Clinical & Experimental Metastasis

Diagnostics of metastasis: an increasing challenge with high clinical importance

Histopathological growth patterns of colorectal liver metastasis exhibit little heterogeneity and can be determined with a high diagnostic accuracy Abstract Colorectal liver metastases (CRLM) exhibit distinct histopathological growth patterns (HGPs) that are indicative of prognosis following surgical treatment. This study aims to assess the reliability and replicability of this histological biomarker. Within and between metastasis HGP concordance was analysed in patients who underwent surgery for CRLM. An independent cohort was used for external validation. Within metastasis concordance was assessed in CRLM with ≥ 2 tissue blocks. Similarly, concordance amongst multiple metastases was determined in patients with ≥ 2 resected CRLM. Diagnostic accuracy [expressed in area under the curve (AUC)] was compared by number of blocks and number of metastases scored. Interobserver agreement (Cohen's k) compared to the gold standard was determined for a pathologist and a PhD candidate without experience in HGP assessment after one and two training sessions. Both the within (95%, n = 825) and the between metastasis (90%, n = 363) HGP concordance was high. These results could be replicated in the external validation cohort with a within and between metastasis concordance of 97% and 94%, respectively. Diagnostic accuracy improved when scoring 2 versus 1 blocks(s) or CRLM (AUC = 95.9 vs. 97.7 [p = 0.039] and AUC = 96.5 vs. 93.3 [p = 0.026], respectively), but not when scoring 3 versus 2 blocks or CRLM (both p > 0.2). After two training sessions the interobserver agreement for both the pathologist and the PhD candidate were excellent (k = 0.953 and k = 0.951, respectively). The histopathological growth patterns of colorectal liver metastasis exhibit little heterogeneity and can be determined with a high diagnostic accuracy, making them a reliable and replicable histological biomarker.

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for endometrial cancer-derived peritoneal metastases: a systematic review Abstract Cytoreductive surgery (CRS) is an appropriate treatment for selected patients with endometrial cancer (EC)-derived peritoneal metastases (PM). Hyperthermic intraperitoneal chemotherapy (HIPEC) may enhance the therapeutic efficacy of CRS in these patients. We performed a systematic literature search of the databases PubMed and Cochrane Central Register of Controlled Trials to identify clinical trials and case reports reporting on the safety and efficacy of CRS and HIPEC in patients with EC-derived PM. Eight publications reporting on 68 patients were identified. The mean patient age was 57.1 years and the mean time from initial treatment of EC to CRS and HIPEC was 22.3 months. 41/64 patients had adenocarcinomas, type II cancers were present in 23/64 patients. The mean peritoneal carcinomatosis index (PCI) was 16.7. A complete surgical resection CC-0 was achieved in 44/63 (70%) patients. The chemotherapy regimens used for HIPEC were variable, but all included cisplatin, administered either alone (39/68 patients) or combined with doxorubicin or paclitaxel or mitomycin (29/68 patients). The duration of HIPEC was 60 min in 51/68 patients and 90 min in 17/68 patients. Mostly, the closed technique was used (55/68 patients). Adverse events grades 1/2, 3, and 4 were observed in 23/63, 12/63, and 6/63 patients, respectively. Treatment-associated mortality was 1% (1/63). After CRS and HIPEC, most patients received systemic chemotherapy (46/63 patients). Median disease-free and overall survival ranged from 7 to 18 and 12 to 33 months, respectively. In conclusion, CRS and HIPEC in EC with PM is safe and feasible. An additional therapeutic value of HIPEC is suggested, but prospective comparative trials are warranted.

Metastasis is impaired by endothelial-specific Dll4 loss-of-function through inhibition of epithelial-to-mesenchymal transition and reduction of cancer stem cells and circulating tumor cells Abstract Systemic inhibition of Dll4 has been shown to thoroughly reduce cancer metastasis. The exact cause of this effect and whether it is endothelial mediated remains to be clarified. Therefore, we proposed to analyze the impact of endothelial Dll4 loss-of-function on metastasis induction on three early steps of the metastatic process, regulation of epithelial-to-mesenchymal transition (EMT), cancer stem cell (CSC) frequency and circulating tumor cell (CTC) number. For this, Lewis Lung Carcinoma (LLC) cells were used to model mouse tumor metastasis in vivo, by subcutaneous transplantation into endothelial-specific Dll4 loss-of-function mice. We observed that endothelial-specific Dll4loss-of-function is responsible for the tumor vascular regression that leads to the reduction of tumor burden. It induces an increase in tumoral blood vessel density, but the neovessels are poorly perfused, with increased leakage and reduced perivascular maturation. Unexpectedly, although hypoxia was increased in the tumor, the number and burden of macro-metastasis was significantly reduced. This is likely to be a consequence of the observed reduction in both EMT and CSC numbers caused by the endothelial-specific Dll4 loss-of-function. This multifactorial context may explain the concomitantly observed reduction of the circulating tumor cell count. Furthermore, our results suggest that endothelial Dll4/Notch-function mediates tumor hypoxia-driven increase of EMT. Therefore, it appears that endothelial Dll4 may constitute a promising target to prevent metastasis.

The clinical outcome of eribulin treatment in Japanese patients with advanced soft tissue sarcoma: a Tokai Musculoskeletal Oncology Consortium study Abstract The efficacy and safety of eribulin in Japanese patients with advanced soft-tissue sarcomas (STS) have not been evaluated in a large-scale cohort study. Thus, we aimed to investigate the clinical outcome of 82 Japanese patients with STS receiving eribulin across multiple study centers retrospectively. Of 82 STS patients receiving eribulin treatment, 13 were treated for locally unresectable tumor, 46 for metastasis, and 23 for both. The primary endpoint of this study was to evaluate the efficacy of eribulin against STS. The median age was 60 years. Thirty-seven were diagnosed with L-sarcoma (leiomyosarcoma or liposarcoma) and 45 had non-L-sarcoma. The median progression-free survival (PFS) for all patients was 2.7 months, with 3.4 months in those with L-sarcoma and 2.2 months in those with non-L-sarcoma. Patients with L-sarcoma showed a better PFS than those with non-L-sarcoma. Overall, the median survival time was 11.1 months, and 12.3 months and 7.9 months in patients with L-sarcoma and non-L-sarcoma, respectively; however, there was no significant differences between the groups. The prognostic significance of PS = 0 and both existence of local and metastatic STS was evaluated by multivariate analysis. We also evaluated the overall survival (OS) in patients with undifferentiated pleomorphic sarcoma (UPS) and other non-L-sarcomas. Patients with UPS had better OS than those with the other non-L-sarcomas. In conclusion, there was a significant difference in PFS between patients with L-sarcoma and non-L-sarcoma following treatment with eribulin. The anti-tumor potential of eribulin was evident in patients with UPS.

CTHRC1 promotes M2-like macrophage recruitment and myometrial invasion in endometrial carcinoma by integrin-Akt signaling pathway Abstract The infiltration of tumor-associated macrophages (TAMs) is associated with tumor progression and poor prognosis in endometrial cancer (EC). Collagen triple helix repeat containing 1 (CTHRC1), a secreted ECM protein, has been reported to have important roles in promoting cancer invasion and metastasis, but the functional role of CTHRC1 and its association with TAMs in EC remain unclear. Here we report that, in EC patients, CTHRC1 expression was up-regulated in endometrial cancer tissues compared with normal endometrium (P < 0.0001), and is positively correlated with tumor grade and depth of myometrial invasion (P = 0.024 and P = 0.0002, respectively). Meanwhile, CTHRC1 expression was positively correlated with an increased number of infiltrating TAMs, especially M2-like TAMs (P = 0.003, P = 0.001). In the tumor microenvironment of EC, CTHRC1 not only promoted myometrial invasion by interacting with Integrin β3-Akt signaling pathway, but also promoted infiltration of M2-like TAMs by upregulating Fractalkine chemokine receptor (CX3CR1) expression in macrophages. Changing levels of recombinant CTHRC1 protein (rCTHRC1) promoted tumor migration and invasion via enhancing macrophage recruitment in vitro. In summary, our findings eventually provided a novel role for CTHRC1 in remodeling the tumor immune microenvironment to promote tumor metastasis in EC patients.

Stereotactic radiation therapy in oligometastatic colorectal cancer: outcome of 102 patients and 150 lesions Abstract To evaluate the local control (LC), progression free survival (PFS), out-field PFS, overall survival (OS), toxicity and failure predictors of SRT in a series of various sites oligometastatic CRC patients. Patients with oligometastatic CRC disease were analyzed retrospectively. The SRT prescribed dose was dependent on the lesion volume and its location. 102 consecutive oligometastatic CRC patients (150 lesions) were included. They underwent SRT between 2012 and 2015. Median prescription dose was 45 Gy (median dose/fraction was 15 Gy/3 fractions biological equivalent dose (BED10) 112.5 Gy). Median follow-up was 11.4 months. No patients experienced G3 and G4 toxicity. No progression was found in 82% (radiological response at 3 months) and 85% (best radiological response) out of 150 evaluable lesions. At 1 and 2 years: LC was 70% and 55%; OS was 90% and 90%; PFS was 37% and 27%; out-field PFS was 37% and 23% respectively. Progressive disease was correlated with BED10 (better LC when BED10 was ≥ 75 Gy (p < 0.0001)). In multivariate analysis, LC was higher in lesions with a Plpnning target volume (PTV) volume < 42 cm3 and BED10 ≥ 75 Gy. Patients with Karnofsky performance status < 90 showed higher out-field progression. SRT is an effective treatment for patients with oligometastases from CRC. Its low treatment-associated morbidity and acceptable LC make of SRT an option not only in selected cases. Further studies should be focused to clarify which patient subgroup will benefit most from this treatment modality and to define the optimal dose to improve LC while maintaining low toxicity profile.

Hypermethylation-mediated inactivation of miR-124 predicts poor prognosis and promotes tumor growth at least partially through targeting EZH2/H3K27me3 in ESCC Abstract Accumulating evidences indicated that some microRNAs (miRNAs) play a critical role during the carcinogenesis. In the present study, we found that miR-124 is down-regulated in esophageal squamous cell carcinoma (ESCC) tissues. Three miR-124 encoding genes, including mir-124-1, mir-124-2, and mir-124-3, harboring CpG islands undergo methylation-mediated miR-124 inactivation in ESCC tissues. The methylation status of all these three genes was negatively associated with the expression of miR-124. The low expression of miR-124 and the hypermethylation of mir-124-1 and mir-124-3 were associated with the clinico-pathological parameters indicating the poor prognosis. In addition, promoter methylation of all three genes plus low expression of miR-124 was the independent poor prognostic marker for ESCC patients. In conclusion, miR-124 may function as a tumor suppressive miRNA, and hypermethylation-mediated inactivation of miR-124 may be useful for a poor prognostic marker for ESCC patients.

Identification of S100A14 as a metastasis-promoting molecule in a murine organotropic metastasis model Abstract Cancer metastasis shows great diversity in target organs, routes and molecular mechanisms depending on the type of cancer and even on the individual patients. To identify key molecules involved in metastasis, we constructed a murine model system including multiple sublines with different organotropism and pathways of metastasis. We selected metastatic sublines from a murine mammary tumor cell line MCH66. Using this model, we extracted metastasis-related molecules by gene expression screening methods and verified their metastasis-promoting effects by gene knockdown or overexpression experiments. For the candidates promoting metastasis, we analyzed molecular functions involved in metastasis: cell growth, motility and invasive activity. We established a metastasis model including low metastatic sublines (66C8, 66LM, 66-4) and highly metastatic counterparts with various organotropism, such as to the lung (66Lu10), liver (HM-KAN5) and general organs (66HM and its clones: HM1-6 and HM1-7). The sublines basically exhibited the invasion-independent metastasis pathway characterized by endothelial cell-covered tumor emboli, whereas 66HM and HM-KAN5 showed an alternative metastasis pathway based on invasion in part and in whole, respectively. Comprehensive gene analysis extracted several molecular candidates responsible for metastasis. S100A14 was identified as one of the promissing candidates promoting lung-metastasis, which was verified by gene knockdown experiments in vivo. In addition, in vivo and in vitro functional analyses demonstrated that S100A14 enhanced scattering, motility and invasiveness of mouse tumor cells. Our model system may be adaptable to the diversity of metastasis in human cancers and useful for exploring the molecular mechanism responsible for metastasis.

The importance of developing therapies targeting the biological spectrum of metastatic disease Abstract Great progress has been made in cancer therapeutics. However, metastasis remains the predominant cause of death from cancer. Importantly, metastasis can manifest many years after initial treatment of the primary cancer. This is because cancer cells can remain dormant before forming symptomatic metastasis. An important question is whether metastasis research should focus on the early treatment of metastases, before they are clinically evident ("overt"), or on developing treatments to stop overt metastasis (stage IV cancer). In this commentary we want to clarify why it is important that all avenues of treatment for stage IV patients are developed. Indeed, future treatments are expected to go beyond the mere shrinkage of overt metastases and will include strategies that prevent disseminated tumor cells from emerging from dormancy.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com