Maspin expression is characteristic for cisplatin-sensitive ovarian cancer cells and for ovarian cancer cases of longer survival rates

Hypoxia-induced Maspin Expression Affects the Prognosis of Ovarian Clear Cell Carcinoma

BACKGROUND/AIM

To investigate the role of the expression of hypoxia-related genes on the prognosis of ovarian clear cell carcinoma (OCCC).

MATERIALS AND METHODS

Basal mRNA levels of eight hypoxia-related genes were compared. Cell viability was assayed after treating ES-2 cells under hypoxic conditions. The mRNA and protein levels were evaluated after the induction of hypoxia and administration of increased doses of N-acetylcysteine (NAC). Finally, the prognostic role of their expression levels was evaluated in 61 patients with OCCC.

RESULTS

The mRNA and protein levels of maspin increased gradually with the induction of hypoxia. Maspin protein expression decreased after treatment with paclitaxel and NAC. High expression of maspin was related to poor progression-free and overall survival in patients with OCCC (adjusted hazard ratios, 3.97 and 7.47; 95% confidence intervals=1.34-11.81, and 1.98-28.13).

CONCLUSION

High expression of maspin induced by hypoxia might be associated with poor prognosis of OCCC.

Prognostic role of maspin expression in patients with cervical dysplasia and cervical cancer

AIM

Mammary serine protease inhibitor (maspin) acts as a tumor suppressor through the inhibition of cancer cell invasion and metastasis. Paradoxically, maspin levels are increased in some types of malignant cells. The aim of this study was to investigate the maspin expression in cervical dysplasia and cervical cancer, and to analyze its' relation with survival.

METHODS

Maspin expression was detected by immunohistochemistry using labeled streptavidin biotin method to determine cytoplasmic and nuclear maspin expressions in cervical intraepithelial neoplasia grade 1 (CIN1), cervical intraepithelial neoplasia grade 2 (CIN2), cervical intraepithelial neoplasia grade 3 (CIN3) and cervical cancer.

RESULTS

A total of 89 patients with CIN (29 cases of CIN1, 30 cases of CIN2 and 30 cases of CIN3), and 27 patients with cervical cancer were included to the study. 7.8% of the patients with CIN had maspin staining positivity. On the other hand maspin staining was positive in 20 of 27 patients (74.1%) with cervical carcinoma (P = 0.001). Of these patients 20 (100%) had cytoplasmic, and 8 (40%) had nuclear maspin staining positivity. Cytoplasmic maspin immunoreactive scores were found to be significantly higher in carcinoma group when compared to the patients with CIN1/3 (respectively; P = 0.01, P = 0.02). No difference was noted for nuclear maspin expression. Significant overall survival advantage was detected for patients with nuclear maspin staining (P = 0.03).

CONCLUSION

The current study shows that nuclear maspin expression is related with better overall survival in cervical cancer. Maspin staining can be a useful diagnostic marker to discriminate cervical intraepithelial neoplasia from cervical carcinoma.

Subcellular expression of maspin – from normal tissue to tumor cells

Maspin or SerpinB5, a member of the serine protease inhibitor family, was shown to function as a tumor suppressor, especially in carcinomas. It seems to inhibit invasion, tumor cells motility and angiogenesis, and promotes apoptosis. Maspin can also induce epigenetic changes such as cytosine methylation, de-acetylation, chromatin condensation, and histone modulation. In this review, a comprehensive synthesis of the literature was done to present maspin function from normal tissues to pathologic conditions. Data was sourced from MEDLINE and PubMed. Study eligibility criteria included: Published in English, between 1994 and 2019, specific to humans, and with full-text availability. Most of the 118 studies included in the present review focused on maspin immunostaining and mRNA levels. It was shown that maspin function is organ-related and depends on its subcellular localization. In malignant tumors, it might be downregulated or negative (e.g., carcinoma of prostate, stomach, and breast) or upregulated (e.g., colorectal and pancreatic tumors). Its subcellular localization (nuclear vs cytoplasm), which can be proved using immunohistochemical methods, was shown to influence both tumor behavior and response to chemotherapy. Although the number of maspin-related papers increased, the exact role of this protein remains unknown, and its interpretation should be done with extremely high caution.

Maspin enhances cisplatin chemosensitivity in bladder cancer T24 and 5637 cells and correlates with prognosis of muscle-invasive bladder cancer patients receiving cisplatin based neoadjuvant chemotherapy

Background

Maspin, a non-inhibitory member of the serine protease inhibitor superfamily, has been characterized as a tumor suppressor gene in multiple cancer types. Chemotherapeutic insensitivity is one of major obstacles to effectively treating muscle invasive bladder cancer (MIBC). This study was conducted to investigate the role and probable mechanism of Maspin enhancing cisplatin chemosensitivity of bladder cancer in vitro and MIBC patients.

Methods

Maspin expression was quantified by qRT-PCR in two MIBC cell lines (T24 and 5637). After successful established Maspin overexpression model by lipidosome transfection, MTT and cell apoptosis assay were used to assess the MIBC’s cisplatin sensitivity. Western blot method was used to test PI3K/ AKT/mTOR signal passway and apoptosis related molecules Caspase3 and Bcl-2. Additionally, we evaluated Maspin expression and prognosis in 62 MIBC cases who underwent cisplatin based neoadjuvant chemotherapy (NACT) using immunohistochemistry.

Result

Upregulate Maspin expression could enhance the chemosensitivity induced by cisplatin in T24 and 5637 cell lines. The cell viability, cloning ability and IC50 were reduced while apoptosis rate was upregulated when cells were transfected Maspin. Phospho(p)-AKT, PI3K, mTOR, and Bcl-2 expression were significantly decreased, whereas Caspase3 was greatly increased in the Maspin group. In the clinic study, there was significant correlation between Maspin expression and overall survival (OS) and progression-free survival (PFS) rate in MIBC patients who received cisplatin based NACT.

Conclusion

Maspin could enhance cisplatin chemosensitivity in T24 and 5637 cell lines. Its expression correlated with prognosis of MIBC patients who received cisplatin based neoadjuvant chemotherapy.

Mammary serine protease inhibitor and CD138 immunohistochemical expression in ovarian serous and clear cell carcinomas

This study aims to investigate the immunohistochemical expression of mammary serine protease inhibitor (maspin) and CD138 in primary ovarian high-grade serous carcinomas (HGSC) as compared to low-grade serous carcinomas (LGSC) and clear cell carcinomas and investigate if the studied markers have a correlation to International Federation of Gynaecology and Obstetrics (FIGO) stage, Ki67 proliferation index, and to each other. Maspin cellular location varied significantly between studied groups with only nuclear expression seen in 46.7 % of LGSC group, mixed nuclear and cytoplasmic in 13.3, 28.6, and 20 % of LGSC, HGSC, and clear cell carcinoma, respectively, and was only cytoplasmic in 26.7, 71.4, and 80 % of LGSC, HGSC, and clear cell carcinoma, respectively. Mean maspin and CD138 counts were significantly higher in HGSC and clear cell carcinoma compared to LGSC. Both maspin and CD138 scores varied significantly between studied groups and were positively correlated with adverse prognostic factors in studied carcinomas including FIGO stage and Ki67 proliferation index. Besides, both maspin and CD138 had significant correlation to each other. These findings suggest that epithelial cytoplasmic expression of maspin and CD138 may have a significant role in tumorigenesis in ovarian high-grade serous carcinomas and clear cell carcinomas; these markers may regulate tumor cell proliferation, and their significant correlation to each other may suggest that CD138 probably induces maspin expression to protect tumor growth factors from being lysed by proteolytic enzymes.

BRCA1 185delAG Mutation Enhances Interleukin-1β Expression in Ovarian Surface Epithelial Cells

Familial history remains the strongest risk factor for developing ovarian cancer (OC) and is associated with germline BRCA1 mutations, such as the 185delAG founder mutation. We sought to determine whether normal human ovarian surface epithelial (OSE) cells expressing the BRCA1 185delAG mutant, BRAT, could promote an inflammatory phenotype by investigating its impact on expression of the proinflammatory cytokine, Interleukin-1β (IL-1β). Cultured OSE cells with and without BRAT were analyzed for differential target gene expression by real-time PCR, western blot, ELISA, luciferase reporter, and siRNA assays. We found that BRAT cells expressed increased cellular and secreted levels of active IL-1β. BRAT-expressing OSE cells exhibited 3-fold enhanced IL-1β mRNA expression, transcriptionally regulated, in part, through CREB sites within the (−1800) to (−900) region of its promoter. In addition to transcriptional regulation, BRAT-mediated IL-1β expression appears dualistic through enhanced inflammasome-mediated caspase-1 cleavage and activation of IL-1β. Further investigation is warranted to elucidate the molecular mechanism(s) of BRAT-mediated IL-1β expression since increased IL-1β expression may represent an early step contributing to OC.

VEGF-C inhibition reverses resistance of bladder cancer cells to cisplatin via upregulating maspin

The aim of the current study was to elucidate the association between vascular endothelial growth factor C (VEGF-C) and resistance of bladder cancer cells to cisplatin and the underlying mechanism involving maspin. A total of 32 bladder cancer tissue samples from patients (18 males and 14 females with an average age of 65.9 years) were collected from the Fifth Affiliated Hospital of Zhengzhou University (Zhengzhou, China). All patients had undergone cisplatin-based combination chemotherapy. In addition, the BIU87 human bladder cancer cell line was cultured and a cisplatin-resistant subline (BIU87-CisR) was established by continuous exposure to cisplatin. The mRNA expression levels of VEGF-C and maspin in tissue samples, BIU87 cells and BIU87-CisR cells were analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Targeted inhibition of VEGF-C in BIU87-CisR cells was performed using small interfering (si)RNA technology and the alteration in levels of maspin was confirmed by RT-qPCR and western blot analysis. siRNA-treated and -untreated BIU87-CisR cells were divided into the following four groups: Control group (no drug treatment), 3 μM cisplatin treated group, 3 μM cisplatin + siRNA treated group and the siRNA treated group. Cell viability following treatment in each group was evaluated by the cell counting kit 8 assay. The cell cycle and apoptotic rate of BIU87-CisR cells was analyzed by propidium iodide (PI) staining and Annexin V-PI double staining with flow cytometry. Furthermore, pcDNA-maspin transfected BIU78-CisR cells were used to establish the effect of maspin on the sensitivity to cisplatin. VEGF-C expression in chemoresistant patients and BIU87-CisR cells was significantly increased compared with chemosensitive patients and normal BIU87 cells, respectively. By contrast, maspin levels were lower in chemoresistant patients and BIU87-CisR cells. Subsequent to VEGF-C inhibition, maspin expression was markedly increased. Cisplatin (3 μM) resulted in moderate proliferation inhibition of BIU87-CisR cells without siRNA pretreatment; however, significant inhibition was observed in the VEGF-C siRNA treated group. In addition, the cell cycle arrest and apoptosis induced by cisplatin was enhanced by VEGF-C inhibition. Overexpression of maspin was able to improve the sensitivity of BIU87-CisR cells to cisplatin. In conclusion, the resistance of bladder cancer cells to cisplatin may be induced by upregulation of VEGF-C, and inhibition of VEGF-C reverses resistance by elevating maspin expression levels.

Maspin: molecular mechanisms and therapeutic implications

Maspin, a non-inhibitory member of the serine protease inhibitor superfamily, has been characterized as a tumor suppressor gene in multiple cancer types. Among the established anti-tumor effects of Maspin are the inhibition of cancer cell invasion, attachment to extracellular matrices, increased sensitivity to apoptosis, and inhibition of angiogenesis. However, while significant experimental data support the role of Maspin as a tumor suppressor, clinical data regarding the prognostic implications of Maspin expression have led to conflicting results. This highlights the need for a better understanding of the context dependencies of Maspin in normal biology and how these are perturbed in the context of cancer. In this review, we outline the regulation and roles of Maspin in normal and developmental biology while discussing novel evidence and emerging theories related to its functions in cancer. We provide insight into the immense therapeutic potential of Maspin and the challenges related to its successful clinical translation.

An emerging role for the nuclear localization of maspin in the suppression of tumor progression and metastasis

Maspin, a member of the serpin family of serine protease inhibitors, was originally identified as a tumor suppressor that is expressed in normal mammary epithelial cells but is reduced or absent in breast carcinomas. Early enthusiasm for maspin as a biomarker for disease progression has been tempered by clinical data that associates maspin with favourable outcomes in some studies and poor prognosis in others. Here, we review all of the published clinical studies for maspin in breast and ovarian cancers and propose that the apparent discordance between clinical reports is a consequence of differential cellular distribution of maspin. Indeed, it was thought that an extracellular pool of maspin possessed tumor suppressor activity, acting by inhibiting migration and increasing cell adhesion. Recent evidence from our group and others indicates, however, that the nuclear localization of maspin in cancer cells is necessary for its tumor suppressor activity. We provide additional data here to demonstrate that nuclear-localized maspin binds to chromatin and is required to effectively prevent cells from metastasizing. Our knowledge of other serpins that localize to the nucleus should help to inform future studies of nuclear maspin. Elucidation of the molecular mechanisms regulating the localization and activities of maspin should pave the way for the development of improved diagnostics and therapies for cancer.

Clinicopathological correlates and prognostic significance of maspin expression in 450 patients after potentially curative resection of node-positive colonic cancer

AIMS

The tumour suppressor maspin has been investigated for its association with conventional histopathological features in colorectal cancer and for its potential as an independent predictor of survival and response to adjuvant chemotherapy. The aim of this study was to examine associations between maspin expression, other histopathology and survival in a large consecutive series of patients after potentially curative resection of node-positive colonic adenocarcinoma.

METHODS AND RESULTS

Nuclear and cytoplasmic maspin expression in both superficial and deep parts of the tumour were assessed retrospectively by tissue microarray and immunohistochemistry in specimens from 450 patients whose other histopathology had been recorded in a prospective hospital registry of large bowel cancer resections from 1971 to 2001 with a minimum follow-up of 5 years. Among 13 clinicopathological features examined, the only associations that persisted across all four maspin assessments were stronger expression in right- than in left-sided tumours (P=0.001-0.011) and stronger expression in high-grade tumours (P<0.001-0.007). There was no significant association between intensity of maspin expression and overall survival.

CONCLUSIONS

In this large and thoroughly documented series of patients with clinicopathological stage C colonic tumour, maspin expression was correlated with few other conventional histopathology variables and was not a significant prognostic factor.

BRCA1 16 years later: risk-associated BRCA1 mutations and their functional implications

Mutations in the tumor suppressor breast cancer susceptibility gene 1 (BRCA1), an important player in the DNA damage response, apoptosis, cell cycle regulation and transcription, confer a significantly elevated lifetime risk for breast and ovarian cancer. Although the loss of wild-type BRCA1 function is an important mechanism by which mutations confer increased cancer risk, multiple studies suggest mutant BRCA1 proteins may confer functions independent of the loss of wild-type BRCA1 through dominant negative inhibition of remaining wild-type BRCA1, or through novel interactions and pathways. These functions impact various cellular processes and have the potential to significantly influence cancer initiation and progression. In this review, we discuss the functional classifications of risk-associated BRCA1 mutations and their molecular, cellular and clinical impact for mutation carriers.

Shift from cytoplasmic to nuclear maspin expression correlates with shorter overall survival in node-negative colorectal cancer

Maspin has been characterized as a potent tumor suppressor in many in vitro and in vivo studies. In contrast, in stage III colon cancer, an association with shorter overall survival as well as sensitivity to chemotherapy was found for cases with nuclear maspin expression. Because 20% of node-negative colorectal cancer cases show a fatal clinical course, we hypothesized that immunohistochemical maspin expression could be of help to identify higher-risk cases. Therefore, we analyzed survival in a study employing 156 cases of stage I/II colorectal cases. Immunohistochemical cytoplasmic and/or nuclear maspin expression was found in 72% and 48% of the cases, respectively. Significant correlations between cytoplasmic expression and high tumor grade (P < .01) and between nuclear expression and tumor budding (P < .001) were shown. No differences concerning overall survival and immunohistochemical maspin expression were found when the complete collective was analyzed. However, evaluation of the pT3 cases revealed a highly significant worse mean overall survival of cases with a combination of nuclear expression and cytoplasmic loss of maspin compared to cases with the opposite expression pattern nuclear loss and cytoplasmic expression (mean overall survival 40 versus 63 months, respectively; P < .001). The other possible combinations (complete positive and complete negative) showed intermediate mean overall survival times with 54 and 49 months, respectively. Our findings suggest a compartment-dependent function of maspin in colorectal cancer, which can be useful in identifying stage II cases with a higher risk for fatal outcome with a possible benefit from adjuvant chemotherapy.

Mammaglobin and maspin transcripts in blood may reflect disease progression and the effect of therapy in breast cancer

Detection of residual tumor cells in the circulation can provide prognostic as well as therapeutic information and help in identifying patients at high risk for developing metastases. Maspin and mammaglobin are two molecules that are specifically associated with breast cancer. We looked for mammaglobin and maspin transcripts in the peripheral blood of patients with breast cancer and evaluated their utility as a marker of the response to therapy. Maspin and mammaglobin transcripts were analyzed in 85 breast-cancer patients by nested RT-PCR, prior to and after treatment. Before therapy, 10 patients were found positive for mammaglobin and 20 patients were positive for maspin. In four patients, both transcripts were detected. Immediately following treatment, only one patient was still positive for mammaglobin while maspin transcripts persisted in three patients. Disease progression was observed mainly in patients in whom maspin transcripts were not detectable. Molecular detection of circulating tumor cells during therapy based on analysis for mammaglobin and maspin transcripts is an easy and practical method that can be applied to follow-up patients. We suggest that detection of mammaglobin mRNA is useful to determine the effect of therapy while maspin transcripts may indicate more aggressive disease.

BRCA1 185delAG mutant protein, BRAt, up-regulates maspin in ovarian epithelial cells

OBJECTIVE

Aggressive clinical course and difficult detection of ovarian cancer are major challenges to improving patient survival and necessitate avid investigation into more effective therapeutic approaches. Understanding early molecular and pathological changes in high risk patients, such as BRCA1 mutation carriers, can provide candidates for molecular profiling and novel targets for effective therapies.

METHODS

Using a culture model system for normal human ovarian surface epithelial cells with and without the BRCA1 185delAG frameshift mutation for the truncated protein product, BRAt, we investigated the role of BRAt in enhanced chemosensitivity. We used MTS, Western immunoblot, semi-quantitative RT-PCR, luciferase reporter and siRNA assays, to identify novel downstream targets of BRAt that promote apoptosis following chemotherapeutic treatment.

RESULTS

We identified maspin as a novel downstream target of BRAt. BRAt increases maspin expression with preferential nuclear localization of maspin. Further, Brat-mediated maspin expression is transcriptionally regulated through an AP1 site within the (-520) to (-297) region of the promoter. Lastly, BRAt, enhances chemosensitivity in normal ovarian surface epithelial cells through c-Jun by a mechanism that may involve maspin.

CONCLUSIONS

BRAt-mediated enhanced chemosensitivity correlates clinically with enhanced chemotherapeutic response in BRCA1 mutation carriers. BRAt-mediated maspin expression also correlates with improved prognostic outlook for ovarian tumors with high levels of nuclear maspin. Consequently, understanding early genotypic and phenotypic changes in the context of high risk disease may provide a better understanding of the mechanism of mutation-associated ovarian cancer and provide new targets for therapeutic intervention.

MASPIN's prognostic role in patients with advanced head and neck carcinoma treated with primary chemotherapy (carboplatin plus vinorelbine) and radiotherapy: preliminary evidence

CONCLUSIONS

Our very preliminary results support the hypothesis that MASPIN expression in primary head and neck squamous cell carcinoma (HNSCC) may be a valuable parameter for predicting patients' responses to a treatment based on carboplatin plus vinorelbine combined with radiotherapy.

OBJECTIVES

The roles of induction chemotherapy and combined chemoradiotherapy in the treatment of locally advanced unresectable HNSCCs have evolved rapidly. MASPIN has a unique tumour-suppressing activity. Experimental evidence has shown that MASPIN suppresses tumour growth, angiogenesis, invasion and metastasis. We investigated the potential prognostic roles of MASPIN and p53 in a series of HNSCCs treated with carboplatin plus vinorelbine combined with radiotherapy.

PATIENTS AND METHODS

Nineteen consecutive stage III or IV HNSCC patients were recruited. The treatment plan consisted of the administration of carboplatin on day 1 and vinorelbine on days 1 and 8. Four weeks later, carboplatin was administered concomitantly with radiation therapy. Expression of MASPIN and p53 was determined immunohistochemically in HNSCC diagnostic biopsies.

RESULTS

A significant inverse relation was found between MASPIN expression and cN staging (p = 0.003). From a prognostic viewpoint, MASPIN expression was directly correlated with chemoradiotherapy response (p = 0.041). Moreover, the log-rank test showed a significant relationship between higher MASPIN expression and longer disease-free survival (p = 0.03), overall survival (p = 0.006) and disease-specific survival (p = 0.007).

Maspin overexpression correlates with increased expression of vascular endothelial growth factors A, C, and D in human ovarian carcinoma

The vascular endothelial growth factor (VEGF) family, including VEGFA, VEGFC, and VEGFD, plays an essential role in the angiogenesis of both pathologic and nonpathologic conditions. Maspin belongs to the serpin superfamily and has been identified as a tumor suppressor because it inhibits motility, invasion, and angiogenesis. Few studies have compared maspin with VEGF in ovarian carcinoma. Therefore, we investigated the expression and correlation of maspin, VEGFA, VEGFC, and VEGFD with the tumorigenesis of the ovary and clinicopathologic variables. Using immunohistochemistry, we examined maspin, VEGFA, VEGFC, and VEGFD expression in 60 ovarian carcinoma tissues (35 serous papillary carcinomas, 18 endometrioid carcinomas, and 7 primary ovarian mucinous carcinomas). Staining of cells was scored as +2 if more than 50% of the cells were positive, as +1 if less than 50% of the cells were positive, and as negative if none of the cells stained positive. Overexpression of maspin, VEGFC, and VEGFD was significantly associated with high tumor grade (P<.001, P=.004, P<.001, respectively), clinical stage (P=.002, .01, and .001, respectively), the presence of ascites (P<.001, P=.03, and P=.001, respectively), and the presence of metastatic lymph nodes (P=.002, P<.001, and P<.001, respectively). Maspin was correlated with VEGFA (P=.01), VEGFC (P<.001), and VEGFD (P<.001). The VEGFA score was positively correlated with high tumor grade (P=.04), lymphovascular space invasion (LVSI) (P<.001), International Federation of Gynecology and Obstetrics (FIGO) stage (P=.009), maspin, VEGFC (P=.003), and VEGFD (P=.003), but it was not correlated with the presence of ascites and metastatic lymph nodes. Maspin, VEGFC, and VEGFD are expressed in ovarian tumors with a poor prognostic parameters, and seem to play a role in ovarian cancer angiogenesis, progression, and lymph node metastases. Our results indicate that in contrast to most other carcinomas, maspin expression is directly associated with the biological aggressiveness of ovarian carcinoma. These results may offer new insights regarding the role of maspin in ovarian cancer and might also affect the diagnosis and treatment strategies.