Perforating collagenosis.

We show a case of a 69-year-old man with perforating collagenosis, which is a rare dermatosis commonly associated with diabetes mellitus. Papules and plaques with keratotic plugs are distinctive clinical characteristic of perforating collagenosis. Representative clinical images in our article can enhance the understanding of key concepts of perforating collagenous.

Soluble PD-L1 predicts tumor response and immune-related adverse events in patients with advanced melanoma treated with anti-PD-1 antibodies.

Immune checkpoint inhibitors (ICIs) bring prognostic benefits to patients with malignancies. However, there is a substantial number of patients whose lesions are not improved by ICIs. In addition, ICIs may cause immune-related adverse events (irAEs), which could lead to an unfavorable prognosis with fatal consequences. Therefore, we conducted a retrospective study to evaluate the utility of circulating sPD-L1 (soluble programmed cell death 1 ligand 1) as a biomarker in patients with advanced melanoma treated with anti-PD-1 (programmed cell death 1 protein) antibodies. Sera from 31 consecutive patients were prospectively collected before and after anti-PD-1 antibody treatment and the serum level of sPD-L1 was evaluated. We found that high sPD-L1 levels before treatment were associated with better prognosis, and this association was observed only in patients with a low tumor burden. We also found that sPD-L1 levels were elevated in patients who developed severe irAEs after treatment, and the patients with severe irAEs had significantly higher fluctuations in sPD-L1 (delta sPD-L1) than those without severe irAEs. Our study suggests that serum sPD-L1 level is a useful biomarker to predict tumor response and irAE development in patients with advanced melanoma treated with anti-PD-1 antibodies.

Pityriasis Rosea With Multiple Herald Patches Resulting in a V-shaped Pattern and a Christmas Tree Distribution.

Pityriasis rosea (PR), a benign and self-limiting skin disorder, typically manifests as a single initial lesion known as the herald patch. The herald patch is commonly followed by the development of secondary erythematous papules and plaques, aligning with Langer's lines to form a specific distribution pattern, resembling a Christmas tree on the back and a V-shaped pattern on the upper chest. Therefore, diagnosing PR may not be difficult based on its typical clinical presentation. In contrast, cases of atypical PR presentation have been reported, encompassing several differential diagnoses. Here, we present a case with multiple herald patches that needed differentiation from ringworm, syphilis, and erythema annular centrifugum. Subsequently, our case was diagnosed with PR, as the patches formed a V-shaped pattern and a Christmas-tree distribution.

Eribulin mesylate exerts antitumor effects via CD103.

Eribulin mesylate (ERB) is a synthetic analog of halichondrin B, inhibiting tumor cell growth by disrupting microtubule function. Recently, anticancer drugs have been shown to not only act directly on tumor cells but also to exert antitumor effects by modifying the tumor environment. Although ERB has also been speculated to modify the tumor microenvironment including the immune response to tumors, the precise mechanism remains unclear. In our study, ERB suppressed the tumor growth of MC38 colon cancer in wildtype mice, whereas ERB failed to inhibit the tumor growth in Rag1-deficient mice which lack both B and T cells. Moreover, depletion of either CD4+ or CD8+ T cells abrogated the antitumor effect of ERB, indicating that both CD4+ and CD8+ T cells play an important role in ERB-induced antitumor effects. Furthermore, ERB treatment increased the number of tumor infiltrating lymphocytes (TILs) as well as the expression of activation markers (CD38 and CD69), immune checkpoint molecules (LAG3, TIGIT and Tim3) and cytotoxic molecules (granzyme B and perforin) in TILs. ERB upregulated E-cadherin expression in MC38. CD103 is a ligand of E-cadherin and induces T-cell activation. ERB increased the proportion of CD103+ cells in both CD4+ and CD8+ TILs. The ERB-induced antitumor effect with the increased TIL number and the increased expression of activation markers, inhibitory checkpoint molecules and cytotoxic molecules in TILs was abrogated in CD103-deficient mice. Collectively, these results suggest that ERB exerts antitumor effects by upregulation of E-cadherin expression in tumor cells and subsequent activation of CD103+ TILs.

Artificial control of mating type and repeated mating to produce polyploid cells in Saccharomyces cerevisiae.

The budding yeast Saccharomyces cerevisiae is an excellent model for examining the effects of ploidy. Here, we provide a protocol for producing polyploid cells by creating a basic unit (matΔ) and polyploidizing it via repeated mating. We describe steps for basic unit construction by one-step transformation, increased ploidy via repeated mating, and ploidy confirmation using flow cytometry. This protocol can be broadly applied to evaluate the physiology of polyploid cells. For complete details on the use and execution of this protocol, please refer to Oya and Matsuura (2022).1.