**3. The role of lifestyle choices in cancer**

Billions of dollars are spent each year to research new therapeutic strategies against cancer. Still, millions of people die from the disease each year. Thus, successful prevention appears to be the better option and requires attacking the root causes of the disease. The best way to control cancer is to prevent it from happening in the first place. Geographic and economic differences in cancer incidence and mortality are striking. The types of cancer vary greatly between the developed and developing countries. Lung, prostate, breast and colorectal cancer are common in the developed countries like the US while ovarian, cervical, hepatocellular, and head and neck cancer are wide-spread in the poorer nations (Ott et al. 2011). **Table 1** lists the common cancers and their associated risk factors which can be avoided to prevent these malignancies.

with E6-associated protein (E6-AP) which is involved in the ubiquitin ligase pathway. E6- AP binds ubiquitin to p53, thereby flagging it for proteosomal degradation (Werness et al. 1990). In contrast, E7 competes for RB binding, freeing the transcription factor E2F to transactivate its targets, thus pushing the cell cycle forward (Dyson et al. 1989). Most HPV infections are cleared rapidly by the immune system and do not progress to cancer. Since the process of transforming normal cells into cancerous ones is slow, cancer occurs in people

Alcohol, a carcinogen, also causes a plethora of cancers (Wang et al. 2011, Chang, Straif and Guha 2011, Land et al. 2011, Pelucchi et al. 2008, Thomas 1995). Increased alcohol consumption has been linked to breast, liver, stomach, colorectal, melanoma, lung, and other cancers. Alcohol is thought to stimulate tumor growth by fuelling the production of growth factors that stimulate angiogenesis (Pelucchi et al. 2011). In addition, alcohol

Cigarette smoking leads to lung cancer since smoking exposes the individual to multiple DNA-damaging carcinogens and mutagens that result in mutations in critical genes that control cellular growth (Gonzalez et al. 2011, Hymowitz 2011, Lam and Minna 2011, Pesch et al. 2011, Proctor et al. 2011, Shields 2011). Moreover, smokers are exposed to multiple tumor promoting substances and inflammatory agents that exacerbate the process. Effective tobacco control led by clean air legislation, taxation, and anti-tobacco advertising is gradually contributing to decreased lung cancer incidence ((CDC) 2011, Bajoga et al. 2011, Ballbe et al. 2011, Kasza et al. 2011, King et al. 2011a, King et al. 2011b, Mage et al. 2011, Walsh et al. 2011). Thorough understanding of the biochemical, genetic and behavioral mechanisms of smoking can help us identify people who have a particularly high susceptibility to tobacco promoted cancers. These individuals can then be targeted for novel prevention measures, such as a nicotine vaccination and chemoprevention. Other simple individual steps that can help against developing cancer include vaccination (discussed in detail in a subsequent section) and screening for cervical cancer and hepatitis B, avoidance of excessive sun exposure for skin cancer, and limiting alcohol consumption for head and neck cancer and liver cancer (Pelucchi et al. 2008, Thomas 1995, Herrero et al. 2011, Chang et al. 2011, Pelucchi et al. 2011, No et al. 2011). Education and public outreach are immensely critical in this field. To this end, as research resources are allocated on cancer prevention, simultaneously there is a need to support scientific research to better understand the specific causes and mechanisms of cancers. Effort to identify susceptible individuals and target them

A number of studies have examined the impact of diet on cancer risk. Both the quantity and quality of food plays a role in cancer, with the former thought to be more critical. Some foods do contain anticancer compounds. Phytonutrients, often found in pungent and bitter vegetables, include resveratrol in grapes and curcumin in turmeric (Azari et al. 2009, Feeney 2004, Greenlee, Hershman and Jacobson 2009, Holst and Williamson 2008, Kale, Gawande and

suppresses immune activity. Thus, alcohol should only be consumed in moderation.

with persistent HPV infection.

for preventive interventions is necessary.

**3.2 Alcohol** 

**3.3 Smoking** 

**3.4 Diet** 


Table 1. Preventable cancers and their risk factors.
