamous cell carcinoma (ESCC). The expression level of SPARC was detected in the 89 ESCC tissue cases and 100 healthy esophageal mucosa cases, which served as the controls. Immunohistochemistry and reverse transcription‑polymerase chain reaction (RT‑PCR) were employed to evaluate the SPARC expression in cases with ESCC. RT‑PCR demonstrated that the positive rates of SPARC mRNA expression in ESCC were 71.91% (64/89). The positive rates of normal esophageal mucosa mRNA expression were 15.00% (15/100), which were significantly lower than that in the ESCC tissue samples. The difference was statistically significant (P<0.001). Immunohistochemical staining indicated that the positive expression rate of SPARC protein in the ESCC tissue samples was significantly higher than that in the esophageal mucosa tissue samples (65.17 vs. 8.00%; P<0.001). The expression of SPARC protein was negatively correlated with lymph node metastasis (P<0.05), which was not associated with the pathologic gross morphology, tumor differentiation degree or other clinical features. The survival of patients with ESCC was not associated with the expression level of SPARC protein (P>0.05), but was associated with the tumor location (P<0.05), differentiation (P<0.001) and staging (P<0.05). Thus, SPARC mRNA and protein were highly expressed in ESCC, and negatively correlated with lymph node metastasis, which was not associated with postoperative survival of ESCC patients. Thus, detection of SPARC mRNA and protein expression levels may facilitate early diagnosis and prognosis assessment of ESCC.

Self-Targeting, Immune Transparent Plasma Protein Coated Nanocomplex for Noninvasive Photothermal Anticancer Therapy

Cancer cells exhibit specific physiological differences compared to normal cells. Most surface membranes of cancer cells are characterized by high expression of given protein receptors, such as albumin, transferrin, and growth factors that are also present in the plasma of patients themselves, but are lacking on the surface of normal cells. These distinct features between cancer and normal cells can serve as a niche for developing specific treatment strategies. Near-infrared (NIR)-light-triggered therapy platforms are an interesting novel avenue for use in clinical nanomedicine. As a photothermal agent, conducting polymer nanoparticles, such as polypyrrole (PPy), of great NIR light photothermal effects and good biocompatibility, show promising applications in cancer treatments through the hyperthermia mechanism. Autologous plasma proteins coated PPy nanoparticles for hyperthermia therapy as a novel core technology platform to treat cancers through secreted protein acid and rich in cysteine targeting are developed here. This approach can provide unique features of specific targeting toward cancer cell surface markers and immune transparency to avoid recognition and attack by defense cells and achieve prolonged circulation half-life. This technology platform unveils new clinical options for treatment of cancer patients, supporting the emergence of innovative clinical products.

Smoc2 potentiates proliferation of hepatocellular carcinoma cells via promotion of cell cycle progression

AIM

To determine the influence of Smoc2 on hepatocellular carcinoma (HCC) cell proliferation and to find a possible new therapeutic target for preventing HCC progression.

METHODS

We detected expression of Smoc2 in HCC tissues and corresponding non-tumor liver (CNL) tissues using PCR, western blot, and immunohistochemistry methods. Subsequently, we down-regulated and up-regulated Smoc2 expression using siRNA and lentivirus transfection assay, respectively. Then, we identified the effect of Smoc2 on cell proliferation and cell cycle using CCK-8 and flow cytometry, respectively. The common cell growth signaling influenced by Smoc2 was detected by western blot assay.

RESULTS

The expression of Smoc2 was significantly higher in HCC tissues compared with CNL tissues. Overexpression of Smoc2 promoted HCC cell proliferation and cell cycle progression. Down-regulation of Smoc2 led to inhibition of cell proliferation and cell cycle progression. Smoc2 had positive effect on ERK and AKT signaling.

CONCLUSION

Smoc2 promotes the proliferation of HCC cells through accelerating cell cycle progression and might act as an anti-cancer therapeutic target in the future.

Tumor-associated macrophages in human breast cancer parenchyma negatively correlate with lymphatic metastasis after neoadjuvant chemotherapy

Breast cancer is the leading cause of cancer death in women worldwide with high morbidity and mortality. Tumor-associated macrophages (TAM) are major innate immune cells in the tumor microenvironment controlling primary tumor growth and metastasis. Neoadjuvant chemotherapy (NACT) is a conventional pre-operative treatment for breast cancer. In the present study we examined the distribution of TAM in five distinct intratumoral morphological compartments of human breast cancer and their correlation with clinical parameters after NACT. Our data indicated that CD68+ but not stabilin-1+ TAM in areas with parenchymal elements negatively correlate with lymphatic metastasis after NACT. However, in cases where lymphatic metastases were detected (28 out of 50 analyzed samples) both amount of CD68+ and stabilin-1+ macrophages in the areas with coarse fibrous stroma directly correlated with the number of positive lymph nodes. In patients with complete response to the preoperative NACT the average score of CD68 expression in the areas with coarse fibrous stroma was lower compared with cases of a partial response and stable disease. We concluded that function of TAM after NACT depends on their intratumoral localization and local tumor microenvironment which plays an important role in polarization of macrophages towards tumor-suppressive or tumor-supportive types.