In vitro study examining the effect of sub-lethal QS 755 nm lasers on the expression of p16INK4a on melanoma cell lines

The palliative role of lasers in the treatment of melanoma

Melanoma, accounting for a significant proportion of skin cancer-related deaths, has variable survival outcomes based on the stage at diagnosis and treatment efficacy. Traditional treatments, while effective, pose risks of scarring and systemic side effects. Laser therapy offers an emerging non-surgical alternative, with CO2 lasers particularly showing promise in palliative care.A comprehensive search was conducted using PubMed, focusing on laser therapy for melanoma treatment. The search included studies on both stand-alone and adjunct laser therapies, with inclusion criteria requiring peer-reviewed articles detailing treatment outcomes for primary, recurrent, or metastatic melanoma.The literature shows that laser therapy for melanoma falls into four major types when categorized by laser medium: solid-state, diode, pulse-dye, and gas (CO2). Data on solid-state lasers for melanoma are limited and their use remains controversial. However, one study with high-energy pulsed neodymium lasers reported a 5-year survival of 82.9% with minimal adverse effects for primary melanoma. CO2 laser therapy has been effective for palliative treatment, with one study showing 54.8% of patients with recurrent melanoma surviving 5.4 years post-ablation. For metastatic melanoma, numerous studies have shown that CO2 laser therapy can provide symptomatic relief and disease control. Combination therapies using lasers and immune-based therapies have demonstrated enhanced outcomes and immune activation, highlighting the potential of laser therapies in melanoma management.While traditional treatments remain the standard for primary melanoma, laser therapies, particularly CO2 laser ablation, show substantial promise in palliative care for metastatic melanoma. Careful patient selection and assessment are crucial for achieving positive outcomes.

Lentigo maligna melanoma with a history of cosmetic treatment: Prevalence, surgical outcomes and considerations

INTRODUCTION

Lentigo maligna (LM) is melanoma in situ on sun-damaged skin and presents diagnostic challenges due to overlapping features with benign pigmented lesions. Cosmetic treatments may be inadvertently performed on LM. The aim of this study is to estimate the prevalence of LM with prior cosmetic treatment, and evaluate surgical outcomes.

STUDY DESIGN AND METHODS

Retrospective review of biopsy-proven LM presenting over a 10-year-period (2006-2015). Prior cosmetic treatment and biopsies were recorded. Records were reviewed for demographic data, clinical characteristics, and surgical outcomes.

RESULTS

37/503 (7.4%) patients with LM reported prior cosmetic therapy. Most (95%) were on the head and neck; mean size 1.9 cm. Most patients reported cryotherapy (73%), followed by laser (29.7%), topical bleaching agents (18.9%), and electrodessication, and/or curettage (5.3%). Ten patients (27%) received two or more modalities. Eight patients (21.6%) reported prior benign biopsies. Six patients (16%) had invasive disease, two on initial biopsy and 4/34 (11.7%) upstaged upon excision. Average margin for clearance was 9.1 mm.

CONCLUSION

Prior cosmetic treatment of LM is not uncommon, and may delay diagnosis and obscure borders, resulting in wider surgical margins. Clinicians should consider a biopsy confirming the benign nature of equivocal lesions prior to cosmetic treatment. Lasers Surg. Med. 49:819-826, 2017. © 2017 Wiley Periodicals, Inc.

The use of lasers in the treatment of skin cancer: A review

BACKGROUND

In considering skin cancer, a number of factors-including effectiveness, simplicity of treatment, cost, and esthetic outcomes-are important to ensure patient's satisfaction. There are several existing interventions, such as electrodessication and curettage, excision, Mohs surgery, radiation therapy, cryotherapy, and topical/oral treatments. Laser therapy has emerged as a new promising alternative that should be explored.

OBJECTIVE

To review the literature on the dermatological use of laser therapy in the treatment of skin cancer.

RESULTS

A review of articles available on the MEDLINE and Web of Science databases until May 2017 yielded 24 and 6 studies, respectively, on laser therapy in the treatment of skin cancers, particularly melanoma, basal cell carcinoma, and squamous cell carcinoma. The four laser subtypes included solid-state, diode, dye, and gas lasers.

CONCLUSION

Review of the literature demonstrates the progress of dermatological understanding of the clinical implications of laser therapy in the treatment of premalignant and malignant neoplasms of the skin, and suggests that this treatment modality might be a viable option for some patients.

Enhancement of monoclonal antibody production in CHO cells by exposure to He-Ne laser radiation

This study tested the effectiveness of laser biostimulation in small-scale cultures in vitro. We investigated the response of recombinant CHO cells, which are used for the production of monoclonal antibody, to low level laser radiation. The cells were irradiated using a 632.8 nm He-Ne laser in a continuous wave mode at different energy doses. We incubated the irradiated cells in small batch cultures and assessed their proliferation and productivity at various time intervals. Compared to untreated cells, the irradiated cells showed a significant increase in antibody production. Moreover, the results showed that laser irradiation did not affect viability and slightly enhanced proliferation rate.

Optimal management of common acquired melanocytic nevi (moles): current perspectives

Although common acquired melanocytic nevi are largely benign, they are probably one of the most common indications for cosmetic surgery encountered by dermatologists. With recent advances, noninvasive tools can largely determine the potential for malignancy, although they cannot supplant histology. Although surgical shave excision with its myriad modifications has been in vogue for decades, the lack of an adequate histological sample, the largely blind nature of the procedure, and the possibility of recurrence are persisting issues. Pigment-specific lasers were initially used in the Q-switched mode, which was based on the thermal relaxation time of the melanocyte (size 7 μm; 1 μsec), which is not the primary target in melanocytic nevus. The cluster of nevus cells (100 μm) probably lends itself to treatment with a millisecond laser rather than a nanosecond laser. Thus, normal mode pigment-specific lasers and pulsed ablative lasers (CO2/erbium [Er]:yttrium aluminum garnet [YAG]) are more suited to treat acquired melanocytic nevi. The complexities of treating this disorder can be overcome by following a structured approach by using lasers that achieve the appropriate depth to treat the three subtypes of nevi: junctional, compound, and dermal. Thus, junctional nevi respond to Q-switched/normal mode pigment lasers, where for the compound and dermal nevi, pulsed ablative laser (CO2/Er:YAG) may be needed. If surgical excision is employed, a wide margin and proper depth must be ensured, which is skill dependent. A lifelong follow-up for recurrence and melanoma is warranted in predisposed individuals, although melanoma is decidedly uncommon in most acquired melanocytic nevi, even though histological markers may be seen on evaluation.

Lasers for treatment of melasma and post-inflammatory hyperpigmentation

Hyperpigmentary disorders, especially melasma and post-inflammatory hyperpigmentation (PIH), cause significant social and emotional stress to the patients. Although many treatment modalities have been developed for melasma and PIH, its management still remains a challenge due to its recurrent and refractory nature. With the advent of laser technology, the treatment options have increased especially for dermal or mixed melasma. To review the literature on the use of cutaneous lasers for melasma and PIH. We carried out a PubMed search using following terms “lasers, IPL, melasma, PIH”. We cited the use of various lasers to treat melasma and PIH, including Q-switched Nd:YAG, Q-switched alexandrite, pulsed dye laser, and various fractional lasers. We describe the efficacy and safety of these lasers for the treatment of hyperpigmentation. Choosing the appropriate laser and the correct settings is vital in the treatment of melasma. The use of latter should be restricted to cases unresponsive to topical therapy or chemical peels. Appropriate maintenance therapy should be selected to avoid relapse of melasma.

Lentigines, laser, and melanoma: a case series and discussion

Solar lentigines are considered one of the earliest signs of photoaging and are an extremely common cosmetic complaint. Successful removal of these lesions can be achieved with laser and non-laser light sources, and is one of the most frequently performed cosmetic procedures in laser centers. Distinguishing a benign lentigo from other pigmented lesions can sometimes be challenging, even for a trained dermatologist. We report a series of three patients who presented to our laser center within 2 months of one another for cosmetic removal of pigmented lesions that were found to be melanoma. One patient was referred by another dermatologist, one by a physician family member, and the other presented on his own. These cases highlight the need for careful evaluation of pigmented lesions prior to laser treatment, regardless of the source of the referral. In this article, we will review the diagnostic and treatment differences between lentigines and their malignant counterparts, and examine the role of laser in both.

Burn unit experience treating giant melanocytic nevi: 10-year review

Giant congenital melanocytic nevi (GCMN) are rare lesions that are present in 1 in every 20,000 new births. A 10-year review of all patients treated at a pediatric burn center was performed with the goal of identifying the characteristics of patients with GCMN and the outcomes of the treatment provided in a burn center. Thirty-six patients met the definition of GCMN; 64% were female and 36% were male. The most common ethnicity was white (47%), followed by Latino (19%). Most patients were between the ages of 1 and 10 years at the time of their first procedure (64%), and the mean age of patients at the time of their first procedure was 7 years. Eighty-nine percent had only one lesion. The most common location of lesions was the face (64%), followed by the scalp (17%) and back (17%). Seventy-four percent of the samples sent to pathology were congenital compound melanocytic nevi, and 20% were congenital intradermal melanocytic nevi. None of the lesions contained malignant changes at the time of the pathological examination. The various treatment modalities provided in the burn unit are reviewed. The authors conclude that the burn unit is an ideal setting for the treatment of GCMN.

Giant congenital melanocytic nevi

BACKGROUND

: Giant congenital melanocytic nevi are rare lesions with the potential to regress into malignant melanoma and/or neurocutaneous melanosis. Appropriate investigations include a screening magnetic resonance imaging scan, neurologic evaluation, and serial clinical observations looking for the development of these complications. Numerous excisional and nonexcisional options have been described for the management of giant congenital melanocytic nevi.

METHODS

: A MEDLINE search was performed to obtain all relevant citations.

CONCLUSIONS

: To successfully treat these complex lesions, the plastic surgeon must understand the disease process, the natural history and complications, and the options for treatment.

The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm) on melanoma in vitro and in vivo

BACKGROUND

It has been speculated that the biostimulatory effect of Low Level Laser Therapy could cause undesirable enhancement of tumor growth in neoplastic diseases. The aim of the present study is to analyze the behavior of melanoma cells (B16F10) in vitro and the in vivo development of melanoma in mice after laser irradiation.

METHODS

We performed a controlled in vitro study on B16F10 melanoma cells to investigate cell viability and cell cycle changes by the Tripan Blue, MTT and cell quest histogram tests at 24, 48 and 72 h post irradiation. The in vivo mouse model (male Balb C, n = 21) of melanoma was used to analyze tumor volume and histological characteristics. Laser irradiation was performed three times (once a day for three consecutive days) with a 660 nm 50 mW CW laser, beam spot size 2 mm(2), irradiance 2.5 W/cm(2) and irradiation times of 60s (dose 150 J/cm(2)) and 420s (dose 1050 J/cm(2)) respectively.

RESULTS

There were no statistically significant differences between the in vitro groups, except for an increase in the hypodiploid melanoma cells (8.48 +/- 1.40% and 4.26 +/- 0.60%) at 72 h post-irradiation. This cancer-protective effect was not reproduced in the in vivo experiment where outcome measures for the 150 J/cm(2) dose group were not significantly different from controls. For the 1050 J/cm(2) dose group, there were significant increases in tumor volume, blood vessels and cell abnormalities compared to the other groups.

CONCLUSION

LLLT Irradiation should be avoided over melanomas as the combination of high irradiance (2.5 W/cm(2)) and high dose (1050 J/cm(2)) significantly increases melanoma tumor growth in vivo.

Giant congenital melanocytic nevi

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Define what is meant by a giant congenital melanocytic nevus and understand its histologic properties. 2. Know the natural history and potential complications associated with a giant congenital melanocytic nevus. 3. Outline the nonsurgical and surgical options available to treat a giant congenital melanocytic nevus.

BACKGROUND

Giant congenital melanocytic nevi are rare lesions with a propensity to degenerate to malignant melanoma. Certain lesions also may be associated with neurocutaneous melanosis, which can on occasion be symptomatic. Appropriate investigations include a screening magnetic resonance imaging scan, neurologic evaluation, and serial clinical observations for the development of cutaneous melanoma. A variety of nonsurgical and surgical options are possible for the treatment of giant congenital melanocytic nevi.

METHODS

A MEDLINE search was performed to gather all pertinent articles from 1955 to 2005.

RESULTS

Giant congenital melanocytic nevi are a difficult diagnostic and reconstructive challenge, requiring careful preoperative evaluation, staged surgical excision, and lifelong patient monitoring and follow-up. With proper treatment, patients can expect a decreased risk of melanoma, with the possibility for early detection and cure of melanoma, amelioration of symptoms, improved aesthetics and psychosocial sequelae, and maintenance of function.

CONCLUSION

The plastic surgeon treating these challenging lesions must have a solid working knowledge of the disease's histology, its natural history and complications, and the options for treatment.

An animal study of the effects on p16 and PCNA expression of repeated treatment with high-energy laser and intense pulsed light exposure

BACKGROUND AND OBJECTIVE

Non-ablative skin rejuvenation treatments that involve the use of laser/light sources together with cooling devices have gained much popularity in recent years due to the lack of down time that is associated with them. One important but neglected issue is long-term safety. Does the repeated use of non-ablative skin rejuvenation lead to photoaging? Are we creating another sun-bed phenomenon? Recently, we performed an in vitro study to examine the effect of sub-lethal QS 755 nm lasers on the expression of p16INK4a on melanoma cell lines, and found that sub-lethal laser damage could increase DNA damage, which led to an increase in p16 expression. Our objective was to assess the cutaneous effect of repeated exposure to high-energy lasers and intense pulsed light sources on male Institute of Cancer Research (ICR) mice.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-eight male ICR mice were divided into four groups. Other than the control group, all groups received either laser (585 nm pulsed dye laser or 1,320 nm Nd:YAG laser) or intense pulsed light (IPL) treatment. All four groups were anesthetized with a mixture of Hypnorm/Dormicum before treatment. The animals were irradiated twice a week for 6 months. Signs of toxicity such as mortality and weight loss were checked once a week. Skin tumor formation was evidenced by lesions of greater than 1 mm in diameter that persisted for 2 weeks. At the end of the 6 months, the expression of proliferating cell nuclear antigen (PCNA) and p16 in the mouse skin was determined by immunohistochemical staining and immunoblotting using specific monoclonal antibodies for mouse PCNA and p16. The results were expressed as mean +/- standard error of the mean (SEM). Statistical difference was assessed by multiple ANOVA. A P-value of <0.05 was considered to be significant.

RESULTS

At the end of the 6 months, none of the animals had developed any signs of toxicity such as mortality or weight lost. There was no evidence of tumor formation. There were significant elevations of p16 and PCNA in all treated groups as compared to the control group (ANOVA P < 0.05). This particularly applied to the group that was treated with the 1,320 nm Nd:YAG laser.

CONCLUSION

The repeated use of high-energy laser and intense pulsed light source did not cause any toxicity in mice. The changes in p16 and PCNA imply that further studies are necessary to consider the implications of repeated exposure to longer wavelength radiation in human skin.

Giant nevi: a review

Congenital nevi are benign neoplasms that are present at birth and composed of nevomelanocytes. Approximately 1-3% of all newborns have congenital pigmented nevi, and the number of nevi increases with age, peaking by late adolescence to 20-40 nevi in an individual. Giant congenital nevi are often defined as nevi that are greater than 20 cm in diameter in an adult, or nevi that occupy 2% or more of the body surface area. Histologically, nevi are transformed melanocytes, which are normally highly dendritic cells interspersed among basal keratinocytes. The genetic basis of these lesions is not known. Findings of a culture of melanocytes from such a lesion from a showed chromosome rearrangements involving 1p,12q, and 19p. The giant nevi might be associated to several diseases: neurocutaneous melanosis, diffuse lipomatosis, structural brain malformations, hypertrophy of skull bones, limb atrophy, skeletal asymmetry involving both soft tissue hyper-and hypoplasia, von Recklinghausen's disease and vitiligo. The risk of malignant change in giant nevi is probably the most contentious issue in its management. The consensus is that lesions are pre-malignant, but the purported incidence of malignancy varies wildly from 0-42%. Surgical excision remains the mainstay of treatment for large congenital melanocytic nevi, and most giant nevi are managed by staged excision and resurfacing with skin grafts or tissue expanders and flaps.

Wavelength dependence of cellular responses in human melanocytes and melanoma cells following exposure to ultraviolet radiation

PURPOSE

To examine the wavelength dependence of cellular responses in human melanocytes and human melanoma cells exposed to ultraviolet radiation (UVR).

MATERIALS AND METHODS

Primary human melanocytes and G361 human melanoma cells were exposed to ultraviolet-C (UVC), ultraviolet-B (UVB), or ultraviolet-A (UVA) radiation. Dose-response relationships for clonal cell survival were assessed, and flow cytometry was used to monitor cell cycle distributions for up to one week post-irradiation. Chromosomal aberrations were scored in exposed and unexposed melanoma cells.

RESULTS

G361 melanoma cells were more sensitive than melanocytes to killing by UVB and UVC radiation. This difference in sensitivity between cell types was much less marked following UVA irradiation. The melanoma cells showed a sustained, dose-dependent G2/M block following exposure with all wavelengths; in addition, transit through S phase was slowed following UVA irradiation. There was no apparent block to G1 cells entering S phase at any wavelength. Melanocytes, on the other hand, showed a marked G1 arrest, particularly following UVA irradiation. Cytogenetic results showed a dose-dependent increase in chromatid-type aberrations, mostly gaps, breaks and exchanges, in exposed melanoma cells.

CONCLUSION

These results show that G361 malignant melanoma cells have lost the ability to regulate the cell cycle at the G1/S checkpoint and are more sensitive than melanocytes to cell killing by UVC and UVB but not UVA radiation. Similarly, exposure of these melanoma cells to UVC and UVB, and to a much lesser extent UVA, induced chromatid aberrations. UVA nevertheless induced strong cell cycle delays in both cell types, indicating that UVA exposure can significantly affect genome metabolism.

Metastasis of a malignant melanoma 2 years after carbon dioxide laser treatment of a pigmented lesion: case report and review of the literature

A 64-year-old woman with a clinically diagnosed 'lentigo simplex' on her right cheek was dermatologically treated several times with a CO2 laser. Three years later she showed a metastasis of a malignant melanoma in her right parotid gland. Considering this case, as well as other published cases reporting malignant melanomas occurring after laser treatment, we again underscore that naevomelanocytic lesions are not a routine indication for laser treatment.

Recurrent pigmented macules after q-switched alexandrite laser treatment of congenital melanocytic nevus

BACKGROUND

Q-switch-mode laser treatment of congenital nevi does not result in complete histological clearance, and many patients have partial repigmentation within several months. In addition, the number of recurrent pigmented macules (RPMs) may increase, a major drawback to good cosmetic results. While the mechanism of recurrence is not known.

OBJECTIVE

To help elucidate the mechanism of RPM development, we evaluated the expression of TNF-alpha and E-cadherin on RPM after treatment of congenital nevi with a Q-switched alexandrite laser (QSAL).

METHODS

Thirteen Korean subjects with congenital nevi received QSAL treatment at intervals ranging from 2 to 6 months (mean, 4.5 treatments). Two-millimeter punch biopsy specimens were obtained at their first visit and from RPMs 3-6 months after the last treatment. Expression of E-cadherin and TNF-alpha were determined histochemically in the original nevi and RPM. In addition, one RPM was examined by electron microscopy.

RESULTS

Reduced pigmentation in the treated areas was seen in all cases, but partial repigmentaion was seen as black spots within 6 months after the last QSAL treatment. Compared to the original nevi, the RPMs had increased numbers of melanocytes in the epidermis and reduced nevomelanocytic nests in the dermis. The expression of TNF-alpha and E-cadherin was downregulated in the RPMs compared to the original nevi. Electron microscopy confirmed the increase in melanocytes in the epidermis of RPMs.

CONCLUSION

Our findings suggest that the down-regulation of E-cadherin and TNF-alpha may induce the proliferation of melanocytes, resulting in the formation of RPMs.