Expression of Transforming Growth Factor β Isoforms and Their Receptors in Malignant Fibrous Histiocytoma of Soft Tissues

Role and clinical significance of TGF‑β1 and TGF‑βR1 in malignant tumors (Review)

The appearance and growth of malignant tumors is a complicated process that is regulated by a number of genes. In recent years, studies have revealed that the transforming growth factor-β (TGF-β) signaling pathway serves an important role in cell cycle regulation, growth and development, differentiation, extracellular matrix synthesis and immune response. Notably, two members of the TGF-β signaling pathway, TGF-β1 and TGF-β receptor 1 (TGF-βR1), are highly expressed in a variety of tumors, such as breast cancer, colon cancer, gastric cancer and hepatocellular carcinoma. Moreover, an increasing number of studies have demonstrated that TGF-β1 and TGF-βR1 promote proliferation, migration and epithelial-mesenchymal transition of tumor cells by activating other signaling pathways, signaling molecules or microRNAs (miRs), such as the NF-κB signaling pathway and miR-133b. In addition, some inhibitors targeting TGF-β1 and TGF-βR1 have exhibited positive effects in in vitro experiments. The present review discusses the association between TGF-β1 or TGF-βR1 and tumors, and the development of some inhibitors, hoping to provide more approaches to help identify novel tumor markers to restrain and cure tumors.

LRRC15 Targeting in Soft-Tissue Sarcomas: Biological and Clinical Implications

BACKGROUND

LRRC15 is a member of the LRR (leucine-rich repeat) superfamily present on tumor-associated fibroblasts (CAFs) and stromal cells. The expression of LRRC15 is upregulated by the pro-inflammatory cytokine TGFβ. ABBV-085 is a monomethyl auristatin E (MMAE)-containing antibody-drug conjugate (ADC) designed to target LRRC15, and which has shown significant anti-tumor activity in several tumor models. This is the first focused examination of LRRC15 expression and ABBV-085 activity in soft-tissue sarcomas (STS).

METHODS

We analyzed the LRRC15 expression profile by immunohistochemistry in 711 STS cases, covering a broad spectrum of STS histologies and sub-classifications. In vivo experiments were carried out by using LRRC15-positive and LRRC15-negative patient-derived xenograft (PDX) models of STS.

RESULTS

In contrast to patterns observed in epithelial tumors, LRRC15 was expressed not only by stromal cells but also by cancer cells in multiple subsets of STS with significant variations noted between histological subtypes. Overexpression of LRRC15 is positively correlated with grade and independently associated with adverse outcome. ABBV-085 has robust preclinical efficacy against LRRC15 positive STS patient-derived xenograft (PDX) models.

CONCLUSION

We provide the first preclinical evidence that LRRC15 targeting with an antibody-drug conjugate is a promising strategy in LRRC15-positive STS. ABBV-085 is being evaluated in an ongoing clinical trial in STS and other malignancies.

TGFβ and Hippo Pathways Cooperate to Enhance Sarcomagenesis and Metastasis through the Hyaluronan-Mediated Motility Receptor (HMMR)

High-grade sarcomas are metastatic and pose a serious threat to patient survival. Undifferentiated pleomorphic sarcoma (UPS) is a particularly dangerous and relatively common sarcoma subtype diagnosed in adults. UPS contains large quantities of extracellular matrix (ECM) including hyaluronic acid (HA), which is linked to metastatic potential. Consistent with these observations, expression of the HA receptor, hyaluronan-mediated motility receptor (HMMR/RHAMM), is tightly controlled in normal tissues and upregulated in UPS. Moreover, HMMR expression correlates with poor clinical outcome in these patients. Deregulation of the tumor-suppressive Hippo pathway is also linked to poor outcome in these patients. YAP1, the transcriptional regulator and central effector of Hippo pathway, is aberrantly stabilized in UPS and was recently shown to control RHAMM expression in breast cancer cells. Interestingly, both YAP1 and RHAMM are linked to TGFβ signaling. Therefore, we investigated crosstalk between YAP1 and TGFβ resulting in enhanced RHAMM-mediated cell migration and invasion. We observed that HMMR expression is under the control of both YAP1 and TGFβ and can be effectively targeted with small-molecule approaches that inhibit these pathways. Furthermore, we found that RHAMM expression promotes tumor cell proliferation and migration/invasion. To test these observations in a robust and quantifiable in vivo system, we developed a zebrafish xenograft assay of metastasis, which is complimentary to our murine studies. Importantly, pharmacologic inhibition of the TGFβ-YAP1-RHAMM axis prevents vascular migration of tumor cells to distant sites. IMPLICATIONS: These studies reveal key metastatic signaling mechanisms and highlight potential approaches to prevent metastatic dissemination in UPS.YAP1 and TGFβ cooperatively enhance proliferation and migration/invasion of UPS and fibrosarcomas.

Extrahepatic Upregulation of Transforming Growth Factor Beta 2 in HCV Genotype 4-Induced Liver Fibrosis

Elevated levels of transforming growth factor-β (TGF-β) family mediate myofibroblast generation and extracellular matrix deposition, thus making TGF-β recognized as major profibrogenic cytokines. In this article, we provide evidence that extrahepatic TGF-β2 expression at RNA and protein levels in peripheral leucocytes and serum, respectively, correlate with hepatic fibrogenesis. Current study includes a total of 110 subjects [89 naive hepatitis C virus (HCV)-infected patients (f0-f4) and 21 healthy controls]. Array profiling of 84 fibrosis-related transcripts revealed that TGF-β2 RNA was significantly upregulated compared with controls. Transcription results were confirmed by specific qRT-PCR on TGF-β2 RNA in peripheral leucocytes and TGF-β2 protein by ELISA in serum. PCR array and qRT-PCR for TGF-β2 RNA in peripheral leucocytes revealed that HCV-infected patients, regardless of the degree of fibrosis, had significantly elevated TGF-β2 RNA levels compared with controls (P = 0.018 and 0.047, respectively). This extrahepatic upregulation of TGF-β2 RNA was confirmed by elevated levels of secretory TGF-β2 protein in infected sera (P = 0.001). The Area Under the Curve of the receiver operating characteristic curve for the TGF-β2 protein between patients and controls was 0.80, a value that renders serum TGF-β2 protein a promising biomarker for liver fibrosis.

Inflammatory malignant fibrous histiocytoma associated with leukemoid reaction or leukocytosis: a comprehensive review

Inflammatory malignant fibrous histiocytoma (IMFH) associated with leukemoid reaction (LR)/leukocytosis is a rare entity. In this paper, we search PubMed for all known cases of IMFH associated with LR/leukocytosis in an attempt to draw conclusions about this variant's response to treatments and its pathophysiology. Medline electronic database was searched using key words such as malignant fibrous histiocytoma, leukemoid reaction, and leukocytosis. A total of 16 patients were found, twelve males (75%) and 4 female (25%), with a mean age of 62.6 years, ranging from 47 to 77. The mean survival was 770 days, ranging from 14 to 6570 days. Four patients were alive at last follow-up: 6570 days, 1095 days, 335 days, and 180 days, respectively. Of the 12 patients that expired, death occurred approximately 92 days after the onset of LR or leukocytosis, ranging from 3 to 334 days. We conclude that IMFH associated with LR/leukocytosis does not completely respond to chemoradiation. Overproduction of growth factors and cytokines by IMFH cells and their interactions with the inflammatory infiltrate seem to promote immunological effector cell's dysfunction and substantiate the development and growth of this neoplasm. A clear understanding of these molecular pathways is crucial in order to identify targets for potential therapy.

Cutaneous inflammatory malignant fibrous histiocytoma presenting with a leukemoid reaction: a case report and review of the literature

Malignant fibrous histiocytoma (MFH) is the most common sarcoma found in adults. We discuss a case of inflammatory MFH of dermal/epidermal origin presenting with a severe leukemoid reaction (LR). A 60 years old white male presented to hematology/oncology clinic complaining of mild shortness of breath on exertion. Past medical history was remarkable for removal of a left upper extremity necrotic mass 4.4 × 3 × 3 cm. Microscopy of the specimen showed clear surgical margin, and tumor cells restricted to the dermis without lymphovascular invasion. Immunohistochemestry was positive for CD 68 and CD 99. Chest x-ray was negative for metastatic disease. White blood cell count was 109.4 k/mm(3) with 24 k/mm(3) band neutrophils, and absolute neutrophil count of 69 k/mm(3). CT scan of the thorax revealed numerous bilateral pulmonary nodules suspicious for metastasis. Based on these findings patient was diagnosed with metastatic cutaneous IMFH associated with a LR. Following review of medical literature, this appears to be the first reported case of inflammatory cutaneous MFH associated with LR. This histological variant is rare, and carries a poor prognosis. Thus, we would like to emphasize the need for investigating alternative therapies capable of improving the survival of these patients.

The prognostic impact of TGF-β1, fascin, NF-κB and PKC-ζ expression in soft tissue sarcomas

Aims

Transforming growth factor-β (TGF-β), fascin, nuclear factor-kappa B (NF-κB) p105, protein-kinase C-zeta (PKC-ζ), partioning-defective protein-6 (Par-6), E-cadherin and vimentin are tumor promoting molecules through mechanisms involved in cell dedifferentiation. In soft tissue sarcomas, their expression profile is poorly defined and their significance is uncertain. We aimed to investigate the prognostic impact of TGF-β1, NF-κB p105, PKC-ζ, Par-6α, E-cadherin and vimentin in non-gastrointestinal stromal tumor soft tissue sarcomas (non-GIST STSs).

Patients and Methods

Tumor samples and clinical data from 249 patients with non-GIST STS were obtained, and tissue microarrays (TMAs) were constructed for each specimen. Immunohistochemistry (IHC) was used to evaluate marker expression in tumor cells.

Results

In univariate analysis, the expression levels of TGF-β1 (P = 0.016), fascin (P = 0.006), NF-κB p105 (P = 0.022) and PKC-ζ, (P = 0.042) were significant indicators for disease specific survival (DSS). In the multivariate analysis, high TGF-β1 expression was an independent negative prognostic factor for DSS (HR = 1.6, 95% CI = 1.1–2.4, P = 0.019) in addition to tumor depth, malignancy grade, metastasis at diagnosis, surgery and positive resection margins.

Conclusion

Expression of TGF-β1 was significantly associated with aggressive behavior and shorter DSS in non-GIST STSs.

TGF-beta3 and cancer: a review

With the development of growth factors and growth factor modulators as therapeutics for a range of disorders, it is prudent to consider whether modulating the growth factor profile in a tissue can influence tumour initiation or progression. As recombinant human TGF-beta3 (avotermin) is being developed for the improvement of scarring in the skin it is important to understand the role, if any, of this cytokine in tumour progression. Elevated levels of TGF-beta3 expression detected in late-stage tumours have linked this cytokine with tumourigenesis, although functional data to support a causative role are lacking. While it has proved tempting for researchers to interpret a 'correlation' as a 'cause' of disease, what has often been overlooked is the normal biological role of TGF-beta3 in processes that are often subverted in tumourigenesis. Clarifying the role of this cytokine is complicated by inappropriate extrapolation of the data relating to TGF-beta1 in tumourigenesis, despite marked differences in biology between the TGF-beta isoforms. Indeed, published studies have indicated that TGF-beta3 may actually play a protective role against tumourigenesis in a range of tissues including the skin, breast, oral and gastric mucosa. Based on currently available data it is reasonable to hypothesize that administration of acute low doses of exogenous TGF-beta3 is unlikely to influence tumour initiation or progression.

Hepatitis C virus core protein triggers hepatic angiogenesis by a mechanism including multiple pathways

Chronic hepatitis C virus (HCV) infection is associated with the production of serum cytokines, including transforming growth factor (TGF)-beta2. Despite the occurrence of hepatic angiogenesis in liver conditions, the role of HCV proteins in this context is currently unknown. We demonstrated that the development of hepatic neoangiogenesis in patients infected with HCV is associated with the expression of TGF-beta2 and vascular endothelial growth factor (VEGF) and with activation of endothelial cells, as evidenced by CD34 expression. The analysis of liver biopsies of HCV-positive and HCV-negative patients using immunostaining showed significant elevation of TGF-beta2, VEGF, and CD34 expression in patients who were HCV-positive. Using an HCV established culture system, we confirmed further the production of both TGF-beta2 and VEGF proteins, in the hepatoma cell lines HepG2 and Huh7 by transfection with full-length HCV RNA (JFH1) or by the regulated expression of core. In addition, regulated expression of core protein in HepG2 or Huh7 cells was found to induce expression and activation of the transcription factor E2F1 and apoptosis signal-regulating kinase 1 (ASK1), activation of c-jun-N-terminal kinase (JNK) and p38, and extracellular-regulated kinase (ERK), and transcription factors activator protein 1 (AP-1), activating transcription factor 2 (ATF-2), cyclic adenosine monophosphate response element binding (CREB), E2F1, hypoxia inducing factor 1 alpha (HIF-1alpha), and specificity protein 1. Furthermore, data obtained from inhibitor experiments revealed the importance of E2F1 and ASK1 in the modulation of core-induced activation of JNK and p38 pathways and suggested an essential role for JNK, p38, and ERK pathways in the regulation of core-induced production of TGF-beta2 and VEGF proteins. Thus, our data provide insight into the molecular mechanisms whereby core protein mediates the development of hepatic angiogenesis in patients with chronic HCV infection.