Narrow Histopathological Margins are Acceptable in Surgical Resection of Basal Cell Carcinoma in Japanese: A Single-Center Retrospective Study.

BACKGROUND: Basal cell carcinoma (BCC) is the most common cutaneous malignancy. BCCs occur mainly in exposed areas, such as the face and scalp. Therefore, surgical resection with narrow margins is highly desirable. However, narrow margins may increase the risk of positive histopathological margins. Outcomes for such treatment might be unfavorable, but evidence for such a conclusion is lacking. METHODS: Between April 2015 and November 2023, a total of 230 Japanese cases with BCC which underwent surgical resection with 2-mm, 3-mm, or 5-mm margins were followed in our hospital. We conducted a retrospective review that focused on the recurrence rate and histopathological margins. RESULTS: Recurrence was recorded if the follow-up time was longer than 3 months. One of the 198 cases (0.5%) developed a recurrence. The mean lateral and deep histopathological margins were 2,525.4 µm (30.8-14,034.6 µm) and 3,409 µm (199.9-16,523.6 µm), respectively. Recurrence rate was associated with tumor size and clinical tumor border. However, histopathological margin was not associated with recurrence rate, even when it was less than 1,000 µm. CONCLUSIONS: A narrow histopathological margin is acceptable for surgical resection of BCC in Japanese patients.

Cofilin plays a critical role in IL-8-dependent chemotaxis of neutrophilic HL-60 cells through changes in phosphorylation.

Cofilin is a ubiquitous, actin-binding protein. Only unphosphorylated cofilin binds actin and severs or depolymerizes filamentous actin (F-actin), and the inactive form of cofilin is phosphorylated at Ser 3. We reported recently that cofilin plays a regulatory role in superoxide production and phagocytosis by leukocytes, and in the present study, we investigated the role of cofilin in the chemotaxis of neutrophilic HL-60 cells. IL-8 is a potent, physiological chemokine, and it triggers a rapid, transient increase in F-actin beneath the plasma membrane and rapid dephosphorylation and subsequent rephosphorylation of cofilin. In this study, cofilin phosphorylation was found to be inhibited by S3-R peptide, which consists of a peptide corresponding to part of the phosphorylation site of cofilin and a membrane-permeable arginine polymer. When S3-R peptide was introduced into the neutrophilic cells, their chemotactic activity was enhanced, whereas a control peptide that contained an inverted sequence of the phosphorylation site of cofilin had no enhancing effect. Cofilin small interfering RNA (siRNA) decreased cofilin expression by about half and inhibited chemotaxis. In IL-8-stimulated cells, unphosphorylated cofilin accumulated around F-actin, and colocalization of F-actin and phosphorylated cofilin was observed, but these changes in cofilin localization were less prominent in cofilin siRNA-treated cells. The inhibitors of PI-3K wortmannin and LY294002 inhibited the chemotaxis and suppressed IL-8-evoked dephosphorylation and rephosphorylation of cofilin. These results suggested that unphosphorylated cofilin plays a critical role in leukocyte chemotaxis and that PI-3K is involved in the control of the phosphorylation/dephosphorylation cycle of cofilin.

Indirubin, a Chinese anti-leukaemia drug, promotes neutrophilic differentiation of human myelocytic leukaemia HL-60 cells.

Indirubin, a purple vegetable dye, is a traditional Chinese medicine for myelocytic leukaemia. Indirubin inhibits cyclin-dependent protein kinases (CDKs) and is present in human urine and serum. When indirubin was present during the neutrophilic differentiation of human myelocytic leukaemia HL-60 cells, it augmented superoxide production triggered by opsonized zymosan (OZ) by the terminally differentiated HL-60 cells. It also augmented the calcium response to OZ stimulation, and HL-60 cell chemotaxis evoked by interleukin-8 (IL-8, CXCL8) and formylpeptide. In addition, indirubin induced marked IL-8 release by the cells during differentiation and the cells differentiated with indirubin had typical neutrophilic properties, deformed nuclei and granules. Use of stable cloned HL-60 cells that contained a reporter vector for monitoring the activity of the transcription factor PU.1, which acts specifically at the stage of promyelocyte differentiation into neutrophils and monocytes, revealed that indirubin has a potent promoting activity on intracellular PU.1. Indirubin enhanced the expression of typical neutrophil proteins, including granulocyte-colony stimulating factor receptor, the beta2-integrin subunit CD18, the NADPH-oxidase subunit p47phox, and the IL-8 receptor CXCR1, all are controlled by PU.1. Indirubin also inhibited CDK2-dependent phosphorylation of retinoblastoma protein during neutrophilic differentiation. These results suggest that indirubin augments the neutrophilic differentiation of human myelocytic leukaemia HL-60 cells through inhibition of CDK2 and activation of PU.1.