Increased expression of platelet derived growth factor receptor β on trephine biopsies correlates with advanced myeloma

PURPOSE

Multiple myeloma (MM), a major cause of cancer mortality, is considered the second most frequent haematological malignancy in Europe. Angiogenesis is a multifactorial process that drives the tumorigenesis in solid tumors and in MM. The platelet derived growth factor (PDGF) receptors are cell surface tyrosine kinase receptors and play an important role in angiogenesis, cancer cell proliferation and dissemination. Few studies have been conducted regarding the expression of PDGF receptors and the correlation with clinical-pathological parameters and prognosis in MM. The purpose of our study was to evaluate, for the first time, in a large cohort of newly-diagnosed MM (NDMM) patients, the expression of PDGF receptor α and β (PDGFR α, β) in bone marrow trephine biopsies and investigate the association of PDGFR α, PDGFR β with angiogenesis in the bone marrow, assessed by bone marrow microvessel density (MVD), clinical characteristics and prognosis.

METHODS

In this retrospective study, we assessed the relation of PDGFR α and PDGFR β immunohistochemical expression with MVD in formalin-fixed paraffin-embedded bone marrow sections from 120 NDMM patients. The immunoreactivity of PDGFR α and β was examined on the basis of positive plasma cells (PCs) with specific cut off values.

RESULTS

PDGFRα and PDGFRβ were frequently expressed on malignant PCs. We found that increased PDGFRβ expression was strongly associated with advanced disease and adverse prognosis. The expression of PDGFRα and MDV were not correlated with specific features.

CONCLUSION

This analysis showed highly expressed PDGFRα and β PCs of NDMM patients and indicated that high PDGFRβ expression at diagnosis was associated with advanced-stage disease.

Abstract P5-07-06: Kinase-independent role of cyclin D1 in chromosomal instability and mammary tumorigenesis

Cyclin D1 is an important molecular driver of human breast cancer but better understanding of its oncogenic mechanisms is needed, especially to enhance efforts in targeted therapeutics. Activation of the cyclin D1 oncogene, often by amplification or rearrangement, is a major driver of multiple types of human tumors including breast and squamous cell cancers, B-cell lymphoma, myeloma, and parathyroid adenoma. The cyclin D1 gene is amplified or overexpressed in up to half of human breast cancers and its mammary-targeted overexpression induces mammary tumorigenesis in mice. Cyclin D1 encodes the regulatory subunit of the cyclin-dependent kinase (CDK) holoenzyme that phosphorylates several substrates including the retinoblastoma protein (pRb) to advance the G1S cell cycle checkpoint, promote DNA synthesis and regulate NRF-1 to inhibit mitochondrial biogenesis thereby coordinating nuclear and mitochondrial functions.

In addition to cyclin D1's function as a regulatory subunit of a CDK holoenzyme, several CDK-independent functions have been identified. Tumors overexpressing cyclin D1 tend to display normal levels of proliferation and expression of E2F target genes, which contrasts with tumors overexpressing cyclin E or an activator for pRb. Breast cancers overexpressing cyclin D1 that are wild type for pRb have relatively normal proliferation rates, in contrast to those caused by genetic inactivation of pRb, which show significantly increased proliferation rates. Furthermore, the alternate splice form of cyclin D1, (cyclin D1b), has potent transforming ability, which does not correlate with the ability to phosphorylate the pRb protein. Several other properties of cyclin D1 have been identified including the induction of cellular migration and enhanced angiogenesis, inhibition of mitochondrial biogenesis, and mediating DNA-damage repair signaling. Cyclin D1 binding proteins participating in these putatively CDK-independent functions include PACSIN2, NRF1, and p27KIP1; binding to p27KIP1 and PACSIN2 contribute to the pro-migratory function of cyclin D1.

Currently, pharmaceutical initiatives to inhibit cyclin D1 are focused on the catalytic component since the transforming capacity is thought to reside in the cyclin D1/CDK activity. We initiated the following study to directly test the oncogenic potential of catalytically inactive cyclin D1 in an in vivo mouse model that is relevant to breast cancer. Herein, transduction of cyclin D1-/- mouse embryonic fibroblasts (MEFs) with the kinase dead KE mutant of cyclin D1 led to aneuploidy, abnormalities in mitotic spindle formation, autosome amplification, and chromosomal instability (CIN) by gene expression profiling. Acute transgenic expression of either cyclin D1WT or cyclin D1KE in the mammary gland was sufficient to induce the CIN signature within 7 days. Sustained expression of cyclin D1KE induced mammary adenocarcinoma with similar kinetics to that of the wild-type cyclin D1. ChIP-Seq studies demonstrated recruitment of cyclin D1WT and cyclin D1KE to the genes governing CIN. We conclude that the CDK-activating function of cyclin D1 is not necessary to induce either chromosomal instability or mammary tumorigenesis.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-07-06.

Primary angiosarcoma of bone. A case report

BACKGROUND

Primary malignant vascular tumors of bone are very rare accounting for less than 1% of primary bone malignancies. They are characterized by unknown etiology, variable biologic behavior and histological appearance. Angiosarcoma is an aggressive malignant vascular tumor derived from mesenchymal cells with endothelial differentiation.

CASE REPORT

We present a rare case of angiosarcoma of bone in a 47-year-old male operated for a lumbar disk herniation. During his transportation from the operation theater, a pathological intertrochanteric fracture of the right hip occured. The magnetic resonance imaging (MRI) revealed a bone lytic lesion located into the great trochanter of the right femur. Open surgical biopsy of the lesion was performed and the histological examination showed primary angiosarcoma of bone. The treatment included radiotherapy (300 cGy per fraction in 13 days) followed by excision of the proximal femur and custom made total hip arthroplasty. The diagnosis was confirmed on the surgical specimen.

Oral Mucositis: understanding the pathology and management

Oral Mucositis is a common complication of cancer therapy which may limit the completion of treatment and affect the quality of life of the patient. As we have come to understand its pathogenesis new developments in its management and prevention have allowed us minimize this side effect.

Primary ovarian small cell carcinoma of pulmonary type with enlarged paraaortic lymph node masses: a case report and review of the literature

INTRODUCTION

Small cell carcinoma of the ovary of pulmonary type, is a rare, aggressive tumour with poor prognosis and its optimal management is unclear.

CASE PRESENTATION

A 55-year-old Caucasian woman presented with abdominal discomfort and left lumbar pain within a three-week period. At exploratory laparotomy, a 8 cm solid cystic mass of the left ovary was found infiltrating the sigmoid colon, and a bulky mass (11 x 7 x 4 cm) in the left paraaortic infrarenal region. Histopathological features resembling small cell carcinoma of the lungs and positive immunohistochemical stains provided a definite diagnosis of IIIC ovarian small cell carcinoma of pulmonary type. After six cycles chemotherapy with carboplatin and etoposide, the patient is still alive at 21 months from initial diagnosis.

DISCUSSION

In this case, the absence of peritoneal involvement and the extensive paraaortic adenopathy is suggestive of a different pattern of spread of this rare tumour. Optimal treatment seems to be radical primary debulking surgery resulting in no residual disease, maximizing the effect of adjuvant chemotherapy for this biological aggressive tumour.

Increased serum C-reactive protein levels in normal weight women with polycystic ovary syndrome

BACKGROUND

The clinical spectrum of polycystic ovary syndrome (PCOS) includes components of the metabolic syndrome, such as central obesity, insulin resistance, dyslipidemia, arterial hypertension and, even, disturbances of the clotting mechanism. All these disorders are epidemiologically related to cardiovascular disease, most probably through low-grade intravascular chronic inflammation. The aim of this study was to evaluate the serum concentrations of high sensitivity C-reactive protein (hsCRP), a non-specific marker of low-grade inflammation and a predictive marker for cardiovascular disease, in normal weight women with (PCOS).

PATIENTS AND METHODS

One hundred and eighty-eight (188) normal weight [body mass index (BMI) < 25 kg/m(2)] women with PCOS were included in the study. Forty-three (43) normal weight women without PCOS (normal ovulation without clinical or biochemical hyperandrogenemia) served as controls. Serum samples for luteinizing hormone, folliclestimulating hormone, prolactin, total testosterone, Δ4-androstenedione, 17α-hydroxy-progesterone, sex hormone-binding globulin (SHBG), insulin, glucose and hsCRP were collected in early follicular phase (third to sixth day) of a menstrual cycle in the control group or during a spontaneous bleeding episode in the PCOS group.

RESULTS

Normal weight women with PCOS had higher concentrations of serum hsCRP as compared to normal weight women without PCOS (mean ± standard error of the mean 0.55 ± 0.08 versus 0.27 ± 0.08 mg/dL, p = 0.001).

CONCLUSIONS

As normal weight women with PCOS are characterized by elevated serum concentrations of hsCRP, they have to be considered as carrying at least one marker of low-grade inflammation.