如何在PrePlot()中将多个元素设置为斜体

类似的问题已经被多次提出(here、here和here).然而，在我的情况下，它并不起作用.

所以我有这段代码(见下文)，我想让"Column"Gene中的所有元素都变成斜体，除了标题(Gene)和摘要(Cancer).

使用expression(italic())会引发could not find function "italic"错误.我想，我不得不在这里使用fp_txt_italic()或txt_gp，但我就是不明白它们是如何工作的.也许有人能给我一些启发:).

我的代码(简化了，因为原始代码稍微复杂一些):

library(forestplot)
library(dplyr)


mean <- c(0.9, 1.0, 1.1, 1.0 )
lower <- c(0.8, 0.9, 1.0, 0.9 )
upper <- c(1.0, 1.1, 1.2, 1.1 )
gene <- c("TP53", "KRAS", "CBP", "Cancer")
p_value <- c(0.06, 0.05, 0.01, 0.05 )
n_pos <- c(30, 40, 35, 50)
n_neg  <- c(470, 460, 465, 450)


base_data <- tibble(mean = mean,
                    lower = lower,
                    upper = upper,
                    gene = gene,
                    n_pos = n_pos,
                    n_neg = n_neg,
                    p_value = p_value)


base_data |>
  filter(gene != "Cancer") |>
  forestplot(labeltext = c(gene, n_pos, n_neg, p_value),
             xlog = TRUE,
             vertices = TRUE,
             txt_gp = fpTxtGp(
               label = list(
                 grid::gpar(fontface = "italic"),
                 grid::gpar()))) |>
  fp_append_row(mean  = filter(base_data, gene == "Cancer")$mean,
                lower = filter(base_data, gene == "Cancer")$lower,
                upper = filter(base_data, gene == "Cancer")$upper,
                gene = filter(base_data, gene == "Cancer")$gene,
                n_pos = filter(base_data, gene == "Cancer")$n_pos,
                n_neg = filter(base_data, gene == "Cancer")$n_neg,
                p_value = filter(base_data, gene == "Cancer")$p_value,
                is.summary = TRUE) |>
  fp_add_header(gene = c("Gene\n"),
                n_pos = c("n(mutated)\n"),
                n_neg = c("n(wildtype)\n"),
                p_value = c("p\n")) |>
  fp_set_zebra_style("#EFEFEF") |>
  fp_add_lines() |>
  fp_decorate_graph(graph.pos = 2)