Primary anorectal malignant melanoma treated with neoadjuvant chemoradiotherapy and sphincter-sparing surgery: A case report

α-Mangostin inhibits DMBA/TPA-induced skin cancer through inhibiting inflammation and promoting autophagy and apoptosis by regulating PI3K/Akt/mTOR signaling pathway in mice

Skin cancer is the most common form of cancer responsible for considerable morbidity and mortality, the treatment progress of which remains slow though. Therefore, studies identifying anti-skin cancer agents that are innocuous are urgently needed. α-Mangostin, a natural product isolated from the pericarp of mangosteen fruit, has potent anti-cancer activity. However, its role in skin cancer remains unclear. The aim of this study was to evaluate the treatment effect of α-mangostin on skin tumorigenesis induced by 9,10-dimethylbenz[a]anthracene (DMBA)/TPA in mice and the potential mechanism. Treatment with α-mangostin significantly suppressed tumor formation and growth, and markedly reduced the incidence rate. α-Mangostin not only inhibited the expressions of pro-inflammatory factors, but also promoted the production of anti-inflammatory factors in tumor and blood. It induced autophagy of skin tumor and regulated the expressions of autophagy-related proteins. The protein expressions of LC3, LC3-II and Beclin1 increased whereas those of LC3-I and p62 decreased after treatment with α-mangostin. Moreover, α-mangostin promoted the apoptosis of skin tumor dose-dependently by up-regulating of Bax, cleaved caspase-3, cleaved PARP and Bad, and down-regulating of Bcl-2 and Bcl-xl. Furthermore, showed α-mangostin inhibited the PI3K/AKT/mTOR (mammalian target of rapamycin) signaling pathway, as evidenced by decreased expressions of phospho-PI3K (p-PI3K), p-Akt and p-mTOR, but did not affect the expressions of t-PI3K, t-Akt or t-mTOR. Collectively, α-mangostin suppressed murine skin tumorigenesis induced by DMBA/TPA through inhibiting inflammation and promoting autophagy and apoptosis by regulating the PI3K/Akt/mTOR signaling pathway, as a potential candidate for future clinical therapy.

The first attempt in local excision of anorectal malignant melanoma using transanal endoscopic microsurgery

Anorectal malignant melanoma (AMM) is an uncommon malignancy that is thought to arise from melanocytes in the mucosa around the anorectal junction. AMM is commonly misdiagnosed, and definitive preoperative diagnosis is often difficult. The prognosis of AMM is relatively poor. Although radical resection is required for AMM, there is still no consensus at this moment on which surgical approach is preferred. We herein report a rare case of AMM which was treated by transanal endoscopic microsurgery (TEM) in combination with radiotherapy, which resulted in complete excision of the lesion without complications. The successful treatment for this AMM using TEM emphasizes the need to broaden its application in the treatment of various rectal lesions while preserving organ function and decreasing recurrence.