Immunohistochemical Quantification of ARMC12 and RBBP4

Immunohistochemical staining was undertaken as described previously^{52 (link),53 (link),57 (link),62 (link)}, with antibodies specific for ARMC12 (ab72704, Abcam, 1:200 dilution) or RBBP4 (ab1765, Abcam, 1:200 dilution). To assess the reactivity degree, ten different high power fields (×400) for each specimen were blindly evaluated. The staining intensity was evaluated on a range from 0 to 3 (0, negative; 1, weakly positive; 2, moderately positive; 3, strongly positive), while percentage of positive cells were evaluated ranging from 0 to 4 (0, negative; 1, positive in 1−25%; 2, positive in 26−50%; 3, positive in 51−75%; 4, positive in 76−100%). Based on the products of staining intensity multiplied by percentage of positive cells, the results of immunohistochemistry were classified into negative (−, 0–1), mildly (+, 2–3), moderately (++, 4–8), and strongly positive (+++, 9–12). The moderate (++) or strong (+++) reactivity was defined as high expression, while negative (−) or mild positive (+) reactivity was defined as low expression.