Prognostic and predictive value of vascular endothelial growth factor and its soluble receptors, VEGFR-1 and VEGFR-2 levels in the sera of small cell lung cancer patients

Interaction of Some Amino-Nitrile Derivatives with Vascular Endothelial Growth Factor Receptor 1 (VEGFR1) Using a Theoretical Model

BACKGROUND

Some studies indicate that the angiogenesis process is related to vascular endothelial growth factor, which can interact with endothelial cell surface receptors (VEGF-R1, VEGF-R2, and VEGF-R3); this biochemical process and other factors result in the promotion and growth of new blood vessels under normal conditions. However, some studies indicate that this phenomenon could also occur in cancer cells. It is important to mention that some amino derivatives have been prepared as VEGF-R1 inhibitors; however, their interaction with VEGF-R1 is not clear, perhaps due to different experimental approaches or differences in their chemical structure.

OBJECTIVE

The aim of this study was to evaluate the theoretical interaction of several amino-nitrile derivatives (Compounds 1 to 38) with VEGF-R1.

METHODS

The theoretical interaction of amino-nitrile derivatives with VEGF-R1 was carried out using the 3hng protein as the theoretical model. In addition, cabozantinib, pazopanib, regorafenib, and sorafenib were used as controls in the DockingServer program.

RESULTS

The results showed different amino acid residues involved in the interaction of amino-nitrile derivatives with the 3hng protein surface compared with the controls. In addition, the inhibition constant (Ki) was lower for Compounds 10 and 34 than for cabozantinib. Other results show that Ki for Compounds 9, 10, 14, 27-29 and 34-36 was lower in comparison with pazopanib, regorafenib, and sorafenib.

CONCLUSIONS

All theoretical data suggest that amino-nitrile derivatives could produce changes in the growth of some cancer cell lines through VEGFR-1 inhibition. Therefore, these amino-nitrile derivatives could be a therapeutic alternative to treat some types of cancer.

Efficacy and safety of antiangiogenic agents or chemotherapy plus EGFR-TKIs in advanced non-small cell lung cancer: A systematic review and network meta-analysis

BACKGROUND

The combination of antiangiogenic agents with epidermal growth factor receptor inhibitors (EGFR-TKIs) and chemotherapy with EGFR-TKIs are the most common combination treatment options in epidermal growth factor receptor (EGFR) positive non-small cell lung cancer (NSCLC). This network meta-analysis was performed to evaluate the differences between them.

METHODS

We searched the PubMed, EMBASE and the Cochrane Controlled Trials Register up to August 2022. The primary outcomes were progression-free survival (PFS) and objective response rate (ORR). The secondary endpoints were overall survival (OS), disease control rate (DCR) and adverse events (AEs). The data of hazard ratio (HR) or risk ratio (RR) with their corresponding 95% confidence intervals (CIs) were extracted in the studies. A network meta-analysis (NMA) was used to indirectly compare the efficacy and safety of antiangiogenic agents plus EGFR-TKIs and chemotherapy plus EGFR-TKIs.

RESULTS

Pooled data of included studies were demonstrated that chemotherapy plus EGFR-TKIs had a benefit in ORR compared to antiangiogenic agents plus EGFR-TKIs in patients with EGFR mutated NSCLC (RR = 1.1, 95% CI: 1.0-1.2). However, there were no significant differences in PFS, OS and DCR between in the two group (PFS: HR = 1.0, 95% CI: 0.74-1.6; OS: HR = 0.78, 95% CI: 0.45-1.5; DCR: RR = 1.0, 95% CI: 0.94-1.1). The common treatment-related AEs in the two groups were relatively manageable.

CONCLUSION

Based on the efficacy and safety, the combination of chemotherapy with EGFR-TKIs is considered the best combination treatment options in advanced NSCLC with EGFR mutation.

Comprehensive Characterization of the Genomic Landscape in Chinese Pulmonary Neuroendocrine Tumors Reveals Prognostic and Therapeutic Markers (CSWOG-1901)

BACKGROUND

Pulmonary neuroendocrine tumors (pNETs) include typical carcinoid (TC), atypical carcinoid (AC), large cell neuroendocrine carcinoma (LCNEC), and small cell lung carcinoma (SCLC). The optimal treatment strategy for each subtype remains elusive, partly due to the lack of comprehensive understanding of their molecular features. We aimed to explore differential genomic signatures in pNET subtypes and identify potential prognostic and therapeutic biomarkers.

METHODS

We investigated genomic profiles of 57 LCNECs, 49 SCLCs, 18 TCs, and 24 ACs by sequencing tumor tissues with a 520-gene panel and explored the associations between genomic features and prognosis.

RESULTS

Both LCNEC and SCLC displayed higher mutation rates for TP53, PRKDC, SPTA1, NOTCH1, NOTCH2, and PTPRD than TC and AC. Small cell lung carcinoma harbored more frequent co-alterations in TP53-RB1, alterations in PIK3CA and SOX2, and mutations in HIF-1, VEGF and Notch pathways. Large cell neuroendocrine carcinoma (12.7 mutations/Mb) and SCLC (11.9 mutations/Mb) showed higher tumor mutational burdens than TC (2.4 mutations/Mb) and AC (7.1 mutations/Mb). 26.3% of LCNECs and 20.8% of ACs harbored alterations in classical non-small cell lung cancer driver genes. The presence of alterations in the homologous recombination pathway predicted longer progression-free survival in advanced LCNEC patients with systemic therapy (P = .005) and longer overall survival (OS) in SCLC patients with resection (P = .011). The presence of alterations in VEGF (P = .048) and estrogen (P = .018) signaling pathways both correlated with better OS in patients with resected SCLC.

CONCLUSION

We performed a comprehensive genomic investigation on 4 pNET subtypes in the Chinese population. Our data revealed distinctive genomic signatures in subtypes and provided new insights into the prognostic and therapeutic stratification of pNETs.

Immunohistochemical expression of VEGFR1 in non small cell lung carcinomas: Lower VEGFR1 expression is asociated with squamous cell carcinoma subtype and high SUV max values in 18F-FDG PET

BACKGROUND

To study the possible relation between immunohistochemical expression of vascular endothelial growth factor receptor 1 (VEGFR1) and the maximum standardised uptake value (SUV max) of ¹⁸F-FDG PET in patients with non small cell lung cancer (NSCLC).

MATERIAL AND METHODS

The study included 39 patients with NSCLC (24 squamous cell carcinomas and 15 adenocarcinomas). According to the clinical stage, the patients were distributed as follows: 8 stage I, 7 stage II, 15 stage III and 9 stage IV. Immunohistochemical expression of VEGFR1 was studied through the technique of tissue-matrix using Tissue Arrayer Device (Beecher Instruments, Sun Prairie, WI), using the polyclonal antibody against VEGFR1 (Santa Cruz Biotechnology, California, USA).

RESULTS

Positive VEGFR1 immunohistochemical expression was noted in 23 cases (59%). The number of positive tumours was not related with clinical stage but there was a different statistically significant association (p:0,0009) between VEGFR1 positivity and histological type, corresponding the greater percentages of positive results to adenocarcinomas (93,3%) versus in squamous cell carcinomas (37,5%). Likewise, SUV max values were higher (p: 0,039) in negative VEGFR1 carcinomas than in positive VEGFR1 tumors (r: 4-32,1; 16,4+/-6,4 (median 16,1) vs r: 3-47; 14,5+/-8,6 (12,8)).

CONCLUSIONS

Our results led us to consider that in NSCLC, the negative VEGFR1 immunohistochemical expression is associated significantly with squamous cell carcinomas subtype and with higher SUV max values in ¹⁸F-FDG-PET.

Angiogenesis Inhibitors in Small Cell Lung Cancer

Inhibition of angiogenesis has been demonstrated to be an efficacious strategy in treating several tumors. Vascular endothelial growth factor (VEGF) is the most important protein with proangiogenic functions and it is overexpressed in small cell lung cancer (SCLC). Bevacizumab, a monoclonal antibody directed against VEGF, showed a promising activity in combination with etoposide and cisplatin as first-line treatment of patients with extended stage (ES)-SCLC and two randomized studies confirmed that bevacizumab improved PFS, but failed to prolong OS. Instead, disappointing results have been observed with endostar, sunitinib, sorafenib, vandetanib, and thalidomide in combination with chemotherapy in the first-line setting, with sunitinib in the maintenance setting, with sunitinib, cediranib and nintedanib as single agents or ziv-aflibercept in combination with topotecan in second-line setting. Only anlotinib improved OS and PFS as third-line therapy in Chinese patients with SCLC, and it was approved with this indication in China. Future challenges are the evaluation of the role of angiogenesis inhibitors in combination with immune- checkpoint inhibitors and chemotherapy in SCLC patients and the identification of predictive biomarkers of response to both agents.

Immunohistochemical expression of VEGFR1 in non small cell lung carcinomas: Lower VEGFR1 expression is asociated with squamous cell carcinoma subtype and high max SUV values in 18F-FDG PET

BACKGROUND

To study the possible relation between immunohistochemical expression of vascular endothelial growth factor receptor 1 (VEGFR1) and the maximum standardised uptake value (maxSUV) of 18F-FDG PET in patients with non small cell lung cancer.

MATERIAL AND METHODS

The study included 39 patients with NSCLC (24 squamous cell carcinomas and 15 adenocarcinomas). According to the clinical stage, the patients were distributed as follows: 8 stage I, 7 stage II, 15 stage III and 9 stage IV. Immunohistochemical expression of VEGFR1 was studied through the technique of tissue-matrix using tissue arrayer device (Beecher Instruments, Sun Prairie, WI), using the polyclonal antibody against VEGFR1 (Santa Cruz Biotechnology, California, USA).

RESULTS

Positive VEGFR1 immunohistochemical expression was noted in 23 cases (59%). The number of positive tumours was not related with clinical stage but there was a different statistically significant association (p:.0009) between VEGFR1 positivity and histological type, corresponding the greater percentages of positive results to adenocarcinomas (93.3%) versus in squamous cell carcinomas (37.5%). Likewise, maxSUV values were higher (p: .039) in negative VEGFR1 carcinomas than in positive VEGFR1 tumors (r: 4-32.1; 16.4+/-6.4 [median 16.1] vs. r: 3-47; 14.5+/-8.6 [12.8]).

CONCLUSIONS

Our results led us to consider that in NSCLC, the negative VEGFR1 immunohistochemical expression is associated significantly with squamous cell carcinomas subtype and with higher maxSUV values in 18F-FDG-PET.

Evaluation of diagnostic and predictive values of the serum VEGF-A level and systemic immune-inflammation index in small cell lung cancer

Purpose: To evaluate diagnostic and predictive values of the serum vascular endothelial growth factor-A (VEGF-A) level and systemic immune-inflammation index (SII) in small cell lung cancer (SCLC) patients.

Methods: From January 2018 to April 2020, we prospectively enrolled 59 untreated SCLC patients in the study group and 50 non-neoplastic patients in the control group. Blood samples were collected at baseline, after the first two cycles of chemotherapy and at progression in the study group and at entry in the control group. Serum VEGF-A was measured by chemiluminescence, SII was calculated based on complete blood count results, and the relationship between the VEGF-A/SII and clinicopathological characteristics, chemotherapeutic efficacy and progression-free survival (PFS) of SCLC patients was analyzed.

Results: Baseline serum VEGF-A was significantly higher in SCLC patients than in non-neoplastic patients (P<0.001), while baseline SII was not (P=0.114). There was no correlation between baseline VEGF-A and SII in SCLC patients (P=0.123); however, there was a significant correlation between baseline VEGF-A and disease stage and central nervous system (CNS) metastasis (P=0.021 and P=0.012, respectively), as well as between baseline SII and disease stage and liver metastasis (P=0.026 and P=0.018, respectively). Serum VEGF-A was significantly lower than the pretreatment level after 2 cycles of treatment (P=0.049) but was not different at progression (P=0.247). Baseline VEGF-A was correlated with the treatment response of first-line chemotherapy (P=0.001), while baseline SII was not (P=0.392). Kaplan-Meier survival analysis suggested that the PFS of first-line chemotherapy was significantly longer in the low-VEGF-A group at baseline than the high-VEGF-A group (11.37 vs. 6.17 months, P<0.001). There was a trend toward longer PFS of first-line chemotherapy in the low-SII group at baseline than the high-SII group, but the difference was not significant (12.10 vs. 9.10 months, P>0.050). Univariate and multivariate Cox regression analyses suggested that baseline VEGF-A (HR: 3.443, 95% CI: 1.330-8.908, P=0.011) was an independent prognostic factor for PFS in SCLC patients.

Conclusions: Baseline serum VEGF-A and SII are associated with important clinicopathological characteristics of SCLC patients. VEGF-A, but not SII, has the ability of diagnosis and predicting first-line chemotherapeutic efficacy and prognosis in SCLC patients.

Knockdown of neuron-specific enolase suppresses the proliferation and migration of NCI-H209 cells

Neuron-specific enolase (NSE) is generally considered as a marker for diagnosis and evaluation of the response to therapy in small cell lung cancer (SCLC). However, the role of NSE in the progression of SCLC remains to be elucidated. In the present study, the functions of NSE in SCLC, in addition to the potential mechanisms, were investigated using a loss-of-function approach with NSE-targeting small interfering (si)RNA. The knockdown of NSE markedly decreased the proliferation of NCI-H209 cells, as indicated by MTT assay (P<0.05). Furthermore, the silencing of NSE resulted in the formation of smaller and fewer colonies compared with that in the control group (P<0.001). Flow cytometric analysis indicated that the silencing of NSE resulted in a decreased S-phase population among NCI-H209 cells (P<0.05). Transwell assay demonstrated that the silencing of NSE suppressed the migration of NCI-H209 cells (P<0.001). NCI-H209 cells transfected with NSE siRNA-1 or negative control were collected and the protein levels of metastasis-associated genes were detected using western blot analysis. The results indicated that the knockdown of NSE led to downregulation of the pro-metastatic gene vascular endothelial growth factor (VEGF; P<0.05) and the upregulation of metastasis suppressor genes NM23 and E-cadherin (P<0.05). Taken together, the results of the present study demonstrated that the silencing of NSE suppressed the migration, proliferation and colony formation ability of SCLC cells and decreased the S-phase population. In addition, the knockdown of NSE resulted in the upregulation of E-cadherin and NM23 and the downregulation of VEGF. Collectively, these results indicated that intracellular NSE may have an important role in the progression of SCLC.

Evaluation of factors associated with platinum-sensitivity status and survival in limited-stage small cell lung cancer patients treated with chemoradiotherapy

In this retrospective study, we analyzed the association of clinicopathological factors and therapeutic plans with platinum-sensitivity status and survival of limited-stage small cell lung cancer (LS-SCLC) patients. We enrolled 452 LS-SCLC patients with 279 platinum sensitive and 173 platinum refractory patients. The low serum neuro-specific enolase levels (NSE; p = 0.011), neutrophil-to-lymphocyte ratios (NLR; p = 0.013) and higher objective response rates (p = 0.003) were associated with sensitive group but not the refractory group. Multivariate analysis showed that treatment modality (HR = 0.267, p < 0.001), serum lactate dehydrogenase (LDH; HR = 1.894, p = 0.016), NLR (HR = 2.043, p = 0.043) and platinum-sensitivity status (HR = 0.561, p = 0.036) were independent prognostic factors for survival. We further showed that the numbers of chemotherapy cycles and response to first-line therapy were independent prognostic factors for refractory patients only. Our study demonstrates that platinum-sensitivity status is of prognostic importance, as it is strongly associated with survival in LS-SCLC patients.

Second-line pazopanib in patients with relapsed and refractory small-cell lung cancer: a multicentre phase II study of the Hellenic Oncology Research Group

Background:

Pazopanib is a tyrosine kinase inhibitor with antiangiogenic activity. Vascular endothelial growth factor expression is increased in SCLC and is correlated with poor prognosis. The efficacy and tolerance of second-line pazopanib in SCLC was evaluated.

Patients and methods:

Patients with platinum-sensitive (cohort A; n=39) and -resistant/refractory (cohort B; n=19) SCLC were enrolled in a multicentre phase II study. The primary end point was the progression-free survival rate (PFS-R) at week 8 in each cohort. Pazopanib (800 mg per day per os) was administered until progressive disease (PD). Circulating tumour cells (CTCs) were enumerated using the Cellsearch assay.

Results:

All patients were evaluable for response and toxicity. In the intention-to-treat analysis, eight (13.8%) patients achieved partial response (PR) (95% confidence interval (CI): 5.0–22.7), 20 (34.5%) stable disease (SD) and 30 (51.7%) PD. Accrual in cohort B was halted because the hard-stop rule was met; in cohort A, the PFS-R was 59% (95% CI: 43.5–74.4; PR=7, SD=16). Nine (23.1%) patients received pazopanib for >6 months and 3 of them for >12 months. One pazopanib cycle resulted to a significant decrease to the number of patients with ⩾5 CTCs/7.5 ml of blood (20%) compared with baseline (50%). The median PFS and OS for all patients was 2.5 months (95% CI: 1.9–3.1 months) and 6.0 months (95% CI: 3.8–8.2 months), respectively (cohort A: PFS=3.7 months and OS=8.0 months). No unexpected toxicity was observed.

Conclusions:

Second-line treatment with pazopanib in platinum-sensitive SCLC is well tolerated and resulted in promising objective responses and disease control; CTC enumeration might serve as a reliable surrogate biomarker of response.

Advances in antiangiogenic treatment of small-cell lung cancer

Small-cell lung cancer (SCLC), a poorly differentiated neuroendocrine malignancy, has a rapid growth rate, strong aggressiveness, early metastases, and poor prognosis. Angiogenesis greatly contributes to the metastatic process of SCLC, which has a higher vascularization compared with non-small-cell lung cancer (NSCLC). SCLC might constitute an ideal malignancy for assessing new antiangiogenic drugs and therapeutic strategies. Combining bevacizumab with paclitaxel has therapeutic benefits in chemoresistant, relapsed SCLC. The cisplatin–etoposide and bevacizumab combination, as the first-line treatment for extensive-stage SCLC, can improve progression-free survival (PFS), with an acceptable toxicity profile. Ziv-aflibercept combined with topotecan is promising for platinum-refractory SCLC. Chemotherapy combined with thalidomide cannot prolong survival. Maintenance sunitinib of 37.5 mg/day in extensive-stage SCLC patients following induction chemotherapy with platinum/etoposide improves median PFS by 1.6 months. Serum angiopoietin-2 concentrations and vascular endothelial growth factor levels correlate with poor prognosis. Bevacizumab, ziv-aflibercept, and sunitinib are worthy of further evaluation. Thalidomide, sorafenib, pomalidomide, and cediranib may not be suitable for SCLC.

Phase II study of bevacizumab plus irinotecan on the treatment of relapsed resistant small cell lung cancer

PURPOSE

This phase II study investigates the efficacy and safety of DNA topoisomerase I inhibitor irinotecan plus bevacizumab a monoclonal antibody against VEGF (BEVIRI) in patients with relapsed chemo-resistant SCLC.

METHODS

Patients who previously completed treatment with cisplatin-etoposide who relapsed within 3 months, had measurable extensive-stage SCLC, ECOG performance status 0-2 and adequate hematologic, renal and hepatic function, were given intravenous irinotecan 175 mg/m(2) plus intravenous bevacizumab 7.5 mg/kg on day 1 and 15 in 30 day cycles for a target of at least four cycles. No patients had received prophylactic intracranial irradiation. Treatment response was assessed with computer tomography scans with the completion of two consecutive cycles. Primary endpoint was overall response rate (ORR).

RESULTS

Thirty-two patients were enrolled and 28 of them were eligible for evaluation of response, toxicity and survival. The median age was 63.5 years (range 48-73). The ORR (CR and PR) was 25 % (95 % CI 8.9-41.0) and including patients with stable disease overall disease control rate at 2 months was 89 % (95 % CI 77.41-100). The median duration of response was 6 months, median progression-free survival was 3 months (mean PFS: 3.2, 95 % CI 2.7-3.7), and median overall survival was 6 months (mean OS: 6.3, 95 % CI 5.4-7.1). The PFS rate at 6 months was 3.6 %, and 1-year OS rate was 3.6 %. The median number of cycles received was 4.5 (range 1-6). There were two (7.1 %) hematologic (neutropenia) and one (3.5 %) non-hematologic (proteinuria) serious grades 3-4 adverse reactions without necessitating treatment discontinuation.

CONCLUSION

BEVIRI combination in relapsed chemo-resistant SCLC patients demonstrates promising efficacy and low toxicity compared to historical controls. Further investigation is warranted.

Lysosome-associated protein transmembrane-4β-35 is a novel independent prognostic factor in small cell lung cancer

The lysosome-associated protein transmembrane-4β-35 (LAPTM4B-35) protein has been indicated to be involved in solid tumors, while its role in small cell lung cancer (SCLC) remains unknown. The aim of this study is to investigate the LAPTM4B-35 protein expression and its clinical and prognostic role in SCLC patients. A total of 88 SCLC patients who underwent radical surgery between 2002 and 2010 were enrolled in the study. The level of messenger RNA (mRNA) and protein was detected from the fresh paired tumor specimens and adjacent normal tissues. The clinicopathological and survival data were collected. And the relationship between LAPTM4B-35 and clinicopathological features was analyzed. The prognostic value of LAPTM4B-35 for SCLC was investigated by univariate and multivariate analyses. The LAPTM4B-35 was overexpressed significantly in SCLC cancer tissues. The elevated protein expression was correlated strongly with clinical stage (p = 0.012) and tumor recurrence (p = 0.023). The 5-year overall survival and disease-free survival (DFS) were significantly worse in the patients with high LAPTM4B-35 level. Multivariate Cox analysis indicated that high LAPTM4B-35 expression was an independent prognostic factor for overall survival (OS) and DFS (p = 0.017 vs p = 0.011). LAPTM4B-35 overexpression was an independent factor in SCLC prognosis, which may be considered a potential useful marker in defining the SCLC prognosis.

Influence of pre-analytical variables on VEGF gene expression and circulating protein concentrations

BACKGROUND

The extended role of vascular endothelial growth factor (VEGF) in human pathophysiology led us to evaluate pre-analytical parameters possibly influencing its levels in peripheral blood and tissues. The effects on VEGF protein levels and mRNA expression were measured after storage delay (blood and tissue), use of different types of anticoagulants (blood), and after different numbers of freeze-thaw cycles (blood).

METHODS

Blood from healthy donors was sampled simultaneously in ethylene diamine tetraacetic acid (EDTA), acid citrate dextrose (ACD-A), hirudin, and serum separation tubes. For each anticoagulant, VEGF was measured by enzyme-linked immunosorbent assay (ELISA) with different conditions of delay at 4°C before centrifugation (2 h, 4 h, or 48 h) and of different numbers of freeze-thaw cycles (1, 2, and 10). The transcripts coding for the VEGF165 isoform were quantified in peripheral blood mononuclear cells by RT-PCR. Muscle biopsy samples were frozen with delays of 15, 30, or 60 min after surgery. VEGF expression was quantified on immunofluorescence stained slides.

RESULTS

The period of storage and the number of freeze-thaw cycles correlated with an increase in the levels of circulating VEGF (for each anticoagulant but not for serum) and its expression in PBMCs. VEGF expression measured from muscle biopsy sections was higher with freezing delays, with a peak at 30 and 60 min as compared to 15 min.

CONCLUSIONS

The most reliable conditions for measuring both circulating VEGF and its gene expression are to reduce time between blood collection and centrifugation, and to avoid multiple freeze-thaw cycles. Serum collection tubes with no additive and no separator were less sensitive to the pre-analytical variations analyzed in this study. Freezing delay had a significant influence on VEGF protein expression in tissue samples.

Relapsed small cell lung cancer: treatment options and latest developments

According to recent analyses, there was a modest yet significant improvement in median survival time and 5-year survival rate of limited stage small cell lung cancer (SCLC) in North America, Europe, Japan and other countries over the last 30 years. The median survival time of limited stage SCLC is 15-20 months and 5-year survival rate is 15% or less. In terms of extensive stage SCLC, a median survival time of 9.4-12.8 months and 2-year survival of 5.2-19.5% are still disappointing. Despite being highly sensitive to first-line chemotherapy and radiotherapy treatments, most patients with SCLC experience relapse within 2 years and die from systemic metastasis. While several clinical trials of cytotoxic chemotherapies and molecular targeting agents have been investigated in the treatment of relapsed SCLC, none showed a significant clinical activity to be able to exceed topotecan as second-line chemotherapy. There are problematic issues to address for relapsed SCLC, such as standardizing the treatment for third-line chemotherapy. Topotecan alone was the first approved therapy for second-line treatment for relapsed SCLC. Amrubicin is a promising drug and a variety of trials evaluating its efficacy have been carried out. Amrubicin has shown superiority to topotecan in a Japanese population, but was not superior in a study of western patients. There are some controversial issues for relapsed SCLC, such as treatment for older patients, third-line chemotherapy and efficacy of molecular targeting therapy. This article reviews current standard treatment, recent clinical trials and other topics on relapsed SCLC.

Soluble VEGFR1 concentration in the serum of patients with colorectal cancer

PURPOSE

VEGFR is involved in complex biological processes, including inflammation and cancer development, progression and metastasis. Many proteins, including VEGFR, are proteolytically released from the surface of cells by a process known as ectodomain shedding. The aim of this study was to assess the expression of soluble VEGFR1 (sVEGFR1) in the serum of patients with colorectal cancer (CRC).

METHODS

Sixty-two serum samples from healthy controls and 88 samples from patients with different stages of CRC were included in this study. The total protein concentration (TPC) was measured using a Bio-Rad protein assay, and the expression and concentration of sVEGFR1 was determined by a Western blot analysis and enzyme-linked immunosorbent assay, respectively.

RESULTS

No significant difference in the serum TPC of patients with and without CRC was seen. The relative s-VEGFR1 expression and concentration of sVEGFR1 in the serum of patients with CRC were significantly increased compared to those in controls (P < 0.001).

CONCLUSIONS

The results of this study suggest that VEGFR1 shedding may provide a reliable and practical indicator of the malignant potential, tumor progression and overall tumor burden. The findings also suggest that sVEGFR1 might be involved in the pathophysiology of CRC, and the detection of serum sVEGFR1 may be useful in classifying CRC.

CK-19 mRNA-positive cells in peripheral blood predict treatment efficacy and survival in small-cell lung cancer patients

Small-cell lung caner (SCLC) is the most aggressive form of lung cancer. The aim of this study was to investigate whether the presence of cytokeratin-19 (CK-19) mRNA-positive circulating tumor cells (CTCs) predicts treatment response, progression-free survival (PFS), and overall survival (OS) in SCLC patients who received standard therapy. Fifty-five SCLC patients were enrolled in this single-center prospective study. CK-19 mRNA-positive CTCs in blood samples were detected using real-time quantitative-PCR assay before the initiation of chemotherapy (B0) and after one chemotherapy cycle (B1) and three chemotherapy cycles (B3). The association with known prognostic factors and the effect of CK-19 mRNA-positive CTCs on patients' prognosis were analyzed. Patients with positivity for CK-19 mRNA-positive CTCs at B0, B1, and B3 time points had shorter PFS and OS compared with patients without (P = 0.014 and P = 0.01, respectively, at B0; P = 0.008 and P = 0.002, respectively, at B1; P = 0.003 and P = 0.001, respectively, at B3). Conversion of initial positivity for CK-19 mRNA-positive CTCs to negativity at B1 and B3 time points was associated with longer PFS and OS compared with patients with persistent positivity at three time points (P = 0.008 and P = 0.010, respectively). Multivariate analysis demonstrated that the presence of CK-19 mRNA-positive CTCs at B0, B1, and B3 time points remained strong predictors of PFS and OS after adjustment for clinically significant factors. In conclusion, detection of CK-19 mRNA-positive CTCs before and during chemotherapy is an accurate indication of subsequent disease progression and mortality for SCLC patients.

Effect of tumor microenvironment on tumor VEGF during anti-VEGF treatment: systems biology predictions

BACKGROUND

Vascular endothelial growth factor (VEGF) is known to be a potent promoter of angiogenesis under both physiological and pathological conditions. Given its role in regulating tumor vascularization, VEGF has been targeted in various cancer treatments, and anti-VEGF therapy has been used clinically for treatment of several types of cancer. Systems biology approaches, particularly computational models, provide insight into the complexity of tumor angiogenesis. These models complement experimental studies and aid in the development of effective therapies targeting angiogenesis.

METHODS

We developed an experiment-based, molecular-detailed compartment model of VEGF kinetics and transport to investigate the distribution of two major VEGF isoforms (VEGF121 and VEGF165) in the body. The model is applied to predict the dynamics of tumor VEGF and, importantly, to gain insight into how tumor VEGF responds to an intravenous injection of an anti-VEGF agent.

RESULTS

The model predicts that free VEGF in the tumor interstitium is seven to 13 times higher than plasma VEGF and is predominantly in the form of VEGF121 (>70%), predictions that are validated by experimental data. The model also predicts that tumor VEGF can increase or decrease with anti-VEGF treatment depending on tumor microenvironment, pointing to the importance of personalized medicine.

CONCLUSIONS

This computational study suggests that the rate of VEGF secretion by tumor cells may serve as a biomarker to predict the patient population that is likely to respond to anti-VEGF treatment. Thus, the model predictions have important clinical relevance and may aid clinicians and clinical researchers seeking interpretation of pharmacokinetic and pharmacodynamic observations and optimization of anti-VEGF therapies.

sVEGF R1 and Tie-2 levels during chemotherapy of lung cancer patients

Angiogenesis plays important role in tumor growth and development. Protein ligands and their receptor tyrosine kinases are crucial in tumor related angiogenesis. Ligand/receptor systems such as vascular endothelial growth factor (VEGF), and tyrosine kinase with immunoglobulin-like and epidermal growth factor homology domains (Tie) family play important role in this phenomenon. The aim of this study was to evaluate the concentration of soluble receptor of VEGF (sVEGF R1) and Tie-2 domain in plasma of lung cancer patients before and after chemotherapy. Forty four lung cancer patients, 11 with small lung cancer (SCLC), 5 females and 6 males (mean age 60.2, range 39-72 years), and 33 patients with non-small cell lung cancer (N-SCLC), 6 females and 27 males (mean age 61.9, range 42-78 years) received four courses of chemotherapy. Control group consisted of 44 patients with COPD, 4 females and 40 males (mean age 37.1, 18-60 years). In all cases clinical partial response was achieved. Both sVEGF R1 and Tie-2 concentrations were elevated in cancer group before treatment compared with control: sVEGF (pg/ml): 60.7 and 66.2 vs. 48.8 and Tie-2 (ng/ml): 37.3 and 37.5 vs. 30.7 in SCLC and N-SCLC vs. C, respectively. Treatment decreased sVEGF R1 (pg/ml): 66.7 vs. 11.6 (p < 0.05) and 66.2 vs. 14.39 (p < 0.001), and Tie-2 (ng/ml): 37.3 vs. 26.3 (p < 0.05) and 37.5 vs. 25.7 (p < 0.001) in SCLC and N-SCLC, respectively. We conclude that VEGF R1and Tie-2 receptors may play important role in lung cancer development and their receptor concentrations may reflect the patients' response to treatment.

A phase II study of sunitinib in patients with relapsed or refractory small cell lung cancer

PURPOSE

This study was conducted to evaluate the efficacy and safety of sunitinib in patients with relapsed or refractory small cell lung cancer (SCLC).

PATIENTS AND METHODS

Eligibility included histologic or cytologic diagnosis of SCLC, ECOG PS of 0-2, cancer progression following one or two prior chemotherapy or chemo-radiotherapy (CRT) and adequate organ functions. Treatment regimen consisted of a 6-week cycle of sunitinib given as 50mg p.o. daily for 4 weeks followed by 2 weeks off. The primary end point was objective response rate (ORR).

RESULTS

From March 2008 to October 2010, 25 patients were enrolled and 24 received treatment. The median age was 64.5 years; 22 patients (92%) were male. Eight patients (33%) displayed sensitive relapse. Seven patients (29%) received CRT and fifteen patients (63%) had received one prior chemotherapy. A median of 1 cycle (range 1-4) of sunitinib was administered, and 23 patients were evaluable for response. Two patients displayed partial response, and seven patients presented stable disease with a ORR of 9% (95% CI, 1-28%). The median progression-free (PFS) and overall survivals were 1.4 months (95% CI, 1.1-1.7) and 5.6 months (95% CI, 3.5-7.7), respectively. The common grade 3 or 4 toxicities included thrombocytopenia (63%), asthenia (29%) and neutropenia (25%).

CONCLUSIONS

Although tumor response was noted in 2 patients, the median PFS was short and most patients were unable to tolerate the treatment. At the current dose schedule, sunitinib does not appear to warrant further evaluation.

Cisplatin, irinotecan, and bevacizumab for untreated extensive-stage small-cell lung cancer: CALGB 30306, a phase II study

PURPOSE

The efficacy of cisplatin, irinotecan, and bevacizumab was evaluated in patients with extensive-stage small-cell lung cancer (ES-SCLC).

PATIENTS AND METHODS

Patients with ES-SCLC received cisplatin 30 mg/m(2) and irinotecan 65 mg/m(2) on days 1 and 8 plus bevacizumab 15 mg/kg on day 1 every 21 days for six cycles on this phase II study. The primary end point was to differentiate between 50% and 65% 12-month survival rates.

RESULTS

Seventy-two patients were enrolled between March 2005 and April 2006; four patients canceled, and four were ineligible. Grade 3 or 4 toxicities included neutropenia (25%), all electrolyte (23%), diarrhea (16%), thrombocytopenia (10%), fatigue (10%), nausea (10%), hypertension (9%), anemia (9%), infection (7%), vascular access thrombosis (2%), stroke (2%), and bowel perforation (1%). Three deaths (5%) occurred on therapy as a result of pneumonitis (n = 1), stroke (n =1), and heart failure (n = 1). Complete response, partial response, and stable disease occurred in three (5%), 45 (70%), and 11 patients (17%), respectively. Progressive disease occurred in one patient (2%). Overall response rate was 75%. Median progression-free survival (PFS) was 7.0 months (95% CI, 6.4 to 8.4 months). Median overall survival (OS) was 11.6 months (95% CI, 10.5 to 15.1 months). Hypertension ≥ grade 1 was associated with improved OS after adjusting for performance status (PS) and age (hazard ratio [HR], 0.55; 95% CI, 0.31 to 0.97; P = .04). Lower vascular endothelial growth factor levels correlated with worse PFS after adjusting for age and PS (HR, 0.90; 95% CI, 0.83 to 0.99; P = .03).

CONCLUSION

PFS and OS times were higher compared with US trials in ES-SCLC with the same chemotherapy. However, the primary end point of the trial was not met. Hypertension was associated with improved survival after adjusting for age and PS.

Opposing roles for HIF-1α and HIF-2α in the regulation of angiogenesis by mononuclear phagocytes

Macrophages contribute to tumor growth through the secretion of the proangiogenic molecule vascular endothelial growth factor (VEGF). We previously observed that monocytes treated with the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) produce a soluble form of the VEGF receptor-1 (sVEGFR-1), which neutralizes VEGF biologic activity. The VEGF and VEGFR-1 promoters both contain a hypoxia regulatory element, which binds the hypoxia-inducible factor (HIF) transcription factors under hypoxic conditions. Based on this observation, we examined VEGF and sVEGFR-1 production from monocytes cultured at various O(2) concentrations. The amount of sVEGFR-1 production observed from GM-CSF-treated monocytes increased with decreasing levels of O(2). This sVEGFR-1 was biologically active and sequestered VEGF. To evaluate the role of the HIFs in sVEGFR-1 production, we used macrophages with a genetic deletion of HIF-1α. HIF-1α(-/-) macrophages cultured with GM-CSF at hypoxia secreted diminished amounts of VEGF compared with HIF-1α(+/+) macrophages, whereas sVEGFR-1 secretion was unaffected. In contrast, siRNA-mediated knockdown of HIF-2α inhibited the production of sVEGFR-1 in response to GM-CSF and low O(2), whereas VEGF production was unaffected. These studies suggest that hypoxia, generally thought to promote angiogenesis, can induce antiangiogenic behavior from macrophages within a GM-CSF-rich environment. Furthermore, these results suggest specific and independent roles for HIF-1α and HIF-2α in hypoxic macrophages.

Correlations of RUNX3 and RASSF1A promoter hypermethylation with the progression and metastasis of gastric carcinoma

AIM: To investigate the clinical significance of runt-related transcription factor 3 (RUNX3) and Ras association domain family 1A (RASSF1A) promoter methylation in human gastric cancer.

METHODS: The mRNA expression and methylation of RUNX3, and RASSF1A in 62 gastric cancer specimens and 56 adjacent normal tissue specimens were detected by reverse transcription-polymerase chain reaction (RT-PCR) and methylation-specific PCR (MSP), respectively. The expression of VEGF protein was measured by immunohistochemistry in methylation-positive and -negative cancer tissue specimens and 20 normal gastric tissue specimens.

RESULTS: The mRNA expression levels of RUNX3 and RASSF1A in gastric cancer were lower than those in normal gastric tissue (0.629 ± 0.461 vs 0.893 ± 0.543 and 0.653 ± 0.476 vs 0.858 ± 0.581, respectively; both P < 0.05). The positive rates of RUNX3 and RASSF1A methylation were significantly higher in gastric cancer tissue specimens than in normal control ones (69.4% vs 26.8% and 66.1% vs 23.2%, respectively; both P < 0.01). The expression levels of RUNX3 and RASSF1A mRNAs were lower in methylation-positive cancer tissue specimens than in methylation-negative ones (P < 0.05). Neither RUNX3 nor RASSF1A promoter methylation were correlated with sex, age, tumor size, tumor differentiation degree, and Lauren classification. However, RASSF1A methylation was related with TNM stage and depth of infiltration, and RUNX3 methylation was associated with lymph node metastasis, vascular invasion and TNM stage. The positive rate of VEGF protein expression in RUNX3 methylation-positive gastric cancer specimens was significantly higher than that in RUNX3 methylation-negative ones (86.0% vs 57.9%, P < 0.05).

CONCLUSION: Aberrant RUNX3 and RASSF1A promoter methylation may lead to down-regulation of the two genes in GC and is therefore involved in the progression of the disease. RUNX3 promoter methylation may participate in the vascular/lymphatic metastasis of GC.

Association of plasma VEGF-A, soluble VEGFR-1 and VEGFR-2 levels and clinical response and survival in advanced colorectal cancer patients receiving bevacizumab with modified FOLFOX6

For individualized bevacizumab-based therapy, non-invasive biomarkers are necessary. This study assessed the predictive value of plasma vascular endothelial growth factor (VEGF)-A, soluble VEGF receptor (sVEGFR)-1 and sVEGFR-2 levels as biomarkers for clinical response and survival in advanced colorectal cancer (CRC) patients treated with bevacizumab and modified FOLFOX6 (mFOLFOX6). Forty-six unresectable advanced CRC patients and 20 healthy controls were included in this study. CRC patients were treated with bevacizumab and mFOLFOX6. Pretreatment plasma VEGF-A, sVEGFR-1 and sVEGFR-2 levels were measured using the multiplex immunoassay. Plasma VEGF-A, sVEGFR-1 and sVEGFR-2 levels were significantly higher in CRC patients than in the healthy subjects. The plasma sVEGFR-1 levels in the responder patients [complete response (CR)/partial response (PR)] and stable disease (SD) patients were significantly lower than those in the progressive disease (PD) patients (CR/PR vs. PD, p=0.025; SD vs. PD, p=0.032), while the plasma VEGF-A and sVEGFR-2 levels did not show any significant differences between the two groups of patients. Patients with higher sVEGFR-1 levels showed a significantly poorer progression-free survival (PFS) and overall survival (OS) than those with lower VEGFR-1 levels. In contrast, VEGF-A and sVEGFR-2 did not show any significant relationship between PFS and OS according to the status of each level. In the multivariate Cox proportional hazard regression analysis, sVEGFR-1 levels showed a significant relationship between PFS and OS. These results suggest that plasma sVEGFR-1 levels have a predictive value for clinical response and survival in advanced CRC patients treated with bevacizumab and mFOLFOX6. Larger scale studies are needed to further validate our results.

Venous thromboembolism in malignant gliomas

Malignant gliomas are associated with a very high risk of venous thromboembolism (VTE). While many clinical risk factors have previously been described in brain tumor patients, the risk of VTE associated with newer anti-angiogenic therapies such as bevacizumab in these patients remains unclear. When VTE occurs in this patient population, concern regarding the potential for intracranial hemorrhage complicates management decisions regarding anticoagulation, and these patients have a worse prognosis than their VTE-free counterparts. Risk stratification models identifying patients at high risk of developing VTE along with predictive plasma biomarkers may guide the selection of eligible patients for primary prevention with pharmacologic thromboprophylaxis. Recent studies exploring disordered coagulation, such as increased expression of tissue factor (TF), and tumorigenic molecular signaling may help to explain the increased risk of VTE in patients with malignant gliomas.

Efficacy of plasma vascular endothelial growth factor in monitoring first-line chemotherapy in patients with advanced non-small cell lung cancer

BACKGROUND

Along with the development of new cancer therapeutics, more effective tools for the estimation of response to therapy and prediction of disease progression are required for the better management of inoperable cancer patients.

METHODS

We studied 134 newly diagnosed and primarily untreated advanced non-small cell lung cancer patients and 100 controls. Forty two patients received platinum-based chemotherapy. Plasma VEGF levels were quantified in all samples at baseline and also before second and third chemotherapy cycle in 42 patients and correlated with response to therapy as assessed by computed tomography after the third chemotherapy cycle.

RESULTS

We observed that, patients who went into remission had significantly lower baseline VEGF levels before second and third cycles of chemotherapy when compared with patients with no change and progression. Plasma VEGF levels showed a greater decrease from cycle 1 to 2 and from cycle 1 to 3 in patients who showed remission in comparison to those with no change or progression. Plasma VEGF levels before the second cycle detected poor response to therapy with a sensitivity and specificity of 76.9% and 75.0%, respectively (area under the ROC curve = 0.724). Early prediction of disease progression was achieved with a sensitivity and specificity of 71.4% for plasma VEGF before cycle 2 (area under the ROC curve = 0.805). The kinetics of VEGF form cycle 1 to 2 and cycle 1 to 3 also gave significant information for predicting disease progression as well as insufficient therapy response.

CONCLUSION

Monitoring of plasma VEGF levels during the course of first-line chemotherapy could identify patients who are likely to have insufficient response to therapy and disease progression at an early stage. This may help in individualizing treatment and could lead to better management of the advanced stage lung cancer.

Hypoxia inducible factor-1 alpha and vascular endothelial growth factor in biopsies of small cell lung carcinoma

Neoangiogenesis has been documented in small cell lung carcinoma (SCLC). In addition, antiangiogenic therapies are being tested in clinical trials that involve SCLC. However, study of the underlying mechanisms has been performed almost exclusively in cell lines. In the current study, we immunostained 30 biopsy samples of SCLC with antibodies to hypoxia inducible factor-1 alpha (HIF-1 alpha), vascular endothelial growth factor (VEGF), vascular endothelial growth factor-receptor 1 (VEGF-R1/flt-1) and vascular endothelial growth factor-receptor 2 (VEGF-R1/flk-1). The immunoreactivity was analyzed using a bivariate Spearman correlation test and linear regression analysis. We found significant correlation between HIF-1 alpha nuclear staining and VEGF staining. Moreover HIF-1 alpha+/VEGF+ cases were associated with poor survival. We also found a positive correlation between VEGF and VEGF-R2 expression. We suggest that a HIF-1 alpha/VEGF angiogenic pathway may exist in vivo in SCLC, similar to that in non-SCLC. Our data also suggest a potential VEGF/VEGFR-2 autocrine pathway in SCLC. The inclusion of novel inhibitors to HIF-1 alpha and other factors may optimize antiangiogenic interventions in SCLC.