One bottle of wine per week is associated with an increased absolute lifetime cancer risk for non-smokers of 1.0% (men) and 1.4% (women). The overall absolute increase in cancer risk for one bottle of wine per week equals that of five (men) or ten cigarettes per week (women).

I.e., not very much and could well be explained by other factors, including other lifestyle patterns, data inaccuracies (much of the data was from the UK Government's Health Survey for England which involves an interview of about 8000 people), etc.