Prognostic significance of bcl-2 expression in leiomyosarcoma of the uterus

Potential Markers to Differentiate Uterine Leiomyosarcomas from Leiomyomas

Uterine leiomyomas (ULM) are the most common benign tumors of the female genitalia, while uterine leiomyosarcomas (ULMS) are rare. The sarcoma is diffuse growth, prone to hematogenous metastasis, and has a poor prognosis. Due to their similar clinical symptoms and morphological features, it is sometimes difficult to distinguish them, and the final diagnosis depends on histological diagnosis. Misdiagnosis of ULM as ULMS will lead to more invasive and extensive surgery when it is not needed, while misdiagnosis of ULMS as ULM may lead to delayed treatment and poor prognosis. This review searched and studied the published articles on ULM and ULMS, and summarized the potential markers for the differential diagnosis of ULMS. These markers will facilitate differential diagnosis and personalized treatment, providing timely diagnosis and potentially better prognosis for patients.

Diagnostic and prognostic value of Bcl-2 in uterine leiomyosarcoma

BACKGROUND

Uterine leiomyosarcoma (uLMS) may show loss of expression of B-cell lymphoma-2 (Bcl-2) protein. It has been suggested that Bcl-2 loss may both be a diagnostic marker and an unfavorable prognostic marker in uLMS.

OBJECTIVE

To define the diagnostic and prognostic value of Bcl-2 loss in uLMS through a systematic review and meta-analysis.

METHODS

Electronic databases were searched from their inception to May 2020 for all studies assessing the diagnostic and prognostic value of Bcl-2 loss of immunohistochemical expression in uLMS. Data were extracted to calculate odds ratio (OR) for the association of Bcl-2 with uLMS vs leiomyoma variants and smooth-muscle tumors of uncertain malignant potential (STUMP), and hazard ratio (HR) for overall survival; a p value < 0.05 was considered significant.

RESULTS

Eight studies with 388 patients were included. Loss of Bcl-2 expression in uLMS was not significantly associated with a diagnosis of uLMS vs leiomyoma variants and STUMP (OR = 2.981; p = 0.48). Bcl-2 loss was significantly associated with shorter overall survival in uLMS (HR = 3.722; p = 0.006). High statistical heterogeneity was observed in both analyses.

CONCLUSION

Loss of Bcl-2 expression appears as a significant prognostic but not diagnostic marker in uLMS. The high heterogeneity observed highlights the need for further research and larger studies.

Ki67 as a prognostic marker in uterine leiomyosarcoma: A quantitative systematic review

Ki67 labeling index (LI) has been proposed as a prognostic factor in uterine leiomyosarcoma (uLMS), although the evidence in this field is still unclear. We aimed to assess the prognostic value of ki67 LI in uLMS. A systematic review was performed by searching electronic databases from their inception to August 2020 for all studies assessing the prognostic value of ki67 LI in uLMS. Ki67 LI was assessed to the nearest 10% to define the most prognostically accurate threshold. Cox regression survival analysis with calculation of hazard ratio (HR) of death was performed; a p-value < 0.05 was considered significant. Ten studies were included in the qualitative review, out of which 6 were suitable for quantitative review. The absolute risk of death was 0.29 for a ki67 LI < 10%, remained stable at 0.49 in the 10%-39% LI range and increased to 0.65 for a LI ≥ 40%. On univariate analysis, both 10% and 40% thresholds were significantly associated with the hazard of death, with HRs of 3.349 (p = 0.007) and 3.172 (p = 0.001), respectively. On multivariate analysis, only the 10% threshold was significantly associated with the hazard of death (HR = 2.712; p = 0.028). In conclusion, a Ki67 LI ≥ 10% is a significant prognostic factor in uLMS.

The Usefulness of Immunohistochemistry in the Differential Diagnosis of Lesions Originating from the Myometrium

Uterine leiomyomas (LMs), currently the most common gynecological complaint around the world, are a serious medical, social and economic problem. Accurate diagnosis is the necessary prerequisite of the diagnostic-therapeutic process. Statistically, mistakes may occur more often in case of disease entities with high prevalence rates. Histopathology, based on increasingly advanced immunohistochemistry methods, is routinely used in the diagnosis of neoplastic diseases. Markers of the highest sensitivity and specificity profiles are used in the process. As far as LMs are concerned, the crux of the matter is to identify patients with seemingly benign lesions which turn out to be suspicious (e.g., atypical LM) or malignant (e.g., leiomyosarcoma (LMS)), which is not uncommon. In this study, we present the current state of knowledge about the use of immunohistochemical markers in the differential diagnosis of LM, atypical LM, smooth muscle tumors of uncertain malignant potential (STUMP), and LMS, as well as their clinical predictive value.

DNA fragmentation factors 40 and 45 (DFF40/DFF45) and B-cell lymphoma 2 (Bcl-2) protein are underexpressed in uterine leiomyosarcomas and may predict survival

OBJECTIVES

DNA fragmentation factors 40 and 45 (DFF40 and DFF45) are responsible for final DNA-laddering during apoptosis, whereas Bcl-2 (B-cell lymphoma 2) is an apoptosis inhibitor. Our aim was to investigate the expression of DFF40, DFF45, and Bcl-2 in uterine leiomyosarcomas (uLMS), leiomyomas (uLM), and the normal myometrium. Furthermore, the correlation between DFF40, DFF45, and Bcl-2 expression and clinicopathological parameters in leiomyosarcomas was assessed. Their prognostic value in disease-free survival (DFS) and overall survival (OS) was also calculated.

MATERIALS AND METHODS

This study included 53 cases of uLMS from patients matched for age and menopausal status with 53 cases of uLM and 53 controls of normal myometrium (uM). Case samples of uterine myometrium from leiomyosarcomas (uLMS-M) and leiomyomas (uLM-M) were also studied. Immunohistochemical scoring was undertaken for DFF40, DFF45, and Bcl-2.

RESULTS

DFF40, DFF45, and Bcl-2 were significantly underexpressed in uLMS compared with uLMS-M and uM. In uLMS samples, no correlation between the analyzed proteins was observed. Negative DFF40 and Bcl-2, but not DFF45, staining was a predictor of poorer DFS and OS in women with uLMS. uLM showed DFF40 and Bcl-2 overexpression compared with uM and uLM-M, with a significant positive correlation between DFF40 and DFF45. No differences in DFF40, DFF45, and Bcl-2 expression were observed between the uLMS-M, uLM-M, and uM samples, with a significant positive correlation between DFF40 and DFF45 expression.

CONCLUSION

DFF40, DFF45, and Bcl-2 are significantly underexpressed in uLMS, but only a lack of DFF40 and Bcl-2 negatively influences DFS and OS. Disruption of DFF40 and DFF45 expression was observed in uLMS, but not in uLM or control and case myometrium; this may play a role in tumor pathogenesis.

Potential role of BCL2 in the recurrence of uterine smooth muscle tumors of uncertain malignant potential

Uterine smooth muscle tumors are the most common female genital tract neoplasms. While leiomyosarcoma has been studied at length, smooth muscle tumors of uncertain malignant potential (STUMPs) still have ambiguous and unresolved issues, with a risk of relapse and evolution largely undefined. We performed an array comparative genomic hybridization analysis on a primitive STUMP and its local recurrence, histologically diagnosed as undifferentiated sarcoma. To the best of our knowledge, our report is the first genomic study on primitive STUMPs and the different relapsed tumors. The results showed few copy number alterations shared between both samples and the high heterogeneity in the STUMP was apparently lost in the sarcoma. Surprisingly the STUMP presented an amplification of the BCL2 gene, not observed in the relapsed tumor. Additionally, fluorescence in situ hybridization and immunohistochemical staining were performed to confirm BCL2 amplification and expression in these samples and in two other cases of primitive STUMPs and their corresponding relapsed tumors. The presence of BCL2 in multiple copies and expression in the two primitive STUMPs and two relapsed tumors was confirmed. The marked amplification of the BCL2 gene present in the primitive STUMP and the multiple copies also observed in other cases, suggest its potential role as a marker of STUMP malignant potential and recurrence.

Bcl-2 Receptor Expression in Patients With Uterine Smooth Muscle Tumors: An Immunohistochemical Analysis Comparing Leiomyoma, Uterine Smooth Muscle Tumor of Uncertain Malignant Potential, and Leiomyosarcoma

OBJECTIVE

Bcl-2 protein is an apoptosis-inhibiting gene product that prevents the normal course of apoptotic cell death in a variety of cells. Additionally, bcl-2 can promote cell replication by reducing the requirement for growth factors. This protein seems, therefore, to play an important role in the growth of tumors. Our aim was to investigate the different expression of bcl-2 in uterine leiomyomas, smooth muscle tumors of uncertain malignant potential (STUMP), and leiomyosarcomas (LMS). Furthermore, the correlation between bcl-2 expression and various clinicopathologic parameters in leiomyosarcomas was assessed to evaluate its prognostic value.

METHODS

This study included 26 cases of leiomyoma, 22 cases of STUMP, and 21 cases of LMS of the uterus. Bcl-2 expression was investigated by immunohistochemistry from paraffin-embedded tissue. The immunohistochemical findings were compared and correlated with different clinicopathologic parameters. Clinical information, including follow-up data, was obtained from the database of the Department of Gynecology and Obstetrics.

RESULTS

Bcl-2 was present in 12 of 21 LMS, eight of 22 STUMP, and 20 of 25 leiomyomas. Significant differences regarding the frequency of bcl-2 expression and the staining intensity were observed between LMS and leiomyoma as well as between STUMP and leiomyoma (P <.05) but not between LMS and STUMP (P >.05). Regarding the outcome of uterine LMS, patients with bcl-2 positive tumors showed less vascular space involvement and longer overall survival (P <.05).

CONCLUSION

Bcl-2 was expressed more frequently and more strongly in leiomyomas compared with LMS and STUMP. Regarding the outcome of uterine LMS, patients with bcl-2-positive tumors showed less vascular space involvement and longer overall survival. The stronger bcl-2 expression in benign leiomyomas and the better clinical outcome of bcl-2-positive LMS indicate that this protein seems to act as a good prognostic factor. Further studies including larger numbers of patients are necessary to establish bcl-2 as a routine marker for improved prognosis in malignant uterine smooth muscle tumors.

Estrogen Metabolite 2-Methoxyestradiol Induces Apoptosis and Inhibits Cell Proliferation and Collagen Production in Rat and Human Leiomyoma Cells: A Potential Medicinal Treatment for Uterine Fibroids

OBJECTIVE

The current study sought to investigate the effect of the estrogen metabolite 2-methoxyestradiol (2-MeOHE(2)) on apoptosis, cell proliferation, and collagen synthesis in human and rat leiomyoma cells.

METHODS

[(3)H] thymidine and [(3)H] proline incorporation studies were conducted. The expression of vascular endothelial growth factor (VEGF), cyclin D1, Bcl-2, and Bax were evaluated by Western blot. Flow cytometry analysis was used to study the effect of 2-MeOHE(2) on apoptosis and the cell cycle.

RESULTS

Compared with untreated controls, treatment of rat leiomyoma (ELT3) cells with 2-MeOHE(2) (0.1, 1, 2, 5, or 10 muM) reduced cell proliferation by 17%, 52%, 61%, 73%, and 79%, respectively (P <.05). Similarly, in human uterine leiomyoma cell line (huLM) cells, proliferation was reduced by 4%, 18%, 37%, 41%, and 51%, respectively. 2-MeOHE(2) also caused a concentration-dependent inhibition of collagen synthesis by 4%, 16%, 23%, 51%, and 70%, respectively, in huLM cells (P <.05). Cell cycle analysis indicated that 2-MeOHE(2) treatment (1 to 5 muM) in huLM cells resulted in G(2)/M cell cycle arrest and a 45% increase in apoptosis compared with untreated control (P <.05). Western immunoblotting analysis indicated that 2-MeOHE(2) induces a concentration-dependent reduction in the expression of cyclin D1, Bcl-2, and VEGF proteins in both rat and human leiomyoma cell lines.

CONCLUSIONS

This study provides the first evidence that 2-MeOHE(2) is a potent antiproliferative/apoptotic and collagen synthesis inhibiting agent in human and rat leiomyoma cells. To the best of our knowledge, this is the first report showing the potential use of 2-methoxyestradiol as a nonsurgical alternative therapy for uterine leiomyomas.

Preparation, characterization, and evaluation of antitumor effect of Brucea javanica oil cationic nanoemulsions

The purpose of this study was to prepare Brucea javanica oil cationic nanoemulsions (BJO-CN) with BJO as drug as well as oil phase and chitosan as cationic inducer, to explore the practical suitability of using cationic nanoemulsions for oral delivery of mixed oil, and to test its bioavailability and antitumor effect. BJO-CN was prepared by chitosan solution stirring method and then characterized physicochemically. The obtained BJO-CN had a spherical morphology with a positive zeta potential of 18.9 mV and an average particle size of 42.36 nm, showing high colloidal stability. The drug loading of BJO-CN was 91.83 mg·mL⁻¹, determined by high-performance liquid chromatography with precolumn derivatization. Pharmacokinetic studies revealed that, compared with BJO emulsion (BJO-E) (the dosage of BJO-CN and BJO-E was equal to 505 mg·kg⁻¹, calculated by oleic acid), BJO-CN exhibited a significant increase in the area under the plasma drug concentration–time curve over the period of 24 hours and relative bioavailability was 1.6-fold. Furthermore, the antitumor effect of BJO-CN in the orthotopic mouse model of lung cancer was evaluated by recording the median survival time and the weight of lung tissue with tumor, hematoxylin and eosin staining, and immunohistochemical technique. Results of anticancer experiments illustrated that, even though the administrated dosage in the BJO-CN group was half of that in the BJO-E group, BJO-CN exhibited similar antitumor effect to BJO-E. Moreover, BJO-CN had good synergistic effect in combination therapy with vinorelbine. These results suggested that cationic nanoemulsions are an effective and promising delivery system to enhance the oral bioavailability and anticancer effect of BJO.

Inhibition of Bcl-2 family members sensitises soft tissue leiomyosarcomas to chemotherapy

Background:

Leiomyosarcoma is an aggressive soft tissue sarcoma with a 5-year survival rate of 15 to 60%. Treatment options for inoperable or metastatic patients are limited owing to frequent resistance of tumours to chemotherapy and radiation. In this study, we hypothesised that antiapoptotic Bcl-2 family proteins might contribute to leiomyosarcoma chemoresistance and therefore inhibition of Bcl-2 family proteins might sensitise leiomyosarcomas to conventional chemotherapy.

Methods:

Expression of the Bcl-2 family proteins Bcl-xL, Bcl-w and Bcl-2 was investigated using immunohistochemistry on a tissue microarray containing 43 leiomyosarcomas. Furthermore, we investigated whether ABT-737, a potent BH3 mimetic, sensitises leiomyosarcoma cells to doxorubicin treatment in vitro.

Results:

Seventy-seven per cent, 84% and 42% of leiomyosarcomas demonstrated high expression of Bcl-2, Bcl-xL and Bcl-w, respectively. Single-agent treatment with ABT-737 resulted in a minor reduction of cell viability. However, combination treatment of ABT-737 and doxorubicin revealed synergism in all four cell lines, by inducing apoptosis.

Conclusions:

In conclusion, Bcl-2 family proteins contribute to soft tissue leiomyosarcoma chemoresistance. Antiapoptotic proteins are highly expressed in leiomyosarcoma of soft tissue, and inhibition of these proteins using a BH3 mimetic increases leiomyosarcoma sensitivity to doxorubicin.

Value of counting positive PHH3 cells in the diagnosis of uterine smooth muscle tumors

The diagnosis of uterine smooth muscle tumors including leiomyosarcomas (LMS), smooth muscle tumors of uncertain malignant potential (STUMP), bizarre (atypical) leiomyoma (BLM), mitotically active leiomyoma (MAL) and leiomyoma (LM) depends on a combination of microscopic features, such as mitoses, cytologic atypia, and coagulative tumor cell necrosis. However, a small number of these tumors still pose difficult diagnostic challenges. The assessment of accurate mitotic figures (MF) is one of the major parameters in the proper classification of uterine smooth muscle tumors. This assessment can be hampered by the presence of increased number of apoptotic bodies or pyknotic nuclei, which frequently mimic mitoses. Phospho-histone H3 (PHH3) is a recently described immunomarker specific for cells undergoing mitoses. In our study, we collected 132 cases of uterine smooth muscle tumors, including 26 LMSs, 16 STUMPs, 30 BLMs, 30 MALs and 30 LMs. We used mitosis specific marker PHH3 to count mitotic indexes (MI) of uterine smooth muscle tumors and compared with the mitotic indexes of hematoxylin and eosin (H&E). There is a positive correlation with the number of mitotic figures in H&E-stained sections and PHH3-stained sections (r=0.944, P<0.05). The ratio of PHH3-MI to H&E-MI has no statistically significant difference in each group except for LMs (P>0.05). The counting value of PHH3 in LMSs have significantly higher than STUMPs, BLMs, MALs and LMs (P<0.001) and the counting value of PHH3 is 1.5±0.5 times of the number of mitotic indexes in H&E. To conclude, our results show that counting PHH3 is a useful index in the diagnosis of uterine smooth muscle tumors and it can provide a more accurate index instead of the time-honored mitotic figure counts at a certain ratio.

The expression and characterization of endoglin in uterine leiomyosarcoma

Endoglin (CD105), an accessory receptor of transforming growth factor-β, is expressed in vascular endothelial cells. Recently, it was reported that endoglin expression was significantly associated with poorer survival in several cancers. In this study, we evaluated the role of endoglin in uterine leiomyosarcoma. We examined the expression of endoglin in 22 uterine leiomyosarcomas and the association between their expression and the outcome. Additionally, to evaluate the function of endoglin, we used SKN cells, a human uterine leiomyosarcoma cell line. We generated SKN cells stably transfected with plasmids encompassing shRNA targeting endoglin (shEng cells), and compared the ability of proliferation, migration, and invasion to control shRNA-transfected cells (shCon cells). We compared the level of VEGF and matrix metalloproteinases (MMP) in culture supernatants of shEndoglin and shControl cells. Nine patients were endoglin-positive and 13 patients were -negative. The endoglin-positive group had a significantly poorer overall survival and progression-free survival than the endoglin-negative group. In an in vitro study, there was no difference in cell proliferation between shEng and shCon cells. On the other hand, shEng cells showed a lower ability for migration and invasion than shControl cells. The activity of MMP-9 and VEGF level in the supernatant from shEng cells were lower than in shCon cells. In uterine leiomyosarcoma, endoglin expression was associated with a poor prognosis. It was suggested that endoglin up-regulated invasion and VEGF secretion. The investigation of endoglin may lead to a new strategy in uterine leiomyosarcoma therapy.

Targeting the p53 Pathway in Ewing Sarcoma

The p53 tumour suppressor plays a pivotal role in the prevention of oncogenic transformation. Cancers frequently evade the potent antitumour surveillance mechanisms of p53 through mutation of the TP53 gene, with approximately 50% of all human malignancies expressing dysfunctional, mutated p53 proteins. Interestingly, genetic lesions in the TP53 gene are only observed in 10% of Ewing Sarcomas, with the majority of these sarcomas expressing a functional wild-type p53. In addition, the p53 downstream signaling pathways and DNA-damage cell cycle checkpoints remain functionally intact in these sarcomas. This paper summarizes recent insights into the functional capabilities and regulation of p53 in Ewing Sarcoma, with a particular focus on the cross-talk between p53 and the EWS-FLI1 gene rearrangement frequently associated with this disease. The development of several activators of p53 is discussed, with recent evidence demonstrating the potential of small molecule p53 activators as a promising systemic therapeutic approach for the treatment of Ewing Sarcomas with wild-type p53.

A new scoring system using multiple immunohistochemical markers for diagnosis of uterine smooth muscle tumors

The diagnosis of uterine smooth muscle neoplasms by light microscopy is difficult. Multiple classification schemes have been proposed based on mitotic rate, nuclear atypia, and the presence or absence of necrosis. None of these classification systems has been entirely successful. This study was undertaken to evaluate the use of selected immunohistochemical and histochemical markers in differentiating these tumors, in addition to accepted morphologic criteria. Ten cases of each of the following: leiomyosarcomas (LMS), atypical leiomyomas (AL), cellular leiomyomas (CL) and usual leiomyomas (UL), were classically evaluated for histological diagnosis and were stained for Ki-67 (MIB-1), bcl-2 and p53 using monoclonal antibodies and the avidin-biotin peroxidase method, and argyrophilic nucleolar organizer region (AgNORs). The number of stained cells was counted in the most positively stained region in a 4 mm² square cover glass mounted on each slide. The mean value was calculated for each group of tumors. The data for Ki-67 (MIB-1), bcl-2, p53 and AgNOR staining respectively, were significantly higher in LMS by comparison to UL, CL or AL. Because many singular cases had superimposed data being difficult to diagnose, a new scoring system for pathological evaluation was created. The results obtained by this scoring system suggest that immunohistochemical markers Ki-67 (MIB-1), bcl-2, p53 together with the AgNOR staining could be useful, by the scoring system, as an adjunct to the current accepted morphologic criteria in differentiating smooth muscle tumors of the uterus.

Apoptotic and cell cycle regulatory markers in uterine leiomyosarcoma

OBJECTIVES

The primary aim of this study was to investigate the expression of apoptotic and cell cycle regulators p53, p21, p27, bax, and bcl-2 in uterine leiomyosarcoma in order to identify molecular pathways that possibly could be important in the development of leiomyosarcoma. A secondary aim was to examine if the apoptotic and cell cycle regulatory protein expression profile of uterine leiomyosarcoma is potentially useful for clinical prognostic purposes.

METHODS

A tissue microarray representing 36 uterine leiomyosarcomas and 19 uterine leiomyomas was created with 3 representative cores from each tumor. Immunohistochemical staining was performed for bcl-2, bax, p21, p27, and p53 using standard techniques. Staining was scored 0-12 for each marker, 0-3 being negative and 4-12 positive. Outcome analyses were performed only for leiomyosarcomas. First recurrence was determined from the time of initial diagnosis. Survival was determined from the time of initial diagnosis to last follow-up.

RESULTS

Associations were found between disease type (leiomyosarcoma vs. leiomyoma) and the positivity status of p21 (43% vs. 0%, P < 0.001), p53 (54% vs. 0%, P < 0.001), and bax (34% vs. 94%, P < 0.001). bcl-2-positive leiomyosarcoma was associated with a longer time to recurrence (P = 0.02) in a univariate analysis. In a multivariate analysis, tumor stage was the only independent significant prognostic factor (P = 0.002).

CONCLUSION

The significant differential expression of apoptotic and cell cycle regulatory proteins in uterine leiomyosarcoma as compared to benign smooth muscle tumors suggests that pathways involving these proteins may be important in the development of malignant disease and, therefore, could be potential targets for molecular therapies.

Analysis of Allelic Loss as an Adjuvant Tool in Evaluation of Malignancy in Uterine Smooth Muscle Tumors

Uterine smooth muscle tumors of uncertain malignant potential (STUMPs) are difficult both from the diagnostic and patient management standpoint because they cannot be classified as benign or malignant by conventional histologic criteria. This study's aim was to determine the diagnostic utility of allelic imbalance (AI) analysis in uterine smooth muscle tumors. Using microdissection and genotyping, we tested 5 leiomyomas, 6 STUMPs, and 10 leiomyosarcomas with follow-up for AI across a panel of seven tumor suppressor genes (p16, p21, p53, VHL, XRCC3, RB, and NM-23). None of the 6 patients with STUMP experienced recurrent disease, whereas 8 of the 10 patients diagnosed with leiomyosarcoma died of disease at follow-up. The mean frequency of allelic loss (FAL) for leiomyomas (18%) was not significantly different from that of STUMPs (21%) (P = 1), whereas leiomyosarcomas displayed a significantly higher FAL (52%) than both leiomyomas (P = 0.001) and STUMPs (P = 0.002). Loss of NM-23, a reported tumor metastasis suppressor gene, was found only in leiomyosarcomas (5 of 9, or 56%), and 4 of 5 (80%) of these were the only cases that demonstrated distant metastases (P = 0.04). Additionally, an FAL of >50% correlated with both NM-23 loss (P = 0.008) and distant metastatic disease (P = 0.04). In conclusion, leiomyomas and STUMPs displayed similar mean FALs and all were clinically benign, whereas uterine leiomyosarcomas had significantly higher frequencies of allelic loss than both leiomyomas and STUMPs. Molecular profiling may thus provide a valuable tool in assessment of malignancy in uterine smooth muscle tumors. Additionally, NM-23 is a promising candidate gene for determination of metastatic potential in these tumors.

Estrogen and Progesterone Receptor Expression in Uterine and Extrauterine Leiomyosarcomas

The authors have noted anecdotal cases of extrauterine leiomyosarcomas (LMS) with estrogen receptor (ER) and progester-one receptor (PR) immunoreactivity. However, there are few studies that have compared ER and PR immunoexpression in LMS of uterine and extrauterine origin. The authors obtained a representative formalin-fixed, paraffin-embedded tissue block from cases of uterine LMS (n = 15) and extrauterine LMS (n = 16) from the archives of the Cleveland Clinic Foundation and performed immunohistochemical staining for ER and PR. Staining was evaluated by 2 observers in a semiquantitative manner using the following scale: 0, no nuclear staining; 1+, 1 to 25% of nuclei stained; 2+, 26 to 50% of nuclei stained; 3+, 51 to 75% of nuclei stained; 4+, 76 to 100% of nuclei stained. The majority of uterine LMS stained for ER (13 of 15, 87%), PR (12 of 15, 80%), or both ER and PR (12 of 15, 80%), with most cases showing 3+ or 4+ positive staining. For the extrauterine LMS cases, staining for ER was seen in 4 of 16 cases (25%), staining for PR was observed in 2 of 16 cases (13%), and staining for both ER and PR was seen in 2 of 16 cases (13%). One extrauterine LMS showed 4+ coexpression of ER and PR, but the remaining extrauterine cases showed only 1+ ER and/or PR immunoreactivity. These data suggest that most uterine LMS coexpress ER and PR, and most extrauterine LMS do not stain for these antigens. However, a subset of extrauterine LMS are ER and/or PR immunoreactive. This raises the possibility that hormonal manipulation may be beneficial in the treatment of these therapeutically recalcitrant tumors.

Ki-67 expression in patients with uterine leiomyomas, uterine smooth muscle tumors of uncertain malignant potential (STUMP) and uterine leiomyosarcomas (LMS)

BACKGROUND

The aim of the current study was to evaluate the expression of Ki-67 in uterine smooth muscle tumors, comparing leiomyomas, uterine smooth muscle tumors of uncertain malignant potential (STUMP) and uterine leiomyosarcomas (LMS) and to prove the accuracy of a Ki-67 expression as a useful parameter in the diagnosis of LMS.

METHODS

Ki-67 was assessed using immunohistochemistry from paraffin-embedded tissue in 20 patients with uterine LMS, 22 cases of STUMP and 25 cases of leiomyomas.

RESULTS

Ki-67 was present in 10/20 (50%) LMS, in 0/22 (0%) STUMP and in 2/25 (8%) leiomyomas. Significant differences regarding the frequency of Ki-67 expression were observed between LMS and STUMP (p = 0.0001) as well as between LMS and leiomyomas (p = 0.002), but not between STUMP and leiomyomas (p = 0.491). Likewise, the staining intensity differed significantly between LMS and leiomyomas (p = 0.018) as well as between LMS and STUMP (p = 0.002), but not between STUMP and leiomyomas (p = 0.368).

CONCLUSIONS

Our results demonstrate that the significantly elevated Ki-67 antigen expression in LMS, which correlates well with the rapid growth of these malignant tumors, may be a useful immunohistochemical parameter to distinguish between cases of malignant smooth muscle tumors and those of uncertain or borderline histology.

Expression of matrix metalloproteinases in patients with uterine smooth muscle tumors: an immunohistochemical analysis of MMP-1 and MMP-2 protein expression in leiomyoma, uterine smooth muscle tumor of uncertain malignant potential, and leiomyosarcoma

OBJECTIVE

Matrix metalloproteinases (MMPs) have been suggested to play an important role in tumor invasion and metastasis. We compared the expression of MMP-1 and MMP-2 protein in patients with leiomyoma, uterine smooth muscle tumor of uncertain malignant potential (STUMP), and leiomyosarcoma (LMS).

METHODS

MMP-1 and MMP-2 expression was investigated by immunohistochemistry from paraffin-embedded tissue in 26 patients with leiomyoma, in 24 patients with STUMP, and in 21 patients with LMS.

RESULTS

MMP-1 was expressed in 92% of leiomyomas, in 83% of STUMP, and in 86% of LMS, whereas MMP-2 was expressed in 12% of leiomyomas, in 17% of STUMP, and in 48% of LMS. A statistically significant difference regarding the frequency of MMP-2 expression was observed between LMS and STUMP (P =.025) as well as between LMS and leiomyoma (P =.006), but not between STUMP and leiomyoma (P >.05). Likewise, the staining intensity did significantly differ between LMS and leiomyoma (P =.025), but no statistical significant difference was observed between LMS and STUMP (P >.05) and between STUMP and leiomyoma (P >.05).

CONCLUSION

The stronger MMP-2 expression in patients with LMS compared with STUMP and leiomyoma indicates that this protein might be a marker for tumor invasion or metastasis in patients with uterine LMS. Furthermore, MMP-2 seems to be a useful immunohistochemical parameter to distinguish cases of smooth muscle tumors in which histologic features are ambiguous or borderline. Further studies including larger numbers of patients are necessary to establish MMP-2 as a routine marker for tumor invasion and progression.

Bcl-2 expression and other clinicopathologic parameters in uterine leiomyosarcoma

BACKGROUND

The bcl-2 protein, which is involved in cell-cycle regulation and apoptosis, seems to play an important role in the growth of tumors. Until recently, only one study described the frequent expression of bcl-2 in uterine leiomyosarcomas (LMS) and indicated its important prognostic role. Thus, the aims of the present study were to examine bcl-2 expression in patients with uterine LMS and to determine if the expression of this protein would influence the prognosis. In addition, a possible association between bcl-2 expression and various clinicopathologic parameters was evaluated.

PATIENTS AND METHODS

Bcl-2 expression was investigated using immunohistochemical techniques on paraffin-embedded tissue from 21 patients with uterine LMS. The immunohistochemical findings were correlated with different clinicopathologic parameters (FIGO stage, age, vascular-space involvement and recurrence of disease) of the patients.

RESULTS

Bcl-2 was expressed in 57% (12/21) of uterine LMS: 3/12 (25%) stained weakly positive, 3/12 (25%) stained moderately positive and 6/12 (50%) stained strongly positive. Nine (43%) cases were negative. Evaluation of the correlation between bcl-2 expression and several clinicopathologic parameters identified a significant negative correlation between vascular-space involvement and bcl-2 expression (p=0.04). The relationship between bcl-2 expression and FIGO stage, age and recurrence of disease did not reach statistical significance. A univariate Cox model revealed significantly longer overall survival in women with bcl-2-positive LMS compared with women with bcl-2-negative LMS (p=0.03).

CONCLUSIONS

Significant negative correlation was found between bcl-2 expression and vascular-space involvement and improved survival rates in patients with bcl-2-positive tumors. Though limited by the small number of patients, these data indicate the role of bcl-2 expression in uterine LMS.

Bcl-2 expression in a primary leiomyosarcoma of the ovary: a case report

BACKGROUND

Primary ovarian leiomyosarcoma is an extremely rare malignant smooth-muscle neoplasm with fewer than 30 documented cases worldwide. Immunohistochemically, ovarian leiomyosarcomas are characterized by the expression of alpha-smooth muscle actin (alpha-SMA). Until recently, no report investigated the role of bcl-2 expression in primary ovarian leiomyosarcoma. We report the management and an immunohistochemical analysis of bcl-2 in a patient with primary leiomyosarcoma of the ovary.

CASE REPORT

The patient, a 71-year-old woman, presented with a history of lower abdominal pain and a palpable mass in the lower abdomen. Surgical exploration revealed a large left adnexal mass that had developed from the left ovary and infiltrated one part of the omentum adherent to the left adnexa. Microscopically the left adnexal tumor consisted of spindle cells arranged in smooth-muscle bundles and fascicles. The tumor was characterized by high cellularity and nuclear polymorphism, as well as patchy necrosis and large areas of hemorrhage. Mitotic activity exceeded 5 mitoses per 10 high-power fields with many atypical mitoses. The tumor appeared encapsulated, and the capsule was partially disrupted by tumor cells. Immunohistochemically, the tumor showed a strong staining reaction for muscle actin, alpha-SMA and neuron-specific enolase, and also a weak reaction for vimentin. Strong staining of bcl-2 was detected, with more than 80% of sarcoma cells positive. According to the FIGO staging system for ovarian cancer, the tumor was classified as a primary ovarian leiomyosarcoma stage III C, and the patient was treated with an adjuvant chemotherapy regimen consisting of cisplatin and ifosfamide. Two days after the third cycle of cisplatin/ifosfamid she developed an apoplexy spontaneously and chemotherapy was therefore discontinued. The patient remained without evidence of disease until she died as a result of intercurrent pneumonia 14 months after initial surgery.

CONCLUSIONS

Beside the routine histological and immunohistochemical characteristics of primary ovarian leiomyosarcoma, strong staining for bcl-2 was detected. In order to understand more about the nature and the behaviour of this highly malignant neoplasm and to be able to improve the treatment, the prognostic value of bcl-2 has to be investigated in additional studies.

Oral leiomyosarcoma: review of the literature and report of two cases with assessment of the prognostic and diagnostic significance of immunohistochemical and molecular markers

Leiomyosarcoma of the oral cavity is a very rare tumor that is associated with aggressive clinical behavior and low survival. In this paper, we report two new cases of leiomyosarcoma affecting the mandibular gingiva and mandible of a 35-year-old male and the mandible of a 51-year-old female. Given the difficulty in the histopathologic discrimination between benign and malignant smooth muscle tumors and the absence of reliable histologic parameters for prognostication of leiomyosarcomas, we evaluated the diagnostic and prognostic value of various immunohistochemical and molecular markers. By means of immunohistochemistry and quantitative real-time PCR analysis, we detected protein expression of PCNA, bcl-2, CDK4, p53 and MDM2 in both our cases and MDM2 amplification in our second case. The literature, pertinent to oral leiomyosarcoma and to molecular analysis of smooth muscle tumors, is reviewed.

The values of intratumoral mast cell count and Ki-67 immunoreactivity index in differential diagnosis of uterine smooth muscle neoplasms

In this study, the role of the count of intratumoral mast cells was examined and compared with the proliferative activity exhibited by Ki-67 indices in the differential diagnosis of uterine smooth muscle tumors. Sixteen cases of leiomyosarcoma, nine cases of atypical leiomyoma and 16 cases of ordinary leiomyoma were included. The pathological features of the cases were determined by reviewing the archive materials including the patient records and hematoxylin-eosin-stained sections. Toluidine blue stain was used to highlight the intratumoral mast cells and they were counted in at least 40 high power fields. A standard streptavidin-biotin method was applied to the sections to highlight the Ki-67 immunoreactive tumor cell nuclei. These proliferative cells were counted in at least 10 high-power fields. Atypical leiomyomas tended to have a higher quantity of intratumoral mast cells than leiomyosarcomas and ordinary leiomyomas (P = 0.027 and P = 0.021, respectively). Leiomyosarcomas tended to have higher Ki-67 immunoreactivity rates than atypical leiomyomas, although the difference was not statistically significant (P = 0.82). We concluded that the quantity of intratumoral mast cells is useful in the differential diagnosis between leiomyosarcomas and atypical leiomyomas, while the cell proliferation rate expressed by Ki-67 immunoreactivity has a limited value.

MIB-1 (Ki-67), p53, estrogen receptor, and progesterone receptor expression in uterine smooth muscle tumors

The diagnosis of benign, uncertain malignant potential, and malignant uterine smooth muscle tumors depends on mitotic counts, nuclear atypia, and other morphologic features. This study was undertaken to evaluate the utility of selected immunohistochemical markers in differentiating these tumors. Fifteen cases of cellular leiomyoma, 7 cases of smooth muscle tumor of uncertain malignant potential (STUMP), and 12 cases of leiomyosarcoma were immunostained for MIB-1 (Ki-67), p53, estrogen receptor and progesterone receptor (PR) using monoclonal antibodies and the avidin-biotin-peroxidase method. The percentage of cells stained was subjectively assessed to the nearest 5%. One percent was used for rare positive cells. MIB-1 expression of > or =15% was seen in 11 and expression of p53 in > or =15% cells was present in 5 of 12 leiomyosarcomas. MIB-1 and/or p53 expression of >15% was seen in all 12 leiomyosarcomas but in none of the 7 STUMP or 15 cellular leiomyomas. PR was absent in 10 of 12 leiomyosarcomas but present in 7 of 7 STUMP and 14 of 15 cellular leiomyomas. MIB-1 of 5% to 10% was seen in 6 of 7 STUMP but in only 1 of 15 cellular leiomyomas. MIB-1, p53, and PR are useful in differentiating leiomyosarcoma from STUMP and cellular leiomyoma. MIB-1 is useful in distinguishing STUMP from cellular leiomyomas.

Frequent occurrence of loss of heterozygosity among tumor suppressor genes in uterine leiomyosarcoma

OBJECTIVE

Leiomyosarcoma of the uterus is a rare smooth muscle tumor; it is extremely malignant and the rates of local recurrence and metastasis are high. Since tumor suppressor genes are commonly altered in malignant tumors, it is possible that mutations in such genes are involved in the development of uterine leiomyosarcoma.

METHODS

Fifty-five patients (37-70 years of age) diagnosed as having smooth muscle tumors of the uterus were selected. DNA was extracted from four or five 8-microm-thick consecutive tissue sections of each smooth muscle tumor from the paraffin-embedded blocks. Loss of heterozygosity (LOH) was investigated at nine loci within or close to tumor suppressor genes (TP53, RB1, DCC, NM23, WT1, D14S267, P16, DPC4, PTCH).

RESULTS

Nineteen of twenty leiomyosarcomas revealed at least one instance of LOH among eight of the nine markers tested (one locus showed no LOH at all). In fact, 11 of the 20 cases exhibited two or more instances of LOH and, of the remaining 9 cases, 4 showed a point mutation of p53 in addition to an alteration in one of the 9 markers, while one exhibited a p53 mutation only.

CONCLUSION

An accumulation of genetic alterations among tumor suppressor genes may play a key role in the tumorigenesis and progression of uterine leiomyosarcoma.