"This person has the most self-determination of anyone I know.
"If she can overcome what she is going through and prove people wrong, I can do the same and run 100km solo."
Mariana is no slouch in sports shoes but training has been challenging, she says.
She aims to complete the distance in 22 hours - starting at 2am and finishing at midnight - the cut-off time for all relay participants who will rely on team members to share the burden.
She has remained active in sport playing touch and netball for Whakarewarewa Rugby Club, and participates in kapa haka with Nga Uri o te Whanoa.
"I have been keeping fit training for the 50th Rotorua Marathon in May but running alone for 22 hours is going to test my mental, physical and emotional reserves," she says.
"It will be quite a journey and I expect there will be times along the way that I will be saying 'why am I doing this'.
"I just need to think of my whanau to give me the motivation to keep going.
"I don't see myself as an ultra-distance runner - I'm just a local runner from Ohinemutu."
She has drawn inspiration from Kim Allen, an Auckland mother who ran 500km non-stop last year to support the New Zealand Spinal Trust.
"When I saw her finish I thought I can finish 100km," Mariana says.
Mariana will have plenty of encouragement from the sidelines from her grandmother Lady Kuia Morrison, wife of the late Sir Howard Morrison.
Lady Kuia, 76, has competed in a number of distance running events including marathons in New York, Sydney and her hometown Rotorua.
She will be offering vocal support to her granddaughter in the Relay for Life.
"I've always encouraged people to get out and do some exercise, even if it is a walk around the block," Lady Kuia says.
Cancer is the single biggest cause of death in New Zealand and most people will have some experience of it - either personally or through a relative, or friend, according to the Ministry of Health website.
Cancer of the lung, bowel or breast is the most common.
Many cancers can be cured if they're found and treated in time, and about one person in every three who gets cancer is cured, the website says.
The Cancer Society Relay for Life will be held at the International Stadium on March 15-16. Cost is $200 for teams of 10, extra team members $20. Contact Alia Ryan at rotorua@cancersociety.org.nz.
CANCER FACTS
In 2010, 21,235 cancers were registered in New Zealand - 52.1 per cent of the registrations were male.
Cancer was the leading cause of death for both males and females in New Zealand in 2010.
In 2010, 8593 people had cancer recorded as their underlying cause of death; of these deaths 52.5 per cent were male.
Between 2000 and 2010 the number of deaths from cancer increased by 12.8 per cent.
