Correlation of the expression of vascular endothelial growth factor and its receptors with microvessel density in ovarian cancer

Macrophages in ovarian cancer and their interactions with monoclonal antibody therapies

The unmet clinical need for effective treatments in ovarian cancer has yet to be addressed using monoclonal antibodies (mAbs), which have largely failed to overcome tumour-associated immunosuppression, restrict cancer growth, and significantly improve survival. In recent years, experimental mAb design has moved away from solely targeting ovarian tumours and instead sought to modulate the wider tumour microenvironment (TME). Tumour-associated macrophages (TAMs) may represent an attractive therapeutic target for mAbs in ovarian cancer due to their high abundance and close proximity to tumour cells and their active involvement in facilitating several pro-tumoural processes. Moreover, the expression of several antibody crystallisable fragment (Fc) receptors and broad phenotypic plasticity of TAMs provide opportunities to modulate TAM polarisation using mAbs to promote anti-tumoural phenotypes. In this review, we discuss the role of TAMs in ovarian cancer TME and the emerging strategies to target the contributions of these cells in tumour progression through the rationale design of mAbs.

Epstein-Barr virus is a promoter of lymphoma cell metastasis

It is well-known that Epstein-Barr virus (EBV) is the promoter of cell tumourigenesis. We found that EBV is also a promoter of lymphoma cell dissemination, because we found the typical morphopathological phenomenon of cell adhesion, which confirmed that the adhesion of tumour cells was higher than that of normal cells. We also observed that tumour cells disrupted the dynamic pathological changes of vascular endothelial cells, and this made it clear that the rate of tumour cell metastasis was directly proportional to the degree of EBV infection. Furthermore, when we discovered exosomes, it was considered that this was associated with cancer stem cells, suggesting the formation of a microenvironment before tumour cell metastasis. In addition, competitive inhibition was found in cell adhesion, indicating the breakthrough point of preventing tumour cell metastasis, which has clinical reference value for tumour immunotherapy.

MicroRNA-126 affects ovarian cancer cell differentiation and invasion by modulating expression of vascular endothelial growth factor

Primary ovarian cancer is the main cause of gynecological cancer-associated mortality. However, the mechanism behind the spread of ovarian cancer requires elucidation. The present study aimed to investigate the effects of microRNA-126 (miR-126) on differentiation and invasion, and its mechanism in primary ovarian cancer. Ovarian cancer SKOV3 cells transfected with LV3-has-miR-126 mimics and LV3-has-miR-126 inhibitor were produced; it was revealedthatLV-miR-126 mimics could induce cell cycle arrest at G₁ phase, suppress cell invasion through Matrigel-coated membranes and downregulate the expression of vascular endothelial growth factor (VEGF). Furthermore, LV-has-miR-126 inhibitor-transfected cells could increase the number of cells in S phase, induce cell invasion and upregulate the expression of VEGF. The present study, to the best of our knowledge, is the first to report that miR-126 may serve tumor suppressor roles by inducing G₁ cell cycle arrest and suppressing invasion in ovarian cancer cells, at least in part by targeting VEGF expression.

PARP-1 may be involved in angiogenesis in epithelial ovarian cancer

Poly (ADP-ribose) polymerase 1 (PARP-1) is involved in DNA repair and has been implicated in chemoresistance. The present study investigated whether PARP-1 promotes angiogenesis in ovarian cancer. PARP-1 and vascular endothelial growth factor A (VEGF-A) expression and CD34⁺ microvascular density (MVD) were assessed using immunohistochemistry in 60 human epithelial ovarian cancer specimens. PARP-1 was stably knocked-down in SKOV3 cells using a specific small interfering RNA (siRNA); angiogenic capacity was assessed using the human umbilical vein endothelial cell (HUVEC) tubule formation assay; and PARP-1 and VEGF-A expression were examined by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA. PARP-1 was found to be expressed in 73.3% (44/60) of the human epithelial ovarian cancer specimens and was significantly associated with VEGF-A, MVD, tumor size, histological grade and lymphatic metastasis (P<0.05). Compared with cells transfected with a negative control siRNA, knockdown of PARP-1 significantly suppressed the ability of SKOV3 cell-conditioned media to promote HUVEC tubule formation on Matrigel in vitro. Knockdown of PARP-1 in SKOV3 cells also significantly reduced VEGF-A mRNA and protein expression and secretion. In summary, PARP-1 is overexpressed and may enhance angiogenesis in epithelial ovarian cancer by upregulating VEGF-A.

Indirect and competitive enzyme-linked immunosorbent assays for monitoring the humoral response against human VEGF

CIGB-247, a VEGF-based vaccine, was studied in a clinical trial. This advance demands the refinement of the methodologies for assessment of vaccine immune responses. This study aimed to improve the performance of ELISAs for detecting IgG antibodies against human VEGF and the blocking activity of the serum to inhibit the VEGF/VEGFR2 interaction. The best experimental conditions were established through the evaluation of several blocking buffers, immobilization surfaces, and plate suppliers using human sera as test samples. As a result, two controlled ELISAs were used in testing of elicited immune response against VEGF in patients immunized with CIGB-247.

Factors influencing improvement of visual field after trans-sphenoidal resection of pituitary macroadenomas: a retrospective cohort study

AIM

To investigate the influencing factors of visual field improvement after trans-sphenoidal resection of pituitary macroadenomas.

METHODS

This retrospective cohort study included 201 patients (366 eyes) with visual field defect induced by pituitary macroadenomas. All of them were treated with trans-sphenoidal surgery. Ophthalmologic evaluation, best-corrected visual acuity (BCVA), and visual field examination were performed before and 3mo after surgery. BCVA, visual field defect index mean deviation (MD), duration of symptoms, age, sex, and volume of tumors were compared. Expression of vascular endothelial growth factor (VEGF) and Ki-67 of tumor tissue were detected by immunohistochemical technique.

RESULTS

The mean age of patients was 44.23±1.29y. Ninety-three patients were female and 108 were male. The mean tumor volume was 14.36±6.23 cm(3). The mean duration of preoperative symptoms was 11.50±0.88mo. Mean preoperative MD was -17.50±0.82 dB. Mean Preoperative visual acuity was 0.64±0.04. Postoperative visual field improved in 270 (73.77%) eyes, unchanged in 96 (26.23%) eyes. Multivariate logistic regression displayed that the factors independently influencing visual field improvement were young age (OR=1.71, 95%CI: 1.325-2.387, P=0.013), low preoperative MD absolute value (OR=1.277, 95%CI: 1.205-1.355, P<0.001), small volume of tumor (OR=1.458, 95%CI: 1.060-4.289, P<0.001), low expression of VEGF in tumor tissue (OR=1.554, 95%CI: 1.089-2.457, P=0.022), and low expression of Ki-67 in tumor tissue (OR=1.552, 95%CI: 1.161-2.847, P=0.026).

CONCLUSION

After pituitary macroadenomas trans-sphenoidal resection, the independent influencing factors of the visual fields recovery were low preoperative MD absolute value, young age, small volume of tumor, and expression levels of VEGF/ Ki-67.

Vascular invasion in hepatitis B virus-related hepatocellular carcinoma with underlying cirrhosis: possible associations with ascites and hepatitis B viral factors?

Vascular invasion is one of the most important prognostic factors for patients with hepatocellular carcinoma (HCC). The objective of the current, retrospective study was to determine the associations of ascites and hepatitis B viral factors (HBeAg and anti-HBe status and HBV DNA levels), as well as tumor-related factors (size, tumor number, grade, and location) with micro- or macroscopic vascular invasion in patients with HCC that developed as a result of hepatitis B virus (HBV)-related cirrhosis. A total of 336 consecutive patients were included. Potential factors associated with micro- or macroscopic vascular invasion were analyzed by logistic regression. Ascites were more commonly detected in patients with micro- or macroscopic vascular invasion, and the presence of ascites was independently associated with vascular invasion. Among patients with mild-to-moderate or severe ascites, the odds ratio for macroscopic vascular invasion was 4.83 (95 % confidence interval [CI] 2.29-10.16) and 11.87 (95 % CI 4.53-31.07), respectively. Similarly, the presence of ascites was associated with microscopic vascular invasion (OR 5.00; 95 % CI 1.23-20.31). In contrast, hepatitis B viral factors were not significantly associated with vascular invasion. The presence of ascites was associated with vascular invasion in patients with HBV-related cirrhotic HCC. Thus, patients with ascites, vascular invasion should be considered and more frequent surveillance should be performed after curative treatment.

Expression and clinical significance of vascular endothelial growth factor and fms-related tyrosine kinase 1 in colorectal cancer

The aim of the present study was to investigate the prognostic value of vascular endothelial growth factor (VEGF) and its receptor, fms-related tyrosine kinase-1 (FLT-1), in patients with colorectal cancer. An immunohistochemical approach was used to detect the protein expression of VEGF and FLT-1 in 90 patients with colorectal cancer. The impact of VEGF and FLT-1 tumor cell expression, in addition to other factors, on overall survival (OS) was retrospectively assessed in 90 patients. Multivariate analysis was performed in order to determine the prognostic significance of the factors. The positive expression rate of VEGF in the colorectal cancer tissues was 62.2% (56/90). The positive expression rate of FLT-1 in colorectal cancer tissues was 48.9% (44/90). The results of the log-rank test revealed that improved OS rates were significantly associated with the absence of VEGF expression (P<0.0001). By contrast, FLT-1 expression had no significant impact on OS (P=0.289). Upon multivariate analysis, VEGF expression (P=0.038) and clinical stage (P=0.021) maintained significance. VEGF expression proved to be an independent negative predictor of OS in patients with colorectal cancer. Conversely, FLT-1 expression demonstrated no impact on OS.

New ways to successfully target tumor vasculature in ovarian cancer

PURPOSE OF REVIEW

The aim of this article was to review the recent literature on potential therapeutic strategies for overcoming resistance to antivascular endothelial growth factor drugs in ovarian cancer.

RECENT FINDINGS

Although clinical benefits of antivascular endothelial growth factor therapy were observed in ovarian cancer treatment trials, this use yielded only modest improvement in progression-free survival and, with the exception of cediranib, no effect on overall survival. Adaptive resistance and escape from antiangiogenesis therapy is likely a multifactorial process, including induction of hypoxia, vascular modulators, and immune response. New drugs targeting the tumor vasculature or other components of the surrounding microenvironment have shown promising results.

SUMMARY

When to start and end antiangiogenesis therapy and the choice of optimal treatment combinations remain controversial. Further evaluation of personalized novel angiogenesis-based therapy is warranted. Defining the critical interaction of these agents and pathways and the appropriate predictive markers will become an increasingly important objective for effective treatment.