In an emotional interview in July, Dele opened up on his mental health struggles, revealing he was sexually abused as a child and had spent six weeks in rehab to treat an addiction to sleeping pills as a result of childhood trauma.
Dele won back-to-back PFA Young Player of the Year awards while playing with Kane at Tottenham but his career went into sharp decline from around 2019, and he is now back at current club Everton after an unsuccessful loan spell in Turkey last season.
During the interview with Gary Neville, Dele singled out Kane and Eric Dier as "real friends" who were "brutally honest" in trying to help him through his challenges.
The pair played together for seven years at Spurs and were also England teammates but Kane said he had no idea about the extent of Dele's difficulties.
"I think it was extremely brave of Dele to come out and give the interview the gave, we have known each other for a period of time but I didn't know the extent of what he had been through in his life for sure," Kane said in Wroclaw, Poland, where he is preparing for England's European Championship qualifier against Ukraine on Saturday. "It was eye-opening for me to hear that.
"I text him after and said how much I think what he did will help a lot of other people share their feelings as well.
"I caught up with Dele in the summer, before the interview, and he seems to be on a good track, been working hard to get fit and so I can't wait to hopefully see him back out and playing football again.
"I think he is in a better place now and he has a lot of time left in his career and I really hope he can get back on track and play week in and week out."