Sunitinib treatment reduces tumor growth and limits changes in microvascular properties after minor surgical intervention in an in vivo model of secondary breast cancer growth in bone

Targeted combined therapy in 2D and 3D cultured MCF-7 cells using metformin and erlotinib-loaded mesoporous silica magnetic nanoparticles

AIM

This research aims to develop potential therapeutic nanostructures (NSs) encapsulating metformin (MET) and erlotinib (ER) for combinational therapy in breast cancer.

METHODS

The ER and MET, both were loaded on mesoporous silica magnetic nanoparticles conjugated with polyethylene glycol and methotrexate to achieve targeted NSs. The developed NSs were characterised using SEM, DLS, and FTIR. Afterward, MTT, Trypan blue, and DNA extraction assays were operated for biological evaluations in the 2D and 3D MCF-7 cells.

RESULTS

Physicochemical approaches indicated the mean diameter of 69.4 nm ± 9.5 (PDI = 0.64), and neutral charge (2 mv) for the developed NSs. MET and ER-loaded NSs exhibited 62.56% ± 4.41 and 67.73% ± 3.03 drug release amount in pH = 5.4, respectively. MTT assay revealed that ER- and MET-loaded NSs had less metabolic activity (≈ 20%) in comparison with non-targeted NSs.

CONCLUSION

Overall, our combined ER and MET-loaded targeted NSs result in a synergistic inhibitory impact on MCF-7 cells.

Current advances in the diagnosis and personalized treatment of breast cancer: lessons from tumor biology

Breast cancer treatment has advanced enormously in the last decade. Most of this is due to advances reached in the knowledge regarding tumor biology, mainly in the field of diagnosis and treatment. This review brings information about how the genomics-based information contributed to advances in breast cancer diagnosis and prognosis perspective, as well as presents how tumor biology discoveries fostered the main therapeutic approaches available to treat such patients, based on a personalized point of view.

Minimally Invasive Surgery without Decompression for Hepatocellular Carcinoma Spinal Metastasis with Epidural Spinal Cord Compression Grade 2

Objective

There is a lack of knowledge regarding whether decompression is necessary in treating patients with epidural spinal cord compression (ESCC) grade 2. The purpose of this study was to compare the outcomes of minimally invasive surgery (MIS) without decompression and conventional open surgery (palliative laminectomy) for patients with hepatocellular carcinoma (HCC) spinal metastasis of ESCC grade 2.

Methods

Patients with HCC spinal metastasis requiring surgery were retrospectively reviewed. Patients with ESCC grade 2, medically intractable mechanical back pain, a Nurick grade better than 3, 3–6 months of life expectancy, Tomita score ≥5, and Spinal Instability Neoplastic Score ≥7 were included. Patients with neurological deficits, other systemic illnesses and less than 1 month of life expectancy were excluded. Thirty patients were included in the study, including 17 in the open surgery group (until 2008) and 13 in the MIS group (since 2009).

Results

The MIS group had a significantly shorter operative time (94.2±48.2 minutes vs. 162.9±52.3 minutes, p=0.001), less blood loss (140.0±182.9 mL vs. 1534.4±1484.2 mL, p=0.002), and less post-operative intensive care unit transfer (one patient vs. eight patients, p=0.042) than the open surgery group. The visual analogue scale for back pain at 3 months post-operation was significantly improved in the MIS group than in the open surgery group (3.0±1.2 vs. 4.3±1.2, p=0.042). The MIS group had longer ambulation time (183±33 days vs. 166±36 days) and survival time (216±38 days vs. 204±43 days) than the open surgery group without significant difference (p=0.814 and 0.959, respectively).

Conclusion

MIS without decompression would be a good choice for patients with HCC spinal metastasis of ESCC grade 2, especially those with limited prognosis, mechanical instability and no neurologic deficit.

Acquired tumor resistance to antiangiogenic therapy: Mechanisms at a glance

Angiogenesis is critical for oxygen and nutrient delivery to proliferating tumor cells. Therefore, as angiogenesis is required and vital for the tumor growth and metastasis. Antiangiogenic therapy is considered to be beneficial for tumor growth prevention due to starvation of tumor of oxygen and nutrients, but in some cases, the benefits are not permanent. Tyrosine kinase inhibitors and many other agents often target angiogenesis through inhibition of the vascular endothelial growth factor (VEGF) pathway. Although preclinical studies showed satisfactory outcomes in tumor growth inhibition, antiangiogenic therapy in the clinical setting may not be effective. The resistance observed in several tumor types through alternative angiogenic “escape” pathways contributes to restoration of tumor growth and may induce progression, enhancement of invasion, and metastasis. Therefore, activation of major compensatory angiogenic pathways, sustaining tumor angiogenesis during VEGF blockade contributing to the recurrence of tumor growth overcome antiangiogenic strategies. In this review, we summarize the novel mechanisms involved in evasive resistance to antiangiogenic therapies and represent different cancer types which have the ability to adapt to VEGF inhibition achieving resistance to antiangiogenic therapy through these adaptive mechanisms.

In vivo functional and morphological characterization of bone and striated muscle microcirculation in NSG mice

Organ-specific microcirculation plays a central role in tumor growth, tumor cell homing, tissue engineering, and wound healing. Mouse models are widely used to study these processes; however, these mouse strains often possess unique microhemodynamic parameters, making it difficult to directly compare experiments. The full functional characterization of bone and striated muscle microcirculatory parameters in non-obese diabetic-severe combined immunodeficiency/y-chain; NOD-Prkds IL2rg (NSG) mice has not yet been reported. Here, we established either a dorsal skinfold chamber or femur window in NSG mice (n = 23), allowing direct analysis of microcirculatory parameters in vivo by intravital fluorescence microscopy at 7, 14, 21, and 28 days after chamber preparation. Organ-specific differences were observed. Bone had a significantly lower vessel density but a higher vessel diameter than striated muscle. Bone also showed higher effective vascular permeability than striated muscle. The centerline velocity values were similar in the femur window and dorsal skinfold chamber, with a higher volumetric blood flow in bone. Interestingly, bone and striated muscle showed similar tissue perfusion rates. Knowledge of physiological microhemodynamic values of bone and striated muscle in NSG mice makes it possible to analyze pathophysiological processes at these anatomic sites, such as tumor growth, tumor metastasis, and tumor microcirculation, as well as the response to therapeutic agents.

Comparison Between Minimally Invasive Surgery and Conventional Open Surgery for Patients With Spinal Metastasis: A Prospective Propensity Score-Matched Study

STUDY DESIGN

Prospective propensity score-matched study.

OBJECTIVE

To compare the outcomes of minimal invasive surgery (MIS) and conventional open surgery for spinal metastasis patients.

SUMMARY OF BACKGROUND DATA

There is lack of knowledge on whether MIS is comparable to conventional open surgery in treating spinal metastasis.

METHODS

Patients with spinal metastasis requiring surgery from January 2008 to December 2010 in two spine centers were recruited. The demographic, preoperative, operative, perioperative and postoperative data were collected and analyzed. Thirty MIS patients were matched with 30 open surgery patients using propensity score matching technique with a match tolerance of 0.02 based on the covariate age, tumor type, Tokuhashi score, and Tomita score.

RESULTS

Both groups had significant improvements in Eastern Cooperative Oncology Group (ECOG), Karnofsky scores, visual analogue scale (VAS) for pain and neurological status postoperatively. However, the difference comparing the MIS and open surgery group was not statistically significant. MIS group had significantly longer instrumented segments (5.5 ± 3.1) compared with open group (3.8 ± 1.7). Open group had significantly longer decompressed segment (1.8 ± 0.8) than MIS group (1.0 ± 1.0). Open group had significantly more blood loss (2062.1 ± 1148.0 mL) compared with MIS group (1156.0 ± 572.3 mL). More patients in the open group (76.7%) needed blood transfusions (with higher average units of blood transfused) compared with MIS group (40.0%). Fluoroscopy time was significantly longer in MIS group (116.1 ± 63.3 s) compared with open group (69.9 ± 42.6 s). Open group required longer hospitalization (21.1 ± 10.8 days) compared with MIS group (11.0 ± 5.0 days).

CONCLUSION

This study demonstrated that MIS resulted in comparable outcome to open surgery for patients with spinal metastasis but has the advantage of less blood loss, blood transfusions, and shorter hospital stay.

LEVEL OF EVIDENCE

3.

Cellular effects induced by 17-β-estradiol to reduce the survival of renal cell carcinoma cells

Background

Renal cell carcinoma (RCC) is an adult malignancy with 2:1 men-to-women ratio, which implies the possible role of sex hormones in RCC carcinogenesis. One of the predominant sex hormones in women before menopause, 17-β-estradiol (or E2), may regulate RCC growth by cellular mechanisms that are still not fully understood.

Methods

The expression levels of E2 receptors (ER1 and ER2) were determined in different RCC cell lines. The DNA damage response induced by E2 was determined by a DNA double-strand break marker γH2AX. To study the possible effect of E2 on oxidative stress response, RCC cells were stained with 2,7-dichlorofluorescein diacetate and analyzed by flow cytometry. Upregulation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) ser40 phosphorylation in response to oxidative stress was detected by immunoblotting. Finally, annexin V/propidium iodide (PI) double staining assay was used to determine E2-induced cellular apoptosis.

Results

Variable expression of ER1 and ER2 were found in the RCC cell lines studied (786-O, A498, and ACHN), in which ACHN and A498 showed highest and lowest ER expression, respectively. In A498 cells, E2 induced DNA double-strand breaks with positive staining of γH2AX. On the other hand, the level of reactive oxidative species were elevated in ACHN cells after E2 treatment. The E2-induced oxidative stress also induced the Ser40 phosphorylation and nuclear translocation of Nrf2. Finally, we also demonstrated that E2 induced apoptosis as revealed by annexin V/PI double staining.

Conclusions

In this study, we demonstrated the cellular effects of E2 on DNA repair, ROS production as well as Nrf2 activation, and apoptosis in RCC cell lines. Together these cellular alterations may contribute to the reduced viability of RCC cells following E2 treatment.