Cutaneous melanoma is the most serious form of skin cancer and is curable only if it is detected early. The most effective treatment for the melanoma is surgical excision of the lesion. Traditionally, wide margins of excision have been used for effective treatment, but are not always desirable due to increased risk of infection and esthetic reasons. Besides, safe surgical margins of the lesion are not always correlated well with the size of the lesions. We have previously developed a system using elastic light single-scattering spectroscopy to differentiate cancerous tissue from non-cancerous tissue and tested it in vitro. The goal of this study was, therefore, to determine the effectiveness of this system ex vivo by using a mouse model of melanoma. First, a melanoma cell line; B16F10 were injected subcutaneously at right mid flank region of C57BL6 mice (n=5) and allowed to develop for two weeks. Tumors were dissected and spectra were taken on tumor tissue and on normal looking skin tissue that was 10 mm distant from the incision. Since these tumors become markedly necrotic in the middle, spectra of necrotic area was also taken. Slopes of the spectra were positive taken on non-cancerous skin tissues that were later verified by histological examination. On the other hand, it gave negative slopes on melanomas. Increased sizes of the nuclei correlated with the negative slope while smaller nuclei found in non-cancerous tissue gave positive slope. Spectrum taken from necrotic area differed from both cancerous and non-cancerous tissue such that it gave a U-shaped spectrum. These results demonstrate that elastic light single-scattering spectroscopy system can differentiate cancerous tissue from non-cancerous and has potential to be used intraoperatively to determine the surgical margins.
INTRODUCTION: Although, the use of free flap in reconstructive surgery has increased over time,1 the complications related to obstructed venous outflow are common in flap transfer and can result in irreversible tissue injury, necrosis, and flap loss.2 Microneedling aims to induce as many microwounds in the dermis by the needle pricks as possible rolling needles vertically, horizontally and diagonally with pressure over the treated area.3 Microneedling initiate the normal phases of wound healing. makes it release of many growth factors and cytokines.4 Platelet rich plasma (PRP) is a rich source of growth factors, has been found effective in accelerating significant tissue repair and regeneration, and releases massive quantities of platelet growth factors.4 The purpose of our study is to determine the efficiency of microneedling and PRP enriched microneedling method for alleviating the harmful effect of venous congestion. MATERIALS AND METHODS: Ten adult male Wistar rats were used to obtain platelet rich plasma. A bilateral an epigastric skin flap based on the superficial epigastric artery and vein were harvested. The animals were randomized into five groups (n=8 each group): sham, control, microneedling (M), PRP applied microneedling (M+PRP), platelet poor plasma (PPP) applied microneedling group (M+PPP). Four hours of complete ischemia was induced (except in sham group) and after the end of ischemia, treatments were applied. Flap necrosis, neuronal and non-neuronal levels of Substance P as well as histological changes in the tissues were evaluated at the seventh postoperative day. RESULTS: Surviving flap area of M+PRPgroup was significantly higher (p<0,01) than all the other groups. Microneeding alone increased the survival of the flap area when compared to the control group (Table 1). In M+PRP group, all epidermal layers were clearly organized and dermal integrity was similar to sham dermiş (figure 1). We also observed that microneeding alone markedly decreased Substance P levels (p=0,001)demonstrating activation of sensory nerve fibers. which might br involved in healing process.Table 1: Extent of necrosis following treatments. M-microneedling; PRP: Platelet rich plasma, PPP: Platelet poor plasma.Figure 1: Histologic analysis with haematoxylin-eosin (H+E). In M+PRP groip, all epidermal layers were clearly organized and the junction between epidermis and dermis was shown in obviously. Neoangiogenesis was seen in dermal layer (arrows). And inflammatory cells were realized in endovascular area of dermal and hypodermal layers (arrowhead). Also, connective tissue was more organized compare than the other groups of epidermal and dermal area (double arrowheads figure L,M).CONCLUSION: M+PRP might be an effective treatment modality to reduce congestion, interstitial edema and increase neoangiogenesis in venous congested skin flaps. Our results suggests that growth factors of PRP in addition to M-induced activation of sensory nerve fibers increases tissue survival and regeneration.
Studies have shown that the 26S proteasome is involved in cell cycle control, transcription, DNA repair, immune response and protein synthesis. In the present study, we investigated the antiproliferative effects of the proteasome inhibitor bortezomib and heat shock protein (Hsp)70 inhibitors on the B16F10 melanoma cell line. The IC50 value of bortezomib was found to be 2.46 nM, while that of the Hsp70 inhibitor quercetin was 45 µM in the B16F10 cells. This indicates that bortezomib is more effective than quercetin in inhibiting cell growth. In response to treatment with 10 nM bortezomib for 24 h, cells underwent rounding, shrinkage and detachment. Unexpectedly, such morphological changes were not observed in cells treated with 20 µM quercetin alone, nor in cells treated with bortezomib + quercetin, indicating that quercetin inhibited the cytotoxic effects of bortezomib. Quantitation of cell viability also indicated that quercetin interfered with the cytotoxic effects of bortezomib. However, the combination of quercetin with another proteasome inhibitor, MG132, caused significant cell death as compared to single-agent treatment. A DNA ladder assay also confirmed the inhibitory effect of quercetin on the apoptosis-inducing effect of bortezomib. However, quercetin did not prevent the induction of apoptosis by MG132; on the contrary, it potentiated the apoptosis-inducing effect of MG132. These results suggest that the combination of quercetin with clinically beneficial proteasome inhibitors (except bortezomib) may have increased efficacy in the treatment of cancer. We also tested the combination of two other Hsp70 inhibitors, KNK-437 and schisandrin-B, in combination with bortezomib. Neither of these combinations was more effective than single-agent treatment.
Breast cancer treatments continue to be investigated with supported by new treatment methods. Melatonin is a hormone that can be effective in the treatment of breast cancer due to its anti-oxidant effect. Melatonin had previously shown to inhibit proliferation of cancer cells. In this study, we aimed to determine the effect of melatonin on the proliferation of metastatic breast cancer cells in comparison to doxorubicin, a well-known chemotherapeutic agent. Doxorubicin inhibited proliferation of metastatic breast cancer cells while melatonin has no effect. We are currently examining the effects of melatonin and doxorubicin combination therapy on metastatic breast cancer cells.
